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Uveitis is inflammation of the uvea, which is made up of the iris, ciliary body and choroid. Together, these form the middle layer of the eye between the retina and the sclera (white of the eye). The eye is shaped like a tennis ball, with three different layers of tissue surrounding the central gel-filled cavity, which is called the vitreous. |
The innermost layer is the retina, which senses light and helps to send images to your brain. The outermost layer is the sclera, the strong white wall of the eye. The middle layer between the sclera and retina is called the uvea. The uvea contains many blood vessels — the veins, arteries and capillaries — that carry blood to and |
from the eye. Because the uvea nourishes many important parts of the eye (such as the retina), inflammation of the uvea can damage your sight. There are several types of uveitis, defined by the part of the eye where it occurs. - Iritis affects the front of your eye. Also called anterior uveitis, this is the most common type of |
uveitis. Iritis usually develops suddenly and may last six to eight weeks. Some types of anterior uveitis can be chronic or recurrent. - If the uvea is inflamed in the middle or intermediate region of the eye, it is called pars planitis (or intermediate uveitis). Episodes of pars planitis can last between a few weeks to years. The disease goes |
through cycles of getting better, then worse. - Posterior uveitis affects the back parts of your eye. Posterior uveitis can develop slowly and often lasts for many years. - Panuveitis occurs when all layers of the uvea are inflamed. Next Page: Uveitis Causes |
The National Cattlemen's Beef Association has criticized a review of the National Ambient Air Quality Standards for Particulate Matter. Conducted by the U.S. Environmental Protection Agency, the study was done as part of a required review of the coarse particulate matter standards. In effect, EPA is looking at the impact |
of duct. According to a statement from NCBA, coarse particulate matter is "nothing more than dust kicked up by cars and trucks traveling on dirt roads, a tractor tilling a field or cattle moving around on dirt," says Tamara Theis, NCBA's chief environmental council. "Studies do not show that rural |
dust is a health problem." EPA, back in 2006, set a coarse particulate matter standard of 150 micrograms per cubic meter of air, and when reviewing the standard in 2008, determined that the evidence on health effects from this level of dust was inconclusive. However, in July 2009, EPA reinterpreted |
what NCBA calls "the inconclusive evidence" and made use of what the group calls a flawed study to suggest that there are adverse health effects from dust at leves that are 10 times lower than the current standard. Theis says EPA is suggesting 12 to 15 micrograms of dust per |
cubic meter of air, which is below the naturally occurring levels of dust through most Western states - including "pristine National Parks," she says. If EPA were to set air standards at this level, much of the country would be over the limit. Cattle producers are concerned because it would |
limit the ability to raise livestock, but the issue goes beyond agriculture, Theis says. "States would be required to impose extreme control requirements and limitations on many businesses to ensure that the standard is met." The group is urging EPA to reject the study results and refrain from tightening the |
Grain farmers could make more money be switching to organic grain crops according to a new study released at last week's American Agricultural Economics Association's annual meeting. Records showed that organic crops fetched much more than conventional crops: soybeans, up to $14 more per bushel; corn, up to $3 more; and wheat, up to $5 more. Organic alfalfa hay is |
too new to have a track record, so researchers recorded it as selling for the same price as conventionally grown hay. Over four years the study analyzed both economic risks and transition effects of switching to organic farming of the Agricultural Research Service's Swan Lake Research Farm near Morris, Minn. The 130-acre Swan Lake farm is representative of typical corn-soybean |
farms in Minnesota. ARS economist David Archer and soil scientist Hillarius Kludze compared an organic corn-soybean rotation and an organic corn-soybean-spring wheat/alfalfa rotation - half grown with conventional tillage and half with strip tillage - with a corn-soybean rotation using conventional tillage. Strip tillage involves tilling only the middle of the seedbed. The scientists found that when strip tillage is |
used with organic farming, one of the transition risks is an increase in weeds until farmers learn to manage the system. Computer simulations projected costs, yields and risks over a 20-year period, using yield and economic data from the four-year study, as well as crop price records of recent years. Another computer model projected that farmers would net an average |
$50 to $60 more per acre a year by going organic, even with the highest transition costs. The premium price advantage would outweigh the initial higher costs and possibly lower yields, even if organic prices were to drop by half. |
2; //foo = 1 (the two gets removed) Number literals define the number value. In particular: They appear as a set of digits of varying length. Negative literal numbers have a minus sign before the set of digits. Floating point |
literal numbers contain one decimal point, and may optionally use the E notation with the character e. An integer literal may be prepended with "0", to indicate that a number is in base-8. (8 and 9 are not octal digits, |
and if found, cause the integer to be read in the normal base-10). An integer literal may also be found with "0x", to indicate a hexadecimal number. The Math Object Unlike strings, arrays, and dates, the numbers aren't objects. The |
Math object provides numeric functions and constants as methods and properties. The methods and properties of the Math object are referenced using the dot operator in the usual way, for example: var varOne = Math.ceil(8.5); var varPi = Math.PI; var |
sqrt3 = Math.sqrt(3); Methods random() Generates a pseudo-random number. var myInt = Math.random(); max(int1, int2) Returns the highest number from the two numbers passed as arguments. var myInt = Math.max(8, 9); document.write(myInt); //9 min(int1, int2) Returns the lowest number from |
by +Richard Holbrooke – Schwann cells boost and amplify nerve growth in animal models, but their clinical use has been held back because they are difficult, time-consuming and costly to |
culture. A University of Sheffield team, led by Professor John Haycock, has developed a new technique with adult rat tissue which overcomes all these problems, producing Schwann cells in less |
than half the time and at much lower cost. “The ability of Schwann cells to boost nerve growth was proved many years ago in animals, but if you want to |
use this technique with patients, the problem is: where do you get enough cells from?” said Professor Haycock, from the University’s Department of Materials Science and Engineering. “To reduce immune |
rejection, the cells have to be grown from the patient’s own tissue. Of course, you want to take the smallest amount of tissue necessary, so the technique must be efficient. |
It must also be fast, so treatment can begin as soon as possible after injury. For clinical use, it must also provide pure Schwann cells. And finally, to make it |
viable, it has to be at a reasonable cost.” Existing methods for growing Schwann cells from adult tissue promote the growth of another type of cell, called fibroblasts, which swamp |
the Schwann cells, reducing the speed they grow and their numbers. This means that large amounts of tissue are needed at the outset, to grow sufficient cells for therapeutic use. |
It also requires extra purification stages added to the process, making it slow and costly – taking up to 3 months to complete. Professor Haycock and his team have come |
up with a very simple solution: feed the Schwann cells but starve the fibroblasts. The research, published today in Nature Protocols, uses an amino acid that only the Schwann cells |
can break down and feed off, and are able to produce a 97 per cent pure population of Schwann cells in a much shorter space of time – just 19 |
days – from a small sample of adult tissue. Professor Haycock is confident the technique can be replicated in humans. His team are trialling the same method using human nerve |
LANs to WANs(c) The Complete Management Guide Authors: Muller N.J. Published year: 2003 |< Day Day Up >| Depending on the situation facing network managers, bridges can be used to either extend or segment LANs. At one level, bridges can be used for segmenting LANs into smaller subnets to improve |
performance, control access, and facilitate fault isolation and testing without impacting the overall user population. At another level, they are used to create an extended network that greatly expands the number of devices that can be supported and the services available to each user . Bridges may even offer additional |
features such as data compression, which has the effect of providing greater throughput over low-speed lines. Compression ratios of 2:1 all the way down to 6:1 may be selected by the network manager, depending on what the vendor offers with a specific product. As noted, bridging occurs at the data |
link layer (see Figure 5.1), which provides physical addressing, manages access to the physical medium, controls data flow, and handles transmission errors. Bridges analyze incoming frames, make forwarding decisions based on the source and destination addresses of those frames, and then forward the frames to their destinations. Sometimes, as in |
source-route bridging, the frame contains the entire path to the destination. In other cases, as in transparent bridging, frames are forwarded one hop at a time toward the destination. Figure 5.1: Bridge functionality in reference to the OSI model. Bridges can be either local or remote. Local bridges provide direct |
connections between many LAN segments in the same area. Remote bridges connect LAN segments in different areas, usually over telecommunication lines. There are several kinds of bridging and all may be supported in the same device: Transparent bridging —used mostly in Ethernet environments that have the same media types, these |
bridges keep a table of destination addresses and outbound interfaces. Source-route bridging —used mostly in token-ring environments, these bridges only forward frames based on the routing indicator contained in the frame. End stations are responsible for determining and maintaining the table of destination addresses and routing indicators. Translation bridging —used |
to bridge data between different media types, these devices typically go between Ethernet and FDDI or token ring to Ethernet. Source-route translation bridging —this is a combination of source-route bridging and transparent bridging that allows communication in mixed Ethernet and token-ring environments. (Translation bridging without routing indicators between token ring |
and Ethernet is also called source-route transparent bridging.) The engine for transparent bridging is the spanning tree algorithm (STA), which dynamically discovers a loop-free subset of the network’s topology. The STA accomplishes this by placing active bridge ports that create loops into a standby or blocked condition. A blocked port |
can provide redundancy in that if the primary port fails, it can be activated to take the traffic load. The spanning tree calculation is triggered when the bridge is powered up and whenever a change in topology is detected . A topology change might occur when a forwarding port is |
going down (blocking) or when a port transitions to forwarding and the bridge has a designated port, which also indicates that the bridge is not standalone. Configuration messages known as bridge protocol data units (BPDUs) actually trigger the spanning tree calculation. These messages are exchanged between bridges at regular intervals |
set by the network manager, usually 1 to 4 seconds. Once a change in topology is detected, this information must be shared with all bridges on the network. This is a two-step process that starts when a bridge notifies the root bridge of the spanning tree by sending it a |
special BPDU known as a topology change notification (TCN). The bridge sends the TCN out over its root port. The root bridge acknowledges the message by sending back a normal configuration BPDU with the topology change acknowledgment (TCA) bit set. The second step in the topology update process entails the |
root bridge sending out configuration BPDUs with the topology change (TC) bit set. These BPDUs are relayed by every bridge, so they can become aware of the changed topology. There are some problems associated with spanning tree. The more hosts on the network, the higher the probability of topology changes. |
For example, a directly attached host, such as a client or server, will trigger a topology change when powered off, then go on to clear an operating system problem. In a large, flat network, the point can be reached when it is continually in topology change status. The resulting high |
level of flooding can lead to an unstable STP environment. To deal with this problem, vendors have come up with ways to avoid TCN generation for certain events. For example, the network manager can configure the bridge so that it issues a TCN when a server is power cycled, but |
not when client devices are power cycled. If a bridge port going up or down is not deemed an important event, this event too can be programmed not to issue a TCN. Source-route bridging (SRB) is used in the token-ring environment as the method by which a station establishes a |
route through a multiple-ring network to its destination. The first step for a station to reach another is to create a packet called an explorer. This packet is copied by all bridges in the network, with each of them adding information about itself before passing it on. The explorer packet’s |
routing information field (RIF) contains the information of where it has traversed through the network and within the RIF; a route descriptor stores the path it has taken through the network. As the explorer packet is constructed on its way through the network, the destination station will start receiving data |
packets from the originating station. Based on the contents of the explorer packet, the destination station will then decide which route to use to send data packets back to the originating station. Or it will send its own explorer packet so that the originating station can determine its own route. |
The explorer packet is limited in terms of how many rings it can hold in the routing information field. Although the RIF can hold a total of 14 rings, IBM long ago limited this to seven. Other vendors also adopted this limitation. Consequently, an explorer packet that has traversed seven |
rings will be dropped in the network. To control traffic in the network with more precision, parameters can be set in the bridge to decrease this number even further, so that packets that reach X number of rings (any number below seven) will be dropped. While explorers are limited to |
traversing only seven rings, in a meshed ring environment, one explorer can finish being copied by many bridges, which can cause too many explorers. Explorer storms can be prevented in redundant network topologies by setting the bridge to filter out explorers that have already been forwarded once. Since explorer traffic |
can be distinguished from regular source route traffic, the network manager can issue commands that check the bridge for various parameters, such as the number of explorers that were dropped outbound on that interface. While Ethernet has become the network of choice for new installations, there is still a good |
amount of token ring in use, making it necessary to mix the two environments for data exchange. Doing so is complicated because some very fundamental differences between Ethernet and token ring must be reconciled. Token ring has functional addresses, while Ethernet primarily relies on broadcasts. Furthermore, MAC addresses on the |
Ethernet are different from MAC addresses on the token ring. Ethernet does not have a source-route bridging capability and token ring has a routing information field. Finally, token ring and Ethernet use different methods to read the bits into their adapters. To unify the two environments, vendors have come up |
with various methods such as translation bridging. This is a type of bridging that is implemented on networks that use different MAC sublayer protocols, providing a method of resolving differences in header formats and protocol specifications. Since there are no real standards in how communication between two media types should |
occur, however, no single translation implementation can be called correct. The only consideration for network managers is to select a method of translation and implement it uniformly throughout the network. Essentially, the bridges reorder source and destination address bits when translating between Ethernet and token-ring frame formats. The problem of |
embedded MAC-addresses can be resolved by programming the bridge to look for various types of MAC addresses. Some translation-bridges simply check for the most popular embedded addresses. If others are used, the bridge must be programmed to look for them as well. But if translation-bridging software runs in a multi-protocol |
router, which is very common today, these protocols can be routed and the problem avoided entirely. Token ring’s RIF field has a component that indicates the largest frame size that can be accepted by a particular source-route bridging implementation. Translation bridges that send frames from the transparent-bridging domain to the |
SRB domain usually set the maximum transfer unit (MTU) field to 1,500 bytes to limit the size of token-ring frames entering the transparent-bridging domain, because this is the maximum size of Ethernet frames. Some hosts cannot process this field correctly, in which case translation bridges are forced to drop the |
frames that exceed Ethernet’s MTU size. Bits representing token-ring functions that are absent in Ethernet are discarded by translation bridges. For example, token ring’s priority, reservation, and monitor bits are discarded during translation. And token ring’s frame status bits are treated differently, depending on the bridge manufacturer; the products of |
some manufacturers may even ignore these bits. Sometimes, the bridge will have the C bit set, indicating that the frame has been copied, but not the A bit set, indicating that the destination station recognizes the address. In the former case, a token-ring source node determines if the frame it |
sent has become lost. Advocates of this approach claim that reliability mechanisms, such as the tracking of lost frames, are better left for implementation in Layer 4 of the OSI model. Advocates of setting the C bit argue that this bit must be set to track lost frames, but that |
the A bit cannot be set because the bridge is not the final destination. Translation bridges also can be used to create a software gateway between the token ring and Ethernet domains. To the SRB end stations, the translation bridge has a ring number and a bridge number associated with |
it, so it looks like a standard source-route bridge. In this case, the ring number reflects the entire transparent-bridging domain. To the transparent-bridging domain, the translation bridge is just another transparent bridge. When bridging from the SRB domain to the transparent-bridging domain, SRB information is removed. Token ring’s routing information |
fields usually are cached for use by any subsequent return traffic. When bridging from the transparent bridging to the SRB domain, the translation bridge checks the frame to see if it has a multicast or unicast destination. If the frame has a multicast or broadcast destination, it is sent into |
the SRB domain as a spanning-tree explorer. If the frame has a unicast address, the translation bridge looks up the destination in the RIF cache. If a path is found, it is used and the RIF information is added to the frame; otherwise , the frame is sent as a |
spanning-tree explorer. Another solution to unify the Ethernet and token-ring environments is source-route translation bridging (SRTLB). This entails the addition of bridge groups to the interfaces of both the token ring and Ethernet bridges to create a transparent bridge domain between the two environments. The bridges at each end are |
responsible for establishing the path through the network. When a bridge on a token ring receives a packet from an Ethernet, for example, path establishment is handled as follows (see Figure 5.2): Figure 5.2: Source-route translation bridging, from token ring to Ethernet. Bridge-1 receives a packet from the Ethernet. This |
is from PC-1 to the host. Bridge-1 needs a RIF to reach the host, so it creates an explorer to learn the path to reach the host. After Bridge-1 receives the response, it sends the response (without a RIF) to the Ethernet station. PC-1 sends an exchange identifier (XID) to |
the host MAC address. Bridge-1 gets the Ethernet packet, attaches the RIF to the host, and sends the packet on its way. As far as the host is concerned , the Ethernet is sitting on a pseudo ring. This is configured with the source-bridge transparent command on the bridge. The |
pseudo ring makes the host treat the Ethernet as if it were a token ring. |< Day Day Up >| LANs to WANs(c) The Complete Management Guide Authors: Muller N.J. Published year: 2003 |
Marion Levine teaches English, Literature and Film Production at Los Angeles Center for Enriched Studies, Los Angeles, CA Measure for Measure, Act 4 or 5 What's On for Today and Why Students will choose a character from Measure for Measure and create a "back story" for that character. This will encourage students to read the text closely looking for clues regarding a specific character's |
history. Students will re-read a portion of the text and then write about what has happened to the character before the play begins. They will then create an artifact, such as a diary or journal entry, written by the charcacter they have selected. This will allow them the opportunity to think like the character and to view the events of the play from a |
specific point of view. This lesson will take two 40 minute class periods. What You Need Measure for Measure, Folger Edition What To Do 1. Explain the concept of a "back story" as the important events that occur to a character before the play begins. You may need to prompt students with questions such as: What was the character like as a child? In |
what situation did he/she grow up? Students will need to show how the script supports their choices. 2. Have the students write a one or two page back story in either the first or third person. 3. Divide students into small groups of 4 or 5 and have them re-read Act 4 or Act 5, combing throught the text for character details. 4. Have |
students write a letter, diary or journal entry from their selected characters point of view (first person). This artifact should concern one or more characters in the play. 5. For increased authenticity, appropriate for an "Extra-Extended" book, students could write their letter, diary entry using calligraphy, a handwriting font or on a piece of yellowed paper. 6. Allow students time to read their pieces |
and share their artifacts with the class. How Did It Go? Were students able to justify their choices with reference to the text? Did their artifacts accurately portray character traits that can be interpreted from the text? Were students able to convey a sense of the character's perspective through this activity? This lesson could be applied to any fictional text that the students read |
in class. Through close reading and attention to a specific character, students are able to identify with, and understand the concerns of a character on a deeper level. Possible choices could include Jay Gatsby, Hester Prynne,and Atticus Finch. If you used this lesson, we would like to hear how it went and about any adaptations you made to suit the needs of YOUR students. |
Vanilla is a product of Lussumo:Documentation and Support. 1 to 16 of 16 This year’s Nobel Prize in medicine went to a trio of scientists who discovered the enzyme telomerase, which allows cells to divide without any limits, making them effectively immortal.It may be nature’s greatest double-edged sword. Coax cells |
into producing telomerase, and they will survive indefinitely, but they will also become cancerous. “In the absence of a comprehensive understanding, it’s very dangerous,” Muller said. “We have to figure out how to do maintenance on our telomeres.”Muller thinks humans could live for 90 to 210 years once scientists know |
more about the molecular basis of aging.“If we could figure out how to do maintenance, we could extend our lives,” he said. “But it has to be done very carefully, and we’d have to have a comprehensive understanding of the mechanism. ” It really does my heart good to know |
Cancer Fighting Foods/Spices The National Cancer Institute estimates that roughly one-third of all cancer deaths may be diet related. What you eat can hurt you, but it can also help you. Many of the common foods found in grocery stores or organic markets contain cancer-fighting properties, from the antioxidants that neutralize the damage caused by free radicals to the powerful phytochemicals that scientists are |
just beginning to explore. There isn’t a single element in a particular food that does all the work: The best thing to do is eat a variety of foods. The following foods have the ability to help stave off cancer and some can even help inhibit cancer cell growth or reduce tumor size. Avocados are rich in glutathione, a powerful antioxidant that attacks free |
radicals in the body by blocking intestinal absorption of certain fats. They also supply even more potassium than bananas and are a strong source of beta-carotene. Scientists also believe that avocados may also be useful in treating viral hepatitis (a cause of liver cancer), as well as other sources of liver damage. Broccoli, cabbage, and cauliflower have a chemical component called indole-3-carbinol that can |
combat breast cancer by converting a cancer-promoting estrogen into a more protective variety. Broccoli, especially sprouts, also have the phytochemical sulforaphane, a product of glucoraphanin – believed to aid in preventing some types of cancer, like colon and rectal cancer. Sulforaphane induces the production of certain enzymes that can deactivate free radicals and carcinogens. The enzymes have been shown to inhibit the growth of |
tumors in laboratory animals. However, be aware that the Agriculture Department studied 71 types of broccoli plants and found a 30-fold difference in the amounts of glucoraphanin. It appears that the more bitter the broccoli is, the more glucoraphanin it has. Broccoli sprouts have been developed under the trade name BroccoSprouts that have a consistent level of sulforaphane – as much as 20 times |
higher than the levels found in mature heads of broccoli. Carrots contain a lot of beta carotene, which may help reduce a wide range of cancers including lung, mouth, throat, stomach, intestine, bladder, prostate and breast. Some research indicated beta carotene may actually cause cancer, but this has not proven that eating carrots, unless in very large quantities – 2 to 3 kilos a |
day, can cause cancer. In fact, a substance called falcarinol that is found in carrots has been found to reduce the risk of cancer, according to researchers at Danish Institute of Agricultural Sciences (DIAS). Kirsten Brandt, head of the research department, explained that isolated cancer cells grow more slowly when exposed to falcarinol. This substance is a polyacethylen, however, so it is important not |
to cook the carrots. Chili peppers and jalapenos contain a chemical, capsaicin, which may neutralize certain cancer-causing substances (nitrosamines) and may help prevent cancers such as stomach cancer. November 20, 2008 at 3:27 pm Maybe you should be eating more beets, left, or chopped cabbage. (Credit: Evan Sung for The New York Times, left Nutritionist and author Jonny Bowden has created several lists of |
- Beets: Think of beets as red spinach, Dr. Bowden said, because they are a rich source of folate as well as natural red pigments that may be cancer fighters. How to eat: Fresh, raw and grated to make a salad. Heating decreases the antioxidant power. - Cabbage: Loaded with nutrients like sulforaphane, a chemical said to boost cancer-fighting enzymes. How to eat: Asian-style |
slaw or as a crunchy topping on burgers and sandwiches. - Swiss chard: A leafy green vegetable packed with carotenoids that protect aging eyes. How to eat it: Chop and saute in olive oil. - Cinnamon: Helps control blood sugar and cholesterol. How to eat it: Sprinkle on coffee or oatmeal. - Pomegranate juice: Appears to lower blood pressure and loaded with antioxidants. How |
to eat: Just drink it. - Dried plums: Okay, so they are really prunes, but packed with cancer-fighting antioxidants. How to eat: Wrapped in prosciutto and baked. - Pumpkin seeds: The most nutritious part of the pumpkin and packed with magnesium; high levels of the mineral are associated with lower risk for early death. How to eat: Roasted as a snack, or sprinkled on |
salad. - Sardines: Dr. Bowden calls them “health food in a can.’’ They are high in omega-3’s, contain virtually no mercury and are loaded with calcium. They also contain iron, magnesium, phosphorus, potassium, zinc, copper and manganese as well as a full complement of B vitamins. How to eat: Choose sardines packed in olive or sardine oil. Eat plain, mixed with salad, on toast, |
or mashed with dijon mustard and onions as a spread. - Turmeric: The “superstar of spices,’’ it has anti-inflammatory and anti-cancer properties. How to eat: Mix with scrambled eggs or in any vegetable dish. - Frozen blueberries: Even though freezing can degrade some of the nutrients in fruits and vegetables, frozen blueberries are available year-round and don’t spoil; associated with better memory in animal |
studies. How to eat: Blended with yogurt or chocolate soy milk and sprinkled with crushed almonds. - Canned pumpkin: A low-calorie vegetable that is high in fiber and immune-stimulating vitamin A; fills you up on very few calories. How to eat: Mix with a little butter, cinnamon and nutmeg. You can find more details and recipes on the Men’s Health Web site, which published |
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