cssi/SciSciGPT-SciSciNet huggingface dataset:
Adaptations of the Reproductive System of Rodents to Changing Photoperiodic Conditions

All mammals which inhabit the temperate and polar regions of the earth are seasonal breeders. Thus, they are capable of successful reproduction for only a finite period of time each year. The fluctuation in reproductive competence ensures that the young are born during a very restricted period of time. Most commonly this is the spring and early summer. Mammals have evolved mechanisms to ensure seasonal breeding for a very specific reason, i.e., it increases the chances of survival for the young. The warm days of the spring and summer in combination with increased food availability at this time of the year promotes survival of the newborns. Mammals have evolved a variety of different mechanisms to ensure seasonal reproduction. Many of them depend on the changing environmental photoperiod as a predictor of the upcoming season. These species are described as being photoperiodic.
Pharmacological Treatment of Insomnia

The complaint of trouble sleeping is very common in the practice of sleep medicine, and every physician who wants to be known as a sleep specialist should be knowledgeable about insomnia and have an organized and systematic approach to this problem. It has been estimated that 9% of adults in the United States have a complaint of insomnia, although the prevalance may be as high as 22%. Patients with insomnia view their problem in very emotional terms and for them it is very serious. And when patients see improvement, they are very grateful patients. Additionally, a complaint of insomnia increases morbidity in the elderly, for reasons ranging from falls to coronary events. Utilization of health care resources is higher in patients with severe insomnia. Insomnia should be considered a serious complaint from the patient because of the associated impairment of psychosocial function and quality of life. Insomnia can impair daytime alertness, concentration, memory, and ability to carry out daily tasks.
High availability, scalable storage, dynamic peer networks: pick two

Peer-to-peer storage aims to build large-scale, reliable and available storage from many small-scale unreliable, low-availability distributed hosts. Data redundancy is the key to any data guarantees. However, preserving redundancy in the face of highly dynamic membership is costly. We use a simple resource usage model to measured behavior from the Gnutella file-sharing network to argue that large-scale cooperative storage is limited by likely dynamics and cross-system bandwidth -- not by local disk space. We examine some bandwidth optimization strategies like delayed response to failures, admission control, and load-shifting and find that they do not alter the basic problem. We conclude that when redundancy, data scale, and dynamics are all high, the needed cross-system bandwidth is unreasonable.
How a Church Opened Its Doors

The Ecclesiological Investigations International Research Network organized a major international conference at Georgetown University, Washington National Cathedral and Marymount University, in 2015, to commemorate the fiftieth anniversary of the conclusion of the Second Vatican Council. The council, one of the most important events in the history of the Roman Catholic Church, initiated a process of renewal, transition and openness that affected not only Catholics, but all Christians, adherents of other religions, and the secular world. The Washington conference received worldwide media attention, with highlights including keynote addresses by several cardinals, archbishops, and bishops as well as eminent scholars from a wide and diverse range of backgrounds in terms of geography and expertise alike. The first of three volumes emerging from this event explores the twentieth century context preceding the council, the legacy of Vatican II in relation to issues such as ethics, social justice, church-world dynamics and economic activity, and offers a series of explorations of women and the church in the context of the council. It also discusses the important topic of inculturation and engages a range of ecumenical readings of Vatican II as well as exploring the future of ecumenical engagement in light of Vatican II. The volume draws to a close with the groundbreaking address on the future of ecumenical dialogue and of unity among churches and the human family in wider terms, by Cardinal Walter Kasper.
Transcriptional networks in the human epididymis.

Background The epithelial lining of the human epididymis is critical for sperm maturation. This process requires distinct specialized functions in the head, body, and tail of the duct. These region-specific properties are maintained by distinct gene expression profiles which are governed by transcription factor networks, non-coding RNAs, and other factors. Materials and methods We used genome-wide protocols including DNase-seq, RNA-seq and ChIP-seq to characterize open (active) chromatin, the transcriptome and occupancy of specific transcription factors (TFs) respectively, in caput, corpus, and cauda segments of adult human epididymis tissue and primary human epididymis epithelial (HEE) cell cultures derived from them. RNA-seq following TF depletion or activation, combined with gene ontology analysis also determined TF targets. Results Among regional differentially expressed transcripts were epithelial-selective transcription factors (TFs), microRNAs, and antiviral response genes. Caput-enriched TFs included hepatocyte nuclear factor 1 (HNF1) and the androgen receptor (AR), both of which were also predicted to occupy cis-regulatory elements identified as open chromatin in HEE cells. HNF1 targets were identified genome-wide using ChIP-seq, in HEE cells. Next, siRNA-mediated depletion of HNF1 revealed a pivotal role for this TF in coordinating epithelial water and solute transport in caput epithelium. The importance of AR in HEE cells was shown by AR ChIP-seq, and by RNA-seq after synthetic androgen (R1881) treatment. AR has a distinct transcriptional program in the HEE cells and likely recruits different co-factors (RUNX1 and CEBPβ) in comparison to those used in prostate epithelium. Discussion and conclusion Our data identify many transcription factors that regulate the development and differentiation of HEE cells. Moreover, a comparison between immature and adult HEE cells showed key TFs in the transition to fully differentiated function of this epithelium. These data may help identify new targets to treat male infertility and have the potential to open new avenues for male contraception.
Molecular Regulation of the Xenopus Circadian Clock

The vertebrate retina must be able to respond to ambient light levels that range over ten to twelve orders of magnitude over the course of the 24 hour day. This incredibly wide range of sensitivity is the result of many adaptive mechanisms that occur within the retina at both the intra–and inter–cellular levels, including changes in visual sensitivity, rhythmic production of neuromodulators such as melatonin and dopamine, changes in synaptic structure and function, rhythms in turnover of photosensitive membrane and many others (for reviews, see 1, 2). Although many of these adaptive processes can be acutely affected by light, it is now clear that there is an endogenous retinal circadian clock controlling these responses in most (if not all) classes of vertebrates. These clocks maintain the correct temporal organization of the retina, allowing it to anticipate daily changes in light and to segregate certain processes (e.g. disk turnover) to the proper time of day. Disruption of this temporal organization may result in retinal dysfunction and degeneration 3,4.
Spatial Ecology of Re-introduced American Martens in the Northern Lower Peninsula of Michigan

American martens (Martes americana) in the northern Lower Peninsula of Michigan (NLP) represent a re-introduced and isolated population that is the southern-most distributed marten population in eastern North America. During 2005–2006 we conducted a radiotelemetry and track-survey study of martens in the NLP. We estimated home-range size and patterns of habitat use in order to develop a spatial model to predict distribution of marten habitat. Marten home ranges were comprised of more (>75%) upland deciduous and upland mixed forest compared to the landscape, which included ≤60% of these cover types. Within core areas, martens selected upland conifer stands. Our Penrose habitat model identified <25% of the NLP as primary marten habitat. Further, 70% of marten habitat patches were <1000 ha in size and were isolated by an average of 5.3 km (SE = 2.0). Our marten habitat model identifies focal areas for surveying and monitoring populations and sites for supplementation or re-introduction. Our model also highlights the need for managers to better coordinate active landscape-scale management of wildlife and forests to reduce fragmentation impacts on extant and reintroduced marten populations.
Astrobiology Graduate Conference: A 15 Year Retrospective

The 15th Astrobiology Graduate Conference (AbGradCon) was held at the University of Utah this past July. AbGradCon is a unique academic conference that is organized solely by early career scientists for other early career scientists. Every year, graduate students and postdocs gather to present their research through oral and poster presentations, take part in public outreach events, and gather informally to forge connections with their peers. This provides the opportunity to create and strengthen interdisciplinary and international networks between early career astrobiologists who will be leaders of such research in the years to come. Indeed, after 15 iterations, many of the alumni of the earliest AbGradCon meetings have gone on to become senior scientists and principal investigators. As organizers of the 2019 meeting, we feel that AbGradCon can serve as a robust model for other student-led meetings in any discipline. Here, we reflect upon the successful changes that have been implemented over the years, ...
Personal Income Taxation and College Major Choice: A Case Study of the 1986 Tax Reform Act:

This article evaluates whether changes in relative earnings across majors due to a federal tax reform are likely to affect college major choice. I first estimate the change in expected after-tax li...
Spuriously Elevated Cardiac Troponin in the Setting of Atypical Chest Pain Presentation: A Diagnostic Conundrum.

Abstract A 47-year-old woman presented with atypical chest pain and a troponin level of 30.15 ng/dl. A detailed diagnostic work-up did not detect an acute myocardial infarction but revealed the pre...
Ventricular Arrhythmias, Defibrillators, Sudden Cardiac Death and Syncope

Ventricular tachyarrhythmias have heterogeneous etiologies, clinical consequences, and treatment strategies. Distinguishing ventricular tachyarrhythmias from supraventricular tachycardia (SVT) with aberrancy clinically and on the surface electrocardiogram can be challenging, yet has substantial therapeutic implications. A wide body of randomized clinical trial data has emerged addressing the efficacy of implantable cardioverter defibrillators (ICDs) for the prevention of sudden cardiac death.
Abstract P212: Admission National Institutes of Health Stroke Scale Associated With Higher Rates of Post Stroke Depression Independent of Imaging Characteristics

Introduction: The etiology of post-stroke depression (PSD) is still not fully understood. It is well known that leukoaraiosis is associated with cognitive decline and depression, but currently uncl...
Toxoplasma gondii Extends the Life Span of Infected Human Neutrophils by Inducing Cytosolic PCNA and Blocking Activation of Apoptotic Caspases

ABSTRACT Toxoplasma gondii is an intracellular protozoan parasite that has the remarkable ability to infect and replicate in neutrophils, immune cells with an arsenal of antimicrobial effector mechanisms. We report that T. gondii infection extends the life span of primary human peripheral blood neutrophils by delaying spontaneous apoptosis, serum starvation-induced apoptosis, and tumor necrosis alpha (TNF-α)-mediated apoptosis. T. gondii blockade of apoptosis was associated with an inhibition of processing and activation of the apoptotic caspases caspase-8 and -3, decreased phosphatidylserine exposure on the plasma membrane, and reduced cell death. We performed a global transcriptome analysis of T. gondii-infected peripheral blood neutrophils using RNA sequencing (RNA-Seq) and identified gene expression changes associated with DNA replication and DNA repair pathways, which in mature neutrophils are indicative of changes in regulators of cell survival. Consistent with the RNA-Seq data, T. gondii infection upregulated transcript and protein expression of PCNA, which is found in the cytosol of human neutrophils, where it functions as a key inhibitor of apoptotic pro-caspases. Infection of neutrophils resulted in increased interaction of PCNA with pro-caspase-3. Inhibition of this interaction with an AlkB homologue 2 PCNA-interacting motif (APIM) peptide reversed the infection-induced delay in cell death. Taken together, these findings indicate a novel strategy by which T. gondii manipulates cell life span in primary human neutrophils, which may allow the parasite to maintain an intracellular replicative niche and avoid immune clearance. IMPORTANCEToxoplasma gondii is an obligate intracellular parasite that can cause life-threatening disease in immunocompromised individuals and in the developing fetus. Interestingly, T. gondii has evolved strategies to successfully manipulate the host immune system to establish a productive infection and evade host defense mechanisms. Although it is well documented that neutrophils are mobilized during acute T. gondii infection and infiltrate the site of infection, these cells can also be actively infected by T. gondii and serve as a replicative niche for the parasite. However, there is a limited understanding of the molecular processes occurring within T. gondii-infected neutrophils. This study reveals that T. gondii extends the life span of human neutrophils by inducing the expression of PCNA, which prevents activation of apoptotic caspases, thus delaying apoptosis. This strategy may allow the parasite to preserve its replicative intracellular niche.
Crop and Semi-Natural Habitat Configuration Affects Diversity and Abundance of Native Bees (Hymenoptera: Anthophila) in a Large-Field Cotton Agroecosystem

The cotton agroecosystem is one of the most intensely managed, economically and culturally important fiber crops worldwide, including in the United States of America (U.S.), China, India, Pakistan, and Brazil. The composition and configuration of crop species and semi-natural habitat can have significant effects on ecosystem services such as pollination. Here, we investigated the local-scale effect of crop and semi-natural habitat configuration in a large field (>200 ha in size) cotton agroecosystem on the diversity and abundance of native bees. The interfaces sampled included cotton grown next to cotton, sorghum or semi-natural habitat along with a natural habitat comparator. Collections of native bees across interface types revealed 32 species in 13 genera across 3 families. Average species richness metrics ranged between 20.5 and 30.5, with the highest (30.5) at the interface of cotton and semi-natural habitat. The most abundant species was Melissodes tepaneca Cresson (>4000 individuals, ~75% of bees collected) with a higher number of individuals found in all cotton–crop interfaces compared to the cotton interface with semi-natural habitat or natural habitat alone. It was also found that interface type had a significant effect on the native bee communities. Communities of native bees in the cotton–crop interfaces tended to be more consistent in species richness and abundance. While cotton grown next to semi-natural habitat had higher species richness, the number of bees collected varied. These data suggest that native bee communities persist in large-field cotton agroecosystems. Selected species dominate (i.e., M. tepaneca) and thrive in this large-field cotton system where cotton–crop interfaces are key local landscape features. These data have implications for potential pollination benefits to cotton production. The findings also contribute to a discussion regarding the role of large-field commercial cotton growing systems in conserving native bees.
Interaction of Debt Agency Problems and Optimal Capital Structure: Theory and Evidence

Does more leverage always worsen the debt agency problem? This paper presents a unified analysis that accounts for both risk-shifting and under-investment debt agency problems. For firms with positive marginal volatility of investment (defined as the change in cash flow volatility corresponding to a change of investment scale), equity holders' risk-shifting incentive will mitigate the under-investment problem. This implies that, contrary to conventional views, the total agency cost of debt does not uniformly increase with leverage. This model further predicts that, for high growth firms in which the under-investment problem is severe, the optimal debt ratio is positively related to the marginal volatility of investment. Empirical results support this prediction.
You are what you eat: How and when workplace healthy eating cultivates coworker perceptions and behaviors.

Food consumption has been conceptualized as an integral aspect of employee well-being. Whereas most research in the organizational literature to date is motivated by individual health outcomes, we assert that eating at work also entails interpersonal implications. In this manuscript, we draw from consumption stereotype theory and suggest that workplace healthy eating affects how employees are perceived and treated at work. Specifically, we posit that workplace healthy eating influences the extent to which a focal employee is attributed the trait of self-control, which subsequently impacts coworker citizenship behavior and social undermining enacted toward the focal employee. Moreover, we postulate healthy eating climate as a boundary condition to the effects of workplace healthy eating-when there is a salient healthy eating climate, workplace healthy eating is a weaker signal in the trait attribution process. Overall, we extend the concept of employee eating to the interpersonal level by explaining how employee eating directly affects coworker interactions. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
High Precision Zero-friction Magnetic Dendrometer

Abstract Increasing agricultural demand for freshwater in the face of a changing climate requires improved irrigation management to maximize resource efficiency. Soil water deficits can significantly reduce plant growth and development, directly impacting crop quantity and quality. Dendrometers are a plant-based tool that have shown potential to improve irrigation management in high-value woody perennial crops (e.g., trees and vines). A dendrometer continuously measures small fluctuations in stem diameter; this has been directly correlated to water stress measurements using traditional methods. While plant-based measures of water deficits are considered to be the best measures of water stress, current dendrometer methods are imprecise due to mechanical hysteresis and thermal expansion. The high-precision dendrometer created at the OPEnS Lab alleviates these key failure points using zero-thermal expansion carbon fiber, zero friction via a spring tensioning approach, and a linear magnetic encoder. In-lab tests and field deployments have validated device measurements and the execution of these pivotal qualities. Mass deployment of these automated dendrometers has the potential to provide a continuous record of water stress, providing valuable decision support for irrigation management.
Denial and Reality Testing

In the last chapter, I introduced some of the ethical considerations involved in the common human response to medical information—denial and reality testing. In this chapter, I would like to go into this in more depth; but first, an explanation is probably owed the reader who is wondering why the concentration on such issues when most of the literature of medical ethics deals with abortion, passive euthanasia, compulsory sterilization, compulsory screening, and eugenics. My experience in a genetics clinic has been that such issues are not the real issues that arise with any degree of frequency in such a medical program. The routine ethical concerns instead center around such management issues as denial and reality testing, and around the value to the patient’s life of the genetic information available. I will discuss abortion as one of the options available in reproductive decision-making in some detail in a later chapter, and will touch on each of the other issues to some extent. But the bread-and-butter medical ethics issues, as they present themselves in actual cases, are in a sense more mundane, and in another sense, much more significant, than this. They consist of the physician/patient interaction and the justification for the routine interventions comprising that interaction. They are less glamorous, but decidedly more human.
Web-Based Teaching and Learning across Culture and Age

Preface.- Part I Diversity in Online Learning Contexts.- 1.Introduction and Background.- 2.Multicultural and Intergenerational Teaching and Learning: Current Research.- 3.A Two-Year Research Project on Web-Based Teaching and Learning.- Part II Study Findings.- 4.Diversity in Online Learning Interaction and Participation.- 5.Cultural Constructs in Teaching and Learning.- 6.Online Interaction and Learning Contexts Design and Learner Success.- Part III Designing for Success in Online Learning Contexts.- 7.Inclusive Design of Online Teaching and Learning.- 8.Promoting Inclusive, Deep Learning in Online Contexts.- 9.Concluding Thoughts on Web-Based Teaching and Learning across Culture and Age.
Development of a Laser Line Scan LIDAR Imaging System for AUV Use

Abstract : Our overall goal is to develop a next generation underwater optical imaging system for deployment on an Autonomous Underwater Vehicle. The system is predicted to have extended range performance ( 3 total attenuation lengths). This project is an extension of work that was initiated after the successful outcome of SBIR Phase I and II [topic N04-176, Aculight] programs that demonstrated that a new type of fiber laser could be developed that would fulfill the necessary role in a next generation underwater Laser Line Scan System for deployment on an AUV. Here, funds have been allocated to build two underwater pods that are suitable for inclusion deployment on Autonomous Underwater Vehicles. Here, we describe work accomplished during the period October 1, 20010 August 31, 2011. During this period, the project has progressed as we (Lockheed Martin Aculight, LMA, and SIO) have designed, built, and tested the hardware optical and electronic components for the final system. System tests by LMA have confirmed that the performance of the final configuration optical components will meet system specification goals. SIO supervised the assembly and delivery to LMA of the system chassis. Work with the Metron Corporation has also been collaboratively progressing as they have been working towards the creation of a model to predict system performance. As a result of choice of the Hydroid Remus 600 vehicle for our deployment platform and have been working with Hydroid to prescribe both the system s package and its incorporation into the Hydroid Remus 600 vehicle. This information has been incorporated into our expansion proposal to integrate the system into the Hydroid vehicle. We categorize our planned work as Phase III of a three-phase development. The jointly developed end product from Phase II is a laser imager that SIO will integrate into the Hydroid Remus 600 Vehicle AUV for at-sea testing.
An Experimental Study on the Stability of Superplastic Deformation of AZ31 Mg Alloy

Optimum variable strain rate forming paths based on two different multiscale deformation‐based stability criteria were developed. These criteria account for both geometrical necking (macroscopic feature) and microstructural evolution. In the first criterion, we defined the onset of instability using Hart’s stability analysis, where a linear perturbation in a small region along the tensile specimen is introduced. In the second criterion, we introduced a modified one dimensional nonlinear long wavelength analysis, based on the one introduced by Hutchinson and Neale. The two stability criteria are calibrated for the AZ31 magnesium alloy at 400 °C, yielding two different variable strain rate forming paths. Uniaxial tensile tests are carried out following the derived forming paths to examine the validity of both criteria. Results show that the linear approach underestimates the amount of uniform deformation, and therefore prolongs the forming time to prevent failure compared to the nonlinear analysis.
Pseudomonas aeruginosa High-Level Resistance to Polymyxins and Other Antimicrobial Peptides Requires cprA, a Gene That Is Disrupted in the PAO1 Strain

ABSTRACT The arn locus, found in many Gram-negative bacterial pathogens, mediates resistance to polymyxins and other cationic antimicrobial peptides through 4-amino-l-arabinose modification of the lipid A moiety of lipopolysaccharide. In Pseudomonas aeruginosa, several two-component regulatory systems (TCSs) control the arn locus, which is necessary but not sufficient for these resistance phenotypes. A previous transposon mutagenesis screen to identify additional polymyxin resistance genes that these systems regulate implicated an open reading frame designated PA1559 in the genome of the P. aeruginosa PAO1 strain. Resequencing of this chromosomal region and bioinformatics analysis for a variety of P. aeruginosa strains revealed that in the sequenced PAO1 strain, a guanine deletion at the end of PA1559 results in a frameshift and truncation of a full-length open reading frame that also encompasses PA1560 in non-PAO1 strains, such as P. aeruginosa PAK. Deletion analysis in the PAK strain showed that this full-length open reading frame, designated cprA , is necessary for polymyxin resistance conferred by activating mutations in the PhoPQ, PmrAB, and CprRS TCSs. The cprA gene was also required for PmrAB-mediated resistance to other cationic antimicrobial peptides in the PAK strain. Repair of the mutated cprA allele in the PAO1 strain restored polymyxin resistance conferred by an activating TCS mutation. The deletion of cprA did not affect the arn -mediated lipid A modification, indicating that the CprA protein is necessary for a different aspect of polymyxin resistance. This protein has a domain structure with a strong similarity to the extended short-chain dehydrogenase/reductase family that comprises isomerases, lyases, and oxidoreductases. These results suggest a new avenue through which to pursue targeted inhibition of polymyxin resistance.
Z-source Dc circuit breakers with coupled inductors

This paper considers design details of the z-source breaker. Specifically, the effect of coupled inductors on the z-source breaker is studied. It is shown that the inductor weight can be reduced by 30% and the inductor volume can be reduced by about 25% when coupled inductors are used. Furthermore, the coupling plays a part in the commutation process meaning that the breaker can operate with one capacitor instead of two. These results mean that the major components of the z-source breaker can be greatly reduced. Simulations are carried out to verify the results.
Discussion of “Executive stock-based compensation and firms’ cash payout: the role of shareholders’ tax-related payout preferences”

Aboody and Kasznik (Rev Acc Stud, this issue, 2008) develop and test cross-sectional predictions about how firms might respond to the 2003 dividend tax cuts. My discussion suggests some alternative firm responses, a restructuring of the main tests to be consistent with the theory and predictions, and an interpretation of the magnitude of the observed associations. Overall, the paper addresses an interesting issue, recognizes that executive compensation is endogenous in this event, and adds to the long literature on dividend payout policy.
Growth factor and bcl-2 mediated survival during abortive proliferation of hybridoma cell line.

Cultures of the CRL-1606 hybridoma (ATCC) have been reported to undergo continuous proliferation with simultaneous death during nutrient limited fed-batch fermentations. The bcl-2 proto-oncogene has been shown to prevent cell death under a variety of otherwise death inducing conditions. We were interested in elucidating the nature of the massive death observed in cultures of CRL-1606, specifically with respect to the possible environmental causes, and the ability of overexpressed human bcl-2 (h bcl-2) to mitigate cell death. Abortive proliferation, or continuous proliferation in the presence of continuous death, could be induced in serum free cultures of CRL-1606 through the withdrawal of insulin provided the culture was competent for cell proliferation. Culture competency for proliferation was found to be solely determined by the presence of cell culture nutrients. Abortive proliferation was defective in cultures transfected with h bcl-2 and the enhanced viability observed resulted from an increased viable cell population and at the expense of the nonviable cell population normally found in untransfected cultures. Abortive proliferation was also observed in serum containing cultures upon serum shiftdowns. Like the insulin-supplemented serum free culture system, h bcl-2 transfected cultures exhibited defects in the abortive proliferation process. These results suggest that the massive death observed during nutrient-limited fed-batch fermentation originate, in part, from growth or survival factor limitations. Hence, approaches to design cell culture media that account for the cell's proliferation requirements without accounting for the cell's survival requirements may represent a cell death sentence. Given the transformed nature of the hybridomas, we conclude that the abortive proliferation of CRL-1606 is a consequence of inappropriate cell cycle entry in a survival factor limited environment.
Ultrastructural aspects of the neurohypophysis of the white-crowned sparrow, Zonotrichia leucophrys gambelii, with special reference to the relation of neurosecretory axons to ependyma in the pars nervosa ☆

Abstract Several ultrastructural features of the neurohypophysis, as yet undescribed in birds, were examined in the white-crowned sparrow. Within the pars nervosa are structures that superficially resemble blood capillaries. However, further study shows that these structures are the attenuated branches of the infundibular recess. The relation of neurosecretion-bearing axons to these extensions of the ventricle differs from that to blood capillaries in the following respects: (1) absence of a basement membrane region; (2) absence of a glial layer between the axons and the ependyma; and (3) greater thickness of the ependyma as compared with the capillary endothelium. In addition to elementary neurosecretory granules and vesicles, small vesicles occur in axon endings adjacent both to blood capillaries and ventricular diverticula; they tend to be more concentrated on the side of the axon adjacent to a diverticulum. Possible release of neurohypophysial hormones into the cerebrospinal fluid is considered. Large clefts of unknown significance, not limited by an epithelium and not ventricle-connected, are present in the median eminence.
The associations between immigrant status and risk-behavior patterns in Latino adolescents

Purpose: The purpose of this study was to identify differences in patterns of risk-taking behavior among Latino adolescents with respect to immigrant status and in comparison to their native non-Hispanic white counterparts. Methods: In fall of 1988 and spring of 1989 a confidential Teen Health Risk Survey was administered to 1,789 students at two high schools in northern California, both of which have a school health center on-site, and which had large numbers of Latino students enrolled. We divided the Latino adolescent population into two groups: Latinos who were born in the United States ( native-born Latinos) and Latinos who had immigrated to the United States (Latino immigrants ). Eight different risk-taking behaviors were identified for this study: alcohol, cigarette, marijuana, illicit drug use, self-violence, drunk driving, unintended pregnancy, and violence. Results: We found that in general, Latino students engaged in a greater number of risk-taking behaviors than native non-Hispanic whites. The mean number of risk behaviors was highest for Latino immigrants (1.78), followed by native-born Latinos (1.71), and native non-Hispanic whites (.99). A t-test revealed that non-Hispanic whites were statistically different from both Latino populations in their level of risk-taking behavior (p Conclusions: This sample of immigrant Latino students appeared to be vulnerable to engaging in risk-taking behaviors and did not exhibit the anticipated cultural protective factors associated with recent immigrants. The extent and variety of risk-taking behaviors clearly call for the development of culturally sensitive and accessible health education and health care services within a broader array of social, educational and support services.
Student Spirituality and School Counseling: Issues, Opportunities, and Challenges

In this article, the professional school counseling community is introduced to the value of addressing student spirituality as a way to foster personal and social growth. Prior to discussing the robust theoretical and research foundation for this endeavor, 3 workable definitional strands of spirituality are summarized and applied to educational settings. Strategies for transitioning from the conceptual to school practice are explored, including the key issues related to legal and ethical practice and school counselor education and training. Finally, recommendations for future school counseling research in this area are briefly examined.
Controlled/Living Radical Polymerization of tert-Butyl Acrylate Mediated by Chiral Nitroxides. A Stereochemical Study

The two diastereomeric alkoxyamines of tBP-DEPN, where tBP is 1-(tert-butoxycarbonyl)ethyl and DEPN is N-(2-methylpropyl)-N-(1-diethylphosphophono-2,2-dimethylpropyl)aminoxyl, have marked differences in their thermodynamic stability (ratio of diastereomers is 5:1 at 100 °C in o-dichlorobenzene). They were used as initiators for the controlled/living radical polymerization of tert-butyl acrylate to test the premise that such moderators could potentially affect the tacticity of the resulting poly(tert-butyl acrylate). 2D NMR was used to analyze the end group configuration for the samples with shorter chain lengths (DPn = 15−20). Although the diastereomeric excess in the polymer alkoxyamine end group is even higher than for the model compound (ratio of diastereomers is 7:1), the distribution of terminal triads in poly(tert-butyl acrylate) does not differ from those in the entire chain and is identical to that of the polymers prepared by ATRP. Thus, the tacticities of the poly(tert-butyl acrylate)s prepared b...
Reaction of nitrogen dioxide with polystyrene films

The reaction of nitrogen dioxide with thin polystyrene films has been investigated at 35°C with different partial pressures of NO2 (0.1, 2, 15, 30, and 60 cm Hg) and at several temperatures (25, 35, 45 and 55°C). The films were thin enough (ca. 20 μ) so that the reaction was independent of the diffusion of gas into the polymer. The experimental results can be represented by a chain mechanism. The whole degradation process is controlled by the diffusion of polymer radicals out of cages. This diffusion in turn, is affected by the decrease in viscosity or decrease in weight-average molecular weight as degradation proceeds. This leads to an acceleration of the degradation process. A straight-line relationship between the logarithm of the reciprocal weight-average molecular weight and the logarithm of a reaction–time function was found. The dependence on the rate was substantiated by degrading polymer fractions. The energy of activation for the process is small, in agreement with a diffusion process for chain scission. Nitro and nitrite groups are incorporated along the backbone of polystyrene during exposure. The number of these polar side groups appears to pass through a maximum with time, as is evidenced by aggregation of polymer molecules in benzene solution only during the middle stage of the degradation. The final stage of the process is slowed down by retarder being produced. This retarder can be removed by reprecipitation of exposed polymer films. Degradation in solution is similar to that of films. Isotactic polystyrene shows less irregularities in its degradation curve than the atactic polymer. This is, presumably, due to its more homogeneous morphology, large molecular weight, and broader molecular size distribution. The plot of the degree of degradation versus time for the isotactic polymer can be satisfactorily approximated by a straight line.
Does Delayed Childbearing Increase Risk

To the Editor. —The findings by Cnattingius et al1of increased risks of adverse perinatal outcomes with advancing maternal age in a population-based study of Swedish nulliparous women contrast with the results of our hospital-based study in the United States.2The authors suggest that our findings are only characteristic of the population we studied, but that their results have ramifications for the United States. We take issue with this suggestion as there may be important cross-national differences that bear on the contrasting findings. Our study population comprised private patients who were predominantly white, married, college-educated, nonsmoking, and healthy. While we emphasized that our findings may not be generalizable to other sociodemographic groups, we also noted that this study population probably typifies urban women in the United States who postpone childbearing. According to a recent national report,349% of nulliparous women 30 years or older were college graduates.
Mixture experiments with process variables: D-optimal orthogonal experimental designs

Blending experiments with mixture in the presence of process variables are considered. We present an experimental design for quadratic (or linear) blending. The design in two orthogonal blocks is D-optimized in the case where there are no restrictions on the blending in two orthogonal blocks is presented when there are arbitrary restrictions on the blending components. The pair of orthogonal blocks can be used with and arbitrary number of process variables. The number of design points needed when different orthogonal blocks are used is usually smaller than when a single block is repeated at the various process variables levels.
Computer-generated character tables and nuclear spin statistical weights: application to benzene dimer and methane dimer

A short GAP computer program is presented for computing nuclear spin statistical weights of rovibronic symmetry species in polyatomic molecules. As examples, benzene dimer and methane dimer are discussed.
Intracranial Collateral Anastomoses: Relevance to Endovascular Procedures

An in-depth knowledge of intracranial and extracranial collateral anastomoses, overt or hidden, is crucial for an interventionist to devise optimal endovascular strategies to manage a host of pathologic conditions; to ascertain potential pitfalls; and, ultimately, to avoid complications that could have been prevented by a better understanding of underlying vascular anatomy. As the scope and extent of endovascular interventions for cerebrovascular and cranial disease continues to expand, the recognition of these putative anastomoses will continue to become a larger part of diagnostic evaluation and interventional design. This article provides a brief overview of cranial vascular development, followed by specific clinically relevant examples of extracranial and intracranial anastomoses and the internal carotid artery and vertebrobasilar anastomoses.
Effect of intravenous lactated Ringer's solution infusion on the circulating lactate concentration: Part 3. Results of a prospective, randomized, double-blind, placebo-controlled trial

Objectives We prevlously discovered that small amounts of lactated Ringer's solution, which are inadequately cleared from an intravenous catheter, falsely increase the circulating lactate concentration in blood samples collected from that catheter. That finding prompted us to test the hypothesis tha
Hadron collider physics at Fermilab

Abstract The hadron collider physics program at Fermilab, Tevatron-I, has recently provided considerable data samples to two high beta experiments as well as one low beta general purpose Collider Detector at Fermilab (CDF). A brief description of the Tevatron collider and the high beta experiments is followed by a discussion of hard scattering results from CDF. The prospects for growth in this exciting physics program are outlined.
Intellectual assessment of young children with environmentally based failure to thrive

Abstract Objective assessment of intellectual development has an important role in diagnosis and treatment of infants and young children with environmentally based failure to thrive. Clinical experiences in a pediatric hospital are presented which illustrate the way intellectual assessment can be used to diagnose the impact of deprivation, aid parent-infant interaction, suggest strategies for remediation and assess the therapeutic effectiveness of environmental change. Repeated intellectual assessments provide an objective means of gauging the effectiveness of treatment during hospitalization and follow up periods. Since many infants who fail to thrive initially present with behavioral deficits which can affect their test performance, intellectual assessment of these children should involve careful observation of their social responsiveness and approach to test materials. Analysis of the patterns of the child's intellectual strengths and deficits is much more helpful for treatment planning than global intelligence level alone. In addition, parental observation of the testing, particularly if accompanied by sensitive explanation from the examiner, can help familiarize parents with their child's abilities and deficits. Optimal utilization of psychological assessment on a pediatric inpatient service requires a high level of psychologist visibility to sensitize staff to the potential importance of cognitive assessment in the treatment planning. Weekly teaching rounds in which the staff observes intellectual assessment of children who fail to thrive provide a useful means of facilitating the close interdisciplinary collaboration so necessary for effective treatment of this difficult problem.
Saliva increases serum IgG retention on Streptococcus mutans.

The purpose of this investigation was to determine if saliva would affect the retention of serum antibodies to S. mutans. A quantitative enzyme-linked immunosorbent assay (ELISA) was used to estimate total IgM, IgG and IgA after applications of whole saliva and absorbed serum to equal but separate aliquots of S. mutans. Total antibodies were also estimated after the sequential application of saliva and adsorbed serum to the same aliquot of S. mutans. Significantly more IgG, but not IgM or IgA, was retained on saliva-treated cells than on untreated cells. IgG retention was greatly diminished when saliva was pre-ab-sorbed with S. mutans but Streptococcus sanguis was less effective. Most subjects, regardless of caries experience, had IgG that would be retained by saliva-treated cells but saliva from caries-resistant subjects promoted IgG retention significantly more than saliva from susceptible subjects.
Learning to see: the development of race and class consciousness in white teachers

This is a study of White teachers and their identity development. Using a qualitative approach steeped in the tenants of critical race theory and storytelling, this study investigated how White teachers learn about race, class and diversity in meaningful ways, with a close eye on the role their own personal histories played in their development. To better understand this phenomenon, three White teachers – all believed to be exceptionally skilled in educating children of color in urban centers – were interviewed over the course of several meetings. Their data provides insights into the factors and experiences that shape the race and class consciousness of successful White teachers in urban schools. Through the teachers’ stories, we glean an awareness of the salient life experiences that help build solidarity between students and teachers, help White teachers understand their own racial positioning, and illuminate ways in which teacher education programs can broaden their understanding of ‘quality’ teachers.
Technique for office-based, ultrasonography-guided percutaneous biopsy of renal cortical neoplasms using a novel transducer for facilitated ultrasound targeting

Objectives To help clarify which small renal cortical neoplasms (RCNs) require surgery by using office-based, ultrasonography-guided percutaneous renal biopsy. Patients and methods Biopsies were performed using facilitated ultrasound targeting (FUT) technology, which incorporates a needle guide and onscreen beam-steered technology to permit highly precise needle deployment. Patient and tumour characteristics, procedure time, complications and biopsy efficacy were documented. Wong-Baker pain levels were obtained before, during and 1 h after the procedure. Results Seven patients underwent biopsy, six for RCNs and one for medical renal disease. The mean (range) patient age was 68.5 (54-79) years, and the mean (range) tumour diameter was 2.55 (2.0-2.9) cm. Mean pain levels before, during and 1 h after the procedure were 0, 1.6 and 0.5, respectively. There were no intra- or post-procedural complications. Biopsy results were diagnostic in five of the six RCN cases and in the single case of medical renal disease. Conclusions Our preliminary experience shows that office-based percutaneous renal biopsy using a novel transducer for FUT is safe and effective. An international multicentre study is planned to confirm these preliminary results.
Rapid adenoviral neutralization assay

Pre-existing Neutralizing antibody (nab) to adenoviral vectors is one of the major limitations to the successful application of the vector in gene Therapy. Assaying for the presence of Neutralizing antibody becomes necessary for priming and also boosting treatment using adenoviral based regimen. Convectional Neutralization assay relies on the inhibition of cytopathic effect (CPE). This takes between 4 to 7 days and has occasionally proved unreliable. A quick and reliable assay is therefore desirable to overcome this hurdle.
Theoretical and experimental operating characteristics of a pneumatic gas chromatographic detector

Abstract The operation of an orifice-capillary combination as a detector for gas chromatography is examined in detail. Experimental results are compared to those predicted from a computer model of the system.