cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of loading history on stress corrosion cracking in high strength steel

Abstract The effect of preloading on crack nucleation time was examined with compact tension specimens having various notch radius in 0.1N-H 2 SO 4 aqueous solution for 200°C tempered AISI 4340 steel. Crack nucleation time t n increases by preloading for a given apparent stress intensity factor K p 2 . The curve K ϱ 2 vs. t n deviates upward from the curve for the non preloading case. A linear relationship between the crack nucleation time and parameter (2K ϱ 2 /(πϱ) 1 2 −(2K ϱ 2 /(πϱ) 1 2 ) th ) is seen in semi-log diagram, where (2K ϱ 2 /(πϱ) 1 2 ) th is taken as the value at t n = α due to preloading. The apparent threshold stress intensity factor increases with K ϱ 2 which is the apparent stress intensity factor of preloading. A detached crack is nucleated at some distance from the notch root and extends in a form of circle. This distance increases with increasing K ϱ 2 . The effect of load reduction during crack growth was examined. When the K -value was reduced from K 1 to K 2 , an incubation time was observed before the crack started growing under the K 2 -value. The incubation time t m tends to increase with increasing ΔK = K 1 - K 2 . The threshold stress intensity factor was also found to increase for high load reduction. In order to explain these experimental results, a new dislocation model is proposed on the basis of stress induced diffusion of hydrogen in high stress region ahead of the notch root or a crack. This model suggests that the change in the crack nucleation time and the increase of the incubation time due to preloading or load reduction are caused by reducing the hydrostatic pressure and by spreading the hydrogen saturated region which requires more time for the hydrogen accumulation due to preloading or load reduction. The theory predicts the experimentally observed relations between (2K ϱ 2 /(πϱ) 1 2 − (2K ϱ 2 /(πϱ) 1 2 ) th ) and t n and between log t in and ΔK.
The Neogene intra-Carpathian basins

The Carpathian intra-arc region is composed of two distinct types of sub-basins, the peripheral basins lying adjacent to the arc, and the central basins that lie in the central intra-arc region. Both sets of basins have approximately 2-6 km of Miocene and younger sediment, 20-25 km pre-Miocene crust, and elevated heat flow. Examination of their subsidence histories suggests that the basins are thermal in origin and formed by twofold stretching. In the central basins this twofold stretching must be combined with an additional mechanism for introducing heat into the lithosphere that does not significantly alter the structure or thickness of the stretched crust.
Utilization of maternal health care services in the department of Matagalpa, Nicaragua

OBJECTIVES: To better understand the individual and community factors and perceptions that influence women's health care-seeking behaviors during pregnancy in order to increase women's utilization of maternal health services. METHODS: This study investigates the logistical and sociocultural barriers influencing women's utilization of maternal health services through 37 semi-structured in-depth interviews with women from the department of Matagalpa, Nicaragua. RESULTS: Results reveal that delays in seeking health care during pregnancy are influenced not only by poor access to care and economic barriers but also by individual and community knowledge and acceptance of maternal health services. Partner support, previous maternal health care experiences, and the degree of communication with other women and health workers affect women's decisions to seek care. CONLUSIONS: Evidence suggests that in order to improve maternal health outcomes in this region, interventions must be targeted at a hierarchy of levels: individual, household, and community.
Wounding to heal: the role of the body in self-cutting

This paper offers an in-depth phenomenological exploration of the self-cutting experience and the meanings of the gesture, the wound, and the resulting scar. The phenomenon of self-cutting lends itself to qualitative questions. To address these questions, six female self-cutters were interviewed. Their audiotaped responses were analysed according to the phenomenological method of data analysis (Giorgi, 1975). The purpose of such research is to explicate the structure of a phenomenon from the descriptions of individuals who experience it. By including all that was common across participants' situated structures, the general structural description or essential meaning of the phenomenon was reached. Results revealed that ‘bodily mineness’, pain, despair, and competence all factor into the embodied nature of self-cutting. The act of self-cutting pulls the individual together while simultaneously tearing her apart with its self-destructive, shaming, and addictive consequences. Nevertheless, findings reveal how...
Transcranial magnetic stimulation during voluntary action: Directional facilitation of outputs and relationships to force generation

Single-pulse transcranial magnetic stimulation (TMS) of the human motor cortex evokes simple muscle jerks whose physiological significance is unclear. Indeed, in subjects performing a motor task, there is uncertainty as to whether TMS-evoked outputs reflect the ongoing behavior or, alternatively, a disrupted motor plan. Considering force direction and magnitude to reflect qualitative and quantitative features of the motor plan respectively, we studied the relationships between voluntary forces and those evoked by TMS. In five healthy adults, we recorded the isometric forces acting a hand joint and the electromyographic activity in the first dorsal interosseous (FDI) muscle. Responses obtained at rest were highly invariant. Evoked responses obtained while subjects generated static and dynamic contractions were highly codirectional with the voluntary forces. Such directional relationships were independent of stimulation intensity, stimulated cortical volume, or magnitude of voluntary force exerted. Dynamic force generation was associated with a marked increase in the magnitude of the evoked force that was linearly related to the rate of force generation. The timing of central conduction was different depending on functional role of the target muscle, as either agonist or joint fixator. These results indicate that the architecture of motor plans remain grossly undisrupted by cortical stimulation applied during voluntary motor behavior. The significant magnitude modulation of responses during dynamic force generation suggests an essential role of the corticospinal system in the specification of force changes. Finally, the corticospinal activation depends on the functional role assumed by the target muscle, either postural or agonist.
A capillary liquid chromatographic/tandem mass spectrometric method for the quantification of γ-aminobutyric acid in human plasma and cerebrospinal fluid

A sensitive and reliable method for the determination of gamma-aminobutyric acid (GABA), a major inhibitory neurotransmitter, in human plasma and cerebrospinal fluid (CSF) has been developed. The method is based on capillary liquid chromatography (LC)/tandem mass spectrometry (MS/MS) using deuterium-labeled GABA (gamma-aminobutyric acid-2,2-D(2), GABA-d(2)) as internal standard. Pre-column derivatization with 7-fluoro-4-nitrobenzoxadiazole (NBD-F) was deployed, allowing both effective in-line pre-concentration and sensitive tandem MS detection of the analyte. An extraction column (10 mm x 0.25 mm, 7 microm, C(18)) was used for preconcentrating and stacking the sample. Separation was carried out on an analytical column (50 mm x 0.25 mm, 5 microm, C(18)). Characteristic precursor-to-product ion transitions, m/z 267--> 249 (for NBD-GABA) and m/z 269--> 251 (for NBD-GABA-d(2)) were monitored for the quantification. A linear calibration curve from 10 to 250 ng/mL GABA with an r(2) value of 0.9994 was obtained. Detection limit was estimated to be 5.00 ng/mL GABA (S/N = 3). Human plasma and CSF samples were analyzed. The concentrations of GABA were found to be 98.6 +/- 33.9 ng/mL (mean +/- S.D., n = 12), and 44.3 +/- 10.0 ng/mL (n = 6) in plasma and CSF, respectively.
Physical studies on the effect of chromosomal RNA on reconstituted nucleohistones.

Rabbit liver DNA was reconstituted with histones, nonhistone proteins, and chromosomal RNA-protein complex from 2 m NaCl-5 m urea-0.01 m Tris-0.001 m mercaptoethanol (pH 8.0). Through studies on the melting profiles of such reconstituted nucleohistones it was found that chromosomal RNA-protein may constitute a structural component to chromatin. In addition, it was also found that the binding of exogenous lysine-rich histone I to native chromatin did not cause further repression of that chromatin when native chromatin was allowed to interact with exogenous histone I in 0.01 m Tris, pH 8.0.
Anti-Inflammatory Effects of Specific Cyclooxygenase 2,5-Lipoxygenase, and Inducible Nitric Oxide Synthase Inhibitors on Experimental Autoimmune Anterior Uveitis (EAAU)

Purpose: Inflammation, in general, causes the release of a variety of inflammatory mediators that in turn induce cyclooxygenase (COX) 2, nitric oxide synthase (iNOS) and 5-lipoxygense (LP) synthesis, producing large amounts of inflammatory prostaglandins (PG), nitric oxide (NO), and leukotriene (LT) B4. Therefore, inhibition of these enzymes may abrogate intraocular inflammation in experimental autoimmune anterior uveitis (EAAU). Methods: Lewis rats were immunized with melanin-associated antigen (MAA) isolated from bovine iris and ciliary body. These animals were divided into three groups. The first group of rats received subcutaneous injection of COX 2 inhibitor CS 236 at different time points. The second and third groups of animals received subcutaneous aminoguanidine (AG), an iNOS inhibitor, and nordihydroguaiaretic acid (NDGA), a 5-LP inhibitor, respectively. Control animals received vehicle. Rat eyes were examined daily by slit-lamp biomicroscopy from Day 7 to 30 post injection for uveitis. Animals w...
Follow-up evaluation of a high school eating disorders screening program: knowledge, awareness and self-referral

Abstract Purpose To conduct a regional, follow-up evaluation to assess the implementation and effectiveness of the National Eating Disorders Screening Program (NEDSP), conducted in high schools nationwide in the spring of 2000. Methods Four New England high schools participated in a postscreen evaluation 1 to 2 months after implementation of NEDSP. A 35-item, self-report postscreen survey was administered to students in classrooms with assistance from school health staff and teachers. School staff involved in the screening were also interviewed. Logistic regression was used to estimate the odds that students talked to an adult or peers about their screening score. Results Data from 592 girls and 435 boys were included in the analysis in the four high schools participating in the program evaluation. NEDSP helped to identify students at risk and encouraged students to speak to others about their screening score and eating disorder symptoms. One-quarter of girls and one-fifth of boys reported talking with at least one adult about their EAT-26 screening score. Girls felt more strongly than boys that the program helped them learn about eating disorders, change their thinking related to eating disorders and body image, and talk to friends about eating disorders. Overall, the students felt that the program was helpful and would recommend it to their friends. Conclusions Early detection of eating disorders in adolescents may shorten the interval between onset of symptoms and treatment, which has the potential to reduce the length of illness and morbidity associated with untreated eating disorders. Our findings suggest that high-school-based screening may be an effective way to facilitate early detection of eating disorder symptoms in adolescents.
The Undergraduate Marketing Curriculum: A Descriptive Overvriew

This study describes the current state of the undergraduate marketing curriculum. A questionnaire was developed and sent to the chairperson of the Marketing Department at each of the 230 AACSB-accredited schools, requesting information on course offerings, course requirements, and student prerequisites in several areas; information on the type and extent of computer usage, the extent of use of computer simulations, and the amount of exposure to spreadsheets and statistical software packages was also requested. Study results may provide a yardstick for the assessment of marketing programs and may aid in planning the future development of such programs.
Crystal faces and cleavage planes in quartz as templates in biological processes.

Some species of minerals, when comminuted and aerosolized in the form of respirable-size particulate dusts, are recognized as capable of producing disease in man after their inhalation. Comprehensive listings of such agents are in the current literature (e.g. in Aponte, 1970; Langer & Mackler, 1972; Ehrenreich et al. 1973a, b) and many of these and their effects are well known and receive much attention. Asbestos fibres of all varieties, ampbibole and quartz contaminated talcum powders (see Rohl et al. 1976), fibrous amphiboles and their cleavage fragments which contaminate the ambient environment (e.g., the contamination of Lake Superior with cummingtonite-grunerite, as discussed in Bowes, Langer & Rohl, 1977), have been the subject of recent intensive investigations mostly due to their protential impact to large segments of the general population.
Ignoble savages and other European visions: The La Pérouse affair in Samoan history ∗

(1991). Ignoble savages and other European visions: The La Perouse affair in Samoan history. The Journal of Pacific History: Vol. 26, No. 1, pp. 3-26.
What controls the uptake of transient tracers in the Southern Ocean

CFC-11, bomb-D 14 C, and anthropogenic CO2. The model reproduces the observed relationship between CFC-11 and bomb-D 14 C and suggests that the upper branch of the residual overturning flow in the Southern Ocean is about 14 Sv, supporting previous inferences based on the observed buoyancy distribution and air-sea buoyancy fluxes. Scale analysis suggests that the limit of fast air-sea gas exchange is applicable to CFC-11, for which the surface concentration is close to equilibrium and cumulative ocean uptake is largely determined by physical transport processes. In the slow gas exchange limit, applicable to bomb-D 14 C, the surface concentration is far from equilibrium and the cumulative uptake is most sensitive to the parameterization of the gas transfer coefficient. Anthropogenic CO2 falls between those two limit cases and is sensitive to both transport processes and the gas transfer coefficient. Sensitivity studies using the streamlineaveraged model suggest that uncertainties in air-sea buoyancy fluxes in current climatologies result in significant uncertainty in estimates of Southern Ocean uptake of anthropogenic CO2 based on circulation and biogeochemistry models driven by, or brought into consistency with, the climatological fluxes. This uncertainty is sufficient to explain a significant amount of the spread in a recent model comparison study. INDEX TERMS: 4808 Oceanography: Biological and Chemical: Chemical tracers; 4806 Oceanography: Biological and Chemical: Carbon cycling; 4842 Oceanography: Biological and Chemical: Modeling; KEYWORDS: residual mean theory, Southern Ocean, transient tracers
Synthesis of 2‘-O-Methoxyethylguanosine Using a Novel Silicon-Based Protecting Group

A short and efficient synthesis of 2'-O-methoxyethylguanosine (8) is described. Central to this strategy is the development of a novel silicon-based protecting group (MDPSCl(2), 2) used to protect the 3',5'-hydroxyl groups of the ribose. Silylation of guanosine with 2 proceeded with excellent regioselectivity and in 79% yield. Alkylation of the 2'-hydroxyl group of 6 proceeded with methoxyethyl bromide and NaHMDS and afforded compound 7 in 85% yield, without any noticeable cleavage of the silyl protecting group and without the need to protect the guanine base moiety. Finally, deprotection of 7 was achieved using TBAF and produced 8 in 97% yield.
The Multi-Source Interference Task: an fMRI task that reliably activates the cingulo-frontal-parietal cognitive/attention network

In this protocol we describe how to perform the Multi-Source Interference Task (MSIT), a validated functional magnetic resonance imaging (fMRI) task that reliably and robustly activates the cingulo-frontal-parietal cognitive/attention network (CFP network) within individual subjects. The MSIT can be used to (i) identify the cognitive/attention network in normal volunteers and (ii) test its integrity in people with neuropsychiatric disorders. It is simple to perform, can be completed in less than 15 min and is not language specific, making it appropriate for children, adults and the elderly. Since its validation, over 100 adults have performed the task. The MSIT produces a robust and temporally stable reaction time interference effect (range 200-350 ms), and single runs of the MSIT have produced CFP network activation in approximately 95% of tested subjects. The robust, reliable and temporally stable neuroimaging and performance data make the MSIT a useful task with which to study normal human cognition and psychiatric pathophysiology.
Recurrence of idiopathic intracranial hypertension after weight loss: the carrot craver.

PURPOSE: To describe a patient with stable idiopathic intracranial hypertension whose papilledema worsened. METHOD: Case report. RESULTS: A patient with documented idiopathic intracranial hypertension had resolution of disc edema with weight loss. Recurrence of papilledema led to the discovery that she consumed large quantities of raw carrots to help maintain her weight. Her increased vitamin A levels normalized, and the disc edema resolved when she stopped eating carrots. CONCLUSION: Patients with idiopathic intracranial hypertension should be counseled regarding carrot intake.
Men Who Cheer

This study examines the maintenance of gender and sexuality within a female-dominated sport, focusing specifically on men who cheer. Data were collected at a northeastern Ohio university using focus group discussions and one-on-one interviews. The interviews and discussions provided themes regarding stigmatization of male cheerleaders, the need to project a heterosexual image, and methods of saving face. Findings indicate that the gender and sexuality of men who cheer are called into question. In order to affirm their gender and sexuality as masculine and heterosexual, the men engage in behavior that sexualizes women and desexualizes their relationships with men. Overall, the findings demonstrate how the patriarchal superstructure manifests in smaller institutions in society. Implications of these findings and areas of future research are further addressed within the study.
Sources of the Solar Wind at Ulysses during 1990-2006

The Ulysses spacecraft is now well into its third polar orbit around the Sun. Using stackplot displays, we summarize the wind speeds and interplanetary sector polarities recorded by Ulysses since its launch in 1990 and relate the observed patterns to the global evolution of open magnetic regions (coronal holes) over the solar cycle. We verify that the wind speeds are inversely correlated with the rate of flux-tube divergence in the corona, as derived from a current-free extrapolation of the measured photospheric field. We identify the source of each of the long-lived, high-speed streams encountered by Ulysses and discuss their formation, evolution, and rotational properties.
Women business angels: Insights from angel groups

Abstract Women have become a significant and growing financial power over the past 20 years and are developing an increasing presence in the angel market. However, there is a paucity of research on the role of women as angel investors. Do women angels have a tendency to invest in women entrepreneurs? What are the underlying incentives and motivations for women to become involved as angel investors? This survey-based research addresses these questions, and identifies some of the underlying implications of the findings on the current and future role of women as angel investors.
A structural analysis of hepatomegaly induced by a hormone-secreting tumor.

Abstract The hepatic growth observed in rats bearing transplantable hormone (ACTH, growth hormone, prolactin) secreting mammotropic tumors (MtT.F4) has been resolved into three components: (1) an increase in the size of individual parenchymal cells relative to the amount of DNA which they contain; (2) an increase in the DNA contents (ploidies) of the parenchymal cells and of their nuclei; and (3) an increase in the total number of parenchymal cells. As a result of all of these factors, the relative mass of the liver is increased to an extent greater than would have been expected to result from normal growth. Following removal of the tumors there is a reversal of all of these changes, except for a persisting increase in cell number and DNA content, and the resulting cells are smaller than normal. Whereas fatty metamorphosis and other degenerative changes occurred in the latter stages of tumor growth, the initial response was a striking hepatocellular enlargement and proliferation without significant fatty change. Fine structural studies of changes present in livers following 7 weeks of tumor growth showed many enlarged parenchymal cells containing proportional increases in all cytoplasmic constituents. Some cells, generally located at the lobule periphery, were heavily laden with fat vacuoles or showed almost complete fragmentation of the rough endoplasmic reticulum with formation of ribosome-studded vesicles containing material that was apparently secretory in character. Other fine structural changes included an increase in free ribosomes and polysomes and mitochondrial enlargement with the occasional appearance of very large bizarre mitochondrial forms. All changes, except possibly for a slight increase in relative liver mass, were prevented by adrenalectomy of the animal prior to tumor growth.
Associations of Acculturation and Country of Birth with Asthma and Wheezing in Mexican American Youths

Background: Mexican Americans have lower rates of asthma than other ethnic groups in the United States. Objective: To examine the relationship between country of birth and acculturation with asthma and wheezing among Mexican American youths. Methods: We used Chi-squared statistics and logistic regression analyses to determine the associations of country of birth and acculturation with asthma and wheezing among 1,770 Mexican Americans age 12–19 years who participated in the National Health and Nutrition Examination Survey 1999–2002. Results. Mexican American adolescents born in the United States and those with high acculturation levels reported significantly higher prevalence rates of asthma, wheezing, and hay fever than their peers with low acculturation levels and born in Mexico. In multivariate analyses, youths with a high acculturation level had a higher risk of asthma than those with a low acculturation level independent of country of birth. Highly acculturated youths born in the US had a higher risk ...
Compliance and durability in pressure garments.

This study examined the pressure volumetric characteristics (compliance) of Jobst (Jobst Institute, Toledo, Ohio), Barton-Carey (Barton-Carey Co., Perrysburg, Ohio), and Tubigrip (SePro Healthcare Inc., Moorestown, N.J.) pressure garments for arms after repeated saturation with lubricating substances and repeated washing/drying cycles. The three treatment groups were each composed of one sleeve from each of the manufacturers and were subjected to 20 washing/drying cycles. In addition, the sleeves in treatment groups 2 and 3 were saturated with cocoa butter and Lubriderm moisturizer, respectively, before each cycle. Circumferential measurements were taken on the proximal forearm of the sleeve at varying degrees of pressure with a Grafco standard sphygmomanometer (Graham Field Inc., Hauppauge, N.Y.) and a Gulick anthropometric tape measure (Creative Engineering, Plymouth, Mich.). Measurements were taken initially and after every fifth washing/drying cycle. Analysis of variance revealed significant results for the main effects and some interactions at the 0.01 level. Overall results showed little change in the Jobst and Barton-Carey garments, whereas the Tubigrip garments displayed an inconsistent pattern.
A microprocessor controled electronic distance meter

To realize fully the impact of electronic distance measurement on surveying technology, one must have had the experience of measuring a distance with a steel tape. However, an appreciation of the method used in making a distance measurement and the relative ease with which the measurement is made can be gained by understanding the basic operation of the HP-3805 electronic distance meter. So, this article begins by discussing distance meter operation, and then describes the microprocessor that was incorporated into the electronic distance meter. Next, the criteria considered in choosing the microprocessor are reviewed. Finally, we will point out the benefits of the union of a microprocessor and a distance meter to the design team, the manufacturer, and the customer.
Chimeric antigen receptors for the adoptive T cell therapy of hematologic malignancies

The genetic modification of autologous T cells with chimeric antigen receptors (CARs) represents a breakthrough for gene engineering as a cancer therapy for hematologic malignancies. By targeting the CD19 antigen, we have demonstrated robust and rapid anti-leukemia activity in patients with heavily pre-treated and chemotherapy-refractory B cell acute lymphoblastic leukemia (B-ALL). We demonstrated rapid induction of deep molecular remissions in adults, which has been recently confirmed in a case report involving a child with B-ALL. In contrast to the results when treating B-ALL, outcomes have been more modest in patients with chronic lymphocytic leukemia (CLL) or other non-hodgkin’s lymphoma (NHL). We review the clinical trial experience targeting B-ALL and CLL and speculate on the possible reasons for the different outcomes and propose potential optimization to CAR T cell therapy when targeting CLL or other indolent NHL. Lastly, we discuss the pre-clinical development and potential for clinical translation for using CAR T cells against multiple myeloma and acute myeloid leukemia. We highlight the potential risks and benefits by targeting these poor outcome hematologic malignancies.
Cholinergic receptors in aging and Alzheimer's disease

Although Alzheimer's disease (AD) is a disorder involving multiple neurotransmitter systems, the basal forebrain cholinergic system (Ch system) is severely and consistently affected in this condition. In both animals and man, the nature of age-associated alterations in the Ch system is unclear. In addition, available studies of cholinergic receptors in AD and aging are not consistent. In normal aging, the density of muscarinic cholinergic receptors (MCR) is reported to be either unchanged or decreased. In AD, increased, unchanged, or decreased densities have been reported. Recently, a subtype of MCR (M2), thought to be located presynaptically, has been reported to be reduced in neocortex and amygdala. In both AD and aging, nicotinic cholinergic receptors (NCR) have not been adequately studied. Our recent studies using [3H] acetylcholine and [3H] nicotine have demonstrated a reduction in NCR in AD. Possible explanations for some of the inconsistent findings are discussed, and directions for future studies are suggested.
Comparison of Methylation Procedures for Conjugated Linoleic Acid and Artifact Formation by Commercial (Trimethylsilyl)diazomethane

Four different methods for methylating conjugated linoleic acid (CLA) were compared. The HCl/MeOH and BF3/MeOH methods were tested under different time and temperature combinations. Increasing temperature and/or incubation time for either method decreased the cis-9,trans-11 and trans-10,cis-12 isomers, but trans-9,trans-11/trans-10,trans-12 isomers and artifacts (allylic methoxide) were increased. In addition, the triacylglyceride form of CLA was tested using the above methods and NaOMe at various temperatures for 20 min. The NaOMe did not generate methoxy artifacts. However, there were impurities in GC after methylation with NaOMe as well as with BF3/MeOH. The (trimethylsilyl)diazomethane method, which is a mild and easy alternative, was tested. Free forms of fatty acids were easily, but not completely, methylated by this method. Also, the method generated artifacts (trimethylsilyl CLA esters) and impurities (trimethylsilyl) that would interfere with short-chain fatty-acid analysis by GC. Keywords: Conju...
Size-specific ligands for RNA hairpin loops

The targeting of one mRNA in the transcriptome requires small molecules that bind with substantial affinity and specificity. As such, compounds with specificity for individual RNA secondary structural motifs could be useful for targeting RNA. Described herein is the synthesis of a combinatorial library of 105 dimers of deoxystreptamine and the subsequent identification of compounds with specificity for specific RNA hairpin loop sizes, including tetraloops and octaloops. Such compounds will be useful for the perturbation of RNA function in vivo.
The ESRD Uninsured Matter

Health-care insurance is the key to health-care access, yet the number of uninsured in the United States grows by a million persons per year and consists, in large part, of those who are financially unable to obtain medical coverage. Their unpaid medical bills add significantly to the cost of health insurance for those who do pay. Those without insurance receive care on a sporadic basis, and the risk of poor health-care outcomes is well established. The end-stage renal disease (ESRD) uninsured face unique problems related to chronicity of care and the system of chronic dialysis-care delivery. This article addresses the growing challenge of the ESRD uninsured in the United States and describes how the current system copes with the ESRD uninsured. More broadly, it discusses who the uninsured are (including undocumented immigrants), the health-care consequences of being without coverage, and how their care is currently financed. It also presents a health-care reform measure in Massachusetts designed to provide affordable insurance to those without coverage.
Grain Boundary Structure Evolution in Nanocrystalline Al by Nanoindentation Simulations

The nanoindentation of a columnar grain boundary (GB) network in nanocrystalline Al has been examined by atomistic simulation. The goal of this study was to gain fundamental understanding on the relationship between structure evolution at GBs and incipient plasticity for indenter tips significantly larger than the average grain size. The nanoindentation simulations were performed by quasicontinuum method at zero temperature. A GB network made of vicinal and high-angle tilt GBs was produced by generating randomly-oriented 5-nm grains at the surface of a 200 nm-thick film of Al. The major findings of this investigation are that (1) nanocrystalline GB networks profoundly impact on the nanoindentation response and cause significant softening effects at the tip/surface interface; (2) GB movement and deformation twins are found to be the predominant deformation modes in columnar Al, in association with shear band formation by GB sliding and intragranular slip, and crystal growth by grain rotation and coalescence; and (3) the cooperative processes during plastic deformation are dictated by the atomic-level redistribution of principal shear stresses in the material.
Covariant form for the conserved currents of the sine-Gordon and Liouville theories

Abstract A conserved covariant fourth rank tensor current J ; αβγ is constructed for these models both in flat and constant curvature space. For flat space, ∫ d x + J ++++ and its parity conjugate agree with well known results for the lowest grade sine-Gordon conserved charges. However potentially new charges such as ∫ d x + J +++− and ∫ d x + J +++ α ϵ αβ x β either vanish or fail to be conserved because J μαβγ is not symmetric in μ ↔ γ . There is one curious exception for sine-Gordon models in anti-de Sitter space.
Further evidence that ouabain-resistant variants induced by chemical carcinogens in transformable C3H/10T1/2 Cl 8 mouse fibroblasts are mutants.

Abstract Ouabain-resistant (Ouar) variants were induced in C3H/10T1/2 Cl 8 cells by the chemical carcinogens, N-methyl-N′-nitro-N-nitrosoguanidine (MNNG), N-acetoxy-N-2-acetylaminofluorene (N-AcO-AAF), and benzo[a]pyrene (BaP). The use of the Poisson calculation to determine Ouar variant frequencies gave more linear dose-response curves than when variant frequencies were calculated from the observed number of Ouar colonies. Increasing the Oua concentration from 3 to 6 mM decreased the frequency of Ouar variants. When cloned Ouar variants were mixed with wild-type cells, there was no metabolic cooperation and no loss of mutants when mock expression-time curves were determined. Ouar variants remained Ouar after prolonged cultivation in the absence of Oua. 86Rubidium (86Rb) uptake was at least 10-fold more resistant to inhibition by Oua in Ouar variants than in wild-type cells. In one Ouar clone, one-third of the 86Rb uptake was not inhibited by Oua concentrations as high as 10 mM, indicating that C3H/10T1/2 Cl 8 cells might be triploid at the Ouar locus. The relationship between the inhibition of 86Rb uptake and the cytotoxicity caused by the same concentration of Oua was the same for 2 Ouar clones and wild-type C3H/10T1/2 Cl 8 cells. Therefore, the Ouar variants detected by this assay are most likely true mutants possessing an altered Na+K+ transport system, the Na+K+Mg2+-activated adenosine triphosphate (ATPase), that is more resistant to Oua inhibition than the ATPase in wild-type cells.
The Laboratory as a Productivity and Citation Unit in the Publications of an Experimental-Psychology Specialty.

Five-hundred eighteen publications on the Pavlovian conditioning of the eyeblink reflex in humans were produced by 101 laboratories that examined human-eyeblink conditioning (HEC). Among low- and medium-productive labs, productivity was distributed in a Lotka-like fashion, although high-producing HEC labs were off the curve. The Lotka distribution for labs was flatter than that for a “complete count” of authors. Citations to publications of these 101 labs were obtained in reference lists of HEC publications from 1958–1985, with laboratory self-citations excluded. The frequency of citation by other HEC labs—both overall and adjusted to correct for unequal number of high- and low-productivity labs (see text)—showed high positive correlations with the productivity of the cited HEC lab. In a diachronic format we also examined the decline of references to the publications of laboratories that had become inactive. We related our findings to the idea that the laboratory is the source of production and the target of citation practices within a specialty. © 1992 John Wiley & Sons, Inc.
Structural organization of avian retrovirus integrase in assembled intasomes mediating full-site integration.

Abstract Retrovirus preintegration complexes (PIC) purified from virus-infected cells are competent for efficient concerted integration of the linear viral DNA ends by integrase (IN) into target DNA (full-site integration). In this report, we have shown that the assembled complexes (intasomes) formed in vitro with linear 3.6-kbp DNA donors possessing 3′-OH-recessed attachment (att) site sequences and avian myeloblastosis virus IN (4 nm) were as competent for full-site integration as isolated retrovirus PIC. The att sites on DNA with 3′-OH-recessed ends were protected by IN in assembled intasomes from DNase I digestion up to ∼20 bp from the terminus. Several DNA donors containing either normal blunt-ended att sites or different end mutations did not allow assembly of complexes that exhibit the ∼20-bp DNase I footprint at 14 °C. At 50 and 100 mm NaCl, the ∼20-bp DNase I footprints were produced with wild type (wt) U3 and gain-of-function att site donors for full-site integration as previously observed at 320 mm NaCl. Although the wt U5 att site donors were fully competent for full-site integration at 37 °C, the ∼20-bp DNase I footprint was not observed under a variety of assembly conditions including low NaCl concentrations at 14 °C. Under suboptimal assembly conditions for intasomes using U3 att DNA, DNase I probing demonstrated an enhanced cleavage site 9 bp from the end of U3 suggesting that a transient structural intasome intermediate was identified. Using a single nucleotide change at position 7 from the end and a series of small size deletions of wt U3 att site sequences, we determined that sequences upstream of the 11th nucleotide position were not required by IN to produce the ∼20-bp DNase I footprint and full-site integration. The results suggest the structural organization of IN at the att sites in reconstituted intasomes was similar to that observed in PIC.
Plastic collapse of general frames

Abstract A structural theory is presented for the large static plastic deformation of space frames composed of thin walled members. Displacements comparable to the overall structural dimensions are contemplated. The frame is considered to consist of an arbitrary number of beam elements connected at node points. The analysis assumes that plastic deformation is confined to idealized hinges located at the node points. As a basis for a general frame computer program, the equations for a beam element are derived as a relationship between appropriate generalized force and deformation rates. The structural constitutive theory employed for the plastic hinge includes biaxial bending, torsion, and axial extension. It accounts for reduction in the load carrying capacity of the hinge due to local deformation. Predicted force-deformation curves for a space frame are in good agreement with experimental results.
The changing contexts of the desertification debate

Abstract A great many debates have grown up around the notion of desertification as a process of degradation that affects the arid, semi-arid and sub-humid zones of the globe. A fundamental and continuing debate has been over whether desertification actually exists and, if so, how it might be defined, measured and assessed. Rather than simply review the evolution of these debates we examine the contexts in which they take place and how those contexts have contributed to the evolution of our understanding of the intertwined processes that contribute to desertification. The fact that these contexts have changed over time, combined with the fact that some of them are often ignored have both helped to sustain debate. We consider four contexts that frame much of the debate and consider what impact each has had: (1) changes in our understanding of climate variability; (2) changes in our understanding of vegetation responses to perturbation; (3) changes in our understanding of social processes, including household responses to economic perturbation; and (4) changes in our understanding of desertification as a political process or artifact.
Aging, long-distance running, and the development of musculoskeletal disability: A controlled study

Four hundred ninety-eight long-distance runners aged 50 to 72 years were compared with 365 community control subjects to examine associations of repetitive, long-term physical impact (running) with musculoskeletal disability and medical service utilization in a cross-section study. Runners had less physical disability than age-matched control subjects (p less than 0.01) and maintained more functional capacity (p less than 0.001) as measured by a modified Health Assessment Questionnaire Disability Index. Runners sought medical services less often, but one third of the visits that they did make were for running-related injuries. No differences were found between groups in conditions thought to predispose to osteoarthritis and musculoskeletal disability. Ligamentous laxity and family history of arthritis were similar in both groups. Runners demonstrated better cardiovascular fitness and weighed less. Differences persisted after adjustment for age, occupation, and sex, and after inclusion or exclusion of subjects with major medical problems. Musculoskeletal disability appeared to develop with age at a lower rate in runners (0.003 units per year versus 0.028) than in community control subjects, and the decreased rate was observed with both lower extremity and upper extremity functions. These data suggest positive effects of systematic aerobic running activity upon functional aspects of musculoskeletal aging.
Induction of differentiated phenotypes in melanoma cells by a combination of an adenosine 3',5'-cyclic monophosphate stimulating agent and D-alpha tocopheryl succinate.

Abstract The purpose of this investigation was to identify those agents and combinations of agents that help convert murine melanoma cells to cells of differentiated (normal-like) phenotype in culture. The agents used were 4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone (R020-1724), which is an adenosine 3′,5′-cyclic monophosphate (cAMP) phosphodiesterase inhibitor that has never been tested on melanoma cells in culture, and d-alpha tocopheryl succinate (vitamin E succinate), which has previously been shown to inhibit growth and induce morphological differentiation in melanoma cells. The results indicated that R020-1724 by itself inhibited growth, reduced survival, caused morphological differentiation and increased the melanin content (one of the biochemical differentiated functions) in melanoma cells. Vitamin E succinate had a similar effect on the melanoma cells, which supports past research on this vitamin. A combination of R20-1724 and vitamin E succinate had a significantly greater effect on the melanoma cells than either of the agents by themselves. The agents identified in this study may provide useful tools for studying the mechanisms of differentiation in melanoma cells.
Comparison of Analytical Theory with Brownian Dynamics Simulations for Small Linear and Circular DNAs

An approximate analytical theory is constructed for the optical anisotropy of a circular weakly bending filament. It is argued that such circles exhibit very nearly dynamical mean local cylindrical symmetry, despite their inherent curvature. This theory and the corresponding approximate analytical theory for weakly bending rods are tested by fitting each theory to the results of Brownian dynamics simulations, in which all of the relevant forces are included. A rigorous derivation is presented for the force arising from the torsion potential, which couples torsional strain to writhing and crankshaft motions, and a new more convenient expression is obtained. Simulations of equilibrium trajectories performed with and without this force show that it has no significant effect on the optical anisotropy of either circular or linear filaments with parameters appropriate for DNA. However, when large net torsional strains are introduced into planar circles, this force enormously enhances the rate at which twist is ...
A new canonical form of state-variable equations and its application in the determination of a mathematical model of an unknown system†

A new canonical form of state-variable equations is developed for a time-invariant linear system with a single input and a single output. This new representation of the system dynamics enables one to generate the state variables using the integrals of the input and the directly observable output. Another advantage of this new state-variable description is that the parameters of an unknown system can be evaluated with the help of theintegrals of the input and output. The proposed method of identification of the parameters is particularly advantageous to determine the state-variable model (or equivalently, the transfer function) of a stable system. Non-zero or unknown initial conditions are easily handled by a proper choice of the input function. Because the calculation of the unknown parameters involves the use of integrals the effect of any measurement noise tends to get suppressed. It is not necessary, theoretically at least, to assume the order of the system to bo identified. Of the (2n) unknown paramet...
The sorption of pyridine on SiOSiHCl2 monolayers on silica

Abstract Silica can be dehydroxylated by treatment with HSiCl 3 at 325°C. The resultant SiOSiHCl 2 monolayer will sorb pyridine at 22°C, forming Lewis, hydrogen-bonded and Bronsted surface species. The formation of the Lewis surface species was accompanied by a marked decrease of the intensity of the SiH stretching vibration band of the surface silane groups. All sorbed pyridine species are weakly held to the surface and could be removed by degassing briefly at 50°C. Infrared Fourier transform spectroscopy was used to follow the reactions.
A company-based framework for a software engineering course

The subject matter of a typical undergraduate software engineering course, while providing necessary background, can be quite dry. Team-based programming projects often complement the more theoretical textbook and lecture content by giving students valuable hands-on practice, albeit on a small scale and within a traditional classroom setting. This paper describes a company-based framework used in two semesters of a software engineering course. This approach incorporates a novel, collaborative framework to simulate the real-world experience of working for a medium-sized software design company or research laboratory, while giving students a vested interest in the overall outcome.
Costello syndrome with pancreatic islet cell hyperplasia

A 3-month-old boy with Costello syndrome (CS) developed respiratory distress and fatal arrhythmias. An autopsy showed cardiac hypertrophy, mild coarctation of the aorta, and pancreatic islet cell hyperplasia. To our knowledge, this is the first report of a pancreatic abnormality in CS. Islet cell hyperplasia has also been observed in leprechaunism, Beckwith-Wiedemann (BWS), and Simpson-Golabi-Behmel syndromes. The syndromes are thought to involve abnormal insulin or insulin-like growth factor (IGF) pathways. Clinical similarities among these disorders and CS, together with the finding of islet cell hyperplasia, suggest that they may be related.
Wave propagation in imperfectly periodic structures: A random evolution approach

After a brief review of some results pertaining to wave propagation in periodic structures and to random evolutions, we propose a random evolution model for wave propagation in a randomly disordered periodic structure. The model is investigated in the particular case of a two layer laminated composite with layers of random thicknesses. It is shown that there is at most one propagating frequency for Floquet waves of the average solution.