cssi/SciSciGPT-SciSciNet huggingface dataset:
Mothering in the Context of Mental Disorder: Effect of Caregiving Load on Maternal Health in a Predominantly Hispanic Sample.

BACKGROUND: Mothering in the context of mental disorders presents with multiple challenges. However, this phenomenon is poorly understood: It is not known how child caregiving affects the health of...
3D porous chitosan-chondroitin sulfate scaffolds promote epithelial to mesenchymal transition in prostate cancer cells

Prostate cancer (PCa) is a common cancer in men that is curable prior to metastasis, when its prognosis worsens. Chondroitin sulfate (CS) is found in the extracellular matrix of normal prostate tissue and PCa, with greater content in metastatic PCa. Biomaterial scaffolds containing CS have yet to be evaluated for tumor microenvironment applications. Three-dimensional porous chitosan-CS (C-CS) scaffolds were developed and evaluated for PCa culture. Three C-CS scaffold compositions were prepared with 4 w/v% chitosan and 0.1, 0.5, and 1.0 w/v% CS and named 4-0.1, 4-0.5, and 4-1, respectively. The C-CS scaffolds had 90-95% porosity, average pore sizes between 143 and 166 μm, and no significant difference in scaffold stiffness. PC-3 and 22Rv1 PCa cells were cultured on the C-CS scaffolds to study the effect of CS on PCa growth and epithelial to mesenchymal transition (EMT). All C-CS scaffold compositions supported PCa growth and the 4-1 scaffolds had the greatest cell numbers for both PC-3 and 22Rv1. The C-CS scaffolds promoted upregulated EMT marker expression compared to 2D cultures with the greatest EMT marker expression in 4-1 scaffolds. Increasing CS concentration promoted upregulated vimentin expression in PC-3 cultures and N-cadherin and MMP-2 expression in 22Rv1 cultures. C-CS scaffolds promoted docetaxel drug resistance in PC-3 and 22Rv1 cultures and the 4-1 scaffold cultures had the greatest drug resistance. These results indicate that C-CS scaffolds are a promising in vitro platform for PCa.
Visualizing implementation: contextual and organizational support mapping of stakeholders (COSMOS)

While stakeholder mapping is common in public policy, social sciences, and business management, this tool has not often been used in healthcare settings. We developed a new method of healthcare stakeholder mapping, which we call Contextual and Organizational Support Mapping of Stakeholders (COSMOS), to identify and assess key stakeholders in an implementation project. Stakeholder mapping allows the implementation team to assess and visually display all relevant stakeholders, their support for the project, and their ability to facilitate—or hinder—project implementation. The COSMOS model was developed to visualize the stakeholders involved in a hospital-based study conducted from 2013–2016. In this study, a new screen prompt and order set were embedded in the electronic health record to facilitate the identification and treatment of adult smokers admitted to the hospital. Physicians were the unit of randomization; physician behavior and tobacco quit rates among patients were followed for 1 year. Qualitative interviews with hospital administration, physicians, and information technology (IT) personnel (n=24) were conducted to identify the components and characteristics of the COSMOS. The COSMOS consists of an organizational chart identifying all key stakeholders, with manipulation of colors and borders of the component boxes to indicate stakeholder support for the implementation project, and degree of criticality to its success. The COSMOS visualization informed the team’s subsequent work by identifying potential impediments that might require additional attention to garner and maintain support throughout the project. In addition, the approach has proved to be a useful tool to explain these concepts to trainees in implementation science. The COSMOS schematic provides a visually rich means of identifying stakeholders, understanding their relationships to each other, displaying their level of support for the proposed implementation, and noting their criticality to the effort. The COSMOS can support researchers, project teams, administrators, and others engaged with implementation science-related work in healthcare, as well as other fields such as education, government, and industry.
I-BERT: Inductive Generalization of Transformer to Arbitrary Context Lengths

Self-attention has emerged as a vital component of state-of-the-art sequence-to-sequence models for natural language processing in recent years, brought to the forefront by pre-trained bi-directional Transformer models. Its effectiveness is partly due to its non-sequential architecture, which promotes scalability and parallelism but limits the model to inputs of a bounded length. In particular, such architectures perform poorly on algorithmic tasks, where the model must learn a procedure which generalizes to input lengths unseen in training, a capability we refer to as inductive generalization. Identifying the computational limits of existing self-attention mechanisms, we propose I-BERT, a bi-directional Transformer that replaces positional encodings with a recurrent layer. The model inductively generalizes on a variety of algorithmic tasks where state-of-the-art Transformer models fail to do so. We also test our method on masked language modeling tasks where training and validation sets are partitioned to verify inductive generalization. Out of three algorithmic and two natural language inductive generalization tasks, I-BERT achieves state-of-the-art results on four tasks.
Congenital Lung Malformations

Congenital lung malformations are a rare but important disorder which can be associated with significant morbidity and mortality. The malformation may be identified during prenatal sonography, presented as respiratory distress in the newborn, or be completely asymptomatic and incidentally discovered in an adult.
Analysis of proportional data in reproductive and developmental toxicity studies: Comparison of sensitivities of logit transformation, arcsine square root transformation, and nonparametric analysis.

BACKGROUND In developmental and reproductive toxicity studies, analysis of litter-based binary endpoints (e.g., incidence of malformed fetuses) is complex in that littermates often are not entirely independent of one another. It is well established that the litter, not the individual fetus, is the proper independent experimental unit in statistical analysis. Accordingly, analysis is often based on the proportion affected per litter and the litter proportions are analyzed as continuous data. Because these proportional data generally do not meet assumptions of symmetry or normality, data are typically analyzed by nonparametric methods, arcsine square root transformation, or logit transformation. METHODS We conducted power calculations to compare different approaches (nonparametric, arcsine square root-transformed, logit-transformed, untransformed) for analyzing litter-based proportional data. A reproductive toxicity study with a control and one treated group provided data for two endpoints: prenatal loss, and fertility by in utero insemination (IUI). Type 1 error and power were estimated by 10,000 simulations based on two-sample one-tailed t tests with varying numbers of litters per group. To further compare the different approaches, we conducted additional analyses with shifted mean proportions to produce illustrative scenarios. RESULTS Analyses based on logit-transformed proportions had greater power than those based on untransformed or arcsine square root-transformed proportions, or nonparametric procedures. CONCLUSION The logit transformation is preferred to the other approaches considered when making inferences concerning litter-based proportional endpoints, particularly with skewed distributions. The improved performance of the logit transformation becomes increasingly pronounced as the response proportions are increasingly close to the boundaries of the parameter space.
Management Consulting Intervention Case Study in a Complex and Toxic Hospital Organizational Culture

Healthcare organizations in turmoil often turn to management consultants to collect data, engage in analysis, evaluate processes, and make recommendations. This is a case study of an actual hospital with complex issues around organizational culture, organizational conflict, diversity, and talent management. The paper explores the intervention approaches used to address the toxic organizational cultural problems through the lens of organizational development, change management, and corporate behavioral theory.
The handbook of mental health and aging

The Handbook of Mental Health and Aging, Third Edition, provides a comprehensive and timely account of accelerating scientific activity and progress related to mind/brain health and aging. It cover...
Time-based hypercompetition

During the past two decades, the notion of hypercompetition has challenged the conventional strategic thinking. Most of the essential concepts in hypercompetition are time-related. Although the importance of time-based competition (TBC) has been well recognised for decades, the high uncertainty and risk produced by hyperchanges further challenge the effectiveness of the 'traditional' TBC. This paper critically evaluates the feasibility of applying the traditional TBC to hypercompetition. Several themes of time philosophy are addressed in the discourse on the transition from the traditional TBC to the time-based hypercompetition (TBHC). Among them, we emphasise the importance of widening the here-and-now concept to go beyond its old 'present moment' connotation. We conclude the paper by proposing a new theory of hypercompetition: competition is really a non-issue in hypercompetition; firms simply challenge themselves to create new targets for others to follow.
Shear wave elastography in ex vivo and in vivo skin using high-frequency ultrasound imaging

Real-time, high-resolution imaging of the skin, including epidermal and dermal structures, is now possible using high-frequency ultrasound scanning systems. Potential extensions include shear-wave elastography. In this study, feasibility for characterization of skin layer elasticity using high-frequency ultrasonic imaging is demonstrated using a 50 MHz linear array and a small-animal ultrasound scanner (Vevo 2100, MS700 array). High-frequency time-harmonic shear wavefields (2-5kHz) are generated in the skin using a mechanical shaker. Wavefields are mapped by processing pulse-echo image sequences recorded at relatively low frame rates (513 fps), accounting for effects of signal aliasing and timing of multiple scan lines. Shear wavespeeds are then measured in ex vivo porcine skin and in vivo human forearm skin using spatial Fourier analysis, linear regression of measured wavefield phase maps, and algebraic inversion of wavefields using a finite difference method. Results demonstrate consistent measurements of shear wavespeed in the skin.
The Effects of Perioperative Transfusion of Allogenic Blood Products of Cancer Recurrence

Persons undergoing cancer resection surgeries often receive perioperative blood transfusions (PBT) to correct underlying anemia and optimize patient outcomes, namely post-surgical survival. However, there exists a host of emerging evidence suggesting that PBT may drive cancer recurrence and lower long-term disease-free survival. The prevailing theory for this phenomenon suggests that transfusion related immunomodulation (TRIM) downregulates immunogenic machinery in the transfusion recipient and facilitates the production of an oncogenic host environment. Notably, there also exist some studies suggesting that clinical parameters – ranging from cancer severity to performance status – may be ultimately more responsible than PBT in mediating cancer recurrence risk. A clear understanding of PBT induced cancer recurrence has yet to be clearly elucidated. Regardless of the precise molecular mechanisms, judicious transfusion practices are necessary to optimize patient safety profiles and long-term disease-free survival. Unfortunately, this concern of PBT conferred cancer recurrence is still novel and further studies exploring underlying mechanisms, such as TRIM, and directing clinical practice patterns for PBT usage are necessary.
Security Challenges and Future Applications of Smart Devices Based on Internet of Things

With the Internet of Things (IoT) step by step developing as the ensuing period of the advancement of the Internet, it gets critical to perceive the different expected areas for the use of IoT and the research challenges that are related with these applications — going from brilliant smart cities, to health care services, smart agriculture, coordination and retail. IoT is required to invade into for all intents and purposes for all parts of the day by day life. Even though the current IoT empowering technologies have enormously improved in the ongoing years, there are as yet various issues that require consideration. Since the IoT idea results from heterogeneous technologies, many research challenges will undoubtedly emerge. The way that IoT is so sweeping and influences all parts of our lives makes it a considerable research theme for concentrates in different related fields, for example, data technology and computer science. Accordingly, IoT is preparing for new elements of research to be completed. This paper presents the ongoing advancement of IoT technologies and examines future applications and research challenges.
Hardware-based microgrid testbed to facilitate development of Distributed Energy Resource (DER) systems for sustainable growth

Distributed energy resource (DER) systems that can combine small-scale conventional energy sources with diverse renewable energy options and storage are ideal for addressing electrification needs of small communities, as well as proactively mitigating negative impacts of fossil energy sources on the environment. It is therefore imperative for academic institutions that wish to play a role in addressing energy challenges for sustainable rural development to be adequately equipped with a hardware testbed for the study and analysis of DER systems. This work features a 45kW hardware testbed installation at Penn State Harrisburg, highlighting its design, construction, and its uses in academic instruction and research. A case study on electric loading characteristics of the network is presented to illustrate its relevance and the potential for its use in preparing a skilled workforce for a new energy economy.
P59 Parenting and Snacks: A Mixed Methods Study to Guide Intervention Development

Background Recent work in family nutrition suggests a focus on snacking, since children's snacks are often lower in nutrients than foods served at mealtime and have increased in frequency and caloric contribution. Developing healthy snacking habits in early life may impact the trajectory of snacking behaviors later in life. Objective To explore the relationships between snacking patterns and snack-related parenting; and drivers of snacking decisions and desired support for parents. Study Design, Setting, Participants A mixed-methods approach was used among student parents whose child(ren) attended a preschool program at a Southern California university. Measurable Outcome/Analysis A modified version of the Snack Intake Frequency Questionnaire and the Parenting around Snacking Questionnaire (P-SNAQ) were used to explore correlations between snacking patterns and snack-related parenting. Three focus groups were conducted to identify drivers of snacking decisions and to guide design of healthy snacking intervention strategies. Focus group transcripts were coded using thematic analysis by 2 independent coders. Results Survey participants (n = 42) were predominantly female (n = 35) and identified as Hispanic/Latino (n = 19). Findings indicated positive correlations between frequency of offering healthy snacks and reasoning/support for healthy snacks (r = 0.43, P = 0.006) and snack planning/routines (r = 0.37, P = 0.02); a negative correlation between frequency of unhealthy snacks and availability of healthy snacks (r = -0.32, P = 0.04); and negative correlations between parent age and emotion-based snacking (r = -0.46, P = 0.003), snacks as rewards (r = -0.35, P = 0.03), and snacks to manage behavior (r = -0.45, P = 0.005). Focus group findings (n = 11) suggest parents balance priorities when making snacking decisions, including health, behavior control, convenience/accessibility, parent/child roles, and social influences. Parents suggested a snacking-focused class with information on snacking strategies and social support. Conclusion Findings suggest younger parents may benefit from snacking-focused intervention programs that support healthy snacking routines and alternative behavior management strategies for children.
Sarcoidosis presenting as bilateral lacrimal gland swelling: a pediatric case report.

Background To describe a case of pediatric sarcoidosis which initially presented as papillary conjunctivitis before manifesting as bilateral lacrimal gland swelling without other known systemic involvement. Case presentation A 10-year-old female presented to the pediatric ophthalmology clinic with complaints of bilateral eyelid swelling, tearing and itching for approximately 1 month. Her history and exam were most consistent with allergic conjunctivitis, for which she was started on a standard topical regimen. Despite initial improvement, she re-presented with significantly worsened eyelid swelling and minimal allergic symptoms. Enlargement of the lacrimal glands were palpable at this time. Lacrimal gland biopsy was obtained which demonstrated noncaseating granulomas. Systemic workup did not reveal evidence of disease involvement elsewhere. Conclusions Sarcoidosis in the pediatric population may present in a myriad of ways and is well-known to mimic other disease entities. We present a case of pediatric sarcoidosis which presented initially as papillary conjunctivitis before manifesting as bilateral lacrimal gland swelling without systemic involvement.
Siple station experiments on wave-particle interactions in the magnetosphere

Natural and controlled whistler-mode signals have been used at Siple Station (and its conjugate, Roberval, Quebec) to study nonlinear mechanisms of wave growth and wave-wave interactions (WWI) in the magnetosphere. Three general classes of WWI (triggering, suppression, and entrainment) are identified and interpreted in terms of a model based on cyclotron resonance interaction. A new type of triggered emission, the ‘band-limited impulse’ (BLI), often appears at the end of an amplified signal. It covers a frequency range of about 150 Hz above the carrier. It is interpreted in terms of the switching of phase-bunched currents from their driven mode at the carrier frequency fo to their natural modes at fo + Δf where Δf depends on the change in medium parameters over the interaction region. In a related type of BLI, which appears before the termination of the amplified pulse, the frequencies are symmetrically distributed about the carrier. Assuming that this BLI is caused by wave-induced spread in the vM of the interacting electrons, the frequency range (± 100 Hz) of the BLI gives an estimate of the local values (~20 pT) of the wave field. Triggering and entrainment of self- sustained emissions are interpreted using the same model and their properties lead to independent estimates of signal strength (~1 pT) at the input to the interaction region (IR). Measured temporal growth typically ranges from 20–30 dB, giving output fields of 10–100 pT in the equatorial region at L = 4. It is estimated that a step function wave of this value can produce an initial pitch precipitation flux of ~0.1 ergs/cm2-sec for E≥1 keV through pitch angle scattering, sufficient to explain observed transient bursts of X-ray fluxes and E-region ionization enhancements.
Steady incompressible variable thickness shear layer aerodynamics

A shear flow aerodynamic theory for steady incompressible flows is presented for both the lifting and non lifting problems. The slow variation of the boundary layer thickness is considered. The slowly varying behavior is treated by using multitime scales. The analysis begins with the elementary wavy wall problem and, through Fourier superpositions over the wave number space, the shear flow equivalents to the aerodynamic transfer functions of classical potential flow are obtained. The aerodynamic transfer functions provide integral equations which relate the wall pressure and the upwash. Computational results are presented for the pressure distribution, the lift coefficient, and the center of pressure travel along a two dimensional flat plate in a shear flow. The aerodynamic load is decreased by the shear layer, compared to the potential flow. The variable thickness shear layer decreases it less than the uniform thickness shear layer based upon equal maximum shear layer thicknesses.
Generate, test and debug: combining associational rules and causal models

We present a problem solving paradigm called generate, test and debug (GTD) that combines associational rules and causal models, producing a system with both the efficiency of rules and the breadth of problem solving power of causal models. The generator uses associational rules to generate plausible hypotheses; the tester uses causal models to test the hypotheses and produce a detailed characterization of the discrepancy in case of failure. The debugger uses the ability to reason about the causal models, along with a body of domain-independent debugging knowledge, to determine how to repair the buggy hypotheses. The GTD paradigm has been implemented and tested in three different domains; we report in detail on its application to our principal domain of geologic interpretation. We also explore in some depth the character of the problems for which GTD is well suited and consider the character of the knowledge required for successful use of the paradigm.
Assessment of X Chromosome Dosage Compensation in Caenorhabditis elegans by Phenotypic Analysis of lin-14

Caenorhabditis elegans compensates for the difference in X chromosome gene dose between males (XO) and hermaphrodites (XX) through a mechanism that equalizes the levels of X-specific mRNA transcripts between the two sexes. We have devised a sensitive and quantitative genetic assay to measure perturbations in X chromosome gene expression caused by mutations that affect this process of dosage compensation. The assay is based on quantitating the precocious alae phenotype caused by a mutation that reduces but does not eliminate the function of the X-linked gene lin-14. We demonstrate that in diploid animals the lin-14 gene is dosage compensated between XO and XX animals. In XXX diploid animals, however, lin-14 expression is not compensated, implying that the normal dosage compensation mechanism in C. elegans lacks the capacity to compensate completely for the additional X chromosome in triplo-X animals. Using the lin-14 assay we compare the effects of mutations in the genes dpy-21, dpy-26, dpy-27, dpy-28, and dpy-22 on X-linked gene expression. Additionally, in the case of dpy-21 we correlate the change in phenotypic expression of lin-14 with a corresponding change in the lin-14 mRNA transcript level.
A randomized trial of controlled-release oxycodone during inpatient rehabilitation following unilateral total knee arthroplasty.

Background Reliance on "as-needed" analgesia following total knee arthroplasty may lead to inadequate control of pain and delayed recovery of function. Preemptive use of controlled-release opioids may improve pain control, accelerate recovery, and reduce the need for inpatient rehabilitative services. This study was designed to determine whether controlled-release opioids enhance post-arthroplasty pain control and facilitate functional recovery during rehabilitation. Methods Fifty-nine patients admitted for inpatient rehabilitation following unilateral total knee arthroplasty were randomized to receive OxyContin (controlled-release oxycodone) (twenty-nine patients) or a placebo (thirty patients) every twelve hours. Both groups could receive on-request, immediate-release oxycodone (5 mg every four hours). The dose of study medication was increased on the basis of the frequency of requests for immediate-release oxycodone. Measures of interest included pain ratings as determined with a visual-analog scale, changes in the range of motion of the knee and quadriceps strength, and improvements in selected Functional Independence Measure scores during the first eight physical therapy sessions. The duration of the hospital stay for rehabilitation also was compared between the two groups. Results Baseline demographic, clinical, and functional characteristics were similar between the OxyContin and placebo groups. Compared with the placebo group, the patients who received OxyContin reported significantly less pain as well as significantly greater range of motion of the knee (passive motion, p = 0.036; active motion, p Conclusions Preemptive use of controlled-release oxycodone during rehabilitation following total knee arthroplasty leads to improved pain control, more rapid functional recovery, and a reduced need for inpatient rehabilitative services.
Cruise ship market segmentation: a ‘non-traditional’ port case study

Market segmentation in the cruise ship industry is an essential tool for securing a favourable market share. A case study of a mid-sized vessel operating from a ‘non-traditional’ port provides insights of the demographic and socio-economic characteristics of a cruise population. The questionnaire also supports the logic for a strong local/regional marketing effort and validates the rationale for the provision of a cruise service from a ‘non-traditional’ port.
Evaluation and Treatment of Children with Primary Immune Deficiency in the Emergency Department

The potential for morbidity and mortality in an ill child with primary immune deficiency (PID) is extremely high. It is estimated that there are more than 500,000 cases of PID in the United States and an incidence of up to 1 in 2000 live births. Although the increased outpatient care of these patients necessitates a standardized approach to maximize emergent treatment, the diversity of these rare diseases and their potential infectious, autoimmune, and malignant sequelae complicate treatment guidelines. We present an overview of the clinical characteristics of primary immune deficiencies and then describe unique aspects of emergent care for these complex patients. Conservative management with empiric antimicrobials, early and aggressive surgical debridement of abscesses, and admission at a tertiary pediatric care center are often indicated. Familiarity with the clinical manifestations of PID and collaboration with a pediatric immunologist are prerequisites for optimal emergent care of these complex patients.
Experimental investigation of ablation efficiency and plasma expansion during femtosecond and nanosecond laser ablation of silicon

Femtosecond laser (Ti:sapphire, 100 fs pulse duration) ablation of silicon in air was compared with nanosecond laser (Nd:YAG, 3 ns pulse duration) ablation at ultraviolet wavelength (266 nm). Laser ablation efficiency was studied by measuring crater depth as a function of pulse number. For the same number of laser pulses, the fs-ablated crater was about two times deeper than the ns-crater. The temperature and electron number density of the laser-induced plasma were determined from spectroscopic measurements. The electron number density and temperature of fs-induced plasmas decreased faster than ns-induced plasmas due to different energy deposition mechanisms. Images of the laser-induced plasma were obtained with femtosecond time-resolved laser shadowgraph imaging. Plasma expansion in both the perpendicular and the lateral directions were compared.
Small-Angle Neutron Scattering from Nonuniformly Labeled Block Copolymers

An analytical expression for the scattering profiles from a disordered melt of symmetric, nonuniformly labeled A−B diblock copolymers is derived using the multicomponent random phase approximation. The expression is simple and contains one additional, temperature-independent constant that is a measure of the ensemble-averaged deviations of the scattering lengths of the two blocks from their mean values. The kind of nonuniformity considered here is a natural consequence of many of the popular synthetic routes used to obtain deuterium labeled block copolymers. Small-angle neutron-scattering experiments were conducted on a block copolymer obtained by saturating the double bonds of an anionically synthesized polydiene precursor with deuterium. The scattering data from our block copolymer in the disordered state are qualitatively inconsistent with all of the previously published theories on block copolymer thermodynamics. The data are, however, in quantitative agreement with the proposed expression. This enabl...
A study of influence of role modeling on students' attitude formation during their psychiatric rotation.

(1980). A Study of Influence of Role Modeling on Students' Attitude Formation During Their Psychiatric Rotation. Issues in Mental Health Nursing: Vol. 2, No. 4, pp. 51-59.
List scheduling of parallel tasks

We are concerned with nonreconfigurable nonpreemptive scheduling policies, i.e., once a task has been started, its scheduled parallelism cannot be changed, nor can the task be preempted.
Evaluation of Adsorbed Arsenic and Potential Contribution to Shallow Groundwater in Tulare Lake Bed Area, Tulare Basin, California

Elevated As concentrations in shallow groundwater in parts of the Tulare Basin, California, are a concern because of potential migration into deeper aquifers that could serve as a source of future drinking water. The objectives of this study were to evaluate adsorbed As and the potential contribution to groundwater using (i) isotopic dilution, (ii) successive extraction with an electrolyte solution resembling the pore-water chemical composition, and (iii) PO, exchange for As. Sediment samples collected from 2 to 4 m below land surface in the Tulare Lake bed area contained a total As concentration of 24 mg As kg -1 . Pore water extracted under hydraulic pressure contained a total As concentration of 590 μg As L -1 , which predominantly contained As as arsenate [As(V), 97%], a minor amount of arsenite [As(III), 3%], and non-detectable organic As. The isotopic dilution method [ 73 As(V) estimated that the concentration of adsorbed As(V) on the sediment was 5.7 mg As kg -1 at pH 8.5 and 6.7 mg As kg -1 at pH 7.5, respectively. Fourteen successive 24-h extractions with the artificial pore water released up to 57 to 61% of the adsorbed As(V) that was determined by isotopic dilution, indicating that only a portion of the adsorbed As could be released to groundwater. The phosphate-exchangeable As (0.1 M PO 4 , pH 8.5 or 7.5) was 63% of the isotopically exchangeable As(V). Thus, extraction of As by 0.1 M PO 4 at ambient pHs is recommended as a method to determine the potential amount of As(V) on sediments that could be released to the solution phase. The overall results indicated that adsorbed As could be a significant source of As to groundwater. However, other factors that affect As transport such as the leaching rate need to be considered.
A decomposition theory for matroids VII: analysis of minimal violation matrices

Abstract Let P be a matrix property that is defined for the matrices over GF(2) or GF(3), and that is maintained under submatrix taking, row and column permutations, scaling, and pivots, and when a row or column unit vector is adjoined. We propose a general matroid-based technique for investigating the minimal violation matrices of P. The problem of understanding these matrices is converted to a matroid problem involving a certain class of matroids that is closed under the taking of minors. Each matroid of the class has its elements labelled in a novel way. The use of these labels is crucial for the efficacy of the overall approach. We apply the method to the case where P is the property of regularity (a binary matrix is regular if it can be signed to become a totally unimodular real matrix). The method yields surprisingly simple and complete constructions for the following matrix classes, for which to-date no complete construction other than enumeration has been known: The minimal nonregular binary matrices, the minimal violation matrices of total unimodularity, the complement totally unimodular matrices, and the ternary matrices that are almost binary. In addition we construct a large subclass of balanced matrices none of which is totally unimodular.
Cytochrome c activation of CPP32‐like proteolysis plays a critical role in a Xenopus cell‐free apoptosis system

In a cell-free system based on Xenopus egg extracts, Bcl-2 blocks apoptotic activity by preventing cytochrome c release from mitochondria. We now describe in detail the crucial role of cytochrome c in this system. The mitochondrial fraction, when incubated with cytosol, releases cytochrome c. Cytochrome c in turn induces the activation of protease(s) resembling caspase-3 (CPP32), leading to downstream apoptotic events, including the cleavage of fodrin and lamin B1. CPP32-like protease activity plays an essential role in this system, as the caspase inhibitor, Ac-DEVD-CHO, strongly inhibited fodrin and lamin B1 cleavage, as well as nuclear morphology changes. Cytochrome c preparations from various vertebrate species, but not from Saccharomyces cerevisiae, were able to initiate all signs of apoptosis. Cytochrome c by itself was unable to process the precursor form of CPP32; the presence of cytosol was required. The electron transport activity of cytochrome c is not required for its pro-apoptotic function, as Cu- and Zn-substituted cytochrome c had strong pro-apoptotic activity, despite being redox-inactive. However, certain structural features of the molecule were required for this activity. Thus, in the Xenopus cell-free system, cytosol-dependent mitochondrial release of cytochrome c induces apoptosis by activating CPP32-like caspases, via unknown cytosolic factors.
Partitioned Nature, Privileged Knowledge: Community-Based Conservation in Tanzania

Community Based Conservation (CBC) has become the catch–all solution to the social and ecological problems plaguing traditional top–down, protectionist conservation approaches. CBC has been particularly popular throughout Africa as a way to gain local support for wildlife conservation measures that have previously excluded local people and their development needs. This article shows that, despite the rhetoric of devolution and participation associated with new CBC models, conservation planning in Tanzania remains a top–down endeavour, with communities and their specialized socio–ecological knowledge delegated to the margins. In addition to the difficulties associated with the transfer of power from state to community hands, CBC also poses complex challenges to the culture or institution of conservation. Using the example of the Tarangire–Manyara ecosystem, the author shows how local knowledge and the complexities of ecological processes challenge the conventional zone–based conservation models, and argues that the insights of local Maasai knowledge claims could better reflect the ecological and social goals of the new CBC rhetoric.
Porosity in silver-tin amalgams.

Porosity has been determined metallographically for a series of spherical silvertin amalgams. The alloy consisted of separate size fractions of five compositions. Porosity was found to increase with increasing silver content and particle size, and was reduced by blending of large and small particle sizes. In blended alloys the porosity showed close correlation to the observed setting expansion.
Methods for estimating on-site ambient air concentrations at disposal sites

Currently, Gaussian type dispersion modeling and point source approximation are combined to estimate the ambient air concentrations of pollutants dispersed downwind of an areawide emission source, using the approach of virtual point source approximation. This Gaussian dispersion modeling becomes less accurate as the receptor comes closer to the source, and becomes inapplicable for the estimation of on-site ambient air concentrations at disposal sites. Partial differential equations are solved with appropriate boundary conditions for use in estimating the on-site concentrations in the ambient air impacted by emissions from an area source such as land disposal sites. Two variations of solution techniques are presented, and their predictions are compared.
Studies related to the metabolism of anabolic steroids in the horse: The phase I and phase II biotransformation of 19-nortestosterone in the equine castrate

1. The metabolism of 19-nor[4-14C]testosterone has been studied in the equine castrate.2. Following XAD-2 extraction of aliquots of the 0—24 h urine samples, the glucuronic acid and sulphate conjugates were separated by Sephadex LH-20 column chromatography. After hydrolysis of the conjugates, the neutral phase I metabolites of 19-nortestosterone were extracted, purified and identified by g.l.c.-mass spectrometry.3. In phase I metabolism stereospecificity was observed in the reduction of the A-ring with the formation of the 5α,β-isomers of estranediol. Epimerization at C-17 and hydroxylation at C-16 were the other major pathways.4. In phase II metabolism the C-17α steroid epimers were predominantly conjugated with glucuronic acid and the C-17β epimers with sulphuric acid.5. One animal showed a slight variation in metabolism with a tendency towards the formation of polar metabolites.
Field Experiences in High-Need, Urban Settings: Analysis of Current Practice and Insights for Change

High-need urban districts face many challenges in their efforts to overcome the large gaps in achievement demonstrated by their students. This study focuses on a strategy to overcome these challenges by better preparing future teachers for service in urban schools through quality field experiences at these sites. Teacher educators and urban school teachers who host teacher candidates during field experiences completed a questionnaire regarding their views about placements in high-need urban districts. A thematic analysis of their responses summarizes their beliefs about the most and least beneficial forms of field experiences, the most prevalent challenges in establishing quality field experiences, and the most successful strategies that facilitate the development of quality field experiences. The discussion compares the views of teacher educators with practicing teachers and recommends strategies to enhance field experiences in high-need, urban schools.
Asymptotic behavior of Iwasawa and Cholesky iterations

Abstract We extend, in the context of a connected real semisimple Lie group, some results on the QR iteration and the Cholesky iteration of a nonsingular matrix. A group theoretic understanding of the abstract mechanisms of the iterations is obtained.
Nanostructured CoCu powders via a chemical route

Abstract Nanostructured CoCu powders were synthesized by coprecipitation of constituent metallic salts using aqueous sodium borohydride. As-synthesized powders showed a fcc structure and an amorphous phase. The amount of amorphous phase was found to increase with the ratio of Co/Cu. Upon annealing the as-synthesizedpowdersphaseseparated into nanocrystalline fcc Co and fcc Cu. Coercivity increased with annealing temperature and reached a maximum value at about 620 Oe, exhibiting the behavior of magnetic granular solids.
Dynamical behavior of the implant profile during ion implantation at elevated temperatures

The evolution of the implant distribution in time and space during elevated temperature ion implantation has been theoretically investigated using a comprehensive kinetic model. The implanted atoms were allowed to interact with the surface and with radiation-induced point defects. The synergistic effects of Gibbsian segregation, preferential sputtering, displacement mixing, radiation-enhanced diffusion, and radiation-induced segregation, as well as the influence of spatially nonuniform defect production were taken into account. The effects of the dynamical changes in the ion and damage distributions during implantation were also incorporated, by updating these distributions at high doses, using information obtained from TRIM calculations. Model calculations were performed for Al{sup +} and Si{sup +} implantation into Ni. 4 refs., 2 figs.
Physical Skill Training Increases the Number of Surviving New Cells in the Adult Hippocampus

The dentate gyrus is a major site of plasticity in the adult brain, giving rise to thousands of new neurons every day, through the process of adult neurogenesis. Although the majority of these cells die within two weeks of their birth, they can be rescued from death by various forms of learning. Successful acquisition of select types of associative and spatial memories increases the number of these cells that survive. Here, we investigated the possibility that an entirely different form of learning, physical skill learning, could rescue new hippocampal cells from death. To test this possibility, rats were trained with a physically-demanding and technically-difficult version of a rotarod procedure. Acquisition of the physical skill greatly increased the number of new hippocampal cells that survived. The number of surviving cells positively correlated with performance on the task. Only animals that successfully mastered the task retained the cells that would have otherwise died. Animals that failed to learn, and those that did not learn well did not retain any more cells than those that were untrained. Importantly, acute voluntary exercise in activity wheels did not increase the number of surviving cells. These data suggest that acquisition of a physical skill can increase the number of surviving hippocampal cells. Moreover, learning an easier version of the task did not increase cell survival. These results are consistent with previous reports revealing that learning only rescues new neurons from death when acquisition is sufficiently difficult to achieve. Finally, complete hippocampal lesions did not disrupt acquisition of this physical skill. Therefore, physical skill training that does not depend on the hippocampus can effectively increase the number of surviving cells in the adult hippocampus, the vast majority of which become mature neurons.
Minimally coupled N-particle scattering integral equations

A concise formalism is developed which permits the efficient representation and generalization of several known techniques for deriving connected-kernel $N$-particle scattering integral equations. The methods of Kouri, Levin, and Tobocman and Bencze and Redish which lead to minimally coupled integral equations are of special interest. The introduction of channel coupling arrays is characterized in a general manner and the common base of this technique and that of the so-called channel coupling scheme is clarified. It is found that in the Bencze-Redish formalism a particular coupling array ahs a crucial function but one different from that of the arrays employed by Kouri, Levin, and Tobocman. The apparent dependence of the proof of the minimality of the Bencze-Redish integral equations upon the form of the inhomogeneous term in these equations is eliminated. This is achieved by an investigation of the full (nonminimal) Bencze-Redish kernel. It is shown that the second power of this operator is connected, a result which is needed for the full applicability of the Bencze-Redish formalism. This is used to establish the relationship between the existence of solutions to the homogeneous form of the minimal equations and eigenvalues of the full Bencze-Redish kernel.[NUCLEAR REACTIONS Scattering theory, $N$-particle scattering, integral equations, channel coupling, array theory.]
Sleep protects memories from interference in older adults

In a recent study, we demonstrated that sleep-dependent consolidation of declarative memories is preserved in older adults. The present study examined whether this benefit of sleep for declarative learning in older adults reflects a passive role of sleep in protecting memories from decay or an active role in stabilizing them. Young and older adults learned a visuospatial task, and recall was probed after sleep or wake. Although a reduction in performance was observed after sleep and wake, task-related interference before recall had a larger detriment on performance in the wake condition. This was true for young and high performing older adults only. Low performing older adults did not receive a benefit of sleep on the visuospatial task. Performance changes were associated with early night nonrapid eye movement sleep in young adults and with early night rapid eye movement sleep in high performing older adults. These results demonstrate that performance benefits from sleep in older adults as a result of an active memory stabilization process; importantly, the extent of this benefit of sleep is closely linked to the level of initial acquisition of the episodic information in older adults.
Benefits Associated With Precepting Dietetic Interns and Preceptor Expectations

Abstract As health care expenses climb and administrators carefully analyze teaching commitments, supervised practice programs must be concerned with determining the benefits derived from services provided by dietetic interns. To facilitate student success and preceptor satisfaction preceptor's expectations of dietetic interns must be considered and identified. A total of fifty-five preceptors participated in this survey. Most of the respondents (64%) were registered dietitians. Others included certified executive chefs, foodservice managers, and extension home economists. All (100%) who participated in this study believed their departments either gained or broke even as a result of precepting interns. This study found that preceptors agreed that benefits existed for themselves and for the department. The estimated orientation and training time saved by hiring program graduates was a mean of three weeks (±1.8) per hire. The qualities preceptors expected from an intern entering an internship were motivation, professional behavior and communication skills. Those characteristics/behaviors which they believed hindered intern's success were the lack of motivation, communication skills, and poor attitude. The characteristics and/or behaviors they believed facilitate intern success are communication skills, taking initiative, flexibility and sound technical skills. Preceptors would advise interns to be flexible, exhibit positive personal behaviors, observe and take advantage of every learning situation, be proactive, and practice good communication skills in order to be successful in the internship. The effects of health care restructuring on the preceptor's role were an increase in their responsibilities and the need for interns to be better prepared. The need to demonstrate the benefits of dietetics education programs is vital to the continuation of dietetic programs. With the feedback and commitment of preceptors these benefits can be realized.