title: JPEG

text: Beginning in 2011 and continuing as of early 2013, an entity known as Princeton Digital Image Corporation, based in Eastern Texas, began suing large numbers of companies for alleged infringement of . Princeton claims that the JPEG image compression standard infringes the '056 patent and has sued large numbers of websites, retailers, camera and device manufacturers and resellers. The patent was originally owned and assigned to General Electric. The patent expired in December 2007, but Princeton has sued large numbers of companies for "past infringement" of this patent. (Under U.S. patent laws, a patent owner can sue for "past infringement" up to six years before the filing of a lawsuit, so Princeton could theoretically have continued suing companies until December 2013.) As of March 2013, Princeton had suits pending in New York and Delaware against more than 55 companies. General Electric's involvement in the suit is unknown, although court records indicate that it assigned the patent to Princeton in 2009 and retains certain rights in the patent.


title: JPEG

text: The JPEG compression algorithm operates at its best on photographs and paintings of realistic scenes with smooth variations of tone and color. For web usage, where reducing the amount of data used for an image is important for responsive presentation, JPEG's compression benefits make JPEG popular. JPEG/Exif is also the most common format saved by digital cameras.


title: JPEG

text: However, JPEG is not well suited for line drawings and other textual or iconic graphics, where the sharp contrasts between adjacent pixels can cause noticeable artifacts. Such images are better saved in a lossless graphics format such as TIFF, GIF, PNG, or a raw image format. The JPEG standard includes a lossless coding mode, but that mode is not supported in most products.


title: JPEG

text: As the typical use of JPEG is a lossy compression method, which reduces the image fidelity, it is inappropriate for exact reproduction of imaging data (such as some scientific and medical imaging applications and certain technical image processing work).


title: JPEG

text: JPEG is also not well suited to files that will undergo multiple edits, as some image quality is lost each time the image is recompressed, particularly if the image is cropped or shifted, or if encoding parameters are changed – see digital generation loss for details. To prevent image information loss during sequential and repetitive editing, the first edit can be saved in a lossless format, subsequently edited in that format, then finally published as JPEG for distribution.


title: JPEG

text: JPEG uses a lossy form of compression based on the discrete cosine transform (DCT). This mathematical operation converts each frame/field of the video source from the spatial (2D) domain into the frequency domain (a.k.a. transform domain). A perceptual model based loosely on the human psychovisual system discards high-frequency information, i.e. sharp transitions in intensity, and color hue. In the transform domain, the process of reducing information is called quantization. In simpler terms, quantization is a method for optimally reducing a large number scale (with different occurrences of each number) into a smaller one, and the transform-domain is a convenient representation of the image because the high-frequency coefficients, which contribute less to the overall picture than other coefficients, are characteristically small-values with high compressibility. The quantized coefficients are then sequenced and losslessly packed into the output bitstream. Nearly all software implementations of JPEG permit user control over the compression ratio (as well as other optional parameters), allowing the user to trade off picture-quality for smaller file size. In embedded applications (such as miniDV, which uses a similar DCT-compression scheme), the parameters are pre-selected and fixed for the application.


title: JPEG

text: The compression method is usually lossy, meaning that some original image information is lost and cannot be restored, possibly affecting image quality. There is an optional lossless mode defined in the JPEG standard. However, this mode is not widely supported in products.


title: JPEG

text: There is also an interlaced "progressive" JPEG format, in which data is compressed in multiple passes of progressively higher detail. This is ideal for large images that will be displayed while downloading over a slow connection, allowing a reasonable preview after receiving only a portion of the data. However, support for progressive JPEGs is not universal. When progressive JPEGs are received by programs that do not support them (such as versions of Internet Explorer before Windows 7) the software displays the image only after it has been completely downloaded.


title: JPEG

text: There are also many medical imaging, traffic and camera applications that create and process 12-bit JPEG images both grayscale and color. 12-bit JPEG format is included in an Extended part of the JPEG specification. The libjpeg codec supports 12-bit JPEG and there even exists a high-performance version.


title: JPEG

text: Several alterations to a JPEG image can be performed losslessly (that is, without recompression and the associated quality loss) as long as the image size is a multiple of 1 MCU block (Minimum Coded Unit) (usually 16 pixels in both directions, for 4:2:0 chroma subsampling). Utilities that implement this include:


title: JPEG

text: Blocks can be rotated in 90-degree increments, flipped in the horizontal, vertical and diagonal axes and moved about in the image. Not all blocks from the original image need to be used in the modified one.


title: JPEG

text: The top and left edge of a JPEG image must lie on an 8 × 8 pixel block boundary, but the bottom and right edge need not do so. This limits the possible lossless crop operations, and also prevents flips and rotations of an image whose bottom or right edge does not lie on a block boundary for all channels (because the edge would end up on top or left, where – as aforementioned – a block boundary is obligatory).


title: JPEG

text: Rotations where the image is not a multiple of 8 or 16, which value depends upon the chroma subsampling, are not lossless. Rotating such an image causes the blocks to be recomputed which results in loss of quality.


title: JPEG

text: When using lossless cropping, if the bottom or right side of the crop region is not on a block boundary, then the rest of the data from the partially used blocks will still be present in the cropped file and can be recovered. It is also possible to transform between baseline and progressive formats without any loss of quality, since the only difference is the order in which the coefficients are placed in the file.


title: JPEG

text: Furthermore, several JPEG images can be losslessly joined, as long as they were saved with the same quality and the edges coincide with block boundaries.


title: JPEG

text: The file format known as "JPEG Interchange Format" (JIF) is specified in Annex B of the standard. However, this "pure" file format is rarely used, primarily because of the difficulty of programming encoders and decoders that fully implement all aspects of the standard and because of certain shortcomings of the standard:


title: JPEG

text: Several additional standards have evolved to address these issues. The first of these, released in 1992, was the JPEG File Interchange Format (or JFIF), followed in recent years by Exchangeable image file format (Exif) and ICC color profiles. Both of these formats use the actual JIF byte layout, consisting of different "markers", but in addition, employ one of the JIF standard's extension points, namely the "application markers": JFIF uses APP0, while Exif uses APP1. Within these segments of the file that were left for future use in the JIF standard and are not read by it, these standards add specific metadata.


title: JPEG

text: Thus, in some ways, JFIF is a cut-down version of the JIF standard in that it specifies certain constraints (such as not allowing all the different encoding modes), while in other ways, it is an extension of JIF due to the added metadata. The documentation for the original JFIF standard states:


title: JPEG

text: Image files that employ JPEG compression are commonly called "JPEG files", and are stored in variants of the JIF image format. Most image capture devices (such as digital cameras) that output JPEG are actually creating files in the Exif format, the format that the camera industry has standardized on for metadata interchange. On the other hand, since the Exif standard does not allow color profiles, most image editing software stores JPEG in JFIF format, and also includes the APP1 segment from the Exif file to include the metadata in an almost-compliant way; the JFIF standard is interpreted somewhat flexibly.


title: JPEG

text: Strictly speaking, the JFIF and Exif standards are incompatible, because each specifies that its marker segment (APP0 or APP1, respectively) appear first. In practice, most JPEG files contain a JFIF marker segment that precedes the Exif header. This allows older readers to correctly handle the older format JFIF segment, while newer readers also decode the following Exif segment, being less strict about requiring it to appear first.


title: JPEG

text: The most common filename extensions for files employing JPEG compression are codice_1 and codice_2, though codice_5, codice_6 and codice_7 are also used. It is also possible for JPEG data to be embedded in other file types – TIFF encoded files often embed a JPEG image as a thumbnail of the main image; and MP3 files can contain a JPEG of cover art in the ID3v2 tag.


title: JPEG

text: Many JPEG files embed an ICC color profile (color space). Commonly used color profiles include sRGB and Adobe RGB. Because these color spaces use a non-linear transformation, the dynamic range of an 8-bit JPEG file is about 11 stops; see gamma curve.


title: JPEG

text: If the image doesn't specify color profile information ("untagged"), the color space is assumed to be sRGB for the purposes of display on webpages.


title: JPEG

text: A JPEG image consists of a sequence of "segments", each beginning with a "marker", each of which begins with a 0xFF byte, followed by a byte indicating what kind of marker it is. Some markers consist of just those two bytes; others are followed by two bytes (high then low), indicating the length of marker-specific payload data that follows. (The length includes the two bytes for the length, but not the two bytes for the marker.) Some markers are followed by entropy-coded data; the length of such a marker does not include the entropy-coded data. Note that consecutive 0xFF bytes are used as fill bytes for padding purposes, although this fill byte padding should only ever take place for markers immediately following entropy-coded scan data (see JPEG specification section B.1.1.2 and E.1.2 for details; specifically "In all cases where markers are appended after the compressed data, optional 0xFF fill bytes may precede the marker").


title: JPEG

text: Within the entropy-coded data, after any 0xFF byte, a 0x00 byte is inserted by the encoder before the next byte, so that there does not appear to be a marker where none is intended, preventing framing errors. Decoders must skip this 0x00 byte. This technique, called byte stuffing (see JPEG specification section F.1.2.3), is only applied to the entropy-coded data, not to marker payload data. Note however that entropy-coded data has a few markers of its own; specifically the Reset markers (0xD0 through 0xD7), which are used to isolate independent chunks of entropy-coded data to allow parallel decoding, and encoders are free to insert these Reset markers at regular intervals (although not all encoders do this).


title: JPEG

text: Since several vendors might use the same APP"n" marker type, application-specific markers often begin with a standard or vendor name (e.g., "Exif" or "Adobe") or some other identifying string.


title: JPEG

text: At a restart marker, block-to-block predictor variables are reset, and the bitstream is synchronized to a byte boundary. Restart markers provide means for recovery after bitstream error, such as transmission over an unreliable network or file corruption. Since the runs of macroblocks between restart markers may be independently decoded, these runs may be decoded in parallel.


title: JPEG

text: Although a JPEG file can be encoded in various ways, most commonly it is done with JFIF encoding. The encoding process consists of several steps:


title: JPEG

text: The decoding process reverses these steps, except the "quantization" because it is irreversible. In the remainder of this section, the encoding and decoding processes are described in more detail.


title: JPEG

text: Many of the options in the JPEG standard are not commonly used, and as mentioned above, most image software uses the simpler JFIF format when creating a JPEG file, which among other things specifies the encoding method. Here is a brief description of one of the more common methods of encoding when applied to an input that has 24 bits per pixel (eight each of red, green, and blue). This particular option is a lossy data compression method.


title: JPEG

text: First, the image should be converted from RGB (by default sRGB, but other color spaces are possible) into a different color space called (or, informally, YCbCr). It has three components Y', C and C: the Y' component represents the brightness of a pixel, and the C and C components represent the chrominance (split into blue and red components). This is basically the same color space as used by digital color television as well as digital video including video DVDs. The color space conversion allows greater compression without a significant effect on perceptual image quality (or greater perceptual image quality for the same compression). The compression is more efficient because the brightness information, which is more important to the eventual perceptual quality of the image, is confined to a single channel. This more closely corresponds to the perception of color in the human visual system. The color transformation also improves compression by statistical decorrelation.


title: JPEG

text: A particular conversion to is specified in the JFIF standard, and should be performed for the resulting JPEG file to have maximum compatibility. However, some JPEG implementations in "highest quality" mode do not apply this step and instead keep the color information in the RGB color model, where the image is stored in separate channels for red, green and blue brightness components. This results in less efficient compression, and would not likely be used when file size is especially important.


title: JPEG

text: Due to the densities of color- and brightness-sensitive receptors in the human eye, humans can see considerably more fine detail in the brightness of an image (the Y' component) than in the hue and color saturation of an image (the Cb and Cr components). Using this knowledge, encoders can be designed to compress images more efficiently.


title: JPEG

text: The transformation into the color model enables the next usual step, which is to reduce the spatial resolution of the Cb and Cr components (called "downsampling" or "chroma subsampling"). The ratios at which the downsampling is ordinarily done for JPEG images are (no downsampling), (reduction by a factor of 2 in the horizontal direction), or (most commonly) (reduction by a factor of 2 in both the horizontal and vertical directions). For the rest of the compression process, Y', Cb and Cr are processed separately and in a very similar manner.


title: JPEG

text: After subsampling, each channel must be split into 8×8 blocks. Depending on chroma subsampling, this yields Minimum Coded Unit (MCU) blocks of size 8×8 (4:4:4 – no subsampling), 16×8 (4:2:2), or most commonly 16×16 (4:2:0). In video compression MCUs are called macroblocks.


title: JPEG

text: If the data for a channel does not represent an integer number of blocks then the encoder must fill the remaining area of the incomplete blocks with some form of dummy data. Filling the edges with a fixed color (for example, black) can create ringing artifacts along the visible part of the border;


title: JPEG

text: repeating the edge pixels is a common technique that reduces (but does not necessarily eliminate) such artifacts, and more sophisticated border filling techniques can also be applied.


title: JPEG

text: Next, each 8×8 block of each component (Y, Cb, Cr) is converted to a frequency-domain representation, using a normalized, two-dimensional type-II discrete cosine transform (DCT), see Citation 1 in discrete cosine transform. The DCT is sometimes referred to as "type-II DCT" in the context of a family of transforms as in discrete cosine transform, and the corresponding inverse (IDCT) is denoted as "type-III DCT".


title: JPEG

text: Before computing the DCT of the 8×8 block, its values are shifted from a positive range to one centered on zero. For an 8-bit image, each entry in the original block falls in the range formula_2. The midpoint of the range (in this case, the value 128) is subtracted from each entry to produce a data range that is centered on zero, so that the modified range is formula_3. This step reduces the dynamic range requirements in the DCT processing stage that follows.


title: JPEG

text: If we perform this transformation on our matrix above, we get the following (rounded to the nearest two digits beyond the decimal point):


title: JPEG

text: Note the top-left corner entry with the rather large magnitude. This is the DC coefficient (also called the constant component), which defines the basic hue for the entire block. The remaining 63 coefficients are the AC coefficients (also called the alternating components). The advantage of the DCT is its tendency to aggregate most of the signal in one corner of the result, as may be seen above. The quantization step to follow accentuates this effect while simultaneously reducing the overall size of the DCT coefficients, resulting in a signal that is easy to compress efficiently in the entropy stage.


title: JPEG

text: The DCT temporarily increases the bit-depth of the data, since the DCT coefficients of an 8-bit/component image take up to 11 or more bits (depending on fidelity of the DCT calculation) to store. This may force the codec to temporarily use 16-bit numbers to hold these coefficients, doubling the size of the image representation at this point; these values are typically reduced back to 8-bit values by the quantization step. The temporary increase in size at this stage is not a performance concern for most JPEG implementations, since typically only a very small part of the image is stored in full DCT form at any given time during the image encoding or decoding process.


title: JPEG

text: The human eye is good at seeing small differences in brightness over a relatively large area, but not so good at distinguishing the exact strength of a high frequency brightness variation. This allows one to greatly reduce the amount of information in the high frequency components. This is done by simply dividing each component in the frequency domain by a constant for that component, and then rounding to the nearest integer. This rounding operation is the only lossy operation in the whole process (other than chroma subsampling) if the DCT computation is performed with sufficiently high precision. As a result of this, it is typically the case that many of the higher frequency components are rounded to zero, and many of the rest become small positive or negative numbers, which take many fewer bits to represent.


title: JPEG

text: The elements in the quantization matrix control the compression ratio, with larger values producing greater compression. A typical quantization matrix (for a quality of 50% as specified in the original JPEG Standard), is as follows:


title: JPEG

text: where formula_18 is the unquantized DCT coefficients; formula_19 is the quantization matrix above; and formula_20 is the quantized DCT coefficients.


title: JPEG

text: Notice that most of the higher-frequency elements of the sub-block (i.e., those with an "x" or "y" spatial frequency greater than 4) are quantized into zero values.


title: JPEG

text: Entropy coding is a special form of lossless data compression. It involves arranging the image components in a "zigzag" order employing run-length encoding (RLE) algorithm that groups similar frequencies together, inserting length coding zeros, and then using Huffman coding on what is left.


title: JPEG

text: The JPEG standard also allows, but does not require, decoders to support the use of arithmetic coding, which is mathematically superior to Huffman coding. However, this feature has rarely been used, as it was historically covered by patents requiring royalty-bearing licenses, and because it is slower to encode and decode compared to Huffman coding. Arithmetic coding typically makes files about 5–7% smaller.


title: JPEG

text: The previous quantized DC coefficient is used to predict the current quantized DC coefficient. The difference between the two is encoded rather than the actual value. The encoding of the 63 quantized AC coefficients does not use such prediction differencing.


title: JPEG

text: The zigzag sequence for the above quantized coefficients are shown below. (The format shown is just for ease of understanding/viewing.)


title: JPEG

text: If the "i"-th block is represented by formula_23 and positions within each block are represented by formula_24 where formula_25 and formula_26, then any coefficient in the DCT image can be represented as formula_27. Thus, in the above scheme, the order of encoding pixels (for the -th block) is formula_28, formula_29, formula_30, formula_31, formula_32, formula_33, formula_34, formula_35 and so on.


title: JPEG

text: This encoding mode is called baseline "sequential" encoding. Baseline JPEG also supports "progressive" encoding. While sequential encoding encodes coefficients of a single block at a time (in a zigzag manner), progressive encoding encodes similar-positioned batch of coefficients of all blocks in one go (called a "scan"), followed by the next batch of coefficients of all blocks, and so on. For example, if the image is divided into N 8×8 blocks formula_36, then a 3-scan progressive encoding encodes DC component, formula_28 for all blocks, i.e., for all formula_38, in first scan. This is followed by the second scan which encoding a few more components (assuming four more components, they are formula_29 to formula_32, still in a zigzag manner) coefficients of all blocks (so the sequence is: formula_41), followed by all the remained coefficients of all blocks in the last scan.


title: JPEG

text: Once all similar-positioned coefficients have been encoded, the next position to be encoded is the one occurring next in the zigzag traversal as indicated in the figure above. It has been found that "baseline progressive" JPEG encoding usually gives better compression as compared to "baseline sequential" JPEG due to the ability to use different Huffman tables (see below) tailored for different frequencies on each "scan" or "pass" (which includes similar-positioned coefficients), though the difference is not too large.


title: JPEG

text: In the rest of the article, it is assumed that the coefficient pattern generated is due to sequential mode.


title: JPEG

text: In order to encode the above generated coefficient pattern, JPEG uses Huffman encoding. The JPEG standard provides general-purpose Huffman tables; encoders may also choose to generate Huffman tables optimized for the actual frequency distributions in images being encoded.


title: JPEG

text: The process of encoding the zig-zag quantized data begins with a run-length encoding explained below, where:


title: JPEG

text: The run-length encoding works by examining each non-zero AC coefficient and determining how many zeroes came before the previous AC coefficient. With this information, two symbols are created:


title: JPEG

text: Both "RUNLENGTH" and "SIZE" rest on the same byte, meaning that each only contains four bits of information. The higher bits deal with the number of zeroes, while the lower bits denote the number of bits necessary to encode the value of .


title: JPEG

text: This has the immediate implication of "Symbol 1" being only able store information regarding the first 15 zeroes preceding the non-zero AC coefficient. However, JPEG defines two special Huffman code words. One is for ending the sequence prematurely when the remaining coefficients are zero (called "End-of-Block" or "EOB"), and another when the run of zeroes goes beyond 15 before reaching a non-zero AC coefficient. In such a case where 16 zeroes are encountered before a given non-zero AC coefficient, "Symbol 1" is encoded "specially" as: (15, 0)(0).


title: JPEG

text: From here, frequency calculations are made based on occurrences of the coefficients. In our example block, most of the quantized coefficients are small numbers that are not preceded immediately by a zero coefficient. These more-frequent cases will be represented by shorter code words.


title: JPEG

text: The resulting compression ratio can be varied according to need by being more or less aggressive in the divisors used in the quantization phase. Ten to one compression usually results in an image that cannot be distinguished by eye from the original. A compression ratio of 100:1 is usually possible, but will look distinctly artifacted compared to the original. The appropriate level of compression depends on the use to which the image will be put.


title: JPEG

text: Those who use the World Wide Web may be familiar with the irregularities known as compression artifacts that appear in JPEG images, which may take the form of noise around contrasting edges (especially curves and corners), or "blocky" images. These are due to the quantization step of the JPEG algorithm. They are especially noticeable around sharp corners between contrasting colors (text is a good example, as it contains many such corners). The analogous artifacts in MPEG video are referred to as "mosquito noise," as the resulting "edge busyness" and spurious dots, which change over time, resemble mosquitoes swarming around the object.


title: JPEG

text: These artifacts can be reduced by choosing a lower level of compression; they may be completely avoided by saving an image using a lossless file format, though this will result in a larger file size. The images created with ray-tracing programs have noticeable blocky shapes on the terrain. Certain low-intensity compression artifacts might be acceptable when simply viewing the images, but can be emphasized if the image is subsequently processed, usually resulting in unacceptable quality. Consider the example below, demonstrating the effect of lossy compression on an edge detection processing step.


title: JPEG

text: Some programs allow the user to vary the amount by which individual blocks are compressed. Stronger compression is applied to areas of the image that show fewer artifacts. This way it is possible to manually reduce JPEG file size with less loss of quality.


title: JPEG

text: Since the quantization stage "always" results in a loss of information, JPEG standard is always a lossy compression codec. (Information is lost both in quantizing and rounding of the floating-point numbers.) Even if the quantization matrix is a matrix of ones, information will still be lost in the rounding step.


title: JPEG

text: Rounding the output to integer values (since the original had integer values) results in an image with values (still shifted down by 128)


title: JPEG

text: This is the decompressed subimage. In general, the decompression process may produce values outside the original input range of formula_2. If this occurs, the decoder needs to clip the output values so as to keep them within that range to prevent overflow when storing the decompressed image with the original bit depth.


title: JPEG

text: The decompressed subimage can be compared to the original subimage (also see images to the right) by taking the difference (original − uncompressed) results in the following error values:


title: JPEG

text: The error is most noticeable in the bottom-left corner where the bottom-left pixel becomes darker than the pixel to its immediate right.


title: JPEG

text: The required implementation precision of a JPEG codec is implicitly defined through the requirements formulated for compliance to the JPEG standard. These requirements are specified in ITU.T Recommendation T.83 | ISO/IEC 10918-2. Unlike MPEG standards and many later JPEG standards, the above document defines both required implementation precisions for the encoding and the decoding process of a JPEG codec by means of a maximal tolerable error of the forwards and inverse DCT in the DCT domain as determined by reference test streams. For example, the output of a decoder implementation must not exceed an error of one quantization unit in the DCT domain when applied to the reference testing codestreams provided as part of the above standard. While unusual, and unlike many other and more modern standards, ITU.T T.83 | ISO/IEC 10918-2 does not formulate error bounds in the image domain.


title: JPEG

text: JPEG compression artifacts blend well into photographs with detailed non-uniform textures, allowing higher compression ratios. Notice how a higher compression ratio first affects the high-frequency textures in the upper-left corner of the image, and how the contrasting lines become more fuzzy. The very high compression ratio severely affects the quality of the image, although the overall colors and image form are still recognizable. However, the precision of colors suffer less (for a human eye) than the precision of contours (based on luminance). This justifies the fact that images should be first transformed in a color model separating the luminance from the chromatic information, before subsampling the chromatic planes (which may also use lower quality quantization) in order to preserve the precision of the luminance plane with more information bits.


title: JPEG

text: For information, the uncompressed 24-bit RGB bitmap image below (73,242 pixels) would require 219,726 bytes (excluding all other information headers). The filesizes indicated below include the internal JPEG information headers and some metadata. For highest quality images (Q=100), about 8.25 bits per color pixel is required. On grayscale images, a minimum of 6.5 bits per pixel is enough (a comparable Q=100 quality color information requires about 25% more encoded bits). The highest quality image below (Q=100) is encoded at nine bits per color pixel, the medium quality image (Q=25) uses one bit per color pixel. For most applications, the quality factor should not go below 0.75 bit per pixel (Q=12.5), as demonstrated by the low quality image. The image at lowest quality uses only 0.13 bit per pixel, and displays very poor color. This is useful when the image will be displayed in a significantly scaled-down size. A method for creating better quantization matrices for a given image quality using PSNR instead of the Q factor is described in Minguillón & Pujol (2001).


title: JPEG

text: The medium quality photo uses only 4.3% of the storage space required for the uncompressed image, but has little noticeable loss of detail or visible artifacts. However, once a certain threshold of compression is passed, compressed images show increasingly visible defects. See the article on rate–distortion theory for a mathematical explanation of this threshold effect. A particular limitation of JPEG in this regard is its non-overlapped 8×8 block transform structure. More modern designs such as JPEG 2000 and JPEG XR exhibit a more graceful degradation of quality as the bit usage decreases – by using transforms with a larger spatial extent for the lower frequency coefficients and by using overlapping transform basis functions.


title: JPEG

text: From 2004 to 2008, new research emerged on ways to further compress the data contained in JPEG images without modifying the represented image. This has applications in scenarios where the original image is only available in JPEG format, and its size needs to be reduced for archiving or transmission. Standard general-purpose compression tools cannot significantly compress JPEG files.


title: JPEG

text: Typically, such schemes take advantage of improvements to the naive scheme for coding DCT coefficients, which fails to take into account:


title: JPEG

text: Some standard but rarely used options already exist in JPEG to improve the efficiency of coding DCT coefficients: the arithmetic coding option, and the progressive coding option (which produces lower bitrates because values for each coefficient are coded independently, and each coefficient has a significantly different distribution). Modern methods have improved on these techniques by reordering coefficients to group coefficients of larger magnitude together; using adjacent coefficients and blocks to predict new coefficient values; dividing blocks or coefficients up among a small number of independently coded models based on their statistics and adjacent values; and most recently, by decoding blocks, predicting subsequent blocks in the spatial domain, and then encoding these to generate predictions for DCT coefficients.


title: JPEG

text: Typically, such methods can compress existing JPEG files between 15 and 25 percent, and for JPEGs compressed at low-quality settings, can produce improvements of up to 65%.


title: JPEG

text: A freely available tool called packJPG is based on the 2007 paper "Improved Redundancy Reduction for JPEG Files."


title: JPEG

text: JPS is a stereoscopic JPEG image used for creating 3D effects from 2D images. It contains two static images, one for the left eye and one for the right eye; encoded as two side-by-side images in a single JPG file.


title: JPEG

text: JPEG Stereoscopic (JPS, extension .jps) is a JPEG-based format for stereoscopic images. It has a range of configurations stored in the JPEG APP3 marker field, but usually contains one image of double width, representing two images of identical size in cross-eyed (i.e. left frame on the right half of the image and vice versa) side-by-side arrangement. This file format can be viewed as a JPEG without any special software, or can be processed for rendering in other modes.


title: JPEG

text: JPEG Multi-Picture Format (MPO, extension .mpo) is a JPEG-based format for storing multiple images in a single file. It contains two or more JPEG files concatenated together. It also defines a JPEG APP2 marker segment for image description. Various devices use it to store 3D images, such as Fujifilm FinePix Real 3D W1, HTC Evo 3D, JVC GY-HMZ1U AVCHD/MVC extension camcorder, Nintendo 3DS, Panasonic Lumix DMC-TZ20, DMC-TZ30, DMC-TZ60, DMC-TS4 (FT4), and Sony DSC-HX7V. Other devices use it to store "preview images" that can be displayed on a TV.


title: JPEG

text: In the last few years, due to the growing use of stereoscopic images, much effort has been spent by the scientific community to develop algorithms for stereoscopic image compression.


title: JPEG

text: A very important implementation of a JPEG codec is the free programming library "libjpeg" of the Independent JPEG Group. It was first published in 1991 and was key for the success of the standard. This library or a direct derivative of it is used in countless applications. Recent versions introduced proprietary extensions, breaking ABI compatibility with previous versions and which are not covered by the ITU|ISO/IEC standard.


title: JPEG

text: In March 2017, Google released the open source project Guetzli, which trades off a much longer encoding time for smaller file size (similar to what Zopfli does for PNG and other lossless data formats).


title: JPEG

text: ITU|ISO/IEC formalized JPEG reference implementations in ITU-T Recommendation T.873 | ISO/IEC 10918-7 in 2021.


title: JPEG

text: ISO/IEC Joint Photography Experts Group maintains one of the two reference software implementations which can encode both base JPEG (ISO/IEC 10918-1 and 18477–1) and JPEG XT extensions (ISO/IEC 18477 Parts 2 and 6–9), as well as JPEG-LS (ISO/IEC 14495).


title: JPEG

text: A second reference implementation is libJPEG-turbo which is a derivate of the JPEG implementation of the Indedependent JPEG Group tuned towards high performance and compliance to the JPEG standard.


title: JPEG

text: JPEG XT (ISO/IEC 18477) was published in June 2015; it extends base JPEG format with support for higher integer bit depths (up to 16 bit), high dynamic range imaging and floating-point coding, lossless coding, and alpha channel coding. Extensions are backward compatible with the base JPEG/JFIF file format and 8-bit lossy compressed image. JPEG XT uses an extensible file format based on JFIF. Extension layers are used to modify the JPEG 8-bit base layer and restore the high-resolution image. Existing software is forward compatible and can read the JPEG XT binary stream, though it would only decode the base 8-bit layer.


title: JPEG

text: Since August 2017, JTC1/SC29/WG1 issued a series of draft calls for proposals on JPEG XLthe next generation image compression standard with substantially better compression efficiency (60% improvement) comparing to JPEG. The standard is expected to exceed the still image compression performance shown by HEVC HM, Daala and WebP, and unlike previous efforts attempting to replace JPEG, to provide lossless more efficient recompression transport and storage option for traditional JPEG images. The core requirements include support for very high-resolution images (at least 40 MP), 8–10 bits per component, RGB/YCbCr/ICtCp color encoding, animated images, alpha channel coding, Rec. 709 color space (sRGB) and gamma function (2.4-power), Rec. 2100 wide color gamut color space (Rec. 2020) and high dynamic range transfer functions (PQ and HLG), and high-quality compression of synthetic images, such as bitmap fonts and gradients. The standard should also offer higher bit depths (12–16 bit integer and floating point), additional color spaces and transfer functions (such as Log C from Arri), embedded preview images, lossless alpha channel encoding, image region coding, and low-complexity encoding. Any patented technologies would be licensed on a royalty-free basis. The proposals were submitted by September 2018, leading to a committee draft in July 2019, with file format and core coding system were formally standardized on 13 October 2021 and 30 March 2022 respectively.


title: Rajendra Prasad

text: Rajendra Prasad (3 December 1884 – 28 February 1963) was an Indian politician, lawyer, Indian independence activist, journalist & scholar who served as the first president of Republic of India from 1950 to 1962. He joined the Indian National Congress during the Indian Independence Movement and became a major leader from the region of Bihar and Maharashtra. A supporter of Mahatma Gandhi, Prasad was imprisoned by British authorities during the Salt Satyagraha of 1931 and the Quit India movement of 1942. After the constituent assembly 1946 elections, Prasad served as Minister of Food and Agriculture in the central government. Upon independence in 1947, Prasad was elected as President of the Constituent Assembly of India, which prepared the Constitution of India and served as its provisional Parliament.


title: Rajendra Prasad

text: When India became a republic in 1950, Prasad was elected its first president by the Constituent Assembly. As president, Prasad established a tradition for non - partisanship and independence for the office-bearer and retired from Congress party politics. Although a ceremonial head of state, Prasad encouraged the development of education in India and advised the Nehru government on several occasions. In 1957, Prasad was re-elected to the presidency, becoming the only president to serve two full terms. Prasad stayed in office for the longest term of around 12 years. Post the completion of his tenure, he quit the Congress and set up new guidelines for parliamentarians which are still followed.


title: Rajendra Prasad

text: Rajendra Prasad was born in a Kayastha family in Ziradei, in the Siwan district of Bihar during the British Raj. His father, Mahadev Sahai Srivastava, was a scholar of both Sanskrit and Persian languages. His mother, Kamleshwari Devi, was a devout woman who would tell stories from the Ramayana and Mahabharata to her son. He was the youngest child and had one elder brother and three elder sisters. His mother died when he was a child, and his elder sister then took care of him.


title: Rajendra Prasad

text: After the completion of traditional elementary education, he was sent to the Chapra District School. Meanwhile, in June 1896, at the early age of 12, he was married to Rajavanshi Devi. He, along with his elder brother, Mahendra Prasad, then went to study at T.K. Ghosh's Academy in Patna for a period of two years. He secured first in the entrance examination to the University of Calcutta and was awarded Rs. 30 per month as a scholarship.


title: Rajendra Prasad

text: Prasad joined the Presidency College, Calcutta in 1902, initially as a science student. He passed the F. A. under the University of Calcutta in March 1904 and then graduated with a first division from there in March 1905. Impressed by his intellect, an examiner once commented on his answer sheet that the ""examinee is better than examiner"". Later he decided to focus on the study of arts and did his M.A. in Economics with a first division from the University of Calcutta in December 1907. There he lived with his brother in the Eden Hindu Hostel. A devoted student as well as a public activist, he was an active member of The Dawn Society. It was due to his sense of duty towards his family and education that he refused to join Servants of India Society, as it was during that time when his mother had died as well as his sister became a widow at the age of nineteen and had to return to her parents' home. Prasad was instrumental in the formation of the Bihari Students Conference in 1906 in the hall of Patna College. It was the first organisation of its kind in India and produced important leaders from Bihar like Anugrah Narayan Sinha and Krishna Singh who played a prominent role in the Champaran Movement and Non-cooperation Movement.


title: Rajendra Prasad

text: Prasad served in various educational institutions as a teacher. After completing his M.A in economics, he became a professor of English at the Langat Singh College of Muzaffarpur in Bihar and went on to become the principal. However, later on he left the college to undertake legal studies and entered the Ripon College, Calcutta (now the Surendranath Law College). In 1909, while pursuing his law studies in Kolkata he also worked as Professor of Economics at Calcutta City College.


title: Rajendra Prasad

text: In 1915, Prasad appeared in the examination of master's in law from the Department of Law, University of Calcutta, passed the examination and won a gold medal. He completed his Doctorate in Law from Allahabad University.In 1916, he joined the High Court of Bihar and Odisha. In 1917, he was appointed as one of the first members of the Senate and of the Patna University. He also practised law at Bhagalpur, the famous silk town in Bihar.


title: Rajendra Prasad

text: Prasad had a major role in the Independence Movement. Prasad's first association with Indian National Congress was during 1906 annual session organised in Calcutta, where he participated as a volunteer, while studying in Calcutta. Formally, he joined the Indian National Congress in the year 1911, when the annual session was again held in Calcutta. During the Lucknow Session of Indian National Congress held in 1916, he met Mahatma Gandhi. During one of the fact-finding missions at Champaran, Mahatma Gandhi asked him to come with his volunteers. He was so greatly moved by the dedication, courage and conviction of Mahatma Gandhi that as soon as the motion of Non-Cooperation was passed by Indian National Congress in 1920, he retired from his lucrative career of lawyer as well as his duties in the university to aid the movement.


title: Rajendra Prasad

text: He also responded to the call by Gandhi to boycott Western educational establishments by asking his son, Mrityunjaya Prasad, to drop out of his studies and enrol himself in Bihar Vidyapeeth, an institution he along with his colleagues founded on the traditional Indian model.


title: Rajendra Prasad

text: During the course of the independence movement, he interacted with Rahul Sankrityayan, a writer, and polymath. Rahul Sankrityayan was greatly influenced by Prasad's intellectual powers, finding him to be a guide and guru. In many of his articles he mentioned about his meeting with Sankrityayan and narrated about his meetings with Sankrityayan. He wrote articles for the revolutionary publications Searchlight and the Desh and collected funds for these papers. He toured widely, explaining, lecturing, and exhorting the principles of the independence movement.


title: Rajendra Prasad

text: He took an active role in helping people affected by the 1914 floods that struck Bihar and Bengal. When an earthquake affected Bihar on 15 January 1934, Prasad was in jail. During that period, he passed on the relief work to his close colleague Anugrah Narayan Sinha. He was released two days later and set up Bihar Central Relief Committee on 17 January 1934 and took on the task of raising funds to help the affected people. After the 31 May 1935 Quetta earthquake, when he was forbidden to leave the country due to government's order, he set up the Quetta Central Relief Committee in Sindh and Punjab under his own presidency.


title: Rajendra Prasad

text: He was elected as the President of the Indian National Congress during the Bombay session in October 1934. He again became the president when Subhash Chandra Bose resigned in 1939. On 8 August 1942, Congress passed the Quit India Resolution in Bombay which led to the arrest of many Indian leaders. Prasad was arrested in Sadaqat Ashram, Patna and sent to Bankipur Central Jail. After remaining incarcerated for nearly three years, he was released on 15 June 1945.


title: Rajendra Prasad

text: After the formation of Interim Government of 12 nominated ministers under the leadership of Jawaharlal Nehru on 2 September 1946, he was allocated the Food and Agriculture department. He was elected as the President of Constituent Assembly on 11 December 1946. On 17 November 1947 he became Congress President for a third time after J. B. Kripalani submitted his resignation.


title: Rajendra Prasad

text: Two and a half years after independence, on 26 January 1950, the Constitution of independent India was ratified, and he was elected as the first President of India. Unfortunately, on the night of 25 January 1950 (a day before the Republic Day of India), his sister Bhagwati Devi died. He arranged her cremation but only after his return from the parade ground.


title: Rajendra Prasad

text: As the President of India, Prasad duly acted as required by the Constitution and was independent of any political party. He travelled the world extensively as an ambassador of India, building diplomatic rapport with foreign nations. He was re-elected for two consecutive terms in 1952 and 1957 and is the only President of India to achieve this feat. The Mughal Gardens at the Rashtrapati Bhavan were open to public for about a month for the first time during his tenure, and since then it has been a big attraction for people in Delhi and many other parts of the country.


title: Rajendra Prasad

text: Prasad acted independently off politics, following the expected role of the president as required the constitution. Following the tussle over the enactment of the Hindu Code Bill, he took a more active role in state affairs. In 1962, after serving 12 years as the president, he announced his decision to retire. After relinquishing the office of the President of India in May 1962, he returned to Patna on 14 May 1962 and preferred to stay in the campus of Bihar Vidyapeeth. His wife died on 9 September 1962, a month before Indo-China War. He was subsequently honoured with Bharat Ratna, the nation's highest civilian award.


title: Rajendra Prasad

text: "Babu Rajendra Prasad" is 1980 short documentary film directed by Manjul Prabhat and produced by the Films Division of India which covers the life of the first president of India.


title: Beta blocker

text: Beta blockers, also spelled β-blockers, are a class of medications that are predominantly used to manage abnormal heart rhythms, and to protect the heart from a second heart attack after a first heart attack (secondary prevention). They are also widely used to treat high blood pressure, although they are no longer the first choice for initial treatment of most patients.


title: Beta blocker

text: Beta blockers are competitive antagonists that block the receptor sites for the endogenous catecholamines epinephrine (adrenaline) and norepinephrine (noradrenaline) on adrenergic beta receptors, of the sympathetic nervous system, which mediates the fight-or-flight response. Some block activation of all types of β-adrenergic receptors and others are selective for one of the three known types of beta receptors, designated β, β and β receptors. β-adrenergic receptors are located mainly in the heart and in the kidneys. β-adrenergic receptors are located mainly in the lungs, gastrointestinal tract, liver, uterus, vascular smooth muscle, and skeletal muscle. β-adrenergic receptors are located in fat cells.


title: Beta blocker

text: Beta receptors are found on cells of the heart muscles, smooth muscles, airways, arteries, kidneys, and other tissues that are part of the sympathetic nervous system and lead to stress responses, especially when they are stimulated by epinephrine (adrenaline). Beta blockers interfere with the binding to the receptor of epinephrine and other stress hormones and weaken the effects of stress hormones.


title: Beta blocker

text: In 1964, James Black synthesized the first clinically significant beta blockers—propranolol and pronethalol; it revolutionized the medical management of angina pectoris and is considered by many to be one of the most important contributions to clinical medicine and pharmacology of the 20th century.


title: Beta blocker

text: For the treatment of primary hypertension, meta-analyses of studies which mostly used atenolol have shown that although beta blockers are more effective than placebo in preventing stroke and total cardiovascular events, they are not as effective as diuretics, medications inhibiting the renin–angiotensin system (e.g., ACE inhibitors), or calcium channel blockers.


title: Beta blocker

text: Large differences exist in the pharmacology of agents within the class, thus not all beta blockers are used for all indications listed below.


title: Beta blocker

text: Although beta blockers were once contraindicated in congestive heart failure, as they have the potential to worsen the condition due to their effect of decreasing cardiac contractility, studies in the late 1990s showed their efficacy at reducing morbidity and mortality.


title: Beta blocker

text: Bisoprolol, carvedilol, and sustained-release metoprolol are specifically indicated as adjuncts to standard ACE inhibitor and diuretic therapy in congestive heart failure, although at doses typically much lower than those indicated for other conditions. Beta blockers are only indicated in cases of compensated, stable congestive heart failure; in cases of acute decompensated heart failure, beta blockers will cause a further decrease in ejection fraction, worsening the patient's current symptoms.


title: Beta blocker

text: Beta blockers are known primarily for their reductive effect on heart rate, although this is not the only mechanism of action of importance in congestive heart failure. Beta blockers, in addition to their sympatholytic β1 activity in the heart, influence the renin–angiotensin system at the kidneys. Beta blockers cause a decrease in renin secretion, which in turn reduces the heart oxygen demand by lowering the extracellular volume and increasing the oxygen-carrying capacity of the blood. Heart failure characteristically involves increased catecholamine activity on the heart, which is responsible for several deleterious effects, including increased oxygen demand, propagation of inflammatory mediators, and abnormal cardiac tissue remodeling, all of which decrease the efficiency of cardiac contraction and contribute to the low ejection fraction. Beta blockers counter this inappropriately high sympathetic activity, eventually leading to an improved ejection fraction, despite an initial reduction in ejection fraction.


title: Beta blocker

text: Trials have shown beta blockers reduce the absolute risk of death by 4.5% over a 13-month period. In addition to reducing the risk of mortality, the numbers of hospital visits and hospitalizations were also reduced in the trials.


title: Beta blocker

text: Therapeutic administration of beta blockers for congestive heart failure ought to begin at very low doses (1/8 of target) with a gradual escalation of the dose. The heart of the patient must adjust to decreasing stimulation by catecholamines and find a new equilibrium at a lower adrenergic drive.


title: Beta blocker

text: Officially, beta blockers are not approved for anxiolytic use by the U.S. Food and Drug Administration. However, many controlled trials in the past 25 years indicate beta blockers are effective in anxiety disorders, though the mechanism of action is not known. The physiological symptoms of the fight-or-flight response (pounding heart, cold/clammy hands, increased respiration, sweating, etc.) are significantly reduced, thus enabling anxious individuals to concentrate on the task at hand.


title: Beta blocker

text: Musicians, public speakers, actors, and professional dancers have been known to use beta blockers to avoid performance anxiety, stage fright, and tremor during both auditions and public performances. The application to stage fright was first recognized in "The Lancet" in 1976, and by 1987, a survey conducted by the International Conference of Symphony Orchestra Musicians, representing the 51 largest orchestras in the United States, revealed 27% of its musicians had used beta blockers and 70% obtained them from friends, not physicians. Beta blockers are inexpensive, said to be relatively safe, and on one hand, seem to improve musicians' performances on a technical level, while some, such as Barry Green, the author of "The Inner Game of Music" and Don Greene, a former Olympic diving coach who teaches Juilliard students to overcome their stage fright naturally, say the performances may be perceived as "soulless and inauthentic".


title: Beta blocker

text: Low certainty evidence indicates that the use of beta blockers around the time of cardiac surgery may decrease the risk of heart dysrhythmias and atrial fibrillation. Starting them around the time of other types of surgery, however, may worsen outcomes. For non-cardiac surgery, the use of beta blockers to prevent adverse effects may reduce the risk of atrial fibrillation and myocardial infarctions (very low certainty evidence), however, there is moderate certainty evidence that this approach may increase the risk of hypotension. Low-certainty evidence suggests that beta blockers used perioperatively in non-cardiac surgeries may increase the risk of bradycardia.


title: Beta blocker

text: Because they promote lower heart rates and reduce tremors, beta blockers have been used in professional sports where high accuracy is required, including archery, shooting, golf and snooker. Beta blockers are banned in some sports by the International Olympic Committee. In the 2008 Summer Olympics, 50-metre pistol silver medalist and 10-metre air pistol bronze medalist Kim Jong-su tested positive for propranolol and was stripped of his medals.


title: Beta blocker

text: Adverse drug reactions associated with the use of beta blockers include: nausea, diarrhea, bronchospasm, dyspnea, cold extremities, exacerbation of Raynaud's syndrome, bradycardia, hypotension, heart failure, heart block, fatigue, dizziness, alopecia (hair loss), abnormal vision, hallucinations, insomnia, nightmares, sexual dysfunction, erectile dysfunction and/or alteration of glucose and lipid metabolism. Mixed α/β-antagonist therapy is also commonly associated with orthostatic hypotension. Carvedilol therapy is commonly associated with edema. Due to the high penetration across the blood–brain barrier, lipophilic beta blockers, such as propranolol and metoprolol, are more likely than other less lipophilic beta blockers to cause sleep disturbances, such as insomnia, vivid dreams and nightmares.


title: Beta blocker

text: Adverse effects associated with β-adrenergic receptor antagonist activity (bronchospasm, peripheral vasoconstriction, alteration of glucose and lipid metabolism) are less common with β-selective (often termed "cardioselective") agents, but receptor selectivity diminishes at higher doses. Beta blockade, especially of the beta-1 receptor at the macula densa, inhibits renin release, thus decreasing the release of aldosterone. This causes hyponatremia and hyperkalemia.


title: Beta blocker

text: Hypoglycemia can occur with beta blockade because β2-adrenoceptors normally stimulate glycogen breakdown (glycogenolysis) in the liver and pancreatic release of the hormone glucagon, which work together to increase plasma glucose. Therefore, blocking β2-adrenoceptors lowers plasma glucose. β1-blockers have fewer metabolic side effects in diabetic patients; however, the fast heart rate that serves as a warning sign for insulin-induced low blood sugar may be masked, resulting in hypoglycemia unawareness. This is termed beta blocker-induced hypoglycemia unawareness. Therefore, beta blockers are to be used cautiously in diabetics.


title: Beta blocker

text: A 2007 study revealed diuretics and beta blockers used for hypertension increase a patient's risk of developing diabetes mellitus, while ACE inhibitors and angiotensin II receptor antagonists (angiotensin receptor blockers) actually decrease the risk of diabetes. Clinical guidelines in Great Britain, but not in the United States, call for avoiding diuretics and beta blockers as first-line treatment of hypertension due to the risk of diabetes.


title: Beta blocker

text: Beta blockers must not be used in the treatment of selective alpha-adrenergic agonist overdose. The blockade of only beta receptors increases blood pressure, reduces coronary blood flow, left ventricular function, and cardiac output and tissue perfusion by means of leaving the alpha-adrenergic system stimulation unopposed. Beta blockers with lipophilic properties and CNS penetration such as metoprolol and labetalol may be useful for treating CNS and cardiovascular toxicity from a methamphetamine overdose. The mixed alpha- and beta blocker labetalol is especially useful for treatment of concomitant tachycardia and hypertension induced by methamphetamine. The phenomenon of "unopposed alpha stimulation" has not been reported with the use of beta blockers for treatment of methamphetamine toxicity. Other appropriate antihypertensive drugs to administer during hypertensive crisis resulting from stimulant overdose are vasodilators such as nitroglycerin, diuretics such as furosemide, and alpha blockers such as phentolamine.


title: Beta blocker

text: The 2007 National Heart, Lung, and Blood Institute (NHLBI) asthma guidelines recommend against the use of non-selective beta blockers in asthmatics, while allowing for the use of cardio selective beta blockers.


title: Beta blocker

text: Cardio selective beta blocker (β1 blockers), if really required, can be prescribed at the least possible dose to those with mild to moderate respiratory symptoms. β2-agonists can somewhat mitigate β-Blocker-induced bronchospasm where it exerts greater efficacy on reversing "selective" β-blocker-induced bronchospasm than the "nonselective" β-blocker-induced worsening asthma and/or COPD.


title: Beta blocker

text: Beta blockers' inhibition on epinephrine's effect can somewhat exacerbate hypoglycemia by interfering with glycogenolysis and mask signs of hypoglycemia such as tachycardia, palpitations, diaphoresis, and tremors. Diligent blood glucose level monitoring is necessary for a patient with diabetes mellitus on beta blocker.


title: Beta blocker

text: Unless a pacemaker is present, beta blockers can severely depress conduction in the AV node, resulting in a reduction of heart rate and cardiac output. One should be very cautious with the use of beta blockers in tachycardia patients with Wolff-Parkinson-White Syndrome, as it can result in life-threatening arrhythmia in certain patients. By slowing the conduction through the AV node, preferential conduction through the accessory pathway is favored. If the patient happens to develop atrial flutter, this could lead to a 1:1 conduction with very fast ventricular rate, or worse, ventricular fibrillation in the case of atrial fibrillation.


title: Beta blocker

text: Glucagon, used in the treatment of overdose, increases the strength of heart contractions, increases intracellular cAMP, and decreases renal vascular resistance. It is, therefore, useful in patients with beta blocker cardiotoxicity. Cardiac pacing is usually reserved for patients unresponsive to pharmacological therapy.


title: Beta blocker

text: People experiencing bronchospasm due to the β receptor-blocking effects of nonselective beta blockers may be treated with anticholinergic drugs, such as ipratropium, which are safer than beta agonists in patients with cardiovascular disease. Other antidotes for beta blocker poisoning are salbutamol and isoprenaline.


title: Beta blocker

text: Stimulation of β receptors by epinephrine and norepinephrine induces a positive chronotropic and inotropic effect on the heart and increases cardiac conduction velocity and automaticity. Stimulation of β receptors on the kidney causes renin release. Stimulation of β receptors induces smooth muscle relaxation, induces tremor in skeletal muscle, and increases glycogenolysis in the liver and skeletal muscle. Stimulation of β receptors induces lipolysis.


title: Beta blocker

text: Beta blockers inhibit these normal epinephrine- and norepinephrine-mediated sympathetic actions, but have minimal effect on resting subjects.


title: Beta blocker

text: That is, they reduce the effect of excitement or physical exertion on heart rate and force of contraction, and also tremor, and breakdown of glycogen. Beta blockers can have a constricting effect on the bronchi of the lungs, possibly worsening or causing asthma symptoms.


title: Beta blocker

text: Since β adrenergic receptors can cause vascular smooth muscle dilation, beta blockers may cause some vasoconstriction. However, this effect tends to be small because the activity of β receptors is overshadowed by the more dominant vasoconstricting α receptors. By far the greatest effect of beta blockers remains in the heart. Newer, third-generation beta blockers can cause vasodilation through blockade of alpha-adrenergic receptors.


title: Beta blocker

text: Accordingly, nonselective beta blockers are expected to have antihypertensive effects. The primary antihypertensive mechanism of beta blockers is unclear, but may involve reduction in cardiac output (due to negative chronotropic and inotropic effects). It may also be due to reduction in renin release from the kidneys, and a central nervous system effect to reduce sympathetic activity (for those beta blockers that do cross the blood–brain barrier, e.g. propranolol).


title: Beta blocker

text: Antianginal effects result from negative chronotropic and inotropic effects, which decrease cardiac workload and oxygen demand. Negative chronotropic properties of beta blockers allow the lifesaving property of heart rate control. Beta blockers are readily titrated to optimal rate control in many pathologic states.


title: Beta blocker

text: The antiarrhythmic effects of beta blockers arise from sympathetic nervous system blockade—resulting in depression of sinus node function and atrioventricular node conduction, and prolonged atrial refractory periods. Sotalol, in particular, has additional antiarrhythmic properties and prolongs action potential duration through potassium channel blockade.


title: Beta blocker

text: Blockade of the sympathetic nervous system on renin release leads to reduced aldosterone via the renin–angiotensin–aldosterone system, with a resultant decrease in blood pressure due to decreased sodium and water retention.


title: Beta blocker

text: Also referred to as intrinsic sympathomimetic effect, this term is used particularly with beta blockers that can show both agonism and antagonism at a given beta receptor, depending on the concentration of the agent (beta blocker) and the concentration of the antagonized agent (usually an endogenous compound, such as norepinephrine). See partial agonist for a more general description.


title: Beta blocker

text: Some beta blockers (e.g. oxprenolol, pindolol, penbutolol, labetalol and acebutolol) exhibit intrinsic sympathomimetic activity (ISA). These agents are capable of exerting low-level agonist activity at the β-adrenergic receptor while simultaneously acting as a receptor site antagonist. These agents, therefore, may be useful in individuals exhibiting excessive bradycardia with sustained beta blocker therapy.


title: Beta blocker

text: Agents with ISA should not be used for patients with any kind of angina as it can aggravate or after myocardial infarctions. They may also be less effective than other beta blockers in the management of angina and tachyarrhythmia.


title: Beta blocker

text: Some beta blockers (e.g., labetalol and carvedilol) exhibit mixed antagonism of both β- and α-adrenergic receptors, which provides additional arteriolar vasodilating action.


title: Beta blocker

text: β-selective beta blockers are also known as cardioselective beta blockers. Pharmacologically, the beta-blockade of the B1 receptors in the heart will act on cAMP. The function of cAMP as a second messenger in the cardiac cell is that it phosphorylates the LTCC and the ryanodine receptor to increase intracellular calcium levels and cause contraction. Beta-blockade of the B1 receptor will inhibit cAMP from phosphorylating, and it will decrease the ionotrophic and chronotropic effect. Note that drugs may be cardioselective, or act on B1 receptors in the heart only, but still have instrinsic sympathomimetic activity.


title: Beta blocker

text: Propranolol is the only agent indicated for the control of tremor, portal hypertension, and esophageal variceal bleeding, and used in conjunction with α-blocker therapy in phaeochromocytoma.


title: Beta blocker

text: Beta blockers, due to their antagonism at beta-1 adrenergic receptors, inhibit both the synthesis of new melatonin and its secretion by the pineal gland. The neuropsychiatric side effects of some beta blockers (e.g. sleep disruption, insomnia) may be due to this effect.


title: Beta blocker

text: Some pre-clinical and clinical research suggests that some beta blockers may be beneficial for cancer treatment. However, other studies do not show a correlation between cancer survival and beta blocker usage. Also, a 2017 meta-analysis failed to show any benefit for the use of beta blockers in breast cancer.


title: Beta blocker

text: Beta blockers have also been used for the treatment of schizoid personality disorder. However, there is limited evidence supporting the efficacy of supplemental beta blocker use in addition to antipsychotic drugs for treating schizophrenia.


title: Poe's law

text: Poe's law is an adage of Internet culture saying that, without a clear indicator of the author's intent, any parody of extreme views can be mistaken by some readers for a sincere expression of the views being parodied.


title: Poe's law

text: Poe's law is based on a comment written by Nathan Poe in 2005 on christianforums.com, an Internet forum on Christianity. The message was posted during a debate on creationism, where a previous poster had remarked to another user: "Good thing you included the winky. Otherwise people might think you are serious".


title: Poe's law

text: The original statement of Poe's law referred specifically to creationism, but it has since been generalized to apply to any kind of fundamentalism or extremism.


title: Poe's law

text: Its original conceptualization held that online parodies or sarcasm on religious views are indistinguishable from sincere expressions of religious views. In part, Poe was simply reiterating common advice about the need to clearly mark online sarcasm or parody (e.g. with a smiling or winking emoticon) and that without these unmistakable cues, it would be interpreted as the real thing or used by online trolls, extremists, and/or fundamentalists as sincere expressions of their authors, particularly if they match their own views. As early as 1983, Jerry Schwarz, in a post on Usenet, wrote:


title: Poe's law

text: In 2017, "Wired" published an article calling it "2017's Most Important Internet Phenomenon", and wrote that "Poe's Law applies to more and more internet interactions." The article gave examples of cases involving 4chan and the Trump administration where there were deliberate ambiguities over whether something was serious or intended as a parody, where people were using Poe's law as "a refuge" to camouflage beliefs that would otherwise be considered unacceptable. Some treat Poe's law as part of contemporary kitsch culture; another view maintains that Poe's law could lead to nihilism, a situation where nothing matters and everything is a joke.


title: Boston University

text: Boston University (BU) is a private research university in Boston, Massachusetts. The university is nonsectarian, but has a historical affiliation with the United Methodist Church. It was founded in 1839 by Methodists with its original campus in Newbury, Vermont, before moving to Boston in 1867.


title: Boston University

text: The university now has more than 4,000 faculty members and nearly 34,000 students, and is one of Boston's largest employers. It offers bachelor's degrees, master's degrees, doctorates, and medical, dental, business, and law degrees through 17 schools and colleges on three urban campuses. The main campus is situated along the Charles River in Boston's Fenway-Kenmore and Allston neighborhoods, while the Boston University Medical Campus is located in Boston's South End neighborhood. The Fenway campus houses the Wheelock College of Education and Human Development, formerly Wheelock College, which merged with BU in 2018.


title: Boston University

text: BU is a member of the Boston Consortium for Higher Education and the Association of American Universities. It is classified among "R1: Doctoral Universities – Very High Research Activity". The Boston University Terriers compete in the NCAA Division I. BU athletic teams compete in the Patriot League, and Hockey East conferences, and their mascot is Rhett the Boston Terrier. Boston University is well known for men's hockey, in which it has won five national championships, most recently in 2009.


title: Boston University

text: Among its alumni and current or past faculty, the university counts 8 Nobel Laureates, 23 Pulitzer Prize winners, 10 Rhodes Scholars, 6 Marshall Scholars, 9 Academy Award winners, and several Emmy and Tony Award winners. BU also has MacArthur, Fulbright, and Truman Scholars, as well as American Academy of Arts and Sciences and National Academy of Sciences members, among its past and present graduates and faculty. In 1876, BU professor Alexander Graham Bell invented the telephone in a BU lab.


title: Boston University

text: Boston University traces its roots to the establishment of the Newbury Biblical Institute in Newbury, Vermont, in 1839, and was chartered with the name "Boston University" by the Massachusetts Legislature in 1869. The university organized formal centennial observances both in 1939 and 1969. One or the other, or both dates may appear on various official seals used by different schools of the university.


title: Boston University

text: On April 24–25, 1839, a group of Methodist ministers and laymen at the Old Bromfield Street Church in Boston elected to establish a Methodist theological school. Set up in Newbury, Vermont, the school was named the "Newbury Biblical Institute".


title: Boston University

text: In 1847, the Congregational Society in Concord, New Hampshire, invited the institute to relocate to Concord and offered a disused Congregational church building with a capacity of 1200 people. Other citizens of Concord covered the remodeling costs. One stipulation of the invitation was that the Institute remain in Concord for at least 20 years. The charter issued by New Hampshire designated the school the "Methodist General Biblical Institute", but it was commonly called the "Concord Biblical Institute".


title: Boston University

text: With the agreed twenty years coming to a close, the trustees of the Concord Biblical Institute purchased on Aspinwall Hill in Brookline, Massachusetts, as a possible relocation site. The institute moved in 1867 to 23 Pinkney Street in the Beacon Hill neighborhood of Boston, and received a Massachusetts Charter as the "Boston Theological Seminary".


title: Boston University

text: In 1869, three trustees of the Boston Theological Institute obtained from the Massachusetts Legislature a charter for a university by the name of "Boston University". These trustees were successful Boston businessmen and Methodist laymen, with a history of involvement in educational enterprises, and they became the founders of Boston University. They were Isaac Rich (1801–1872), Lee Claflin (1791–1871), and Jacob Sleeper (1802–1889), for whom Boston University's three West Campus dormitories were later named. Lee Claflin's son, William, was then Governor of Massachusetts and signed the University Charter on May 26, 1869, after it was passed by the Legislature.


title: Boston University

text: As reported by Kathleen Kilgore in her book "Transformations, A History of Boston University" (see Further reading), the founders directed the inclusion in the Charter of the following provision, unusual for its time:


title: Boston University

text: Every department of the new university was also open to all on an equal footing regardless of sex, race, or (with the exception of the School of Theology) religion.


title: Boston University

text: The Boston Theological Institute was absorbed into Boston University in 1871 as the BU School of Theology.


title: Boston University

text: On January 13, 1872, Isaac Rich died, leaving the vast bulk of his estate to a trust that would go to Boston University after ten years of growth while the university was organized. Most of this bequest consisted of real estate throughout the core of the city of Boston, which was appraised at more than $1.5 million. Kilgore describes this as the largest single donation to an American college or university as of that time. By December, however, the Great Boston Fire of 1872 had destroyed all but one of the buildings Rich had left to the university, and the insurance companies with which they had been insured were bankrupt. The value of his estate, when turned over to the university in 1882, was half what it had been in 1872.


title: Boston University

text: As a result, the university was unable to build its contemplated campus on Aspinwall Hill, and the land was sold piecemeal as development sites. Street names in the area, including Claflin Road, Claflin Path, and University Road, are the only remaining evidence of university ownership in this area. Following the fire, Boston University established its new facilities in buildings scattered throughout Beacon Hill, and later expanded into the Boylston Street and Copley Square area, before building its Charles River Campus in the 1930s.


title: Boston University

text: After receiving a year's salary advance to allow him to pursue his research in 1875, Alexander Graham Bell, then a professor at the school, invented the telephone in a Boston University laboratory. In 1876, Borden Parker Bowne was appointed professor of philosophy. Bowne, an important figure in the history of American religious thought, was an American Christian philosopher and theologian in the Methodist tradition. He is known for his contributions to personalism, a philosophical branch of liberal theology. The movement he led is often referred to as Boston Personalism.


title: Boston University

text: The university continued its tradition of openness in this period. In 1877, Boston University became the first American university to award a PhD to a woman, when classics scholar Helen Magill White earned hers with a thesis on "The Greek Drama". Then in 1878 Anna Oliver became the first woman to receive a degree in theology in the United States, but the Methodist Church would not ordain her. Lelia J. Robinson, who graduated from the university's law school in 1881, became the first woman admitted to the bar in Massachusetts. Solomon Carter Fuller, who graduated from the university's School of Medicine in 1897, became the first black psychiatrist in the United States and would make significant contributions to the study of Alzheimer's disease.


title: Boston University

text: Seeking to unify a geographically scattered school and enable it to participate in the development of the city, school president Lemuel Murlin arranged that the school buy the present campus along the Charles River. Between 1920 and 1928, the school bought the of land that had been reclaimed from the river by the Riverfront Improvement Association. Plans for a riverside quadrangle with a Gothic Revival administrative tower modeled on the "Old Boston Stump" in Boston, England were scaled back in the late 1920s when the State Metropolitan District Commission used eminent domain to seize riverfront land for Storrow Drive. Murlin was never able to build the new campus, but his successor, Daniel L. Marsh, led a series of fundraising campaigns (interrupted by both the Great Depression and World War II) that helped Marsh to achieve his dream and to gradually fill in the university's new campus. By spring 1936, the student body included 10,384 men and women.


title: Boston University

text: In 1951, Harold C. Case became the school's fifth president and under his direction the character of the campus changed significantly, as he sought to change the school into a national research university. The campus tripled in size to , and added 68 new buildings before Case retired in 1967. The first large dorms, Claflin, Rich and Sleeper Halls in West Campus were built, and in 1965 construction began on 700 Commonwealth Avenue, later named Warren Towers, designed to house 1800 students. Between 1961 and 1966, the BU Law Tower, the George Sherman Union, and the Mugar Memorial Library were constructed in the Brutalist style, a departure from the school's traditional architecture. The College of Engineering and College of Communication were housed in a former stable building and auto-show room, respectively. Besides his efforts to expand the university into a rival for Greater Boston's more prestigious academic institutions, such as Harvard University and the Massachusetts Institute of Technology (both in Cambridge across the Charles River from the BU campus), Case involved himself in the start of the student/societal upheavals that came to characterize the 1960s.


title: Boston University

text: When a mini-squabble over editorial policy at college radio WBUR-FM – whose offices were under a tall radio antenna mast in front of the School of Public Relations and Communications (later College of Communications) – started growing in the spring of 1964, Case persuaded university trustees that the university should take over the widely-heard radio station (now a major outlet for National Public Radio and still a BU-owned broadcast facility). The trustees approved the firing of student managers and clamped down on programming and editorial policy, which had been led by Jim Thistle, later a major force in Boston's broadcast news milieu. The on-campus political dispute between Case's conservative administration and the suddenly active and mostly liberal student body led to other disputes over BU student print publications, such as the "B.U. News" and the "Scarlet", a fraternity association newspaper.


title: Boston University

text: The Presidency of John Silber also saw much expansion of the campus and programs. In the late 1970s, the Lahey Clinic vacated its building at 605 Commonwealth Avenue and moved to Burlington, Massachusetts. The vacated building was purchased by BU to house the School of Education. After arriving from the University of Texas in 1971, Silber set out to remake the university into a global center for research by recruiting star faculty. Two of his faculty "stars", Elie Wiesel and Derek Walcott, won Nobel Prizes shortly after Silber recruited them. Two others, Saul Bellow and Sheldon Glashow won Nobel Prizes before Silber recruited them.


title: Boston University

text: In addition to recruiting new scholars, Silber expanded the physical campus, constructing the Photonics Center for the study of light, a new building for the School of Management, and the Life Science and Engineering Building for interdisciplinary research, among other projects. Campus expansion continued in the 2000s with the construction of new dormitories and the Agganis Arena.


title: Boston University

text: To protest the poor condition of Boston University's African-American curriculum, on April 25, 1968 (three weeks after the assassination of Martin Luther King Jr.), African-American students conducted a sit-in and locked BU President Dr. Arland F. Christ-Janer out of his office for 12 hours. Umoja, BU's Black Student Union, put forward ten demands to Dr. Christ-Janer and got nine of them approved that included the creation of a Martin Luther King Chair of Social Ethics, expansion of African-American library resources and tutoring services, opening an "Afro-American coordinating center," admission and selection of more Black students and faculty. No disciplinary action was taken against the students who only opened the chains after their demands were met. "There was no surprise, or feeling of victory on the students' parts," said Dr. Christ-Janer in response to the sit-in. "They had confidence in their demands, and I had a confidence in them. The university, black and white alike, was the winner."


title: Boston University

text: The late twentieth century saw a culmination in student activism at Boston University during the presidency of John R. Silber. In 1972, student protests rose against the university administration's endorsement of Marine Corps recruitment on campus which faced significant opposition from the Student Democratic Society. On March 27, 1972, 50 police officers in "riot gear" defused a demonstration of 150 protesters at 195 Bay State Road, the BU Placement Office, where Marine recruiters were holding student interviews. A few protesters were arrested while some sustained minor injuries, including a student and two officers. Contrary to student claims of a peaceful protest, Silber said, "Civilization doesn't abdicate in face of barbarism. Those students or nonstudents who deliberately seek violent confrontation and refuse all efforts at peaceful resolution of issues must expect society to use its police power in its own defense." In response to Silber's decision of a forceful police intervention, the Faculty State conducted a vote on Silber's resignation which could not pass due to a "vote of 140-25 with 32 abstentions." As a result of this failed motion, Peter P. Gabriel resigned his position as the dean of Boston University's School of Management in protest of Silber's presidency and his "counterproductive" leadership. Silber's support of military recruitment on campus, which he pushed to make the university eligible for Federal grants, caused other demonstrations. On December 5, 1972, fifteen BU Student Government officers started a three-day hunger strike at Marsh Chapel demanding Silber "to file a lawsuit against the Federal government challenging the constitutionality of the Herbert Amendment."


title: Boston University

text: On March 16, 1978, about 900 Boston University students gathered at the George Sherman Union to protest against the $400 rise in tuition and $150 rise in housing charges declared by the trustees on March 7. The protest interrupted a board of trustees conference. While John Silber and Arthur G.B. Metcalf, the chairman of the board of trustees, were negotiating with student government representatives to discuss the matter further on a separate occasion, the protesters marched into the building from two entrances, effectively trapping 40 trustees and 10 university administrators in the building for over thirty minutes. Twenty officers from the Boston University Police Department had to disperse the crowd from the stairwells. The protest resulted in the arrest of 19 year old Joshua Grossman, while another student and two BUPD officers were taken to hospitals.


title: Boston University

text: On April 5, 1979, several hundred faculty members, as well as clerical workers and librarians, went on strike. The faculty members were seeking a labor contract while the clerical workers and librarians were seeking union recognition. The strike ended by mid-April under terms favorable to the employees.


title: Boston University

text: On November 27, 1979, the committee to Defend Iranian Students- composed of Iranian students, Youths Against Foreign Fascism and the Revolutionary Communist Party, held a demonstration at the George Sherman Union against the deposed Shah of Iran and the deportation of Iranian students from the US. "To the Iranian people, that man (the shah) is Adolf Hitler," students protested. "The Shah Must Face the Wrath of the People." This was met with chants of "God Bless America" from the opposing group. Twenty policemen broke up the confronting parties though no arrests were made.


title: Boston University

text: Robert A. Brown's presidency, which started in 2005, has sought to further the consolidation of campus infrastructure that was commenced by earlier administrations. During his tenure, Brown has strengthened the core missions of undergraduate, graduate, and professional education, interdisciplinary work, and research and scholarship across all 17 schools and colleges.


title: Boston University

text: In 2012, the university was invited to join the Association of American Universities, comprising 66 leading research universities in the United States and Canada. BU, one of four universities at the time invited to join the group since 2000, became the 62nd member. In the Boston area, Harvard, MIT, Tufts, and Brandeis are also members.


title: Boston University

text: That same year, a $1 billion fundraising campaign was launched, its first comprehensive campaign, emphasizing financial aid, faculty support, research, and facility improvements. In 2016, the campaign goal was reached. The Board of Trustees voted to raise the goal to $1.5 billion and extend through 2019. The campaign has funded 74 new faculty positions, including 49 named full professorships and 25 Career Development Professorships. The campaign concluded in September 2019, raising a total of $1.85 billion over seven years.


title: Boston University

text: In February 2015 the faculty adopted an open-access policy to make its scholarship publicly accessible online.


title: Boston University

text: In 2016, "Times Higher Education (THE)" named Boston University to a list of 53 "international powerhouse" institutions, schools that have the best chance of being grouped alongside—or ahead of—"THE" most elite global "old stars", a group that includes the University of Oxford, Stanford, Harvard, Yale, MIT, and Princeton.


title: Boston University

text: The Charles River and Medical Campuses have undergone physical transformations since 2006, from new buildings and playing fields to dormitory renovations. The campus has seen the addition of a 26-floor student residence at 33 Harry Agganis Way, nicknamed StuVi2, the New Balance Playing Field, the Yawkey Center for Student Services, the Alan and Sherry Leventhal Center, the Law tower and Redstone annex, the Engineering Product Innovation Center (EPIC), the Rajen Kilachand Center for Integrated Life Sciences & Engineering, and the Joan and Edgar Booth Theatre, which opened in fall 2017. The construction of the Rajen Kilachand Center for Integrated Life Sciences & Engineering was funded by part of BU's largest ever gift, a $115 million donation from Rajen Kilachand. The Dahod Family Alumni Center in the renovated BU Castle began in May 2017 and was completed in fall 2018. Development of the university's existing housing stock has included significant renovations to BU's oldest dorm, Myles Standish Hall and Annex, and to Kilachand Hall, formerly known as Shelton Hall, and a brand new student residence on the Medical Campus.


title: Boston University

text: In 2019, Boston University expanded its financial aid program so that it would "meet the full need for all domestic students who qualify for financial aid," starting in fall 2020.


title: Boston University

text: In September 2022, Robert A. Brown announced he will step down at the end of the 2022–2023 academic year. Brown began his presidency in September 2005, and his contract was set to run through 2025.


title: Boston University

text: The university closed down due to the COVID-19 pandemic and shifted to online learning for the remainder of the semester on March 11, 2020. For the fall 2020 semester, BU offered a hybrid system that allows for students to decide whether to take a remote class or participate in-person. Larger classes would be broken down into smaller groups that rotate between online and in-person sessions. The school started administering its own COVID-19 testing for faculty, staff, and students on July 27, 2020. The new BU Clinical Testing Laboratory has accelerated testing that can give results to students, staff, and faculty by the next day. The lab uses eight robots to process up to 6,000 tests per day. A contact tracing team is part of the process to contain infections on campus. BU also started a new website "Back2BU" to provide students with the latest information on reopening.


title: Boston University

text: BU's National Emerging Infectious Diseases Laboratories (NEIDL) has been working with live coronavirus samples since March 2020, and—at the time—was the only New England lab to have live samples.


title: Boston University

text: In August 2020, BU filed a service mark application with the United States Patent and Trademark Office to secure the phrase "F*ck It Won't Cut It" for a student-led COVID-19 safety program on campus. The slogan is meant to promote "safe and smart actions and behaviors for college and university students in a COVID-19 environment", according to the application.


title: Boston University

text: In July 2021, BU announced faculty and staff will be required to be vaccinated against COVID-19 for the fall 2022 semester. This comes after a vaccine requirement for all students, which was announced in April.


title: Boston University

text: In October 2022, Boston University's National Emerging Infectious Diseases Laboratories conducted research in a Biosafety Level 3 lab that modified the original strain of the virus that causes COVID-19 with the spike proteins of the Omicron variant. This resulted in a virus that was more lethal to lab mice than the Omicron variant itself, but less lethal than the original strain. Some medical authorities criticized the research as dangerous "gain of function" research, but others argued that it did not "technically" count as gain of function research because the modified virus happened not to be quite as lethal as the original strain. Marc Lipsitch of Harvard, however, argued "these are unquestionably gain-of-function experiments. As many have noted, this is a very broad term encompassing many harmless and some potentially dangerous experiments. GOF is a scientific technique, not an epithet." While the BU researchers gained internal research and Boston government approvals for the research, they failed to notify the US Government's National Institute of Allergy and Infectious Diseases that was a funder of the lab.


title: Boston University

text: The university's main Charles River Campus follows Commonwealth Avenue and the Green Line, beginning near Kenmore Square and continuing for over a mile and a half to its end near the border of Boston's Allston neighborhood. The Boston University Bridge over the Charles River into Cambridge represents the dividing line between Main Campus, where most schools and classroom buildings are concentrated, and West Campus, home to several athletic facilities and playing fields, the large West Campus dorm, and the new John Hancock Student Village complex.


title: Boston University

text: The main campus buildings of BU are separated from the Charles River Esplanade parkland and the Paul Dudley White Bike Path along the banks of the nearby Charles River, by heavily trafficked Storrow Drive, a high-speed limited-access major roadway connecting downtown Boston to its western suburbs. The separation occurred in the late 1920s, when the Commonwealth of Massachusetts seized land by eminent domain for the construction of the new roadway along the riverbank. A narrow strip of grassy lawn between BU academic buildings lining Commonwealth Avenue and the torrent of traffic on Storrow Drive has been humorously dubbed "BU Beach", because it is a favorite hangout for sunbathing in good weather. The lounging students are protected from traffic incursions by a raised earthen berm, which also muffles the traffic noise to a dull roar. To protect pedestrians from vehicular collisions, Storrow Drive is enclosed by fencing, with pedestrian bridges allowing safe crossings at Silber Way and at Marsh Chapel. An additional crossing is possible at the BU Bridge, which also allows street traffic to cross from the Boston side to the Cambridge side of the Charles River.


title: Boston University

text: As a result of its continual expansion, the Charles River campus contains an array of architecturally diverse buildings. The College of Arts and Sciences, Marsh Chapel, and the School of Theology buildings are the university's most recognizable, and were built in the late-1930s and 1940s in collegiate gothic style. A sizable amount of the campus is traditional Boston brownstone, especially at Bay State Road and South Campus, where BU has acquired almost every townhouse those areas offer. The buildings are primarily dormitories, but many also serve as various institutes as well as department offices.


title: Boston University

text: From the 1960s–1980s many contemporary buildings were constructed, including the Mugar Library, BU Law School, and Warren Towers, all of which were built in the brutalist style of architecture. The Metcalf Science Center for Science and Engineering, constructed in 1983, might more accurately be described as Structural Expressionism. Morse Auditorium, adjacent, stands in stark architectural contrast, as it was originally constructed as a Jewish synagogue. The most recent architectural additions to BU's campus are the Photonics Center, Life Science and Engineering Building, The Student Village (which includes the FitRec Center and Agganis Arena), and the Questrom School of Business. All these buildings were built in brick, a few with a substantial amount of brownstone. Boston University converted the old Nickelodeon Cinemas complex into College of Engineering labs and offices. In 2016, the university sold the building that housed the Huntington Theatre Company and constructed the Joan & Edgar Booth Theatre and College of Fine Arts Production Center to consolidate the theater program on campus.


title: Boston University

text: BU has earned several historic preservation awards with recent extensive building renovation projects, such as the School of Law tower, the Alan & Sherry Leventhal Center, Myles Standish Hall, and the Dahod Family Alumni Center (formerly The Castle). Construction of the brick and glass Yawkey Center for Student Services was designed to follow the requirements of the Bay State Road historic district. Use of glass and steel for new construction on Commonwealth Avenue includes the Rajen Kilachand Center for Integrated Life Sciences & Engineering, which opened in 2017, and the 19-story Center for Computing & Data Sciences, which is due to open in 2022.


title: Boston University

text: In 2018, following negotiations in the preceding year, Boston University purchased the former Wheelock College, which is now referred to as the Boston University Fenway Campus (although it is actually located in the adjacent neighborhood of Longwood).


title: Boston University

text: , BU has sold or leased to real estate developers several building sites it owned in Kenmore Square next to its campus. Large multistory buildings are being constructed there, which will transform the long-time appearance of the busy traffic hub.


title: Boston University

text: In September 2021, BU completed a $115 million project to renovate and expand the Henry M. School of Dental Medicine. The project expanded clinical spaces, added a simulation learning center, and improved collaborative spaces for students.


title: Boston University

text: Boston University's housing system is the nation's 10th largest among four-year colleges. BU was originally a commuter school, but the university now guarantees the option of on-campus housing for four years for all undergraduate students. Currently, 76 percent of the undergraduate population lives on campus. Boston University requires that all students living in dormitories be enrolled in a year-long meal plan with several combinations of meals and dining points which can be used as cash in on-campus facilities.


title: Boston University

text: Housing at BU is an unusually diverse melange, ranging from individual 19th-century brownstone townhouses and apartment buildings acquired by the school to large-scale high-rises built in the 1960s and 2000s.