cssi/SciSciGPT-SciSciNet huggingface dataset:
Empowering Teachers with Strategies for Efficient Learning and Functioning through Video-Assisted Staff Development.

This article describes a video-assisted staff development program that can be delivered at the building or district level. This report includes: (a) a critical perspective of staff development programs, (b) reconceptualization of staff development, (c) the use of video-mediated staff development, (d) a service delivery model known as “Professor Plus”, (e) the content of the video-assisted SELF training program, (f) the results of the program's pilot field test and, (g) the results of afield-based investigation designed to assess the effectiveness of the video-assisted SELF training program. The article concludes with a discussion of implications and future directions for this type of delivery model for staff development.
Monitoring of the Performance of Mechanical Roof Bolts in an Appalachian Coal Mine

SUMMARY A new type of roof bolt dynamometer has been developed to monitor changes in bolt tension with precision of +/-25 N. These dynamometers were installed in an Eastern Kentucky drift coal mine. At the monitoring site the immediate roof of Coalburg seam is composed of shale of varying thickness up to 1 m; thus the 1.2 m bolts were anchored in all cases in the overlying sandstone. The selected site was located in an intake airway about 600 m from a portal. It had a potential for roof problems due to sharp variations in air humidity, which is known to contribute to roof deterioration. Observation holes drilled in the mine roof were used for borescope inspection with miniature TV camera to localize and measure separation planes in situ. During the one year monitoring period the roof deteriorated considerably. Field data for this period illustrate changes in shaly roof. Analysis of the results is used as a base for the identification of the roof failure phenomena.
Fixation of hybrid vigor in rice: synthetic apomixis generated by genome editing

Apomixis is an asexual reproduction process in which clonal seeds are formed without meiosis and fertilization. Because of its potential in permanently preserving hybrid vigor, apomixis has attracted a great deal of interests from plant biologists and the seed industry. However, despite of decades of effort, introgression of apomixis traits from wild relatives into major crops has remained unsuccessful. Therefore, synthetic apomixis has been proposed as an alternative to fix hybrid vigor. In this article, I present the development of the MiMe (Mitosis instead of Meiosis), which turns meiosis into mitosis and leads to the production of clonal gametes. Apomixis-like clonal seeds are generated when MiMe plants are crossed to special genome elimination lines, which contain an altered centromere-specific histone 3 (CENH3). Furthermore, induction of haploid plants from egg cells can be achieved by either egg cell-specific expression of BABY BOOM1 (BBM1), or disruption of MATRILINEAL (MTL) using CRISPR/Cas9 gene-editing technology. Synthetic apomixis is established and clonal seeds are produced by simultaneous engineering MiMe with altering BBM1 expression or MTL disruption. Finally, I discuss how to further improve the apomixis strategy and its applications in crop breeding.
Analysis of Periorbital Soft Tissue in Thyroid Eye Disease

Purpose To investigate periorbital tissue enlargement in thyroid eye disease (TED) by 3-dimensional CT volumetric analysis. Methods Twenty-four adult subjects, 16 with TED and 8 controls, were studied. Three-dimensional volumetric calculations were performed on CT imaging of the orbit and face, focusing on the retroorbicularis oculi fat, suborbicularis oculi fat, facial muscles in periorbital region, orbital fat, extraocular muscles, and orbital volume. Analysis was performed using JMP version 12 software. Each measure was compared between the TED and control groups using Wilcoxon rank sum test. Correlations were investigated between periorbital and orbital tissue using the Spearman's correlation coefficient method. Results A statistically significant increase in volume was measured in TED patients in the superior and inferior periorbital fat tissue (p = 0.0044, p = 0.047), including the retroorbicularis oculi fat (p = 0.0011), suborbicularis oculi fat (p = 0.0093), and a decrease in facial muscle of superior periorbital region (p = 0.035). Strong positive correlation was noted between the muscles of superior and inferior periorbital region (rs = 0.65; p = 0.0006), and between the suborbicularis oculi fat and retroorbicularis oculi fat (rs = 0.50; p = 0.013). No correlation was observed between orbital and periorbital tissue, except between the orbital fat and the inferior periorbital fat tissue (p = 0.047). Conclusions Facial fat in the periorbital region is enlarged in TED, with the superior component correlating with orbital fat tissue expansion. These findings may assist in the clinical evaluation and management of disfigurement in TED patients.Superior and inferior periorbital fat is enlarged in thyroid eye disease with the superior periorbital fat expansion correlating with orbital fat expansion.
Heart rate and heart rate variability in emergency medicine.

Abstract Background Tachycardia may be indicative of mental stress, which in turn can decrease performance, reduce information processing capacity, and hinder memory recall. The objective of this study is to examine heart rate trends present among emergency medicine trainees over a standard emergency room shift to measure the frequency and severity of stress experienced while on shift. Methods We assessed heart rate in emergency medicine residents using the Empatica E4 device, a mobile wrist-worn physiological monitor. The 31 consenting residents received training in wearing the monitor and uploading the data during a typical critical care shift. Data was deindividualized, compiled, and analyzed with descriptive statistics using Microsoft Excel. Results Data collected from 31 critical care shifts illustrated that the mean range in HR was 53.9–162.7 bpm per shift and the overall range in HR across all shifts was 49–202.7 bpm. There was a mean of 10.2 peaks in the 120–129.9 bpm range, 11.3 peaks within 130–159.9 bpm, and 1.06 peaks above 160 bpm per shift. The mean length of time that HR rose above 130 bpm was 660.6 s per shift. Only 2 of the 31 shifts examined did not have any accelerations above 130 bpm. Conclusions Continuous monitoring of HR in emergency medicine residents during standard critical care shifts using a wrist-worn device found marked elevations suggestive of episodic tachycardia.
Clarifying the direction of impact of negative symptoms and neurocognition on prospective work functioning in psychosis: A 20-year longitudinal study

Abstract Both neurocognition and negative symptoms have demonstrated strong links to functional outcomes, such as work functioning, among those with severe mental illness (SMI). Prior models have suggested that reduced neurocognition 1) precedes or predicts greater negative symptoms and 2) indirectly influences functional outcomes via its impact on negative symptoms. The current study sought to also test a divergent model: whether greater negative symptoms predict reduced neurocognition and indirectly influence work functioning through their impact on neurocognition. Both models were tested using cross-sectional and prospective data spanning 20-years in a sample of 277 people with a SMI with psychotic features. Results showed that both models were supported in cross-sectional analyses. However, in prospective models predicting work functioning, only the models examining the indirect influence of negative symptoms on work functioning (7.5 to up to 20-years later) through neurocognition demonstrated significant mediation (i.e., a significant indirect effect); further, higher negative symptoms significantly predicted lower prospective neurocognition, while lower neurocognition did not significantly predict greater prospective negative symptoms. Although cross-sectional data were consistent with prior models, our prospective models offered greater support for a putative causal pathway running from negative symptoms to neurocognition—rather than the reverse—to work functioning. Findings have implications for mechanisms contributing to longitudinal work functioning and suggest that targeting negative symptoms prior to neurocognition could be more beneficial for long-term work outcomes.
Augmented-reality guided treadmill training as a modality to improve functional mobility post-stroke: A proof-of-concept case series.

Objective: To provide a proof-of-concept for a novel stroke-gait-specific augmented reality (AR)-guided treadmill intervention by evaluating its effect on temporospatial and functional outcomes of mobility.Methods: Two females with hemiplegia post stroke were recruited for participation in a 4-week intervention, and a single healthy control was recruited for baseline comparisons. The stroke-intervention (SI) participant (aged 54-years), completed 12 sessions of AR-guided treadmill intervention. The stroke-control (SC) participant (aged 59-years) completed 12 sessions of conventional treadmill intervention. Temporospatial and functional mobility were assessed pre-intervention, post-intervention, and at 1-month follow-up. Physical ACtivity Enjoyment Scale (PACES) was administered post-intervention.Results: The SI participant showed clinically meaningful improvements in functional outcomes post-intervention and at 1-month follow-up (Berg balance score (BBS): +6 and +10 points; Dynamic Gait Index (DGI): +2 at post-intervention only; walking speed: +0.19 and +0.24 m/s; 6-minute walk test (6MWT): +51.9 and +38.9) respectively. The SC showed clinically meaningful improvements in BBS (+3 and +3) and walking speed (+0.06 at post-intervention). The PACES scores showed that the SI participant had a significantly higher (23 points) enjoyment level during the intervention compared to the SC participant. The SI participant was more asymmetric compared to the SC participant at pre and post-intervention visits.Conclusions: The SI participant showed greater improvement in functional assessments compared to the SC participant post intervention. The AR-guided approach may have added benefits compared to traditional treadmill training, while providing better customization, patient enjoyment, and engagement. Further investigation with a larger sample is warranted.
Shift work and overtime across a career in law enforcement: a 15-year study

Purpose – To characterize changes in work hours across a career in law enforcement. Design/methodology/approach – N = 113 police officers enrolled in the BCOPS cohort were studied. The police officers started their careers in law enforcement between 1994 and 2001 at a mid-sized, unionized police department in northwestern New York and continued to work at this police department for at least 15 years. Day-by-day work history records were obtained from the payroll department. Work hours, leave hours and other pay types were summarized for each calendar year across their first 15 years of employment. Linear mixed-effects models with a random intercept over subject were used to determine if there were significant changes in pay types over time. Findings – A total of 1,617 individual-years of data were analyzed. As the police officers gained seniority at the department, they worked fewer hours and fewer night shifts. Total paid hours did not significantly change due to seniority-based increases in vacation time. Night shift work was increasingly in the form of overtime as officers gained seniority. Overtime was more prevalent at the beginning of a career and after a promotion from police officer to detective. Originality/value – Shiftwork and long work hours have negative effects on sleep and increase the likelihood of on-duty fatigue and performance impairment. The results suggest that there are different points within a career in law enforcement where issues surrounding shiftwork and long work hours may be more prevalent. This has important implications for predicting fatigue, developing effective countermeasures and measuring fatigue-related costs.
From Damage Caps to Decarceration:Extending Tort Law Safeguards to Criminal Sentencing

The Supreme Court has recognized a civil defendant’s substantive due process right not to be subject to grossly excessive punitive damage awards. Such awards – even if furthering legitimate state interests in retribution and deterrence – must not be grossly disproportionate to the compensatory damages reflecting the actual harm suffered by the plaintiffs. More concretely, the “multiplier” – the ratio of punitive to compensatory damages – cannot be too high, with anything exceeding a 10:1 ratio deemed presumptively excessive. This Article is the first to argue that a similar test should guard against grossly excessive criminal punishments; indeed, it seems odd that large corporations committing civil wrongs enjoy greater protection against overpunishment than criminal defendants, given the devastating effects of mass incarceration, particularly on communities of color. As we show, there are compelling constitutional, logical, and policy reasons to ensure that criminal punishments are not grossly disproportionate to the harm caused. In turn, although criminal courts might find the task of estimating the harm caused by a crime unfamiliar, we show how this could be done through surveys measuring the prison time a would-be victim would be willing to endure to avoid the crime. Scholars have used such error-preference surveys in other legal contexts, but not yet in determining proportionality of punishment. We offer a survey example as proof of concept and fodder for future research, and we report initial results corroborating the intuition that some crimes routinely trigger sentences grossly disproportionate to harm caused. Whether or not criminal courts impose due process limits on punishment, our arguments and findings can be wielded by litigants, judges, and policy advocates to argue for lower sentences in individual cases, as well as to push for critically overdue sentencing reform.
Implementation of novel TMS coils for multisite brain stimulations

Transcranial magnetic stimulation (TMS) is one of the most effective non-invasive neuromodulation techniques used to treat neurological and psychiatric disorders. It is also highly popular to be used for studying and understanding brain functions and mechanisms. Multisite simultaneous or sequential stimulation of different brain regions provides a new methodology to study and comprehend the functional dependence and causal relationships among different regions and networks. However, due to the large coil size, which doesn't allow more than two coils being simultaneously utilized, and the non-ideal field focality and penetration depth of existing commercial coils, multisite simulation methods have not been well exploited. In this study, an angle-wrapped and multi-stacked circular coil is proposed to form an array of coils and used for this purpose. The induced electric field hot spot of the single coil and the coil array designs for fixed multisite stimulation were studied with the finite element method. The FEM simulations were then verified with experiments performed on fabricated coils. The performed simulations and experiments indicated the proposed coils' enhanced performance regarding the hot spot size and electric field decay rate compared to conventional circular coils. The successfully demonstrated close proximity and small spot size of stimulation show great potential for future fixed and adjustable multisite brain stimulation.
Accounting for global value chains: rising global inequality in the wake of COVID-19?

Production processes depend on fragmented and interdependent value chains; nowadays, a single product often includes components produced in dozens of countries. Many public health measures being im...
Compartmentalization and Compromise: Colin Turnbull and the American Museum of Natural History African Hall

Colin Turnbull became Assistant Curator of African Ethnology at the American Museum of Natural History (AMNH) in 1959. In the next decade he did his major fieldwork on the Mbuti and the Ik, and also curated the AMNH African Hall, which, in only slightly altered form, remains open to the public today. Turnbull's writings in the 1960s and 1970s show that he was acutely aware of, and disturbed by, the rapid changes going in Africa in the late colonial period, as well as the burgeoning civil rights movement in the U.S. in the same period. Yet the African Hall shows only a little of this sensibility and according to many observers presents a somewhat romanticized view of a pre-colonial past. Using the idea of compartmentalization, this paper explores the content and lacunae in the AMNH African Hall, and speculates on how these commissions and omissions may relate to Turnbull's psychological state and to the institutional pressures he faced at the Museum in the 1960s.
Applying planned missingness designs to longitudinal panel studies in developmental science: An overview

Longitudinal panel studies are widely used in developmental science to address important research questions on human development across the lifespan. These studies, however, are often challenging to implement. They can be costly, time-consuming, and vulnerable to test-retest effects or high attrition over time. Planned missingness designs (PMDs), in which partial data are intentionally collected from all or some of the participants, are viable solutions to these challenges. This article provides an overview of several PMDs with potential utilities in longitudinal studies, including the multi-form designs, multi-method designs, varying lag designs, accelerated longitudinal designs, and efficient designs for analysis of change. For each of the designs, the basic rationale, design considerations, data analysis, advantages, and limitations are discussed. The article is concluded with some general recommendations to developmental researchers and promising directions for future research.
Commensal Candida Albicans Positively Calibrate Systemic Th17 Immunological Responses

Colonization with pathobiont microbes is a classical risk factor for invasive infection. However, the relative paucity of systemic infection despite ubiquitous pathobiont commensalism suggests colonization may also elicit protective host immunity. We show Candida albicans intestinal colonization of mice and humans drives systemic expansion of fungal-specific Th17 CD4+ T cells, and IL-17 responsiveness by circulating neutrophils, which synergistically protect against C. albicans invasive infection. Persistent C. albicans colonization is required, since protection is overturned by eradicating fungal colonization. Commensal C. albicans conferred protection extends to invasive infection by the extracellular bacterial pathogen, Staphylococcus aureus. However, positively calibrating systemic Th17 responses is not uniformly beneficial, as commensal C. albicans does not protect against intracellular influenza A virus infection, and exacerbates allergic airway inflammation susceptibility. Thus, systemic Th17 inflammation driven by CD4+ T cells responsive to commensal C. albicans tonic stimulation improves host defense against extracellular pathogens, but with harmful immunological consequences.
A Synthesis of Methods for Evaluating Interrelated Investment Projects

Strategic investments are frequently placed in increments through time, while simultaneously impacting other processes. These sources of dependency cause the economic evaluation of these projects to be a complex affair. There are a number of methods that allow the analyst to evaluate these types of investments. This paper identifies, explains, and provides practical examples for seven different evaluation methods. For each of these approaches we identify strengths, weaknesses, and best application. We conclude by suggesting that an approach that combines simulation with activity-based costing for tactical evaluation and expert systems for strategic evaluation may have the most future promise.
Calcium Oscillations in Neurons

Oscillations in the cytosolic free Ca2+ concentration ([Ca2+]i) have been described in a variety of cells. In some cases, [Ca2+]i oscillations reflect cycles of membrane depolarization and voltage-dependent Ca2+ entry. In others, they are caused by periodic Ca2+ uptake and release by internal stores, with little immediate requirement for external Ca2+. A third type of [Ca2+]i oscillation is typified by caffeine-induced oscillations in sympathetic neurons. Here, the oscillations depend on the interplay between Ca2+ transport across the plasma membrane and transport by a caffeine-sensitive store. These oscillations can occur at a steady membrane potential and are blocked by ryanodine (1 microM), indicating that they do not result from voltage-dependent changes in Ca2+ entry but do require Ca(2+)-induced Ca2+ release. Entry of Ca2+ from the external medium is important during all phases of the oscillatory cycle except the rapid upstroke, which is dominated by Ca2+ release from an internal store. It is proposed that caffeine-induced [Ca2+]i oscillations are cyclic perturbations of [Ca2+]i caused by exchange of Ca2+ between the cytosol and the caffeine-sensitive store: net Ca2+ loss from the store increases [Ca2+]i transiently above its steady-state value ([Ca2+]ss), whereas net accumulation of Ca2+ by the store transiently depresses [Ca2+]i below [Ca2+]ss. The effects of rapid removal of Ca2+ and caffeine on the rate of change of [Ca2+]i (d[Ca2+]i/dt) provide estimates of the rates of net Ca2+ entry and (caffeine-sensitive) Ca2+ release and information on the way these rates vary during the oscillatory cycle.
Overview of CIM-oriented database design and data exchanging in power system applications

Historically, databases in power systems were designed for certain applications and not oriented to information-sharing. The isolation among power system applications' databases hinders the development of a universal information infrastructure in the power system industry. To accommodate the trend of software development, the Electric Power Research Institute (EPRl) Working Group on Control Center Application Interfaces has published a standard data model-common information model (CIM) in IEC standard 61970. An overview of all the models is introduced. A central CIM database is proposed in this standard for large amount of common data-sharing among applications. Accordingly, conventions and procedures used to translate the CIM specification into a workable, "real-world" relational database are reaching maturity. EPRI also decided to use extensible markup language (XML) in resource descriptive frame (RDF) as the format for exchanging CIM data in power system applications and databases. This paper presents an overview of the CIM data models for power systems, the CIM implementations in database design, and the data exchange format for the applications.
Studies on the organization of the brush border in intestinal epithelial cells. V. Subfractionation of enzymatic activities of the microvillus membrane.

Abstract Isolated brush border membranes of the intestinal epithelial cell have been partially digested by treatment with low concentrations of papain. A multienzyme particle containing maltase, sucrase and isomaltase activities is released. Further treatment with papain releases leucyl naphthylamidase activity in particulate form. Trehalase activity remains with the residue of the membrane. The disaccharidase-containing particles can be separated from those containing leucyl naphthylamidase on Sephadex G-200 columns. Alkaline phosphate activity is rapidly destroyed by papain treatment. Leucyl glycine-splitting activity can be separated from leucyl naphthylamide-splitting activity by papain treatment. Thus there is now evidence for two brush-border enzymes involved in the digestion of peptides. The association of membrane enzymes with particles containing multiple activity is in accord with the view of a mosaic substructure of the membrane.
Isolated modular multilevel (IMM) DC/DC converter with energy storage and active filter function for shipboard MVDC system applications

Nowadays more and more pulsed loads and nonlinear loads are carried on the medium-voltage (MVDC) shipboard power system, the pulse and non-linear current in different frequency ranges might induce voltage oscillations on the MVDC bus. In this paper, a novel galvanic isolated bidirectional dc/dc converter based on modular multilevel converter (MMC) with energy storage and dc active power filter function is proposed which features smoothing load current on the MVDC bus. Detailed system analysis and control strategy are presented. The simulation results are provided as well to verify the operation and functionality of the proposed system.
Prevalence of daytime sleeping in the working population from estimates of nocturnal work shift

Background: Sunlight has been linked the circadian rhythms that regulate sleep. Few studies have attempted to provide estimates on the size of the “daytime sleeper” population. Specific aims: Estimate prevalence of daytime sleepers in the labor force population and identify which demographic characteristics are risk factors for daytime sleeping. Methods: Cross-sectional, community-dwelling, nationally representative, observational study used information on 6,405,063 labor force participants representing 132,682,344 individuals in the contiguous United States. Data from the American CommunitySurvey (ACS), Public Use Microdata Sample (PUMS), 2009-2013 (5-year) file was used to identify daytime sleepers ( i.e. , those who arrived at work between 7:00 PM and 2:59 AM). Findings: While nighttime sleepers represented 65.9% (n = 87,426,814) of those in the labor force population, daytime sleepers represent 3.3% (n = 4,344,311). Race-ethnic minority status, being disabled, and having low levels of educational attainment were found to be risk factors for daytime sleeping. Conclusions: Even though relatively small, the objectively large (4.3 million) number of daytime sleepers requires sleepresearch to invest resources in understanding how health varies in this population relative to those who primarily sleep in theabsence of sunlight.
Constructing perceptual categories

It is shown how a parameterization of the structure of the observed object (interpretable as the space of dimensions of generative operations which brought the object into existence) entails a lattice that enumerates all the allowable categories and subcategories for the class of object, along with an inferential preference hierarchy among them. Each model is constrained to be generic in its parameterization, so that each node in the lattice stands in for an entire class of objects that, all being parameterized the same way, can all be treated as equivalent to one another: the observed object's natural category. >
A Distributional Approach for Single Factor Option Valuation Models

This paper presents a distribution approach to valuing options where the reference variable is either normally or lognormally distributed. The general results presented here can be applied to a wide class of stochastic differential equations. The approach taken here deviates from the standard equivalent martingale measure approach. This distribution approach is well suited for markets where forming self-financing, dynamic replicating portfolios are fictional, such as credit, energy, weather, emissions, and many applications of real options theory. Alternatively, the distribution approach can assist counterparties in appraising the usefulness of a particular option for their risk management needs. The resulting models have the flexibility to incorporate factors such as liquidity discounts.
Facilitating México-US Higher Education Collaboration: Perspectives of U. S. Border Academics

El Tratado de Libre Comercio (TLC) ha contribuido al incremento de colaboracion entre las instituciones de educacion superior mexicanas y estadounidenses, especialmente en la frontera. El incremento resulto en literatura enfocada en retos, impacto, necesidad y prospectos de colaboracion. Aun asi, hasta 2001, no se encontro un estudio para describir si existian caracteristicas personales e institucionales que facilitaran la colaboracion. Entonces, el proposito de este estudio fue explorar tales caracteristicas. Para iniciar esta exploracion, las perspectivas de academicos en la frontera norte fueron obtenidas. Sus perspectivas fueron juntadas con un cuestionario con preguntas extraidas de investigaciones sobre la colaboracion y de otros temas relacionados. Los resultados del estudio verificaron la existencia de caracteristicas que se pueden resumir como compromiso y competencia transcultural. Unas recomendaciones basadas en los resultados del estudio concluyen este articulo
Associating quantum vertex algebras to deformed Heisenberg Lie algebras

We associate quantum vertex algebras and their ϕ-coordinated quasi modules to certain deformed Heisenberg algebras.
Arginine kinase: Differentiation of gene expression and protein activity in the red imported fire ant, Solenopsis invicta

Arginine kinase (AK), a primary enzyme in cell metabolism and adenosine 5'-triphosphate (ATP)-consuming processes, plays an important role in cellular energy metabolism and maintaining constant ATP levels in invertebrate cells. In order to identify genes that are differentially expressed between larvae and adults, queens and workers, and female alates (winged) and queens (wingless), AK cDNA was obtained from the red imported fire ant. The cDNA sequence of the gene has open reading frames of 1065 nucleotides, encoding a protein of 355 amino acid residues that includes the substrate recognition region, the signature sequence pattern of ATP:guanidino kinases, and an "actinin-type" actin binding domain. Northern blot analysis and protein activity analysis demonstrated that the expression of the AK gene and its protein activity were developmentally, caste specifically, and tissue specifically regulated in red imported fire ants with a descending order of worker> alate (winged adult) female> alate (winged adult) male> larvae> worker pupae approximately alate pupae. These results suggest a different demand for energy-consumption and production in the different castes of the red imported fire ant, which may be linked to their different missions and physiological activities in the colonies. The highest level of the AK gene expression and activity was identified in head tissue of both female alates and workers and thorax tissue of workers, followed by thorax tissue of female alates and abdomen tissue of male alates, suggesting the main tissues or cells in these body parts, such as brain, neurons and muscles, which have been identified as the major tissues and/or cells that display high and variable rates of energy turnover in other organisms, play a key role in energy production and its utilization in the fire ant. In contrast, in the male alate, the highest AK expression and activity were found in the abdomen, suggesting that here energy demand may relate to sperm formation and reproduction.
Interfacial Shear Behavior of Sapphire-Reinforced NiAi Composites

The interfacial shear behavior in near-equiatomic NiAl reinforced by sapphire filaments has been examined at room temperature using a fiber pushout test technique. The load-displacement data indicate a large variability in the initial interface failure stress, although reverse push behavior indicates a comparatively constant interfacial sliding friction stress. The observed behavior suggests that the presence of asperities on the fiber surfaces and nonuniformities in fiber diameter require constrained plastic flow within the NiAl matrix in order for interfacial shear to occur. The location, shape, severity, and distribution of fiber asperities as well as the uniformity of fiber diameter are critical to the interfacial shear process.
A Lie algebra generalization of the Amitsur-Levitski theorem

0.1. If R is any algebra over a field F and xi E R, i= l,..., k, let IIX 1 ,..., .Y~] 1 E R denote the alternating sum of products Z: sg 0 x,,(,) *** x,,(~) over all permutations 0 of l,..., k. One says that R satisfies the k-fold standard identity if [IX, ,..., xk]] = 0 for any choice xi E R. Of course if PC_ R is any subspace of R one can restrict one’s attention to P and say that P satisfies the k-fold standard identity if 1 [x1 ,..,,x~]] = 0 for any choice xi f P. Now the Amitsur-Levitski theorem asserts that the n X n matrix algebra M(n, F) satisfies the 2n-fold standard identity. (For a survey and history of this theorem see [ 9 1. See also 17 I.) It is of course enough to consider the case where F = C. Some time ago (see [3]) we came upon a proof of the Amitsur-Levitski theorem from the point of Lie algebra cohomology. The cohomology of M(n, C) as a Lie algebra is an exterior algebra with primitive generators having degrees, 1, 2,..., 2n 1. The failure of M(n, Cc) to have a primitive class in degree 2n + 1 leads to the trace relation tr[ [x, ,...,x~~+,]] = 0 for any xi E M(n, C;). for i = I ,..., 2n + 1. But this quickly implies the Amitsur-Levitski theorem. In fact the argument can be pushed further. If d, G M(n. Cc) denotes the Lie algebra of all n x n skew-symmetric matrices one knows that d,, has no primitive class in degree 2n 1 in case n is even. This led to a new identity in [3 1. For iz even
Dispersal of Mediterranean and Suez Bay sediments in the Suez Canal

Abstract This study determines the extent to which sediments of Mediterranean, Suez Bay, and in-situ (authigenic, eroded channel) derivation have been displaced along the Suez Canal. Sediment transport is largely a response to hydrodynamics controlled by markedly different oceanographic conditions at both ends of the channeled byway. Petrology of sand, silt and clay fractions determine distributions of diagnostic tracer minerals. These are used to identify five sediment provinces in the canal which indicate long-term dispersal patterns. Sediments of Mediterranean origin (largely terrigenous from the Nile River) are transported southward to Ballah Bypass, while those of Suez Bay—southern Canal derivation (mixed carbonate and terrigenous) are transported northward to the northern edge of Great Bitter Lake. In-situ derived Bitter Lakes sediments, mostly carbonates, are not transported extensively from the lakes area. Similarly derived Lake Timsah sediment is transported into the short stretches of the canal to the north and south of the lake. The canal south of Little Bitter Lake is a zone of erosion, while the Bitter Lakes are sinks for sediments from several sources.
Teacher Re‐creation of Negative Interactions with Toddlers

Fifty two‐year olds and fifty three‐year olds from low‐income families were observed in 10 urban day care centers serving disadvantaged families. Microanalytic chains of child‐teacher interactions were recorded and then recoded to represent positive and negative behaviors. Two‐year old male toddlers behaved more negatively than two‐year old girls or three‐year old children. In turn, male toddlers elicited more negative behaviors from their caregivers. Teachers seemed to be controlled by children's behaviors—responding positively to positive behaviors and negatively to negative behaviors. Providers may unwittingly recreate in group care the negative interactions, predictive of poor socioemotional adjustment, that toddlers are already experiencing at home. These data have important implications for mental health toddler workers involved in training teachers in early childhood settings.
Why search committees must be wary of ex-cavalry officers, Condorcet's paradox, and dictators

Given the current emphasis placed on affirmative action, it should come as a shock to many participants on selection committees to find that the most used balloting rule employed to determine the will of the committee is seriously flawed. The procedure, whereby candidates are assigned points based upon each voter's ranking, can frequently lead to a winner who is not the choice of the majority—a violation of the most central democratic concept. More surprising is the fact that the unsuitability of such weighted balloting has been known for over 200 years and that a Nobel Prize was awarded as recently as 1972 for research closely related to this problem. This paper traces the history of the research for a perfect, logical, democratic balloting rule, taking the reader through the paradox discovered by the Marquis Condorcet and Arrow's dictator theorem. A detailed exposition of “approval voting” explains why this new approach is gaining in popularity as perhaps the most reasonable replacement for the various voting rules now in effect.
Molecular biology: Bound to splice.

Messenger RNAs don't usually correspond exactly to DNA — portions of the primary transcript, known as introns, are removed by splicing. A study reveals new ways in which splicing can be regulated. Genome-wide analyses in yeast have shown that the switch from mitosis to gamete-forming meiosis is associated with a dramatic change in gene expression profiles. One protein expressed only during meiosis is the cyclin Rem1, which enhances pre-meiotic intragenic recombination and ensures progression through meiosis. Moldon et al. now show that Rem1 expression in the fission yeast Saccharomyces pombe is controlled not only at the level of transcription, but also by splicing. In mitotic cells, binding of the Fkh2 transcription factor to the Rem1 promoter yields a transcript that retains its introns so that only a short protein is produced; this protein affects recombination levels. In meiotic cells, binding of a meiosis-specific transcription factor, Mei4, to the Rem1 promoter results in splicing of Rem1, and the active cyclin. Thus two transcription factors can differentially modify splicing of the same gene.
π-Overlap, pyramidalization and protonation of group 15 heterocycles. The basicities of the “higher pyridines”

Abstract The proton affinities of pyridine and the “higher pyridines” phosphorin, arsenin and antimonin, and of Me 3 N, Me 3 P, Me 3 As and Me 3 Sb, were explored via PM3 semi-empirical studies on the conjugated heterocycles (CH) n EH ( n = 2, 4; E = N, P, As, Sb), (CH)aE ( n = 3, 5; E = N. P. As. Sb) and (CH) n EH + ( n = 3, 5; E = N, P, As, Sb). The primary reason for the experimentally observed decline of heteroatom proton affinities in heterobenzenes (CH) 5 E (N s> P > As), relative to the saturated species (CH 3 ) 3 E, was found to be the increasing energetic cost of planarization of the EH fragment in (CH) 5 EH + combined with decreasing compensation for this cost by π-orbital overlap of planar EH with the (CH) 5 fragment. This energetic trade-off ultimately led to loss of planarity in the protonated heterobenzenes: the PM3-optimized structure for 1-antimoninium predicted the SbH fragment to be pyramidal with a 98° dihedral angle to the puckered ring.
Thyrotropin-releasing hormone-immunoreactive neurons project from the ventral medulla to the intermediolateral cell column: Partial coexistence with serotonin

Projections from medullary thyrotropin-releasing hormone (TRH) containing neurons to the intermediolateral cell column (IML) of the thoracic spinal cord were studied in the rat. Lesions of the ventral medullary reticular formation nuclei, nucleus paragigantocellularis lateralis and nucleus interfascicularis hypoglossi, decreased the thyrotropin-releasing hormone immunoreactivity in the IML. The ventral horn and dorsal horn contents of TRH were also reduced in rats with nucleus paragigantocellularis lateralis lesions. Coexistence of spinal cord TRH and serotonin was evaluated and quantified in 5,7-dihydroxytryptamine-treated rats. Treatment with the serotonin neurotoxin reduced the TRH content of the IML by 45% and of the ventral horn by 92%. These data show that TRH containing neurons project from the ventral medulla to IML and that approximately one-half of these TRH neurons are also serotonergic. Comparisons of the effects of the same lesions on the substance P and TRH content of the IML show that neither the origin of the SP and TRH neuronal projections to the IML, nor their coexistence with serotonin, are identical.
Design of oxidation-resistant coatings for high-temperature composites

Fabrication of oxidation-resistant carbon fiber reinforced carbon composites requires use of high-temperature CVD deposition of coatings such as SiC. In this paper the use of low-temperature chemical approaches for depositing oxidation-resistant coatings was explored. Coatings of SiO2, B2O3, and SiC were examined, with the intent of distinguishing possible failure mechanisms. Factors contributing to poor oxidation resistance of these coatings include presence of microcracks in the original preparation of the coating and diffusion of oxygen through the coating at high temperatures.
Smart repeater system for communications interoperability during multiagency law enforcement operations

A prototype 'smart' repeater that provides interoperability capabilities for radio communication systems in multi-agency and multi-user scenarios is being developed by the Oak Ridge National Laboratory. The smart repeater functions as a deployable communications platform that can be dynamically reconfigured to cross-link the radios of participating federal, state, and local government agencies. This interconnection capability improves the coordination and execution of multi-agency operations, including coordinated law enforcement activities and general emergency or disaster response scenarios. The repeater provides multiple channels of operation in the 30-50, 118-136, 138-174, and 403-512 MHz land mobile communications and aircraft bands while providing the ability to cross-connect among multiple frequencies, bands, modulation types, and encryption formats. Additionally, two telephone interconnects provide links to the fixed and cellular telephone networks. The 800- and 900-MHz bands are not supported by the prototype, but the modular design of the system accommodates future retrofits to extend frequency capabilities with minimal impact to the system. Configuration of the repeater is through a portable personal computer with a Windows-based graphical interface control screen that provides dynamic reconfiguration of network interconnections and formats.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The Impact On Mortality Of Antenatal Corticosteroids and Postnatal Surfactant In Preterm Infants. 1222

The Impact On Mortality Of Antenatal Corticosteroids and Postnatal Surfactant In Preterm Infants. 1222
Heart and en-bloc thymus transplantation in miniature swine.

Background Donor-specific tolerance to organ allografts might be induced by cotransplantation of a sufficient amount of vascularized donor thymus. To facilitate donor thymus-induced cardiac allograft tolerance, we have developed a novel technique for heart and en-bloc thymus transplantation in swine. Methods Donor heart and en-bloc thymus grafts were prepared by a technique that preserves the entire arterial supply and venous drainage of the right thymic lobe. En-bloc grafts (n = 4) were transplanted heterotopically into the abdomens of major histocompatibility complex-matched miniature swine. Recipients received 12 days of cyclosporine intravenously. Grafts were monitored by palpation, electrocardiographic monitoring, and periodic open biopsy. Engraftment of the donor thymus was demonstrated by measuring the proportion of recipient-type thymocytes in the donor thymus with flow cytometry. Results All of the heart and en-bloc thymus grafts had normal cardiac contractility and immediate perfusion of the thymus. All en-bloc grafts were accepted for more than 200 days without significant acute cellular rejection or cardiac allograft vasculopathy. Thymic tissue of en-bloc grafts displayed normal architecture and supported thymopoiesis of recipient-type cells. Conclusion We have validated a new technique of donor thymus transplantation that could have utility in human heart transplantation.
The nature of postasphyxial rigidity examined by intracellular recording from motoneurons.

Abstract The spinal cord of cats was asphyxiated for about 30 min by increasing the pressure in the dural cavity above the blood pressure. The resulting rigidity in the hind legs was investigated with intracellular methods 2 weeks after asphyxiation. Spontaneous action potentials were obtained which originated in three structures. Spikes were recorded from primary afferent fibers. Some of these could be identified as afferents of stretch receptors in extensor muscles by the enhanced rate of discharge when the rigid leg was flexed. Spontaneous spikes were also obtained from motor fibers. These structures were identified by antidromic stimulation. More complicated potentials were obtained from structures which were probably motoneuron somas. In a few instances the identification was made by antidromic stimulation. The potentials consisted of spikes and small potential fluctuations in the interspike interval. The latter were considered to be synaptic noise. In a regularly discharging soma the spike was followed by a (relative) hyperpolarization after which the soma depolarized until threshold for the subsequent spike was reached. Somas discharging at low frequency exhibited an irregular base line due to the synaptic noise. Depolarizations of greater magnitude were caused presumably by bunching of excitatory postsynaptic potentials; these occasionally elicited a spike. Flexion of the rigid hind leg tended to cause an increase in the rate of the “spontaneous” discharging soma, or to initiate an impulse train in quiet somas. It was concluded that the postasphyxial rigidity investigated is of a reflexogenic nature.
Note on graphs without repeated cycle lengths

In this note we prove that every 2-connected graph of order n with no repeated cycle lengths has at most $n + \sqrt{2(n - 2)} - 1$ edges and we show this result is best possible with the correct order of magnitude on $\sqrt{n}$. The 2-connected case is also used to give a quick proof of Lai's result on the general case. © 1998 John Wiley & Sons, Inc. J. Graph Theory 29: 11–15, 1998
Nanomanufacturing Strategy for Aligned Assembly of Nanowire Arrays

The work reported here concerns a proposed nanomanufacturing strategy to assemble aligned quasi-one-dimensional nanostructure arrays with intrinsic and concurrent control over the resultant number, pitch, and linewidth. For the first time, a standard lithography and crystallographic etching approach have been combined to synthesize periodic, sublithographic, and line edge roughness (LER)-free surface arrays for selective conjugation of nanowires. Key experimental modules have been developed, including the formation of LER-free substrate arrays, formation of periodically dissimilar surfaces, selective conjugation of nanowires, and stamping transfer of nanowire arrays. In particular, successful assembly of Si nanowires onto periodic Si/SiO x surfaces and subsequent transfer of the resultant aligned Si nanowire arrays onto a different substrate surface have been repeatedly demonstrated. The dependences and probability of nanowire aligned assembly have also been examined. The proposed strategy is based on a wafer-scale and very large-scale integration (VLSI)-compatible philosophy, and alignment to pre-existing features on the target substrate is also inherently allowed as a side benefit. Besides, LER-free features could be created, which arguably enables extreme linewidth scaling with suppressed variations.