cssi/SciSciGPT-SciSciNet huggingface dataset:
Flavo-diiron enzymes: Nitric oxide or dioxygen reductases?

Flavo-diiron enzymes are among the most recently recognized sub-class of non-heme diiron proteins. The active sites of flavo-diiron enzymes consist of a unique juxtaposition of a flavincofactor and a histidine, glutamate, aspartate-ligated, solvent-bridged diiron site. Flavo-diiron enzymes were initially thought to function as scavenging dioxygen reductases (s-O2Rs), based on their ability to catalyze the reduction of dioxygen to water, thus protecting air-sensitive bacteria and archaea against “oxidative stress”. However, genetic and biochemical evidence strongly suggests that, at least in some bacteria, flavo-diiron enzymes function as scavenging nitric oxide reductases (s-NORs), catalyzing the reduction of nitric oxide to nitrous oxide, thus, protecting against “nitrosative stress” under anaerobic growth conditions. Key unsettled questions include: should flavo-diiron enzymes be divided into s-NOR and s-O2R categories, and, if so, what features of the active sites distinguish the two activities? If not, how does the active site accommodate and optimize the relative levels of these activities? Systematic investigations of the structures and catalytic mechanisms of several flavo-diiron enzymes constitute an approach to answer these questions. The current state of knowledge and progress toward this end is reviewed here.
A method for size separation of murine spleen cells using counterflow centrifugation.

A method for the rapid separation of murine spleen cells into subpopulations on the basis of their size has been developed using counterflow centrifugation. Upon separation of normal spleen cells with a mean cell volume of 125.5 ± 6.0, 5 fractions of cells were obtained with mean cell volumes which ranged from 107.8 ± 3.2 μm3 in fraction 1 to 152.7 ± 4.9 μm3 in fraction 5. The cells in these 5 fractions were characterized by analysis on a fluorescence activated cell sorter (FACS) after staining with fluorescein conjugated anti-μ, δ, Ia, or Thy 1.2 antibodies, and by assaying for the presence of non-specific esterase activity. Surface Ig+, Ia+ B lymphocytes and Thy 1.2 T lymphocytes were present in all 5 fractions. However, while these T and B lymphocytes accounted for virtually all of the cells in the first 3 fractions, non-T, non-B cells were found in fractions 4 and 5, and represented 30% of the total population in the 5th fraction. Comparison of the intensity of anti-μ, δ or Ia staining of the B cells in fractions 1–5 revealed differences which suggested that B cell size correlated with different activation states of these cells. Increases in the intensity of the staining of T lymphocytes by anti-theta antibodies were also noted in the various fractions. The capacity of the B and T cells in each fraction to proliferate to B or T cell mitogens, respectively, was proportional to their frequency within the fractions. By contrast, the fractions containing larger cells were enriched in cells which proliferated in vitro in the absence of added mitogen. Furthermore, only fractions containing larger cells had the capacity to stimulate allogeneic T cell proliferation in a mixed lymphocyte reaction. Our data suggest that this technique provides a useful method for separating splenocytes on the basis of cell size. Use of this methodology provides a way to correlate cell size with phenotypic surface markers and functional abilities.
Localization of CD44 at the Invasive Margin of Glioblastomas by Immunoelectron Microscopy

Glioblastoma multiforme is a highly invasive primary brain tumor, which is known to strongly express the CD44 cell adhesion receptor. A number of experimental studies suggest that the interaction of this receptor with extracellular matrix (ECM) proteins such as hyaluronic acid may in part mediate human glioma cell adhesion and invasion of brain tissue. Although the expression of CD44 and its spliced variants in brain tumors have been extensively studied, there have been no reports localizing its expression to the invasive margin of the tumor. The authors used immunoelectron microscopy to investigate the expression patterns of CD44 in an in vitro organotypic invasion assay. Tumor spheroids initiated from the U373 MG human glioblastoma line were confronted with fetal rat brain aggregates in a spheroid coculture system. The CD44 expression appeared at the interface between glioblastoma tumor spheroids and brain tissue, as well as in the spheroid itself. CD44 immunoreactivity was not detectable in mature 21-d...
Two (E,E)- and (Z,E)-thiazol-5-ylpenta-2,4-dienones.

In order to characterize the structural elements that might play a role in non-covalent DNA binding by the antitumor antibiotic leinamycin, we have solved the crystal structures of the two leinamycin analogs, methyl (R)-5-{2-[1-(tert-butoxy­carbonyl­amino)­ethyl]­thia­zol-4-yl}penta-(E,E)-2,4-dienoate, C16H22N2O4S, (II), and 2-methyl-8-oxa-16-thia-3,17-di­aza­bicyclo­[12.2.1]­heptadeca-(Z,E)-1(17),10,12,14-tetraene-4,9-di­one, C14H16N2O3S, (III). The penta-2,4-dienone moiety in both of these analogs adopts a conformation close to planarity, with the thia­zole ring twisted out of the plane by 12.9 (2)° in (II) and by 21.4 (4)° in (III).
Recent Advances in the Role of Immunity in Atherosclerosis

The immune system serves to protect the host from a diverse array of pathogens that evolve rapidly in an effort to breach immune security checkpoints. These defense mechanisms operate continuously to keep exogenous pathogens from propagating their own species, although this heightened security has unintended and detrimental consequences to the host.1 Although this maladaptive immune response is classically associated with noninfectious diseases, such as arthritis, gout, and lupus, uncontrolled inflammation is emerging as a causative factor in the development of cardiovascular disease as well. Atherosclerosis is a widely known condition in which the immune system causes harm to the host. Classically defined as a disease that is initiated by alterations in cholesterol metabolism and the subendothelial retention of low-density lipoproteins (LDL),2 we now know that activation of both innate and adaptive immunity participate in atherogenesis.3 Advanced atherosclerotic plaques are characterized by highly inflammatory lesions that can both impede blood flow and precipitate thrombosis because of plaque rupture, leading ultimately to the clinical manifestations of atherosclerosis: myocardial infarction, and stroke. The progression of atherosclerosis in humans is associated with increased circulating levels of proinflammatory C-reactive protein, as well as increased white blood cell count.3,4 A considerable amount of evidence implicates the innate immune system in the progression of atherosclerosis.5 Recent studies suggest that polymorphonuclear neutrophils (PMNs) drive the accumulation of monocytes in atherosclerotic lesions in a manner dependent on PMN granule proteins, such as the cathelicidins (ie, cathelicidin-related antimicrobial peptide).6–9 Other comorbidities, such as hyperglycemia, also contribute to the mobilization of PMNs from the bone marrow during atherosclerosis progression.10 Interestingly, the PMN/lymphocyte ratio may have value in predicting future cardiovascular events over the white blood cell count alone.11 Although the role of PMNs in atherogenesis is emerging, the roles …
The era of incremental change in the technology innovation life cycle: An analysis of the automotive emission control industry

Abstract According to the life cycle model of technological evolution, after the emergence of a dominant design, technological product industries undergo an “era of incremental change.” This era of incremental change is not well understood in the existing literature. Although the period is typically characterized in terms of stability and minimal innovation, we find that the era of incremental change can be actually quite dynamic. Through our research into the period of time following the emergence of a dominant design in automotive emission control systems, we find that the overall product innovation in the industry did not decline immediately following the dominant design, and increased throughout the era of incremental change. Further, we find that firms maintain their attention on the same core components that they innovated upon before the dominant design, but that these components make up less of the overall proportion of total innovation throughout the era of incremental change. Finally, we found that the concentration of innovating firms in the industry increases immediately following the dominant design, and this concentration decreases over time throughout the era of incremental change. Findings imply a pattern of contraction and expansion in the era of incremental change that extends previous work on the technological product life cycles and helps to characterize the era of incremental change in a novel way.
Migration of [RuII(hedta)]− among three binding sites on 6-azauridine

[Ru(hedta)(H2O)]− reacts with 6-azauridine over an essential Zn/Hg surface at N-6 of the ligand in less than 5.0 min. This species has a characteristic H-1′ ribofuranosyl 1H NMR resonance at 5.72 ppm and a related C-5H pyrimidine resonance at 4.39 ppm. This N-6 complex has a RuII<III electrochemical wave at −0.06 V versus NHE. The N-6 bound species rearranges to C-5-N-6 η2 coordination with T12∼2.5 h. The η2 form has a characteristic H-1′ 1H NMR resonance at 5.45 ppm and a very highly stabilized RuII center having a RuII/III electrochemical wave at 1.33 V. If the pH or pD is above 6.0, the η2 complex further migrates to the N-3 position of 6-azauridine which has ionized to its anion at N-3. The N-3 form becomes bidentate with N-3, O-4 chelation as observed previously for [RuII(hedta)]− for uridine. The chelated N-3, O-4 form has a RuIII/IV wave at 0.94 V which can be eliminated by making the solution acidic and forcing N-3 only coordination, or remigration to the η2 form. If the synthetic sequence is carried out with pD below 3.0, the η2 form can be prepared in nearly quantitative yield. Under these conditions the 3C NMR spectra reveal carbon resonances for the pyrimidine ring which are shifted 0.0 ppm compared to the free ligand for the η2 carbon (C-5), and downfield shifts of 3.0 ppm for C-4 and 3.7 ppm for C-2 relative to 6-azauridine. Therefore η2 attachments at C = N units do not show the 40 to 80 ppm upfield shifts observed for C = C units of olefins.
Existential Transcendence in Late Modernity: Edgework and Hermeneutic Reflexivity

Increasing attention to existentialist thought by criminologists and other social scientists in recent decades has created an opportunity to envision new possibilities in critical theoretic inquiry that extend well beyond the classical formulations of this tradition. In this essay, I draw on existentialist ideas to outline a critical perspective rooted in recent developments associated with Ulrich Beck’s notion of “risk society” and the related theory of reflexive modernization. I argue that, though the detraditionalization consequences of reflexive modernization give greater scope to agency in the risk society, transcendence in the existentialist sense is found in the hermeneutic reflexivity one experiences in high risk practices I call “edgework”. Finally, I explore several options for using existential transcendence in hermeneutic reflexivity as a reference for critical analysis and, in doing so, suggest an alternative to Beck’s own critical approach—cosmopolitanism—as a foundation for a critical theory of the second modern social order.
Historically black college and university operating cost efficiencies: stochastic cost estimates and comparisons to predominately white institutions

This paper compares operating cost efficiencies of public historically black colleges and universities to those of predominately white institutions in the USA. Panel data spans four academic years, 2005 to 2006 through 2008 to 2009. Cost frontiers are estimated with an inefficiency component that includes institutional specific environmental factors. Results indicate that historically black institutions have some cost advantages over their predominately white counterparts, but on average suffer higher operating inefficiencies. Comparisons are made as to the extent to which student retention, faculty tenure, and state government funding contribute to cost inefficiencies. Inefficiency growth among black universities appears to have outstripped those of white institutions through 2007 to 2008. Yet, in 2008 to 2009 historically black universities made substantial efficiency improvements while predominately white institutions experienced a high inefficiency growth. Given the historically black contributions to educational and economic development, the inquiry and results should be of wide managerial and public policy interest.
Brain and behavior in 48, XXYY syndrome

The phenotype of 48, XXYY syndrome (referred to as XXYY) is associated with characteristic but variable developmental, cognitive, behavioral and physical abnormalities. To discern the neuroanatomical phenotype of the syndrome, we conducted quantitative and qualitative analyses on MRI brain scans from 25 males with XXYY and 92 age and SES matched typically developing XY males. Quantitatively, males in the XXYY group had smaller gray and white matter volumes of the frontal and temporal lobes. Conversely, both gray and white matter volumes of the parietal lobe as well as lateral ventricular volume were larger in the XXYY group. Qualitatively, males in the XXYY group had a higher incidence of colpocephaly (84% vs. 34%, p ≤ 0.001), white matter lesions (25% vs. 5%, p = 0.007), and thin posterior body of the corpus callosum (28% vs. 3%, p = 0.001). The specificity of these findings may shed light on the role of the X and Y chromosomes in typical and atypical brain development and help provide direction for future studies of brain–behavior relationships in males with XXYY syndrome.
We Need Better Classification and Terminology for “People at High Risk of or in the Process of Developing Lupus”

Systemic lupus erythematosus (SLE), like rheumatoid arthritis (RA) and other connective tissue diseases (CTDs), does not develop on the day it is diagnosed. Rather, as rheumatologists know, the onset can be days to years before SLE is clinically diagnosed. The recognition of SLE, a prototypic autoimmune disease with a striking heterogeneity and range of manifestations, can be a challenge1, 2. In some individuals, full-blown disease, with a “full house” of autoantibodies and aggressive, life-threatening disease, such as lupus nephritis or vasculitis, seems to develop overnight. In others, however, the onset is insidious and difficult to recognize and to distinguish from other conditions. The diagnosis of SLE among patients seen in consultation, most often for a positive antinuclear antibody (ANA) and one or two other non-specific symptoms, such as arthralgias, myalgias, fatigue or rashes, is one of the common clinical challenges faced by rheumatologists. The challenge is compounded by the fact that SLE is likely a spectrum of related diseases that share immunologic and clinical features.
Technical and biological modifications for enhanced flexor tendon repair

Clinical outcomes after intrasynovial flexor tendon repair have been substantially improved over the past 2 decades through advances in tendon suture techniques and postoperative rehabilitation methods. Nevertheless, complications such as repair site elongation (i.e., gap formation) and rupture continue to occur frequently. Experimental studies have shown that repair site strength fails to increase in the first 3 weeks after tendon suture. After 3 weeks, the strength and rigidity of the repair site improve significantly, a process that continues for several months. Formation of a repair site gap during the early rehabilitation period has been shown to considerably delay the accrual of repair site strength over time. Thus, it is of prime importance that the method of tendon suture achieves and maintains a stiff and strong repair site during the early healing interval by maintaining close approximation of the tendon stumps and by stimulating, where possible, the intrinsic repair response. In this review, we describe recent efforts to enhance the integrity of the immature repair site. We focus on 2 major areas of advancement: surgical technique modifications and manipulation of the biologic and biochemical environment.
Species Differentiation on a Dynamic Landscape: Shifts in Metapopulation Genetic Structure Using the Chronology of the Hawaiian Archipelago

Species formation during adaptive radiation often occurs in the context of a changing environment. The establishment and arrangement of populations, in space and time, sets up ecological and genetic processes that dictate the rate and pattern of differentiation. Here, we focus on how a dynamic habitat can affect genetic structure, and ultimately, differentiation among populations. We make use of the chronology and geographical history provided by the Hawaiian archipelago to examine the initial stages of population establishment and genetic divergence. We use data from a set of 6 spider lineages that differ in habitat affinities, some preferring low elevation habitats with a longer history of connection, others being more specialized for high elevation and/or wet forest, some with more general habitat affinities. We show that habitat preferences associated with lineages are important in ecological and genetic structuring. Lineages that have more restricted habitat preferences are subject to repeated episodes of isolation and fragmentation as a result of lava flows and vegetation succession. The initial dynamic set up by the landscape translates over time into discrete lineages. Further work is needed to understand how genetic changes interact with a changing set of ecological interactions amongst a shifting mosaic of landscapes to achieve species formation.
Are common measures of dietary restraint and disinhibited eating reliable and valid in obese persons

Disordered eating measures were developed and validated in primarily normal weight samples; thus, it is unclear if the psychometric properties are equivalent across weight groups. This study evaluated the reliability and validity of self-reported disinhibited eating and dietary restraint measures in a community-recruited sample of overweight individuals (N = 201) and obese individuals (N = 101) and normal weight matched controls. Coefficient alpha and average inter-item correlations were used to test internal consistency reliability. Correlations between lifetime disordered eating behaviors and measures of dietary restraint and disinhibited eating were used to test convergent validity. Disordered eating measures included: Eating Disorders Examination Questionnaire (EDE-Q), Three Factor Eating Questionnaire (TFEQ), Dutch Eating Behavior Questionnaire (DEBQ), Eating Disorders Inventory-3 (EDI-3), and Restraint Scale. Correlations between lifetime disordered eating behaviors and measures of non-disordered-eating-related psychopathology were used to test discriminant validity. Results indicated that most measures demonstrated acceptable internal consistency reliability across groups, with the exception of the Restraint Scale. Significantly higher convergent correlations between lifetime history of fasting and TFEQ Cognitive Restraint emerged for the overweight vs. obese group, and the magnitude of discriminant correlations between lifetime history of binge eating and the Inventory of Depression and Anxiety Symptoms (IDAS) Well Being scale was stronger in the normal weight vs. overweight group. Findings suggest the majority restrained and disinhibited eating measures are reliable and valid among weight groups, and are suitable to use in overweight and obese populations.
The effect of m-xylene on rat lung benzo[a]pyrene metabolism and microsomal membrane lipids: comparison with p-xylene.

Abstract m -Xylene (1 g/kg, i.p., 1 h) was shown to decrease aryl hydrocarbon hydroxylase (AHH) activity, a detoxification pathway for benzo[ a ]pyrene (BaP), in the rat lung. Inhibition was maximal at 1 g/kg, 1 h after treatment and was sustained for at least 24 h. Reduction in cytochrome P -450 activity in rat lung was also observed, while liver activity was unchanged. p -Xylene has been previously shown to produce a similar pattern of MFO changes in rat brain. The lipid composition of the microsomal membrane is important to mixed function oxidase (MFO) regulation and function. Since the xylenes are lipophilic, these compounds were studied to determine whether they alter pulmonary microsomal lipids. p -Xylene produced an organ specific increase in lipid peroxidation in the rat lung. This was accompanied by decreases in lung microsomal total phospholipid (PL) and phosphatidylcholine (PC) content. Pulmonary microsomal membrane fluidity was also reduced by p -xylene administration. In comparison, m -xylene administration did not change any of the lipid membrane parameters tested. These divergent results leave unresolved the role of altered PL metabolism in solvent-induced inhibition of MFO activity.
Action of mianserin and zimelidine on the norepinephrine receptor coupled adenylate cyclase system in brain: Subsensitivity without reduction in β-adrenergic receptor binding

The present experiments were undertaken to ascertain whether non-tricyclic, clinically effective, antidepressant drugs such as the tetracyclic mianserin and the serotonin uptake inhibitor, zimelidine, cause alterations of central noradrenergic receptor systems similar to those elicited by classical tricyclic antidepressants, MAO inhibitors and ECT. Like desipramine (DMI), mianserin and zimelidine caused, after chronic administration, a significant reduction in the sensitivity of the cyclic AMP response to (R)-norepinephrine while a single dose of the drugs did not affect the neurohormonal response. The basal levels of the nucleotide were not changed by the antidepressant drugs following acute or chronic administration. While the noradrenergic subsensitivity caused by DMI was linked to a reduction in the Bmax value of 3H-dihydroalprenolol binding, the subsensitivity caused by mianserin and zimelidine was not associated with a decreased density of β-adrenergic receptors. In accord with these data on β-adrenergic receptor binding, the responsivenss of the adrenergic cyclic AMP generating system to the β-adrenergic agonist, (R)-isoproterenol, was significantly reduced following chronic treatment with DMI but not with mianserin or zimelidine. The results provide further evidence for the theory that the delayed therapeutic action of different prototypes of antidepressant treatments may be related to the delayed change in noradrenergic receptor function and that a reduction in the density of β-adrenergic receptors is only one mechanism by which the sensitivity of the system is regulated.
College course scarcity and time to degree

Abstract College students are taking longer to earn baccalaureate degrees now than ever before, but little is known about institutional factors that may contribute to this trend. In this paper we investigate an important institutional constraint—course scarcity—that we hypothesize may be associated with increased time to degree. We employ a unique administrative dataset from a large, moderately selective, public institution and use an instrumental variables approach, identifying off the random registration times assigned to students. Results suggest that course scarcity does not delay students’ graduation. We explore alternative explanations for our findings and discuss a variety of other factors correlated with time to baccalaureate completion.
StartX and the ‘Paradox of Success’: Filling the gap in Stanford’s entrepreneurial culture

Stanford University’s legendary success in technology transfer, based upon a relatively small group of serial faculty entrepreneurs, masked unrealized potential residing in the underutilized inventions of less entrepreneurially experienced faculty and students. An optimum academic entrepreneurship and technology-transfer regime matches various levels of inventor interest and involvement with appropriate organizational competence and support. The ‘Paradox of Success’ is that great organizational success in licensing, or other activities, may reduce the motivation to further advancement, in the Stanford case, introducing support structures for research commercialization that are commonplace in aspiring entrepreneurial universities. Stanford had largely bought into an ideology of a self-organizing innovation ecosystem in Silicon Valley that implied lack of need for explicit entrepreneurial support structures on campus, such as incubator facilities. This belief inhibited policy intervention until a student-or...
Fractional quantum hall effect: Even denominators in odd places

Odd-denominator fractional quantum Hall states are routinely observed in high-mobility gallium arsenide heterostructures. Now, a 5/2 state has been observed in an oxide heterostructure — an unexpected state in an unexpected material.
Asymmetric syntheses of 1-deoxy-6-epicastanospermine and rhamno-1-deoxynojirimycin.

The concise and highly diastereoselective synthesis of the titles azasugars was accomplished using nonracemic bicyclic lactams. Chirality 10:88–90, 1998. © 1998 Wiley-Liss, Inc.
Breast cancer-associated mutations in metalloprotease disintegrin ADAM12 interfere with the intracellular trafficking and processing of the protein.

ADAM12 has recently emerged as a Candidate Cancer Gene in a comprehensive genetic analysis of human breast cancers. Three somatic mutations in ADAM12 were observed at significant frequencies in breast cancers: D301H, G479E and L792F. The first 2 of these mutations involve highly conserved residues in ADAM12, and our computational sequence analysis confirms that they may be cancer-related. We show that the corresponding mutations in mouse ADAM12 inhibit the proteolytic processing and activation of ADAM12 in NIH3T3, COS-7, CHO-K1 cells and in MCF-7 breast cancer cells. The D/H and G/E ADAM12 mutants exert a dominant-negative effect on the processing of the wild-type ADAM12. Immunofluorescence analysis and cell surface biotinylation experiments demonstrate that the D/H and G/E mutants are retained inside the cell and are not transported to the cell surface. Consequently, the D/H and G/E mutants, unlike the wild-type ADAM12, are not capable of shedding Delta-like l, a ligand for Notch receptor, at the cell surface, or of stimulating cell migration. Our results suggest that the breast cancer-associated mutations interfere with the intracellular trafficking of ADAM12 and result in loss of the functional ADAM12 at the cell surface. © 2008 Wiley-Liss, Inc.
Globalization of scientific and engineering talent: international mobility of students, workers, and ideas and the world economy

This paper documents the five main ways in which globalization of scientific and engineering has proceeded: (1) expansion of mass higher education worldwide; (2) growth in number of international students; (3) immigration of scientists and engineers; (4) non-immigration trips: academic visitors, conferences; (5) greater international co-authorship and co-patenting. It is argued that by accelerating the rate of technological change and speeding the adoption of best practices around the world, these developments should benefit advanced and developing countries but that they threaten the comparative advantage of advanced countries in high-tech sectors and the edge that their citizens have in access to the highest quality university education and jobs; and risk creating greater divisions between modern and traditional sectors in developing countries. How economies around the world take advantage of the benefits and minimize the costs of globalization of knowledge will be a major determinant of economic progress.
Unified Treatment of Natural Convection in Tall Narrow and Flat Wide Rectangular Enclosures

Numerical simulation was used to investigate natural convection in rectangular enclosures ranging in aspect ratio from tall, narrow shapes to flat, wide shapes. For each of the selected aspect ratios, the Rayleigh number was varied over a range of approximately four decades. Two fundamental thermal boundary conditions were considered. One of these, commonly designed as heating from below, involved the imposition of a temperature at the lower bounding wall that is higher than that at the upper bounding wall. The side walls of the enclosure were maintained adiabatic for this case. The second employed boundary condition was side walls at different uniform temperatures and adiabatic upper and lower boundaries. For each aspect ratio and for both types of boundary conditions, the onset of natural convection from the regime of pure conduction occurred at a definitive value of the Rayleigh number, termed the critical Rayleigh number. Once that threshold value was exceeded, the Nusselt number increased markedly wi...
A review of power electronics interfaces for distributed energy systems towards achieving low-cost modular design

Due to increased attention towards clean and sustainable energy, distributed energy (DE) systems are gaining popularity all over the world. Power electronics are an integral part of these energy systems being able to convert generated electricity into consumer usable and utility compatible forms. But the addition of power electronics adds costs to the DE capital investments along with some reliability issues. Therefore, widespread use of distributed energy requires power electronics topologies that are less expensive and more dependable. Use of modular power electronics is a way to address these issues. Adoption of functional building blocks that can be used for multiple applications results in high volume production and reduced engineering effort, design testing, onsite installation and maintenance work for specific customer applications. In this paper, different power electronics topologies are reviewed that are typically used with distributed energy systems. The integrated power electronics module (IPEM) based back-to-back converter topologies are found to be most suitable interface that can operate with different DE systems with small or no modifications. Also the requirements for a hierarchical control structure with standardized power and communication interfaces are addressed in the paper along with some discussion on future design possibilities for the IPEM-based power electronics topologies. It is expected that modular and flexible power electronics and standardized controls and interfaces, will provide commonality in hardware and software for the power electronics interfaces, thus will enable their volume production and decrease their cost share in distributed energy applications.
Energetic and thermal performance of high-gain diode-side-pumped Nd:YAG rods

We investigated the energetic and thermal performance of a diode-side-pumped Nd:YAG rod laser with up to 50 W power deposited as excess heat into a 3-mm-diameter, 10-cm-length rod. The rod design produces an extremely flat gain profile resulting in “textbook” expressions of thermal lensing and birefringence. Thermal and energetic measurements are compared to corresponding “textbook” theoretical expressions. Discrepancies between various published thermo-mechanical YAG parameters are resolved by a self-consistent set of measured and calculated data for rod thermal lens focal lengths, birefringence depolarization and ratio of heat to stored energy (χ). Measured thermal and energetic performance under lasing and nonlasing conditions are presented, which agree with published theoretical expressions and measurements. Compensation of rod thermal lensing with simple spherical concave lenses is demonstrated. In addition various methods for compensating birefringence depolarization are theoretically and experimentally analyzed and compared.
Extensions between simple modules for Frobenius kernels

Introduction Let G be a simply connected and connected semisimple group over an algebraically closed field k of characteristic p > 0. T ⊂ G is a maximal torus and R is the root system relative to T . X(T ) is the weight lattice. Let B ⊃ T be a Borel subgroup corresponding to the negative roots R− = R. Denote by Gr the r-th Frobenius kernel of G. The socle and radical structures of the cohomology groups of line bundles on the flag variety G/B are determined by those structures of the GrT -modules Zr(λ) = Ind GrT BrTλ (cf. [12]). So the study of the GrT -structure of these modules turns out to be more interesting. Calculation of the extensions between simple modules plays an important rule in determining the socle structure. In this paper, we calculate the socle series of the Weyl modules with p-singular highest weight for the group of type G2 by studying the extensions between simple modules for Frobenius kernel. In the first section of this paper, we study the properties of Ext Gr(L(μ), H (λ)), which turns out to be semisimple and to have a good filtration for large p and prestricted weights μ and λ. Some of the vanishing properties of these modules are also studied. Then we use these properties to calculate Ext Gr(L(μ), L(λ)), which will lead a calculation of the extensions between simple GrT -modules. The results in this section will be used in Section 3 to calculate the socle series of Z1(λ) with p-singular weights λ for the group of type G2. The author ([13] ch3) used the method of Doty and Sullivan [7] and calculated the socle series of H(λ) for the p-singular weights λ in the bottom p-alcove for the groups of type A2 and B2. However when the multiplicities of simple modules in
RENAL TISSUE OXYGENATION FOLLOWING INDUCED HYPOTENSION IN DOGS

Renal oxygenation was studied during indnrrd hypotension in mongrel dogs, anaesthetized with 1–1.5% halothane in oxygen. Hypotension was induced with an infusion i.v. of sodium nitroprusside (SNP) 70±l7 μg kg-1 −1 min −1 (mean±SEM) or trimetaphan (TMP) 36±16 μg kg −1 min −1 , or by controlled arterial haemorrhage (45±6 ml/kg of body weight). Mean arterial pressure (MAP), cortical ( P ct 2 ) and medullary ( P mt O 2 ) tissue oxygen tensions, arterial ( P a O 2 ), renal venous ( P rv O 2 ), and urine P u O 2 ) oxygen tensions were measured during the 40-min control, hypotension, and recovery periods. MAP was decreased to approximately 60% of the control value, P ct O 2 decreased significantly ( P P mt O 2 decreased significantly only in the haemorrhage group. Upon restoration of MAP to normal values, renal tissue oxygen tensions recovered in all groups, somewhat more rapidly in the SNP group. There were no significant differences in P a O 2 , P rv O 2 and P uO 2 during control, hypotension and recovery periods in the three groups. Tissue oxygen tension values followed the changes in MAP; but were not hypoxic, leading us to believe that both SNP and TMP are hypotensive agents safe for the kidney
Reducing the number of reader interpretations in MRMC studies.

Rationale and Objectives Multireader, multicase (MRMC) receiver-operating characteristic studies often require large numbers of patients, readers, and reader interpretations. The objective of this work is to evaluate a new “mixed” MRMC study design that reduces the number of reader interpretations. Materials and Methods As compared to the traditional MRMC design, the number of reader interpretations and the number of cases that must be truth-verified for the new mixed design was evaluated theoretically and empirically for various correlation values and sample sizes. Results For large MRMC studies, the new mixed design offers a substantial savings in the number of reader interpretations if the magnitude of the difference in between-reader correlations is not zero. For example, compared to a traditional design with 20 readers, 200 total cases, and a difference in between-reader correlations of 0.05, the newly proposed mixed design requires each reader to interpret only 132 cases, but at a cost of truth-verifying an additional 64 cases. Conclusions The mixed design can reduce the number of cases that readers need to interpret and the overall duration of a study, but at a cost in terms of the number of cases that must be truth-verified. The mixed design is particularly useful for studies where the condition being detected is not rare and patients routinely undergo the gold standard assessment.
When is a picture not worth a thousand words? The psychological effects of mediated exposure to a remote location

The Internet has radically decreased the influence of physical distance by allowing people to share images and information about distant places at the click of a button. But we still do not understand how exposure to this information influences our mental conception of places that are far away, and how these effects may change our attitudes towards distant locations. This has implications for both tourism marketers and travelers consulting social media sites for information on destinations. We conducted an experiment to see if exposing participants to one of four mediated representations of an unfamiliar environment impacted their attitudes towards the location. We found that mediated exposure to a distant place positively influenced desire to visit the location through different routes: 3D panoramas heightened feelings of spatial presence which translated into more positive attitudes towards the place, while textual descriptions decreased psychological distance which in turn was associated with more positive attitudes.
Neurobehavioural sequelae of cardiopulmonary bypass

The development of coronary artery bypass grafting (CABG) and its effect on angina is the product of a series of technical and scientific advances. Despite these advances, however, adverse neurobehavioural outcomes continue to occur. Stroke is the most serious complication of CABG, but studies that have identified demographic and medical risk factors available before surgery are an important advance. Short-term cognitive deficits are common after CABG, but may not be specific to this procedure. However, deficits in some cognitive areas such as visuoconstruction persist over time, and may reflect parieto-occipital watershed area injury secondary to hypoperfusion or embolic factors. Risk factors for cognitive decline may be time dependent, with short-term studies identifying factors that differ from those of long-term studies. Patients with depression before surgery are likely to have persistent depression afterwards. However, depression does not account for the cognitive decline after CABG. Since CABG is increasingly done in older patients with more comorbidity, the challenge is to identify patients at risk of adverse neurocognitive outcomes and to protect them by modification of the surgical procedure or by effective medical therapy.
Simulation of Semiconductor Nanostructures

We employ density functional and quantum Monte Carlo calculations to show that significant changes occur in the optical gap of fully hydrogenated nanoclusters when the surface contains impurity passivants such as atomic oxygen. Our results show that quantum confinement is only one mechanism responsible for visible photoluminescence in silicon nanoclusters and that the specific surface chemistry must be taken into account in order to interpret experimental results. In the case of oxygen, the gap reduction computed as a function of the nanocluster size provides a consistent interpretation of several recent experiments. Furthermore, we predict that other double bonded groups also significantly affect the optical gap while single bonded groups have a minimal influence.
Model-based control of continuous-time systems with limited intermittent feedback

This paper presents a practical alternative for the implementation of Model-Based Networked Control Systems (MB-NCS) with intermittent feedback. Our approach does not require continuous communication over a limited bandwidth channel during the closed-loop time intervals; instead, we propose a communication format that implements a fast rate for updating the state of the model. During the closed-loop interval the sensor transmits measurements at a fast rate but without assuming continuous communication. We consider uncertain continuous-time systems and study the state feedback and output feedback cases. For both cases, we provide necessary and sufficient conditions for stability as a function of the update periods.
Prevalence of obesity and contributing factors among Sherpa women in urban and rural Nepal.

Dietary and lifestyle changes have profound influences on the body mass and nutritional status of individuals living in developed countries. This report used data from a prospective longitudinal study to assess the prevalence of obesity among Sherpa women and to determine which factors were most predictive of it. The body mass index (BMI), energy consumption and expenditures, and physical activity patterns were compared for nonpregnant, premenopausal women living in urban low altitude (n = 216); urban high altitude (n = 56); and rural high altitude (n = 93) settings. Area of residence was highly predictive of the BMI. The mean body weight and BMI were significantly higher for the urban low altitude sample (53.3 kg and 23.5 kg/m2 , respectively) than for the total high altitude sample (51.4 kg and 21.8 kg/m2 , respectively). The rural, high altitude sample had the lowest mean body weight (50.1 kg), triceps skinfold (18.5 mm), and BMI (21.3 kg/m2 ). Although mean BMI was in the range associated with the overall lowest risk to health, distribution of the BMI showed that 29% of the urban low altitude sample were classified obese. The prevalence of obesity was correlated with reduced energy expenditure, not to an increase in consumed calories. Reduced energy expenditures appear to be related to shifts in occupation, access to motorized transportation, and increased affluence, which has allowed Sherpas to hire servants to do manual labor. These data suggest that Sherpa women may potentially be at risk of chronic health problems in the future because of increased adiposity. Am. J. Hum. Biol. 10:519-528, 1998. © 1998 Wiley-Liss, Inc.
The automobile fuel economy standards: Are they cost-effective?

The September 24, 1979 issue of the New York Times carried on the front page of the business section an article by Edwin McDowell entitled “U.S. Fuel Standards Questioned.” The story described a study by Harbridge House, “a Boston-based management consulting and research firm.” According to McDowell, the Harbridge House analysis
Demonstration of Spectral Defragmentation in Flexible Bandwidth Optical Networking by FWM

Flexible bandwidth elastic optical networking is an attractive solution for efficiently matching allocated bandwidth with link demand, but suffers from inevitable spectral fragmentation. In this letter, we discuss spectral defragmentation in flexible bandwidth networks using four-wave mixing (FWM) and wavelength selective switch (WSS)-based wavelength conversion blocks. Simulations show a defragmentation degree of one (i.e., the number of defragmentation blocks equals one) results in 71% and 47% reductions in blocking probability under high offered load (680 Erlangs) and low offered load (220 Erlangs), respectively. Further reductions in blocking probability result from an increased defragmentation degree. Experimental results show spectral defragmentation over 500 GHz of bandwidth for a defragmentation degree of one, validating FWM- and WSS-based spectral defragmentation in flexible bandwidth networks.
Boosting and hard-core sets

This paper connects two fundamental ideas from theoretical computer science hard-core set construction, a type of hardness amplification from computational complexity, and boosting, a technique from computational learning theory. Using this connection we give fruitful applications of complexity-theoretic techniques to learning theory and vice versa. We show that the hard-core set construction of R. Impagliazzo (1995), which establishes the existence of distributions under which boolean functions are highly inapproximable, may be viewed as a boosting algorithm. Using alternate boosting methods we give an improved bound for hard-core set construction which matches known lower bounds from boosting and thus is optimal within this class of techniques. We then show how to apply techniques from R. Impagliazzo to give a new version of Jackson's celebrated Harmonic Sieve algorithm for learning DNF formulae under the uniform distribution using membership queries. Our new version has a significant asymptotic improvement in running time. Critical to our arguments is a careful analysis of the distributions which are employed in both boosting and hard-core set constructions.
Endovascular Aortic Aneurysm Repair with Carbon Dioxide Guided Angiography in Patients With Renal Insufficiency

Objective Renal dysfunction following endovascular abdominal aortic aneurysm repair (EVAR) remains a significant source of morbidity and mortality. We studied the use of carbon dioxide (CO 2 ) as a non-nephrotoxic contrast agent for EVAR. Methods Recorded data from 114 consecutive patients who underwent EVAR with CO 2 as the contrast agent over 44 months were retrospectively analyzed. CO 2 was used exclusively in 72 patients and in an additional 42 patients iodinated contrast (IC) was given (mean, 37 mL). Renal and hypogastric artery localization and completion angiography were done with CO 2 in all patients, including additional arterial embolization in 16 cases. Preoperative National Kidney Foundation glomerular filtration rate (GFR) classification was normal in 16 patients, mildly decreased in 52, moderate to severely decreased in 44, and two patients were on dialysis. Results All graft deployments were successful with no surgical conversions. CO 2 angiography identified 20 endoleaks (two type 1, 16 type 2, and two type 4) and three unintentionally covered arteries. Additional use of IC in 42 patients did not modify the procedure in any case. When compared with a cohort of patients who underwent EVAR using exclusively IC, the operative time was shorter with CO 2 (177 vs 194 minutes; P = .01); fluoroscopy time was less (21 vs 28 minutes; P = .002), and volume of IC was lower (37 vs 106 mL; P 2 use. Among patients with moderate to severely decreased GFR, those undergoing EVAR with IC had a 12.7% greater decrease in GFR compared with the CO 2 EVAR group ( P = .004). At 1, 6, and 12-month follow-up, computed tomography angiography showed well-positioned endografts with the expected patent renal and hypogastric arteries in all patients and no difference in endoleak detection compared with the IC EVAR group. During follow-up, eight transluminal interventions and one open conversion were required, and no aneurysm-related deaths occurred. Conclusions CO 2 -guided EVAR is technically feasible and safe; it eliminates or reduces the need for IC use, may expedite the procedure, and avoids deterioration in renal function in patients with pre-existing renal insufficiency. A prospective trial comparing CO 2 with IC during EVAR is warranted.
Osteotomy for digital deformity

Osteotomy may be indicated in digital phalanges to correct angular or rotational deformity resulting from malunited fracture, epiphyseal arrest, or congenital or developmental causes. The use of fine power tools facilitates precise correction. Lateral angulation is corrected by closing wedge osteotomy, dorsal angulation by opening wedge and bone graft, rotational deformity by transverse osteotomy, and derotation through the involved phalanx. Smooth Kirschner wires stabilize the osteotomies to permit early joint motion. These procedures can safely be performed in children.