gebhart/patrepeval huggingface dataset:
Design studies for a PET detector module using a PIN photodiode to measure depth of interaction (1994)

We present design studies of a multi-layer PET detector module that uses an 8/spl times/8 array of 3 mm square PIN photodiodes to both identify the crystal of interaction and measure the depth of interaction. Each photodiode is coupled to one end of a 3/spl times/3/spl times/30 mm BGO crystal, with the opposite ends of 64 such crystals attached to a single 1" square photomultiplier tube that provides a timing signal and energy discrimination. Each BGO crystal is coated with a lossy reflector, so the ratio of light detected in the photodiode and photomultiplier tube depends on the interaction depth in the crystal, and is used to determine this depth of interaction on an event by event basis, A test module with one 3/spl times/3/spl times/30 mm BGO crystal, one 3 mm square PIN photodiode, and one photomultiplier tube is operated at -20/spl deg/C with an amplifier peaking time of 4 /spl mu/s, and a depth of interaction resolution of 5 to 8 mm fwhm measured. Simulations predict that this virtually eliminates radial elongation in a 60 cm diameter BGO tomograph. The photodiode signal corresponding to 511 keV energy deposit varies linearly with excitation position, ranging from 1250 electrons (e/sup -/) at the end closest to the photodiode to 520 e/sup -/ at the opposite end. The electronic noise is a position independent 330 e/sup -/ fwhm, so the signal to noise ratio is sufficient to reliably identify the crystal of interaction in a 64 element module.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Secretion of melanin-concentrating hormone and neuropeptide-EI from cultured rat hypothalamic cells. (1992)

Rat melanin-concentrating hormone (MCH) is a homolog of the peptide first isolated from salmon pituitary glands which produces melanosome aggregation within melanophores of teleost fish as well as interacting with the hypothalamic-pituitary axis. We have previously characterized the rat and human MCH counterparts as identical 19-amino acid peptides showing approximately 70% peptide sequence identity to salmon MCH. Immunoreactivity for MCH has been found in high concentrations within cell bodies of the dorsolateral hypothalamus, with projections to the hippocampus, brainstem, posterior pituitary, and cerebral cortex. We have adapted a cultured cell model for studying MCH secretory responses of hypothalamic cells obtained from 7-day-old rats. MCH and the MCH precursor-derived peptide neuropeptide glutamic acid isoleucine (NEI) were secreted from these cells after 2 days of culture and for up to 22-24 days of culture. The secreted peptides were confirmed by HPLC analysis and RIA to be identical to MCH isolated from rat hypothalamic tissue and to the sequences of MCH and NEI predicted from the MCH precursor. MCH and NEI secretion was stimulated 3- to 5-fold by 8-bromo-cAMP and 8-bromo-cGMP. Dexamethasone produced a dose-dependent increase in cell content of both MCH and NEI and an increase in MCH secretion. The present study is the first to demonstrate the existence of the predicted peptide NEI in a biological system and indicates that cultured neonatal rat hypothalamic cells are a useful model for the study of MCH/NEI release in vitro.
Improving the efficiency of hierarchical structure-and-motion (2010)

We present a completely automated Structure and Motion pipeline capable of working with uncalibrated images with varying internal parameters and no ancillary information. The system is based on a novel hierarchical scheme which reduces the total complexity by one order of magnitude. We assess the quality of our approach analytically by comparing the recovered point clouds with laser scans, which serves as ground truth data.
Combined macro- and microrheometer for use with Langmuir monolayers (2008)

A Langmuir monolayer trough that is equipped for simultaneous microrheology and standard rheology measurements has been constructed. The central elements are the trough itself with a full range of optical tools accessing the air-water interface from below the trough and a portable knife-edge torsion pendulum that can access the interface from above. The ability to simultaneously measure the mechanical response of Langmuir monolayers on very different length scales is an important step for our understanding of the mechanical response of two-dimensional viscoelastic networks.
Experimental brain injury induces differential expression of tumor necrosis factor-α mRNA in the CNS (1996)

In the present study, we examined the expression of tumor necrosis factor-α (TNF-α) mRNA in specific regions regions following experimental lateral fluid percussion traumatic brain injury (TBI) in rats. Adult Sprague-Dawley rats (n = 42) were anesthetized with sodium pentobarbital (60 mg/kg, i.p.) and subjected to lateral fluid percussion brain injury of moderate severity (2.4 atm.) centered over the left temporoparietal cortex, or ‘sham’ treatment (anesthesia and surgery without injury). Animals were killed by decapitation at 1, 6 or 24 h post injury, brains removed, and tissue samples of left (injured) parietal cortex (LC), right parietal cortex (RC), left adjacent cortex (LA), right adjacent cortex (RA), left hippocampus (LH) and right hippocampus (RH) were prepared. Total RNA was isolated and Northern blot hybridization was performed. TNF-α mRNA is expressed as the percent relative radioactivity of macrophage (positive control) RNA. In sham or naive animals, no consistent changes in expression of TNF-α mRNA were observed in any of the six brain areas at any times (less than 5%). A marked increase of TNF-α mRNA expression was observed in LH (104 ± 17, P < 0.05 compared with sham), LC (105 ± 21, P < 0.05) and LA (69 ± 8, P < 0.01) in the traumatized hemisphere 1 h following injury. An increased TNF-α mRNA expression was also observed in LH (46 ± 8, P < 0.05), LC (30 ± 3, P < 0.01) and LA (32 ± 3, P < 0.01) at 6 h which resolved by 24 h following injury. In the contralateral hemisphere, expression of TNF-α mRNA was increased in RH (46 ± 2, P < 0.01) at 1 h and in RA (26 ± 6%, P < 0.05) at 6 h. These results indicate that following parasagittal fluid percussion brain injury, the temporal expression of TNF-α mRNA is altered in specific brain regions, including those of the non-traumatized hemisphere. Post-traumatic alteration in gene expression of TNF-α might play an important role in both the acute and regenerative response to CNS trauma.
Rate-distortion optimized color quantization for compound image compression (2007)

In this paper, we present a new image compression scheme, which is specially designed for computer generated compound color images. First we classify the image content into two kinds: text/graphic content and picture content. Then two different compression schemes are applied blocks of different types. We propose a two stage segmentation scheme which combines thresholding block features and rate-distortion optimization. The text/graphics blocks compression scheme consists of two parts: color quantization and lossless coding of quantized images. The input images will first be color quantized and converted to codebooks and labels, introducing constraint distortion to the color quantization images. Then generated labels and codebooks are lossless compressed respectively. We proposed a rate-distortion optimized color quantization algorithm for text/graphic content, which introduces distortion to text content and minimizes the bit rate produced by the following lossless entropy compression algorithm. The picture content is compressed using conventional image algorithms like JPEG. The results show that the proposed scheme achieves better coding performance than other images compression algorithms such as JPEG2000 and DjVu.
Fast assay of glucosamine in pharmaceuticals and nutraceuticals by capillary zone electrophoresis with contactless conductivity detection (2008)

A novel capillary electrophoresis (CE) method with contactless conductivity detection suitable for the determination of glucosamine (GlAm) and K(+) in pharmaceuticals was devised. Under the optimum conditions (aqueous 30 mM acetate buffer of pH 5.2 as the background electrolyte; voltage 30 kV; 25 degrees C), GlAm (migrating as glucosaminium cation) was well separated from K(+) that could occur in the dosage forms as excipient. The CE analysis was performed in fused-silica capillaries (50 microm i.d., 75 cm total length, 27 cm to detector) and the separation took <3 min. The calibration graphs were linear for both GlAm (100-300 microg/mL; r(2)=0.997) and K(+) (15-75 microg/mL; r(2)=0.997) when using ethanolamine (100 microg/mL) as the internal standard. The LOD values (S/N=3) were 9.3 microg/mL for GlAm and 2.9 microg/mL for K(+). The method was applied to the assay of GlAm content in various dosage forms. Intermediate precision evaluated by determining the content of GlAm in a single formulation on 3 consecutive days was characterized by RSD 2.35% (n=15). Acceptable accuracy of the CE method was confirmed by the added/found GlAm recovery experiments (recoveries 94.6-103.3%) and by statistical comparison of the results attained by the proposed CE and a reference HPLC method.
Motion-Compensation Techniques in Neonatal and Fetal MR Imaging (2012)

Fetal and neonatal MR imaging is increasingly used as a complementary diagnostic tool to sonography. MR imaging is an ideal technique for imaging fetuses and neonates because of the absence of ionizing radiation, the superior contrast of soft tissues compared with sonography, the availability of different contrast options, and the increased FOV. Motion in the normally mobile fetus and the unsettled, sleeping, or sedated neonate during a long acquisition will decrease image quality in the form of motion artifacts, hamper image interpretation, and often necessitate a repeat MR imaging to establish a diagnosis. This article reviews current techniques of motion compensation in fetal and neonatal MR imaging, including the following: 1) motion-prevention strategies (such as adequate patient preparation, patient coaching, and sedation, when required), 2) motion-artifacts minimization methods (such as fast imaging protocols, data undersampling, and motion-resistant sequences), and 3) motion-detection/correction schemes (such as navigators and self-navigated sequences, external motion-tracking devices, and postprocessing approaches) and their application in fetal and neonatal brain MR imaging. Additionally some background on the repertoire of motion of the fetal and neonatal patient and the resulting artifacts will be presented, as well as insights into future developments and emerging techniques of motion compensation.
ChemInform Abstract: Design and Understanding of Heterogeneous Alkene Metathesis Catalysts (2008)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Reactions and Kinetics of Unsaturated C<sub>2</sub> Hydrocarbon Radicals (2004)

Abstract For Abstract see ChemInform Abstract in Full Text.
Asynchronous active replication in three-tier distributed systems (2003)

The deployment of server replicas of a service across an asynchronous distributed system (e.g., Internet) is a real practical challenge. This target cannot be indeed achieved by classical software replication techniques (e.g., passive and active replication) as these techniques usually rely on group communication toolkits that require server replicas to run over a partially synchronous distributed system to solve the underlying agreement problem. This paper proposes a three-tier architecture for software replication that encapsulates the need of partial synchrony in a specific software component of a mid-tier to free replicas and clients from the need of underlying partial synchrony assumptions. Then we propose how to specialize the mid-tier in order to manage active replication of server replicas.
Random Walk Based Inverse Influence Research in Online Social Networks (2013)

In online social networks, social influence of a user reflects his or her reputation or importance in the whole network or to a personalized user. Social influence analysis can be used in many real applications, such as link prediction, friend recommendation and personalized searching. Personalized Page Rank, which ranks nodes according to the probabilities that a random walk starting from a personalized node stops at all nodes, is one of the most popular metrics for influence analysis. In this paper, we study the problem of inverse influence in online social networks. Different from Personalized Page Rank, the inverse influence for a personalized node ranks nodes according to the probabilities that all nodes stop at the personalized node in limited steps. We propose two computation models for inverse influence, i.e., the random walk based and the path based. Both of the models have high computation complexity, and cannot be used in large graphs, so we propose a Monte Carlo based approximation algorithm. Experiments from synthetic and real world datasets show that, our algorithm has equivalent or even better accuracy than related researches in link prediction, and thus can be used in friend recommendation in online social networks.
Antibacterial, Antiviral and Antifungal Activities of Lipids (2010)

Lipids exhibit antimicrobial properties and are capable of killing Gram-negative and Gram-positive bacteria, enveloped viruses, yeast, fungi and parasites. The antimicrobial effects of lipids have been studied for more than a century and although most of the early studies focussed on the bactericidal effects of soaps, simple lipids including fatty acids were also shown to kill microbes. Lipids have been found to kill many pathogens that infect mucosa and skin, where they are considered to be potent natural inhibitors of human pathogens. In this chapter the in vitro antimicrobial activities of fatty acids, fatty alcohols and monoglycerides are reviewed, with emphasis on comparison of the antimicrobial effect of fatty acids and their 1-monoglycerides on various groups of microbes. Furthermore, the mechanism behind the microbicidal effect of these lipids will be discussed, as well as their possible role in host defense.
Spectral imaging of single molecules (2000)

Using a setup based on fluorescence microscopy we study fluorescence spectra of single chromophores. Being point like emission sources single molecules can be focused to the entrance slit of a spectrometer. Even with narrow slit width the light passes the system with almost no loss. We show that, making full use of the emission properties of a single molecule, fluorescence spectra of many single molecules can be recorded simultaneously using (hyper-)spectral imaging. The vibrational frequencies of the single terrylene chromophores in naphthalene are the same within the accuracy of our experiments but the vibronic lines show pronounced differences in their relative intensities.
The analysis of learning records and learning effect in blended e-learning (2005)

Some teachers adopt a blended learning model that combines traditional classroom teaching and an c-learning system. In this model, a teacher may teach the first few sessions in a classroom. After the students have established a general idea of the course, they can then proceed to on-line learning and interaction. This study aimed to discover the relationship between learning records and the learning effect in a blended c-learning environment through multiple regression analysis. The learning records considered included the grades for online assignments, reading time, the total number of login times, and the total number of online discussions. The learning effect was defined as the total grade for two monthly exams and one final exam. To collect learning record data, an c-learning system was designed that integrates the data collection functionality of learning activities with a teaching material managing module so that the learning records of all the learners are recorded automatically. With this system, an experiment was conducted on a program design course in a local high school. The results differed from those obtained in a 'pure' c-learning setting, and the online homework performance was the only item that significantly accounted for the learning effect, which is a natural result of learning procedural knowledge.
“Sensitivity” and “Specificity” Reconsidered: The Meaning of These Terms in Analytical and Diagnostic Settings (1997)

Imprecise usage of the terms "sensitivity" and "specificity" produces confusion in the diagnostic use of sophisticated laboratory test results. "Analytical sensitivity" represents the smallest amount of substance in a sample that can accurately be measured by an assay. "Analytical specificity" refers to the ability of an assay to measure on particular organism or substance, rather than others, in a sample. An assay's analytical sensitivity and analytical specificity are distinct from that assay's clinical diagnostic sensitivity and diagnostic specificity. "Diagnostic sensitivity" is the percentage of persons who have a given disorder who are identified by the assay as positive for the disorder. High analytical sensitivity does not guarantee acceptable diagnostic sensitivity. "Diagnostic specificity" is the percentage of persons who do not have a given condition who are identified by the assay as negative for the condition. False-positive reactions occur because of sample contamination and diminish the diagnostic specificity of the assay. The terms "sensitivity" and "specificity" should be used with the requisite adjectives because the "diagnostic" and the "analytical" meanings of these terms are very different.
Quotes, Order Flow, and Price Discovery (1997)

ABSTRACT The goal of this article is to examine the impact of 1975 Congressional mandate to integrate the trading of NYSE‐listed stocks. The conclusions are: most of the time, the New York Stock Exchange (NYSE) quote matches or determines the best displayed quote, and the NYSE is the most frequent initiator of quote changes. Non‐NYSE markets attract a significant portion of their volume when they are posting inferior bids or offers, indicating they obtain order flow for other reasons, such as “payment for order flow.” Yet, when a non‐NYSE market does post a better bid or offer, it does attract additional order flow.
Case-control study of increased mammographic breast density response to hormone replacement therapy. (2002)

Previous studies have demonstrated an association between current hormone replacement therapy (HRT) use and increased mammographic breast density. Many of these studies have also shown that only 20-35% of women initiating HRT respond in this manner. This subgroup of HRT responders may be at an increased risk of breast cancer. We performed a case-control study to investigate how women who experience increased density in response to HRT (cases) differ from women who do not experience an increase in density with HRT use (controls) with regard to breast cancer risk factors, type of HRT, weight change, and baseline breast density. Participants were female residents of Olmsted County, Minnesota who received routine screening mammograms at the Mayo Clinic. Cases included 172 women identified between the years 1998 and 1999 by Mayo radiologists as having a HRT response. Controls were women who did not experience an increase in mammographic density with HRT use and were matched to cases on age (+/-3 years), menopausal status, duration of HRT, month of initiation of HRT, and months between baseline and follow-up mammograms. Mammograms were obtained from cases and controls before and during HRT therapy. Breast density was read as a four-category Bi-Rads density grade measure and as a quantitative percentage estimate, using a computer-assisted method. Risk factor information was obtained from both chart review and a mammography database of patient-provided information. There was no association between HRT response and first-degree family history of breast cancer [odds ratio (OR), 0.8; 95% confidence interval (CI), 0.4-1.5], parity (OR, 0.8; 95% CI, 0.4-1.7), later age at first birth (OR, 0.8 for age >25 years versus nulliparous women; 95% CI, 0.4-1.8), or history of biopsy (OR, 0.9; 95% CI, 0.6-1.5). There was also no association with baseline weight or change in weight between a woman's baseline and follow-up mammograms. However, there was evidence of an association between HRT response and type of HRT used; women who experienced a mammographic increase in density with HRT had 2.3 greater odds (95% CI, 1.4-3.7) of having taken estrogen-progestin combined therapy than estrogen alone, compared with controls. This association was stronger among women with a baseline weight below the median (OR, 5.2; 95% CI, 1.6-17.6). Also, there was an inverse association between HRT response and baseline density. Because all risk factors examined accounted for only 26% of the variation in the HRT response, genes or other unmeasured factors are thought to be involved.
Multisensor surveillance systems based on image and video data (2003)

In this paper, a brief state of the art in the field of advanced surveillance systems is given. The goal is to provide a framework under which to describe the different contributions to research presented in the special session on multisensor surveillance systems based on image and video data. Some problems of interest considered by current research are highlighted starting from the necessity of augmented perceptual capabilities, to the use of video object based coding techniques, going to the capability of extending current video representation techniques in order to make it possible to easily correlate, recognize, index and retrieve multisensor video observations.
Advances, Interactions, and Future Developments in the CNS, Phenix, and Rosetta Structural Biology Software Systems (2013)

Advances in our understanding of macromolecular structure come from experimental methods, such as X-ray crystallography, and also computational analysis of the growing number of atomic models obtained from such experiments. The later analyses have made it possible to develop powerful tools for structure prediction and optimization in the absence of experimental data. In recent years, a synergy between these computational methods for crystallographic structure determination and structure prediction and optimization has begun to be exploited. We review some of the advances in the algorithms used for crystallographic structure determination in the Phenix and Crystallography & NMR System software packages and describe how methods from ab initio structure prediction and refinement in Rosetta have been applied to challenging crystallographic problems. The prospects for future improvement of these methods are discussed.