cssi/SciSciGPT-SciSciNet huggingface dataset:
Modeling and FEM Verification of Surface-Roughness Effect on the Static Response of RF-MEMS Switches

Radio Frequency Microelectromechanical systems (RF MEMS) are being employed in various commercial and military applications. However, the reliability of the switches still remains a matter of concern. During design phase of the RF MEMS switches, the surfaces of switch are considered to be smooth at micro scale and the effect of surface roughness is neglected. The theme of the present paper is to quantify surface roughness effect on the static pull in voltage and gap of an electrostatically actuated RF MEMS switches by providing a simple analytical model along with the FEM (Finite Element Modeling) simulations. The surface roughness effect on the static pull in voltage of RF-MEMS capacitive switches becomes severe in case of small distance between the suspended top bridge and bottom dielectric. The results in the paper shows that the value of pull in voltage and gap decreases whereas value of capacitance increases as radius of spherical surface roughness increased. The pull in voltage value of the capacitive switch for an air gap thickness of $0.5\ \boldsymbol{\mu} \mathbf{m}$ and $2.5\ \boldsymbol{\mu} \mathbf{m}$ decreases by approximately 27% and 23% from its smooth surfaced value for a roughness scale of $0.1\ \boldsymbol{\mu}\mathbf{m}$ respectively. The results are important for the search of an ideal switch and are in good agreement with the mathematical model.
Long-term effects of experimental nitrogen additions on foliar litter decay and humus formation in forest ecosystems

Decomposition rates and N dynamics of foliar litter from 4 tree species were measured over a 72 month period on the Chronic Nitrogen Addition plots at the Harvard Forest, Petersham MA, beginning in November 1988. Plots received nitrogen additions of 0, 5 and 15 g N m-2yr-1 in two different stand types: red pine and mixed hardwood. Bags were collected in August and November of each year and litter analysed for mass remaining, nitrogen, cellulose and lignin content. Mass remaining was significantly greater for litter in nitrogen treated plots than in control plots after 48 months. Lignin content of litter was significantly higher with nitrogen treatments but there was little effect of treatment on cellulose content. N concentration was similar between treatments, but greater mass remaining in treated plots resulted in a higher total amount of N in humus produced in the high N plot. This mechanism could be a sink for up to 1.5 g N·m-2yr-1 of the 1.5 g N·m-2yr-1 added annually to the high N plots. Reduced decomposition rates in conjunction with increased lignin accumulation could impact global carbon sequestration as well.
Medical and Surgical Uses of the Prepuce

The human prepuce is a highly specialised tissue which plays a fundamental role in the general aspect of the external genitalia. Beside its natural protective, mechanical, immunological and erogenous functions, it also represents a valid source of tissue in various conditions and is considered a reservoir of regenerative cells. The aim of the present chapter is to provide an overview of its possible uses in order to highlight its importance for both medical and surgical purposes.
Cesium-131 prostate brachytherapy: A single institutional long-term experience.

Abstract Aims To report on the PSA outcomes in men undergoing prostate seed implant (PSI) with Cesium-131 at a single institution. Materials and Methods All patients who underwent prostate brachytherapy with Cesium-131 (131Cs) at our institution and had the potential for at least 24 months of follow up were included in this study. Results are reported for the by NCCN risk group (low, low/high-intermediate, and high), as well as by treatment received (monotherapy, combination external beam radiation + PSI, or trimodal therapy with androgen deprivation). The Phoenix definition (absolute nadir plus 2 ng/mL) was used to define biochemical freedom from disease (BFD). Results Eight hundred and six men have undergone prostate brachytherapy with Cesium-131 at our institution, and 669 men were included in analysis. Median follow up was 60.0 months (range: 0–144 months). According to NCCN risk categories, 29.9% were low-, 55.6% intermediate-, and 14.5% high-risk. Using the Phoenix criteria, 5/10-year BFD was 97.1/95.3% for patients in the low-risk category, 94.0/90.1% for patients in the intermediate-risk category, and 86.2/56.6% for patients in the high-risk category. PSA ≤0.2 ng/dL at 4 years was predictive of 10 year biochemical control: 96.3% vs 70.4%, p Conclusions The present study demonstrates that prostate brachytherapy with 131Cs achieves excellent long-term biochemical control.
Chapter 45 – Neurosarcoidosis

Publisher Summary The chapter presents a discussion on neuroarcoidosis. Sarcoidosis is a disease of unknown etiology featured pathologically by noncaseating granulomas. The diagnosis is most secure if inflammation can be documented in multiple organ systems. Sarcoidosis most commonly affects intrathoracic structures. Neurologic disease develops in five percent of patients with sarcoidosis. The chapter outlines the different neurologic manifestations of sarcoidosis and selected differential diagnostic considerations. Patients with known systemic sarcoidosis who develop an illness compatible with the neurologic manifestations of sarcoidosis should be evaluated to reasonably exclude other disease entities, particularly infection and neoplasia. If the patient does not respond as expected to treatment for neurosarcoidosis, the diagnosis should be questioned and a more extensive diagnostic evaluation pursued. If a patient without documented sarcoidosis develops an illness compatible with neurosarcoidosis, the patient should be evaluated for multisystem inflammation. Sarcoidosis mostly affects the lungs, lymph nodes, skin, and eyes. Ocular findings include lacrimal gland inflammation, conjunctival nodules, iritis, uveitis, retinal lesions, and optic disc pathology. The preferred imaging modality to evaluate central nervous system (CNS) sarcoidosis is a gadolinium-enhanced magnetic reasonance imaging (MRI). The chapter discusses peripheral facial nerve palsy, chronic corticosteroid therapy, and several other alternative medications.
Bacterial Infections of the Spine

Spine infections are a group of heterogenous clinical entities resulting from hematogenous seeding or direct inoculation of microrganisms into the various anatomical elements of the spinal column. They encompass discitis, spondylodiscitis, septic facet joints and epidural abscesses. An unacceptably long diagnostic delay remains a major challenge in spine infections, despite significant advancement in imaging and therapeutic modalities. C-reactive protein is a helpful marker in shortening the diagnostic delay. Empiric antimicrobial therapy should be withheld in hemodynamically stable patients without major neurological deficits. The proportion of spine infections managed conservatively, with antimicrobial agents only, is on the rise. Clear indications for surgery include neurological deficits caused by compression of the spinal cord and mechanical instability. Though mortality rates have improved, it remains a clinical entity with significant long-term morbidity.
Vitamin E delta-tocotrienol and metabolite 13'-carboxychromanol inhibit colitis-associated colon tumorigenesis and modulate gut microbiota in mice

The gut microbiota play important roles in colon cancer. Vitamin E δ-tocotrienol (δTE) and its metabolite δTE-13'-carboxychromanol (δTE-13') are known to have cancer-preventive effects, but their impact on gut flora during tumorigenesis and the role of the metabolite in δTE's beneficial effects remain to be determined. In the murine colitis-associated colon cancer (CAC) induced by azoxymethane (AOM) and dextran sulfate sodium (DSS), we show that δTE and δTE-13' inhibited the multiplicity of large adenomas (>2 mm2) by 34% (P<.05) and 55% (P<.01), respectively, compared to the control diet. δTE-13' diminished AOM/DSS-increased GM-CSF and MCP-1, and δTE decreased IL-1β. Using 16S rRNA gene sequencing of fecal DNAs, we observe that δTE and δTE-13' modulated the composition but not the richness of gut microbes compared to the control. Both δTE and δTE-13' enhanced potentially beneficial Lactococcus and Bacteroides. The elevation of Lactococcus positively correlated with fecal concentrations of δTE-13' and its hydrogenated metabolite, suggesting that the metabolite may contribute to δTE's modulation of gut microbes. Furthermore, δTE-13' counteracted AOM/DSS-induced depletion of Roseburia that is known to be decreased in patients with inflammatory bowel diseases. δTE uniquely elevated (Eubacterium) coprostanoloigenes. Our study demonstrates that δTE and δTE-13' inhibited tumorigenesis, suppressed pro-inflammatory cytokines and modulated gut microbiota in a murine CAC model. These findings uncover new and distinct activities of δTE and δTE-13' and support the notion that the metabolite may play a role in δTE's anticancer and modulation of gut microbes.
PRIORITY VECTOR ESTIMATION: CONSISTENCY, COMPATIBILITY, PRECISION

Various methods of priority vector estimation are known in the Analytic Hierarchy Process (AHP). They include the classical eigenproblem method given by Thomas Saaty, developments in least squares and the multiplicative approach, robust estimation based on transformation of the pairwise ratios to the shares of preferences, and other approaches. In this paper, the priority vectors are completed with validation of data consistency, comparisons of vectors’ compatibility, and estimation of precision for matrix approximation by vectors. The numerical results for different data sizes and consistency show that the considered methods reveal useful features, are simple and convenient, and capable of facilitating practical applications of the AHP in solving various multiple-criteria decision making problems.
Regional multi-environment analysis of corn productivity and yield stability as impacted by hybrid maturity

Abstract Corn (Zea mays L.) hybrid maturity selection can help maximize productivity, yield stability, and optimize the use of available resources such as water, solar radiation, and nutrients. We explored yield differences by hybrid maturity with long term data from corn hybrid performance tests conducted between 2005 and 2017 in three U.S. states with variable area under irrigation: Arkansas (AR; 50 environments, 100% irrigated), Nebraska (NE; 22 environments, 59% irrigated), and Kentucky (KY; 54 environments, all rainfed). Stability-analysis techniques and probability functions were used to test the effect of Corn Relative Maturity (CRM) on yield and yield stability. Average yields increased per unit increase in CRM group by 51 kg ha−1 CRM−1 in AR and 122 kg ha−1 CRM−1 in NE. Thus, hybrids maturity recommendations to maximize yield were the latest CRM groups included in Corn Performance Tests in AR and NE (CRM 118−120 and 115−118, respectively). In contrast, the yield response to CRM group showed a quadratic relationship in KY, and selecting CRM groups later than 109–114 would reduce yield stability and likely delay harvest without providing a significant yield advantage. Full-season hybrids in AR and NE also showed the greatest responsiveness to environments of increasing average productivity, unlike in KY where all CRM groups showed similar responses. Different results observed across the three states may be partially attributed to different percentage of irrigated sites, with the implication that optimum hybrid maturity recommendations may need to be redefined depending on water availability.
Practice among Healthcare Workers Regarding the Use of Respiratory Protective Equipment during COVID-19 Pandemic in a Tertiary Care Center: A Descriptive Cross-sectional Study

Introduction: Healthcare workers are always at the risk of exposure to different diseases like respiratory illness including COVID-19. Using appropriate face mask or respiratory protective equipment correctly can prevent transmission of diseases from and to healthcare workers while caring for patients. The study aimed to find out the practice regarding use of face masks during the COVID-19 pandemic in a tertiary care center. Methods: A descriptive cross-sectional study was conducted at a tertiary care hospital during June-July 2020 after receiving ethical approval from the review committee regarding practice of use of face masks. Convenience sampling method was used and a sample size of 162 was taken. Descriptive statistical analysis was done. Point estimate at 95% Confidence Interval was calculated along with frequency and proportion for binary data. Results: Among 162 participants, 123 (75.9%) knew the correct way of using the masks (72.5-79.3 at 95% Confidence Interval). Conclusions: In this study regarding practice of use of face masks, most of the healthcare workers knew the correct way of using masks and practised hygiene before and after using masks.
The relationship between phthalate risk score and gestational age at delivery is mediated by cytochrome p450 derived eicosanoids: application of a novel analytical pipeline for high-dimensional multivariate mediation analysis

Background: There are diverse toxicological mechanisms that may mediate the impact of several toxicant classes (phthalates, phenols, polycyclic aromatic hydrocarbons, and metals) on pregnancy outco...
Nonalcoholic Steatohepatitis — Opportunities and Challenges

Nonalcoholic steatohepatitis (NASH), the progressive form of nonalcoholic fatty liver disease, has superseded hepatitis C as the main cause of cirrhosis and the main reason for liver transplantatio...
The Serendipity of Viral Trans-Neuronal Specificity: More Than Meets the Eye.

Trans-neuronal viruses are frequently used as neuroanatomical tools for mapping neuronal circuits. Specifically, recombinant one-step rabies viruses (RABV) have been instrumental in the widespread application of viral circuit mapping, as these viruses have enabled labs to map the direct inputs onto defined cell populations. Within the neuroscience community, it is widely believed that RABV spreads directly between neurons via synaptic connections, a hypothesis based principally on two observations. First, the virus labels neurons in a pattern consistent with known anatomical connectivity patterns. Second, few glial cells appear to be infected following RABV injections, despite the fact that glial cells are abundant in the brain. However, there is no direct evidence that RABV can actually be transmitted through synaptic connections. Here we review the immunosubversive mechanisms that are critical to RABV’s success for infiltration of the central nervous system (CNS). These include interfering with and ultimately killing migratory T cells while maintaining levels of interferon (IFN) signaling in the brain parenchyma. Finally, we critically evaluate studies that support or are against synaptically-restricted RABV transmission and the implications of viral-host immune responses for RABV transmission in the brain.
Where to Turn for Help: Responses to Inadequate Clinical Supervision

Abstract This article addresses issues pertaining to the experience of trainees who encounter deficient supervision. The pertinent literature concerning insufficient supervision is reviewed, and a case example is described in which deficient supervision resulted in tragic consequences. Ethical considerations and implications are discussed, and recommendations are offered to trainees who find themselves working in clinical contexts in which supervision is lacking.
Concept visualization in CS0 using ALICE

CS0 provides non-major and pre-major students with a tour of computing, touching the big ideas and their implications. The most important idea, arguably, is the algorithm and its implementation as a program. Deep treatment in a limited time (three weeks) for these students is challenging at best. We describe six Alice virtual worlds that engage students and illustrate a set of important algorithm concepts. These example worlds act as a springboard for students to construct their own. Assessments from students and faculty indicate that learning about algorithms is as effective and potentially more engaging for novice computing students; however, technical issues are distracting at present.
Adventures in cubic curve fitting: two optimization techniques and their application to the training of neural networks

Presents two optimization techniques based on cubic curve fitting; one based on function values and derivatives at two previous points, and another based on derivatives at three previous points. The latter approach is viewed from a derivative space perspective, obviating the need to compute the vertical translation of the cubic, thus simplifying the fitting problem. The authors demonstrate the effectiveness of the second method in training neural networks on parity problems of various sizes, and compare their results to a modified Quickprop algorithm and to gradient descent. >
Learning topological maps with weak local odometric information

Topological maps provide a useful abstraction for robotic navigation and planning. Although stochastic maps can theoretically be learned using the Baum-Welch algorithm, without strong prior constraint on the structure of the model it is slow to converge, requires a great deal of data, and is often stuck in local minima. In this paper, we consider a special case of hidden Markov models for robot-navigation environments, in which states are associated with points in a metric configuration space. We assume that the robot has some odometric ability to measure relative transformations between its configurations. Such odometry is typically not precise enough to suffice for building a global map, but it does give valuable local information about relations between adjacent states. We present an extension of the Baum-Welch algorithm that takes advantage of this local odometric information, yielding faster convergence to better solutions with less data.
The Spirit, Creaturehood and Sanctification: On Avoiding Theological Overcompensation

Talk of the Spirit's work of sanctification often leads to a number of different conclusions, ones that often appear mutually exclusive. Under such conditions, their espousers often make cases for their views in overcompensatory ways by highlighting their approaches over and against other views that may be complementary in their own way. This article contends that behind this diversity are often competing claims within different domains of inquiry surrounding the Creator–creation interface. These commitments lurk in the background of these debates, and their exposure may help in the ongoing task of speaking of the Spirit's endeavoring in and among creatures.
Changing epidemiology and predictors of mortality in patients with spontaneous bacterial peritonitis at a liver transplant unit.

Objectives To determine whether antimicrobial resistance in pathogens and outcome in patients with spontaneous bacterial peritonitis (SBP) has evolved over time. Methods Sixty-one consecutive episodes of SBP were studied in patients with end-stage liver disease undergoing evaluation for liver transplantation between 1991 and 2001. Patients were dichotomized into a cohort between 1991 and 1995 (the earlier cohort) and 1996–2001 (the later cohort). Results Overall, 19% of all bacteria were multiply-antibiotic resistant. The frequency of multiple-antibiotic resistance in bacteria increased from 8.3% to 38.5% in the earlier as compared to the later cohort ( P = 0.07). Overall, mortality at 30 days in the study patients was 26% and had remained unchanged between the two cohorts. The mortality rate was significantly higher in patients with multiply-antibiotic-resistant bacteria than in those with other bacteria ( P = 0.045). However, the Child–Pugh score ( P = 0.003), and renal failure ( P = 0.04) were the only independently significant predictors of mortality in patients with SBP. Conclusions Mortality in patients with end-stage liver disease who developed SBP has remained unchanged over the last decade. Although multiple-antibiotic resistance in bacteria causing SBP has increased over time, the severity of hepatic and renal dysfunction were the predominant determinants of outcome in these patients.
The Place of Microbiology in Soil Science

Publisher Summary Soil science is a microbiological science, because in the multifarious processes involved in soil genesis, nutrient release, physical structure, and organic matter transformation, microorganisms are involved directly. If soil science is a microbiological science, then microbiology should be all pervading in soil science, without which it would be incomplete and largely inexplicable. With the recognition that many of the activities of organisms in the soil would be reflected in the supply of nitrogen to plants, attempts are made to express the fertility of soils in terms of its ability to carry out particular transformations, for example, ammonification, this being assessed by the rate of liberation of ammonia from a peptone solution inoculated with the particular soil sample. Most soil organisms possess a wide range of enzymes or have the capability of developing adaptive systems when presented with an unusual, alien, or exotic energy source. The versatility of a population is, therefore, astonishing, all the more so perhaps because soil is a beneficent environment for inactive forms, which maintain viability through long periods of inactivity. The net effect is that a soil can be treated experimentally as if it were a simple organism or a tissue, the capability of which to utilize any compound or group or compounds can be determined.
Rhetorical Obstacles In The Teaching Of Economics

If economics were to be a science like physics, its instruction would include labs. If economics were to be a branch of mathematics, its instruction may stress problem solving. But what if economics represents a way of thinking? What if learning economics is more like learning a language?
Strategies in the management of acute myocardial infarction

Clinical trials continue to evaluate the pharmacologic management of myocardial infarction for benefits in mortality, degree of infarct artery patency, and frequency of reocclusion. The discovery of thrombus formation in the development of the myocardial infarction renewed interest in thrombolytic therapy. In appropriate candidates, timely administration of thrombolytics after myocardial infarction restores coronary artery patency, reduces myocardial ischemic damage, and improves left ventricular function. Adjunct therapy for thrombolysis typically includes aspirin, heparin, beta-blockers, nitroglycerin, and angiotensin-converting enzyme inhibitors, if not contraindicated. To reduce cardiac risk, postthrombolysis management generally includes aspirin. beta-blockers, and angiotensin-converting enzyme inhibitors together with efforts to reduce known cardiovascular risk factors.
In-situ X-ray diffraction study of the decomposition of NaAlH4

Abstract Phase transitions and crystal structure modifications were observed during the thermal-desorption decomposition of the alanate NaAlH 4 . This was accomplished through the use of in-situ X-ray powder diffraction. A sequence of θ –2 θ scans were collected while heating the sample under a vacuum. The resulting diffraction patterns were assembled to provide a real-time representation of the decomposition reactions. It was found that upon heating, NaAlH 4 initially experienced a lattice expansion principally in the c -axis direction. This was followed by continuous structural distortions observed as erratic variations in the Bragg intensities. Melting of NaAlH 4 was observed at 180°C followed by the rapid precipitation of a cubic Na 3 AlH X phase. This phase then underwent a slow transformation into a Na-rich cubic phase. The decomposition of NaAlH 4 doped with a double catalyst (Ti+Zr) was also investigated. The uncatalyzed sample showed no decomposition when held under a vacuum at 150°C for several hours. The catalyzed sample, on the other hand, began to decompose readily into the monoclinic (α)-Na 3 AlH 6 phase when heated to 100°C in vacuum. At 150°C the (α)-Na 3 AlH 6 phase decomposed in a second reaction according to α-Na 3 AlH 6 →3 NaH+Al+3/2 H 2 . The two decomposition reactions appear to be interdependent as the second transformation commenced only after the first reaction neared completion. The observed growth of a narrow Al (111) diffraction peak indicates the formation of aluminum crystallites (>100 nm) as a part of the decomposition reactions. This, and the fact that this solid state process is assisted through the interaction of a surface catalyst suggests long-range transport of a metal species. Some mechanisms are proposed to explain the catalytically enhanced kinetics of these materials.
Communication therapy for the young adult.

Abstract Speech clinicians are often frustrated in their assessment and therapeutic management of a young adult with speech and language problems. Procedures for children with language disorders and aphasic adults are often inadequate for the adult who has communication impairments that cannot be attributed to aphasia. This case study presents an account of a 29-year-old woman who had cognitive, linguistic, and pragmatic difficulties. Both diagnosis and therapy were based on recent innovations in the areas of cognition, linguistics, and interpersonal relations. Results indicated that therapy was successful when the client was responsible for therapy activities, when therapy combined tutorial as well as experiential sessions, and when each session focused on the development of cognitive, linguistic, and interpersonal domains. Specific examples of diagnostic and therapeutic activities are presented as well as the rationale underlying the approach to therapy.
Transverse Bars and Braiding in the Lower Platte River, Nebraska

The Platte is a wide, shallow river which flows eastward from the Rocky Mountains across the Great Plains of Nebraska. Its lower reaches carry a dominantly sandy load and during intermediate and low discharges display a pronounced braided character accomplished primarily through dissection of tabular, flat-topped transverse bars. Transverse bars form by sediment aggrading to a profile of equilibrium (Jopling, 1966) and grow by downcurrent extensions of avalanche faces. Depth, velocity, and grain size tend to decrease on active bar surfaces from their upstream mouths to the downstream and lateral margins. Active surfaces are covered with small-scale bed forms whose distributions are controlled by the flow characteristics. A typical mouth-to-margin bed form progression is dunes to diminished dunes to ripples, reflecting downcurrent reduction of stream power. Water-surface slopes over active bars tend to be greater than those of the channel segments which feed them. Under ideal conditions, transverse bars are essentially lobate; however, most bars, especially during low discharges, assume irregular or asymmetrical patterns due to any of several factors that include bar-mouth cross-sectional geometry, proximity to exposed banks, adjacent currents, steadiness of flow, and basin depth distribution. Braiding (bar dissection) begins during decreasing discharges when the flow passing through the bar mouth becomes unable to sustain active sediment transport over the entire bar surface. A single bar, examined closely over a five-day period of gradually decreasing discharge, documents the evolution from wholly active to dissected states.
Local structure of interstitial Zn in β‐Zn4Sb3

The low thermal conductivity of the thermoelectric material β-Zn_4Sb_3 has been linked to disorder arising from multiple interstitial Zn sites. Here we investigate the energetics and local distortions associated with these interstitial sites via DFT calculations. Our results show the β-Zn_4Sb_3 structure is able to distort into many inequivalent geometries of similar energies, suggesting a topology rich with transport pathways through energetically accessible metastable states. The occurrence of such a shallow energy landscape may explain the recently discovered liquid-like diffusivity of Zn in β-Zn_4Sb_3 – comparable to that found in superionic conductors.
Immunohistochemical analysis of the stage-specific expression of Ia antigens in the rat mammary gland during pregnancy and lactation.

Abstract The expression of Class II MHC antigens in the rat mammary gland was assessed by immunoperoxidase using monoclonal antibodies against rat homologues of the murine I-A and I-E antigens. Our results showed that, while I-A and I-E were inconspicuous in undifferentiated mammary epithelium in virgin rats, during early pregnancy, the ductal epithelium becomes intensely positive for both antigens. A monoclonal antibody specific for macrophages showed that they were abundant in the stroma but did not correspond to the epithelial staining. During late pregnancy and lactation, the ductal epithelium expressed varying levels of Ia, while the alveolar epithelial cells were consistently Ia-negative. Ia-positive mononuclear cells of round or dendritic morphology present in the alveolar areas were enummerated as cells per high power field (HPF). Maximal cell counts for I-A and I-E were seen in late pregnancy and early lactation, with a significant decline in mid-lactation. Counts were higher in intraepithelial locations than in the subjacent connective tissue at all stages. The possible role of these stage-specific alterations in regulating local immune responses and transfer of immune components into milk is discussed.
Ingmar Bergman’s The Virgin Spring: Cultures in conflict

Based on a medieval Swedish ballad that tells the story of a young maiden raped and murdered on her way to church, and of her father’s revenge and subsequent promise to build a Christian church at ...
Fish Discoveries by the Lewis and Clark and Red River Expeditions

Abstract The Lewis and Clark Expedition of 1804–1806 and the Red River Expedition of 1806 were two early explorations of the land acquired by the United States in the Louisiana Purchase in western North America. They were the first such western excursions to include natural history investigations as part of the trip objectives—a reflection of Thomas Jefferson's strong scientific curiosity. Whereas Lewis and Clark were briefly trained but conscientious amateurs, the Red River party included naturalist Peter Custis. Both expeditions discovered new species of fishes, which were later formally described by others, but the detailed descriptions of the Lewis and Clark Expedition are much more useful to modern ichthyologists than the simple, often erroneous, identifications of a trained naturalist of the day.
Improving adolescents' standardized test performance: An intervention to reduce the effects of stereotype threat

Standardized tests continue to generate gender and race gaps in achievement despite decades of national attention. Research on ‘‘stereotype threat’’ (Steele & Aronson, 1995) suggests that these gaps may be partly due to stereotypes that impugn the math abilities of females and the intellectual abilities of Black, Hispanic, and low-income students. A field experiment was performed to test methods of helping female, minority, and low-income adolescents overcome the anxiety-inducing effects of stereotype threat and, consequently, improve their standardized test scores. Specifically, seventh-grade students in the experimental conditions were mentored by college students who encouraged them either to view intelligence as malleable or to attribute academic difficulties in the seventh grade to the novelty of the educational setting. Results showed that females in both experimental conditions earned significantly higher math standardized test scores than females in the control condition. Similarly, the students—who were largely minority and low-income adolescents—in the experimental conditions earned significantly higher reading standardized test scores than students in the control condition. D 2003 Published by Elsevier Inc.
Imiquimod and lentigo maligna: a search for prognostic features in a clinicopathological study with long-term follow-up.

Summary Background Melanoma in situ/lentigo maligna (LM) is a potential precursor of LM melanoma. It occurs most commonly in elderly individuals on sun-exposed skin of the head and neck. Although surgical excision is the treatment of choice, this may not be desirable or feasible for large lesions at functionally or cosmetically important sites. Imiquimod is a topical immunomodulator which can generate a local cytotoxic response with potentially antiviral and antitumour effects. Objectives To present our experience of LM treated with imiquimod. Methods A retrospective review was performed of all patients with facial LM treated in our unit with topical imiquimod between January 2001 and December 2006. Pretreatment diagnostic biopsies were also reviewed and histologically graded. Results Forty-eight patients were treated with imiquimod. There were 37 responders and 11 treatment failures (of whom two were ‘partial responders’). Of the 37 responders, 31 showed a clinical inflammatory response to imiquimod. One patient in whom treatment failed subsequently developed invasive disease. The mean follow-up duration was 49 months. We could not identify histological features of prognostic significance. However, the ability to develop an inflammatory reaction to imiquimod was a strong predictor of therapeutic benefit. Conclusions We consider imiquimod to have a role in the treatment of LM in patients in whom surgery may be contraindicated or for those in whom the cosmetic or functional consequences may be considerable. Until better characterized, its use should probably be confined to centres with experience in the detection and treatment of LM and melanoma.
Genetic analysis of embryonic patterning mechanisms in the beetleTribolium castaneum

Abstract Genetic analysis has been a powerful tool for dissecting the patterning mechanisms that define the embryonic axes ofDrosophila melanogaster. Mutants that alter embryonic patterning in a more primitive insect will provide insights into patterning mechanisms that do not occur in Drosophila.Tribolium castaneum, the red flour beetle, generates body segments after the blastoderm stage, like primitive insects, and is amenable to genetic analysis. We review the tools of Tribolium genetics and describe the kinds of mutant screens that have been carried out in Tribolium. Allele screens and reversion screens of spontaneous homeotic mutations have isolated embryonic lethal alleles of homeotic genes. The phenotypes of these mutations reveal changes in homeotic gene function between Drosophila and Tribolium. We have screened directly for Tribolium patterning mutants by looking for changes in the first instar larval cuticle pattern. The phenotypes of these mutants shed light on segmentation mechanisms that may be characteristic of primitive insects.
Retire the Hybrid Atomic Orbital? Not So Fast

This letter is a response to Alexander Grushow’s article, “Is It Time To Retire the Hybrid Atomic Orbital?” This letter suggests reasons for why valence bond theory and the associated hybrid atomic orbitals should continue to be taught in the chemistry curriculum.
STUDIES ON SHEEP GRAZING IN THE NORTHERN PENNINES

The sheep grazing intensity and herbage intake on 3 high-level grasslands above 2250 ft were investigated. The seasonal intake, which varied from 450 to 700 lb dry matter/acre, was obtained by the yield-difference method, using cages moved monthly.
Determining an optimal time interval for testing and debugging software

A decision-theoretic procedure for determining an optimal time interval for testing software prior to its release is proposed. The approach is based on the principles of decision-making under uncertainty and involves a maximization of expected utility. Two plausible forms for the utility function, one based on costs and the other involving the realized reliability of the software, are described. Using previous results on probabilistic models for software failure, the ensuing optimization problem (which can be addressed using numerical techniques) is outlined for the case of single-state testing. The sensitivity of the results to the various input parameters is discussed, and some directions for future research are outlined. >
Conditions for zeros in the generalized oscillator strength: One-electron atom and diatomic molecule examples.

Requirements for the existence of isolated zeros in the generalized oscillator strength (GOS) for one-electron atoms and molecules are considered. It is shown that in certain limits the atomic GOS cannot be zero for any value of the momentum-transfer magnitude \ensuremath{\Elzxh}K\ensuremath{\ne}0 unless it is zero for all values. A relationship between the existence of a zero and the angular momentum of the target's states is pointed out for the atomic case and a numerical example is provided. The conditions for the existence of an isolated zero for a molecular GOS are derived and, using the atom case as a model, they indicate that one is unlikely for 0K\ensuremath{\infty} and the internuclear separation R restricted to 0R\ensuremath{\infty}. Minima, or possibly zeros, in the molecular GOS occur in both experiment and theory. It is postulated here that these structures are minima and not zeros. They appear to be due to zeros in a matrix element related to the leading term of the small-K GOS expansion while higher terms remain finite. Several numerical examples are provided and the speculation is supported by the correlation of the GOS minimum as a function of K and R to a zero in the dipole oscillator strength. Attention is brought to the existence of zeros in the molecular dipole oscillator strength when a nodeless function appears in this matrix element, contrary to the atomic case, and an explanation for this difference is given.
Polysomnographic Features of Sleep Disturbances and REM Sleep Behavior Disorder in the Unilateral 6-OHDA Lesioned Hemiparkinsonian Rat.

Sleep pattern disruption, specifically REM sleep behavior disorder (RBD), is a major nonmotor cause of disability in PD. Understanding the pathophysiology of these sleep pattern disturbances is critical to find effective treatments. 24-hour polysomnography (PSG), the gold standard for sleep studies, has never been used to test sleep dysfunction in the standard 6-OHDA lesioned hemiparkinsonian (HP) rat PD model. In this study, we recorded 24-hour PSG from normal and HP rats. Recordings were scored into wake, rapid eye movement (REM), and non-REM (NREM). We then examined EEG to identify REM periods and EMG to check muscle activity during REM. Normal rats showed higher wakefulness (70–80%) during the dark phase and lower wakefulness (20%) during the light phase. HP rats showed 30–50% sleep in both phases, less modulation and synchronization to the light schedule (P < 0.0001), and more long run lengths of wakefulness (P < 0.05). HP rats also had more REM epochs with muscle activity than control rats (P < 0.05). Our findings that the sleep architecture in the HP rat resembles that of PD patients demonstrate the value of this model in studying the pathophysiological basis of PD sleep disturbances and preclinical therapeutics for PD related sleep disorders including RBD.
Hsp90: a drug target?

Heat shock protein 90 (Hsp90) is a molecular chaperone involved in the trafficking of proteins in the cell. Under stressful conditions, Hsp90 stabilizes its client proteins and provides protection to the cell against cellular stressors such as in cancer cells. Disruption of Hsp90 leads to client protein degradation and often cell death. As Hsp90 has been found to be either overexpressed or constitutively more active in cancer cells, inhibitors of Hsp90 may have cancer cell selectivity. The N-terminal inhibitors, geldanamycin and radiciol, were the first two described inhibitors of Hsp90, but were not clinically useful. Subsequent analogues—17 allylamino-17demethoxygeldanamycin and 17 dimethylaminoethylamino-17-demethoxygeldanamycin—were found to be more clinically appropriate and have been studied in a number of clinical trials since 1999. In addition, to the N-terminal site of Hsp90, the C-terminal site appears to be another target for inhibition of Hsp90. More recently, inhibitors of the C terminus of Hsp90 have been developed and studied in vitro with promising results.
On detecting a trend in the residual circulation from observations of column HCl

The troposphere is the part of the atmosphere where people live. The troposphere goes up to about 12 km above the earth over places at middle latitudes like Washington, D.C. The next layer of air up in the atmosphere is called the stratosphere. The tropopause separates the troposphere and stratosphere. Most of the ozone in the atmosphere is in the stratosphere where it protects people from the harmful rays in sunlight. Near the earth s surface, ozone is a pollutant. In general, air travels from the troposphere to the stratosphere through upward motion in the tropics. Most of the air comes back down to the troposphere at middle latitudes. The so-called "stratospheric residual circulation" moves the air in the stratosphere from the tropics to the middle latitudes. In this way, the amount of air that moves out of the stratosphere into the troposphere at middle latitudes depends on the strength of the residual circulation. This overturning of the atmosphere is important as it brings chemicals produced by the activities of people into the stratosphere. Most notable are chlorofluorocarbons (CFCs) that destroy stratospheric ozone. The transport of air out of the stratosphere removes ozone-destroying chemicals, but also brings ozone into the troposphere.
Renal excretion of perfluorooctanoic acid in male rats: inhibitory effect of testosterone.

There is a marked sex difference in the whole-body elimination of perfluorooctanoic acid (PFOA) in rats, with females excreting the perfluorinated acid much more rapidly (half life [t1/2] less than 1 day) than males (t1/2 = 15 days). Our objective was to determine if androgens or estrogens are involved in causing this sex difference in PFOA elimination. Castration of males greatly increased the elimination of [1-14C]PFOA (9.4 mumol/kg, i.p.) in urine, demonstrating that a factor produced by the testis was responsible for the slow elimination of PFOA in male rats. Castration plus 17 beta-estradiol had no further effect on PFOA elimination whereas castration plus testosterone replacement at the physiologic level reduced PFOA elimination to the same level as rats with intact testes. Thus, in male rats, testosterone exerts an inhibitory effect on renal excretion of PFOA. In female rats, neither ovariectomy nor ovariectomy plus testosterone affected the PFOA urinary elimination, demonstrating that the inhibitory effect of testosterone on PFOA renal excretion is a male-specific response. Probenecid decreased the high rate of PFOA renal excretion in castrated males but had no effect on male rats with intact testes. We conclude that testosterone is a key determinant of the sex difference in PFOA elimination in rats.
Periodontal regeneration via selective cell repopulation

The purpose of this investigation was to determine the histogenesis of periodontal regeneration using the principle of selective and guided cell repopulation of the root surface. A fenestration model, developed in the squirrel monkey, made it possible to exclude gingival epithelium and connective tissue and promote cell repopulation of the denuded root surface from the periodontal ligament and alveolar bone. Experimental and sham-operated control sites were compared histometrically after 3, 7, 14 and 35 days of healing. The results indicated that new cementum, bone and periodontal ligament formation occurred by the 14th day and that regeneration of the fenestration wound was almost complete by Day 35. Root resorption and ankylosis were observed in both experimental and sham-operated controls. There was significantly more periodontal regeneration in the experimental sites, which favored cell repopulation of the root surface from the periodontal ligament and alveolar bone.
In situ neutron diffraction study of deuterated portlandite Ca(OD)2 at high pressure and temperature

The structure of deuterated portlandite, Ca(OD)2, has been investigated using time-of-flight neutron diffraction at pressures up to ∼4.5 GPa and temperatures up to ∼823 K. Rietveld analysis of the data reveals that with increasing pressure, unit-cell parameter c decreases at a rate about 4.5 times larger than that for a, which is largely due to rapid contraction of the interlayer spacing in this pressure range. Fitting of the determined cell volumes to the third-order Birch–Murnaghan equation of state yields a bulk modulus (K 0) of 32.2 ± 1.0 GPa and its first derivative (K 0′) of 4.4 ± 0.6. Moreover, on compression, hydrogen-mediated interatomic interactions within the interlayer become strengthened, as reflected by decreases in interlayer D···O and D···D distances with increasing pressure. Correspondingly, D–D, the distance between the three equivalent sites over which D is disordered, increases, suggesting a pressure-induced hydrogen disorder. This behavior is similar to that reported in brucite at elevated pressure. On heating at ∼2.1 GPa, cell parameter c increases more rapidly than a, as expected. However, because of the pressure effect, the thermal expansion coefficients, particularly along c, are much smaller than those at ambient pressure. With increasing temperature, the three partially occupied D sites become further apart, and the D-mediated interactions, mainly the interlayer D···D repulsion, become weakened.
Phase-bunching and other non-linear processes occurring in gyroresonant wave-particle interactions

Consideration of the movement of individual electrons in a magnetized plasma in which a monochromatic wave is propagating in the whistler mode. Simple expressions are derived which give the displacement of the electrons as a function of time, the phase angle that their velocity vector makes with the magnetic component of the wave, their pitch angle, and energy changes. A useful formula is obtained which gives the velocity range over which particles remain trapped inside the wave, as a function of the wave intensity and of the initial phase angle of the particle. It is shown that even strictly resonant particles can escape from the wave when their initial phase angle is very small. From the derived expressions, it is possible to compute the phase-bunching effect which occurs approximately at one trapping wavelength behind the leading edge of the interaction region.
The Threshold Effect of Platform Width: A Reply to Davis and Shea

This paper is a reply to Davis & Shea's experimental test of Dibble & Pelcin's method for reconstructing original flake mass. Davis & Shea found that the equation for predicting the original flake mass of plate glass flakes presented by Dibble & Pelcin underestimates the original flake mass of obsidian flakes produced by a modern flintknapper. They hypothesize that the accuracy of estimating original flake mass would be improved with the addition of platform width to the equation. The purpose of this reply is to discuss why platform width, a threshold variable, does not aid in the estimation of original flake mass and how original flake mass can be accurately modelled using only theoretical platform thickness and exterior platform angle.
The on-line computer system for determining the systolic time intervals

Abstract A description is presented of a method for obtaining systolic time intervals on an on-line computer system. Following the collection of data a summary of the average of the time intervals is presented at the teletype including the standard deviation along with the predicted values for the heart rate. The entire recording procedure usually takes between five and ten minutes, using an experienced operator at the teletype.