cssi/SciSciGPT-SciSciNet huggingface dataset:
A Toxoplasma Prolyl Hydroxylase Mediates Oxygen Stress Responses by Regulating Translation Elongation.

ABSTRACT As the protozoan parasite Toxoplasma gondii disseminates through its host, it responds to environmental changes by altering its gene expression, metabolism, and other processes. Oxygen is one variable environmental factor, and properly adapting to changes in oxygen levels is critical to prevent the accumulation of reactive oxygen species and other cytotoxic factors. Thus, oxygen-sensing proteins are important, and among these, 2-oxoglutarate-dependent prolyl hydroxylases are highly conserved throughout evolution. Toxoplasma expresses two such enzymes, TgPHYa, which regulates the SCF-ubiquitin ligase complex, and TgPHYb. To characterize TgPHYb, we created a Toxoplasma strain that conditionally expresses TgPHYb and report that TgPHYb is required for optimal parasite growth under normal growth conditions. However, exposing TgPHYb-depleted parasites to extracellular stress leads to severe decreases in parasite invasion, which is likely due to decreased abundance of parasite adhesins. Adhesin protein abundance is reduced in TgPHYb-depleted parasites as a result of inactivation of the protein synthesis elongation factor eEF2 that is accompanied by decreased rates of translational elongation. In contrast to most other oxygen-sensing proteins that mediate cellular responses to low O2, TgPHYb is specifically required for parasite growth and protein synthesis at high, but not low, O2 tensions as well as resistance to reactive oxygen species. In vivo, reduced TgPHYb expression leads to lower parasite burdens in oxygen-rich tissues. Taken together, these data identify TgPHYb as a sensor of high O2 levels, in contrast to TgPHYa, which supports the parasite at low O2. IMPORTANCE Because oxygen plays a key role in the growth of many organisms, cells must know how much oxygen is available. O2-sensing proteins are therefore critical cellular factors, and prolyl hydroxylases are the best-studied type of O2-sensing proteins. In general, prolyl hydroxylases trigger cellular responses to decreased oxygen availability. But, how does a cell react to high levels of oxygen? Using the protozoan parasite Toxoplasma gondii, we discovered a prolyl hydroxylase that allows the parasite to grow at elevated oxygen levels and does so by regulating protein synthesis. Loss of this enzyme also reduces parasite burden in oxygen-rich tissues, indicating that sensing both high and low levels of oxygen impacts the growth and physiology of Toxoplasma.
Environmental controls on shallow subtidal molluscan death assemblages on San Salvador Island, The Bahamas

Abstract Ecological studies that span multiple marine depositional environments frequently find that benthic invertebrate assemblages are correlated primarily with an onshore-offshore gradient. Variability within the same depositional environment is inferred to not result from water depth differences, but other parameters such as substrate consistency and shear stress. Modern studies focusing on assemblage variations within the same depositional environment can identify which variables affecting assemblage compositions are independent of water depth. This study examines the environmental controls on the composition of molluscan death assemblages from the shallow subtidal environments of San Salvador Island. Molluscan assemblages were tabulated from twenty-nine bulk samples collected from four locations around San Salvador Island representing seagrass meadows, open sandflats, and patch reef systems common in the shallow subtidal. In addition, quantitative environmental data for each sample was characterized, including seagrass density, water depth, temperature, pH, dissolved oxygen, and grain-size, as well as qualitative observations of wave energy and bioturbation. Cluster analysis and canonical correspondence analysis (CCA) were performed to identify environmental gradients associated with molluscan assemblage composition. Cluster analysis and CCA Axis 1 identify seagrass coverage and substrate consistency as the primary environmental variables describing molluscan death assemblage compositions. CCA Axis 2 identifies wave energy, bioturbation, and dissolved oxygen as the secondary environmental variables, though the small range of dissolved oxygen values (17–21 mg/L) collected using single, instantaneous measurements make it unclear whether the oxygen gradient is ecologically significant for our time-averaged assemblages. Our analysis demonstrates the variability of assemblages within a single depositional environment, as well as the utility of fine-resolution studies for identifying secondary environmental variables that control the composition of marine invertebrate assemblages.
A Microglia Sublineage Protects from Sex-Linked Anxiety Symptoms and Obsessive Compulsion

Aberrant microglia activity is associated with many neurological and psychiatric disorders, yet our knowledge about the pathological mechanisms is incomplete. Here, we describe a genetically defined microglia sublineage in mice which has the ability to suppress obsessive compulsion and anxiety symptoms. These microglia derive from precursors expressing the transcription factor Hoxb8. Selective ablation of Hoxb8-lineage microglia or the Hoxb8 gene revealed that dysfunction in this cell type causes severe over-grooming and anxiety-like behavior and stress responses. Moreover, we show that the severity of the pathology is set by female sex hormones. Together, our findings reveal that different microglia lineages have distinct functions. In addition, our data suggest a mechanistic link between biological sex and genetics, two major risk factors for developing anxiety and related disorders in humans.
Social Anxiety and Perceived Social Support: Gender Differences and the Mediating Role of Communication Styles.

Social anxiety has been linked with lower perceived social support, and there is some evidence that communication styles may explain this relationship. In addition, a body of literature has found g...
Water use and electricity-for-water savings trends in three representative U.S. cities

A life-cycle assessment approach is used to analyze the energy demand and greenhouse gas emissions associated with potable water usage trends in three major cities of the United States in different regions and climates and relying on different types of raw water sources. Between 2011 and 2016, a decreasing trend in per-person water consumption is observed despite growing populations. The per-person water consumption decreased by 10% in Tucson (Arizona) and Washington, DC, and by 16% in Denver (Colorado). Leveraging certain distinctive water and electricity supply characteristics of the case study cities can provide insights into potential interventions and cross-comparison for generalizing trends. In Tucson, potable water production is the most energy intensive and electricity is produced mainly from coal. The greenhouse gas emissions of the per-person water consumption in Tucson are about five times higher compared to Denver and Washington, DC, thus water savings in Tucson should be particularly pursued. GHG emissions decreased in the period by even higher percentages than water use: 15%, 14% and 27% between 2011 and 2016 for Tucson, Washington, DC, and Denver, respectively. In 2015, just four years' worth of forgone GHG emissions in Tucson were somewhat higher than the total GHG emissions associated with water consumption in all of Washington, DC, a city with the same population size as Tucson. Results show that cities should prioritize promotion of water savings to decrease the average per-person water consumption because it can be achieved and can compensate for increases in population. Lower greenhouse gas emissions can be attained in tandem with the local electric power industry.
Bubble Coalescence at Wormlike Micellar Solution-Air Interfaces.

Surfactants in aqueous solutions self-assemble in the presence of salt, to form long, flexible, wormlike micelles (WLM). WLM solutions exhibit viscoelastic properties and are used in many applicati...
Assessment of Uterine Anatomy and Implications of Müllerian Disorders and Acquired Uterine Lesions on Fertility

Uterine factor infertility is a relatively uncommon cause of female infertility occurring in <5% of women. Multiple uterine factors have been implicated in reproductive failure (due to infertility or recurrent pregnancy loss) including congenital disorders and acquired lesions. A thorough evaluation and treatment of all other causes of infertility must be undertaken even when uterine factors are diagnosed.
Lessons Learned in Implementing VA Video Connect for Evidence-Based Psychotherapies for Anxiety and Depression in the Veterans Healthcare Administration.

A top priority for the Veteran's Healthcare Administration is improving access to high-quality mental healthcare. Mobile and telemental healthcare are a vital component of increasing access for veterans. The Veteran's Healthcare Administration is making efforts to further broaden how veterans receive their care through VA Video Connect, which allows veterans to connect with their provider from their residence or workplace. In this mixed-methods study, successes and challenges associated with the rapid implementation of VA Video Connect telemental health appointments are examined through (1) administrative data and (2) qualitative interviews at one medical center. Within 1 year of the telehealth initiative, the number of providers experienced with telemental health increased from 15% to 85%, and telehealth appointments increased from 5376 to 14,210. Provider reported barriers included administrative challenges and concerns regarding care. Having an implementation model of telehealth champions and a team of experienced mental health providers allowed for rapid adoption of telehealth. Utilizing a similar model in other settings will further enable more veterans with depression and anxiety to have access to evidence-based psychotherapy, regardless of location or national crisis. With the dramatic increase in both training for providers as well as veteran use of telemental healthcare during the COVID-19 pandemic response, future research should aim to better understand which teams were able to switch to telehealth easily versus those which struggled, along with examining system-wide and provider-level factors that facilitated continued use of telehealth after social distancing requirements related to COVID-19 were relaxed.
Global Dynamics of the Oregonator System

In this work, the existence and properties of a global attractor for the solution semiflow of the Oregonator system are proved. The Oregonator system is the mathematical model of the celebrated Belousov–Zhabotinskii reaction. A rescaling and grouping estimation method is developed to show the absorbing property and the asymptotic compactness of the solution trajectories of this three-component reaction–diffusion system with quadratic nonlinearity. It is also proved that the fractal dimension of the global attractor is finite and an exponential attractor exists for the Oregonator semiflow. Copyright © 2012 John Wiley & Sons, Ltd.
Protecting the Boundaries: Unclaimed Consideration in the Patentee's Social Contract

This article argues that the primary value society receives in the patentee’s social contract is not new inventions, but “unclaimed consideration.” Unclaimed consideration takes many forms: additional innovations to improve on the patented invention; additional innovations created through efforts to design around the patented invention; innovations created by losers in the patent race; innovations informed by the unclaimed technical information in patents; commercialization of the patented invention or these other innovations; and the signals that patents give to investors regarding the value of a company or research lab. This unclaimed consideration is not necessarily a positive externality or “spillover,” because the inventor herself may well capture the value of the unclaimed consideration. And while there are many schools of patent scholarship engaged in spirited debate regarding how patents serve (or fail to serve) society, this article is the first to recognize and map the growing consensus among modern patent theories that this unclaimed consideration is of primary value and importance to society. Indeed the majority of claimed inventions are never commercialized or licensed, and so granting the patent monopoly in most cases can only be justified by society receiving some other form of consideration. The courts should therefore guard the boundaries of patent claims to avoid the perverse result of allowing the thicket of claimed inventions to stifle the development of unclaimed consideration. The article demonstrates this point through a case study of Siemens Medical Solutions v. Saint-Gobain Ceramics & Plastics, in which the Federal Circuit decided that an accused product can equivalently infringe a patent even after it is declared by the Patent and Trademark Office to be separately patentable and non-obvious over the asserted patent. The majority of a sharply divided court thereby allowed a broad doctrine of equivalents to ensnare unclaimed consideration, relying on reasoning myopically wed to the belief that the sole way in which the patent laws promote progress is by incentivizing claimed inventions. The courts should instead lean on the side of protecting unclaimed consideration, which modern patent theory recognizes is the substantial return society ought to receive in return for the patent grant.
Impact Damage Of Long Plastic Cylinders

The objective of the paper is to assess the local damage of long tubular members and pipes caused by the impact of a rigid mass. The formulation is general and covers a wide range of events: low velocity-large mass impacts, as encountered in collisions; medium velocity impacts caused by dropped objects; and projectile and missile impacts. By making assumptions on the cross-sectional deformed shape of the cylinder, the two-dimensional shell problem was reduced to a one-dimensional problem of a plastic string resting on a rigid-plastic foundation. It was shown that the deformation propagates away from the point of disturbance with a constant plastic wave speed and diminishing amplitude. The instantaneous velocity and deflection profiles, the final deformed shape of the shell, and the maximum deflection attainable under impact were calculated. A parametric study was performed by changing the mass and velocity of the impacting object over several order of magnitude. An approximation to the dynamic solution was also obtained by using the static solution of the shell under "knife" loading and comparing the plastic work of the deformation process to the kinetic energy of the impacting mass. The approximation was compared to the dynamic solution and good agreement was shown for a range of masses and impact velocities encountered in offshore applications. Finally, use of the proposed methodology was illustrated by predicting the local damage caused by a frill-collar accidentally falling on one of the brace tubular members of an offshore platform.
Isotropic Stochastic Flows: A Survey

This article is intended to be a pedagogical survey of some of the results on isotropic stochastic flows obtained during the last decade by Baxendale, Harris, Le Jan, Matsumoto, and the author; the omission of any other work on this subject is solely due to ignorance, and information from readers is much appreciated. It is neither intended to be balanced nor complete, and proofs which appear elsewhere will be omitted; however outlines of proofs will be given for new results.
Byzantine agreement with a minimum number of messages both in the faultless and worst case

A known lower bound for the number of messages in the worst case for all synchronous authenticated Byzantine agreement protocols (BAPs) for any t < m is /spl Omega/(m + t/sup 2/). A BAP is given for any t < m which achieves this bound and minimizes the number of messages for the faultless case to m-1. This shows that minimizing the number of messages in the faultless ase can be achieved without an additional amount of messages. If the faultless case is the usual case, a high number of messages will no longer be a counterargument against the employment of BAPs in practice.
Chiroptical Properties of Amino Compounds

1 Introduction 2 Asymmetric Synthesis 3 Estimation of Enantiomeric Excess 4 Electronic Circular Dichroism (ECD) 5 Vibrational Optical Activity (VOA) Keywords: chiroptical properties of amino compounds; asymmetric synthesis - synthesis using enzymes; alkene aziridination with chiral diimine-based catalysts; enantiomeric excess estimation; chromatography using chiral stationary phases; electronic circular dichroism (ECD); enzyme-catalyzed stereoselective synthesis of propanolamine enantiomers; amino group effect on benzene chromophore
Inhibition of erythropoietin production in unanesthetized rabbits exposed to an acute hypoxic-hypercapnic environment.

Major factors affecting changes in the arterial Hb--O/sub 2/ affinity (P/sub 50/) were examined in relation to the initiation of erythropoietin (ESF) production in unanesthetized New Zealand white male rabbits. They were exposed to an isobaric hypoxic environment (8.8% O/sub 2/) with and without CO/sub 2/ (5.6% or 10%). During 5 hr exposure samples of arterial blood were collected for measurements of (1) plasma ESF titers, (2) whole blood pH, P/sub O/sub 2//, P/sub CO/sub 2//, S/sub O/sub 2//, lactate, pyruvate, and P/sub 50/, and (3) intraerythrocytic 2,3--DPG, ATP, and ADP. Exposure to 8.8% O/sub 2/ alone stimulated ESF production and caused a leftward shift in the P/sub 50/ in vivo (P/sub 50(i.v.)/); the addition of CO/sub 2/ significantly inhibited ESF production and blocked the shift in P/sub 50(i.v.)/. The shifts in P/sub 50(i.v.)/ generally followed changes in pH; possibly a lesser influence was exerted by changes in the ADP concentration. The data suggest that increased oxygenation of the whole-body tissues occurs with exposure to 8.8% O/sub 2/ + CO/sub 2/, as reflected by lower whole-blood excess lactate accumulation. We conclude that the suppression of ESF production is a result of this increased oxygenation. Increased tissue oxygenation with the hypoxic-hypercapnicmore » exposures is probably the result of increased pulmonary ventilation coupled with facilitated oxygen unloading to the tissues as a result of a relatively right-shifted P/sub 50(i.v.)/.« less
Storage Estimation for Multidimensional Aggregates in the Presence of Hierarchies

To speed up multidimensional data analysis, database systems frequently precompute aggregates on some subsets of dimensions and their corresponding hierarchies. This improves query response time. However, the decision of what and how much to precompute is a difficult one. It is further complicated by the fact that precomputation in the presence of hierarchies can result in an unintuitively large increase in the amount of storage required by the database. Hence, it is interesting and useful to estimate the storage blowup that will result from a proposed set of precomputations without actually computing them. We propose three strategies for this problem: one based on sampling, one based on mathematical approximation, and one based on probabilistic counting. We investigate the accuracy of these algorithms in estimating the blowup for different data distributions and database schemas. The algorithm based upon probabilistic counting is particularly attractive, since it estimates the storage blowup to within provable error bounds while performing only a single scan of the data. *Work supported by an IBM CAS Fellowship, NSF grant IRI9157357, and a grant from IBM under the University Partnership Program. Permission to copy without fee all or part of this material is granted provided that the copies are not made or distributed for direct commercial advantage, the VLDB copyright notice and the title of the publication and its date appear, and notice is given that copying 1:s by permission of the Very Large Data Base Endowm.ent. To copy otherwise, 01‘ to republish, requires a fee and/or special permission j~orn the En.do?ument. Proceedings of the 22nd VLDB Conference Mumbai(Bombay), India, 1996
Signaling by the cytokine receptor superfamily in normal and transformed hematopoietic cells.

Publisher Summary This chapter focuses on the structure and function of the cytokine receptor superfamily and the alterations in function that have been associated with leukemias. The malignant transformation of hematopoietic cells is associated with alterations in specific phenotypic properties of the cells. These alterations can involve changes in the ability of the cells to terminally differentiate, the increased rates of cell cycle progression, the reduction or elimination of apoptosis, and the abrogation of the requirements for normal growth factors. Hematopoiesis is normally controlled, in part, through the regulated availability of a variety of hematopoietic growth factors. The majority of hematopoietic growth factors utilizes a novel family of receptors termed the “cytokine receptor superfamily”. The cytokine receptor superfamily was initially identified by comparison of the structure of the first hematopoietic growth factor receptors that were cloned. Growth-factor independence in leukemias can be conferred by the activation of growth-factor production in an autocrine model of transformation. Vav was initially identified as a novel human gene whose transforming activity was activated by a vector insertion in transfection studies to identify new human oncogenes. In addition to tyrosine kinases, protein tyrosine phosphatases play a critical role in cytokine signaling. Studies dealing with the biochemical events in interferon (IFN)-induced gene transcription identified a novel family of transcriptional factors. Although Statl and Stat2 were initially identified and characterized within the context of the interferon system, a variety of studies support the hypothesis that Stat family members may play a very general role in cytokine signaling. The diversity of Stats that can be activated in response to cytokines is illustrated by the responses of T cells.
The Housing-Asset Relief Program: A Plan for Stabilizing the Housing and Securities Markets

As many as six million U.S. homeowners are facing foreclosure during 2009 and beyond. Delinquent residential mortgages are at the heart of the ongoing financial crisis, as they have been packaged into mortgage-related securities originally worth trillions of dollars, but now valued at substantial discounts. I propose to address this crisis by striking at the heart of the problem - by refinancing delinquent mortgages. Approximately $300 billion in TARP or stimulus funds would be used to write down the principal on these mortgages so that new mortgages would meet underwriting guidelines for debt-to-income ratios. Delinquent mortgages would be repaid in the refinancing, eliminating approximately $1.5 trillion in toxic assets from the balance sheets of lenders and the asset pools underlying mortgage-related securities. This proposal is designed to achieve three goals: (1) to enable as many as six million families to avoid eviction and stay in their homes; (2) to recapitalize the banking system; and (3) to detoxify mortgage-related securities by eliminating delinquent mortgages from the underlying pool of assets, thereby avoiding the need for complex “price discovery” plans for pricing these toxic securities. This program deals with a number of practical problems that have dogged other proposals, including how to provide for significant principal reduction, how prevent ruthless defaults by healthy but underwater borrowers, how to deal with second-lien holders, how to deal with mortgages in pools of securitized assets, and how to properly price toxic mortgage-related securities.
Efficient planning by graph rewriting

Planning involves the generation of a network of actions that achieves a desired goal given an initial state of the world. There has been significant progress in the analysis of planning algorithms, particularly in partial-order and in hierarchical task network (HTN) planning. In this abstract we propose a more general framework in which planning is seen as a graph rewriting process. This approach subsumes previous work and offers new opportunities for efficient planning.
Microhelix aminoacylation by a class I tRNA synthetase. Non-conserved base pairs required for specificity

Nucleotides in tRNAs that are conserved among isoacceptors are typically considered as candidates for tRNA synthetase recognition, with less importance attached to non-conserved nucleotides. Although the anticodon is an important contributor to the identity of methionine tRNAs, the class I methionine tRNA synthetase aminoacylates microhelices with high specificity. The microhelix substrates are comprised of as few as the 1st 4 base pairs of the acceptor stems of the elongator and initiator methionine tRNAs. For these two tRNAs, only the central 2:71 and 3:70 base pairs are common to the 1st 4 acceptor stem base pairs. We show here that, although the flanking 4:69 base pair is not conserved, a particular substitution at this position substantially reduces the gel electrophoresis-detected aminoacylation of an acceptor stem substrate that has the conserved 2:71 and 3:70 base pairs. Although the two methionine tRNAs have either U:A or G:C at position 4:69, substitution with C:G reduces charging of 9- or 4-base pair substrates that recreate part or all of the acceptor stem of a methionine tRNA. This effect is sufficient for methionine tRNA synthetase to discriminate between the closely related methionine and isoleucine tRNA acceptor stems. The ability to distinguish G:C and U:A from C:G is contrary to a simple scheme for recognition of atoms in the RNA minor groove.
The use of high-dose azidothymidine in combination with chemotherapy upfront is an effective treatment approach for gamma-herpes virus-related non-Hodgkin’s lymphomas

The use of high-dose azidothymidine in combination with chemotherapy upfront is an effective treatment approach for gamma-herpes virus-related non-Hodgkin’s lymphomas Ulas Darda Bayraktar, Eileen Bernal, Lisa Cabral, William J Harrington Jr., Dirk P Dittmer, Juan Carlos Ramos From 12 International Conference on Malignancies in AIDS and Other Acquired Immunodeficiencies (ICMAOI) Bethesda, MD, USA. 26-27 April, 2010
Piecewise planar surface models from sampled data

Interactive visualization of three dimensional data requires construction of a geometric model for rendering by a graphics processor. We present an automated method for transforming dense, uniformly sampled data grids to an irregular triangular mesh that represents a piecewise planar approximation to the sampled data. The mesh vertices comprise surface-specific points, which characterize important surface features. We obtain surface-specific points by a novel application of linear and non-linear filters, and thresholding. We define a procedure for constructing a triangulation, derived from a Delaunay triangulation, that conforms to the sampled data. In our example application, modeling a terrain surface over a large area, an 80% reduction in polygons maintains an acceptable fit. This method also extends to the tessellation of images. Applications include scientific visualization and construction of virtual environments.
Last Rites for Readability Formulas in Technical Communication

Some reading researchers and technical communicators assume the efficacy of readability formulas. Reading researchers use such formulas to equalize the reading difficulty of texts used in experimen...
Growth failure and altered body composition are established by one month of age in infants with bronchopulmonary dysplasia

Long-term growth failure and altered body composition are common consequences of bronchopulmonary dysplasia (BPD). We hypothesized that these chronic findings are preceded by uncompensated, acute early growth failure. The purpose of this study was to evaluate the effects of developing bronchopulmonary dysplasia on body composition and growth of very-low-birth-weight (VLBW) infants during the first six postnatal weeks. Arm muscle and fat accretion and changes in weight, length and head circumference were evaluated in 16 very-low-birth-weight infants who developed bronchopulmonary dysplasia and compared with 16 birth-weight-matched control infants without bronchopulmonary dysplasia. During the 1st wk, both groups experienced similarly low nutritional intakes, wasting of arm muscle and fat stores, and reduced weight, length and head circumference growth velocities, compared with intrauterine growth standards. Between wk 2 and 4, infants with developing bronchopulmonary dysplasia consumed less protein and energy (P < 0.05), accreted less arm fat and muscle (P < 0.05), and grew more slowly than control infants in all measured variables (P < 0.05). When infants with bronchopulmonary dysplasia had achieved full enteral feedings and had similar protein-energy intakes to control infants, they demonstrated similar rates of growth and arm muscle and fat accretion, but did not demonstrate catch-up growth. These data support the speculation that early reductions in muscle and fat accretion and growth velocity contribute to the long-term growth failure in infants with bronchopulmonary dysplasia. Prevention may require greater attention to defining and delivering optimal nutritional therapy to physiologically unstable premature infants in the immediate postnatal period.
Stencils and Problem Partitionings: Their Influence on the Performance of Multiple Processor Systems

Given a discretization stencil, partitioning the problem domain is an important first step for the efficient solution of partial differential equations on multiple processor systems. We derive partitions that minimize interprocessor communication when the number of processors is known a priori and each domain partition is assigned to a different processor. Our partitioning technique uses the stencil structure to select appropriate partition shapes. For square problem domains, we show that nonstandard partitions (e.g., hexagons) are frequently preferable to the standard square partitions for a variety of commonly used stencils. We conclude with a formalization of the relationship between partition shape, stencil structure, and architecture, allowing selection of optimal partitions for a variety of parallel systems.
(2‐Ethoxy‐1‐propenyl)triphenylphosphonium Iodide

[62639-97-8] C23H24IOP (MW 474.29) InChI = 1S/C23H24OP.HI/c1-3-24-20(2)19-25(21-13-7-4-8-14-21,22-15-9-5-10-16-22)23-17-11-6-12-18-23;/h4-19H,3H2,1-2H3;1H/q+1;/p-1 InChIKey = USVXHKAXMCEZRL-UHFFFAOYSA-M (precursor for 2-ethoxyallylidenetriphenylphosphorane, which is a three-carbon annulation reagent1) Physical Data: mp 163–165 °C. Preparative Methods: by the condensation of Ethyl Iodide with 1-triphenylphosphoranylidene-2-propanone.2 Purification: recrystallization from methanol–ethyl acetate. Handling, Storage, and Precautions: should be dried in vacuo for best results.
From aralu to ORS: Sinhalese perceptions of digestion, diarrhea, and dehydration

Despite Sri Lanka’s relative success in reducing infant mortality and providing primary health care services to the population at large, diarrheal diseases remain a leading cause of morbidity and mortality in the country. In 1979, diarrheal diseases accounted for 45 deaths per 100,000, 53% of all infectious disease deaths in the country. Diarrheal diseases constituted the third leading cause of death for the population at large. Children under 5 years of age account for 49% of all deaths due to diarrheal diseases (Gaminiratne 1984; Pererra 1985; Pollack 1983).1
Boundary detection in skin tumor images: an overall approach and radial search algorithm

Abstract Although computerized boundary detection has been studied in depth, current general algorithms are not highly successful when applied to in vivo medical images where the borders are often not clearly defined and are sometimes difficult even for the human eye to detect. In these cases, domain-specific algorithms are necessary to achieve the required accuracy. This paper addresses the problem of automatic detection of tumor borders in digitized images of skin tumors. The complexity of boundary detection in this domain is such that algorithms based on single boundary determinants such as color, luminance, texture, or three-dimensional information are not capable of correctly identifying the boundary in all cases. Hence, an overall approach is discussed that will use confidence levels to combine results from several border detection algorithms based on the individual criteria mentioned. The development of one such algorithm (using a radial search method on luminance information) and its results are presented. With this approach, problems such as numerous false borders and unknown shape and size of the tumors are overcome.
Deformation potentials for band-to-band tunneling in silicon and germanium from first principles

The deformation potentials for phonon-assisted band-to-band tunneling (BTBT) in silicon and germanium are calculated using a plane-wave density functional theory code. Using hybrid functionals, we obtain: DTA = 4.1 × 108 eV/cm, DTO = 1.2 × 109 eV/cm, and DLO = 2.2 × 109 eV/cm for BTBT in silicon and DTA = 7.8 × 108 eV/cm and DLO = 1.3 × 109 eV/cm for BTBT in germanium. These values agree with experimentally measured values and we explain why in diodes, the TA/TO phonon-assisted BTBT dominates over LO phonon-assisted BTBT despite the larger deformation potential for the latter. We also explain why LO phonon-assisted BTBT can nevertheless dominate in many practical applications.
Limitations of visual assessment of redistribution in thallium images

Potential limitations of visual assessment of redistribution in thallium (Tl) images were studied and results were compared with computer assessment of redistribution. A four-section phantom filled with Tl was imaged (300K counts, 128 × 128 matrix) with appropriate background activity and scatter material. Activity in a “defect” section (DS) was varied from 20% to 100% of reference sections (RS). After interpolative background correction, pseudo “initial” and “late” image pairs (N = 35) were photographed on polaroid film and read by three “blinded” observers using an 0–2, 12 step, scale (0 = absent and 2 = normal activity). Scan defects were detected by all readers when DS activity was ≤59% of RS activity. No reader detected a defect when DS activity was ≥67% of RS activity. All “initial” defects were detected by computer analysis. Visual assessment of “initial” DS:RS activity ratio did not correlate well with DS:RS activity ratio of the phantom. In contrast, computer assessment of “initial” DS:RS activity ratio correlated well with phantom DS:RS activity ratio (r = 0.96, p < .0001). Although 22 of 27 scan pairs with partial (N = 26) or full (N = 1) redistribution were correctly identified as showing redistribution by at least two of three observers, the extent of redistribution was not extimated well by visual analysis. Thus, visual assessment of absolute change (“initial”-to-“late”) in DS:RS activity ratio showed considerable scatter in relations to actual changes in DS:RS activity ratio of the phantom. Furthermore, subtle degrees of redistribution (i.e., absolute increase in DS:RS activity ratio of 5 to 7 percentage points) were not detected by visual analysis. Computer assessment, on the other hand, provided a good estimate of both absolute and relative changes (“initial”-to-“late”) in DS:RS activity ratio of the phantom (r = 0.91, p < 0.0001). Thus, visual assessment of redistribution is limited by (1) difficulty in recognizing subtle “initial” defects and (2) inaccuracy in estimating extent of redistribution which occurs. Computer assessment of redistribution is superior to visual analysis in these respects.
A Bernstein TypeLpInequality for a Certain Class of Polynomials

Abstract Bernstein's classical theorem states that for a polynomialPof degree at mostn, max|z| = 1|P′(z)| ≤ n max|z| = 1|P(z)|. We give related results for polynomialsPsatisfying the conditionsP′(0) = P″(0) = ··· = P(m − 1)(0) = 0 andP(z) ≠ 0 for |z|
Product Quality and Imperfect Information

This paper considers markets in which consumers are imperfectly informed about both product prices and quality levels offered by firms. We characterize necessary and sufficient conditions for existence of the various equilibrium configurations of price and quality that can arise in two paradigm cases; when all consumers prefer higher quality and when all consumers prefer lower quality. Our results suggest that firms will exploit imperfect information by charging noncompetitive prices as well as by offering other than ideal quality in the former case, but only by changing noncompetitive prices in the latter case.
Taking the Pulse of Protein Interactions by EPR Spectroscopy

An article by Gaffney et al. in this issue establishes a method using pulse electron paramagnetic resonance spectroscopy to determine the location of protein substrates or binding partners with high precision.
Characterization of a cDNA encoding a novel heat-shock protein that binds to calmodulin.

A cDNA clone (pTCB48) encoding a calmodulin-binding protein was isolated by screening a [lambda]ZAPII cDNA expression library constructed from cell cultures of heat-shocked tobacco (Nicotiana tabacum L. cv Wisconsin-38) with metabolically labeled [35S]calmodulin. Calmodulin gel overlay analysis indicated that pTCB48 generated major peptides of 53, 36, and 22 kD and two minor peptides of 37 and 16 kD that bound calmodulin in a Ca2+-dependent manner. Deletion analysis of pTCB48 indicated that these and the minor calmodulin-binding proteins resulted from the insert. A probe made from the cDNA insert recognized two bands with sizes of 2.1 and 1.8 kb on northern blot analysis. Both species of RNAs were undetectable in the control and were induced after 15 min of heat-shock treatment at 38[deg]C. The intensity of the two bands reached maximum after 1.5 h of heat-shock treatment. The cDNA clone was not full length; however, the complete sequence was determined by 5[prime] rapid amplification of cDNA ends using nested antisense primers. The full-length cDNA contains 1648 bp and a single open reading frame of 1347 bp and is expected to encode a protein of approximately 50 kD. No significant homology with other reported genes and proteins was found. Structural predictions, deletion analysis, and gel overlay analysis suggested that the calmodulin-binding domain was a basic amphiphilic [alpha]-helix near the C terminus of the protein. The strong induction of the mRNA for this protein suggests a role for Ca2+/calmodulin-mediated process in the heat-shock response.
Cytosolic domain of the human mitochondrial fission protein fis1 adopts a TPR fold

Fis1 is an integral membrane protein that acts in the fission of mitochondria by controlling the assembly, membrane distribution, and function of the mitochondrial fission machinery. Here we report the 2.0 A resolution crystal structure of the cytosolic domain of human Fis1. The structure reveals an antiparallel array of α-helices homologous to tetratricopeptide repeat (TPR) proteins. Structure-based sequence alignments of Fis1 uncovered two divergent TPR motifs; the first TPR motif differs from the TPR consensus sequence by a three-residue insertion in a loop that may be important for function. These TPR helices create an amphiphilic, concave surface that can accommodate a helix or, possibly, an extended segment. Indeed, this putative binding surface mediates homodimer formation of Fis1 in the crystal. The structure of Fis1 provides insight into the architecture of the proposed binding interactions that mediate mitochondrial fission.
Nernst effect and flux flow in superconductors. III. Films of tin and indium

Flux motion induced by a temperature gradient and by an electrical current has been studied through the Nernst effect and the flux-flow resistivity in superconducting films of tin and indium. The film thickness ranged between 1 and 11 \ensuremath{\mu}m for tin and between 0.5 and 5 \ensuremath{\mu}m for indium. The data were taken at 2.0 K as a function of magnetic field and film thickness. In addition to the transport entropy of a fluxoid and the flux-flow resistivity, the critical thermal force and the critical Lorentz force, at which thermally induced and current-induced flux motion sets in, were determined. The transport entropy per unit length per unit flux, $\frac{{S}_{\ensuremath{\phi}}}{\ensuremath{\phi}}$, plotted versus film thickness was found to reach a maximum in Sn at about 7 \ensuremath{\mu}m and in In at about 3.5 \ensuremath{\mu}m. Around this maximum, $\frac{{S}_{\ensuremath{\phi}}}{\ensuremath{\phi}}$ was larger by a factor of 1.4 in Sn and 1.6 in In than the value calculated from the difference in entropy density of normal and superconducting material. With increasing film thickness, the critical Lorentz force decreased, while the critical thermal force increased. The discrepancy between the critical Lorentz force and the critical thermal force and its dependence on film thickness suggests that in the films the critical current flows along special channels at the surface for which the interaction with the fluxoids is strongly reduced. The results on Sn and In are consistent with the earlier results on Pb.
Evaluation of a Commercial Accelerometer (Tritrac-R3 D) to Measure Energy Expenditure During Ambulation

This study evaluated the ability of a commercially available accelerometer (Tritrac-R3 D) to measure energy expenditure in 16 subjects at rest (pre- and post-exercise) and during three different intensities of steady-state exercise (40-70 % of peak oxygen consumption [VO 2 peak]) while ambulating on a treadmill (no grade). Oxygen consumption and the respiratory exchange ratio from indirect calorimetry and the vector magnitude of triaxial accelerations were used to estimate energy expenditure using the manufacturers equations. There was a significant relationship between indirect calorimetry-derived energy expenditure and the energy expenditure derived from the accelerometer (r = 0.96). Using analysis of variance, there was no difference in the energy expenditure derived by the two methods at rest before exercise and during the three different intensities of ambulatory exercise.There was a significant difference between energy expenditure derived via indirect calorimetry and with the accelerometer during rest after exercise, probably due to the failure of the accelerometer to accurately estimate the energy expenditure associated with the progresssive decline in post-exercise oxygen consumption. Thus, this commerically available accelerometer appears to provide statistically acceptable estimates of energy expenditure at rest and during zero-grade treadmill ambulation up to about 70 % VO 2 peak. This may indicate its acceptable utility for large-scale population studies of physical activity involving this mode of movement. The failure of the accelerometer to accurately estimate energy expenditure during recovery from exercise may contribute to an underestimation of energy expenditure in some physically active individuals.
EQUIVALENT f AND j FACTORS FOR CONDENSATION INSIDE HORIZONTAL SMOOTH AND FINNED TUBES

For condensation inside horizontal smooth and finned tubes, the equivalent f and J factors can be employed to correlate the pressure drop and heat transfer performance, respectively. They are empirically found to be feqfl0-8Reeq -0"2 and Jeq=0.045 Reeq -0.2 where Reeq is the equivalent Reynolds number.
Individual and Organizational Characteristics of Effective Frontline Practitioner Performance: A Study of Los Angeles County HIV Testing Organizations

The authors examine the strategic contributions of three Frontline Practitioner (FP) attributes for effective HIV testing: risk assessment use, having specialized HIV training, and organizational test setting (nonprofit, for profit, and public). Data from 621 staff in 159 organizations in Los Angeles County are used to model individual and organizational correlates and use of risk assessment and measures of effective performance (volume of HIV tests, HIV-seropositive tests, and referrals to treatment). FPs with specialized training in HIV care situated in nonprofit outpatient clinics are more likely to use risk assessment. Nonprofit outpatient clinics, FPs with specialized training in HIV, and risk assessment use are associated with higher HIV test volume. FPs with specialized HIV training in nonprofit outpatient settings offer testing/counseling services qualitatively different from FPs in other settings.
The effect of left ventricular intracavitary volume on the unipolar electrogram.

In order to examine the effects of ventricular distention on the unipolar electrogram (UEG), an isolated rabbit heart modified Langendorff preparation was utilized. Left ventricular (LV) volume was adjusted using ionically permeable (PB = 9 hearts) or ionically impermeable balloons (IB = 4 hearts). LV UEGs, LV end-diastolic pressure (EDP), and LV minor axis dimension (MAD), as measured by ultrasonic transducers, were recorded. Three hundred twenty-five electrograms were digitized and analyzed with custom-designed software. In the PB group, a significant inverse linear relationship was found between UEG amplitude and changes in MAD (P 0.8 and a P value < 0.0001. There was also a significant inverse linear relationship between UEG slope and changes in MAD (P < 0.01). UEG amplitude and slope also exhibited a significant inverse relationship to changes in LV EDP, which were best described by a third order polynomial function. In the IB group, no significant relationship was found between either UEG amplitude or slope and MAD or EDP. In this study, intracavitary volume exerted a profound and significant influence on UEG amplitude and slope. This effect was due to increases in conductive intraventricular volume and not to myocardial stretch.
Rates of seasonal sediment reworking in Axiothella rubrocincta (Polychaeta: Maldanidae)

Sediment reworking rates of Axiothella rubrocincta (Johnson, 1901) (Polychaeta: Maldanidae) were measured in situ in Tomales Bay, California (USA), from August, 1969 through July, 1970. On the average, each adult worm (approximate fresh weight=1 g) reworks about 5 g dry sediment d-1 at a mean temperature of 13.4°C and a mean salinity of 31.8‰.Reworking rates are positively correlated with temperature and salinity, and negatively with sediment organic carbon, sedimentation rates and grain size. An inverse correlation exists between sediment reworking rates (g dry sediment g-1 wet wt of worm d-1) and g wet weight of worm. Sediment parameters deseribing unworked sediments are not significantly different from those for fecal sediments. Although these data suggest this species to be a “non-selective” deposit-feeder, it is more likely that it is faculatively selective.
Transient response of a dipole over a circular ground screen

The time-domain response of a vertical electric dipole located over a circular ground screen is considered. The relevant time-harmonic solution is used as a starting point. By making a number of approximations a very simple formula is obtained for the transient response of the far field when the dipole current moment is a ramp function of time. It is shown that for early times, the pattern response appears as if the ground screen were of infinite extent, while at very long times, the response approaches that expected for a homogeneous flat ground.