cssi/SciSciGPT-SciSciNet huggingface dataset:
Mental health consequences of COVID-19: a nationally representative cross-sectional study of pandemic-related stressors and anxiety disorders in the USA.

Objective To document the prevalence of anxiety disorders in the USA during the COVID-19 pandemic. Design A cross-sectional analysis. Setting A nationally representative sample in the USA between 31 March and 13 April 2020. Participants 1450 English-speaking adult participants in the AmeriSpeak Panel. AmeriSpeak is a probability-based panel designed to be representative of households in the USA. Main outcome measures Prevalence of probable generalised anxiety disorder (GAD) using the GAD-7 and post-traumatic stress symptoms (PTSS) using the four-item PTSD (post-traumatic stress disorder) checklist. Both outcomes were stratified by demographics and COVID-19-related stressors. Results The majority of participants were female (51.8%), non-Hispanic white (62.9%) and reported a household saving of $5000 or more. Those between 18 and 29 years old were the largest age group (38.1%) compared with 40–59 years (32.0%) and 60 years or more (29.9%). The prevalence of probable GAD was 10.9% (95% CI 9.1% to 13.2%) and the prevalence of PTSS was 21.7% (95% CI 19.1% to 24.6%). Among participants reporting five or more COVID-19-related stressors, the prevalence of probable GAD was 20.5% (95% CI 16.1% to 25.8%) and the prevalence of PTSS was 35.7% (95% CI 30.2% to 41.6%). Experiencing five or more COVID-19-related stressors was a predictor of both probable GAD (OR=4.5, 95% CI 2.3 to 8.8) and PTSS (OR=3.3, 95% CI 2.1 to 5.1). Conclusions The prevalence of probable anxiety disorders in the USA, as the COVID-19 pandemic and policies implemented to tackle it unfolded, is higher than estimates reported prior to the pandemic and estimates reported following other mass traumatic events. Exposure to COVID-19-related stressors is associated with higher prevalence of both probable GAD and PTSS, highlighting the role these stressors play in increasing the risk of developing anxiety disorders in the USA. Mitigation and recovery policies should take into account the mental health toll the pandemic had on the USA population.
Visions of Middle School: How Beginning Teacher Candidates Describe their Early Visions for Teaching

The purpose of this research was to explore how beginning middle school teacher candidates describe their emerging visions for teaching. This collective case study of one cohort of teacher candidat...
WHAT NOT TO WEAR: FASHION AND FEMALE CANDIDATES IN OKLAHOMA

What impact does a female candidate's clothes have on her ability to be elected to office? This controlled experiment draws on candidate image research to compare the same political candidate's chances of getting elected when she assumes three different personas: Powerful, Traditional, and Sexy. When running our experiment on students at East Central University (N=95), we reveal that "voters" prefer the Powerful candidate, although they attribute more favorable characteristics to the Traditional candidate. We applied the results of our experiment to the 2010 gubernatorial election between Jari Askins and Mary Fallin to conclude that in combining the Powerful and Traditional personas, Mary Fallin developed a very effective image.
Inhibition of AKT abrogates chemotherapy- induced NF-κB survival mechanisms: implications for therapy in pancreatic cancer

Abstract Background When activated, the nuclear factor (NF)-κB pathway is a potent cellular signal that inhibits apoptotic cell death. Pancreatic cancer is resistant to the apoptotic effect of chemotherapy, though it is unclear whether this is an inherent feature or a survival signal engaged in response to chemotherapy. We investigated whether pancreatic cancer cells activate the NF-κB pathway in response to chemotherapy and whether inhibition of this response altered the apoptotic efficacy of chemotherapy. Study design We determined NF-κB activity after chemotherapy treatment of the MIA-PaCa-2 human pancreatic cancer cell line using both physical (electrophoretic mobility shift assay) and functional (luciferase) techniques. The effect of chemotherapy on transcription of the antiapoptotic gene BCL-2, a target of NF-κB, was determined. We examined the effect of inhibition of Akt, an upstream activator of NF-κB, on the molecular (NF-κB function and BCL-2 transcription) and cellular (apoptosis) effect of chemotherapy. Results Both the chemotherapeutic agents gemcitabine and paclitaxel activated NF-κB and stimulated BCL-2 gene promoter activity. The stimulation of BCL-2 promoter function was directly regulated by NF-κB. These cellular responses were blocked by inhibition of Akt. The apoptotic effect of gemcitabine and paclitaxel also was enhanced after Akt inhibition. Conclusions Part of the apoptotic resistance of pancreatic cancer may be mediated by activation of the NF-κB survival pathway in response to chemotherapy. Inhibition of this response may be an important adjunct to increase the efficacy of chemotherapy.
Assessing evidence, arguments, and inequality in Bedford v. Canada

Until recently, Canada criminalized anyone who lived "wholly or in part on the avails of prostitution of another person,” and anyone who kept, controlled, or knowingly permitted a “bawdy-house” for ...
Saliency-maximized audio visualization and efficient audio-visual browsing for faster-than-real-time human acoustic event detection

Browsing large audio archives is challenging because of the limitations of human audition and attention. However, this task becomes easier with a suitable visualization of the audio signal, such as a spectrogram transformed to make unusual audio events salient. This transformation maximizes the mutual information between an isolated event's spectrogram and an estimate of how salient the event appears in its surrounding context. When such spectrograms are computed and displayed with fluid zooming over many temporal orders of magnitude, sparse events in long audio recordings can be detected more quickly and more easily. In particular, in a 1/10-real-time acoustic event detection task, subjects who were shown saliency-maximized rather than conventional spectrograms performed significantly better. Saliency maximization also improves the mutual information between the ground truth of nonbackground sounds and visual saliency, more than other common enhancements to visualization.
Factors associated with contralateral preventive mastectomy

Introduction Contralateral prophylactic mastectomy (CPM) is an option for women who wish to reduce their risk of breast cancer or its local recurrence. There is limited data on demographic differences among patients who choose to undergo this procedure.
Responses of mental stress–induced myocardial ischemia to escitalopram treatment: Background, design, and method for the Responses of Mental Stress Induced Myocardial Ischemia to Escitalopram Treatment trial

Background Mental stress–induced myocardial ischemia (MSIMI) is common in patients with clinically stable coronary heart disease (CHD) and is associated with poor outcomes. Depression is a risk factor of MSIMI. The REMIT trial investigates whether selective serotonin reuptake inhibitor (SSRI) treatment can improve MSIMI. The rationale and outline of the study are described. Method In this single-center randomized clinical trial, adult patients with clinically stable CHD are recruited for baseline mental and exercise stress testing assessed by echocardiography. In addition, psychometric questionnaires are administered, and blood samples are collected for platelet activity analysis. Patients who demonstrate MSIMI, defined by new abnormal wall motion, ejection fraction reduction ≥8%, and/or development of ischemic ST change in electrocardiogram during mental stress testing, are randomized at a 1:1 ratio to escitalopram or placebo for 6 weeks. Approximately 120 patients with MSIMI are enrolled in the trial. The stress testing, platelet activity assessment, and psychometric questionnaires are repeated at the end of the 6-week intervention. The hypothesis of the study is that SSRI treatment improves MSIMI via mood regulation and modification of platelet activity. Conclusion The REMIT study examines the effect of SSRI on MSIMI in vulnerable patients with CHD and probes some potential underlying mechanisms.
Uranium and microcracks in a 1,000-meter core, Redstone, New Hampshire

The spatial distribution and mineralogical association of uranium in 30 samples of a 1,000 meter core from the Redstone (NH) Quarry were examined with fission track techniques, backscattered electron imaging, and energy dispersive X-ray spectrometry with the following results for the Conway and Mount Osceola granites: (1) Uranium occurs in microcracks sealed with siderite and/or with Ca+ RE fluorocarbonate minerals; the uranium contents of siderite and the RE fluorocarbonates are 1 to 30 ppm and 500–1,500 ppm, respectively. (2) Siderite and to a lesser extent RE fluorocarbonate minerals occur as replacement minerals of amphibole and biotite; the RE fluorocarbonates are the main alteration minerals of allanite. (3) The degree of alteration and the extent of uranium redistribution are greater in samples with major uraniferous microcracks. (4) The contents of Ca and Mn are approximately constant for siderite in sealed cracks throughout the Conway and Mount Osceola granites for the entire section penetrated by the corehole, approximately 700 meters. — From these observations, we conclude that an extensive set of fractures throughout a significant volume of the Mount Osceola and Conway granties were the conduits through which hydrothermal fluids containing CO2, uranium, and REs circulated. Microcracks facilitated fluid-rock interactions resulting in alteration and uranium redistribution. Certain primary uraniferous accessory minerals, i.e., allanite and ilmenorutile may have been the source for at least part of the uranium and REs that now occur in secondary minerals in these granites.
A role for collagen XXIII in cancer cell adhesion, anchorage-independence and metastasis

Collagen XXIII is a transmembrane collagen previously shown to be upregulated in metastatic prostate cancer that has been used as a tissue and fluid biomarker for non-small cell lung cancer and prostate cancer. To determine whether collagen XXIII facilitates cancer cell metastasis in vivo and to establish a function for collagen XXIII in cancer progression, collagen XXIII knockdown cells were examined for alterations in in vivo metastasis as well as in vitro cell adhesion. In experimental and spontaneous xenograft models of metastasis, H460 cells expressing collagen XXIII shRNA formed fewer lung metastases than control cells. Loss of collagen XXIII in H460 cells also impaired cell adhesion, anchorage-independent growth and cell seeding to the lung, but did not affect cell proliferation. Corroborating a role for collagen XXIII in cell adhesion, overexpression of collagen XXIII in H1299 cells, which do not express endogenous collagen XXIII, enhanced cell adhesion. Consequent reduction in OB-cadherin, alpha-catenin, gamma-catenin, beta-catenin, vimentin and galectin-3 protein expression was also observed in response to loss of collagen XXIII. This study suggests a potential role for collagen XXIII in mediating metastasis by facilitating cell–cell and cell–matrix adhesion as well as anchorage-independent cell growth.
The reaction of O(1D) with H2O and the reaction of OH with C3H6

The N2O was photolyzed at 2139 A to produce O(1 D) atoms in the presence of H2O and CO. The O(1 D) atoms react with H2O to produce HO radicals, as measured by CO2 production from the reaction of OH with CO. The relative rate constant for O(1 D) removal by H2O compared to that by N2O is 2.1. In the presence of C3H6, the OH can be removed by reaction with either CO or C3H6.
Co-purification of 130 kD nitric oxide synthase and a 22 kD link protein from human neutrophils.

Abstract The synthesis of nitric oxide (NO) from L-arginine has been demonstrated in several cell types. Both constitutive and inducible forms of NO synthase have been described in different cells. We purified the constitutive form of NO synthase enzyme in human neutrophils using a two-column procedure. Crude 100,000g supernatant of human neutrophils was passed through a 2′-5′-ADP-agarose column followed by a DEAE-Bio-Gel A anion exchange column. NO synthase enzyme migrated as a single band (MW ≈ 130,000) on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Its activity was dependent upon nicotinamide adenine dinucleotide phosphate (NADPH) and (6R)-tetrahydro-L-biopterin (BH4). In addition, flavin adenine dinucleotide (FAD) was also found to be essential for its maximal activity. A second NADPH, FAD-dependent component (MW ≈ 22kD) was also found consistently on the SDS-PAGE gel. These observations suggest co-regulation between NO synthase enzyme and this NADPH, FAD-dependent component, which may be associated with the superoxide radical generating system.
Waves and Sandbar Erosion in the Grand Canyon: Applying Coastal Theory to a Fluvial System

Abstract Progressive erosion of channel-bank sandbars in Grand Canyon has long been thought to be associated with emplacement and operation of Glen Canyon Dam, although the specific physical mechanisms causing local erosion are poorly understood. A short-term study (order of days) of detailed flow patterns and morphologic adjustments at Stone Creek and Fern Glen sandbars during constant discharge demonstrates that surface-gravity waves and other quasi-periodic flow oscillations are important to the stability characteristics of these alluvial deposits. The primary role of waves is to agitate bottom sediments, entraining them on an intermittent basis. Mean currents associated with recirculating eddies (ordinarily of insufficient strength to entrain sediments) act, in the presence of waves, as a net background drift able to transport sediments away from the bar face and into the main channel. Thus combined wave-current interactions provide for sediment transport possibilities that might not occur in the abse...
Determining the hospital trauma financial impact in a statewide trauma system

Background There have been no comprehensive studies across an organized statewide trauma system using a standardized method to determine cost. Study Design Trauma financial impact includes the following costs: verification, response, and patient care cost (PCC). We conducted a survey of participating trauma centers (TCs) for federal fiscal year 2012, including separate accounting for verification and response costs. Patient care cost was merged with their trauma registry data. Seventy-five percent of the 2012 state trauma registry had data submitted. Each TC's reasonable cost from the Medicare Cost Report was adjusted to remove embedded costs for response and verification. Cost-to-charge ratios were used to give uniform PCC across the state. Results Median (mean ± SD) costs per patient for TC response and verification for Level I and II centers were $1,689 ($1,492 ± $647) and $450 ($636 ± $431) for Level III and IV centers. Patient care cost–median (mean ± SD) costs for patients with a length of stay >2 days rose with increasing Injury Severity Score (ISS): ISS Conclusions Patient care cost rose with increasing ISS, length of stay, ICU days, and ventilator days for patients with length of stay >2 days and ISS 9+. Level I centers had the highest mean ISS, length of stay, ICU days, and ventilator days, along with the highest PCC. Lesser trauma accounted for lower charges, payments, and PCC for Level II, III, and IV TCs, and the margin was variable. Verification and response costs per patient were highest for Level I and II TCs.
Chemical modification of canavanine with p-nitrophenylglyoxal. Factors influencing the chemistry and reactivity of α-dicarbonyl-guanidino reactions

The role of structural features and deprotonation of guanidino derivatives on chemical reactions with p-nitrophenylglyoxal has been investigated. Canavanine, an arginine analog, reacts to form a yellow product, which absorbs maximally at 350 nm (epsilon = 6500) and at 278 nm (epsilon = 14 500). Elemental analysis, fast atom bombardment mass spectral analysis, n.m.r. and i.r. studies suggest that the product is a 5-(p-nitrophenyl)4-oxo-2 imidazoline derivative of canalaline. Kinetic studies show that the second order rate constant for the reaction increases with increasing pH in the range of pH 7-11.0. It is concluded that the pH dependence of the reaction can be explained by general base catalysis and not simply by a deprotonation of the guanidinoxy side chain. The reaction of arginine, polyarginine, and other derivatives differs markedly from that of canavanine. The results suggest that change in the tautomeric equilibria between the imino and amino forms of the guanidino group may partly account for differences in reaction of canavanine and arginine and the reactions of specific arginyl residues in proteins.
Mobile agent connection establishment and management (CEMA): message exchange for pervasive computing environments

Pervasive computing is an emerging technology that offers new possibilities to distributed computing and computer networking; it employs a wide variety of smart, ubiquitous devices throughout an individual's working and living environment. Mobile agents are software entities that can migrate between servers (mobile agent environments) of the network accomplishing various tasks on the behalf of their owners. The objective of this paper is to describe a test and prototyping environment for experimenting with mobile agents in pervasive environments. A prototype environment for a novel, proactive infrastructure is described for mobile agent assisted pervasive computing. In addition, a new message passing algorithm is provided for mobile agent connection establishment and management (CEMA). Simulation results show the performance of the proposed approach.
A cruciform-dumbbell model for inverted dimer formation mediated by inverted repeats

Small inverted repeats (small palindromes) on plasmids have been shown to mediate a recombinational rearrangement event in Escherichia coli leading to the formation of inverted dimers (giant palindromes). This recombinational rearrangement event is efficient and independent of RecA and RecBCD. In this report, we propose a cruciform-dumbbell model to explain the inverted dimer formation mediated by inverted repeats. In this model, the inverted repeats promote the formation of a DNA cruciform which is processed by an endonuclease into a linear DNA with two hairpin loops at its ends. Upon DNA replication, this linear dumbbell-like DNA is then converted to the inverted dimer. In support of this model, linear dumbbell DNA molecules with unidirectional origin of DNA replication (ColE1 ori ) have been constructed and shown to transform E.coli efficiently resulting in the formation of the inverted dimer. The ability of linear dumbbell DNA to transform E.coli suggests that the terminal loops may be important in bypassing the requirement of DNA supercoiling for initiation of replication of the ColE1 ori.
Dud, A Derivative-Free Algorithm for Nonlinear Least Squares

Derivative-free nonlinear least squares algorithms which make efficient use of function evaluations are important for fitting models defined by systems of nonlinear differential equations. A new Gauss-Newton-like algorithm with these properties is developed. The performance of the new algorithm (called Dud for “doesn't use derivatives”) is evaluated on a number of standard test problems from the literature. On these problems Dud competes favorably with even the best derivative-based algorithms.
Welfare, Value, Empire

(2002). Welfare, Value, Empire. Emergences: Journal for the Study of Media & Composite Cultures: Vol. 12, No. 2, pp. 273-284.
Endogenous trade policy under foreign direct investment

Abstract Using Bernheim and Whinston (1986) common agency game, we endogenize trade policy in a duopoly composed of a domestic firm and a foreign firm, where both firms influence the domestic government's trade policy via their contributions. The foreign firm can jump over trade restrictions by undertaking foreign direct investment (FDI) in the domestic market. The government prefers a voluntary export restraint (VER) to a tariff for two reasons. First, a VER leads to higher contributions from the foreign firm than a tariff. Second, a VER provides a higher level of protection to the domestic firm without generating FDI by the foreign firm.
The rise and fall of psi in physics at MIT

Small‐scale trials of the Personalized System of Instruction (PSI) in physics at MIT under the sponsorship of the Education Research Center were followed by adoption of large‐scale introductory PSI courses in the Department of Physics. After four semesters, all introductory physics PSI courses were suspended. This study investigates what happened. We point out organizational difficulties in going from small‐ to large‐scale use of the PSI method. We also identify certain conflicting perceptions among participants and observers that contributed to the suspension. The study, we hope, is an example of an informative ’’postmortem’’ of a type much needed in higher education.
Comparison of pod-wall characteristics with seed damage and resistance to the alfalfa seed chalcid (Hymenoptera : eurytomidae) in Medicago species

The alfalfa seed chalcid, Bruchophagus roddi (Gussakovsky), is the most destructive insect to alfalfa, Medicago sativa L., seed. Because chemicals are ineffective in its control, plant resistance offers the most viable method of reducing seed losses. The objective of our study was to compare pod-wall characteristics with seed damage and resistance to the alfalfa seed chalcid in eight Medicago species and three interspecific hybrids. The percentage of chalcid-damaged seed, based on seed numbers, averaged 0.0% for annual species, 18.4% for perennial glandular-haired species, and 20.4% for perennial control cultivars. The percentage of other seed losses averaged 8.4% for perennial control cultivars, 21.3% for annual species, and 35.5% for perennial glandular-haired species. Pod-wall thickness averaged: perennial glandular-haired species, 131.9μm; annual species, 139.4μm; and perennial control cultivars, 144.0 μm. Increased pod-wall thickness reduced other seed losses not attributed to the chalcid. Phenotypic variation in pod-wall thickness suggests that selection for this trait should be effective, assuming there is significant heritable variation. Our findings suggest also that pod-wall lignification may reduce seed losses due to chalcid damage. The highest levels of resistance to the alfalfa seed chalcid were found in the annual species, which also had highly lignified pod-walls. The annual species, however, are cross-incompatible with M. sativa . Thus, breeding for increased pod-wall lignification may reduce seed losses due to damage by the chalcid, if the mechanisms that control lignin production and accumulation are heritable and in cross-compatible Medicago genotypes.
Engineering design principles for organelle size control systems

Organelle size is an important determinant of organelle function, and for this reason cells have evolved mechanisms to control and adjust organelle size in the face of intrinsic biological fluctuations. Size control systems have been found that employ a variety of distinct mechanisms, which fall into a small number of classes. Each class represents a design principle by which artificial size controllers could be developed for synthetic biology applications.
Do Endangered Razorback Suckers Have Poor Larval Escape Performance Relative to Introduced Rainbow Trout

Abstract Poor recruitment has generated the hypothesis that the endangered razorback sucker Xyrauchen texanus is particularly vulnerable to predation early in its life history. We compared the escape responses of razorback suckers, which are adapted to the historically warm waters of the Colorado River, with those of rainbow trout Oncorhynchus mykiss, an introduced coldwater species, throughout early development at water temperatures of 12°C and 18°C. We quantified escape performance using maximum velocity, acceleration, and time to maximum velocity and acceleration. Both species showed complete temperature compensation for escape performance; individuals reared at 12°C performed as well as those reared at 18°C. Performance was also similar between species, although two variables exhibited a species × size interaction. Small razorback suckers were faster (greater maximum velocity and acceleration) than small rainbow trout, while large larvae performed similarly. We also determined that razorback sucker la...
Linearity and Resolution of Photodiodes

Measurements are reported of the resolution and linearity of Hamamatsu S1337 Photodiodes mounted on a NaI crystal and exposed to electron energy deposits of up to 80 GeV. The results indicate that these diodes can replace photomultipliers in high-light-yield detectors such as NaI and BGO, when operated in multi-element, compact assemblies in the presence of a magnetic field.
Evolution of regulatory elements producing a conserved gene expression pattern in Caenorhabditis.

Summary Natural selection acts at the level of function, not at the logistical level of how organisms achieve a particular function. Consequently, significant DNA sequence and regulatory differences can achieve the same function, such as a particular gene expression pattern. To investigate how regulatory features underlying a conserved function can evolve, we compared the regulation of a conserved gene expression pattern in the related species Caenorhabditis elegans and C. briggsae. We find that both C. elegans and C. briggsae express the ovo-related zinc finger gene lin-48 in the same pattern in hindgut cells. However, the regulation of this gene by the Pax-2/5/8 protein EGL-38 differs in two important ways. First, specific differences in the regulatory sequences of lin-48 result in the presence of two redundant EGL-38 response elements in C. elegans, whereas the redundancy is absent in C. briggsae. Second, there is a single egl-38 gene in C. briggsae. In contrast, the gene is duplicated in C. elegans, with only one copy retaining the ability to regulate lin-48 in vivo. These results illustrate molecular changes that can occur despite maintenance of conserved gene function in different species.
Studies on nuclei of Paramecium aurelia. I. Isolation and purification by continuous or discontinuous sucrose gradient centrifugation and biochemical composition.

SYNOPSIS. Nuclei of Paramecium aurelia were isolated and purified by a new method involving the use of continuous or discontinuous sucrose gradient centrifugation. As judged from the DNA levels or nuclear counts in the purified samples, 21–22% of the nuclei were recovered by this method. The single density of the nuclei estimated on the basis of linear sucrose gradients was between 1.35 ± 0.01 and 1.36 ± 0.01. The average picogram quantities of total protein, DNA, and RNA per nucleus were 435, 62.2, and 51.2, respectively.
Total electron impact ionization cross sections of K shells of surface atoms

Abstract Measurements of total K-shell, electron impact ionization cross sections of C, N, O, and Na adsorbed in single adlayers on W (100) are obtained from the Auger electron intensities. The observed cross sections are compared with the Burhop, flrst-Born approximation theory and with the Rudge-Schwartz, Coulomb-Born theory. The Coulomb-Born theory, which includes effects of Coulomb forces from the nucleus, agrees best with measured cross sections as a function of primary energy. Corrections due to secondary excitation are computed, showing that its relative contribution is as much as 25 % for C in the energy range studied.
Destabilization of a 650 km chemical boundary layer and its bearing on the evolution of the continental crust

A mechanism for the production of a chemical change in the mantle, from primordial silicate compositions above the 650 km discontinuity to differentiated compositions below, is reviewed. Some consequences of this are the stabilization of two layer convection with a temperature contrast between the anhydrous mantle solidus and the geotherm which, at 650 km depth, is lower than any other location in the mantle. With thermal contributions from the concentration of the heat producing elements U, Th and K below the 650 km mantle boundary layer and the higher geotherms in the past, widespread or catastrophic melting may have taken place at this location. An episodic breach of this boundary layer by extensive heat and mass transport may have periodically destroyed any simple two-layer convection geometry in the mantle. Such episodic injections of mass and energy into the upper mantle from below may have been the mechanism responsible for episodes of enhanced surface tectonism and thermal activity which appear to be recorded in apparent polar wandering paths and radiometric ages of continental rocks.
Brain histology and behavior of mice injected with urease.

Mice were injected with crystalline jackbean urease in dosages of 0.4 units of enzyme activity per mouse at 0 and 12 hrs. One group was killed by decapitation at 24 hrs for analysis of brain DNA, RNA and blood ammonia. Stomach contents and rectal temperature were determined on similarly treated animals. Histological examinations of brain tissue obtained at 30–38 hr after initial injection showed increases in size and number of astrocytic nuclei and the astrocytes were typical in appearance of Alzheimer Type II cells. In the most severe cases there was spongy vacuolation of the neuropil. Mice showing these histological changes showed behavior which ranged from a small observable change to coma or coma with generalized convulsive seizures. About one half of the animals survived coma, but all showing convulsive seizures died. All animals showing behavior changes demonstrated significantly higher blood ammonia concentrations than those not showing behavior changes. The urease injected animals did not show a statistically significant reduction in brain DNA and RNA. Mice injected with an LD50 of urease (55 units/kg body wt) developed signs of intoxication earlier and the cellular changes in their nervous tissue were seen earlier than in animals injected twice with 0.4 units of urease. Gastric retention and hypothermia were observed in urease injected animals.
The growth of (Al,Ga)Sb tilted superlattices and their heteroepitaxy with InAs to form corrugated-barrier quantum wells

Abstract We have demonstrated the molecular beam epitaxial growth of (Al,Ga)Sb tilted superlattices (TSLs) on 2° vicinal (100) GaSb and GaAs substrates. The existence of (Al,Ga)Sb TSLs proves that step-flow growth can occur in this material system, and in the presence of strain. Lateral fluctuations in the tilt angle of the superlattice are observed and are found to be caused by a non-uniform distribution of incorporated adatoms which is correlated with the surface step density. The (Al,Ga)Sb TSL growth was also combined with InAs growth to form an InAs quantum well with “corrugated” barriers consisting of (Al,Ga)Sb TSLs. The electron mobilities in this structure exceeded 6×105 cm2/V⋯s.
Evaluation of dosage-release formulations on inhibition of drug clearance: effect of sustained- and immediate-release verapamil on propranolol pharmacokinetic parameters.

Limited information exists regarding the influence of dosage-release formulation on inhibition of drug metabolism. Therefore, the purpose of this study was to evaluate the effect of immediate-release (IR) and sustained-release (SR) verapamil on the pharmacokinetic parameters of propranolol in 12 healthy men. IR propranolol, 160 mg, was administered alone (Phase A) and following either IR verapamil, 80 mg t.i.d., (Phase B) or SR verapamil, 240 mg q.d., (Phase C) in a randomized crossover fashion. Of the 12 subjects enrolled, only seven were able to be analyzed secondary to assay interference. Oral clearances for L-propranolol for Phases A, B, and C were 198 +/- 70, 156 +/- 76, and 143 +/- 85 L/h, respectively. Oral clearances for D-propranolol for Phases A, B, and C were 203 +/- 96, 172 +/- 96, and 152 +/- 102 L/h, respectively. No significant differences were observed. However, when the verapamil groups (Phase B and C) were combined and compared to Phase A, a significant decrease in clearance for propranolol isomers was observed. In conclusion, due to the unexpected low numbers of patients evaluated, no significant differences in oral clearance were observed among the three treatment phases. However, there is a trend suggesting that SR verapamil had the greatest effect on propranolol clearance, which may warrant caution when changing from one formulation to another.
MHV Infection of the CNS: Mechanisms of Immune-Mediated Control

Mice infected with neurotropic strains of mouse hepatitis virus (MHV) clear infectious virus; nevertheless, viral persistence in the central nervous system (CNS) is associated with ongoing primary demyelination. Acute infection induces a potent regional CD8+ T-cell response. The high prevalence of virus specific T cells correlates with ex vivo cytolytic activity, interferon-gamma (IFN-γ) secretion and efficient reduction in virus. Viral clearance from most cell types is controlled by a perforin dependent mechanism. However, IFN-γ is essential for controlling virus replication in oligodendrocytes. Furthermore, CD4+ T cells enhance CD8+ T-cell survival and effectiveness. Clearance of infectious virus is associated with a gradual decline of CNS T cells; nevertheless, activated T cells are retained within the CNS. The loss of cytolytic activity, but retention of IFN-γ secretion during viral clearance suggests stringent regulation of CD8+ T-cell effector function, possibly as a means to minimize CNS damage. Ho...
In situ high-resolution electron microscopy reactions in semiconductors

Abstract An assessment has been made of the feasibility of performing in situ electron microscopy experiments, under high-resolution imaging conditions at high temperature. The particular field of interest is that of interface reactions in semiconductor systems. It is found that the image quality is sufficiently good, especially with new medium-voltage instruments, that changes in the specimens can be followed for extensive periods of time. Results on the solid phase epitaxial regrowth of silicon compare well with those obtained from high-voltage electron microscopy and Rutherford backscattering spectroscopy studies on the same materials. The behavior of some metal-gallium arsenide reactions (specifically TiGaAs and NiGaAs) has also been investigated. The influence of extremely thin foils is unpredictable at present.
Bronchoscopy simulation: a brief review.

More than 500,000 flexible bronchoscopies are performed annually by chest physicians in the United States (Ernst et al., Chest 123:1693–1717, 2003). Indications include diagnosis of lung cancer and airway tumors, benign strictures, pulmonary infections, and treatment of central airway obstruction, emphysema, and intraepithelial lesions such as carcinoma in-situ. Anesthesiologists, cardiothoracic and trauma surgeons, otolaryngologists, and critical are physicians also perform this procedure as part of difficult airway management, intubation or airway inspection and bronchial toilet. Compared to the expanding body of simulation-related literature that is available in other procedural fields, however, the volume of published work relating to bronchoscopy is scant. The purpose of this paper is to provide an overview of the available literature pertaining to the use of simulation in bronchoscopy education, and to demonstrate how this limited yet valuable body of work lays a foundation for the future use of simulator-based bronchoscopy training.
Risk-adjusted control charts for health care assessment

The recent Joint Commission on Accreditation of Healthcare Organization (JCAHO) requirement that hospital accreditation be based upon a Total Quality Management (TQM) approach has focused the attention of health care administrations on the use of techniques such as control charts. However, control charts are not typically adjusted for severity of illness. This adjustment is needed because, unlike industrial organizations, hospitals are not able to control all of their inputs and must accept variances in their patients. In this paper, we present a methodology for adjusting a health care organization's control charts to reflect their patient population's severity of illness during different time intervals. We then demonstrate that risk-adjusting expected patient outcomes can change our assessments of the relative quality of care offered by a health care organization in different time periods.
On multiplication in algebraic extension fields

In this paper we characterize all algorithms for obtaining the coefficients of (Σn−1i=0 xiui)(Σn−1i=0 yiui) mod P(u), where P(u) is an irreducible po lynomial of degree n, which use 2n − 1 multiplications. It is shown that up to equivalence, all such algorithms are obtainable by first obtaining the coefficients of the product of two polynomials, and then reducing modulo the irreducible polynomial.
Development of student-teacher relationships in rural early elementary classrooms

Abstract An increasing body of literature documents associations between student–teacher relationships, children’s academic success, and children’s social competence in school. Less is known about characteristics and processes involved in the quality of relationships between students and teachers, and little research has examined these issues with populations of young students and teachers living in rural communities. The current study examined the relationships between rural kindergarten and first-grade students and their teachers in spring of the school year, predicted by child demographic factors, child process factors, and teacher characteristics. Using a multi-level model to account for clustering of children in classrooms, children’s behavior and literacy skills were examined as contributors to the teachers’ perceptions of the developing teacher–student relationship, focusing on their potential to mediate associations between more distal characteristics and teacher–student relationships. Controlling for relationship conflict in fall, boys and African American students were more likely to have relationships with teachers that were higher in conflict in spring. When behavior and literacy skills measures were added to the model, children’s behavior mediated the effect of gender, such that behavior problems accounted for much of the variance in student–teacher conflict associated with gender. However, neither behavior problems nor literacy skills mediated the effects of minority status on conflict; African American students had poorer relationships with teachers regardless of behavior or literacy skills.
Subjective Ratings of Accessibility Using Full-Scale Bathroom Environments

Full-scale modeling was used to assess subjective ratings of difficulty for the bathroom environment across four different configurations. Two configurations complied with nationally accepted accessibility standards. One exceeded the standards, representing a “universal design”; the other was representative of a common yet unsupportive design. Participants simulated activities of daily living and offered subjective ratings of each design in general, and for each sub-area (e.g. toilet, shower, lavatory) for each design. Results demonstrate subjective differences between bathroom configurations. The interaction between humans and the built environment should include a host of diagnostic tools complete with subjective assessments.
Robust damage localization algorithm for highway plate-girder bridges

In this paper, a robust algorithm to detect and localize damage in full-scale plate-girder bridges by utilizing modal response parameters of undamaged (as-built) and damaged structures is presented. In the first part, a damage detection algorithm which yields information on the location of damage directly from changes in mode shapes of structures is outlined. In the next part, the algorithm is implemented to detect and localize damage in a real highway bridge (on the US Highway I-40) located in Bernalillo County, New Mexico, USA. In this damage detection exercise, pre-damage and post-damage modal parameters of only a single mode measured from the test structure are utilized to localize the damage.
Variability, Seasonality, and Persistence of Fecal Coliform Bacteria in a Cold-Region, Urban Stream

Fecal coliform FC analyses were conducted on weekly water samples collected from a single watershed over a 2-year period in Anchorage, Alaska. Although peak FC concentrations 100 FC/100 mL were observed primarily during the warmer months, lower FC levels 20 FC/100 mL could be observed throughout the year in the urbanized portion of the watershed. Me- dian annual FC counts ranged from 3 FC/100 mL at an undeveloped site to 49 FC/100 mL at one of the urbanized sites. Median FC concentrations were found to be significantly higher in the summer compared to the winter at two locations directly downstream from a lake p=0.011 and 0.029, but not at the sites up- stream or distant from the lake. FC-discharge relationships indicated a significant negative correlation between FC concentration and discharge at two sites p =0.030 and 0.035 and no significant correlation at the remaining three sites. In total, the results indicated that the water quality was impacted not only by peak
Bayesian PET image reconstruction incorporating anato-functional joint entropy

We developed a maximum a posterior (MAP) reconstruction method for PET image reconstruction incorporating MR image information, with the joint entropy between the PET and MR image features serving as the prior. A non-parametric method was used to estimate the joint probability density (JPD) of the PET and MR images. The sampling rate for Parzen window estimation of the JPD was studied for both simulated phantom and clinical FDG PET brain images. Using realistic simulated PET and MR brain phantoms, the quantitative performance of the proposed algorithm was investigated. In particular, variations in the weighting factor on the MAP prior as well as the variance in the Parzen window were examined. Incorporation of the anatomical information via this technique was seen to noticeably improve the noise vs. bias tradeoff in various regions of interest.
Is Intersonic Dislocation Motion Possible? Singularity Analysis for an Edge Dislocation Accelerating through the Shear Wave Speed Barrier

The analysis of Markenscoff and Clifton (J Mech Phys Solids 29:253–262, 1981) for a generally nonuniformly moving Volterra edge dislocation, valid both for subsonic and intersonic/supersonic motion, is focused on the instant in which the dislocation accelerates through the shear-wave speed barrier. Mathematically, the roots (of the argument of the step function $$f\left( \xi \right) = t - \eta \left( \xi \right) - rb$$ that defines the intervals of the path of the motion that contribute to the field point) change from a pair of complex conjugate to a double real, splitting into two real ones, and, at the instant of the transition to intersonic motion, the stress analysis is performed at this double root maximum of $$f\left( \xi \right)$$ . The stress at the forming Mach front contains a $$\frac{{\log \left| {\xi - \xi ^* } \right|}}{{\left| {\xi - \xi ^* } \right|^{\tfrac{1}{2}} }}$$ singularity in the coefficient of the delta function, which can be removed by a ramp-core (delta sequence rather than delta function) model of the core displacement.
Streptokinase-induced, antibody-mediated platelet aggregation: A potential cause of clot propagation in vivo

The administration of intracoronary streptokinase to a patient with a prior history of rheumatic fever was associated with the retrograde propagation of thrombus from the left anterior descending coronary artery into the left main coronary artery with near catastrophic consequences. The addition of streptokinase to platelet-rich plasma from the patient initiated platelet aggregation and secretion in vitro. Platelet aggregation was also seen in 1 of 15 control subjects after the addition of streptokinase, and the addition of plasma or immunoglobulin G (IgG) from the index patient supported platelet aggregation in the presence of streptokinase in all of the previously nonreactive control subjects. This in vitro platelet aggregation was specific for streptokinase and not initiated by either urokinase or tissue plasminogen activator. Streptokinase-induced platelet aggregation was not inhibited by aprotinin, but was completely attenuated by the addition of an excess of antihuman IgG Fab. These findings suggest that streptokinase can initiate specific antibody-mediated platelet aggregation in vitro and may be more than coincidentally related to clot propagation or thromboembolism in vivo.
Effects of electrical stimulation and electrocoagulation in cortex and thalamus on delayed response in monkeys

Abstract Eighteen brain points in prefrontal and thalamic areas of each of three adult male macaques were tested for the effects of electrical stimulation and coagulation during the delayed response test. During the delay period, stimulation of prefrontal areas and dorsomedial thalamus caused severe impairment in two subjects. Stimulation caused less impairment during the baiting period than during the delay period; continuous stimulation throughout the test caused less impairment than intermittent stimulation; intermittent stimulation throughout the test was the most effective mode of stimulation. Distraction tests produced the same standard of performance achieved during control tests; peripheral shocks produced a slightly impaired performance. Even aversive peripheral stimuli did not produce as many errors as did central stimuli which produced no behavioral effects. Prefrontal lesions had more disruptive and longer-lasting effects than did thalamic lesions, but the order in which the lesions were made had no effect on performance. The results substantiate previous conclusions that electrical stimulation of points along the banks of the principal sulcus can impair the delayed response performance of overtrained subjects, but, on the other hand, stimulation of dorsomedial nucleus of thalamus has the same effect.
Retinal terminals in the goldfish optic tectum: Identification and characterization

Retinal terminal profiles in the goldfish optic tectum were identified electron microscopically after (1) labeling with horseradish peroxidase and (2) in the early stages of degeneration in short-term eye enucleates. All labeled terminals shared certain common morphological characteristics which were identical to those of a population of terminals in normal tecta. Terminals of this type disappeared 30 days after enucleation of the contralateral eye. Retinal terminal presynaptic profiles were characterized by (1) round and oval synaptic vesicles; (2) mitochondria with irregular, randomly oriented cristae, large intracristal spaces, dilated membrane spaces, and primarily light matrices; (3) a wide range in profile area, 0.06-6.82 pm2; (4) large numbers of synaptic vesicles per profile area (168+ 33 synaptic vesicles per pm2; (5) asymmetric synapses; and (6) multiple synaptic contacts (1.46 0.73 per terminal profile). The postsynaptic elements included both dendritic and, less commonly, pleomorphic vesicle-containing profiles. The majority of postsynaptic dendritic profiles were small (0.01-0.40 wm2). Serial synaptic contacts were occasionally seen. The combination of vesicular and mitochondria1 morphology (1 and 2 above) was necessary and sufficient to establish the retinal origin of a terminal, but use of such criteria would underestimate the number of retinotectal terminals by omitting those which did not have a mitochondrion in the plane of section. The number of such terminals was calculated from independent measurements, and the total number of retinal terminal profiles per area of neuropil was estimated.