cssi/SciSciGPT-SciSciNet huggingface dataset:
Small non-coding RNAs: from trash to treasure.

Desde a descoberta do primeiro microRNA em 1993, nosso conhecimento de RNAs nao-codificantes cresceu exponencialmente. Antes vistos como lixo transcricional, dada a falta de traducao em proteinas, os RNAs nao-codificantes sao hoje conhecidos por desempenhar relevantes papeis biologicos–. Diversos tipos de RNAs nao codificantes foram descobertos, os mais proeminentes incluem RNAs longos nao-codificantes, microRNAs (miRNA) e pequenos RNAs de interferencia (siRNA). O primeiro miRNA descoberto foi descrito no nematodeo C. elegans, e vinte e seis anos depois, existem mais de [...]
Abstract 201: Roles of PIKfyve in Cardiac Fibroblast Migration

Cell migration is fundamental to proper development of the heart as well as other organs. Our characterization of a hypomorphic PIKfyveβ-geo/β-geo mouse mutant, revealed that has an abnormally smal...
Inference of Population Genetic Structure and High Linkage Disequilibrium Among Alternaria spp. Collected from Tomato and Potato Using Genotyping by Sequencing

ABSTRACT Genotyping by sequencing (GBS) is considered a powerful tool to discover single nucleotide polymorphisms (SNPs), which are useful to characterize closely related genomes of plant species and plant pathogens. We applied GBS to determine genome-wide variations in a panel of 187 isolates of three closely related Alternaria spp. that cause diseases on tomato and potato in North Carolina (NC) and Wisconsin (WI). To compare genetic variations, reads were mapped to both A. alternata and A. solani draft reference genomes and detected dramatic differences in SNPs among them. Comparison of A. linariae and A. solani populations by principal component analysis revealed the first (83.8% of variation) and second (8.0% of variation) components contained A. linariae from tomato in NC and A. solani from potato in WI, respectively, providing evidence of population structure. Genetic differentiation (Hedrick’s G’ST) in A. linariae populations from Haywood, Macon, and Madison counties in NC were little or no differentiated (G’ST 0.0 - 0.2). However, A. linariae population from Swain county appeared to be highly differentiated (G’ST > 0.8). To measure the strength of the linkage disequilibrium (LD), we also calculated the allelic association between pairs of loci. Lewontin’s D (measures the fraction of allelic variations) and physical distances provided evidence of linkage throughout the entire genome, consistent with the hypothesis of non-random association of alleles among loci. Our findings provide new insights into the understanding of clonal populations on a genome-wide scale and microevolutionary factors that might play an important role in population structure. Although we found limited genetic diversity, the three Alternaria spp. studied here are genetically distinct and each species is preferentially associated with one host.
Potassium channel overexpression

Ion channels in the plasma membrane play a critical role in cellular function. These proteins are the gatekeepers that control ion homeostasis and shape excitability. Excitable cells use a variety of different ion channels to fashion their hallmark electrical signal, the action potential. Advances in molecular electrophysiology have led to the identification of more ion channel genes than there are identified membrane currents. This excess is particularly striking with potassium channels, where the wide diversity of genes is compounded by variable levels of hetero-multimerization, alternative splicing and post-translational modification. The classical methods of studying the roles of each gene rely either on exogenous expresison in frog oocytes or pharmacological manipulation of native currents. While these techniques have yielded a wealth of information concerning ion channel structure and function, they have come up short in linking individual genes and their products to physiology and disease.
Chapter 11 – Best practices

Publisher Summary This chapter discusses the best practices that may enable users to run their applications successfully on Oracle Real Application Clusters (RACs). Understanding the architecture is the initial step of implementing any technology. Yet, there is a great deal of confusion and misunderstanding in the marketplace around clustering in general. This creates some fundamental misconceptions about what RAC is and how it should be implemented. The next step in implementing a technology is understanding the hardware and software components that make up the architecture. The primary difference between stand-alone systems and clustered environments is interconnect and shared storage. The distinction between RAC and more traditional HA clusters takes this one step further, where the interconnect needs to be high bandwidth and low latency and the shared storage must be configured for shared concurrent access. The focus of the chapter is on the strategies and best practices for deploying applications on RAC, specifically leveraging the Oracle “Full Stack,” which includes Oracle Database 10g, RAC, Oracle Clusterware, and Automatic Storage Management (ASM). The discussion presented encompasses observations derived from the experiences of hundreds of customers currently running their applications in production on RAC.
The Effect of Aging on the Electrically Evoked Compound Action Potential.

Objectives To examine the effect of aging on electrically evoked compound action potential (eCAP) growth functions and their relationship with speech recognition in noise in cochlear implant (CI) users. Background Aging typically leads to difficulty understanding speech in background noise. Previous research has explored cognitive and central auditory mechanisms contributing to these age-related changes. However, it is likely that the peripheral auditory system may also play a role. One challenge is separating the effects of aging on cochlear structures from the effects of aging on the auditory nerve in humans. CI users provide a unique way to address this issue, as intracochlear electrical stimulation bypasses surviving hair cells and activates the auditory nerve directly. Studies in animal models suggest that age-related loss of spiral ganglion cells could lead to shallower eCAP growth functions and/or increased eCAP thresholds and potentially negatively impact speech recognition. Methods Ten younger and 10 older postlingually deafened, adult CI recipients participated in this study. eCAP amplitude-intensity functions were recorded from a mid-array electrode and fit using linear functions. Speech recognition in noise was assessed using the Quick Speech-in-Noise (QuickSIN) test. Results Older CI users had significantly shallower eCAP growth functions and higher eCAP thresholds than younger CI users. eCAP growth functions were not correlated with speech recognition in noise. Conclusion Results of this study suggest that older adults may have poorer neural survival, resulting in higher eCAP thresholds and shallower eCAP growth functions. These findings expand our understanding of mechanisms underlying age-related changes in the peripheral auditory system.
Calibrating Deep Neural Network Classifiers on Out-of-Distribution Datasets.

To increase the trustworthiness of deep neural network (DNN) classifiers, an accurate prediction confidence that represents the true likelihood of correctness is crucial. Towards this end, many post-hoc calibration methods have been proposed to leverage a lightweight model to map the target DNN's output layer into a calibrated confidence. Nonetheless, on an out-of-distribution (OOD) dataset in practice, the target DNN can often mis-classify samples with a high confidence, creating significant challenges for the existing calibration methods to produce an accurate confidence. In this paper, we propose a new post-hoc confidence calibration method, called CCAC (Confidence Calibration with an Auxiliary Class), for DNN classifiers on OOD datasets. The key novelty of CCAC is an auxiliary class in the calibration model which separates mis-classified samples from correctly classified ones, thus effectively mitigating the target DNN's being confidently wrong. We also propose a simplified version of CCAC to reduce free parameters and facilitate transfer to a new unseen dataset. Our experiments on different DNN models, datasets and applications show that CCAC can consistently outperform the prior post-hoc calibration methods.
Assessment of Glycemic Control in Veterans With Chronic Obstructive Pulmonary Disease and Type 2 Diabetes Mellitus on Inhaled Corticosteroid Therapy.

ObjectiveTo determine if the use of inhaled corticosteroid (ICS) therapy affects glycemic control in patients with chronic obstructive pulmonary disease (COPD) and type 2 diabetes mellitus (T2DM).B...
Gap Filling: Assessing the Constitutionality of Virtual Criminal Trials in Light of Ramos v. Louisiana

Court closures in response to the COVID-19 pandemic have led some to consider the possibilities of virtual jury trials, with at least one state court already conducting a virtual trial in a civil case. The Supreme Court’s recent decision in Ramos v. Louisiana, in which the Court held that jury verdicts must be unanimous, sheds light on the constitutionality of virtual trials in criminal cases. But the answer that Ramos suggests—that virtual criminal trials are unconstitutional—is difficult to square with the answer offered by constitutional theory. Though the author of the Court’s opinion in Ramos, Justice Neil Gorsuch, is ostensibly an originalist, originalist theory (reflected in the scholarship of, among others, Professors Larry Solum, Randy Barnett, and Jack Balkin) would seem to allow for virtual trials because that inquiry falls in the Constitution’s “construction zone.” The Constitution says nothing about whether jury trials must be in-person, affording legal actors greater (although not unlimited) latitude to adjust jury practices to take account of current circumstances. This essay compares the Ramos Court’s analysis to that of prominent originalists to preliminarily address whether virtual jury trials are constitutional. Additionally, through that comparison, this essay demonstrates the extent to which originalist theory has yet to succeed in shaping Supreme Court decision-making.
Chain-Selective Isotopic Labeling of the Heterodimeric Type III Secretion Chaperone, Scc4:Scc1, Reveals the Total Structural Rearrangement of the Chlamydia trachomatis Bi-Functional Protein, Scc4.

Scc4 is an unusual bi-functional protein from Chlamydia trachomatis (CT) that functions as a type III secretion system (T3SS) chaperone and an RNA polymerase (RNAP)-binding protein. Both functions require interactions with protein partners during specific stages of the CT developmental cycle. As a T3SS chaperone, Scc4 binds Scc1 during the late stage of development to form a heterodimer complex, which chaperones the essential virulence effector, CopN. During the early-middle stage of development, Scc4 regulates T3SS gene expression by binding the σ66-containing RNAP holoenzyme. In order to study the structure and association mechanism of the Scc4:Scc1 T3SS chaperone complex using nuclear magnetic resonance (NMR) spectroscopy, we developed an approach to selectively label each chain of the Scc4:Scc1 complex with the 15N-isotope. The approach allowed one protein to be visible in the NMR spectrum at a time, which greatly reduced resonance overlap and permitted comparison of the backbone structures of free and bound Scc4. 1H,15N-heteronuclear single quantum coherence spectra of the 15N-Scc4:Scc1 and Scc4:15N-Scc1 complexes showed a total structural rearrangement of Scc4 upon binding Scc1 and a dynamic region isolated to Scc1, respectively. Development of the chain-selective labeling approach revealed that the association of Scc4 and Scc1 requires partial denaturation of Scc1 to form the high affinity complex, while low affinity interactions occurred between the isolated proteins under non-denaturing conditions. These results provide new models for Scc4′s functional switching mechanism and Scc4:Scc1 association in CT.
Shock Troops and Shock Absorbers: IT Support and Emotional Labor in the Rationalizing University:

Drawing on 200 hours of observation at The Help Desk, an IT Support (ITS) unit at a medical school, and interviews with 30 ITS workers from across the university, this article shows how organizatio...
Particle Sizes, Shapes, and Specific Surface

Soil is a three-phase system. This chapter focuses on the solid phase, which is the permanent component of the soil. The soil's solid phase consists of mineral particles having various shapes and sizes, as well as amorphous compounds such as organic matter and hydrated iron oxides, which are generally attached to the particles. Soil particles are classified according to their sizes, and the soil is characterized as a whole in terms of the relative proportions of those size groups. The groups may differ from one another in mineral composition as well as in particle size. It is these attributes of the soil solid phase, particle size, and mineral composition that largely determine the nature and behavior of the soil, its internal geometry and porosity, its interactions with fluids and solutes, its compressibility, strength, and thermal regime. Soil texture and range of particle sizes in a soil carry both qualitative and quantitative connotations. Qualitatively, it represents the feel of the soil material, whether coarse and gritty or fine and smooth to the touch. An experienced soil classifier can feel, by rubbing the moistened soil with his fingers, whether it is coarse textured or fine textured, and can even assess, semiquantitatively, the textural class to which the soli belongs.
Roles of Diguanylate Cyclases and Phosphodiesterases in Motility and Biofilm Formation in Vibrio fischeri

This chapter first describes the biology of Vibrio fischeri and the environmental influences that may dictate its need for large numbers of proteins dedicated to cyclic di-GMP (c-di-GMP) control and function. Then, it presents a bioinformatic analysis of these c-di-GMP-associated proteins. Next, the chapter provides a brief description of flagellar biogenesis and the roles played in controlling that process by both the magnesium cation (Mg2+) and specific c-di-GMP-associated enzymes. Then, it outlines the current knowledge concerning the role of c-di-GMP in cellulose biosynthesis and biofilm formation in V. fischeri. Finally, the chapter presents models for the roles of c-di-GMP in biofilm formation and flagellar biogenesis. V. fischeri is a marine bioluminescent microorganism that exists both as a free-living organism in seawater and in associations with animals, including fishes and squids. The sequenced vibrios each contain a larger chromosome that is relatively conserved among the different species and a smaller chromosome that is quite divergent. Less is known about proteins predicted to be involved in c-di-GMP binding in V. fischeri. Motile V. fischeri cells contain a tuft of flagella at one pole. This arrangement contrasts with that of enterics, which assemble flagella randomly across their surface, a distribution termed peritrichous. The work described in the chapter is one of the few studies, along with those investigating YcgR and PleD, where a detailed investigation of c-di-GMP in motility is being pursued.
Rewriting Logic as a Semantic Framework for Concurrency: a Progress Report

This paper surveys the work of many researchers on rewriting logic since it was first introduced in 1990. The main emphasis is on the use of rewriting logic as a semantic framework for concurrency. The goal in this regard is to express as faithfully as possible a very wide range of concurrency models, each on its own terms, avoiding any encodings or translations. Bringing very different models under a common semantic framework makes easier to understand what different models have in common and how they differ, to find deep connections between them, and to reason across their different formalisms. It becomes also much easier to achieve in a rigorous way the integration and interoperation of different models and languages whose combination offers attractive advantages. The logic and model theory of rewriting logic are also summarized, a number of current research directions are surveyed, and some concluding remarks about future directions are made.
Introduction, history, and overview: The ‘methods’ to our madness

Publisher Summary The chapter discusses the relationship between methods and conceptual advances in marine microbiology. Revolutionary discoveries in marine microbiology during the past two decades have fundamentally changed the concepts of the structure and functioning of marine ecosystems. Early microbial oceanographers used the viable count and pure culture technique to determine the abundance, distribution, and species composition of bacteria. The culture technique was not enough, and a direct and quantitative ecosystem analysis was required. Then the emphasis on culture-independent methods to study natural microbial assemblages led to a flurry of biochemical methods for measuring bacterial (and total microbial) biomass and the physiological state of natural assemblages of marine microbes: ATP for total microbial biomass; lipopolysaccharide and muramic for bacterial biomass; electron transport system (ETS) activity as a proxy for microbial respiration; energy charge as a measure of the physiological state of the assemblage (for instance in response to ecosystem stress). Method refinement to measure respiration of natural bacterial or protozoan contributes to understanding microbial carbon cycling in the ocean. One of most influential techniques in microbial oceanography is Hans- Georg Hoppe's method for measuring bacterial ectohydrolase activities in intact planktonic. It has provided important insights and constraints on how the organic matter in particles and polymers become available for uptake by bacteria.
Lessons From Privatization Task Forces

This study provides evidence on an aspect of privatization that is increasing in popularity yet rarely considered in the literature: the effect that private-sector task forces have on privatization efforts. It uses case studies from Charlotte and Raleigh, North Carolina, to provide evidence on the role of task forces in reengineering government and suggests how future privatization efforts can benefit from this knowledge. Specifically, it suggests that task forces need to establish realistic timetables, understand that there are fundamental differences between the public and private sectors, and work without predetermined biases to achieve desired ends. In addition, they need to identify services that are appropriate for privatization, understand the nature of privatization, and accept both the strengths and weaknesses of it. While the results of privatization endeavors may vary, they may be enhanced by adopting a new awareness of how private-sector task forces influence privatization efforts.
Beyond the c-suite: corporate communications’ power and influence

Purpose – The purpose of this paper is to examine what formal executive-level committees senior corporate communications executives are members of and what value they contribute. Design/methodology/approach – The researcher conducted in-depth interviews with 30 senior executives at four US companies who discussed corporate communications’ involvement in eight strategic issues. Findings – The focus on the C-Suite is too narrow as strategic issues arise at the division level and in executive-level committees. Corporate communications is often in competition with marketing for influence and coveted seats in the board rooms. Corporate communications is most likely to be included in decision making when issues are perceived as falling within their domain, when the function has support from the CEO, when working in industries with frequent crises or those focussing on reputation management, and in companies that utilize integrated decision teams. Practical implications – Corporate communicators need to enhance ...
Cropland Allocation Decisions: The Role of Agricultural Commodity Programs and the Reclamation Program

This chapter describes and analyzes the role of Federal commodity programs and the U.S. Bureau of Reclamation (Reclamation) program in California agriculture. A behavioral model is developed of Reclamation water supply and commodity program provisions as determinants of cropland allocation decisions. The model is estimated econometrically using data from irrigation districts in California. Based on the results, two simulations illustrate cropland allocation responses to generic changes in Federal program provisions. By affecting crop supply, a simulated 10-percent reduction in California’s Reclamation water supply could result in 1–2 percent increases in the National market prices of rice and vegetables, while a simulated 0.05 decrease in wheat’s acreage reduction program would not affect National market prices.
Tangible Things: Harvard Collections in World History

A multivenue exhibition, Tangible Things: Harvard Collections in World History, which involved a treasure hunt through six museums on the Harvard University campus, posed provocative questions about the apparently arbitrary classification systems in which artifacts find final resting places. Tangible Things is certain to inspire a great deal of productive reflection and controversy among museum scholars.
AraL from B. subtilis is a sugar phosphatase and member of the nitrophenyl phosphatase family of the HAD superfamily (585.6)

The HAD (Haloacid Dehalogenase) superfamily is a diverse superfamily with a majority of the enzymes being phosphatases. One family of the HAD superfamily is the nitrophenyl phosphatase family, so n...
Immunochemical Studies with Synthetic Human Gastrin

Summary Antibodies to the gastrin molecule were evoked in rabbits by immunization with synthetic human gastrin I (2–17) conjugated to bovine serum albumin. The antibodies produced were of the γG-immunoglobulin class. A radioimmunoassay system for gastrin is described utilizing the precipitation of antibody-bound radioiodinated synthetic human gastrin I (2–17). The sensitivity of the immunoassay method is 5 μμg, a level of sensitivity anticipated to be sufficient to measure physiological levels of gastrin in human serum.
Effects of caffeine and coffee on fluid transport in the small intestine

Abstract Although caffeine is known to stimulate small intestinal water secretion in man, no available studies have examined the effect of coffee on small intestinal fluid transport. We have studied the effect of both coffee and caffeine on jejunal sodium and water transport by the triple lumen intestinal perfusion technique. Both caffeine and coffee solutions had equivalent caffeine concentrations, approximating the caffeine concentration in one cup of coffee. Control and coffee perfusion resulted in net absorption of 0.9 ± 0.2 and 1.1 ± 0.3 ml per min per 30 cm, respectively, whereas caffeine perfusion resulted in net water secretion of 2.4 ± 0.4 ml per min per 30 cm ( P P
TULIP: A link-level protocol for improving TCP over wireless links

We present the transport unaware link improvement protocol (TULIP), which dramatically improves the performance of TCP over lossy wireless links, without competing with or modifying the transport- or network-layer protocols. TULIP is tailored for the half-duplex radio links available with today's commercial radios and provides a MAC acceleration feature applicable to collision-avoidance MAC protocols (e.g., IEEE 802.11) to improve throughput. TULIP's timers rely on a maximum propagation delay over the link, rather than performing a round-trip time estimate of the channel delay. The protocol does not require a base station and keeps no TCP state. TULIP is exceptionally robust when bit error rates are high; it maintains high goodput, i.e., only those packets which are in fact dropped on the wireless link are retransmitted and then only when necessary. The performance of TULIP is compared against the performance of the Snoop protocol (a TCP-aware approach) and TCP without link-level retransmission support. The results of simulation experiments using the actual code of the Snoop protocol show that TULIP achieves higher throughput, lower packet delay, and smaller delay variance.
Growth characteristics and influencing factors of 3D hierarchical flower-like SnS2 nanostructures and their superior lithium-ion intercalation performance

Abstract 3D hierarchical SnS2 nanoflowers are prepared by a template-free, inexpensive and controllable approach for their application to Li-ion batteries. They are composed of intertwining twisted nanosheets as the building unit. Their formation mechanism is explored through a group of time-dependent experiments. It is for the first time found that the morphological evolution, phase transition and composition changes occur simultaneously during their growth process. Three influencing factors, namely precursor concentration, reaction temperature and time, are examined by the observation of SnS2 nanostructures, to achieve the controlled synthesis of high-quality 3D SnS2 hierarchitectures. Irregular SnS2 nanoparticles are produced for a comparison with the SnS2 nanoflowers in terms of Li-ion insertion properties. The former shows smaller capacities and poorer rate capability than the latter. In tests the former exhibits capacities of 249.5–404.5 mA h g−1 at 100 mA g−1 over 50 battery cycles, while the latter could deliver capacities of 432–519 mA h g−1. In addition, the former displays capacities of 372 to 105 mA h g−1 while the latter shows capacities of 498 to 297 mA h g−1 as the current arises from 100 to 800 mA g−1. Redox reaction characteristics and Li-ion transfer kinetics at the two SnS2 anodes are studied with differential capacity curves and electrochemical impedance spectroscopy. It is concluded that the excellent electrochemical behaviors of SnS2 nanoflowers derive from their structural merits such as large surface area, hierarchical porous structure and sheet-like building units that endow them with improved electrode reactions and charge transfer kinetics.
Using imputed pre-treatment cholesterol in a propensity score model to reduce confounding by indication: results from the multi-ethnic study of atherosclerosis

Studying the effects of medications on endpoints in an observational setting is an important yet challenging problem due to confounding by indication. The purpose of this study is to describe methodology for estimating such effects while including prevalent medication users. These techniques are illustrated in models relating statin use to cardiovascular disease (CVD) in a large multi-ethnic cohort study. The Multi-Ethnic Study of Atherosclerosis (MESA) includes 6814 participants aged 45-84 years free of CVD. Confounding by indication was mitigated using a two step approach: First, the untreated values of cholesterol were treated as missing data and the values imputed as a function of the observed treated value, dose and type of medication, and participant characteristics. Second, we construct a propensity-score modeling the probability of medication initiation as a function of measured covariates and estimated pre-treatment cholesterol value. The effect of statins on CVD endpoints were assessed using weighted Cox proportional hazard models using inverse probability weights based on the propensity score. Based on a meta-analysis of randomized controlled trials (RCT) statins are associated with a reduced risk of CVD (relative risk ratio = 0.73, 95% CI: 0.70, 0.77). In an unweighted Cox model adjusting for traditional risk factors we observed little association of statins with CVD (hazard ratio (HR) = 0.97, 95% CI: 0.60, 1.59). Using weights based on a propensity model for statins that did not include the estimated pre-treatment cholesterol we observed a slight protective association (HR = 0.92, 95% CI: 0.54-1.57). Results were similar using a new-user design where prevalent users of statins are excluded (HR = 0.91, 95% CI: 0.45-1.80). Using weights based on a propensity model with estimated pre-treatment cholesterol the effects of statins (HR = 0.74, 95% CI: 0.38, 1.42) were consistent with the RCT literature. The imputation of pre-treated cholesterol levels for participants on medication at baseline in conjunction with a propensity score yielded estimates that were consistent with the RCT literature. These techniques could be useful in any example where inclusion of participants exposed at baseline in the analysis is desirable, and reasonable estimates of pre-exposure biomarker values can be estimated.
Thermodynamics and interfacial tension of multicomponent liquid‐liquid interfaces

Sternling and Scriven have shown that the derivative of interfacial tension with respect to solute concentration is an important parameter influencing the hydrodynamic stability at an interface across which mass transfer is taking place. This work is concerned with a molecular thermodynamic study of that derivative. With surface thermodynamics and an extension of the solution theory of Schuchowitzky, an expression is derived which relates the interfacial tension to the solute concentration in terms of physically meaningful parameters. These in turn are related to molecular properties of the solute and solvent species. New experimental data are reported for the interfacial tension of nine ternary systems; these consist of an aqueous phase and an organic phase where both phases are dilute solutions of an alcohol. The organic phases are hexane, benzene, and carbon tetrachloride and the alcohols are methanol, ethanol, and n-propanol. The theoretical equations predict interfacial tensions which are in good agreement with the new experimental results and with experimental data of Vignes on aqueous-organic systems which are dilute solutions of organic acids.
Computer-assisted oral and intravenous theophylline therapy.

Abstract An interactive computer program was developed to assist clinicians in selecting appropriate intravenous and oral theophylline dosages. The program uses an iterative method to estimate pharmacokinetic parameters. This method was compared to methods previously described. Results of a clinical evaluation of the program suggest that the iterative computer program can substantially reduce the prediction error inherent in other methods of estimating theophylline requirements.
PULSE-SHAPING IN SHORT-PULSE FEL OSCILLATORS USING MULTIPLE RESONATORS

Abstract A novel method is proposed for the efficient production of optical pulses that are shorter than a slippage length. The concept uses short electron bunches and a multiple cavity FEL oscillator configuration.
Biostructural chemistry of magnesium. Regulation of mithramycin-DNA interactions by Mg2+ coordination

Abstract Divalent magnesium promotes the selective binding of mithramycin to a cognate DNA sequence (5′-XXGCXX-3′) by a coupled mechanism requiring local conformational changes in the polynucleotide backbone and a structural rearrangement of the mithramycin dimer. Circular dichroism, 31 P-NMR, and analysis of the topological change of supercoiled plasmid DNA by agarose gel electrophoresis support these conclusions and offer insight on the regulatory role of Mg 2+ . Molecular modeling suggests that sequence selectivity arises from preferential coordination of Mg 2+ to d(GpC) domains in the minor groove of Z-type DNA. We suggest a specific structural role for the essential divalent magnesium ion, and propose a revision of the binding mechanism previously devised for the mithramycin/DNA complex. This revised structural model is entirely consistent with NMR results reported for the mithramycin and related chromomycin complexes, but previously interpreted in terms of an A-type configuration.
Who Won the Winter 2010 Olympics?: A Quest into Priorities and Rankings

During and at the end of Olympic games, we are always given the number of gold, silver and bronze medals won by each country and often the total number won as an indicator of the surmised winner. The groups that report the medal count in this manner indicate that they believe all medals are the same, regardless of the kind of medal involved. Perhaps one reason it is done this way is because there has not been a scientific way to assign appropriate weights to each type of medal. This paper explores use of the measurement theory, the Analytic Hierarchy Process (AHP), to quantify the values of gold, silver and bronze medals and use these values to compute the total value of the medals won by the leading countries in order to determine which country may be considered the winner of the 21st Winter Olympics held February 12–28, 2010, in Vancouver, Canada. Copyright © 2010 John Wiley & Sons, Ltd.
The Role of Public Input in State Welfare Policymaking

This article reports findings from a survey of 257 state officials involved in public assistance policymaking in the American states during the early to mid-1990s. Respondents were asked to comment on the impetus for welfare reform, on methods employed to gauge public preferences, and on sources of policy ideas. These officials, including state legislators, social service agency directors, and senior advisors to governors, revealed a variety of forums for gathering public input. Although few respondents affiliated with elective office reported significant direct electoral challenges on welfare issues, they often cited constituent contacts regarding welfare reform.
Collective excitations in a linear periodic array of cylindrical nanotubes

A theory of collective plasma excitations in a linear periodic array of multishell nanotubes is presented. The electron system in the nanotubes is modeled by a quasifree electron gas confined to the surface of an infinitely long cylinder. The plasmon dispersion equation is derived in the random-phase approximation neglecting the electron tunneling between the individual cylindrical tubules. The dispersion equation is solved numerically for a single-wall nanotube array, and the plasmon excitation energies are obtained as a function of the wave vector in the direction of the nanotube axes and in the transverse direction. It is found that the intertube Coulomb interaction couples the modes with different angular momenta m in individual nanotubes and, in particular, lifts the $\ifmmode\pm\else\textpm\fi{}m$ degeneracy of the single-nanotube modes. This effect is analyzed numerically as a function of the separation between the tubules. We show that the translational symmetry of the lattice is maintained in the plasmon spectrum, and the plasmon energies have a periodic dependence on the transverse wave vector.
Specialist practice and the professional project for nursing

This article examines the implications of the UKCC's (1994) decision to determine a sphere of practice for specialist practitioners. It coincides with the move towards professional status within nursing. It is argued that a specialization strategy for nursing has obvious advantages for those who wish nursing to be successful in its professionalization. However, unless managers use long-term planning the potential of specialist nursing practice may not be realized. It is suggested that the professionalization of nursing (professional project) is strongly linked to the fact that nursing remains a predominately female occupation (Witz, 1992), and initiatives, such as specialization, should be viewed from this standpoint. Clinical leadership is crucial to the success of specialism within nursing over the next few years. Opportunities need to be taken to reappraise specialist practitioner roles, and allow innovation to occur. Financial and educational support needs to be available and responsive; the clearer t...
Intravitreal Bevacizumab for Macular Edema Due to Central Retinal Vein Occlusion: Perfused vs. Ischemic and Early vs. Late Treatment

Purpose/aims: This study investigates the efficacy of intravitreal bevacizumab (IVB) for cystoid macular edema (CME) secondary to central retinal vein occlusion (CRVO). Subgroup analysis was performed comparing early (within 90 days of CRVO onset) and late treatment (after 90 days) as well as perfused and ischemic subgroups.Materials and Methods: Retrospective review of 48 consecutive eyes with CRVO treated with IVB was performed. Data collected at various time points included best corrected visual acuity (BCVA), central foveal thickness (FT) on optical coherence tomography (OCT), perfusion status on fluorescein angiography (FA), and complications.Results Mean initial BCVA was 20/288 compared to 20/214 at 12 months (p = 0.07) and 20/204 (p = 0.03) at final follow-up. Initial mean central FT was 591 micrometers compared to 339 micrometers at 12 months (p = 0.003). Mean follow-up was 10.5 months, and mean number of injections was 3.7. After IVB, no significant difference in BCVA gain or edema resolution on ...
A generalized theorem of corresponding states for the thermodynamic properties of nonpolar and polar fluids

Abstract Generalized procedures are discussed for the accurate calculation of thermodynamic properties of nonpolar and polar fluids and mixtures. It is shown that the concepts of van der Waals for simple fluids can be extended to complex substances, and that the properties of a wide range of fluids can be calculated from a sufficient number of macroscopic parameters defined through the vapor pressure. Relationships are presented for the calculation of interaction virial coefficients of binary mixtures from the macroscopic parameters of the pure components. A generalized version of the van der Waals relationships for effective parameters of simple mixtures is developed for complex systems through the composition and temperature dependence of the second virial coefficient. The relationships for effective parameters enable the calculation of the thermodynamic properties of a mixture, including phase behavior, from the parameters of the pure components, without the requirement of experimental data for the specific system.
Valvular Heart Disease: Classic Teaching and Emerging Paradigms

Valvular heart disease is both prevalent and increases with age. The final pathway of valvular disease is heart failure and sometimes sudden death, so clinicians must identify and treat it before these endpoints occur. Noninvasive diagnostic modalities such as echocardiography, exercise tolerance testing, and cardiac magnetic resonance provide additional quantitative, qualitative, and prognostic data. Studies have elucidated predictors of disease progression and potential medical therapies, but the niche of valvular disease has benefited relatively less from randomized controlled clinical trials than other cardiovascular disease fields. New invasive techniques like transcatheter valve replacement offer hope for high-risk operative candidates. We review classic teaching with current guidelines and emphasize recent advances in disease management.
Pharmacological characterization of P2Y receptor subtypes on isolated tiger salamander Müller cells.

Muller cells express a variety of neurotransmitter receptors that permit them to sensethe extracellular environment within the retina. We have used a battery of agonists and antagonists to characterize the purinergic receptor subtypes expressed on isolated tiger salamander Muller cells. Changes in intracellular calcium ion concentration ([Ca 2+ ] i ) in Muller cells were measured using the Ca 2+ indicator dye Fura-2 and digital imaging microscopy. ATP, 2-methylthio-ATP, 2-methylthio-ADP, ADP, UTP, UDP, deoxyATP, and 3'-O-(4-benzoyl)benzoyl ATP evoked increases in [Ca 2+ ] i in both the presence and absence of extracellular Ca 2+ Therefore, the increases we observed were likely due to intracellular Ca 2+ release mediated by G-protein-coupled P2Y receptor activation, rather than Ca 2+ influx via P2X receptor channels. The P2Y 1 receptor agonists 2-methylthio-ATP, 2-methylthio-ADP, and ADP evoked increases in [Ca 2+ ] i that were inhibited by the P2Y 1 receptor antagonists adenosine 3'-phosphate 5'-phosphosulfate and 2'-deoxy-N6-methyleneadenosine-3',5'-bisphosphate. Responses to ADP were not completely inhibited by the P2Y 1 receptor antagonists. The residual response to ADP could be mediated by P2Y 13 receptors. UTP evoked an increase in [Ca 2+ ] i that was partially inhibited by suramin, suggesting that Muller cells express P2Y 2 and P2Y 4 receptors. The P2Y 6 receptor agonist UDP, and the P2Y 11 receptor agonists deoxyATP, and 3'-O-(4-benzoyl)benzoyl ATP, evoked increases in [Ca 2+ ] i in Muller cells. We conclude that isolated tiger salamander Muller cells express P2Y 1 , P2Y 2 , P2Y 6 , P2Y 11 , and possibly P2Y 4 and P2Y 13 receptors. Therefore, the physiological release of ATP, ADP, UTP, and UDP and/or their accumulation in the retina under pathological conditions could stimulate increases in [Ca 2+ ] i in Muller cells. GLIA 42:149-159, 2003.
Compensation of oculomotor deficits in monkeys with neonatal cerebellar ablations.

The oculomotor performance of 11 monkeys, who had various degrees of cerebellar ablation shortly after birth, is described in this study. Detailed numerical results were obtained on three of these adult macaques after extensive training of specific pursuit eye movements and fixation. The vestibular nuclei were kept intact. (1) In the presence of the intracerebellar nuclei, quite extensive neonatal ablations of the cerebellar cortex leave the adult monkey without any discernable oculomotor deficits. (2) If ablation also includes the nuclei on one side, compensation is never complete even several years later: while vestibulo-ocular and saccadic responses seem normal, there are deficits in pursuit and gaze holding performance. The residual deficits vary with the extent of the ablation and are comparable with the pattern exhibited by acute hemicerebellar ablations. (3) Monkeys who had their cerebellum including the nuclei essentially completely removed just after birth, could pursue, albeit with limited velocity, and hold gaze, albeit in a limited zone. Their vestibuloocular responses seemed unaffected.
The perils of conducting meta-analyses of observational data.

Dear Editors, We read with interest Li and colleagues’ recent article in this journal, which conducted a systematic review and meta-analysis of the literature on associations between intimate partner violence (IPV) and HIV infection in women. The authors found a significant positive association between various types of IPV and HIV, concluding that “physical violence, sexual violence, a combination of physical and sexual violence, and any type of IPV were associated with HIV infection in women (p. 7)”. (Published: 9 June 2014) Citation: Harling G and Subramanian SV. Journal of the International AIDS Society 2014, 17 :19112 http://www.jiasociety.org/index.php/jias/article/view/19112 | http://dx.doi.org/10.7448/IAS.17.1.19112
On being the right scale: sizing large collections of 3D models

We address the problem of recovering reliable sizes for a collection of models defined using scales with unknown correspondence to physical units. Our algorithmic approach provides absolute size estimates for 3D models by combining category-based size priors and size observations from 3D scenes. Our approach handles un-observed 3D models without any user intervention. It also scales to large public 3D model databases and is appropriate for handling the open-world problem of rapidly expanding collections of 3D models. We use two datasets from online 3D model repositories to evaluate against both human judgments of size and ground truth physical sizes of 3D models, and find that an algorithmic approach can predict sizes more accurately than people.
Metallothionein-I-Transgenic Mice Are Not Protected from Acute Cadmium–Metallothionein-Induced Nephrotoxicity

Mice pretreated with Zn have increased renal metallothionein (MT) levels and are protected from CdMT nephrotoxicity. To determine whether MT is important in this Zn-induced protection against CdMT-induced nephrotoxicity, MT-transgenic mice that have high levels of MT in their kidneys (10-fold over control mice) have been studied to determine whether they are resistant to CdMT-induced nephrotoxicity. Mice were injected with CdMT (0.1-0.6 mg Cd/kg, iv) and kidney injury was evaluated 24 hr later. CdMT produced renal toxicity in a dose-dependent manner. At a nephrotoxic dose of CdMT (0.4 mg Cd/kg), urinary protein and glucose excretion were increased 30- and 60-fold, respectively, in control mice. However, similar increases in protein and glucose excretion were also observed in MT-transgenic mice. CdMT also induced a similar dose-dependent proximal tubular cell necrosis in both control and MT-transgenic mice in a dose-dependent manner. Treatment of control mice with Zn (100 micromol/kg, sc x 2 days) increased renal MT to levels similar to those of untreated MT-transgenic mice and protected against CdMT-induced renal injury. Furthermore, when Zn (25-100 micromol/kg, sc) was given immediately before CdMT injection (i.e., without preinduction of MT), it was still effective in preventing CdMT nephrotoxicity. We conclude that Zn-induced protection against CdMT nephrotoxicity does not appear to be due to induction of renal MT.
Phase-Locked-Loop Adaptive-Optic Controller and Simulated Shear Layer Correction

An alternative adaptive-optic controller, using both flow control and a phase-lock-loop control strategy, has been designed to overcome bandwidth limitations inhibiting current adaptive-optic controllers. A discrete-vortex code and weakly compressible model were used to simulate high-speed shear layer adaptive-optic corrections based upon the proposed phase-lock-loop controller given a range of upper and lower Mach numbers. The shear layer was forced at its origin, creating a region of regularized large-scale structures through which a simulated optical beam was projected. The controller applied a predicted conjugate correction to the shear layer’s emerging wavefront in a feedforward approach. The phase-lock-loop controller produces a sinusoidal signal for which the amplitude and phase are adjusted in real time to synchronize with the reference input. The controller is designed to track abrupt changes in phase or frequency. An overview of the design process is provided along with the alternative adaptive-...
Microcrack nucleation and fracture in silver crystals

Abstract Single crystal silver ribbons were strained to fracture with a precision tensile stage inside of a high voltage electron microscope. Direct observations of the dynamical fracture processes have permitted a detailed microstructural analysis of the basic ductile fracture mechanisms involved. Specimens were found to undergo extensive necking during elongation which resulted in lattice rotation and tensile axis reorientation. Cracks initiated at one of the edges of the specimens in the necked zone and propagated through the specimens at an angle of 60° to the tensile axis. The mechanism of crack propagation was one of the formation of microcracks directly in front of the macrocrack. A highly significant feature of the nucleation and development of the microcracks was their cristallographie nature, and subsequent development into crystallographic holes bordered by 〈110〉 directions. The formation of the macrocrack was completed by the coalescence of the crystallographic holes. Characteristic fracture behavior appeared to be independent of specimen thickness and representative of bulk fracture behavior. A detailed analysis of the observed processes has provided the foundation for a mechanism for the fracture of crystals that is based on the general principles of glide and dislocation behavior.