cssi/SciSciGPT-SciSciNet huggingface dataset:
“Bedside Anatomy”: A Tool to Contextualize Learning and Introduce Surgical Careers

Abstract Background Many medical students cite an unwelcoming culture in surgery and perceive surgeons as arrogant or unfriendly. These perceptions have been reported as factors discouraging medical students from applying to surgical residency programs. This highlights an opportunity early in medical education to address these negative stereotypes and create opportunities for positive interactions with surgeons. We hypothesize that positive experiences with surgical residents and introduction to representative surgical cases early in the medical school curriculum can provide a real-world context for learning anatomy and encourage students to consider a surgical career. Methods We developed and implemented a series of structured, one-hour, cadaver-based sessions cofacilitated by anatomists and surgical residents for medical students during their anatomy didactics. Sessions included common surgical cases and focused on critical thinking and problem-solving skills, while offering opportunities to review cadaver anatomy. Students completed a postcourse survey. Results Nine sessions were implemented with involvement of eight surgical residents and 185 students; 83 students completed a postcourse survey (response rate of 45%). A majority of students rated the sessions “very helpful” in terms of highlighting the importance of anatomy in medical education (n = 52, 63%) and providing clinical context (n = 59, 71%). 54% (n = 45) indicated interest in a surgical career and 64% (n = 53) agreed that session participation had increased their interest in surgery. Conclusions Overall, students agreed that sessions provided clinical context for their learning and increased interest in a surgical career. Surgical faculty and residents should engage in preclinical medical education to bridge the basic science and clinical years and introduce positive surgical role models early during medical training.
Osseointegrated prostheses for the rehabilitation of amputees (OPRA): results and clinical perspective

Introduction: Patients who undergo extremity amputation have historically used socket prosthetics to ambulate and perform daily functions; however, these prosthetics can be limited by poor terminal control and wear issues. In patients who have difficulty wearing their prostheses or with upper extremity amputations, osseointegrated implants may offer better function and quality of life. The Osseointegrated Prostheses for the Rehabilitation of Amputees (OPRA) was the first such device to become commercially available. Clinical trials have demonstrated benefit in patient gait, prosthetic use, and overall well-being, and new implants may be applied for various amputation levels.Areas covered: The OPRA, the most studied osseointegrated prosthetic stem, is reviewed, presenting indications, surgical procedure, complications, and results of clinical studies.Expert commentary: Osseointegration for amputees is an expanding field that has the potential to enhance rehabilitative potential. The OPRA implant is an effective device with a long life-span and low complication profile.
COMPARATIVE INCIDENCE AND COSTS ASSOCIATED WITH 30-DAY READMISSION FOR RECURRENT MI VERSUS MAJOR BLEEDING AMONG PATIENTS HOSPITALIZED WITH ACUTE MI IN THE UNITED STATES: A POPULATION-BASED COHORT STUDY

Readmission after acute myocardial infarction (MI) is frequent. Recurrent MI and major bleeding are common causes of readmission which pose a major economic burden on the healthcare costs. We queried the Healthcare Cost and Utilization Project Nationwide Readmissions Database for patients admitted
Converting natural nanoclay into modified nanoclay augments the toxic effect of natural nanoclay on aquatic invertebrates.

Abstract There is much interest in converting natural nanoclay into modified forms for a variety of applications. Aquatic organisms have been exposed to natural nanoclay throughout their entire evolutionary history, but concerns have been raised about the effects of modified nanoclay on aquatic organisms. We investigated the potential toxicity of a natural nanoclay (Na+ montmorillonite) and two modified nanoclays (Cloisite® 30B and NovaclayTM) on survivorship and body growth of Daphnia magna and Chironomus dilutus. Natural nanoclay had no harmful effect on C. dilutus but reduced the survival (~1mgL-1) and body growth (~100 mgL-1) of D. magna. NovaclayTM had no harmful effects on C. dilutus or the body growth of D. magna but an intermediate concentration (1 mgL-1) caused a stronger reduction in D. magna survival during chronic exposure than did natural nanoclay. Cloisite® 30B adversely affected D. magna survival at concentrations as low as 0.01 mgL-1 and nearly all D. magna died when exposed to concentrations of Cloisite® 30B that exceeded 10 mgL-1 during acute exposure and 1 mgL-1 during chronic exposure. Though Cloisite® 30B appeared to have no effect on the body growth of surviving D. magna, Cloisite® 30B reduced C. dilutus body growth (100 mgL-1). Cloisite® 30B likely has higher toxic effects due to the presence of quaternary ammonium compounds and/or particle stability. Our work demonstrates that natural nanoclay has harmful effects on aquatic animals and that the different ways of converting natural nanoclay into different types of modified nanoclays augments the toxic effect of nanoclay to differing degrees.
Factors associated with referral and completion of genetic counseling in women with epithelial ovarian cancer

Objective The National Comprehensive Cancer Network recommends that all women diagnosed with epithelial ovarian cancer undergo genetic testing, as the diagnosis of pathogenic variants may inform cancer survival and impact treatment options. The objective of this study was to assess factors associated with referral to genetic counseling in women with epithelial ovarian cancer. Methods A retrospective cohort study identified women with epithelial ovarian cancer from 2012 to 2017 at Massachusetts General Hospital and North Shore Medical Center, a community hospital affiliated with Massachusetts General Hospital. Multivariate logistic regression evaluated how race, age, stage, year of diagnosis, insurance status, family history of breast or ovarian cancer, and language relates to the receipt of genetic counseling. Results Of the total 276 women included, 73.9% were referred for genetic screening, of which 90.7% attended a genetic counseling visit. Older women were less likely to undergo genetic counseling (age ≥70 years: OR 0.26, 95% CI 0.07–0.94, p=0.04). Women who died within 365 days of initial oncology consult rarely reached a genetic counselor (OR 0.05, 95% CI 0.01–0.24, p Conclusion Older women with epithelial ovarian cancer and those who died within 1 year of initiation of care were less likely to undergo recommended genetic counseling. Race, insurance status, and language were not identified as predictive factors, although we were limited in this assessment by small sample size.
Sequential Folding of the Nickel/Cobalt Riboswitch Is Facilitated by a Conformational Intermediate: Insights from Single-Molecule Kinetics and Thermodynamics

The present work presents the first single-molecule fluorescence resonant energy transfer (smFRET) studies of the nickel/cobalt (NiCo) riboswitch, with temperature-dependent, single-molecule confocal microscopy to provide comprehensive kinetic and thermodynamic information on folding into a biochemically competent structure. The results indicate that the NiCo riboswitch first folds into a more compact "prefolded" conformation, with a preorganized binding pocket partially stabilized under physiological conditions by noncognate monovalent/divalent cations. Such a prefolded intermediate then has opportunity to fold further into a tightly ligand-bound structure, in response to the cognate ligands, Ni2+ or Co2+, with submicromolar affinities. Such stepwise ligand-induced folding represents a particularly clean example of a conformational selection ("fold-then-bind") mechanism, whereby a configuration dynamically accessible by thermal fluctuation is stabilized into the final folded state by ligand association. In addition, we observe a strong positive cooperativity in the ligand-induced folding kinetics with respect to both Ni2+ and Co2+ ligands. This provides maximal sensitivity in the riboswitch conformational response near [Ni2+] or [Co2+] ≈ Kd, which facilitates more accurate biochemical probing of the cell environment and therefore bioregulation of gene expression. Temperature-dependent kinetics at the single-molecule level has also been explored, which permits free energies to be deconstructed into enthalpic and entropic components along the folding coordinate. In the absence of the cognate ligand, a predominantly enthalpic barrier between the unfolded riboswitch (U) and the prefolded intermediate (I) suggests a rearrangement of the hydrogen bonding network, whereas in the presence of the cognate ligand, a large entropic penalty (-TΔS0 > 0) in forming the folded riboswitch conformation (F) is almost perfectly counterbalanced by an equivalent enthalpic gain (ΔH0 < 0) to yield ΔG0 ≈ 0. The thermodynamic results are therefore consistent with a simple physical picture of riboswitch folding, whereby association of the cognate ligand is strongly stabilized by Coulombic attraction while forming an entropically more ordered structure around the binding site.
After 62 years of regulating immunity, dexamethasone meets COVID-19.

Six months into the COVID-19 pandemic, effective treatments have been frustratingly sparse. The RECOVERY clinical trial, however, revealed that treatment with dexamethasone, a classic synthetic glucocorticoid, enhanced survival of critically ill patients with COVID-19. In this Comment, we discuss the immunological impacts of glucocorticoid therapy for COVID-19. The corticosteroid dexamethasome has been shown to reduce mortality in patients hospitalized with COVID-19 who require mechanical ventilation. Here, the authors describe how this immunosuppressive drug might work.
Extension of the Big Bang Theory

In this note we propose the extension of the Big Bang Theory of the origin of the Universe to the model that there are cycles of beginning and ending.
Series and Products in the Development of Mathematics

This is the second volume of a two-volume work that traces the development of series and products from 1380 to 2000 by presenting and explaining the interconnected concepts and results of hundreds of unsung as well as celebrated mathematicians. Some chapters deal with the work of primarily one mathematician on a pivotal topic, and other chapters chronicle the progress over time of a given topic. This updated second edition of Sources in the Development of Mathematics adds extensive context, detail, and primary source material, with many sections rewritten to more clearly reveal the significance of key developments and arguments. Volume 1, accessible even to advanced undergraduate students, discusses the development of the methods in series and products that do not employ complex analytic methods or sophisticated machinery. Volume 2 examines more recent results, including deBranges' resolution of Bieberbach's conjecture and Nevanlinna's theory of meromorphic functions.
Predicting drive for thinness and bulimic symptoms in female adults: might an act-frequency approach to the measurement of eating attitudes be useful?

The present study drew on the act-frequency approach to study eating disturbances by modifying the items of the Eating Expectancy Inventory (EEI) and Thinness and Restricting Expectancy Inventory (TREI) to their frequency versions, namely, EEI-F and TREI-F. In Study 1, a total of 354 young females completed the EEI-F and TREI-F for factor analysis. In Study 2, to assess for construct validity and predictive utility, an independent sample of 241 young females completed a test battery including the EEI-F, TREI-F, and measures of eating disturbances. In Study 1, results from an exploratory factor analysis indicated a one-factor solution for both EEI-F and TREI-F that account for 65.65% and 72.97% of the common variance, respectively. In Study 2, both measures were found to possess good test-retest reliability (11-week) in a subset sample of participants from Study 1. Moreover, in support for construct validity, we found both EEI-F and TREI-F scores were positively associated with scores on measures of eating disturbances (i.e., drive for thinness, bulimic symptoms). Finally, in support of utility, frequency of eating and thinness expectancies predicted eating disturbances above and beyond general attitudes associated with eating and thinness expectancies (measured by the EEI and TREI). Overall, the present findings provide promising evidence for the validity, reliability, and utility of the EEI-F and TREI-F as reliable, valid, and useful measures of frequency of eating and thinness expectancies in young females. Implications for the theory and clinical assessments were discussed.
Methodology for multi-objective optimization of wind turbine/battery/electrolyzer system for decentralized clean hydrogen production using an adapted power management strategy for low wind speed conditions

Abstract In this study, the utilization of renewable energy sources (RESs) like wind energy for clean hydrogen production via water electrolysis in small-scale decentralized plant is addressed. This paper proposes an approach for multi-objective optimization of wind-hydrogen production system (WHPS) while satisfying multiple technical constraints based on a dynamic power and hydrogen management strategy (PHMS). WHPS consists of wind turbines (WTs), water electrolyzer, battery bank, power converters and hydrogen tank. Multi-objective optimization consists of minimizing the total hydrogen deficit (THD), energy dump possibility (EDP), levelized cost of hydrogen (LCOH) as well as CO2 emission avoided (CO2EA) and natural gas preserved (NGP). Battery assistance for electrolyzer is enhanced through a dynamic PHMS adapted to low wind speed conditions. PHMS based multi-objective optimization algorithm is developed to find Pareto-optimal solutions. The optimization results reveal that the adequate design of PHMS plays a crucial role in minimizing THD, LCOH and EDP, while ignoring the EDP objective may reduce potentially LCOH. Under the selected base case conditions, small-scale hydrogen production via WHPS consisting of 250 kW alkaline-electrolyzer, 857.5 kW WTs, 719 kW h battery bank and 2022 kg hydrogen tank, for supplying hydrogen demand at full reliability (THD = 0%), results in LCOH of 33.70 $/kg, CO2EA of 87.75 ton/year, NGP of 28.96 ton/year and EDP of 9.96%.
Spontaneous Bile Leak in a Patient Without Recent Abdominal Surgery or Trauma.

Bile leaks are a rare occurrence most often seen as a complication of cholecystectomy. Other less common etiologies include endoscopic retrograde cholangiopancreatography (ERCP), percutaneous transhepatic cholangiography (PTC), liver surgery, percutaneous drainage of liver abscesses, living donor hepatectomy, and non-iatrogenic abdominal trauma. In this case study, we present a 67-year-old female with morbid obesity who presented with abdominal pain and was diagnosed with a spontaneous bile leak. She had no history of recent surgery or abdominal trauma. CT revealed that the patient's gallbladder was located in the right lower quadrant, most likely due to mass effect from a large ventral hernia, and possible fluid collection extending from the gallbladder along the surface of the anterior inferior right hepatic lobe. Hepatobiliary iminodiacetic acid (HIDA) was performed due to a concern for cholecystitis. HIDA demonstrated a bile leak in the right upper abdomen of unknown etiology. Initially, there was a concern for gallbladder obstruction. Gastroenterology recommended magnetic resonance cholangiopancreatography (MRCP), however, MRCP was not possible due to the patient's body habitus. The patient had normal liver function tests, was tolerating oral intake, and her abdominal pain resolved, therefore, we became less suspicious of gallbladder obstruction. This case suggests that bile leak should be included in the differential diagnosis for abdominal pain even in patients who have not had recent abdominal surgery or procedures. This case also highlights the unique anatomical finding of a right lower quadrant gallbladder secondary to mass effect from a large ventral hernia.
Healing Salves: Contingent Knowledge and Satisfying Surprises in Kiribati

Through the creative analytic practice of autoethnography and systematic sociological introspection, the author engages the subjectivity of narrative self in relation to a story involving treatment by an indigenous healer in the Republic of Kiribati. Through the lens of narratology, existential introspection, and ethics the author informs the moving vantage of the present through reflection on the micro personal and macro socio-cultural educational processes that bear influence on the narration and perception of a lived experience in hindsight. Through storying and reflecting through these lenses, this process problematizes the present story, but also yields degrees of greater awareness. This process of systematic sociological introspection is framed by Freeman’s (1997) notion of narrative integrity. That is, through reflection and reframing of the past, the author hopes to focus upon the possibilities of wider metacognitive perspective for both himself and the reader in the future.
SU-E-T-167: Characterization of In-House Plastic Scintillator Detectors Array for Radiation Therapy

Purpose: To characterize basic performance of plastic scintillator detectors (PSD) array designed for dosimetry of radiation therapy. Methods: An in-house PSD array has been developed by placing single point PSD into customized 2D holder. Each point PSD is a plastic scintillating fiber-based detector designed for highly accurate measurement of small radiotherapy fields used in patient plan verification and machine commissioning and QA procedures. A parallel fiber without PSD is used for Cerenkov separation by subtracting from PSD readings. Cerenkov separation was confirmed by optical spectroscopy. Alternative Cerenkov separation approaches are also investigated. The optical signal was converted to electronic signal with a photodiode and then subsequently amplified. We measured its dosimetry performance, including percentage depth dose and output factor, and compared with reference ion chamber measurements. The PSD array is then placed along the radiation beam for multiple point dose measurement, representing subsets of PDD measurements, or perpendicular to the beam for profile measurements. Results: The dosimetry results of PSD point measurements agree well with reference ion chamber measurements. For percentage depth dose, the maximal differences between PSD and ion chamber results are 3.5% and 2.7% for 6MV and 15MV beams, respectively. For the output factors, PSD measurements are within 3% from ion chamber results. PDD and profile measurement with PSD array are also performed. Conclusions: The current design of multichannel PSD array is feasible for the dosimetry measurement in radiation therapy. Dose distribution along or perpendicular to the beam path could be measured. It might as well be used as range verification in proton therapy.A PS hollow fiber detector will be investigated to eliminate the Cerenkov radiation effect so that all 32 channels can be used.
The molecules module of the brain architecture management system

We describe in this paper a new module of the brain architecture management system (BAMS; http://brancusi.usc.edu/bkms). The molecules module of BAMS makes this the first online knowledge management system that handles chemoarchitectonical data of brain regions in multiple species. This module allows insertion of complex reports of molecule presence as collated from the literature. The database structure of the module includes representation of molecule expression in different cell types as revealed by various techniques, coexpression data in different brain regions or cell types, and the physiological state of experimental animals. The module also allows insertion of time dependent experimental data. The Web interface of this module allows users to construct lists of brain regions where a molecule is present depending on the physiological state, retrieve further details about inserted records, and compare the time dependent data within or across experiments.
Observations from an American Conflict Resolution Professional in Serbia on the Effects of the Accessibility of International Media

In this Essay, I will address media coverage of four incidents that occurred while I was living and teaching in Belgrade, the capital of Serbia and Montenegro, 1 during 2003 to 2005: the March 2004 violence in Kosovo; a visit to Sarajevo, the capital of Bosnia and Herzegovina, in January 2005; the International Competition for Online Dispute Resolution (ICODR) during the winter of 2005; and a remembrance of the tenth anniversary of the Srebrenica Massacre in May 2005. It is the business of conflict resolution 2 professionals to look beyond the contours of the conflict situations in which they work. Filling in this background is done by asking many questions—questions about the context out of which the conflict arises, questions about the facts and the feelings that give form to the conflict, questions about where continuing the conflict in its present form will lead—and by listening carefully to the answers, both what is said and what remains unsaid. As a person without a personal stake in the outcome of the dispute, the conflict resolution professional helps those involved in a conflict examine the various aspects of the situation from outside themselves, perhaps from the shoes of the other, through the lens of history, or from the viewpoint of
Schmitt's Use and Abuse of Donoso Cortés on Dictatorship

‘The most drastic way to reject a proposition is not to dismiss it brusquely as disproven and merely brush it aside, but on the contrary to take it over and work it into an essential and grounded c...
A monitoring sensor management system for grid environments

Large distributed systems, such as computational grids, require a large amount of monitoring data be collected for a variety of tasks, such as fault detection, performance analysis, performance tuning, performance prediction and scheduling. Ensuring that all necessary monitoring is turned on and that the data is being collected can be a very tedious and error-prone task. We have developed an agent-based system to automate the execution of monitoring sensors and the collection of event data.
The Visualization of Second-Order Tensor Fields

The field of scientific visualization covers the study of visual representations of scientific data. This dissertation is the first extensive study of visualization techniques for second-order tensor fields defined across a n-dimensional space, $n\geq1$. We study the geometry and the topological structure of tensor fields, designing appropriate icons to represent the information. Tensor fields are multivariate; they can embed as much information as $n\sp2$ scalar fields, or equivalently, n vector fields. Visualizing continuous tensor data is, therefore, difficult mainly because the underlying continuity must be rendered while visual clutter has to be avoided. First, we design icons that decrease visual clutter by emphasizing the continuity of the tensor data. A n-dimensional, symmetric tensor field is equivalent to n orthogonal families of smooth and continuous curves that are tangent to the eigenvector fields. For $n=2$ we generate textures to render these trajectories, and for $n=3$ we use numerical integration. To fully represent the tensor data, we surround the resulting trajectories by tubular surfaces that represent the transverse eigenvectors--we call these surfaces hyperstreamlines. We also define the concept of a solenoidal tensor field, and we show that its hyperstreamlines possess geometric properties similar to the streamlines of solenoidal vector fields. Then, we analyze the topology of tensor fields. We derive a set of points and trajectories that represent the collective behavior of a continuous distribution of hyperstreamlines. We call these points degenerate points, because they occur where eigenvalues are equal to each other. Degenerate points can be of various types--trisectors, wedges, nodes, foci, saddles, dipoles, cusps, saddle-nodes, as well as other, more exotic patterns. We call the trajectories that underlie the topology of tensor fields separatrices. They are specific hyperstreamlines that are either limit cycles, or trajectories emanating from degenerate points and lying on the border of hyperbolic sectors. When a tensor field is defined across a surface, the topology of the surface limits the number and the nature of the degenerate points. We explore this relation, extending to tensor fields the Poincare-Hopf Theorem for vector fields.
Impact of material abundances distributions on detection power in hyperspectral images

Recently, we initiated research that attempts to describe performance of the subpixel target detectors using analytical formulas. We showed a surprising result that MFD always outperformed OSP in a traditional theoretical formulation of the detection problem. We also showed that this theoretical formulation was not realistic in practical target detection in real spectral images. The purpose of this paper is to give specific formulas for the detection power of MFD and OSP detectors under a more realistic scenario when the background signatures vary in both target and non-target pixel spectra. In this paper, we consider normal (Gaussian) distributions of the abundances of the background signatures. We show under what conditions the MFD outperforms OSP, and when the opposite is true. We show three numerical examples of the balance between the bias of MFD and the large variability of OSP and its impact on the relative performance of these detectors. realistic scenario when the background signatures vary in both target and non-target pixel spectra. More specifically, we consider normal (Gaussian) distributions of the abundances of the background signatures. At first, this assumption may not seem realistic, but the proper choice of the parameters of the normal distributions gives a reasonable approximation of the realistic values of the abundances. The advantage of the normal assumption is that we can obtain relatively simple formulas for detection power. Section II introduces the notation and gives the formulation of the model used in this paper. Section III provides the main results on the analytical formulas for the detection power of MFD and OSP detectors. Section IV considers a simplified scenario in order to obtain an interesting result, which shows when one of the two investigated detectors outperforms the other one. Section V shows three numerical examples of the balance between the bias of MFD and the large variability of OSP and its impact on the relative performance of these detectors.
Mechanism of Resistance to Antibiotic Synergism in Enterococci

Enterococci exhibit two types of resistance to streptomycin. Moderately high-level resistance is observed in most naturally occurring strains and can be overcome by simultaneous exposure to penicillin. In addition, very high-level resistance is found in those strains against which penicillin plus streptomycin fail to produce synergism in vitro. To study the mechanism of streptomycin resistance in enterococci, ribosomes from a wild-type strain and from a highly streptomycin-resistant mutant were isolated, characterized, and studied in an in vitro amino acid incorporation system. The ribosomes from the organism with moderately high-level streptomycin resistance were sensitive to streptomycin in vitro, suggesting that this type of resistance is caused by failure of streptomycin to reach the ribosomes. Very high-level resistance (and lack of penicillin-streptomycin synergism), on the other hand, appears to be due to ribosomally mediated streptomycin resistance.
Olfaction Modulates Reproductive Plasticity through Neuroendocrine Signaling in Caenorhabditis elegans

Reproductive plasticity describes the ability of organisms to adjust parameters such as volume, rate, or timing of progeny production in order to maximize successful reproduction under different environmental conditions. Reproductive plasticity in response to environmental variation has been observed in a wide range of animals; however, the mechanisms involved in translating environmental cues into reproductive outcomes remain unknown. Here, we show that olfaction modulates reproductive timing and senescence through neuroendocrine signaling in Caenorhabditis elegans. On their preferred diet, worms demonstrate an increased rate of reproduction and an early onset of reproductive aging. Perception of the preferred diet's odor by AWB olfactory neurons elicits these adjustments by increasing germline proliferation, and optogenetic stimulation of AWB neurons is sufficient to accelerate reproductive timing in the absence of dietary inputs. Furthermore, AWB neurons act through neuropeptide signaling to regulate reproductive rate and senescence. These findings reveal a neuroendocrine nexus linking olfactory sensation and reproduction in response to environmental variation and indicate the significance of olfaction in the regulation of reproductive decline during aging.
A State-Space Approach for Optimal Traffic Monitoring via Network Flow Sampling.

The robustness and integrity of IP networks require efficient tools for traffic monitoring and analysis, which scale well with traffic volume and network size. We address the problem of optimal large-scale flow monitoring of computer networks under resource constraints. We propose a stochastic optimization framework where traffic measurements are done by exploiting the spatial (across network links) and temporal relationship of traffic flows. Specifically, given the network topology, the state-space characterization of network flows and sampling constraints at each monitoring station, we seek an optimal packet sampling strategy that yields the best traffic volume estimation for all flows of the network. The optimal sampling design is the result of a concave minimization problem; then, Kalman filtering is employed to yield a sequence of traffic estimates for each network flow. We evaluate our algorithm using real-world Internet2 data.
A new NK1 receptor antagonist (CP-99,994) prevents the increase in tracheal vascular permeability produced by hypertonic saline.

The increase in tracheal vascular permeability evoked by hypertonic saline depends on capsaicin-sensitive sensory nerves, which contain substance P and other neuropeptides. The present study was performed to determine whether a novel, nonpeptide, selective antagonist of the NK1 tachykinin receptor CP-99,994, [(+)-(2S-3S)-3-(2-methoxybenzylamino)-2-phenylpiperidine], can prevent the effect of substance P, capsaicin and hypertonic saline on tracheal vascular permeability. CP-99,994 was also tested against a nonpeptide inflammatory mediator, platelet-activating factor (PAF), to assess the selectivity of its action. Anesthetized F-344 rats were injected with either substance P (5 micrograms/kg i.v.), capsaicin (100 micrograms/kg i.v.) or PAF (10 micrograms/kg i.v.), or were exposed to ultrasonically nebulized 3.6% NaCl. In each group, some of the rats were pretreated with CP-99,994 (1 to 4 mg/kg i.v.), and some with its vehicle (0.9% NaCl). Groups of rats injected with substance P or exposed to hypertonic saline were pretreated with the (2R, 3R)-enantiomer CP-100,263, [(-)-(2R-3R)-3-(2-methoxybenzylamino)-2-phenylpiperidine] (2 or 4 mg/kg i.v.). The magnitude of the increase in tracheal vascular permeability was measured by quantifying the extravasation of Evans blue dye. CP-99,994 prevented the increase in tracheal vascular permeability produced by inhalation of hypertonic saline, by substance P and by capsaicin, but did not prevent the effect of PAF. CP-100,263 did not affect substance P- and hypertonic saline-induced increase in vascular permeability. These results indicate that the NK1 receptor antagonist CP-99,994 produces stereoselective inhibition of neurogenic plasma extravasation evoked by inhalation of hypertonic saline.
Postcolonial Identities in Africa

Postcolonial Identities in Africa. Richard Werbner and Terence Ranger. eds. London: Zed Books, 1996. 292 pp.
Common blood flow changes across visual tasks: Ii. decreases in cerebral cortex

Nine previous positron emission tomography (PET) studies of human visual information processing were reanalyzed to determine the consistency across experiments of blood flow decreases during active tasks relative to passive viewing of the same stimulus array. Areas showing consistent decreases during active tasks included posterior cingulate/precuneous (Brodmann area, BA 31/7), left (BAS 40 and 39/19) and right (BA 40) inferior parietal cortex, left dorsolateral frontal cortex (BA S), left lateral inferior frontal cortex (BA 10/47), left inferior temporal gyrus @A 20), a strip of medial frontal regions running along a dorsal-ventral axis (BAs 8, 9, 10, and 32), and the right amygdala. Experiments involving language-related processes tended to show larger decreases than nonlanguage experiments. This trend mainly reflected blood flow increases at certain areas in the passive conditions of the language experiments (relative to a fixation control in which no task stimulus was present) and slight blood flow decreases in the passive conditions of the nonlanguage experiments. When the active tasks were referenced to the fixation condition, the overall size of blood flow decreases in language and nonlanguage tasks were the same, but differences were found across cortical areas. Decreases were more pronounced in the posterior cingulate/precuneous (BAS 31/7) and right inferior parietal cortex (BA 40) during language-related tasks and more pronounced in left inferior frontal cortex (BA 10/47) during nonlanguage tasks. Blood flow decreases did not generally show significant differences across the active task states within an experiment, but a verb-generation task produced larger decreases than a read task in right and left inferior parietal lobe (BA 40) and the posterior cingulate/precuneous (BA 31/7), while the read task produced larger decreases in left lateral inferior frontal cortex (BA 10/47). These effects mirrored those found between experiments in the language-nonlanguage comparison. Consistent active minus passive decreases may reflect decreased activity caused by active task processes that generalize over tasks or increased activity caused by passive task processes that are suspended during the active tasks. Increased activity during the passive condition might reflect ongoing processes, such as unconstrained verbally mediated thoughts and monitoring of the external environment, body, and emotional state.
Handoffs Between Radiologists and Patients: Threat or Opportunity?

Radiologists, referring physicians, and patients all have certain legal rights regarding access to medical records, including imaging data. The degree of patient access is likely to increase with the growing adoption of patient portals and personal health records. In addition, referring physicians and radiologists have a collective responsibility to ensure that important findings are transferred appropriately between their practices. In some cases when this is not possible, communicating directly with patients is the best way to protect the interests of both patients and radiologists. Even when not required, some radiologists have extensive experience communicating results directly to patients. Direct communication of radiology results to patients may present an opportunity to satisfy patients and reassert the importance of the physician-patient relationship in radiology.
Estimating the effect of wind loading on extremely large telescope performance using computational fluid dynamics

Wind loading is one of the critical parameters influencing the performance of large telescopes, with potentially more dramatic consequences for proposed future giant telescopes. This study describes a strategy for modeling the effects of wind loading on extremely large telescopes such as the Thirty Meter Telescope (TMT). The optical performance of the telescope is estimated by an integrated model, which incorporates the telescope structure, optics, and control. To model the dynamic force variation on the telescope, a Finite Element Analysis (FEA) model of the telescope is created along with an unsteady Computational Fluid Dynamics (CFD) model of the airflow around the enclosure-telescope configuration, which should have a suitable level of geometric fidelity. Numerical simulations using the CFD model are performed for a chosen wind speed and telescope orientation (azimuth, zenith), through which the dynamic force pattern on the primary and secondary mirrors as well as on the secondary support structure can be determined. Finally the force pattern is applied to the FEA model. This can be achieved either by applying temporally and spatially filtered white noise forces with random distribution deducted from the CFD analysis, or by considering the dynamic force pattern itself from the unsteady CFD calculations. Since the FEA and CFD models usually have different resolution requirements and consequently different, non-uniform spatial sampling grids, a key part of the interface is the conversions necessary to transfer the forces from CFD surface cells to structural nodes.
Reactive Uptake of Trimethylamine into Ammonium Nitrate Particles

The reaction of trimethylamine (TMA) vapor with a polydisperse distribution of ammonium nitrate particles (20−500 nm dia.) was studied in a flow tube reactor with particle analysis by laser desorption (1064 nm) 70 eV electron ionization (EI) in an ion trap time-of-flight (IT-TOF) aerosol mass spectrometer. When the TMA vapor concentration was very high, essentially complete exchange of TMA for ammonia in the particles was achieved. When the TMA vapor concentration was lower (∼500 ppb for a reaction time of 23 s), partial exchange was observed, and the initial reactive uptake coefficient was estimated to be on the order of 2 × 10−3 at 20% RH. This value suggests that measurable exchange is possible in the atmosphere when particles are exposed to an amine concentration on the order of 1 ppb for a few hours. The effects of particle size, water content, and amine molecular structure on uptake remain to be elucidated.
Modeling reactive transport using exact solutions for first-order reaction networks

Operator splitting is often used for solving advection-dispersion-reaction (ADR) equations. Each operator can be solved separately using an algorithm appropriate to its mathematical behavior. Although a lot of research has been done in operator splitting for solving ADR equations, numerical approaches for the reaction operator are computationally expensive. To meet the convergence criteria of ODE (ordinary differential equation) or DAE (differential algebraic equation) solvers, a transport time step has to be subdivided into a large number of reaction time steps. Additional computation effort is also required to reduce the splitting error. In this paper, we develop exact solutions of various first-order reaction networks for the reaction operator and couple those solutions with numerical solutions of the transport operator. The reactions are treated as local phenomena and simulated using exact solutions that we develop, while advection and dispersion are treated as global processes and simulated numerically. The proposed method avoids the numerical error from the reaction operator and requires a single-step calculation to solve the reaction operator. Compared to conventional operator-splitting methods, the proposed method offers both computational efficiency and simulation accuracy.
Application of Gratings in a Dielectric Waveguide for Leaky-Wave Antennas and Band-Reject Filters (Short Papers)

Grating structures fabricated in inverted-strip dielectric waveguides have been used for the first time as leaky-wave antennas and band-reject filters. They are potentially useful for millimeter-wave integrated circuits. Experimental results agree reasonably well with theoretical predictions.
Effects of chronic chlorisondamine administration on the sympatho-adrenal axis.

Abstract The chronic administration of chlorisondamine, a ganglionic blocking agent, for periods up to 1 week produced dose-dependent increases in rat adrenal catecholamines (CA), tyrosine hydroxylase TH) activity and dopamine β-hydroxylase (DBH) activity, and also increased plasma levels of circulating DBH. Uptake of [ 3 H]epinephrine into isolated adrenal medullary storage vesicles from rats given chlorisondamine was reduced compared to controls. Prior denervation of the adrenal eliminated the chlorisondamine-induced increases in CA and TH, and reduced but did not eliminate the increases in DBH. Atropine pretreatment did not reduce the stimulatory effects of chlorisondamine. Ganglionic blockade was effective throughout the period of chronic chlorisondamine administration. as confirmed by the failure of insulin to evoke CA secretion even when given at the longest time period between chlorisondamine injections. These data suggest that chlorisondamine produces a mixture of direct and trans-synaptic sympatho-adrenal stimulation as well as ganglionic blockade, and that the mixed effect persists upon chronic administration.
The Impact of Welfare Reform Policies on Child Protective Services: A National Study

The 1996 welfare reform bill set forth major changes in social welfare policies. In addition to federal work requirements and time limits, new state policies impose behavioral mandates that may be accompanied by financial sanctions for noncompliance. Analysis of a survey of state Child Protection Services (CPS) directors focuses on four major areas: effect of Temporary Assistance to Needy Families (TANF) on CPS; interaction between the two agencies; role of TANF sanctions in referrals to CPS; and select special areas of concern. This research provides empirical insight into the interaction between these two agencies, specific TANF sanctions, and the potential conflicts between TANF policies and CPS concerns for the welfare of children and families under its charge.
Initial coupling of coronal and heliospheric numerical magnetohydrodynamic codes

Coupling of coronal and heliospheric magnetohydrodynamic (MHD) codes represents an efficient modular approach to numerical simulations of physical phenomena occurring on different spatial and temporal scales. Using specialized models makes it possible to: (1) treat efficiently the very different physics relevant in coronal and interplanetary regimes; (2) deal with different time-step constraints for coronal and heliospheric simulations; and (3) optimize and update individual system components with the latest understanding. We present results on the coupling of coronal and heliospheric numerical MHD codes developed within the Center for Integrated Space weather Modeling. We discuss 2-D parametric studies conducted to verify the computational coupling procedure and to assess the accuracy of merging physically and numerically different models.
Continuous monitoring of aerosols over the 0.001- to 10-micron spectrum.

Abstract Three aerosol sizing and counting instruments were combined into a single automatic system capable of continuously providing data pertinent to the physical properties of airborne particulates. Particle sizes are determined by either condensation, light scattering, or electrical phenomena. All three methods are required to measure broad-size aerosol spectrums, as each individual method possesses accurate sizing characteristics over a limited size range. The instruments, combined into a unitized system, provide data on particles within various interval widths and group the respective sized particles according to the interval midpoint. An appropriate electrical signal, indicative of the number of particles present, is recorded by electronic instrumentation, and subsequent calculations result in a complete number-size distribution. This paper describes the union of the condensation nuclei counter, the light-scattering counter, and the electrical particle counter with associated data acquisition equip...
Energy Recovery From Municipal Solid Wastes by Gasification

Recovery of energy from MSW by combustion in Waste-to-Energy (WTE) plants reduces landfilling and air/water emissions, and also lessens dependence on fossil fuels for power generation. The objective of this study was to assess the potential of gasification processes as an alternative to the combustion of MSW. Gasification uses a relatively small amount of oxygen or water vapor to convert the organic compounds into a combustible gas. Its advantages are a much lower volume of process gas per unit of MSW and thus smaller volume of gas control equipment; also, gasification generates a fuel gas that can be integrated with combined cycle turbines or reciprocating engines, thus converting fuel energy to electricity more efficiently than the steam boilers used in combustion of MSW. The disadvantages are the need to pre-process the MSW to a Refuse Derived Fuel (RDF) and the formation of heavy organic compounds (tars), that may foul the downstream gas cleaning and energy conversion systems. This paper presents two prominent gasification processes and compares their energy characteristics with a mass burn WTE and a suspension firing WTE that uses shredded WTE. The results showed potential energy and capital cost advantages for gasification. However, the operational difficulties experienced at several pilot and demonstration plants indicate that long-term operating results from a large industrial plant are needed before gasification can be considered a reliable alternative to combustion. The Gasification Process
Saturable Inductor Based Controlled Waveform Excitation Source for Exploding Thin Film Atomic Spectroscopy

An adjustable waveform excitation source for exploding thin film atomic spectroscopy is described. Waveform control is achieved through a saturable inductor having control windings and placed in series with the underdamped discharge tank circuit. This results in a high-current pulse for efficient sample atomization followed by a low-current measurement interval. When this is combined with gated integration, ∼15-fold increases in analysis line/background intensity ratios are observed for V and Mn. With additional inductance added to the circuit, the current and duration of both the atomization pulse and measurement interval can be adjusted independently. Other features of the excitation source include a plasma shunt capacitor, which results in more reproducible dielectric breakdown of the plasma support gas, and a variety of high-current series switches for initiating the discharge. Triggered spark gap, gravity operated spark gap, silicon-controlled rectifier, and ignitron switches are compared with respect to resistance and switching time jitter. Examples of discharge current and voltage waveforms and preliminary analytical data are presented.