cssi/SciSciGPT-SciSciNet huggingface dataset:
Intussusception following resection of Wilms tumor

Abstract Postoperative intussusception is a documented complication of pediatric surgical and pediatric urologic abdominal operations. In contrast to “Primary” intussusception's triad of crampy abdominal pain, palpable abdominal mass, and “currant jelly” stools, postoperative intussusception is generally characterized by abdominal pain and vomiting. An abdominal mass is not usually palpable, and few children have bloody stools. Proper diagnosis and treatment may be delayed because of similar abdominal symptoms in children who may be receiving radiation and chemotherapy, or with prolonged ileus. Two children operated on for Wilms tumor demonstrate the need for awareness of this potential problem in the postoperative patient.
Receptivity Attitudes and the Occupational Attainment of Male and Female Immigrant Workers

This paper seeks to extend assimilation scholarship by focusing on the impact ofimmigrant receptivity attitudes. We test the hypotheses that receptivity attitudestoward immigrants held by citizens of metropolitan and regional labor marketswill have a direct impact, and/or interact with the educational human capital ofimmigrants, in explaining the occupational attainment of male and female immigrantworkers. Multi-level modeling is used to test the impact of aggregated immigrantreceptivity attitude measures, derived from the General Social Survey, which arespatially merged with immigrant worker human capital, individual-level assimilation,and area labor market indicators to predict managerial/professional and service/laboroccupation attainment of immigrant workers from a merged 1995–97 CurrentPopulation Survey data file. The results provide support for the receptivity attitudesthesis with statistically significant effects on service and labor attainment, but showminimal effects on managerial and professional occupational attainment. The keyreceptivity dimensions affecting occupational attainment are native-born citizens'attitudes concerning the impact of immigrants on American society, and attitudeson English-only language policies. The results show no systematic support for thereverse causation hypothesis that the occupational patterns of immigrants determinethe immigrant receptivity attitudes of citizens.
Detecting Squarrose Knapweed (Centaurea virgata Lam. Ssp. squarrosa Gugl.) Using a Remotely Piloted Vehicle: A Utah Case Study

Determining the location of founding weed populations is critical to minimizing the diffusion of weedy species. Remote sensing is a promising tool for early detection of these small weed patches. The objective of this study was to determine the capability of a small remotely piloted vehicle (RPV) (carrying a digital camera and GPS) to acquire aerial photography from which small infestations of squarrose knapweed (Centaurea virgata Lam. Ssp. squarrosa Gugl.) could be detected and mapped. Two Utah rangeland sites were studied. The location of squarrose knapweed found on the digital air aerial photography (true color) was compared to a complete census of knapweed conducted on the ground. Although the two study sites had different vegetation species mixes, site histories, and soil conditions, the results were comparable. Despite the large scale of the aerial photography, the knapweed detection rate on the spring photography was only 5%. In contrast, knapweed detection rates on late summer imagery were about 5...
Syntactic analysis of seismic waveforms using augmented transition network grammars

Abstract The Augmented Transition Network (ATN) formalism provides a convenient environment for developing syntactic waveform analysis techniques. As an example, an ATN grammar that describes seismic glitch noise waveforms is presented. The grammar produces English descriptions of waveforms and reduces the false alarm rate of an automatic signal detection system. ATN grammars can be extended in several ways to provide error correcting and non-left-right parsing capabilities.
Large-scale early in vitro response to actinobacillus actinomycetemcomitans suggests superantigenic activation of T-cells.

The mode of T-cell response to Actinobacillus actinomycetemcomitans is largely unknown. The present study sought to investigate the hypothesis that A. actinomycetemcomitans expresses superantigens, capable of antigen-non-specific T-cell activation. To that end, peripheral blood mononuclear cells were stimulated with A. actinomycetemcomitans, and T-cell expression of the early activation marker, CD69, was determined by flow cytometry. Results showed that A. actinomycetemcomitans activated a large number of T-cells with magnitude similar to that of staphylococcal enterotoxin superantigens. A. actinomycetemcomitans sonicate preferentially activated T-cells expressing Vβ5.1 and Vβ8, while the extracellular preparation activated Vβ5.1+, Vβ8+, and Vβ12 + T-cells. T-cell response to A. actinomycetemcomitans was observed in the presence of autologous, as well as heterologous, antigen-presenting cells, suggesting a MHC-non-restricted response. Thus, the in vitro response to A. actinomycetemcomitans is characterize...
The injury problem in wrestling

This paper presents an over-all view of the injuries associated with intercollegiate and interscholastic wrestling as conducted in the United States. It classifies injuries according to the mechanism of injury in wrestling and analyzes these mechanisms together with recommendations for treatment and prevention of these conditions.
Yersiniabactin iron uptake: mechanisms and role in Yersinia pestis pathogenesis

Yersiniabactin (Ybt) is a siderophore-dependent iron uptake system encoded on a pathogenicity island that is widespread among pathogenic bacteria including the Yersiniae. While biosynthesis of the siderophore has been elucidated, the secretion mechanism and a few components of the uptake/utilization pathway are unidentified. ybt genes are transcriptionally repressed by Fur but activated by YbtA, likely in combination with the siderophore itself. The Ybt system is essential for the ability of Yersinia pestis to cause bubonic plague and important in pneumonic plague as well. However, the ability to cause fatal septicemic plague is independent of Ybt.
The induction profile of three orally active imidazopyridine-containing cardiotonic agents in rat hepatic microsomes

Abstract The induction of hepatic cytochrome P -450-linked monooxygenases has been studied after the twice daily, oral administration of two imidazo[4,5- c ]pyridine-containing compounds and one imidazo[4,5- b ]pyridine-containing drug. The compounds were administered by the oral route, at different doses, for 6 days after which time hepatic microsomes were prepared. In vitro biochemical assays revealed that all three compounds increased the O -deethylation of 7-ethoxyresorufin in a dose-dependent manner while not significantly affecting either the O -dealkylation of 7-ethoxycoumarin or the levels of NADPH-cytochrome c reductase. Ethylmorphine N-demethylation was decreased after dosing with the imidazo[4,5- b ]pyridine-containing drug. Levels of cytochrome(s) P -450 and liver-to-body weight ratios were not significantly altered. The imidazo[4,5- b ]pyridine-containing compound was more potent in terms of the induction of 7-ethoxyresorufin than either of the imidazo[4,5- c ]pyridine-containing compounds but was approximately fourfold less active in this regard than 3-methylcholanthrene. No induction of cytochrome- P -450-linked monooxygenase activities was evident at a twice daily dose of 5 mg/kg for 6 days for all three compounds tested, constituting a no-effect level. The imidazo[4,5- c ]pyridine-containing compounds exhibited modified Type II difference spectra when added to a suspension of rat hepatic microsomes. The imidazo[4,5- b ]pyridine-containing compound has previously been reported to be (i) a rapid and potent inducer of monooxygenase activity and (ii) have a Type II difference spectrum.
Trends in Asthma Prevalence: the Bogalusa Heart Study

Background Epidemiologic surveys from different parts of the developed world are showing increases in asthma prevalence; the causes are not known. Objective To describe trends in prevalence of childhood asthma measured across serial cross-sectional surreys of the school age population of Bogalusa, Louisiana. Methods The Bogalusa Heart Study is a long-term epidemiologic study of risk factors for cardiovascular disease in children in a stable, semirural, biracial community. Part of the examination includes a parent-completed health history questionnaire. The item, “Does your child have or has your child had in the past… asthma?” was included in the 1983–5, 1987–8, and 1992–4 surveys. Data analysis was restricted to subjects aged 5 to 17 years. Results Three thousand two hundred seventy-six subjects participated in 1983–5, 3,256 in 1987–8, and 3,128 in 1992–4. Reported asthma prevalence increased from 9.2% to15.9% between1983–5 and 1992–4. Maternal smoking was associated with asthma in all three surveys. Young age and African American ethnicity were associated with asthma only in the 1992–4 survey. Conclusions The prevalence of asthma among the school age population of Bogalusa, Louisiana increased by 73% between the 1983–5 and the 1992–4 surveys. Whether the increase in asthma prevalence represents an increase in disease presence or an increase in disease recognition cannot be determined from these data.
The scientific status of fusion

Abstract The development of fusion energy has been a large-scale scientific undertaking of broad interest. The magnetic plasma containment in tokamaks and the laser-drive ignition of microfusion capsules appear to be scientifically feasible sources of energy. These concepts are bounded by questions of required intensity in magnetic field and plasma currents or in drive energy and, for both concepts, by issues of plasma stability and energy transport. The basic concept and the current scientific issues are described for magnetic fusion and for the interesting, but likely infeasible, muon-catalyzed fusion concept. Inertial fusion is mentioned, qualitatively, to complete the context. Fusion appears to release energy in rather large quantities (about 1000 MW) and significant new devices are needed to make progress. For magnetic fusion, the required net energy production within the plasma may be accomplished soon, but the more useful goal of self-sustained plasma ignition requires a new device of somewhat uncertain (factor of 2) cost and size.
Clean technology R&D and innovation in emerging countries—Experience from China

Abstract This paper touches upon two key issues related to clean technology deployment in emerging countries: what is the life cycle of R&D and innovation? And where does the R&D funding come from? The paper holds that the innovation climate, system and process in emerging countries do not follow the same trajectory as those in developed countries. Crafting an innovation model that is adapted to the needs and conditions of emerging countries thus is critical. Through revealing the four phases of an innovation life cycle in emerging countries, the paper highlights the dominant role of the public sector in clean technology R&D. With regards to R&D funding, the paper concludes that emerging countries could craft their domestic policy to spur clean technology R&D and innovation. China's experience demonstrates an array of policy measures that could reach this goal. These include designing a national science and technology strategy with a focus on clean energy, establishing funding programs to support clean energy R&D, assembling and managing multidisciplinary teams to bring together different types of expertise, and creating favorable policy environment to incentivize the private sector's investment in clean technology.
A site-directed mutagenesis analysis of tNOX functional domains

Constitutive NADH oxidase proteins of the mammalian cell surface exhibit two different activities, oxidation of hydroquinones (or NADH) and protein disulfide-thiol interchange which alternate to yield oscillatory patterns with period lengths of 24 min. A drug-responsive tNOX (tumor-associated NADH oxidase) has a period length of about 22 min. The tNOX cDNA has been cloned and expressed. These two proteins are representative of cycling oxidase proteins of the plant and animal cell surface. In this report, we describe a series of eight amino acid replacements in tNOX which, when expressed in Escherichia coli, were analyzed for enzymatic activity, drug response and period length. Replacement sites selected include six cysteines that lie within the processed plasma membrane (34 kDa) form of the protein, and amino acids located in putative drug and adenine nucleotide (NADH) binding domains. The latter, plus two of the cysteine replacements, resulted in a loss of enzymatic activity. The recombinant tNOX with the modified drug binding site retained activity but the activity was no longer drug-responsive. The four remaining cysteine replacements were of interest in that both activity and drug response were retained but the period length for both NADH oxidation and protein disulfide-thiol interchange was increased from 22 min to 36 or 42 min. The findings confirm the correctness of the drug and adenine nucleotide binding motifs within the tNOX protein and imply a potential critical role of cysteine residues in determining the period length.
Pancreatic cancers depend on a non-canonical glutamine metabolism pathway

Cancer cells exhibit metabolic dependencies that distinguish them from their normal counterparts. Among these addictions is an increased utilization of the amino acid glutamine (Gln) to fuel anabolic processes. Recently, we reported the identification of a non-canonical pathway of Gln utilization in human pancreatic cancer cells that is required for tumor growth. While most cells utilize glutamate dehydrogenase (GLUD1) to convert Gln-derived glutamate (Glu) into a-ketoglutarate (aKG) in the mitochondria to fuel the tricarboxylic acid cycle, pancreatic cancer cells rely on a distinct pathway that integrates the mitochondrial and cytosolic aspartate aminotransferases GOT2 and GOT1. By generating aKG from Glu (in conjunction with the conversion of oxaloacetate into aspartate), GOT2 fuels anaplerosis in place of GLUD1. The Asp created is released into the cytosol and acted on by GOT1. This is subsequently used through as eries of reactions to yield cytosolic NADPH from malic enzyme. Importantly, we have demonstrated that pancreatic cancers are strongly dependent on this series of reactions to maintain redox homeostasis which enables proliferation. Herein, we detail the subcellular compartmentalization and consequences of the aforementioned reactions on pancreatic cancer metabolism. We have also investigated the essentiality of this pathway in other contexts and find that pancreatic cancers have a uniform and unique reliance on this pathway, which may provide novel therapeutic approaches to treat these refractory tumors.
Evaluating the efficacy of the National Cholesterol Education Program adult treatment guidelines: cholesterol lowering intervention program.

Abstract Background . A cross-sectional analysis was conducted to test the feasibility of the National Cholesterol Education Program Adult Treatment Panel I Guidelines (ATPI) in physician office practices. Methods . Twenty-two physician practices in communities from western Pennsylvania and West Virginia were recruited. Using a patient tracking system, 9,171 patients were assessed for cholesterol screening and treatment by their physicians according to the ATPI guidelines. Results . Cholesterol screening was ordered for 1,698 patients or 19% of the population visiting the physician offices. The reasons for not screening included the patient was already under therapy (2,371), screened within the past 5 years (1,714), or acutely ill at the time of the visit (1,691). The frequency of patient refusal for screening was low (444), However, the majority of patient diagnoses were based on a single lipid measurement, and only 817 or 56% of patients evaluated had lipoprotein measures obtained prior to treatment. Follow-up measurement was not performed according to the ATPI schedule, and the magnitude of cholesterol response was inversely related to time to first follow-up measurement. Conclusions . Many patients in these physician practices had initial cholesterol screening. However, repeat measurements as recommended for initial evaluation were not performed routinely, nor were most patients followed within the recommended S-month time period, This lack of follow-up is detrimental to effective, long-term patient management since the magnitude of the cholesterol response is related to time of the first follow-up measurement.
Observation of trapped light within the radiation continuum

United States. Army Research Office (Institute for Soldier Nanotechnologies under contract no. W911NF-07-D0004)
Comparison of three methods to reduce energy density. Effects on daily energy intake.

Reductions in food energy density can decrease energy intake, but it is not known if the effects depend on the way that energy density is reduced. We investigated whether three methods of reducing energy density (decreasing fat, increasing fruit and vegetables, and adding water) differed in their effects on energy intake across the day. In a crossover design, 59 adults ate breakfast, lunch, and dinner in the laboratory once a week for 4 weeks. Across conditions, the entrees were either standard in energy density or were reduced in energy density by 20% using one of the three methods. Each meal included a manipulated entree along with unmanipulated side dishes, and all foods were consumed ad libitum. Reducing the energy density of entrees significantly decreased daily energy intake compared to standard entrees (mean intake 2667 ± 77 kcal/day; 11,166 ± 322 kJ/day). The mean decrease was 396 ± 44 kcal/day (1658 ± 184 kJ/day) when fat was reduced, 308 ± 41 kcal/day (1290 ± 172 kJ/day) when fruit and vegetables were increased, and 230 ± 35 kcal/day (963 ± 147 kJ/day) when water was added. Daily energy intake was lower when fat was decreased compared to the other methods. These findings indicate that a variety of diet compositions can be recommended to reduce overall dietary energy density in order to moderate energy intake.
Target inference from collections of genomic intervals

Finding regions of the genome that are significantly recurrent in noisy data are a common but difficult problem in present day computational biology. Cores of recurrent events (CORE) is a computational approach to solving this problem that is based on a formalized notion by which "core" intervals explain the observed data, where the number of cores is the "depth" of the explanation. Given that formalization, we implement CORE as a combinatorial optimization procedure with depth chosen from considerations of statistical significance. An important feature of CORE is its ability to explain data with cores of widely varying lengths. We examine the performance of this system with synthetic data, and then provide two demonstrations of its utility with actual data. Applying CORE to a collection of DNA copy number profiles from single cells of a given tumor, we determine tumor population phylogeny and find the features that separate subpopulations. Applying CORE to comparative genomic hybridization data from a large set of tumor samples, we define regions of recurrent copy number aberration in breast cancer.
Affinity purification of angiotensin type 2 receptors from N1E-115 cells : evidence for agonist-induced formation of multimeric complexes

: The murine neuroblastoma N1E-115 cell line possesses type 1 and type 2 angiotensin II (Angll) receptor subtypes. In vitro differentiation of these cells substantially increases the density of the AT2-receptor subtype, whereas the density of the AT1 receptors remains unchanged. In the present study, we report that the zwitterionic detergent 3-[(3-cholamidopropyl)dimethylammonio]- 1-propanesulfonate (CHAPS) selectively solubilized AT2receptors from N1E-115 cell membranes and that these receptors could be purified further to near homogeneity by affinity chromatography. More specifically, the presence of an agonist (Angll) during affinity purification of AT2 receptors resulted in the elution of high (110-kDa) and low (66-kDa) molecular mass proteins as determined by gel electrophoresis under nonreducing conditions. In contrast, when the nonselective antagonist Sar1, lle8-Angll was used during purification, only the lower 66-kDa protein was observed. Affinity purification in the presence of the peptide and nonpeptide AT2-receptor antagonists CGP42112A and PD123319 also resulted in elution of the same 66-kDa protein, but unlike that in the presence of Sar1, lle8-Angll, some of the high molecular weight site was observed as well. On the other hand, Losartan, an AT1-receptor antagonist, was completely ineffective in eluting any Angll receptors from the affinity column, further confirming their AT2 identity. After agonist elution, the 110-kDa band dissociated into two low molecular mass bands of 66 kDa and 54 kDa when sodium dodecyl sulfate-gel electrophoresis was run under reducing conditions. The 110-kDa and 66-kDa proteins, but not smaller, affinity-purified proteins, specifically bound 125l-Angll as determined by covalent cross-linking of 125l-Angll to the receptors with the homobifunctional cross-linker disuccinimidyl suberate, or by size exclusion chromatography on a TSK 3000 SW column. Lastly, immunoblot analysis of affinity- purified material with antibodies selective for AT2 receptors revealed major immunoreactive proteins of 110 kDa and 66 kDa in the presence of an agonist, whereas the same 66-kDa protein, as well as a smaller (54-kDa) immunoreactive protein, was detected under reducing conditions. Collectively, these data suggest that CHAPS-solubilized AT2 receptors from N1E-115 cells may consist of a binding protein of approximately 66 kDa, which in the presence of an agonist readily associates with other smaller proteins to form larger multimeric complexes.
Cross-talk between G Protein-coupled and Epidermal Growth Factor Receptors Regulates Gonadotropin-mediated Steroidogenesis in Leydig Cells

Gonadal steroid production is stimulated by gonadotropin binding to G protein-coupled receptors (GPCRs). Although GPCR-mediated increases in intracellular cAMP are known regulators of steroidogenesis, the roles of other signaling pathways in mediating steroid production are not well characterized. Recent studies suggest that luteinizing hormone (LH) receptor activation leads to trans-activation of epidermal growth factor (EGF) receptors in the testes and ovary. This pathway is critical for LH-induced steroid production in ovarian follicles, probably through matrix metalloproteinase (MMP)-mediated release of EGF receptor (EGFR) binding ectodomains. Here we examined LH and EGF receptor cross-talk in testicular steroidogenesis using mouse MLTC-1 Leydig cells. We demonstrated that, similar to the ovary, trans-activation of the EGF receptor was critical for gonadotropin-induced steroid production in Leydig cells. LH-induced increases in cAMP and cAMP-dependent protein kinase (PKA) activity mediated trans-activation of the EGF receptor and subsequent mitogen-activated protein kinase (MAPK) activation, ultimately leading to StAR phosphorylation and mitochondrial translocation. Steroidogenesis in Leydig cells was unaffected by MMP inhibitors, suggesting that cAMP and PKA trans-activated EGF receptors in an intracellular fashion. Interestingly, although cAMP was always needed for steroidogenesis, the EGFR/MAPK pathway was activated and necessary only for early (30-60 min), but not late (120 min or more), LH-induced steroidogenesis in vitro. In contrast, 36-h EGF receptor inhibition in vivo significantly reduced serum testosterone levels in male mice, demonstrating the physiologic importance of this cross-talk. These results suggest that GPCR-EGF receptor cross-talk is a conserved regulator of gonadotropin-induced steroidogenesis in the gonads, although the mechanisms of EGF receptor trans-activation may vary.
Chemical Composition of Earth, Venus, and Mercury

Model compositions of Earth, Venus, and Mercury are calculated from the premise that planets and chondrites underwent four identical fractionation processes in the solar nebula. Because elements of similar properties stay together in these processes, five constraints suffice to define the composition of a planet: mass of the core, abundance of U, and the ratios K/U, Tl/U, and FeO/(FeO + MgO). Complete abundance tables, and normative mineralogies, are given for all three planets. Review of available data shows only a few gross trends for the inner planets: FeO decreases with heliocentric distance, whereas volatiles are depleted and refractories are enriched in the smaller planets.
Two-element phased array of antiguided vertical-cavity lasers

We demonstrate antiguided coupling of two adjacent vertical-cavity surface-emitting lasers (VCSELs), obtaining a 1×2 phase-locked array at 869 nm. The lateral index modification required for antiguiding is achieved by a patterned 3 nm etch performed between two epitaxial growths. In contrast with prior coupled VCSELs, adjacent antiguided VCSELs can emit in phase and produce a single on-axis lobe in the far field. Greater than 2 mW of in-phase output power is demonstrated with two VCSELs separated by 8 μm. Moreover, phase locking of two VCSELs separated by 20 μm is observed, indicating the possibility of a promising class of optical circuits based upon VCSELs that interact horizontally and emit vertically.
Spatial evolution of the computer industry in the USA

Abstract This paper examines the spatial evolution of computers across 317 metro areas in the USA since the introduction of the personal computer. We start by examining the relative distribution of employment across cities, examining how that distribution changes in 1977–1992 and how cities move through the distribution. For computers, transition matrices are stationary, with the industry exhibiting no tendency to settle down, nor any tendency of retrenchment during periods of national high-tech employment decline. There is no tendency of the relative size distribution of computer employment to collapse, go bimodal, etc. Overall computers exhibit some turbulence, with dramatic big winners and losers among cities, as well as persistence for some cities in employment shares. In attracting or repelling an industry, urban heterogeneity is important. Large, well educated cities near San Jose have a much greater chance of attracting high-tech employment (much lower mean first passage times moving up states) and less chance of losing it. In assessing the determinants of persistence in local employment patterns we examine sources of productivity growth. We find strong evidence of significant dynamic own industry externalities for single plant firms and little evidence of urbanization-Jacobs-knowledge type externalities. Corporate plants in computers seem to be self-reliant and not really influenced by externalities.
Modeling epidemiologic studies of occupational cohorts for the quantitative assessment of carcinogenic hazards

Epidemiologic studies of occupational cohorts have played a major role in the quantitative assessment of risks associated with several carcinogenic hazards and are likely to play an increasingly important role in this area. Relatively little attention has been given in either the epidemiologic or the risk assessment literature to the development of appropriate methods for modeling epidemiologic data for quantitative risk assessment (QRA). The purpose of this paper is to review currently available methods for modeling epidemiologic data for risk assessment. The focus of this paper is on methods for use with retrospective cohort mortality studies of occupational groups for estimating cancer risk, since these are the data most commonly used when epidemiologic information is used for QRA. Both empirical (e.g., Poisson regression and Cox proportionate hazards model) and biologic (e.g., two-stage models) models are considered. Analyses of a study of lung cancer among workers exposed to cadmium are used to illustrate these modeling methods. Based on this example it is demonstrated that the selection of a particular model may have a large influence on the resulting estimates of risk.
Constructional changes made to the Minnesota MP tandem Van de Graaff accelerator

Abstract Since initial operation of the Minnesota MP tandem Van de Graaff accelerator began in 1966 a number of changes have been made to prevent recurring faults and to improve machine performance. A description of these modifications to the mechanical and electrical structure of the machine and the resulting improvements in performance are summarized. A preliminary report on the operation of accelerator tubes of a modified design is included.
New Direction and Discovery on the Hunger Front: Toward a Sociology of Food Security/Insecurity:

In this paper I examine themes for sociological inquiry on food security/insecurity and the expanded role of sociology in a new discovery of this issue that connects research, teaching, and action. I establish the sociological significance of food security/insecurity through a number of interconnected, specialized thematic clusters including population, environment, and ecology; technology, development, and infrastructure; politics and the global political economy; stratification, poverty, and inequality; and conflict, war, and militarization. It is within these clusters that sociology can strongly influence new directions in research on food security/insecurity while concurrently exploring the issue in the classroom and community. Humanist sociology and social justice perspectives taking a critical perspective on food security/insecurity extend logically to teaching and action. In this regard, the discipline can move toward what a sociology of food security/insecurity should be, including a greater role ...
Simple modification of a commercial mass spectrometer for metastable data collection

Abstract The geometry of a Hitachi Perkin—Elmer RMU-7 double-focusing mass spectrometer was reversed by interchanging the positions of ion source and electron multiplier. The high metastable resolution of the modified instrument (150 for narrow peaks) resulted in 57 new transitions found for n-decane. Because of the mode of operation, reproducible peak shapes and intensities can be obtained.
Unusual effects of oscillating flows in an annulus on mass transfer and separation

Abstract Oscillating flows is a novel separation method to aid in air revitalization in self-supporting environments that are important to NASA's advanced life support. This purely mechanical process can assist in the removal of carbon dioxide, fine particles, and other contaminants from the air. Separation can be achieved as oscillating flows markedly increase the mass transfer of a dilute species in a gas over that due to pure molecular diffusion. If two gaseous species are present in a carrier, the interaction between the time constants associated with the different diffusion coefficients, kinematic viscosity of the carrier, and the frequency of oscillation dictate the rate of mass transfer and amount of separation. The geometry of the system is also an important factor in the mass transfer and separation. Specifically, models have been developed to determine the mass transfer and separation in the annular space between two concentric cylinders. If the inner cylinder is slightly off center from the outer cylinder, the mass transfer decreases but the separation increases in relation to the oscillatory concentric case. The decrease in mass transfer is contrary to the result that would be expected in steady flows given by Taylor dispersion. A detailed explanation of the physics of oscillating flows and the unusual effects exhibited by different geometries will be presented.
Social system of round-tailed ground squirrels

Abstract The social system of round-tailed ground squirrels, Spermophilus tereticaudus , is quantitatively described in terms of seasonal changes in interaction rates, the effect of age and sex on type and frequency of interaction, the differential response to kin and non-kin, the determinants of dominance, including territoriality, the associations between classes of individuals, and the dispersion of home ranges and core areas. From January to March, the adult squirrels were sociable and nonterritorial. Following copulation in March, they were unsociable and territorial. In May and June, juveniles lived mainly within their mothers' territories. Those juveniles that did not disperse from the study area in late June established territories near their mothers. From September to December, all squirrels were inactive underground.
Managers in the People's Republic of China

Executive Overview Since many U.S. executives currently or one day will work with Chinese managers, it seems worthwhile to examine management in the P.R.C. This article—based upon interviews with 50 Chinese workers and 120 managers—examines the forces that press upon Chinese managers and subsequently looks at their management approaches. We find that Deng Xiaoping's “reform” program and inflation have the strongest impact upon managers. These, along with the Communist Party, 40 years of socialism, feudalistic values, guanxi (influence peddling), and the labor-intensive economy mold the management seen today. These forces tend to squeeze managers into “low-power” positions, from which they operate quite pragmatically. Specially, China's managers develop warm relationships with workers, offer favors, and loosen the operating rules. In addition, they shame workers, request assistance from the workers' families, and some attempt to reward productive workers. Finally, they rely upon their guanxi. Like it or lo...
An Economic Analysis of Licensure and Public Policy: Evidence from the Social Work Case

Occupational licensure is commonly accepted as a means of protecting consumers by ensuring minimum levels of professional competence. This study analyzes the rationale for licensure in terms of consumer information and consumer choice, applying the analysis to the proposal to license social workers in Tennessee. The analysis makes it possible to separate the numerous issues involved in the licensure question, identifying the probable impact of the proposed measures in terms of a clearer identification of consumers' interests. It is shown that the need for licensure is tied to the manner in which services are provided. In the social work case this means that while the positions of social workers would be enhanced, licensure would offer their client-consumers little protection which they do not already enjoy.
Diverse stability and catalytic properties of human tryptase alpha and beta isoforms are mediated by residue differences at the S1 pocket.

Recombinant human tryptases (rHTs) corresponding to R and ‚ isoforms were characterized. rHT‚ was similar to tryptase isolated from skin (HST); it was a tetramer, hydrolyzed model substrates efficiently, and was functionally unstable when incubated under physiological conditions. Activity was lost rapidly (t1/2 1 min) by a reversible process similar to that observed for the spontaneous inactivation of HST. Circular dichroism (CD) and intrinsic fluorescence emission (IFE) spectra of active rH˘‚ corresponded to those of active HST and upon spontaneous inactivation IFE decreased in parallel to activity loss. rHTR differed from HST in catalytic ability and stability. rHT R did not react with model substrates, an active site titrant, or a competitive inhibitor of HST/rHT ‚. IFE and CD spectra were similar to those of the active and not the spontaneously inactivated form of HST. Under physiological conditions, rHTR IFE decreased at a rate 900-fold slower than that observed for HST, and rHTR remained tetrameric when examined by size exclusion chromatography at physiological salt concentration. Thus, rHTR is a stable "inactive" form of HT. Three active site variants of rHT R, K192Q, D216G, and K192Q-D216G were characterized. Residues 192 and 216 (chymotrypsinogen numbers for residues 191 and 215 of rHTR) lie at the entrance to the primary specificity (S1) pocket, and the mutations converted them to the residues of HT‚. While K192Q displayed the same properties as rHTR, the catalytic and stability characteristics of D216G and K192Q-D216G progressively approached those of HST. Thus, the contrasting stability/ activity properties of rHTR and rHT‚ are largely related to differences at the S1 pocket. On the basis of the properties of the variants, we suggest that the side chain of Asp216 is blocking and stabilizing the S1 pocket and that this stabilization is sufficient to prevent spontaneous inactivation.
Chikungunya on the move

In December 2013, chikungunya virus (CHIKV) transmission was reported for the first time in the Americas. Since then it has spread quickly, with more than 1 million suspected and confirmed cases being reported in one year, where previously there were only sporadic travel-related cases. Transmission patterns suggest that the epidemic in the southern hemisphere is only beginning and that chikungunya will not go away anytime soon.
Dominant occipital (alpha) rhythm frequency in early stage Alzheimer's disease and depression

The sinusoidal 8-13 Hz wave form that dominates in the occipital EEG record during relaxed wakefulness is known as alpha rhythm or dominant occipital rhythm. The frequency of this rhythm is known to decrease with normal aging with organic brain diseases. Here we report dominant occipital frequency (DOF) data for 41 early stage AD patients, 50 age-, sex- and health-matched control subjects and 22 subjects with major depressive disorder. DOF was assessed blindly for each subject from 10 or more samples during relaxed wakefulness in an all-night polysomnogram. Mean DOF was significantly lower in the AD (mean +/- S.D. was 8.24 +/- 1.04) than control group (9.48 +/- 0.57; F = 56, P less than 0.001). Mean DOF was also significantly lower in the depressed than control group (9.20 +/- 0.50 vs. 9.48, F = 5.0, P less than 0.05). In discriminant analyses, DOF achieved an overall correct classification rate of 77% for AD vs. control subjects, and 72% for AD vs. depressed subjects. These results indicate that DOF may be useful in identifying early stages of AD in healthy, drug-free populations.
Goldstone realization of Lorentz-symmetry and supersymmetry at finite temperature

Abstract The Ward-Takahashi identities of Lorentz symmetry are examined at finite temperature. It is shown that the Lorentz symmetry is broken with the Goldstone realization. The analogy with finite-temperature supersymmetry-breaking in an R -invariant model is explained.
Equilibrium geometries and associated energetic properties of mixed metal-silicon clusters from global optimization.

The structural properties of the cluster series Me(m)Si(7-m) (Me = Cu and Li, m < or = 6) are studied by density functional theory (DFT) employing a plane wave basis. The equilibrium geometries and energetic properties of these clusters are obtained by use of the simulated annealing procedure in conjunction with the Nose thermostat algorithm. The lowest energy isomer thus obtained is analyzed by density functional theory at the B3LYP/6-311+G(d,p) level including all electrons. Pentagonal ground state structures derived from the D(5)(h) equilibrium geometries of both Si(7) and Cu(7) are obtained for Cu(m)Si(7-m) with m < 6. The Li(m)Si(7-m) clusters, in contrast, tend toward adsorption geometries where m Li atoms are attached to a Si(7-m)framework with pronounced negative charge. For both Li(m)Si(7-m) and Cu(m)Si(7-m), a marked decrease of the energy gap is found as the number of metal atom constituents increases.
On the derivatives of X-ray functions

We show that for every $ n \geqq 4, 0 \leqq k \leqq n - 3, p \in (0, 3] $ and every origin-symmetric convex body K in $ \mathbb{R}^n $ , the function $ \parallel x \parallel^{-k}_{2} \parallel x \parallel^{-n+k+p}_{K} $ represents a positive definite distribution on $ \mathbb{R}^n $ , where $ \parallel \cdot \parallel_{2} $ is the Euclidean norm and $ \parallel \cdot \parallel_{K} $ is the Minkowski functional of K. We apply this fact to prove a result of Busemann-Petty type that the inequalities for the derivatives of order (n - 4) at zero of X-ray functions of two convex bodies imply the inequalities for the volume of average m-dimensional sections of these bodies for all $ 3 \leqq m \leqq n $ . We also prove a sharp lower estimate for the maximal derivative of X-ray functions of the order (n - 4) at zero.
Weak decays ΞQ→ΛQπ

Abstract The weak decays Ξ b →Λ b π and Ξ c →Λ c π , in which the heavy quark is not destroyed, are discussed. The branching fractions for these decays, corresponding to an absolute rate of order 0.01 ps −1 , should be at a one percent level for the b hyperons and at a (few) per mill level for Ξc, possibly making feasible their experimental study in future. It is shown, through an application of the heavy quark limit, the flavor SU(3) symmetry, and PCAC, that the ΔI=1/2 rule should hold very well in these decays, and also that the Ξb decays are purely S wave in the symmetry limit, while the difference between the S wave amplitudes of the Ξc decays and those for the Ξb is related, in terms of the heavy quark expansion, to the difference of the total decay rates within the ( Ξ c , Λ c ) triplet of charmed hyperons. We also comment on the amplitudes of the semileptonic transitions Ξ Q →Λ Q l ν and on the weak radiative decays Ξ Q →Λ Q γ .
Electronic states of prototype supertetrahedral framework materials

The electronic structure of a class of porous crystalline materials built of supertetrahedra is studied using ab initio density-functional theory. We examine the sulfide supertetrahedral $\mathrm{I}4\ifmmode\bar\else\textasciimacron\fi{}2\mathrm{d}$ cristobalitelike structure composed of supertetrahedra joined by corner-sharing sulfur atoms. Two examples are given. A charge neutral system, ${\mathrm{In}}_{4}{\mathrm{Sn}}_{6}{\mathrm{S}}_{18},$ and a charged system ${\mathrm{In}}_{10}{\mathrm{S}}_{18}^{6\ensuremath{-}}$ (ASU-34) are studied. The large supertetrahedral building blocks produce cavernous interstitial pores. We find that the ${\mathrm{In}}_{10}{\mathrm{S}}_{18}^{6\ensuremath{-}}$ pores contain particle-in-a-box ``deep-level'' electron states near the band gap; this makes these materials interesting antidot semiconductors. The energy of the deep-level state is sensitive to the intersupertetrahedral bond angle, and for large angles the level moves into the valence band producing a semiconductor-to-metal transition.
Phosphorylation of HMG-I by Protein Kinase C Attenuates Its Binding Affinity to the Promoter Regions of Protein Kinase C γ and Neurogranin/RC3 Genes

A 20-kDa DNA-binding protein that binds the AT-rich sequences within the promoters of the brain-specific protein kinase C (PKC) gamma and neurogranin/RC3 genes has been characterized as chromosomal nonhistone high-mobility-group protein (HMG)-I. This protein is a substrate of PKC alpha, beta, gamma, and delta but is poorly phosphorylated by PKC epsilon and zeta. Two major (Ser44 and Ser64) and four minor phosphorylation sites have been identified. The extents of phosphorylation of Ser44 and Ser64 were 1:1, whereas those of the four minor sites all together were 100-fold reduction in binding affinity. The two cdc2 kinase phosphorylation sites of HMG-I are adjacent to the N terminus of two of the three predicted DNA-binding domains. In comparison, one of the major PKC phosphorylation sites, Ser64, is adjacent to the C terminus of the second DNA-binding domain, whereas Ser44 is located within the spanning region between the first and second DNA-binding domains. The current results suggest that phosphorylation of the mammalian HMG-I by PKC alone or in combination with cdc2 kinase provides an effective mechanism for the regulation of HMG-I function.
Transcriptional control at regulatory checkpoints by histone deacetylases: molecular connections between cancer and chromatin

Cancer cells exhibit a set of unique properties that distinguish them from their normal counterparts. Among these features are increased growth rates, loss of differentiation, escape from cell death pathways, evasion of anti-proliferative signals, a decreased reliance on exogenous growth factors and escape from replicative senescence. Acquisition of these features by malignant cells requires impairment of normal cellular control mechanisms. Over the past few years, it has become increasingly apparent that an important subset of the molecular changes commonly found in cancer cells involves inappropriate regulation of gene expression. This review will address regulatory pathways whose disruption contributes to the malignant phenotype. The failure to deacetylate and thus repress transcription by the Class I histone deacetylases HDAC1 and HDAC2 due to disruption of the Rb family of proteins has been firmly established as a mechanism leading to increases in growth rate and cellular proliferation. Recent data suggest that this regulatory circuit also executes G(1) checkpoint arrest downstream of DNA damage, cellular senescence and contact inhibition. In contrast to this failure to deacetylate, it now seems probable that changes in differentiation status may result in part from inappropriate deacetylation and concomitant transcriptional repression mediated by the Class II histone deacetylases. This inappropriate deacetylation by HDAC4, HDAC5 and HDAC6 follows their relocalization from the cytoplasm to the nucleus. Thus, multiple classical features of cancer cells can be manifested by improper histone deacetylation.
Cyclic AMP‐dependent protein kinase‐induced vimentin filament disassembly involves modification of the N‐terminal domain of intermediate filament subunits

Abstract The intermediate filament protein vimentin was phosphorylated with cAMP-dependent protein kinase under conditions that induce filament disassembly. Digestion of phosphorylated vimentin with lysine-specific endoprotease and subsequent tryptic peptide mapping indicated that a 12 kDa N-terminal fragment contained all the phosphorylation sites found in the intact molecule. Analysis of cyanogen bromide digests indicated that two phosphorylated peptides were produced, with the major 32 P-labeled species representing amino acid position 14–72, and a minor 32 P-labeled peptide representing amino acid positions 1–13. These results demonstrate that phosphorylation of sites within the N-terminal head domain of vimentin are associated with phosphorylation induced filament disassembly.
On Maximum Principles for -Metaharmonic Equations

We study homogeneous linear elliptic partial differential equations of even order. Several maximum principle results are deduced for such equations as well as a priori bounds for certain boundary value problems.
Particulate forms of phenylalanyl-tRNA synthetase from Ehrlich ascites cells

Abstract Over 80% of the phenylalanyl-tRNA synthetase activity in Ehrlich ascites cell homogenates was found to be associated with the high speed particulate fraction. This enzyme activity occurred in two principle forms: activity bound to the ribosomes, and activity as part of a complex sedimenting at approximately 25S in a sucrose density gradient. The ribosome-associated enzyme was shown to be bound to the 60S ribosomal subunit. Exposure of the ribosomes to RNA resulted in removal of synthetase activity from the ribosomes and the concomitant appearance of activity in a complex sedimenting at 25S.