cssi/SciSciGPT-SciSciNet huggingface dataset:
A Computer-Aided Study of Confusion in Latin Morphology

The teaching of elementary Latin suffers from the same bane afflicting all language study: attrition is too high. This is generally acknowledged and widely lamented, but efforts to correct the situation have enjoyed very little success. There is good reason for this failure. We simply do not know enough about which areas of the subject are hardest for students to master, so we are unable to restructure syllabi to provide more balanced treatment; nor do we know which learning strategies tend to be most effective for the majority of students, so we are unable to offer sound advice to floundering scholars. The result is that each teacher is left to his or her own devices. The “good” teacher—bless his name—enjoys a high success rate but cannot share his success because it grows more out of instinctive behavior than out of cold choice. The “poor” teacher is doomed to a cycle of high drop rates, frustrated students, and fruitless self-examination. He is helpless and, it seems, unhelpable.
Effective principal component analysis

Principal Component Analysis (PCA) is one of the most widely used algorithmic techniques. When is PCA provably effective? What are its main limitations and how can we get around them? In this note, we discuss three specific challenges.
Teens and Social Media: A Case Study of High School Students' Informal Learning Practices and Trajectories

This study is a segment of a larger investigation of high school students' use of social media platforms and networks. In the spring of 2017, the researchers conducted detailed, individual interviews with high school students (10th and 12th grade) about their social media platforms and networks. During interviews inquiring about their social media practices more generally, many students shared examples of their informal learning practices on social media. Across these informal learning practices, three themes emerged: career/future planning, entrepreneurship, and hobbies.
Better Feature Matching for Placental Panorama Construction

Twin-to-twin transfusion syndrome is a potentially fatal placental vascular disease of twin pregnancies. The only definitive treatment is surgical cauterization of problematic vascular formations with a fetal endoscope. This surgery is made difficult by the poor visibility conditions of the intrauterine environment and the limited field of view of the endoscope. There have been efforts to address the limited field of view of fetal endoscopes with algorithms that use visual correspondences between successive fetoscopic video frames to stitch those frames together into a composite map of the placental surface. The existing work, however, has been evaluated primarily on ex vivo images of placentas, which tend to have more visual features and fewer visual distractors than the in vivo images that would be encountered in actual surgical procedures. This work shows that guiding feature matching with deep learned segmentations of placental vessels and grid-based motion statistics can make feature-based registration tractable even in in vivo images that have few distinctive visual features.
High incidence of advanced stage cancer and prolonged rectal bleeding history before diagnosis in young-onset patients with colorectal cancer.

3576Background: In contrast to the older population, the incidence of colorectal cancer (CRC) in younger patients (aged < 50 years) has been increasing in the last three decades. Younger patients t...
Enteral and parenteral nutrition considerations in pediatric patients.

Purpose Current clinical practice guidelines on management of enteral nutrition (EN) and parenteral nutrition (PN) in pediatric patients are reviewed. Summary The provision of EN and PN in pediatric patients poses many unique considerations and challenges. Although indications for use of EN and PN are similar in adult and pediatric populations, recommended EN and PN practices differ for pediatric versus adult patients in areas such as selection of EN and PN formulations, timing of EN and PN initiation, advancement of nutrition support, and EN and PN goals. Additionally, provision of EN and PN to pediatric patients poses unique compounding and medication administration challenges. This article provides a review of current EN and PN best practices and special nutrition considerations for neonates, infants, and other pediatric patients. Conclusion The provision of EN and PN to pediatric patients presents many unique challenges. It is important for pharmacists to keep current with pediatric- and neonatal-specific guidelines on nutritional management of various disease states, as well as strategies to address compounding and medication administration challenges, in order to optimize EN and PN outcomes.
Correlation between spinal cord diffusion tensor imaging and postural response latencies in persons with multiple sclerosis: A pilot study.

Abstract Purpose Longer latency of postural response in multiple sclerosis (MS) may be linked to imbalance and increased likelihood of falls. It may be caused by the compromised microstructural integrity in the spinal cord, as evidenced by slowed somatosensory conduction in the spinal cord. Thus, the purpose of this study is to investigate the correlation between latency of postural responses and microstructural integrity of the cervical spinal cord, the region particularly related to the disease severity in MS, using diffusion tensor imaging (DTI) metrics. Methods Seventeen persons with MS with mild-to-moderate disease severity were enrolled in this study. Postural response latencies of each patient were measured using electromyography of the tibialis anterior muscle (TA) and gastrocnemius muscle (GN) in response to surface perturbations. Cervical spinal cord DTI images were obtained from each patient. DTI mean, radial, axial diffusivity, and fractional anisotropy (FA) were measured between segments C4 and C6. Correlations of DTI metrics with postural response latencies, expanded disability status scale (EDSS) scores, and 25-foot walk (T25FW) were assessed using the Spearman's rank correlation coefficient at α = 0.05. Results Lower FA was significantly correlated with longer latencies measured on right TA in response to forward postural perturbations (r = −0.51, p = .04). DTI metrics showed no significant correlations with EDSS scores (r = −0.06–0.09, p = .73–0.95) or T25FW (r = −0.1–0.14, p = .6–0.94). DTI metrics showed no significant differences between subjects with and without spinal cord lesions (p = .2–0.7). Conclusions Our results showed a significant correlation between lower FA in the cervical spinal cord and longer latencies measured on right TA in response to forward postural perturbations in persons with MS, suggesting that impaired cervical spinal cord microstructure assessed by DTI may be associated with the delayed postural responses.
Introducing Parallelism to First-Year CS Majors

We propose to strengthen the computer science (CS) curriculum by embedding parallel concepts in a required first-semester seminar taken by all incoming declared CS majors. We introduce students to parallel computing concepts through a series of unplugged activities so that students see parallel approaches as a natural form of solution to a task. We describe a pilot offering of the class and activities, with measurements and analysis of what students self-report and their performance on assessments.
Fruit Fly Alphabets

The routine operations associated with tephritid fruit fly programs are divorced from the workings of the underlying science on traps and lures, which has developed more haphazardly through the work of individual researchers. Additionally, all trapping outcomes are probabilistic, rendering data interpretation problematic. Mark-release-recapture studies have proven valuable in providing estimates of minimum detectable population sizes for invasive fruit fly species. Both intra- and interspecific variation in lure/trap responsiveness demand further investigation, as the notion that “one trap/bait combination fits all” is probably not maximally effective.
Pseudomonas aeruginosa antimicrobial susceptibility test (AST) results and pulmonary exacerbation treatment responses in cystic fibrosis

Abstract Background Antimicrobial susceptibility testing (AST) of bacterial isolates is a time- and resource-intensive procedure recommended by cystic fibrosis (CF) treatment guidelines for antimicrobial selection for pulmonary exacerbation (PEx) treatment. Methods We studied relationships between Pseudomonas aeruginosa (Pa) isolate AST results, antipseudomonal PEx treatments, and treatment responses as change in weight and percent predicted forced expiratory volume in 1 s (ppFEV1) as well as future antimicrobial treatment hazard for PEx occurring at a CF care center from 1999 through 2018. Treatments were categorized by “Pa coverage” as complete (all Pa isolates susceptible by AST to at least one administered agent), none (no isolates susceptible), incomplete (some, but not all isolates susceptible), and indeterminant (administered antipseudomonals not evaluated by AST). Weight and ppFEV1 responses were compared across Pa coverage categories using unadjusted and adjusted general estimating equations; hazard of future treatment was assessed by Cox and logistic regression. Results Among 3820 antimicrobial PEx treatment events in 413 patients with Pa, 62.6% (2390) had complete Pa coverage; 8.9% (340), 2.4% (99), and 26.2% (1000), had no, incomplete, and indeterminant Pa coverage, respectively. Mean baseline to follow-up weight change was +0.74 kg [95% CI 0.63, 0.86]; ppFEV1 change was +1.60 [1.29, 1.90]. Pa coverage category was not associated with significant differences in weight or ppFEV1 change or with future antimicrobial treatment hazard. Conclusions We did not observe superior responses for AST-defined complete Pa coverage treatments versus lesser coverage treatments, suggesting that AST may be of little utility in choosing antimicrobials for CF PEx treatment.
European Commission’s Notice on the Definition of Relevant Market for the Purposes of Community Competition Law, Comment of the Global Antitrust Institute, Antonin Scalia Law School, George Mason University

This comment is submitted by the Global Antitrust Institute (GAI) to the European Commission (Commission) for consideration in relation to its consultation on its Notice on the definition of relevant market for the purposes of community competition law.
Nature, Nurture, and Financial Decision-Making

The goal of this application is to fund a research agenda in economics that examines the importance of "nature" (genes) and "nurture" (the environment), and their interactions, as drivers of individuals' behavior in the financial domain. The goal of this agenda is to advance our understanding of the fundamental factors that determine the most important financial decisions that people make during their lives, e.g., how much to save for retirement, how to invest and allocate savings to different assets and investment vehicles, and how much personal debt to accept. Many industrialized countries are moving away from defined benefit retirement plans and pay-as-you-go systems like Social Security, meaning that people will be responsible for their own savings. As we move towards more autonomy in the domain of savings and investments it becomes increasingly important for economists and policy makers to understand what determines people's financial decisions and also why people exhibit a long list of investment biases. Is this because of genetic predispositions, or because of social learning (e.g., from parents)? Does the environment moderate innate predispositions to certain financial decisions? The extent to which specific environments and market incentives eradicate or exacerbate genetic predispositions will also be examined. There are at least two reasons why this research agenda is important and has potential for broad impact. First, economists who model or empirically examine individual investor behavior in financial markets should understand the fundamental factors that explain individual differences in behavior in these markets. In this respect, our research contributes to a rapidly expanding literature which analyzes the biological, neural, and genetic factors that influence individuals' financial decisions. Second, from a public policy perspective, it is important to understand the extent to which individuals' financial decisions are influenced by genetic predispositions rather than environmental factors. That is, our results have implications for an evaluation of the effectiveness -- and possibly limitations -- of public policy initiatives with respect to, e.g., financial literacy, retirement savings, income and wealth inequality.
The Market Loves a Layoff

This paper examines whether layoffs damage or create firm value. Using a large sample of firm-matched layoff events, I show that layoffs increase firm value with abnormal returns increasing in the days and months following layoff announcements. Using a synthetic controls methodology, I also show that layoffs also continue to result in higher returns in the years following the layoff event. Using changes in minimum wage laws as a natural experiment, I show that layoffs often target low-skill workers, suggesting that layoffs do not necessarily destroy knowledge capital.
Cooking Object's State Identification Without Using Pretrained Model.

Recently, Robotic Cooking has been a very promising field. To execute a recipe, a robot has to recognize different objects and their states. Contrary to object recognition, state identification has not been explored that much. But it is very important because different recipe might require different state of an object. Moreover, robotic grasping depends on the state. Pretrained model usually perform very well in this type of tests. Our challenge was to handle this problem without using any pretrained model. In this paper, we have proposed a CNN and trained it from scratch. The model is trained and tested on the dataset from cooking state recognition challenge. We have also evaluated the performance of our network from various perspective. Our model achieves 65.8% accuracy on the unseen test dataset.
Increased Hospitalization and Mortality from COVID-19 in Prostate Cancer Patients

Background: Cancer patients with COVID-19 have a poor disease course. Among tumor types, prostate cancer and COVID-19 share several risk factors, and the interaction of prostate cancer and COVID-19 is purported to have an adverse outcome. Methods: This was a single-institution retrospective study on 286,609 patients who underwent the COVID-19 test at Mount Sinai Hospital system from March 2020 to December 2020. Chi-square/Fisher’s exact tests were used to summarize baseline characteristics of categorical data, and Mann–Whitney U test was used for continuous variables. Univariable logistic regression analysis to compare the hospitalization and mortality rates and the strength of association was obtained by the odds ratio and confidence interval. Results: This study aimed to compare hospitalization and mortality rates between men with COVID-19 and prostate cancer and those who were COVID-19-positive with non-prostate genitourinary malignancy or any solid cancer, and with breast cancer patients. We also compared our studies to others that reported the incidence and severity of COVID-19 in prostate cancer patients. Our studies highlight that patients with prostate cancer had higher susceptibility to COVID-19-related pathogenesis, resulting in higher mortality and hospitalization rates. Hospitalization and mortality rates were higher in prostate cancer patients with COVID-19 when compared with COVID-19 patients with non-prostate genitourinary (GU) malignancies.
Karyotypes of Coralsnakes (Reptilia: Elapidae) from the Western Hemisphere, with Comments on Intraspecific Variation and Centric Fission of Chromosomes

Karyotypes are described for Micruroides euryxanthus from Arizona and Micrurus tener from Texas. These are compared with karyotypes of other elapids from around the world, which exhibit significant interspecific variation. The largest macrochromosome of M. euryxanthus, which is metacentric, is shared by only two other species of coralsnakes from the New World. This may be a shared ancestral chromosome homologous to the largest macrochromosome that occurs in most other snakes, including some of the Australian elapids. The karyotype of M. tener from Texas has a ZZ:ZW1W2 sex chromosome system, which differs from individuals of this species reported previously from Louisiana. Over the relatively young 35-million-year global history of the Elapidae, karyotypes appear to have varied more than those of most other snakes throughout a 140-million-year history.
Coagulopathy with midtrimester induced abortion: Association with hyperosmolar urea administration

Abstract Coagulation changes, usually subclinical, have been reported in association with the induction of midtrimester abortion by the administration of intra-amniotic hypertonic sodium chloride, hyperosmolar urea, hyperosmolar urea plus prostaglandin F 2α , and hyperosmolar ura or hypertonic glucose plus prostaglandin E 2 . In addition, clinically significant coagulopathy has been described in association with the administration of hypertonic sodium chloride. This study details a three-year experience involving 3,034 cases of midtrimester elective abortion and describes six cases of coagulopathy in association with the administration of hypertonic sodium chloride and two cases in association with the administration of hyperosmolar urea. The significance of these findings and etiologic considerations are discussed.
Observations of interplanetary Lyman-alpha with the Galileo Ultraviolet Spectrometer: Multiple scattering effects at solar maximum

The Galileo Ultravilet Spectrometer Experiment (UVS) obtained a partial celestial sphere map of interplanetary Lyman-alpha (IP L alpha) on 13-14 December 1990 during the first Earth encounter. The Galileo spacecraft was near the downwind axis of the local interstellar medium flow. These UVS measurements sampled the downwind, anti-sunward hemisphere. The data were modeled using a hot model of the interplanetary hydrogen density distribution with the goal of studying multiple scattering effects in the inner solar system. The derived ratio in the downwind direction of the observed brightness and a single scattering model brightness, both normalized to unity in the upwind direction, is 1.82 +/- 0.2. This brightness ratio requires a multiple scattering correction which is 36% larger than can be accounted for by theoretical calculations. The hot model may require: (1) a temperature perturbation of the interstellar wind velocity distribution or (2) an additional downstream source of interplanetary hydrogen. However, a more likely exlanation which affects the hot model is the latitude dependence of the radiation pressure. This dependence, based on the known solar L alpha flux latitude variation at solar maximum, causes a downwind brightness enhancement by preferential focusing of H-atoms with trajectory planes containing the solar poles. This result implies that radiation pressure near the solar poles is nearly independent of solar cycle and is insufficient to lead to a net repulsion of hydrogen atoms by the sun, as can occur near the ecliptic plane during the solar maximum. In addition, the UVS performed 13 observations of IP L alpha while in cruise between Venus and the Earth in 3 directions fixed in ecliptic coordinates.
Chapter 3 Modulation of Lung Epithelial Sodium Channel Function by Nitric Oxide

Abstract Alveolar epithelial cells of mammalian lungs actively transport sodium (Na+) and chloride (Cl−) ions and these processes are important in fluid homeostasis. Sodium ions enter the apical membranes of both type I and type II alveolar epithelial cells through sodium selective, cation and cyclic nucleotide gated ion channels and are extruded across the basolateral membrane by the ouabain-sensitive Na,K-ATPase. This vectorial transport of Na+ ions (and concomitant movement of Cl− ions to maintain electroneutrality) creates an oncotic force leading to the reabsorption of fluid across both normal and damaged lungs. Nitric oxide and reactive oxygen nitrogen intermediates (formed by the reactions of nitric oxide with partially reduced oxygen species), generated in close proximity of epithelial cell membranes by activated inflammatory cells, modulate the activity of sodium channels via signal transduction mechanisms (such as increasing PKG and PKC) or by post-translational oxidative modifications of sodium channel proteins and their chaperons. Channel activity (and vectorial sodium transport) may be either increased or decreased depending on levels of reactive intermediates and length of exposure. Better understanding of these interactions would offer considerable new insights into the mechanisms leading to pulmonary edema in a number of pathological conditions.
Abstract #4409: Changes of cellular phosphoproteome in pancreas cancer cells in response to transketolase inhibitor oxythiamine

AACR Annual Meeting-- Apr 18-22, 2009; Denver, CO In our newly developed method, we have demonstrated that metabolic labeling of protein with amino acids of low isotope enrichment (mSILAC) can be used to determine protein synthesis or turnover rate. In this communication, using this new method we demonstrated that transketolase inhibitor oxythiamine (OT) can interfere cellular proteomic profile at both translational and post-translational levels in MIA PaCa cancer cells. MIA PaCa cell as a model was cultured in media containing an algal 15N amino acid mixture at 50% enrichment. The cellular proteome expressed differentially in MIA cells in response to OT treatment has been analyzed by using two dimensional gel electrophoresis (2-DE) coupled with MALDI-TOF/TOF MS. Analysis of cell lysates was then subjected to the identification of 15 phosphoproteins and 5 non-phosphoproteins differentially expressed in OT treated MIA cancer cells as compared to that in control group. The identified proteins include antioxidant enzymes, chaperones, calcium-binding proteins, proteases, and signal transduction proteins. Among these proteins, the expression of Hsps 90/27, 60S acidic ribosomal protein P0, nucleophosmin, \#945;-enolase, peroxiredoxin 4, and nuclear autoantigenic sperm protein were significantly suppressed by OT treatment. Comparing the calculated turnover rates of the phophosproteins to that of non-phosphoproteins, we found thatthe average turnover rates for phosphoproteins (70%) are much higher than that for non-phospho proteins (50%) among 20 differentially expressed proteins. Among the phosphoproteins, the turnover rate for hsp27 with the highest turnover rate is 75%. Therefore, this protein was further validated using immunohistochemical stain, showing that the sensitivity and specificity for this protein is 90% (n=15). We also observed that OT treatment deactivated p38 and JNK cascades and caused cancer cell cycle arrest. The phosphoproteins differentially expressed in OT treated cells may be related to the changes of the cellular activity. Our findings from this study may provide a valuable surrogate biomarker or novel drug target that could be used for early diagnosis of the disease and evaluation of therapeutic effectiveness. Citation Information: In: Proc Am Assoc Cancer Res; 2009 Apr 18-22; Denver, CO. Philadelphia (PA): AACR; 2009. Abstract nr 4409.
Hepatitis C Virus: From Laboratory to Clinic

Hepatitis C infects 170 million people worldwide, and has been labelled the 'silent epidemic' as a result of its concealed attack on the liver. This multidisciplinary overview covers basic concepts related to the discovery of the virus, development of serological and nucleic acid tests to detect infection, the structure of the virus genome, generation of virus gene products, and proposed replication scheme. It then goes on to introduce the epidemiology, transmission, pathogenesis of infection, the development of hepatocellular carcinoma associated with chronic virus infection, and current strategies for treatment. The book then discusses advances in cell culture systems, animal models of infection, and emerging treatments and vaccine development. Through its coverage of basic science, clinical consequences, and methods of research, this integrated and accessible account will be of immense value to biomedical scientists and clinicians alike, and a useful introduction for all those studying the virus and its effects.
Demographic and socioeconomic factors predictive of compliance with American Thyroid Association guidelines for the treatment for advanced papillary thyroid carcinoma

Background The American Thyroid Association (ATA) publishes evidence-based guidelines for the treatment of papillary thyroid carcinoma (PTC). We sought to identify factors associated with receiving treatment compliant with the 2006 ATA guidelines for advanced-stage PTC. Methods The 2006 ATA guideline compliance was examined in patients with stage III and IV PTC extrapolated from Surveillance, Epidemiology, and End Results (SEER). Results Sixty percent of patients received ATA-compliant treatment. A stepwise increase in compliance occurred between 2006 and 2009 (p-value trend = .0003). Age 45 to 64 years versus ≥65 (odds ratio [OR] = 0.682; 95% confidence interval [CI] = 0.57–0.81; p < .0001) and higher income (p trend = .012) were associated with an increased likelihood of receiving ATA-compliant care. African Americans (OR = 0.56; 95% CI = 0.42–0.76; p = .0001) and single patients (OR = 0.81; 95% CI = 0.67–0.97; p = .02) were less likely to receive ATA-compliant care. Conclusion This study highlights specific populations at risk for receiving non–ATA-compliant care for PTC and underscores the need to further implement guideline-based practice. © 2014 Wiley Periodicals, Inc. Head Neck, 2014
Impurity segregation in LPE growth of silicon from CuAl solutions

Al segregation at the solid-liquid interface and Cu segregation at the free silicon surface were studied in liquid-phase epitaxy (LPE) of silicon thin layers from mixtures of Cu-Al-Si. Using the multi-component regular solution model and experimental results, we found that Si-Al and Si-Cu interactions in the liquid solution are repulsive, and Al-Cu interaction is attractive. As a result, Al doping in silicon epitaxial layers is controlled by both Cu and Al compositions in the growth solution to allow epitaxy at about 900°C, with a substantial amount of Al present in the liquid for substrate surface-oxide removal. On the other hand, Cu concentration in the grown layers is determined by both the solid-liquid interface segregation during growth and segregation at the silicon surface after growth. The surface segregation phenomenon can be used to getter Cu from the bulk of silicon layers so that its concentration is much lower than its solubility at the layer growth temperature and the reported 10 17 cm -3 degradation onset for solar-cell performance.
Repeated administration of 5-methoxy-N,N-dimethyltryptamine to male rats potentiates stimulation of prolactine secretino by serotonin agonists

Abstract Repeated administration of 5-methoxy-N,N-demethyltryptamine (5MeODMT, 5 mg/kg, a serotonin agonist, every 3 h for a total of 4 injections) potentiated its prolactin (PRL)-releasing effect and that of two other serotonin agonists, quipazine and N,N-dimethyltryptamine. This pretreatment schedule had no effect on PRL response to anti-dopaminergic drugs. The onset of enhanced PRL response to serotonin agonists was gradual and appears to be due to sensitization of the serotonergic mechanism involved in the regulation of PRL secretion. The possible mechanisms underlying this phenomenon are discussed.
Rigidity Modulus of Beta-Brass Single Crystals

The rigidity modulus of ten beta-brass single crystals has been measured as a function of crystal orientation and of temperature from 25\ifmmode^\circ\else\textdegree\fi{} to 500\ifmmode^\circ\else\textdegree\fi{}C by the method of the composite piezoelectric oscillator. The reciprocal of the rigidity modulus, $\frac{1}{{G}^{\ensuremath{'}}}$, is linearly related to the orientation function. When these data are combined with Rinehart's previous measurements of Young's modulus, the principal elastic parameters are found to be 3.88, --- 1.52 and 0.578 \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}12}$ ${\mathrm{cm}}^{2}$/dyne, respectively, at room temperature. Curves and tables give them as functions of temperature up to and slightly beyond the critical temperature for order-disorder. At room temperature, the rigidity modulus is a maximum in the [100] direction, $G_{}^{\ensuremath{'}}{}_{[100]}{}^{}=17.3\ifmmode\times\else\texttimes\fi{}{10}^{11}$ dyne/${\mathrm{cm}}^{2}$, and a minimum in the [111] direction, ${G}^{\ensuremath{'}}[111]=1.35\ifmmode\times\else\texttimes\fi{}{10}^{11}$ dyne/${\mathrm{cm}}^{2}$, and at the critical temperature, ${G}^{\ensuremath{'}}[100]=13.5\ifmmode\times\else\texttimes\fi{}{10}^{11}$ dyne/${\mathrm{cm}}^{2}$ and ${G}^{\ensuremath{'}}[111]=1.06\ifmmode\times\else\texttimes\fi{}{10}^{11}$ dyne/${\mathrm{cm}}^{2}$. The elastic anisotropy as given by $\frac{{G}^{\ensuremath{'}}[100]}{{G}^{\ensuremath{'}}[111]}$ is 12.8 at room temperature, decreases to 12.3 at 250\ifmmode^\circ\else\textdegree\fi{}C and has a value of 13.0 at the critical temperature. The bending-torsion effect was found to be large and in agreement with theory.
A simple and direct proof of a bound on the zeros of a polynomial

A simple proof is given for the bound on the zeros of a polynomial recently presented by Dabke (1983). In a slightly modified form this result was first established by Cauchy.
Modeling the Multiaxial Strength of H-451 Nuclear Grade Graphite

Abstract The core of a prismatic High Temperature Reactor (HTR) is constructed from an array of nuclear graphite components. Similarly, the core of a Pebble Bed HTR is confined by large graphite blocks which define the (annular) core geometry. In both HTR designs the large graphite components act as neutron moderator and reflector as well as providing mechanical support to the active core. During reactor operation the graphite components of the core are subjected to complex stress states. Consequently, core designers need a suitable theory of failure. Both deterministic (e.g., maximum principal stress theory) and probabilistic (e.g., Weibull failure theory) have been considered. To test candidate failure theories a multiaxial testing program was conducted at Oak Ridge National Laboratory on H-451 graphite. Large specimens (∼27 cm length) were subjected to combined axial stress (tension and compression) and internal pressure. A total of 59 specimens were tested at 9 stress ratios in the first and fourth stress quadrants. Here, we report the basis and performance of a microstructurally based graphite fracture model and multiaxial strength data for grade H-451 graphite, along with the application of the model to predict the failure envelope for H-451 graphite in the first and fourth multiaxial quadrants.
Shock response of 3D woven composites: An experimental investigation

Abstract A modified shock tube was used to determine the effect of shock wave loading on 3D woven composite panels. The shock wave, which produces a short duration steeply rising pressure pulse when impacting the panel, was used to load the panels. The out of plane deformation response was measured using a full field Digital Image Correlation (DIC) technique. The results allow for measurements of full field displacements and strains in the samples. Three distinct textile composite architectures, corresponding to different amounts of Z-fiber (fiber tows that bind the different textile layers together) were investigated. Two separate shock intensities were used. Matrix micro-cracking was observed to be the mechanism by which failure is initiated, and this micro-cracking was found to occur closest to the center of the panel where the outer-surface straining is highest. Fiber tow failure was absent in the shock strengths studied in the present work. The results suggest that the 6% Z-fiber architecture provided the largest panel stiffness and the least amount of damage. This result suggests that this may be the optimal architecture and density for orthogonally woven Z-fiber reinforced composites, however due to the complex nature of the problem the same architecture with a different tow (and fiber) volume fraction may yield different results.
Nasal and bronchial provocation challenges with Bayberry (Myrica cerifera) pollen extract

Southern bayberry, distributed throughout the southeastern United States, is the source of the fifth most common windborne tree pollen in Tampa, Fla. Fifteen percent of 400 consecutive subjects evaluated for allergic respiratory symptoms in the Tampa Bay area had positive skin tests to bayberry pollen extract. Bayberry pollen extract was obtained commercially and used to perform 25 nasal and 22 bronchial challenges on 45 subjects. Twelve of 13 (92%) study subjects with allergic rhinitis and positive skin tests to bayberry pollen extract and two of 12 (17%) control subjects with negative skin tests had positive nasal challenges ( p =0.0001). Four of seven (57%) study subjects with extrinsic asthma and positive skin tests to bayberry pollen extract and none of the 15 (0%) control subjects with negative skin tests had positive bronchial challenges ( p =0.001). Sera from 30 subjects who underwent 31 challenges were assayed for bayberry pollen extract-specific IgE by plate radioimmunoassay. Specific, IgE antibodies were present in the sera of 8 of 13 (62%) subjects with positive challenges and absent in 15 of 18 (83%) subjects with negative challenges ( p =0.01). Intradermal skin tests with bayberry pollen extract were more predictive of provocation challenge results than plate radioimmunoassay (positive predictive value of 80%, 95% CI 62% to 98%; versus 73%, 95% CI 47% to 99%). Bayberry pollen extract is allergenic, and the Southern bayberry tree fulfills Thommen's criteria defining aeroallergen-producing plants.
The Circuit-Field Connection in Two-Dimensional AC Finite-Element Analysis of Multiply-Excited Magnetic Structures

Based on the assumptions of quasistatic behavior, linear system properties, and two- dimensional configurations, a multiport circuit representation of multiply-excited magnetic systems is derived by utilizing the finite-element method of solution. This circuit model is used to simulate a variety of terminal constraints such as short- or open- circuited ports, series or parallel connections of conductors, and other specific terminations which can then be incorporated into the finite-element field calculations. This combined circuit-field approach is applied to a simple generic two-conductor magnetic system configuration illustrating, in particular, how high- frequency eddy-current effects are accounted for in the evaluation of the equivalent circuit parameters.
Electrophysiologic studies of supraventricular tachycardia in children. II. Prediction of specific mechanism by noninvasive features

Abstract The major indication for electrophysiologic study (EPS) in children with supraventricular tachycardia (SVT) is to determine the mechanism, so that specific medical or surgical treatment can be instituted. If it were possible to predict the mechanism of SVT by noninvasive means, then EPS would be unnecessary in certain cases. We therefore examined the following parameters in 103 children less than 18 years of age who underwent EPS for SVT: age of onset of SVT; predisposing factors; family history; and from the ECG in SVT, heart rate, P wave morphology, and presence of atrioventricular (AV) block. The mechanism was determined by standard EPS techniques at cardiac catheterization. The three most predictive parameters were predisposing factors, age at onset of SVT, and P wave morphology. Frequency distributions of each of these parameters were calculated for each type of SVT. For example, in patients with a normal heart, the most common types of SVT were Wolff-Parkinson-White syndrome (WPW), unidirectional retrograde accessory pathway (URAP) and AV node reentry. Junctional ectopic tachycardia did not occur in patients with normal hearts. In patients with age of onset of SVT under 4 months, WPW and URAP were most common; sinus node reentry and atrial muscle reentry did not occur in this age group. Using frequency distribution data, we then considered the 103 patients as unknowns and attempted to predict mechanism. We were able to narrow the possibilities to three mechanisms for each patient. In 93 of 103 (90%) patients, one of the three mechanisms was correct. With inclusion of the response to cardioversion (ectopic foci unaffected) and examination of the postcardioversion ECG (for WPW and Lown-Ganong-Levine syndromes), accuracy was improved; 59 had single diagnosis (54 patients correct) and the other 44 were narrowed to two diagnoses (one of the two correct in all). We conclude that, in children, noninvasive prediction of the mechanism of SVT is successful in narrowing the diagnostic possibilities. If a surgically curable diagnosis (WPW, concealed WPW, atrial ectopic focus tachycardia, junctional ectopic focus tachycardia) is likely, and if the patient has had frequent recurrences of SVT for longer than 1 year and requires drugs in addition to digoxin for treatment, we recommend EPS for confirmation of the mechanism and localization of SVT.
Multiple-organ effect of normobaric hyperoxia in neonatal rats.

Purpose Prolonged exposure to normobaric hyperoxia (NH) is associated with blood leukocyte activation and sequestration in the lung. Whether NH-induced leukocyte activation and sequestration can affect extrapulmonary organs or blood cellular profile has not been systematically investigated. We studied simultaneous changes in blood cellular profile and pulmonary, renal, and intestinal histology during NH and after return to air breathing (“weaning”). Materials and Methods One-day-old rats were exposed to 2 to 4 days of NH (Fio2 >0.98) or normoxia (Fio2 = 0.21), with or without weaning. Pups were then euthanized and 100 μL of blood was collected (cardiac puncture) for differential white blood cells analysis (n = 12 per group). The lungs, a piece of distal ileum, and the left kidney were removed for histologic evaluation. Results Both NH and weaning generated significant increases in blood neutrophil count, whereas lymphocyte population was significantly increased only after weaning (P < .05; analysis of variance with Bonferroni correction for multiple comparisons). Normobaric hyperoxia created mild increases in the renal tubular necrosis, dilation, regeneration, and interstitial inflammation. A significant increase in the intestinal serosal and submucosal vasodialation and vascularization occurred 1 day after weaning from 4 days of NH (P < .001). These extrapulmonary events coincided with the development of histologic manifestations of pulmonary oxygen toxicity. Conclusions Development of pulmonary oxygen toxicity in neonatal rats is associated with significant changes in differential leukocyte counts and histologic alterations in the kidney and ileum. We speculate that activation of circulating leukocytes and/or direct effect of NH may affect certain peripheral organs independently from the NH-induced pulmonary pathology.
Spontaneous bilateral ankle and midfoot sepsis in a nonimmunocompromised patient.

We describe a 70-year-old nonimmunocompromised woman with spontaneous bilateral ankle and midfoot sepsis and a deep-space abscess of the right lower leg. Salvage of both limbs was achieved by aggressive bilateral soft-tissue and osseous debridement, including a four-compartment fasciotomy of the right lower leg, antibiotic-loaded polymethyl methacrylate bone cement implantation, delayed allogeneic bone grafting of the osseous defects impregnated with autologous platelet-rich plasma bilaterally, and external fixation immobilization, implantable bone growth stimulation, and split-thickness skin graft coverage of the right lower leg, ankle, and foot. Osseous incorporation of the bone grafts bilaterally occurred 8 weeks after surgery. No soft-tissue or osseous complications occurred during the postoperative period or at 18-month follow-up except for arthrofibrosis in the right ankle; there was no evidence of recurrent abscesses, sequestrum, or wound-related problems. A review of the literature regarding bilat...
Myopic picosecond laser keratomileusis with the neodymium-yttrium lithium fluoride laser in the cat cornea.

Objective: The study aimed to evaluate the effects of myopic picosecond laser keratomileusis (PLK) in the feline model with follow-up of up to 6 months. Design: The study design was a case-controlled, feline animal model. Participants: The procedure was completed in 1 eye each of 12 cats divided into 3 groups (group 1, sham operation; group 2, 100- μ m lenticle thickness; and group 3, 150- μ m lenticle thickness). The second eye of each cat was used as a control. Intervention: Picosecond laser keratomileusis, a new intrastromal laser technique with the neodymium-yttrium lithium fluoride picosecond laser, was presented. The procedure, analogous to laser keratomileusis in situ, consists of two lamellar ring cuts and one vertical ring-shape cut that define a 4-mm—diameter intrastromal lenticle. Main Outcome Measures: Corneal pachymetry, topography, tonometry, and biomicroscopic examination were performed before and after surgery at scheduled intervals for 6 months. Results: The mean (±standard deviation) diopter change for group 2 was 5.4 ± 3.2 diopters at 1 month and remained stable during the 6-month period. For group 3, the change was 8.1 ± 0.22 diopters at 1 month and 6.8 ± 1.5 diopters at 6 months. Group 1 (sham operation) did not show significant diopter change compared with that of control eyes at any timepoint. Pachymetry results for group 1 showed no significant difference in the thickness of the cornea at any timepoint ( P >0.05). For groups 2 and 3, the corneal thickness was reduced significantly by 1 month ( P Conclusion: Myopic intrastromal PLK produces a refractive effect on the cornea that depends on the thickness of the lenticle removed and persists after 6 months with minimal stromal haze and no surgical complications. The authors' results, although encouraging, indicate the need for further studies to confirm the efficacy of PLK as a valid refractive procedure.
Biodiesel Combustion and Emissions in Engines Using Modern Common-Rail Fuel Injection Systems

This study performed experimental testing of a multi-cylinder diesel engine using different blends of biodiesel and diesel fuel. The engine used an electronically-controlled common-rail fuel injection system to achieve a high injection pressure. The operating parameters that were investigated included the injection pressure, injection timing, and exhaust gas recirculation rate. Results showed that biodiesel generally reduced soot emissions and increased NOx emissions. The increase in NOx emissions was not due to the injection timing shift when biodiesel was used because the present fuel injection system was able to give the same fuel injection timing. At high exhaust gas recirculation rates, emissions using regular diesel and 20% biodiesel blends are very similar while 100% biodiesel produces relatively different emission levels. Therefore, the increase in NOx emissions may not be a concern when 20% biodiesel blends are used with high exhaust gas recirculation rates in order to achieve low temperature combustion conditions.Copyright © 2008 by ASME
Avian Visual Behavior and the Organization of the Telencephalon

Birds have excellent visual abilities that are comparable or superior to those of primates, but how the bird brain solves complex visual problems is poorly understood. More specifically, we lack knowledge about how such superb abilities are used in nature and how the brain, especially the telencephalon, is organized to process visual information. Here we review the results of several studies that examine the organization of the avian telencephalon and the relevance of visual abilities to avian social and reproductive behavior. Video playback and photographic stimuli show that birds can detect and evaluate subtle differences in local facial features of potential mates in a fashion similar to that of primates. These techniques have also revealed that birds do not attend well to global configural changes in the face, suggesting a fundamental difference between birds and primates in face perception. The telencephalon plays a major role in the visual and visuo-cognitive abilities of birds and primates, and anatomical data suggest that these animals may share similar organizational characteristics in the visual telencephalon. As is true in the primate cerebral cortex, different visual features are processed separately in the avian telencephalon where separate channels are organized in the anterior-posterior axis roughly parallel to the major laminae. Furthermore, the efferent projections from the primary visual telencephalon form an extensive column-like continuum involving the dorsolateral pallium and the lateral basal ganglia. Such a column-like organization may exist not only for vision, but for other sensory modalities and even for a continuum that links sensory and limbic areas of the avian brain. Behavioral and neural studies must be integrated in order to understand how birds have developed their amazing visual systems through 150 million years of evolution.
Thermal degradation of piperazine polyamides I—Poly (terephthaloyl trans-2,5-dimethylpiperazine) and poly(oxalyl trans-2,5-dimethylpiperazine)

Abstract The thermal degradation of two heterocyclic polyamides, poly(terephthaloyl trans -2,5-dimethylpiperazine) and poly(oxalyl trans -2,5-dimethylpiperazine), is discussed in terms of rates, activation energies and degradation products. These piperazine polyamides are stable in a vacuum up to approximately 420°C, but beyond this temperature essentially total volatilization takes place. From the rates of degradation an activation energy of 64 kcal/mole was calculated for both polymers, but poly(oxalyl trans -2,5-dimethylpiperazine) volatilizes approximately two to three times faster than poly(terephthaloyl trans -2,5-dimethylpiperazine). The addition of trace amounts of sulphuric acid to poly(terephthaloyl trans -2,5-dimethylpiperazine) prior to its pyrolysis reduced the activation energy of degradation to 55 kcal/mole. Mass spectrometric analysis of the volatile degradation products indicates the appearance of large quantities of carbon monoxide and lesser amounts of water, carbon dioxide, hydrocarbons, hydrogen, pyrazines and pyrroles. The character of the rate curves, the nature of the volatile degradation products, and an activation energy of 64 kcal/mole point to a random thermal free radical degradation. In contrast to the behaviour of aliphatic polyamides, the amide linkages in both poly(terephthaloyl trans -2,5-dimethylpiperazine) and poly(oxalyl trans -2,5-dimethylpiperazine) are quite resistant to acid-catalysed hydrolytic breakdown at elevated temperatures.
Effect of total and rumen undegradable protein on the performance of cows fed low fiber diets.

Twelve multiparous and 18 primiparous Holstein cows were fed a 17.3% CP, 21.0% ADF diet during wk 2 through 6 postpartum. Cows then were assigned from wk 7 through 14 to one of three low fiber (10.7% ADF) dietary treatments containing either 14.4 or 18.7% CP, the latter with or without a soybean meal enhanced with rumen undegradable protein. Treatments had no effect on milk yield or composition in multiparous cows, although milk fat percentage was not depressed in multiparous cows receiving the low fiber diets. The soybean meal diet enhanced with mien undegradable protein increased yields of milk, 4% FCM, fat, protein, and DMI compared with the 14.4% CP diet in primiparous cows; it also increased yields of 4% FCM and fat versus the 18.7% CP, untreated diet in primiparous cows. Blood urea N concentrations were greater for high CP diets than for the low CP diet in both parity groups. Rumen acetate:propionate ratios were higher for both high CP diets than for the low CP diet in multiparous cows. Soybean meal enhanced with rumen undegradable protein improved yields of milk and its components in primiparous cows fed low fiber diets, even when high protein diets were fed.