cssi/SciSciGPT-SciSciNet huggingface dataset:
Physical Activity and Sedentary Behavior among US Hispanic/Latino Youth: The SOL Youth Study.

Purpose Physical activity and sedentary behavior among diverse Hispanic/Latino youth in the United States is not well documented. The aim of this study was to describe physical activity and sedentary behavior among a representative sample of Hispanic/Latino youth from four US communities using accelerometry and self-reported measures. Methods From 2012 to 2014, 1466 Hispanic/Latino youth ages 8 to 16 yr, children of participants in the Hispanic Community Health Study/Study of Latinos, enrolled in the SOL youth. Physical activity and sedentary behavior were assessed by interview. After this, youth wore an Actical accelerometer for 1 wk. All statistical analyses accounted for the complex survey design and used sampling weights. Results The accelerometer wear time adjusted mean minutes per day was: 604.6, sedentary; 178.9, light; 25.4, moderate; and 10.2, vigorous. Generally, higher levels of moderate and vigorous activity occurred among males, Mexican backgrounds, and youth age 8 to 10 yr compared with older age groups. Higher levels of sedentary behavior occurred among youth age 15 to 16 yr compared with younger age groups. The most common activities (reported, ≥1 per month) were of lower intensity, including listening to music (91.9%), homework (87.0%), riding in car/bus (84.3%), and hanging out with friends (83.4%). Common active pursuits included travel by walking (74.6%), physical education class (71.7%), running (71.4%), and recess (71.3%). Conclusions Time, intensity, and type of physical activity and sedentary behavior varied among Hispanic/Latino youth. These findings can inform efforts to increase physical activity and reduce sedentary behavior among US Hispanic/Latino youth.
Spatially Heterogeneous Ecosystems: Pattern Formation

No curious person can look out over the valley of a river or stream without wondering at the obstinate refusal of the water to flow in a straight line from higher to lower ground, even when the terrain is gentle enough to allow it the opportunity. Instead, the river meanders, snake-like down the valley. This phenomenon is so counterintuitive that the nineteenth century sociologist Lester Ward offered it as an example of nature’s wastefulness of energy (see Worster, 1977, p. 175).
FDG PET based prediction of response in head and neck cancer treatment: Assessment of new quantitative imaging features

Introduction 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET) is now a standard diagnostic imaging test performed in patients with head and neck cancer for staging, re-staging, radiotherapy planning, and outcome assessment. Currently, quantitative analysis of FDG PET scans is limited to simple metrics like maximum standardized uptake value, metabolic tumor volume, or total lesion glycolysis, which have limited predictive value. The goal of this work was to assess the predictive potential of new (i.e., nonstandard) quantitative imaging features on head and neck cancer outcome. Methods This retrospective study analyzed fifty-eight pre- and post-treatment FDG PET scans of patients with head and neck squamous cell cancer to calculate five standard and seventeen new features at baseline and post-treatment. Cox survival regression was used to assess the predictive potential of each quantitative imaging feature on disease-free survival. Results Analysis showed that the post-treatment change of the average tracer uptake in the rim background region immediately adjacent to the tumor normalized by uptake in the liver represents a novel PET feature that is associated with disease-free survival (HR 1.95; 95% CI 1.27, 2.99) and has good discriminative performance (c index 0.791). Conclusion The reported findings define a promising new direction for quantitative imaging biomarker research in head and neck squamous cell cancer and highlight the potential role of new radiomics features in oncology decision making as part of precision medicine.
The graying of the flock revisited

Twenty years have passed since a national study was conducted that examined how congregations within the Churches of Christ were responding to their senior adult members. The present study sought t...
Continuous-Time Volatility Regression in Large Panels

This paper studies a semiparametric inference procedure for a finite-dimensional parameter in a continuous-time regression model involving high-frequency data in a large cross-section. The model concerns the relationship between a noisy dependent process and a possibly nonlinear transform of stochastic volatility over a fixed time span, with its coefficients allowed to depend on a set of firm-specific characteristics. The construction of the estimator involves two steps: the nonparametric recovery of stochastic volatility processes, followed by a parametric second stage that uses the volatility estimates. I show that the estimator admits a central limit theorem and provide a consistent estimator of the asymptotic variance based on a factor-analytic method. The finite sample performance of the inference procedure is satisfactory in a realistically calibrated Monte Carlo setting. In a novel empirical application, I study the relationship between bid-ask spread and the spot standard deviation of asset price. The slope coefficient estimate, which measures the heterogeneous level of information asymmetry, is closely related to firm characteristics such as measures of valuation uncertainty and institutional ownership.
Government Policy on Distribution Methods for Assets in Individual Accounts for Retirees: Life Income Annuities and Withdrawal Rules

As the baby boom generation begins to retire, more and more workers will have accumulated considerable assets in 401(k) plans and IRAs that have no particular method of payout. This paper examines the two basic, opposing methods that have been proposed as solutions to this problem. The first is the immediate life annuity, while the second is a fixed percentage of 4 percent of the initial account balance, increased each year after the first year of distribution by the rate of inflation. I calculate the lifetime income levels and risks these methods produce using a historical simulation of asset returns, interest rates, and inflation, as well as recent data on the pricing of immediate life annuities. I judge the life annuity an effective instrument to produce lifetime retirement income?generally somewhat better than the commonly used withdrawal rules. Because household needs and preferences are diverse, however, the government should not go beyond mild encouragement and education to promote the life annuity.
Phylogenetic ANOVA: The Expression Variance and Evolution (EVE) model for quantitative trait evolution

A number of methods have been developed for modeling the evolution of a quantitative trait on a phylogeny. These methods have received renewed interest in the context of genome-wide studies of gene expression, in which the expression levels of many genes can be modeled as quantitative traits. We here develop a new method for joint analyses of quantitative traits within and between-species, the Expression Variance and Evolution (EVE) model. The model parameterizes the ratio of population to evolutionary expression variance, facilitating a wide variety of analyses, including a test for lineage-specific shifts in expression level, and a phylogenetic ANOVA that can detect genes with increased or decreased ratios of expression divergence to diversity, analogous to the famous HKA test used to detect selection at the DNA level. We use simulations to explore the properties of these tests under a variety of circumstances and show that the phylogenetic ANOVA is more accurate than the standard ANOVA (no accounting for phylogeny) sometimes used in transcriptomics. We then apply the EVE model to a mammalian phylogeny of 15 species typed for expression levels in liver tissue. We identify genes with high expression divergence between-species as candidates for expression level adaptation, and genes with high expression diversity within-species as candidates for expression level conservation and/or plasticity. Using the test for lineage-specific expression shifts, we identify several candidate genes for expression level adaptation on the catarrhine and human lineages, including genes putatively related to dietary changes in humans. We compare these results to those reported previously using a model which ignores expression variance within-species, uncovering important differences in performance. We demonstrate the necessity for a phylogenetic model in comparative expression studies and show the utility of the EVE model to detect expression divergence, diversity, and branch-specific shifts.
Strategy, competition and investment: explaining the global divide in e-government implementation with policy variables

The rapid development of Information and Communication Technologies (ICTs) has created an environment for citizens to have greater access to their government and to make citizen-to-government contact more inclusive. Previous research does not examine the impact of national public policy initiatives that expand and improve e-government services. This study examines the global divide in e-government implementation by analysing the impact of national policies on the United Nations' Web Measure Index in 174 countries. A multiple regression analysis shows that e-governance is more extensive in countries that have a regulatory authority for telecommunications, encourage competition in their telecommunication industries and invest more financially in the development of ICTs.
Activation of G protein-coupled estradiol receptor 1 in the dorsolateral striatum enhances motivation for cocaine and drug-induced reinstatement in female but not male rats.

Background Estradiol potentiates drug-taking behaviors, including motivation to self-administer cocaine and reinstatement of drug-seeking after extinction in females, but not males. The dorsolateral stratum (DLS) is a region of the brain implicated in mediating drug-seeking behaviors and, more specifically, is a target brain area to study how estradiol regulates these behaviors. The estradiol receptors α, β, and G protein-coupled estradiol receptor 1 (GPER1) are all present in the DLS. In this study, the effects of activating GPER1 in the DLS on drug-seeking are investigated. Methods Gonad-intact male and female rats were trained to self-administer cocaine (0.4 mg/kg/inf) on a fixed-ratio 1 schedule of reinforcement. For 4 weeks, animals underwent testing on a progressive ratio schedule of reinforcement to determine their motivation to attain cocaine. Halfway through progressive ratio testing, a selective agonist targeting GPER1 (G1) was administered intra-DLS to determine the contribution of GPER1 activation on motivation for cocaine. The effects of intra-DLS GPER1 activation on drug-induced reinstatement after extinction were subsequently determined. Results Activation of GPER1, via intra-DLS G1 administration, potentiated females' motivation to self-administer cocaine. There was no effect of prior G1 treatment on extinction of cocaine-taking in females; however, G1 treatment resulted in greater drug-induced reinstatement (10 mg/kg cocaine, i.p.). There were no effects of intra-DLS GPER1 activation observed on motivation for cocaine or cocaine-induced reinstatement of responding in males. Conclusions These results support the conclusion that activation of GPER1 in the DLS enhances cocaine-seeking behaviors for female, but not male rats.
Multiobjective Multistate System Preventive Maintenance Model with Human Reliability

Modern equipment is designed to operate under deteriorating performance conditions resulting from internal ageing and/or external environmental impacts influencing downstream maintenance. This study focuses on the development of a multistate system (MSS) that considers a human reliability factor associated with maintenance personnel—a condition-based multiobjective MSS preventive maintenance model (MSSPMM). The study assumes that no more than one maintenance activity is performed to achieve the most appropriate preventive maintenance (PM) strategy and easy implementation and to reduce maintenance error due to human reliability. The MSS performance based on mean system unavailability and total maintenance cost is evaluated using a stochastic model approach, and then, the MSSPMM is used for optimisation. A customised version of the nondominated sorting genetic algorithm III is employed to ensure efficient solution of the PM model with human reliability—which is considered a constrained multiobjective combinatorial optimisation problem. The optimised solutions are determined from the nondominated Pareto frontier comprising the diversified PM alternatives. A helicopter power transmission system is used as an example to illustrate the efficacy and applicability of the proposed approach through sensitivity analyses with relevant parameters.
Transnational health protection strategies and other health-seeking behavior among undocumented and indigenous dairy workers in a rural new immigrant destination.

Abstract Latin American immigrants in new immigrant destinations (NIDs) experience numerous barriers that negatively impact their access to healthcare. Yet the wide range of health-seeking behaviors deployed in response to these barriers–particularly among those who are undocumented and indigenous–are not well understood. Further, studies of immigrant health in NIDs tend to take place in those locations, rather than using a multi-sited design. Building on NID scholarship, the transnational social protection literature, and work on structural vulnerability, this study uses a multi-sited research design to examine the health-seeking behaviors that undocumented and indigenous immigrant workers exhibit in a rural NID. Data consist of interviews conducted intermittently from 2010 to 2017 in Mexico and the U.S. with 56 individuals from indigenous villages in Veracruz who worked on dairy farms in Wisconsin and Minnesota, as well as expert interviews. We found numerous barriers to healthcare that together constituted a limited resource environment for undocumented dairy workers. This accentuated their structural vulnerability and influenced responses to health problems. Strategies among undocumented and indigenous immigrant dairy workers in a rural NID included: self-care, delaying care, relying on local ties, cross-border health consultation, cross-border health packages, and returning home for health. Furthermore, we found that women in the family or community often facilitated cross-border health activity, and that traditional folk medicine was common. We argue that these workers' health protection strategies not only serve to secure their individual status as productive workers, but on a larger scale, they play an important part in preserving the migrant labor regime in this rural NID. Further, we argue that the indigenous knowledge that is transmitted largely by women via immigrants’ informal social networks is an important yet often invisible part of the carework that maintains this relatively new labor force.
Minority Entrepreneurship and Access to Finance

We explore whether financial access explains persistent gender and racial imbalance in entrepreneurship. The 1979 NLSY overlaps with bank deregulation events between 1971 and 2001, permitting a difference in differences analysis of the propensity for young people to attempt entrepreneurship. We find that the movement away from local finance supported new entry by African American men into entrepreneurship, but not by women of any race. We show that financial access is an important determinant of the propensity of young adults to become entrepreneurs and provide new evidence about a mechanism through which the demographic gap in entrepreneurship might be closed.
How “special needs” vouchers deceive the public and silence the right to inclusive education

The rapid growth of special needs vouchers has been accompanied by the loss of historic civil rights and protections under the Individuals with Disabilities in Education Act (IDEA) and the American...
Five-year changes in objectively measured cardiorespiratory fitness, physical activity, and sedentary time in mid-to-late adulthood.

This study examined five-year changes in cardiorespiratory fitness, physical activity, and sedentary time in mid-to-late aged adults. Fifty-seven participants completed baseline and follow-up treadmill exercise tests and physical activity monitoring. We observed a 14% decline in fitness (p<.001), 12% decrease in physical activity (p= 0.010), and non-significant increase in sedentary time (p=.196). Age was negatively associated with five-year change in physical activity (r=-.31; p=.02) and this decline was strongest among APOE e4 carriers (g=-0.75). Novelty: • Cardiorespiratory fitness and physical activity significantly declined from mid-to-late adulthood, these findings were most pronounced among older adults and those with genetic risk for Alzheimer's disease.
HIV/AIDS and Screening Efficacy of African American Students

This study examined African American students’ perceived fear of having a seropositive human immunodeficiency virus (HIV) status, their general self-efficacy, and screening efficacy. General self-efficacy is believed to be a factor in facilitating change in one’s behavior. The sample (N = 398) consisted of graduate and undergraduate African American students enrolled at one Historically Black College and University. About one-fifth of the sample reported they were afraid to be screened for HIV/AIDS (acquired immune deficiency syndrome). t-tests were conducted to determine if there were differences between students who feared being screened for HIV/AIDS and those who did not fear being screened. Differences were found between the two groups on their perceived fear of being HIV positive, their general self-efficacy, and their screening efficacy. Implications for Family and Consumer Sciences professionals and others include placing more emphasis on reducing fears and increasing efficacy as a means to facilitate a change in health behavior.
A plasma betatron without gas breakdown

Following Budker's proposal [1] , experiments on plasma betatrons were carried out in several laboratories. Large conduction currents were observed as a result of gas breakdown, but the current of energetic electrons did not exceed 10 A. We adopted plasma injection to start a beam in good vacuum. The chamber consisted of outer and inner glass pipes lined with stainless steel mesh at radii of 5 cm and 2 cm, respectively. A toroidal field of 2 - 3 kG was applied along with a vertical field of up to 1.4 kG. Plasma was injected by coaxial guns, 1/4 inch in outer diameter, without increasing the neutral pressure significantly. A 20 A beam was accelerated to a peak energy of 1 MeV with little loss and then dumped to the chamber wall by a spiller field. The current was enhanced to more than 100 A by the addition of electron injection using a field emission cathode.
Race as Praxis in the Philippines at the Turn of the Twentieth Century

This article takes as its point of departure the disparity between the empirical poverty of race and its survival, even growth, as a way of understanding history and politics or more specifically, history as politics and politics as history in the Philippines during the nineteenth century. What interested me primarily was how race as a form of praxis is too often and easily ascribed to a discredited science that came into vogue during the nineteenth century. While race rhetoric certainly drew its authority from scientific positivism, its spokespeople also invoked the fields of law, philosophy, and religion. Yet for most people, race was not a question to be resolved by scientific investigation, but a weapon in a war or conflict between unequal opponents. Not surprisingly, questions around the existence or impossibility of a Filipino race were most fully debated and developed in a time of war the 1896 Philippine Revolution, and the 1899 Philippine-American War, which began just after the outbreak of war between the U. S. and Spain in 1898. My article charts the genealogy of these debates, and the relationship of race to the narration of anti-imperial movements and alternative cosmopolitanism.
Multiple myeloma cell killing by 8-chloro-adenosine overcomes the survival mechanisms generated by the receptor tyrosine kinase, MET

5878 Multiple myeloma (MM) is an invariably fatal plasma cell malignancy, primarily due to therapeutic resistance that ultimately arises. Much of the resistance is due to the expression of survival factors such as MET, BCL-X L , and IL-6. Despite this, we have established that the ribonucleoside analog, 8-chloro-adenosine (8-Cl-Ado), is cytotoxic to a number of MM cell lines that are resistant to traditional chemotherapeutic agents. Previously we demonstrated that 8-Cl-Ado treatment of a MM cell line, MM.1S, results in a dose-dependent accumulation of its triphosphate with a progressive decrease of the endogenous ATP pool [Cancer Res. 61: 5474, 2001]. In addition, we have shown that the analog is incorporated into RNA and prematurely terminates transcription. These events lead to an inhibition of RNA synthesis with a maximum effect on mRNA synthesis [Cancer Res. 63: 7968, 2003]. Because 8-Cl-Ado is able to overcome strong survival signals present in MM cells and inhibits mRNA synthesis it is likely that the drug induces cytotoxicity by diminishing the expression of critical MM survival genes. MET, a receptor tyrosine kinase, promotes survival signaling in numerous cell types and is an autocrine-loop with its ligand, hepatocyte growth factor (HGF), in both primary MM cells and cell lines. Furthermore, MM patients with high serum HGF levels have been associated with a poorer prognosis. We found that 8-Cl-Ado treatment reduces the expression level of MET mRNA by >60%. This was accompanied with a reduction in MET protein levels and induction of cell death. To establish the role of MET on survival of MM cells, we have generated MM.1S clones stably expressing the pU1-MET 560 hammerhead ribozyme. Of the clones isolated, 18 out of 24 had reduced level levels of MET. No clones with MET mRNA were found to endure the selection process, suggesting MET may be necessary for MM cell survival under normal conditions. We hypothesized that clones with lower levels of MET mRNA would be more sensitive to 8-Cl-Ado-induced toxicity. To test this, clones with 30-50% of the basal MET mRNA levels were assessed for 8-Cl-Ado mediated effects. Preliminary data using real-time RT-PCR assays indicate that treatment with 8-Cl-Ado further reduced MET transcript levels in these clones. Kinetic analysis of 8-Cl-Ado-induced caspase 3 activity showed a >2 fold caspase 3 induction in the MET ribozyme clones 6-12 hours earlier than the parental line. Likewise, PARP immunoblot analysis also showed an induction of PARP cleavage in MET expression levels; thus, 8-Cl-Ado-induced cytotoxicity is enhanced in cells with lower basal levels of MET .
Characterization of a Titanate Based Ceramic for High Level Nuclear Waste Solidification

Detailed characterization of nuclear waste forms is necessary if subsequent behavior in thermal, aqueous and radiation fields is to be understood. In this paper, we describe the results of detailed studies of the physical properties of a complex polycrystalline titanium-based ceramic developed as an alternative to borosilicate glass for solidification of high level liquid nuclear wastes. Microstructure, phase relations, and thermal stability are described.
Stress, Behavior Patterns, and Coronary Disease!

Coronary heart disease is a clinical disorder that results from damage to the coronary arteries, the latter being called coronary artery disease or atherosclerosis (Friedberg, 1966); a nontechnical term for it is hardening of the arteries. Myocardial infarction is one of the most common forms of clinical coronary disease.
Informed consent, the parturient, and obstetric anesthesia.

Awareness of the ethical dimensions in medical practice is a cornerstone to the art of medicine. In contemporary medicine, informed consent has become a routine component of ethical practice. The current trend toward a consumeroriented approach in medicine may sometimes relegate the role of informed consent to legal standard of care rather than an enhancement of the patientphysician relationship. However, in reality, medical, legal, ethical, and philosophical issues are all intertwined in the informed consent process, further complicating this complex issue. There is no universal standard of care with respect to informed consent. Several rules have been proposed; first, the “one percent” rule; second, the “death” rule; third, the “reasonable” rule; fourth, the “all-risk” rule; fifth, the “all-risk rule minus negligible severity of incidence”, and finally, the “good judgment” rule.* The “one percent” rule indicates that anesthesiologists are supposed to inform patients of complications that have an incidence of greater than one percent. In the “death” rule, if the anesthesiologist says that the patient could die as a result of his/her administration of anesthesia, then this complication it would cover all other complications because nothing is as bad as dying. The “reasonable” rule says that the anesthesiologist should inform a patient of all risks that a reasonable patient would want to know. The “all-risk” rule indicates that an anesthesiologist needs to inform all patients of all risks regardless of incidence or reasonableness. And, finally, the “good judgment” rule indicates that an anesthesiologist needs to balance frightening the patient with informing the patient.* In the past, informed consent to anesthesia was usually included within the consent for surgery. Today, separate specific consent for anesthesia is required in most states. The subspecialty of obstetric anesthesia presents a unique spectrum of challenges to the process of informed consent. Although many parturients present with a significant amount of prior knowledge regarding labor analgesia, others may have little or no understanding of labor and delivery and pain relief options. Furthermore, many physicians are concerned that the pain of labor may invalidate the process of informed consent. Nevertheless, it has been well
Urban Middle-Grade Student Mathematics Achievement Growth under Comprehensive School Reform.

Recognizing the need to implement standards-based instructional materials with school-wide coherence led some Philadelphia schools to adopt whole-school reform (WSR) models during the late 1990s. The authors report on the relation between mathematics achievement growth for middle-grade students on the Pennsylvania System of School Assessments and the number of years schools implemented either a WSR model with National Science Foundation-supported mathematics curriculum or a WSR model without a mathematics curriculum component, from 1997 to 2000. As the authors hypothesized, mathematics achievement gains (Grades 5-8) were positively related to the number of years those schools were implementing a specific mathematics curricular reform. Additional analyses indicated that the relation held for both computation skills and ability to apply mathematics concepts.
Controllability Transition and Nonlocality in Network Control

A common goal in the control of a large network is to minimize the number of driver nodes or control inputs. Yet, the physical determination of control signals and the properties of the resulting control trajectories remain widely underexplored. Here we show that (i) numerical control fails in practice even for linear systems if the controllability Gramian is ill conditioned, which occurs frequently even when existing controllability criteria are satisfied unambiguously, (ii) the control trajectories are generally nonlocal in the phase space, and their lengths are strongly anti-correlated with the numerical success rate and number of control inputs, and (iii) numerical success rate increases abruptly from zero to nearly one as the number of control inputs is increased, a transformation we term numerical controllability transition. This reveals a trade-off between nonlocality of the control trajectory in the phase space and nonlocality of the control inputs in the network itself. The failure of numerical control cannot be overcome in general by merely increasing numerical precision--successful control requires instead increasing the number of control inputs beyond the numerical controllability transition.
Shrub Seedling Establishment is Limited by Dispersal, Slow Growth, and Fire in Two Wet Pine Savannahs in Mississippi

Abstract Identifying the mechanisms that drive invasions of open habitats by woody species is critical for preserving diverse savannas. Trees can promote the establishment of bird-dispersed woody plant species in savannas by reducing dispersal limitation. Previous work in wet pine savannas has shown that densities of bird-dispersed shrubs are higher and species richness of herbaceous species, most of which are not bird-dispersed, is lower in areas near trees. To test the hypothesis that shrub seedling density in wet pine savannas was limited by dispersal and thus the availability of perches for seed-dispersing birds, seed traps and artificial perches were placed near and away from pines. To measure fire-induced mortality of trees and shrubs, Pinus elliottii juveniles and shrub seedlings that had emerged during a fire-free interval were quantified before and after fires. Trees provided perches for birds that dispersed shrubs, thereby reducing dispersal limitation of shrubs. Significantly more seeds of the ...
Simple criteria for finding (nearly) optimal vaccination strategies

Strategies for best controlling the spread of the diseases with limited vaccine available are explored. I use influenza as a representative disease in point. The model describes the dynamics of influenza spread among multiple groups that have different risks and activity levels. I define a core group consisting of individuals with occupations that brings them in contact with many other people in a day. These occupations may include service industries, teachers, health care, and government workers, to name a few. High-risk individuals are those as typically designated for: children under 5 and adults over 50, people with weakened immune systems as well as emergency and health care personnel. Under certain conditions, shifting vaccination resources away from the high-risk group to the high-activity group will result in improved herd immunity in both the high-risk group and the population as whole. This results in more high-risk people protected even though less of them are being vaccinated, with the obvious implications that current vaccination policies may be far less then optimal. I show that the criteria for the optimal strategy can be derived from simple expressions gleaned from the expression for the basic reproductive number.
Lifetime measurement in the α system (C3Δ3-X3Δ3) of TiO

Abstract The radiative lifetimes of two rotational levels of the v′ = 2 level of the C3Δ3 state of TiO have been measured using laser-induced fluorescence and delayed coincidence counting. Individual rotational levels are excited and observed. The measured lifetimes are τJ = 17 = 28.21 + 0.15 nsec and τJ = 87 = 29.74 ± 0.86 nsec. Argon-TiO collision cross sections have been determined for the two rotational levels and are found to differ by 30%.
Steric interactions in 2‐substituted imidazoles. The molecular structure of 1‐methyl‐2‐phenylimidazole and 1‐methyl‐4‐phenylimidazole

The crystal and molecular structures are reported for two isomeric imi- dazoles: 1-methyl-2-phenylimidazole (1) and 1-methyl-4-phenylimidazole (2). In molecule (2) the phenyl ring is rotated by 7.3 o from the hete- rocyclic plane due to steric interactions. The steric congestion is much more severe in (1), with the adjacent methyl and phenyl substituents mininizing nonbonded interactions via a 32.3 o rotation of the phenyl ring and a 0.159 A displacement of the methyl carbon from the hetero- cyclic plane
Human reserve pluripotent mesenchymal stem cells are present in the connective tissues of skeletal muscle and dermis derived from fetal, adult, and geriatric donors.

This study details the profile of 13 cell surface cluster differentiation markers on human reserve stem cells derived from connective tissues. Stem cells were isolated from the connective tissues of dermis and skeletal muscle derived from fetal, mature, and geriatric humans. An insulin/dexamethasone phenotypic bioassay was used to determine the identity of the stem cells from each population. All populations contained lineage-committed myogenic, adipogenic, chondrogenic, and osteogenic progenitor stem cells as well as lineage-uncommitted pluripotent stem cells capable of forming muscle, adipocytes, cartilage, bone, fibroblasts, and endothelial cells. Flow cytometric analysis of adult stem cell populations revealed positive staining for CD34 and CD90 and negative staining for CD3, CD4, CD8, CD11c, CD33, CD36, CD38, CD45, CD117, Glycophorin-A, and HLA DR-II. Anat Rec 264:51–62, 2001. © 2001 Wiley-Liss, Inc.
The effect of removing hapten from the surface of hapten-bearing cells in tolerance induced by DNP-isologous IgG.

Abstract When tolerance is induced by DNP mouse gammaglobulin (DNP-MGG) lymphocytes with the hapten DNP persisting on their surface can be found in the spleens of the tolerant mice. These hapten-bearing cells (HBC) have been found to correlate with the presence of tolerance and to disappear when tolerance is either reversed or wanes naturally. Because of this it has been postulated that HBC may represent a receptor blockade. To test this hypothesis tolerance was induced in mice by injection of various doses of DNP-MGG and the tolerant spleen cells were treated with Pronase to remove hapten from the lymphocyte surface. After Pronase treatment the cells were cultured with either the T-dependent antigen TNP sheep red blood cells or the T-independent antigen DNP-Ficoll and their immune response was assayed. The experiments showed that removal of hapten from the surface of lymphocytes from tolerant animals did not reverse tolerance. In addition, removal of HBC from tolerant spleen cells by panning on DNP-gelatin-coated plates prior to culture did not reverse tolerance. Thus, the HBC does not represent a receptor blockade of DNP-specific lymphocytes. In addition, presence of HBC does not appear to be necessary to maintain tolerance in other B cells. The significance of the hapten-bearing cell in this model of tolerance is discussed.
Conversion of progesterone to androsterone by testicular tissue at different stages of maturation

Abstract Information in the literature suggests that testes at different stages of development show marked variation in their capacity to synthesize androgens. In view of this information, we felt it would be of interest to investigate systematically the capacity of developing testes to convert progesterone to testosterone. For this purpose, testicular tissue from newborn, 13, 17, 20, 40 and 90-day-old rats was incubated with radiolabelled progesterone, and the formed radioactive testosterone determined. This study has shown that testicular tissue from newborn rats is capable of converting up to 59.0% of progesterone to testosterone. As testes develop, the capacity for testosterone biosynthesis declines. Testes from 20-day-old rats fail, almost completely, to convert progesterone to testosterone. As the testes continue to mature, testosterone synthesizing capacity returns gradually. The testicular tissue from 20-day-old rats, while not capable of converting progesterone to testosterone, metabolizes progesterone actively, but the major product is neither testosterone nor androstenedione, but a different substance; its identity is presently under investigation.
Mechanism of infection by Epstein-Barr virus II. Comparison of viral DNA from HR-1 and superinfected raji cells by restriction enzymes

Abstract Virus DNA (RS virus DNA) was directly isolated from Raji cells superinfected with Epstein-Barr virus derived from P3HR-1 cells and compared with original superinfecting virus DNA from P3HR-1 cells (HR-1 virus DNA) in agarose-gel electrophoresis after digestion with various restriction enzymes. Eco R-1 digestion of RS virus DNA produced 15 fragments identical to those from HR-1 virus DNA. However, two fragments, Eco R1 No. 6 (10 × 10 6 daltons) and Eco R1 No. 11 (4.6 × 10 6 daltons), observed in HR-1 virus DNA were not detected in RS virus DNA from superinfected Raji cells. In addition, the Eco R1 No. 4 (13.5 × 10 6 daltons) fragment of RS virus DNA showed a molar ratio of 2 whereas HR-1 virus DNA produced the same fragment with a molar ratio of 1. Electrophoresis patterns of virus DNA digested with Hin d III, Bam H-I, Hpa I, and Sal I were also examined. In general, both types of virus DNA produced similar patterns after gel electrophoresis, with minor differences in molar ratios after being treated with the restriction enzymes suggesting that RS virus DNA obtained by superinfection of Raji cells is basically identical to HR-1 virus DNA but may contain a population of DNA a little more heterogenous than HR-1 virus DNA.
INTERACTION BETWEEN BENDING VIBRATIONS AND MOLECULAR ROTATION: A MODEL STUDY

The classical mechanics of the interaction between bending vibration and molecular rotation is studied for a simple rigid bender model. A one-dimensional representation of rotational motion enables surfaces of section to be constructed. Quasiperiodic, resonant and chaotic motions are identified, and related to characteristic patterns of vibration-rotation energy flow.
Text categorization for multiple users based on semantic features from a machine-readable dictionary

The text categorization module described here provides a front-end filtering function for the larger DR-LINK text retrieval system [Liddy and Myaeing 1993]. The model evaluates a large incoming stream of documents to determine which documents are sufficiently similar to a profile at the broad subject level to warrant more refined representation and matching. To accomplish this task, each substantive word in a text is first categorized using a feature set based on the semantic Subject Field Codes (SFCs) assigned to individual word senses in a machine-readable dictionary. When tested on 50 user profiles and 550 megabytes of documents, results indicate that the feature set that is the basis of the text categorization module and the algorithm that establishes the boundary of categories of potentially relevant documents accomplish their tasks with a high level of performance.This means that the category of potentially relevant documents for most profiles would contain at least 80% of all documents later determined to be relevant to the profile. The number of documents in this set would be uniquely determined by the system's category-boundary predictor, and this set is likely to contain less than 5% of the incoming stream of documents.
Regulation of Drosophila α- and β-tubulin genes during development☆

Abstract Both the α and the β subunit of tubulin in Drosophila melanogaster are encoded by small multigene families. Using heterologous hybridization probes representing chicken α- and β-tubulin genes, four complementary α- and four β-tubulin gene sequences from Drosophila have been isolated. Each gene has been individually mapped cytogenically by in situ hybridization of nucleic acid probes to polytene chromosomes. It is clear that the genes in each family are dispersed rather than arranged in tandem arrays or clusters. Furthermore, α- and β-tubulin genes are not physically linked as α-β pairs. Transcripts from individual genes are differentially accumulated at particular stages of Drosophila development. This differential gene activity may provide expression of functionally specialized tubulin subunits. Alternatively, differences in expression may reflect tissue specific patterns of gene utilization.
Rhenium-188 therapy of experimental hydrocephalus

Chronic hydrocephalus was produced in adult mongrel cats by the intracisternal injection of kaolin. After 10 days, Rhenium-188 in doses of 0.75 to 1.80 mCi was given by lateral ventricle to lateral ventricle perfusion to one group of hydrocephalic cats. Another group received doses of 4.6 to 5.1 mCi Rhenium-188 by a single intraventricular injection. Neither group showed diminution in the rates of formation or absorption of CSF or in the ventricular volume, nor was there evidence of alteration in thickness of the cortical mantle as shown by air ventriculograms. T/M ratios with Na125 I were performed using choroid plexuses of normal, hydrocephalic, and Rhenium-188 treated hydrocephalic groups. The tissue-to-medium ratios were identical in both the normal and the hydrocephalic groups but were significantly lower in the Rhenium-188 treated cats.
Assessing implementation of evidence-based childhood obesity prevention strategies in schools

Objective Research suggests that schools can play a key role in obesity prevention by implementing evidence-based strategies promoting student health. This study explores school climate factors underlying implementation of evidence-based health and wellness policies and practices in Kindergarten–8th grade programs in the Southwestern United States.
Measuring the Pharmacodynamic Effects of a Novel Hsp90 Inhibitor on HER2/neu Expression in Mice Using 89Zr-DFO-Trastuzumab

Background The positron-emitting radionuclide 89Zr (t1/2 = 3.17 days) was used to prepare 89Zr-radiolabeled trastuzumab for use as a radiotracer for characterizing HER2/neu-positive breast tumors. In addition, pharmacodynamic studies on HER2/neu expression levels in response to therapeutic doses of PU-H71 (a specific inhibitor of heat-shock protein 90 [Hsp90]) were conducted.
Elastic beam problem with higher order derivatives

Abstract We apply a fixed point theorem to obtain sufficient conditions for existence of triple positive solutions of the symmetric nonlinear fourth-order boundary value problem u ( 4 ) ( t ) = a ( t ) f ( t , u ( t ) , | u ′ ( t ) | , u ″ ( t ) , | u ‴ ( t ) | ) , t ∈ ( - 1 , 1 ) , u ( - 1 ) = u ′ ( - 1 ) = 0 , u ( - t ) = u ( t ) , t ∈ [ - 1 , 1 ] , where f satisfies certain growth conditions. In the process, we obtain nontrivial a priori bounds on the derivatives of the solution.
Synthesis and characterization of a series of novel nickel(II)/nickel(I) complexes. Crystal structures of [NiCl2(dcpm)], [Ni(dcpm)2](NO3)2·2EtOH, [Ni2Cl2(μ-dcpm)2(μ-H)] and [Ni2(μ-PCy2)2(PCy2Me)2]; dcpm=bis(dicyclohexylphosphino)methane

Abstract The complexes [(dcpm)NiCl2] (1), [Ni2Cl2(μ-dcpm)2(μ-H)] (3), [Ni2(μ-PCy2)2(PCy2Me)2] (4) and [Ni(dcpm)2](NO3)2·2EtOH (2), dcpm=bis(dicyclohexylphosphino)methane, have been prepared and characterized by 31P, 1H NMR (or EPR) as well as X-ray crystallography. The salt NiCl2·6H2O was found to react with dcpm to form the monomeric, four-coordinate, diamagnetic complex [(dcpm)NiCl2] (1). Compound 1 was then reduced with nBu3SnH (or LiH with heating) in toluene at room temperature to form the air sensitive ‘A-frame’ complex [Ni2Cl2(μ-dcpm)2(μ-H)] (3). The NiNi bond distance for 3 was found to be 2.904(3) A showing a lack of any NiNi metal bonding. [Ni2(μ-PCy2)2(PCy2Me)2] (4) was then formed by the reaction of 1 and excess LiH, heating to 90°C in an oil bath. [Ni2Cl2(μ-dcpm)2(μ-H)] (3) was shown to be an intermediate in the synthesis of the bridging phosphido nickel complex. The NiNi bond distance in 4 is 2.3910(8) A corresponding to a single NiNi metal bond. The reaction of Ni(NO3)2·6H2O with dcpm in ethanol yields the square planar complex [Ni(dcpm)2](NO3)2·2EtOH (2).
Priorities in Educational Research.

This article emphasizes the need for a coordinative agency to survey, project, and direct funding for educational research. Studies are recommended on characteristics of children in the learning encounter; educational readiness for the very young child from various social settings; and the exploration of programs to meet children's needs across the total school range. The teacher, his personal qualities and behavior in the teaching act, will be a primary focus in research. Adequate means of evaluating school programs, particularly innovative programs must be devised. Researchers must reveal means whereby the teacher can become more effective on an individual basis with both child and parent.
Immunology: Surprising side effects.

A drug that normally suppresses an immune response by trapping lymphocytes in lymphoid organs results in the elimination of a chronic viral infection when applied at low doses. Why should this be?
Conversation analytic claims

L'auteur apporte des arguments pour defendre la validite et la possibilite de generalisation des methodes d'analyse conversationnelle, et precise quelles sont les revendications des analystes de conversations
Cheating in School: What We Know and What We Can Do

Davis, Stephen F., Patrick F. Drinan, and Tricia Bertram Gallant; Malden, MA: Wiley-Blackwell; Publication Date: 2009; Price: $23.95; ISBN-13: 978–1-4051–7804-4. OK, TCH readers, are you ready for ...
Management of persistent groin pain after transobturator slings

Prolonged groin pain after transobturator tape is uncommon. Three women reported groin pain that had not improved by 3 months postoperatively. Combined steroid and local anesthetic was effective for pain relief in all patients. The differential diagnosis of persistent groin pain after transobturator tape includes adductor muscle strain, osteitis pubis, obturator/groin abscess, structural adhesions, and inflammation, edema or nerve entrapment of the anterior branch of the obturator nerve. No side effects of treatment were noted. Patients that do not respond to local injection may require mesh dissection and excision.
Water budgets of martian recurring slope lineae

Abstract Flowing water, possibly brine, has been suggested to cause seasonally reappearing, incrementally growing, dark streaks on steep, warm slopes on Mars. We modeled these Recurring Slope Lineae (RSL) as isothermal water flows in thin surficial layers driven by gravity and capillary suction, with input from sources in the headwall and loss to evaporation. The principal observables are flow duration and length. At 40% porosity, we find that flow thicknesses reaching saturation can be just 50 mm or so and freshwater RSL seasonally require 2–10 m3 of H2O per m of source headwall. Modeled water budgets are larger for brines because they are active for a longer part of each day, but this could be partly offset by lower evaporation rates. Most of the discharged water is lost to evaporation even while RSL are actively lengthening. The derived water volumes, while small, exceed those that can be supplied by annual melting of near-surface ice (0.2–2 m3/m for a 200-mm melt depth over 1–10 m height). RSL either tap a liquid reservoir startlingly close to the surface, or the actual water budget is several times smaller. The latter is possible if water never fully saturates RSL along their length. Instead, they would advance like raindrops on a window, as intermittent slugs of water that overrun prior parts of the flow at residual saturation. Annual recharge by vapor cold trapping might then be supplied from the atmosphere or subsurface.
Developmental patterns as a function of ethnicity

Abstract The emergence of some developmental motor of speech and social patterns of ethnically-different children are analyzed and found to be different. The implications of these differences are discussed.