cssi/SciSciGPT-SciSciNet huggingface dataset:
Evaluation of right intraventricular dyssynchrony by two-dimensional strain echocardiography in patients with pulmonary arterial hypertension.

Background Right ventricular (RV) function has major prognostic implications for patients with pulmonary arterial hypertension (PAH). Intraventricular dyssynchrony might play an important role in RV dysfunction in these patients. Methods Thirty-six patients with PAH without right bundle branch block (mean age 44 ± 14 yr, 24 women) and 39 controls (mean age 43 ± 18 yr, 26 women) were evaluated. Global and segmental RV longitudinal deformation parameters were recorded by 2-dimensional strain echocardiography from apical 4-chamber views using a 6-segment RV model. The standard deviation of the heart rate–corrected intervals from QRS onset to peak strain for the 6 segments (RV-SD 6 ) was used to quantify right intraventricular dyssynchrony. Results RV-SD 6 was significantly higher in patients with PAH compared with controls (63 ± 21 vs 25 ± 15ms, P 6 was strongly correlated with RV fractional area change (β = −.519, P = .002), RV myocardial performance index (β = .427, P = .009), and RV global strain (β = .512, P = .002); in models controlling for RV systolic pressure, RV size, and QRS duration, RV-SD 6 was still an independent predictor of RV fractional area change (β = −.426, P = .005) and RV global strain (β = .358, P = .031). RV function was significantly worse in the subgroup of patients with PAH (n = 25) with RV-SD 6 > 55 ms (the upper 95% limit in controls). Conclusion Right intraventricular dyssynchrony, as quantified by 2-dimensional strain echocardiography, is prevalent in PAH and is associated with more pronounced RV dysfunction. The clinical implications of these findings remain to be determined in follow-up studies.
Peripherally inserted central venous catheter fracture and embolization to the lung

We report an adolescent patient with a peripherally inserted central venous catheter fracture and subsequent migration of the catheter fragment through the heart and into the lower lobe of the right lung. Physical findings were unremarkable for indications of this pulmonary embolization. With the increasing use of such devices for prolonged venous access, the practicing pediatric emergency physician should be aware of this potential complication.
Diverse albedos of small trans-neptunian objects

Discovery of trans-neptunian object (TNO) satellites and determination of their orbits has recently enabled estimation of the size and albedo of several small TNOs, extending the size range of objects having known size and albedo down into the sub-100 km range. In this paper we compute albedo and size estimates or limits for 20 TNOs, using a consistent method for all binary objects and a consistent method for all objects having reported thermal fluxes. As is true for larger TNOs, the small objects show a remarkable diversity of albedos. Although the sample is limited, there do not yet appear to be any trends relating albedo to other observable properties or to dynamical class, with the possible exception of inclination. The observed albedo diversity of TNOs has important implications for computing the size-frequency distribution, the mass, and other global properties of the Kuiper belt derived from observations of objects' apparent magnitudes and may also point the way toward an improved compositional taxonomy based on albedo in addition to color.
Race and ethnicity II Skin and other intimacies

The intimate turn in geography has centralized approaches to race and ethnicity which foreground bodily encounters. The quirky spatialities of intimacy, involving not just proximities but also distancing and borders, operate in racial and ethnic ‘contact zones’. Skin is one of these, and it is central to an understanding of race and ethnicity as arising through bodily encounters in places. Geographic scholarship emphasizing embodied racial and ethnic topics has highlighted processes of approximation, distancing, and bordering in race and ethnicity as lived events. Set within the intimate turn, this work has the potential to inform geographers and geographic scholarship with respect to criticality, the stickiness of place, and visceral geographies. In addition, the need to elucidate further the relationship between race and ethnicity is underscored.
Development of the nonverbal immediacy scale (NIS): Measures of self‐and other‐perceived nonverbal immediacy

In recent years nonverbal immediacy has received considerable attention from researchers concerned with instructional communication, interpersonal communication, and organizational communication. Unfortunately, the instruments used to measure nonverbal immediacy in these contexts sometimes have been problematic in terms of their reliability estimates. This research attempted to overcome this problem, or failing that, to identify the cause(s) of the reduced reliability. The research resulted in a scale with high reliability when used as either a self‐report or an other‐report measure. It was also found to be equally reliable across the contexts of instructional, interpersonal, and organizational communication. Content validity of the scale is good and an initial test of predictive validity produced a high validity correlation. Unexpected sex differences were observed in the results and these are discussed in this report.
The impact of retail establishments in hinterlands on the export role of retail establishments in rural places

Rural retail trade industries can serve an export function for and contribute to the economic growth of a rural place. The importance of a retail trade industry to the economy of a rural place depends on its market area. Since those market areas often extend into a place’s hinterlands, retail trade can effectively have an export component for the place itself. Yet empirical determination of the export role of a rural retail trade industry has been historically confounded by data limitations which limit testing for and identification of an industry’s market area. Using geographic information system tools to define variables for differing driving distances (as contrasted with circles defined by Euclidean distance) from a place, this paper tests for the market areas of seven retail trade industries in rural places and for the impact of retail trade in hinterlands on those market areas. This paper contributes to the relevant literature in three ways. First, it tests formally for a retail industry’s “market area driving time.” Prior articles which have incorporated distance into their analyses have not generally tested for the actual travel times more appropriate for such analyses. Second, it finds that not undertaking such testing might produce misleading results regarding the relationship between a place and the hinterlands in its market areas. Third, the regression results suggest subtlety in the export nature of rural retail trade, with some industries losing their export nature when competing businesses appear in hinterlands (Weak Export Retail industries) and other industries retaining their export nature under those circumstances (Strong Export Retail industries).
CD8+ Tregs in lupus, autoimmunity, and beyond.

While CD4+CD25high regulatory T cells (Tregs) have garnered much attention for their role in the maintenance of immune homeostasis, recent findings have shown that subsets of CD8+ T cells (CD8+ Tregs) display immunoregulatory functions as well. Both CD4+ Tregs and CD8+ Tregs appear impaired in number and/or function in several autoimmune diseases and in experimental animal models of autoimmunity, suggesting the possibility of immunotherapeutic targeting of these cells for improved management of autoimmune conditions. Our group has developed a strategy to induce CD8+ Tregs in autoimmune mice through the use of a tolerogenic self-peptide, and new information has been gained on the phenotype, function and role of induced CD8+ Tregs in autoimmunity. Here we present an overview of the role and mechanisms of action of CD8+ Tregs in autoimmunity, with a special focus on lupus. We also discuss the potential role of CD8+ Tregs in other diseases, including chronic infection and cancer.
Structuring argumentation in a social constructivist framework: A pedagogy with computer support

What we usually think of as higher order skills in argumentation can be profitably viewed as systematic structures for organizing and representing information. Standard terms like “line of argument”, “synthesis”, “analysis” and “draft” can be viewed as ways of constructing, storing, and accessing data in a social context — data structures for social communication. What makes argument difficult are the multiple structures that arguers have to construct and negotiate when reading and composing. In this paper, we describe the WARRANT project, a project designed to identify data structures of written argument and to design and implement computer tools to aid in the reading and design of argument.
Olfactory function and disease severity in chronic rhinosinusitis.

BACKGROUND Olfactory dysfunction is deemed to be a significant contributor to poor quality of life (QOL). However, little is known about the relationship of olfactory testing to other measures of disease burden in patients with chronic rhinosinusitis (CRS). In this study, we examine the relationship of olfactory function to computed tomography (CT) scores, endoscopy scores, and QOL measures in patients with CRS. METHODS A multi-institutional, cross-sectional analysis of 367 patients was performed. Several objective measures were collected: the Smell Identification Test, Lund-MacKay CT score, Lund-Kennedy endoscopy score, two validated disease-specific QOL instruments, the Rhinosinusitis Disability Index and the Chronic Sinusitis Survey, and a general health-related QOL instrument, the Medical Short Form-36. Analysis of variance was performed. Correlation coefficients were calculated. RESULTS Patients with olfactory dysfunction had significantly worse mean endoscopy scores (normosmics, 4.16 [+/- 3.97]; hyposmics, 6.26 [+/- 4.21]; anosmics, 9.61 [+/- 4.48]; p < 0.001) and significantly worse CT scores (normosmics, 9.11 [+/- 5.40]; hyposmics, 11.16 [+/- 5.96]; anosmics, 17.62 [+/- 5.37]; p < 0.001). Endoscopy scores were moderately correlated with olfactory scores (r = -0.46; 95% CI, -0.38, -0.54; p < 0.001). CT scores were moderately correlated with olfactory scores (r = -0.53; 95% CI, -0.45, -0.60; p < 0.001). Olfactory function was not correlated with disease-specific or general health-related QOL measures. CONCLUSION Although previous studies have suggested that olfactory impairment is associated with poor QOL, this study found no such correlation. In contrast, olfaction scores correlated well with other objective measures of CRS, namely, endoscopy and CT scores.
Effects of turbulence model constants on computation of confined swirling flows

The SIMPLE turbulence model procedure of Patankar (1980) is presently used to systematically assess the applicability of the standard k-epsilon turbulence model and one of its variations to decaying swirl prediction in developing turbulent pipe-flow. It is found that the trends and extent of the decaying tangential velocity are well-predicted by the standard k-epsilon model; the modified turbulence model results in slower decay, but with no substantial improvement over the standard model. 6 refs.
Fabrication and optical characterization of high-Q guided mode resonances in a graphite-lattice photonic crystal slab

Photonic-crystal slabs based on the graphite lattice have been fabricated in silicon-on-insulator and optically characterized. Guided mode resonances were measured with quality factors up to 9800 in air and up to 8600 in water.
A note on adaptive boiler tube pulling

This paper develops an adaptive algorithm for determining boiler tube pulling strategies by postulating a Beta prior on the probability that an individual tube is defective. This prior is updated according to Bayes' Rule as a result of the sample obtained during the tube pulling process.
Structure-guided engineering of human thymidine kinase 2 as a positron emission tomography reporter gene for enhanced phosphorylation of non-natural thymidine analog reporter probe

Positron emission tomography (PET) reporter gene imaging can be used to non-invasively monitor cell-based therapies. Therapeutic cells engineered to express a PET reporter gene (PRG) specifically accumulate a PET reporter probe (PRP) and can be detected by PET imaging. Expanding the utility of this technology requires the development of new non-immunogenic PRGs. Here we describe a new PRG-PRP system that employs, as the PRG, a mutated form of human thymidine kinase 2 (TK2) and 2'-deoxy-2'-18F-5-methyl-1-β-L-arabinofuranosyluracil (L-18F-FMAU) as the PRP. We identified L-18F-FMAU as a candidate PRP and determined its biodistribution in mice and humans. Using structure-guided enzyme engineering, we generated a TK2 double mutant (TK2-N93D/L109F) that efficiently phosphorylates L-18F-FMAU. The N93D/L109F TK2 mutant has lower activity for the endogenous nucleosides thymidine and deoxycytidine than wild type TK2, and its ectopic expression in therapeutic cells is not expected to alter nucleotide metabolism. Imaging studies in mice indicate that the sensitivity of the new human TK2-N93D/L109F PRG is comparable with that of a widely used PRG based on the herpes simplex virus 1 thymidine kinase. These findings suggest that the TK2-N93D/L109F/L-18F-FMAU PRG-PRP system warrants further evaluation in preclinical and clinical applications of cell-based therapies.
Prolapse and Incontinence Surgery in Older Women

Purpose: Pelvic floor disorders including urinary incontinence, pelvic organ prolapse and fecal incontinence are common problems encountered by the older woman. With the increasing population of older American women urologists and gynecologists can expect to provide evaluation and treatment of these conditions with increasing frequency. These conditions are amenable to medical and surgical therapies.Materials and Methods: Contemporary articles (2003 to the present) that included older women undergoing urogynecological surgery were included in this review. Current data on morbidity, mortality and/or surgical outcomes are presented with evidence based preoperative, intraoperative and postoperative surgical management strategies.Results: Older women undergoing pelvic floor surgery can expect operative risks as well as subjective and objective anatomical and quality-of-life outcomes similar to those of younger women.Conclusions: The decision for surgical intervention for the treatment of pelvic floor disorder...
Seventy-five years of comorbidity research.

Objective:As part of the 75th anniversary edition of the Journal of Studies on Alcohol and Drugs, this article reviews research on the relationship between mental disorders and substance use disorders (“comorbidity”) from 1940—the journal’s inception—to the present.Method:First, a survey of the titles and abstracts of all articles published in the journal was used to identify those articles pertaining to comorbidity. Seminal and representative works from this set of articles and a limited selection of articles from other journals were included in the review.Results:The early psychosocial research emphasized psychoanalytic formulations of alcohol use as a defensive symptom, which informed the early experimental research on the tension-reducing properties of alcohol. The “cognitive revolution,” occurring in the 1970s, enabled an expansion of the tension-reduction theory to include a central role for mental processes (e.g., alcohol expectancies) in promoting drinking to cope with negative affectivity. The ea...
Hydrocortisone enhancement of insulin's action on macromolecular synthesis in MCF-7 cells

Abstract In MCF-7 human breast cancer cells, insulin stimulated the rate of [ 3 H]uridine incorporation into RNA, [ 3 H]thymidine incorporation into DNA, and [ 3 H]leucine incorporation into protein. In addition, hydrocortisone appeared to augment the effect of insulin, by further increasing the rate of [ 3 H] uridine incorporation into RNA and [ 3 H]thymidine incorporation into DNA. A significant increase in the total amount of DNA and protein was present in cultures treated with insulin compared to untreated controls. Hydrocortisone was shown to augment the insulin effect on total protein accumulation and total RNA accumulation in MCF-7 cells.
Photodynamic therapy in the management of resistant lower urinary tract carcinoma.

Twenty-three patients with resistant transitional cell carcinoma (TCC) of the bladder and posterior urethra had photodynamic therapy (PDT). Seventy-two hours after an intravenous injection with 2 mg/kg of the photosensitizer dihematoporphyrin ether (DHE) (Photofrin 11, Photomedica, Raritan, NJ), each patient received cystoscopic light treatment. The light dose to the whole bladder using the bulb diffuser ranged from 5 to 60 J/cm2; power density ranged from 9 to 22 mW/cm2. The focal light dose ranged from 100 to 200 J/cm2 at a power density from 100 to 200 mW/cm2. To treat the urethra, a diffuser fiber was used to deliver 200 to 400 J/linear cm at a power of 110 to 300 mW/cm. In the 19 of 23 patients who were treated for resistant superficial TCC, 83396 of the tumors had responded at the initial follow-up evaluation. Seven patients had a complete response and 10 had a partial response. Three of 19 patients who received inadequate light treatment failed to respond. Control of intractable gross hematuria was the only benefit for patients with locally invasive disease (rT2). Irritating lower urinary tract symptoms that varied in severity and duration occurred in all patients. Four patients experienced bladder shrinkage, which did not resolve. Although the light and drug doses remain to be determined, a whole bladder light dose of 15 to 20 J/cm2 with a drug dose of 2 mg/kg seems to be effective enough without producing permanent adverse effects in the bladder. Cancer 60:3113-3119, 1987.
Jahn–Teller distortions in the electronically excited states of sym-triazine

Electronic structure of the low-lying excited states of sym-triazine is analysed. Excitation energies are computed at the equilibrium ground state geometry and at the geometry of the cation. Full geometry optimisations of the selected excited states were performed, and the magnitude of the Jahn–Teller distortions in these states was quantified. Analysis of the electronic structure of these states offers a simple recipe for predicting the symmetry of the equilibrium geometries by a single point calculation of the vertical excitations. Whereas the states derived from excitations between a degenerate pair and a non-degenerate orbital form a familiar two-state conical intersection and are always distorted by virtue of the Jahn–Teller theorem, the states derived from the excitations between two pairs of degenerate orbitals form a more complicated glancing-like manifold characterised by negligible Jahn–Teller linear terms. Our analysis shows that regardless of the degeneracy pattern in these four-state manifold...
Automating energy management in green homes

Homes powered fully or partially by renewable sources such as solar are becoming more widely adopted, however energy management strategies in these environments are lacking. This paper presents the first results of a study that explores home automation techniques for achieving better utilization of energy generated by renewable technologies. First, using a network of off-the-shelf sensing devices, we observe that energy generation and consumption in an off-grid home is both variable and predictable. Moreover, we find that reactive energy management techniques are insufficient to prevent critical battery situations. We then present a recommendation based system for helping users to achieve better utilization of resources. Our study demonstrates the feasibility of three recommendation components: an early warning system that allows users of renewable technologies to make more conservative decisions when energy harvested is predicted to be low; a task rescheduling system that advises users when high-power appliances such as clothes dryers should be run to optimize overall energy utilization; and an energy conservation system that identifies sources of energy waste and recommends more conservative usage.
Theory of scattering of elastic waves from flat cracks of arbitrary shape

Abstract A method, based on a boundary-integral representation of the elastic displacement, for calculating crack-opening-displacements on a flat crack of arbitrary shape and for incident elastic waves of arbitrary direction, polarization, and wavelength is developed and illustrated by application to Rayleigh scattering from two families of crack shapes. The crack-opening-displacement is expanded in a truncated complete set of functions on the crack surface. This transforms the boundary-integral representation into a matrix equation with rank three times the order of the truncation. This matrix equation has the properties that it can be expressed as the result of an extremum principle with respect to variations of the expansion coefficients of the crack-opening-displacement (thus converges as the truncation order increases) and the matrix kernel (which must be inverted) is positive definite. A conclusion drawn is that only very accurate experiments can distinguish a flat crack of general shape from a penny-shaped crack by long-wavelength elastic-wave scattering.
Experimental models for identifying modifiers of polyglutamine-induced aggregation and neurodegeneration.

Huntington’s disease (HD) typifies a class of inherited neurodegenerative disorders in which a CAG expansion in a single gene leads to an extended polyglutamine tract and misfolding of the expressed protein, driving cumulative neural dysfunction and degeneration. HD is invariably fatal with symptoms that include progressive neuropsychiatric and cognitive impairments, and eventual motor disability. No curative therapies yet exist for HD and related polyglutamine diseases; therefore, substantial efforts have been made in the drug discovery field to identify potential drug and drug target candidates for disease-modifying treatment. In this context, we review here a range of early-stage screening approaches based in in vitro, cellular, and invertebrate models to identify pharmacological and genetic modifiers of polyglutamine aggregation and induced neurodegeneration. In addition, emerging technologies, including high-content analysis, three-dimensional culture models, and induced pluripotent stem cells are increasingly being incorporated into drug discovery screening pipelines for protein misfolding disorders. Together, these diverse screening strategies are generating novel and exciting new probes for understanding the disease process and for furthering development of therapeutic candidates for eventual testing in the clinical setting.
The effects of depressive symptoms and anxiety on quality of life in patients with heart failure and their spouses: testing dyadic dynamics using Actor-Partner Interdependence Model.

Abstract Background Depressive symptoms and anxiety are common in heart failure patients as well as their spousal caregivers. However, it is not known whether their emotional distress contributes to their partner's quality of life (QoL). This study examined the effect of patients' and partners' depressive symptoms and anxiety on QoL in patient–spouse dyads using an innovative dyadic analysis technique, the Actor–Partner Interdependence Model (APIM). Method A total of 58 dyads (patient: 43% in males, mean age 62 years, mean ejection fraction 34% ±11, 43% in New York Heart Association III–IV) participated in the study. Depressive symptoms and anxiety were assessed using the Brief Symptom Inventory. QoL was assessed using the Minnesota Living with Heart Failure Questionnaire. Dyadic data were analyzed using the APIM with distinguishable dyad regression model. In APIM, actor effect is the impact of a person's emotional distress on his/her own QoL. Partner effect is the impact of a person's emotional distress on his/her partner's QoL. Result Depressive symptoms exhibited actor effect of both patients ( P P P Conclusion Interventions to reduce depression and anxiety and to improve patients' QoL should include both patients and spouses.
The structure of nasturtium amyloid

Abstract Nasturtium amyloid contains residues of d -glucose, d -xylose, and d -galactose in the molar proportions of 3:2:1, and all of them are pyranoid. The isolation of cellobiose and cellotetraose led to the conclusion that the main chain of this amyloid is a chain of the cellulose type. There are two branches per six glycosidic residues. If the main chain of the amyloid is, indeed, of the cellulose type, there are two branches per three d -glucose residues of the main chain. One would be a single d -galactose residue joined α(?)- d -Gal-(1→6)- d -G, and the other, α(?)- d -Xyl-(1→2)-α- d -Xyl-(1→6)- d -G. Isoprimeverose (6-O-α- d -xylopyranosyl- d -glucose) was obtained by partial hydrolysis of the amyloid, together with a tetrasaccharide composed of 2 d -glucose residues and 2 d -xylose residues, and a pentasaccharide composed of 3 d -glucose residues and 2 d -xylose residues. A repeating unit composed of six monosaccharide residues is proposed for the amyloid. The structural similarity of nasturtium amyloid and the tamarind-seed amyloid (tikernose) is discussed.
Didaktik of music. A German concept and its comparison to American music pedagogy

Didaktik of music is the science and art of teaching music in terms of determining goals, contents and methods. It is both a scholarly field of research and a teacher’s craft. Didaktik raises issues which neither curriculum research nor pedagogical methodology address in the same way. The main intent of this article is to present important issues concerning the German Didaktik of music, and to make comparisons to the approaches in the United States. By framing Didaktik in view of American music education as a prominent and familiar system, both practical and theoretical issues may be clarified. The concept of a comparative Didaktik of music is also introduced, allowing for more specific questions of pedagogy and curriculum to be raised which do not feature in studies to date.
Clinicians' Guide to New Tools and Features of PubMed

Practicing clinicians need to have the skills required to obtain up-to-date medical information to address both the expansion of scientific knowledge and patients' increasing use of the Internet. PubMed (www.pubmed.gov) allows clinicians free access to the largest biomedical resource available. This article is the third in a Mayo Clinic Proceedings series designed specifically to help clinicians unlock the tools and information available through this valuable resource.
Investigation into the relationship between the gravity vector and the flow vector to improve performance in two-phase continuous flow biodiesel reactor

Abstract The following study analyzes the performance of a continuous flow biodiesel reactor/separator. The reactor achieves high conversion of vegetable oil triglycerides to biodiesel while simultaneously separating co-product glycerol. The influence of the flow direction, relative to the gravity vector, on the reactor performance was measured. Reactor performance was assessed by both the conversion of vegetable oil triglycerides to biodiesel and the separation efficiency of removing the co-product glycerol. At slightly elevated temperatures of 40-50 °C, an overall feed of 1.2 L/min, a 6:1 M ratio of methanol to vegetable oil triglycerides, and a 1–1.3 wt.% potassium hydroxide catalyst loading, the reactor converted more than 96% of the pretreated waste vegetable oil to biodiesel. The reactor also separated 36–95% of the glycerol that was produced. Tilting the reactor away from the vertical direction produced a large increase in glycerol separation efficiency and only a small decrease in conversion.
The Shift from Dating to Hooking up in College: What Scholars Have Missed

In recent years, research has been building that suggests dating has been replaced by hooking up as the dominant way for heterosexual students to get together on college campuses. Although recent studies have documented the phenomenon of hooking up, there is evidence that this behavior was likely in place long before it was recognized in the literature. Yet, for the past several decades, scholars have continued to examine ‘dating’ among college students. This calls into question whether scholars missed a fundamental shift in how heterosexual men and women form sexual and romantic relationships on campus. In this paper, I will (i) review the major findings on hooking up, (ii) explain the differences between traditional dating and hooking up, (iii) explore when traditional dating declined and hooking up emerged on the college campus, and (iv) discuss the effect of this shift on the literature.
Court and spark: electric signals in the courtship and mating of gymnotoid fish

Abstract By mimicking tropical rainy season conditions in aquaria, we stimulated two species of gymnotoid electric fish, Eigenmannia virescens and Apteronotus leptorhynchus , to spawn in captivity. Their courtship activity, breeding behaviour and electric social communication were monitored in several groups over 2 years. Groups of both species established dominance hierarchies correlated with electric organ discharge frequency, aggressiveness and size. Spawning was preceded by several nights of courtship during which the male modulated its electric organ discharge to produce ‘chirps’. Continual bouts of chirping lasted for hours on evenings prior to spawning. These electrical signals play a significant role in courtship and spawning, as gravid E. virescens females could be stimulated to spawn by playing back into the tank a tape recording of male courtship chirps. In both species the chirp invovves a slight increase in frequency followed by a cessation of the dominant frequency. This suggests a common mode of signal production in these two different genera of fish. Chirps are short and abrupt during aggressive encounters, but assume a softer and more raspy quality during courtship.
Acetaminophen-induced suppression of hepatic AdoMet synthetase activity is attenuated by prodrugs of L-cysteine.

Abstract Administration of acetaminophen (ACP, 400 mg/kg, i.p.) to fasted, male Swiss-Webster mice caused a rapid 90% decrease in total hepatic glutathione (GSH) and a 58% decrease in mitochondrial GSH by 2 h post ACP. This was followed by a time-dependent decrease (72%) in hepatic AdoMet synthetase activity and rise in plasma ALT levels (>10 000 U/l) at 24 h post ACP treatment. AdoMet synthetase activity was maintained at 82, 78 and 60% of controls, respectively, by the cysteine prodrugs PTCA, CySSME and NAC. Total hepatic and mitochondrial GSH levels were also protected from severe ACP-induced depletion by CySSME and MTCA. These results suggest that the maintenance of GSH homeostasis by cysteine prodrugs can protect mouse hepatic AdoMet synthetase, a sulfhydryl enzyme whose integrity is dependent on GSH, as well as the liver itself from the consequences of oxidative stress elicited by toxic metabolites of xenobiotics.
Collagen fiber disruption occurs independent of calcification in clinically explanted bioprosthetic heart valves.

The durability of bioprosthetic heart valves (BHV) is severely limited by tissue deterioration, manifested as calcification and mechanical damage to the extracellular matrix. Extensive research on mineralization mechanisms has led to prevention strategies, but little work has been done on understanding the mechanisms of noncalcific matrix damage. The present study tested the hypothesis that calcification-independent damage to the valvular structural matrix mediated by mechanical factors occurs in clinical implants and could contribute to porcine aortic BHV structural failure. We correlated quantitative assessment of collagen fiber orientation and structural integrity by small angle light scattering (SALS) with morphologic analysis in 14 porcine aortic valve bioprostheses removed from patients for structural deterioration following 5-20 years of function. Calcification of the explants varied from 0 (none) to 1+ (minimal) to 4+ (extensive), as assessed radiographically. SALS tests were performed over entire excised cusps using a 0.254-mm spaced grid, and the resultant structural information used to generate maps of the local collagen fiber damage that were compared with sites of calcific deposits. All 42 cusps showed clear evidence of substantial noncalcific structural damage. In 29 cusps that were calcified, structural damage was consistently spatially distinct from the calcification deposits, generally in a distribution similar to that noted in porcine BHV subjected to in vitro durability testing. Our results suggest a mechanism of noncalcific degradation dependent on cuspal mechanics that could contribute to porcine aortic BHV failure.
Effective Charge Carrier Lifetime in Silicon p-i-n Junction Detectors

An estimate of the effective charge carrier lifetime can be obtained from a determination of the collection efficiency as a function of the transit time for charge carriers produced by incident short-range radiation in a p-i-n junction detector. The results of this method have the advantage of being independent of both the charge carrier mobility and the depletion depth of the detector. Effective lifetimes as low as a few microseconds (?e) for electrons produced by natural alpha particles have been observed in several 2 mm thick lithium-compensated silicon detectors operating at room temperature. No significant bias dependent windows which might cause misleading interpretation of the results were observed. Window effects were investigated by measuring the changes in pulse height of detector output signals initiated by natural alpha particles incident on the detectors at angles up to 45 degrees. The electron lifetimes were observed to decrease when the detector was operated at liquid nitrogen temperature. The short effective lifetimes that can occur in lithium-compensated silicon set a lower limit on the field strengths that must be maintained for efficient charge collection in thick p-i-n junction detectors. Effective hole lifetimes can also be obtained using this technique but with the present geometry of lithium-compensated silicon detectors this measurement is more difficult if short-range particles are used. The effects of charge carrier lifetime and amplifier pulse rise and fall times on the observed radiation-induced pulse shapes are discussed.
Metal-Modified Base Pairs Involving Different Donor Sites of Purine Nucleobases: trans-[a2Pt(7,9-DimeG-N1)(9-EtGH-N7)]2+ and trans-[a2Pt(7,9-DimeG-N1)(9-EtG-N7)]+ (a = NH3 or CH3NH2; 9-EtGH = 9-Ethylguanine; 7,9-DimeG = 7,9-Dimethylguanine). Possible Relevance to Metalated DNA Triplex Structures

The X-ray crystal structures of four mixed-nucleobase complexes 1a, 1b, 2, and 4 of trans-a2PtII (a = NH3 or CH3NH2) with N1-bonded 7,9-dimethylguanine (7,9-DimeG) and N7-bonded 9-ethylguanine (9-EtGH) are reported. The compounds are discussed in terms of their possible model character for platinated nucleobase triplets of the pu × pu·pym (pu = purine, pym = pyrimidine) type and are compared with known guanine·guanine pairs. Structural differences resulting from a “metal modification” have been studied, as have been stacking and H bonding motifs. 1a and 1b are two modifications of the same compound, trans-[(NH3)2Pt(7,9-DimeG)(9-EtGH)](ClO4)2·H2O. X-ray data for 1a: orthorhombic, Pca21, a = 13.833(3) A, b = 14.357(3) A, c = 13.293(3) A, Z = 4, R = 0.027. 1b: monoclinic, P21/n, a = 13.987(3) A, b = 12.582(3) A, c = 15.613(3) A, β = 104.61(3)°, Z = 4, R = 0.034. trans-[(CH3NH2)2Pt(7,9-DimeG)(9-EtGH)](ClO4)2 (2): orthorhombic, Pca21, a = 13.886(1) A, b = 14.698(1) A, c = 13.008(3) A, Z = 4, R = 0.034. tran...
Experimental Results and Bifurcation Analysis on Scaled Feedback Control for Subsonic Cavity Flows

In this paper, we present the latest results of our ongoing research activities in the development of reduced- order models based feedback control of subsonic cavity flows. The model was developed using the Proper Orthogonal Decomposition of Particle Image Velocimetry images in conjunction with the Galerkin projection of the Navier-Stokes equations onto the resulting spatial eigenfunctions. Stochastic Estimation method was used to obtain the state estimation of the Galerkin system from real time surface pressure measurements. A linear-quadratic optimal controller was designed to reduce cavity flow resonance and tested in the experiments. Real-time implementation shows a significant reduction of the sound pressure level within the cavity, with a remarkable attenuation of the resonant tone and a redistribution of the energy into various modes with lower energy levels. A mathematical analysis of the performance of the LQ control, in agreement with the experimental results, is presented and discussed.
Magnetic field-effects in bipolar, almost hole-only and almost electron-only tris-(8-hydroxyquinoline) aluminum devices

We present magnetoconductivity and magnetoluminescence measurements in sandwich devices made from the $\ensuremath{\pi}$-conjugated molecule tris-(8-hydroxyquinoline) aluminum $({\text{Alq}}_{3})$ and demonstrate effects of more than 25% and 50% magnitude, respectively. These effects are known to be caused by hyperfine coupling in pairs of paramagnetic species, and it is often assumed that these are electron-hole pairs. However, we show that the very large magnitude of the effect contradicts present knowledge of the electron-hole pair recombination processes in electroluminescent $\ensuremath{\pi}$-conjugated molecules and that the effect persists even in almost hole-only devices.
The case of AC stress in the hot-carrier effect

During ac hot-carrier stress, the direction of the transient current flow is demonstrated to be important in device degradation as well as the amount of substrate current generated in transient periods.
Seasonal N2 fixation by cool-season pulses based on several15N methods

Accurate estimates of N2 fixation by legumes are requisite to determine their net contribution of fixed N2 to the soil N pool. However, estimates of N2 fixation derived with the traditional15N methods of isotope dilution and AN value are costly.
Innovations in design and delivery of chemotherapy for brain tumors.

Despite decades of laboratory investigation and promising chemotherapy responses shown in xenograft models, survival for patients with central nervous system (CNS) tumors remains suboptimal and continues to pose a challenge in therapeutic oncology. This is exemplified in recent trends in cancer mortality in children and adults. Although the overall rate of deaths caused by cancer in children less than 15 years of age decreased between 1973 to1995, proportion of deaths caused by CNS tumors increased from 18% to 30% during the same period [1]. Similarly, survival for adults with malignant gliomas is dismal, with fewer than 10% of patients with glioblastoma multiforme alive 1 year after diagnosis. Although surgery and radiotherapy have long been established as treatment modalities of patients with braintumors,theroleofchemotherapyinsuchpatients is far from certain. Nevertheless, it has continued to play a significant part in the therapeutic armamentarium against these tumors in the last several decades andmighthavecontributed to disease stabilization and cure of some patients with brain tumors [2,3]. Concurrently, it has become obvious that a significant proportion of patients with brain tumors also suffer progressive disease during or following chemotherapy. The causes for such therapeutic failure have been explored and reported extensively. Invariably, the lack of response to chemotherapy has been caused by the presence of the blood–brain barrier and drug resistance [4–6]. This article initially discusses factors that contribute to chemotherapy failure followed by a discussion of recent advances in design and delivery of chemotherapy that have attempted to overcome some of these obstacles and improve antitumor responses and survival in patients with brain tumors.
Victimization, Parenting, and Externalizing Behavior Among Latino and White Adolescents

Given the large number of adolescents who have externalizing behavior problems and the increasing ethnic heterogeneity in many societies, it is important to examine whether the mechanisms underlying externalizing behavior are different among diverse groups. We specified separate models for ethnic groups and tested whether gender moderated the effect of victimization experiences and parent–child characteristics on externalizing behavior. The sample included 167 Latino and 625 White adolescents ages 10–17. For Latino adolescents, parental physical assault was related to more externalizing behavior for males and for females. More parental conflict and more criticism were related to less externalizing behavior for Latino females but not for Latino males. For White adolescents, all types of victimization (by parents, by siblings, by peers, witnessing domestic assault) and more parental conflict were related to more externalizing for males and for females. More monitoring was related to less externalizing behavior for White males but not for White females or for Latino adolescents. The intersection of ethnicity and gender may be important when examining adolescents’ externalizing behavior.
Minimum buffered routing with bounded capacitive load for slew rate and reliability control

In high-speed digital VLSI design, bounding the load capacitance at gate outputs is a well-known methodology to improve coupling noise immunity, reduce degradation of signal transition edges, and reduce delay uncertainty due to coupling noise. Bounding load capacitance also improves reliability with respect to hot-carrier oxide breakdown and AC self-heating in interconnects, and guarantees bounded input rise/fall times at buffers and sinks. This paper introduces a new minimum-buffer routing problem (MBRP) formulation which requires that the capacitive load of each buffer, and of the source driver, be upper-bounded by a given constant. Our contributions are as follows: We give linear-time algorithms for optimal buffering of a given routing tree with a single (inverting or noninverting) buffer type. For simultaneous routing and buffering with a single noninverting buffer type, we prove that no algorithm can guarantee a factor smaller than 2 unless P=NP and give an algorithm with approximation factor slightly larger than 2 for typical buffers. For the case of a single inverting buffer type, we give an algorithm with approximation factor slightly larger than 4. We give local-improvement and clustering based MBRP heuristics with improved practical performance, and present a comprehensive experimental study comparing the runtime/quality tradeoffs of the proposed MBRP heuristics on test cases extracted from recent industrial designs.
Nonspecific white matter degeneration following traumatic brain injury

Morphometric analysis of magnetic resonance (MR) scans in 88 traumatic brain injury (TBI) patients demonstrated significantly larger ventricle-to-brain ratios (VBR) and temporal horn volumes, and significantly smaller fornix-to-brain ratios (FBR) and corpus callosum (CC) area measurements, compared to 73 controls. Additionally, TBI patients were grouped according to Glasgow Coma Scale (GCS) for a within-TBI sample comparison so that severity of injury on brain morphology could be examined. The severe TBI group (GCS = 3–6) differed from the mild and moderate injury groups on measures of the internal capsule, VBR, temporal horn volume, and CC. In a separate analysis wherein the TBI subjects were grouped by degree of fornix atrophy, the group with the smallest fornix size demonstrated the lowest memory performance. Furthermore, anatomic measures correlated with severity of injury, and tests of memory and motor function. Results demonstrate the diffuse nature of degeneration in TBI with more severe injury, and that quantified MR identified morphologic changes relate to neuropsychological outcome. (JINS, 1995, 1, 17–28.)
Effect of sensory feedback from the proximal upper limb on voluntary isometric finger flexion and extension in hemiparetic stroke subjects.

This study investigated the potential influence of proximal sensory feedback on voluntary distal motor activity in the paretic upper limb of hemiparetic stroke survivors and the potential effect of voluntary distal motor activity on proximal muscle activity. Ten stroke subjects and 10 neurologically intact control subjects performed maximum voluntary isometric flexion and extension, respectively, at the metacarpophalangeal (MCP) joints of the fingers in two static arm postures and under three conditions of electrical stimulation of the arm. The tasks were quantified in terms of maximum MCP torque [MCP flexion (MCPflex) or MCP extension (MCPext)] and activity of targeted (flexor digitorum superficialis or extensor digitorum communis) and nontargeted upper limb muscles. From a previous study on the MCP stretch reflex poststroke, we expected stroke subjects to exhibit a modulation of voluntary MCP torque production by arm posture and electrical stimulation and increased nontargeted muscle activity. Posture 1 (flexed elbow, neutral shoulder) led to greater MCPflex in stroke subjects than posture 2 (extended elbow, flexed shoulder). Electrical stimulation did not influence MCPflex or MCPext in either subject group. In stroke subjects, posture 1 led to greater nontargeted upper limb flexor activity during MCPflex and to greater elbow flexor and extensor activity during MCPext. Stroke subjects exhibited greater elbow flexor activity during MCPflex and greater elbow flexor and extensor activity during MCPext than control subjects. The results suggest that static arm posture can modulate voluntary distal motor activity and accompanying muscle activity in the paretic upper limb poststroke.
Extending SDARTS: extracting metadata from web databases and interfacing with the open archives initiative

SDARTS is a protocol and toolkit designed to facilitate metasearching. SDARTS combines two complementary existing protocols, SDLIP and STARTS, to define a uniform interface that collections should support for searching and exporting metasearch-related metadata. SDARTS also includes a toolkit with wrappers that are easily customized to make both local and remote document collections SDARTS-compliant. This paper describes two significant ways in which we have extended the SDARTS toolkit. First, we have added a tool that automatically builds rich content summaries for remote web collections bym probing the collections with appropriate queries. These content summaries can then be used by a metasearcher to select over which collections to evaluate a given query. Second, we have enhanced the SDARTS toolkit so that all SDARTS-compliant collections export their metadata under the emerging Open Archives Initiative (OAI) protocol. Conversely, the SDARTS toolkit now also allows all OAI-compliant collections to be made SDARTS-compliant with minimal effort. As a result, we implemented a bridge between SDARTS and OAI, which will facilitate easy interoperability among a potentially large number of collections. The SDARTS toolkit, with all related documentation and source code, is publicly available at http://sdarts.cs.columbia.edu.