cssi/SciSciGPT-SciSciNet huggingface dataset:
Association of achalasia and eosinophilic esophagitis

Various esophageal motor disorders including achalasia have been sporadically reported in patients with eosinophilic esophagitis (EoE). The aim of this study was to determine the association between achalasia and EoE and to review the treatment outcomes in patients having both conditions. A retrospective search was conducted to identify the cases of achalasia having EoE over the last 10 years at a tertiary care hospital in the United States. Subsequently, a review of the literature was performed to search for cases of achalasia that have concurrent EoE. The retrospective study showed that 4 out of 512 patients of achalasia (<1 %) had concomitant EoE. The eosinophil counts were high (80–100/hpf) but the classic endoscopic features of EoE were present in only one patient. Long term outcome following treatment including botox, myotomy and corticosteroids was generally poor. Sixteen patients have been reported in the literature out of which five patients were reported in detail. Patients had good short term response to various therapies. The long term outcomes have not been reported. These studies suggest that a concurrence of these two conditions, although rare, may occur and may not be recognized by usual endoscopic features of EoE. Long term treatment outcomes, distinct from short term in the literature, may be poor.
Biochemical and morphological aspects of nitrogen dioxide toxicity and the effect of ethanol intake

Abstract Effect of short‐term exposure to 5 ppm of nitrogen dioxide (NO2) for 3 consecutive days on endogenous rat heart, serum and liver lactate dehydrogenase (LDH) was studied in male rats maintained on water or on 10% ethanol solution as the sole drinking fluid for 10 days preceding and during NO2 exposure. Animals were pair‐fed. Measurements of hepatic alcohol and aldehyde dehydrogenase were also made. Exposure to NO2 had little effect on body or liver weights from corresponding controls maintained on water. Ethanol intake increased liver weight in controls and in NO2‐treated rats. Endogenous heart LDH was significantly increased by the NO2 exposure compared to water drinking controls. Ethanol intake negated this effect on LDH in NO2‐exposed animals. Kinetic studies on NO2‐mediated action on heart LDH indicate higher Vmax and apparent Km values in NO2‐treated rats than in the corresponding controls, compared to normal values in NO2‐exposed ethanol drinking rats and their respective controls. No change...
Combining Ability for Maize Weevil Preference of Maize Grain

Maize weevil (Sitophilus zeamais Motschulsky) can cause severe grain damage in maize (Zea mays L.). Knowledge of inheritance of weevils' preference would be helpful in designing breeding strategies to develop more tolerant/resistant cultivars. This study was conducted to estimate general (GCA) and specific combining ability (SCA) for weevil preference/nonpreference. We used a 10-parent diallel cross in 1992 (Griffing's Method 3, Model 1). In 1993, due to insufficient seeds for some crosses, two eight-parent diallels (Griffing's Method 4, Model 1) were evaluated for GCA and SCA for maize weevil preference of maize grain. The two eight-parent diallels were subsets of the original 10-parent diallel. Second generation grain samples (100 g per plot) from F 1 crosses grown in the field were evaluated for maize weevil preference during 96-d (1992 experiment) and 108-d (1993 experiments) periods in the laboratory. The GCA, SCA, and reciprocal mean squares from the 10-parent diallel results from 1992 were significant. Both GCA and SCA were important in the analysis of the Subset 1 eight-parent diallel combined across years, whereas only GCA was significant in the Subset 2 eight-parent diallel combined across 1992 and 1993 data. Positive effects indicated non-preference and negative effects, preference of grain. Common parent means and GCA effects showed that L108 transmitted the most nonpreference and Mo17, the least nonpreference to its hybrids. In the 1992 data, significant positive GCA effects were detected in L108, L605, and L654 ; and significant negative GCA effects in B73, Mo17, L329, L729, and L266. Mo17 had a significant positive maternal effect (11.6), whereas B73 had a significant negative maternal effect (-11.93). The single cross Mo17 ? x B73 ? would possess more nonpreference than its reciprocal cross. Combined across years, analyses of two eight-parent diallel subsets of the original 10-parent diallel indicated GCA was more important than SCA in inheritance of preference/nonpreference.
Temporal Order of Cognitive and Functional Loss in a Nursing Home Population

OBJECTIVE: The order in which cognition and the ability to perform activities of daily living (ADLs) are lost in an institutionalized aged population was examined. Understanding the order of loss of function is important for preparing caregivers and planning of care. METHOD: The conditional probabilities of the inability to perform activity A when there exists the inability to perform activity B were explored in secondary analyses of cross-sectional data describing 408 nursing home residents. Residents' abilities to perform ADLs were rated by nursing staff using Linn and Linn's Rapid Disability Rating Scale (RDRS-2); cognitive functioning was rated by social workers and nursing staff using a modified version of Reisberg et al.'s Brief Cognitive Rating Scale (BCRS, with 4 axes: orientation, concentration, recent memory, and past memory). RESULTS: The results regarding ADLs confirm previous findings of a natural order of loss of ability (from the one lost first to last): bathing, dressing, grooming, toileting, walking, and eating. The examination of order in the loss of concentration, recent memory, past memory, and orientation revealed that these seem to be lost concurrently when the cutpoint was 3 (i.e., relatively normal functioning vs. moderate and severe dementia). When the cutpoint was 6 (i.e., severe dementia vs. higher levels of functioning), the order that emerged was: recent memory, past memory, concentration, and orientation. CONCLUSIONS: Although there is a significant relationship between loss of ability to perform ADLs and stage of cognitive impairment, the loss of any specific ADL is not uniquely related to any one stage of cognitive deterioration in this diverse population. This may be explained by the high prevalence of disease in this institutionalized population, as exemplified by the 60% suffering from arthritis and the 17% suffering from neurological disorders other than dementia.
Three-Coordinate N-Heterocyclic Carbene Nickel Nitrosyl Complexes

The N-heterocyclic carbene IPr serves as a supporting ligand in a series of low-coordinate nickel nitrosyl complexes which display a range of nitrosyl bonding modes. Attempts to form a cationic two-coordinate nickel nitrosyl led to the three-coordinate {[IPr][IPr′]Ni(NO)}+[BArF4]−, in which one of the IPr ligands exhibits unusual C(5) coordination.
The dual effect of rubidium ions on potassium efflux in depolarized frog skeletal muscle.

The effects of external Rb+ on the efflux of42K+ from whole frog sartorius muscles loaded with 305mm K+ and 120mm Cl− were studied. K+ efflux is activated by [Rb+]o less than about 40mm according to a sigmoid relation similar to that for activation by [K+]o. At [Rb+]o greater than 40mm, K+ efflux declines, although at [Rb+]o=300mm it is still greater than at [Rb+]o=0mm. For low concentrations, the increment in K+ efflux over that in K+- and Rb+-free solution, Δk, is described by the relation Δk=a[X+]on, for both K+ and Rb+. The value ofa is larger for Rb+ than for K+, while the values ofn are similar; the activation produced by a given [Rb+]o is larger than that by an equal [K+]o for concentrations less than about 40mm. Adding a small amount of Rb+ to a K+-containing solution has effects on K+ efflux which depend on [K+]o. At low [K+]o, adding Rb+ increases K+ efflux, the effect being greatest near [K+]o=30mm and declining at higher [K+]o; at [K+]o above 40mm, addition of Rb+ decreases K+ efflux. At [K+]o above 75mm, where K+ efflux is largely activated, Rb+ reduces K+ efflux by a factorb, described by the relationb=1/(1+c[Rb+]o). Activation is discussed in terms of binding to at least two sites in the membrane, and the reduction in K+ efflux by Rb+ at high [K+]o in terms of association with an additional inhibitory site.
Small area contact methods

Abstract In measuring the termal conductivity k of materials at high temperatures, error due to heat radiation may be suppressed by making the sample very small (less than 1 mm), or by carrying out the measurement in a small region of a larger sample. To do this, one causes electrical heating in a small region of the sample near a small area contact, observes the temperature rise indirectly by measuring the thermoelectric voltage δV or the change in resistance δR at the contact, and relates these to the applied voltage V, by equations which do not include factors dependent upon the detailed shape of the contact or of the sample. With this approach one can make complete measurements of thermal and electrical properties of very small samples, including the dependence on temperature of the electrical and thermal conductivities, the Seebeck coefficient, and the thermal diffusivity. Small area contact methods are being applied at our laboratories to three domains of measurements. For measurements at moderately high temperatures (up to 600°C), experimental techniques are being developed to exploit the advantages of working on a semi-micro scale. Since small samples are used, it is practical to use a hot plate in a bell jar, and a relatively small heater. A flexible arrangement which has been developed for experimental work permits the use of micromanipulators and allows visual observation of the sample under a microscope as it is being heated. For studying high-temperature thermoelectric materials, techniques have been evolved for making small area contacts in materials which tend to shatter at lower temperatures. In this case, a wire is dipped into the molten material, and the sample is then cooled to the range where measurements are made. For studies of thermal conductivity at very high temperatures (∼2000°C), where high solubility and high rate of diffusion become problems, the small area contact configuration has been modified to a necked-down region between two wider parts in a homogeneous sample. By observing the δR which occurs because of Joule heating, one can determine σ and k. In all the applications, the agreement with conventional measurements that has been obtained shows that the basic equations are correct. Various applications also show that the small area contact method is quite versatile and that it presents possibilities for avoiding or minimizing difficulties which occur in using conventional techniques. Experimental problems encountered in using the technique are being studied and have not, so far, proved to be excessively formidable.
Serotonergic control of androgen-induced dominance

The present study investigates the role of serotonergic systems in anabolic steroid-induced aggression. An animal model of aggressive dominance was used to assess the chronic effects of testosterone propionate. When rats that had become dominant following administration of testosterone propionate received serotonergic agonists with selectivity for the 5-HT1A receptor (8-OH-DPAT, buspirone, gepirone), the 5-H1B receptor (eltoprazine, TFMPP), or the 5-HT2A/2C receptor (DOM), a dose-dependent decrease in dominance was demonstrated. Pretreatment with three serotonergic antagonists (pizotyline, pirenpirone, and pindolol) blocked agonist-induced reductions in dominance in varying degrees. Nonserotonergic agonists with CNS depressant effects were also tested in dominant animals. The benzodiazepine, chlordiazepoxide, did not reduce dominance except at doses that interfered with motor behavior. The opioid agonist, morphine, dose dependently decreased dominance, but this effect was reversible with administration of the serotonergic antagonist, pirenpirone, suggesting the antidominant effect of morphine had a serotonergic component. Biochemical experiments demonstrated that following chronic testosterone propionate, there was a decrease in levels of 5-HT and 5-HIAA in the hippocampus but not in the striatum or the frontal cortex. Chronic testosterone propionate also caused an increase in the affinity of [3H]8-OH-DPAT for the 5-HT1A receptor but no corresponding change in the density of 5-HT1A binding sites in the hippocampus. There was also no change in the properties of the 5-HT2 receptor in the frontal cortex following chronic testosterone propionate. These data suggest that serotonergic systems may play an important role in the control of anabolic steroid-induced aggressive dominance.
KIT signaling regulates MITF expression through miRNAs in normal and malignant mast cell proliferation.

Activating mutations in codon D816 of the tyrosine kinase receptor, KIT, are found in the majority of patients with systemic mastocytosis. We found that the transcription factor, microphthalmia-associated transcription factor (MITF), is highly expressed in bone marrow biopsies from 9 of 10 patients with systemic mastocytosis and activating c-KIT mutations. In primary and transformed mast cells, we show that KIT signaling markedly up-regulates MITF protein. We demonstrate that MITF is required for the proliferative phenotype by inhibiting colony-forming units with sh-RNA knockdown of MITF. Furthermore, constitutively active KIT does not restore growth of primary MITF-deficient mast cells. MITF mRNA levels do not change significantly with KIT signaling, suggesting posttranscriptional regulation. An array screen from mast cells identified candidate miRNAs regulated by KIT signaling. We found that miR-539 and miR-381 are down-regulated by KIT signaling and they repressed MITF expression through conserved miRNA binding sites in the MITF 3′-untranslated region. Forced expression of these miRNAs suppressed MITF protein and inhibited colony-forming capacity of mastocytosis cell lines. This work demonstrates a novel regulatory pathway between 2 critical mast cell factors, KIT and MITF, mediated by miRNAs; dysregulation of this pathway may contribute to abnormal mast cell proliferation and malignant mast cell diseases.
Lordosis in female rats following medial forebrain bundle lesions.

In the first experiment, ovariectomized rats given weekly injections of estrogen and progesterone which were relatively unresponsive during preoperative testing received bilateral medial forebrain bundle (MFB) lesions. Postoperative lordosis quotients were significantly elevated. In the second experiment, MFB lesion and sham lesion rats were tested for responsiveness to decreasing doses of estrogen. Lesions had no significant effect in this experiment. In the final experiment, MFB lesions significantly increased the duration of receptivity following single injections of estrogen and progesterone. These results suggest that, like the preoptic area, under some conditions the MFB may play a role in the suppression of lordosis.
Detection of amino acids in artificial nectars by two tropical ants, Leptothorax and Monomorium.

Many ants forage at extrafloral nectar on plants and provide the plant with some measure of protection from herbivory. These nectars contain sugars, amino acids and, often, other compounds. The role of amino acids in attracting ants to extrafloral nectars was studied by baiting with Karo-syrup-based solutions. Control (without amino acids) and experimental (with amino acids) solutions were placed in second growth forest in Trinidad, W.I. The number of ants visiting the solutions was counted at fiveminute intervals for 45 min. In tests of solutions with only one amino acid, both Leptothorax sp. and Monomorium sp. visited solutions with alanine, arginine, serine, cysteine, methionine or aspartic acid more frequently than sugaronly controls. Monomorium preferred control solutions to tyrosine solutions; Leptothorax preferred control solutions to histidine solutions. Leptothorax did not discriminate between control and tyrosine solutions; Monomorium did not discriminate between control and histidine solutions. However, in six of eight tests of combinations of amino acids, ants visited control solutions more frequently than experimental solutions. These results suggest that ants can act as selective agents, favoring plants with particular amino acids in their nectars.
Quantum mechanical control systems

Following a pioneering work on modelling of quantum mechanical control systems, the model is generalized within the framework of the Lagrangian and Hamiltonian formalisms.
Oxygen flux across the environmental interface of teleost cornea.

WHILE the use of oxygen directly from the environment by mammalian cornea was long suspected and had even been shown qualitatively, oxygen uptake by the human cornea in vivo has only recently been measured1–3.
Prenatal arsenic exposure alters the programming of the glucocorticoid signaling system during embryonic development

The glucocorticoid system, which plays a critical role in a host of cellular functions including mood disorders and learning and memory, has been reported to be disrupted by arsenic. In previous work we have developed and characterized a prenatal moderate arsenic exposure (50ppb) model and identified several deficits in learning and memory and mood disorders, as well as alterations within the glucocorticoid receptor signaling system in the adolescent mouse. In these present studies we assessed the effects of arsenic on the glucocorticoid receptor (GR) pathway in both the placenta and the fetal brain in response at two critical periods, embryonic days 14 and 18. The focus of these studies was on the 11β-hydroxysteroid dehydrogenase enzymes (11β-HSD1 and 11β-HSD2) which play a key role in glucorticoid synthesis, as well as the expression and set point of the GR negative feedback regulation. Negative feedback regulation is established early in development. At E14 we found arsenic exposure significantly decreased expression of both protein and message in brain of GR and the 11β-HSD1, while 11β-HSD2 enzyme protein levels were increased but mRNA levels were decreased in the brain. These changes in brain protein continued into the E18 time point, but mRNA levels were no longer significantly altered. Placental HSD11B2 mRNA was not altered by arsenic treatment but protein levels were elevated at E14. GR placental protein levels were decreased at E18 in the arsenic exposed condition. This suggests that arsenic exposure may alter GR expression levels as a consequence of a prolonged developmental imbalance between 11β-HSD1 and 11β-HSD2 protein expression despite decreased 11HSDB2 mRNA. The suppression of GR and the failure to turn down 11β-HSD2 protein expression during fetal development may lead to an altered set point for GR signaling throughout adulthood. To our knowledge, these studies are the first to demonstrate that gestational exposure to moderate levels of arsenic results in altered fetal programming of the glucocorticoid system.
Historians and Moral Evaluations

The reappearance of the question of moral judgments by historians makes a reappraisal of the issues timely. Almost all that has been written on the subject addresses only the propriety of moral judgments (or morally charged language) in the written texts historians produce. However, historians have to make moral choices when selecting a subject upon which to write; and they make a tacit moral commitment to write and teach honestly. Historians usually dislike making explicit moral evaluations, and have little or no training in how to do so. They can argue it's not their job; they are only finders of fact. Historians holding a determinist view of actions do not think it appropriate to blame people for doing what they couldn't help doing; for those believing there is an overall pattern to history, individual morality is beside the point. Finally, since earlier cultures had values different from ours, it seems unjust to hold them to contemporary standards. This essay modifies or rejects these arguments. Some historians have manifested ambivalence, acknowledging it is difficult or impossible to avoid making moral evaluations (and sometimes appropriate to make them). Ordinary-language philosophers, noting that historiography has no specialized vocabulary, see it as saturated by the values inherent in everyday speech and thought. I argue that the historicist argument about the inevitably time-bound limitation of all values is exaggerated. Historians who believe in the religious grounding of values (like Lord Acton) obviously disagree with it; but even on a secular level, morals are often confused with mores. If historians inevitably make moral evaluations, they should examine what philosophical ethicists—virtue ethicists, deontologists, and consequentialists—have said about how to make them; and even if they find no satisfactory grounding for their own moral attitudes, it is a brute fact that they have them. I end with an argument for “strong evaluations”—neither treating them as a troublesome residue in historiography nor, having despaired of finding a solid philosophical ground for moral evaluations, concluding that they are merely matters of taste. I believe historians should embrace the role of moral commentators, but that they should be aware that their evaluations are, like all historical judgments, subject to the criticisms of their colleagues and readers. Historians run little risk of being censorious and self-righteous; the far greater danger is acquiescing in or contributing to moral confusion and timidity.
DNA-responsive inflammasomes and their regulators in autoimmunity

Upon sensing microbial and self-derived DNA, DNA sensors initiate innate immune responses. These sensors include the interferon (IFN)-inducible Toll-like receptor 9 (TLR9) and PYHIN proteins. Upon sensing DNA, cytosolic (murine Aim2 and human AIM2) and nuclear (IFI16) PYHIN proteins recruit an adaptor protein (ASC) and pro-caspase-1 to form an inflammasome, which activates caspase-1. The activated caspase-1 cleaves pro-IL-1β and pro-IL-18 to generate active forms. However, upon sensing cytosolic DNA, the IFI16 protein recruits STING to induce the expression of type I IFN. Recognition of self DNA by innate immune cells contributes to the production of increased levels of type I IFN. Given that the type I IFNs modulate the expression of inflammasome proteins and that the IFN-inducible proteins inhibit the activity of DNA-responsive inflammasomes, an improved understanding of the molecular mechanisms that regulate the activity of DNA-responsive inflammasomes is likely to identify new therapeutic targets to treat autoimmune diseases.
Cell corrections in precision colorimetry

Abstract Errors introduced by the non-uniformity of cells limit the practical application of precision colorimetric theory. The methods of correcting for these errors are not readily evident from the theoretical discussions in recent literature. Three methods of correction for variations in cell length and absorbance are presented.
EFFECTS OF MUTATION OF THE OLF-1 MOTIF ON TRANSGENE EXPRESSION IN OLFACTORY RECEPTOR NEURONS

We have examined the effect of mutating the Olf-1 binding motif of the olfactory marker protein (OMP) promoter in determining olfactory neuron-specific gene expression in adult tissues and during embryonic development. The proximal Olf-1 motif located 170 nucleotides upstream of the transcription start site of the OMP gene was mutated to prevent its interaction with the Olf-1 factor in vitro. The wild-type and mutated fragments of the OMP gene extending from -239 to +55 nucleotides relative to the transcription start site were used to direct expression of a lacZ reporter gene in transgenic mice. The transgenic animals were analyzed for cell-specific and developmental expression of the reporter gene. We demonstrate that the mutation that prevents interaction of Olf-1 with its binding site does not alter the temporal and spatial patterns of gene expression in olfactory sensory neurons but does alter the specificity and level of expression in other neuronal populations. These observations are consistent with our demonstration that the mutated Olf-1 site interacts with nuclear proteins present in the central nervous system (CNS).
Differential susceptibility of parasitized and nonparasitized larvae of Trichoplusia ni to a nuclear polyhedrosis virus

Abstract Nonparasitized second-instar larvae of Trichoplusia ni were twice as susceptible (at the LD 50 level) to the singly enveloped T. ni nuclear polyhedrosis virus as those parasitized by Hyposoter exiguae (Hymenoptera: Ichneumonidae). The LD 50 values for nonparasitized and parasitized larvae were 1.58 × 10 3 and 3.16 × 10 3 polyhedra/ml of diet, respectively. The LD 95 value for parasitized larvae was approximateely 5 times higher than that for nonparasitized larvae. The slopes ( b values) were 1.2 for parasitized larvae and 1.7 for nonparasitized larvae. The LT 50 values for parasitized larvae also were significantly longer than those for nonparasitized larvae. No significant difference was found between the food consumption of parasitized and nonparasitized T. ni larvae.
Renormalization-group theory and calculations of tricritical behavior

The conventional renormalization-group analysis of the tricritical behavior of a metamagnet is completed by a description of the first-order transition below the tricritical temperature, and the conditions for the discontinuity in the magnetization are explicitly verified in an Ising spin model. The singularity structure of the crossover scaling function is derived from relations between the scaling fields for the critical and tricritical fixed points. Numerical calculations illustrating various aspects of the theory are given for a square-lattice Ising model in a four-cell cluster approximation.
Unified Treatment of Lifting Atmospheric Entry

This paper presents a unified treatment of the effect of lift on peak acceleration during atmospheric entry. Earlier studies were restricted to different regimes because of approximations invoked to solve the same transcendental equation. This paper shows the connection between the earlier studies by employing a general expression for the peak acceleration and obtains solutions to the transcendental equation without invoking the earlier approximations. Results are presented and compared with earlier studies where appropriate.
Pole in kcotdelta for doublet, s-wave, n-d scattering

The position of the pole in $kcot\ensuremath{\delta}$, for doublet, $s$-wave, $n$-$d$ scattering, and its residue are shown to be correlated with the doublet scattering length. An approximate, analytic solution of the $\frac{N}{D}$ equations of Barton and Phillips indicates a linear dependence on the doublet scattering length for the pole position, and a quadratic dependence for the residue. These relationships are tested by means of exact numerical solutions of $\frac{N}{D}$ equations and three-particle equations with separable two-particle interactions, and found to be qualitatively correct. The approximate, analytic solution of the $\frac{N}{D}$ equations leads to a formula for $kcot\ensuremath{\delta}$, which is of the same form as the phenomenological formula used previously by other authors. A formalism is presented which makes it possible to parametrize the effect of the omitted portion of the left hand cut in an $\frac{N}{D}$ calculation.
A simplified time-lapse cinemicrographic unit.

SUMMARY Time-lapse mechanisms, specially intended for use in conjunction with the microscope, are described. They are extremely simplified and of very low cost. An unmodified camera is driven continuously at low speed and the exposure is made by means of an electronic flashlight. Synchronization of the flash is secured by a microswitch which activates the flashlight when the shutter of the camera is open. Two equipments (for 35 mm and 16 mm film) of this type were built and found very satisfactory.
A brief comparison of technologies available in the computer science classroom

The paper briefly describes and compares various technologies available in computer science classrooms, including presentation software and pen-based technologies. The comparison focuses on how these different technologies help support information flow between teacher and student. The author's use of a pen-based classroom management system is described, as is an assignment for Computer Science 1 involving pen-based algorithms.
A multi-windowed environment for simultaneous visualization of related algorithms on the World Wide Web

Using algorithm visualization, we can depict the execution of an algorithm as a sequence of graphical snapshots, the viewing of which is controlled by the user. Although the delivery of such visualizations over the Web greatly increases their accessibility, Web-based environments for viewing algorithms often lack the richness of features that characterize similar viewing environments on standalone machines. Here we describe enhancements recently made to such a Web-based system. These enhancements conveniently present a variety of windowing options that allow the user to simultaneously view multiple snapshots. These snapshots may depict (1) similar views of the states of an algorithm over a range of time, (2) different views of the state of an algorithm at a given point in time, or (3) side-by-side comparisons of different algorithms that solve the same problem. We illustrate each of these options using variations of the quick sort algorithm.
The ins and outs of angiotensin processing within the kidney

The kidney is a key target organ for bioactive components of the renin-angiotensin system (RAS); however, various renal cells such as the tubular epithelium contain an intrinsic RAS. The renal RAS can be functionally divided into ANG II-AT1 receptor and ANG-(1–7)-AT7/Mas receptor arms that functionally oppose one another. The current review considers both extracellular and intracellular pathways that potentially govern the formation and metabolism of angiotensin peptides within the renal proximal tubules.
Guanylate kinase, induced fit, and the allosteric spring probe.

Since the introduction of the induced-fit theory by D. E. Koshland Jr., it has been established that conformational motion invariably accompanies the execution of protein function. The catalytic activity of kinases, specifically, is associated with large conformational changes (;1 nm amplitude). In the case of guanylate kinase, upon substrate binding, the LID and nucleotide-monophosphate-binding domains are brought together and toward the CORE with large concerted movements about the a3 (helix 3) axis. However, whether the change in conformation mostly affects the catalytic rate or mostly increases binding affinities for one or the other substrate is unclear. We investigate this question using a nanotechnology approach based on mechanical stress. Using an "allosteric spring probe", we bias conformational states in favor of the ''open'' (substrate-free) conformation of the enzyme; the result is that the binding constant for the substrate guanosine monophosphate (GMP) is reduced by up to a factor of 10, whereas the binding constant for adenosine triphosphate (ATP) and the catalytic rate are essentially unaffected. The results show that the GMP-induced conformational change, which promotes catalysis, does not promote ATP binding, consistent with previous mutagenesis studies. Furthermore, they show that this conformational change is of the induced-fit type with respect to GMP binding (but not ATP binding). We elaborate on this point by proposing a quantitative criterion for the classification of conformational changes with respect to the induced-fit theory. More generally, these results show that the allosteric spring probe can be used to affect enzymatic activity in a continuously controlled manner, and also to affect specific steps of the reaction mechanism while leaving others unaffected. It is presumed that this will enable informative comparisons with the results of future molecular dynamics or statistical mechanics computations.
Numerical simulations of effects of micro vortex generators using immersed-boundary methods

This work presents an immersed-boundary technique for compressible, turbulent flows and applies the technique to simulate the effects of micro vortex generators in controlling oblique-shock/turbulent boundary-layer interactions. The Reynolds-averaged Navier-Stokes equations, closed using the Menter k-ω turbulence model, are solved in conjunction with the immersed-boundary technique. The approach is validated by comparing solutions obtained using the immersed-boundary technique with solutions obtained on a body-fitted mesh and with experimental laser Doppler anemometry data collected at Cambridge University for Mach 2.5 flow over single micro vortex generators. Simulations of an impinging oblique-shock boundary-layer interaction at Mach 2.5 with and without micro vortex-generator flow control are also performed, considering the development of the flow in the entire wind tunnel. Comparisons are made with experimental laser Doppler anemometry data and surface-pressure measurements from Cambridge University and an analysis of the flow structure is performed. The results show that three dimensional effects initiated by the interaction of the oblique shock with the sidewall boundary layers significantly influence the flow patterns in the actual experiment. The general features of the interactions with and without the micro vortex-generator array are predicted to good accord by the Reynolds-averaged Navier-Stokes/ immersed-boundary model.
Measuring the roughness of interfaces

Abstract Measuring the roughness of interfaces is of primary importance in many areas of science and technology. Previously used techniques, such as estimation of the fractal dimension and Fourier analysis, have their drawbacks. In this paper, we propose a new methodology that relies on ‘geometric thermodynamics’ of curves and surfaces. The technique is well suited to situations where surfaces are known only with finite resolution.
Does Less Invasive Spine Surgery Result in Increased Radiation Exposure? A Systematic Review

Radiation exposure to patients and spine surgeons during spine surgery is expected. The risks of radiation exposure include thyroid cancer, cataracts, and lymphoma. Although imaging techniques facilitate less invasive approaches and improve intraoperative accuracy, they may increase radiation exposure. We performed a systematic review to determine whether (1) radiation exposure differs in open spine procedures compared with less invasive spine procedures; (2) radiation exposure differs in where the surgeon is positioned in relation to the C-arm; and (3) if radiation exposure differs using standard C-arm fluoroscopy or fluoroscopy with computer-assisted navigation. A PubMed search was performed from January 1980 to July 2013 for English language articles relating to radiation exposure in spine surgery. Twenty-two relevant articles met inclusion criteria. Level of evidence was assigned on clinical studies. Traditional study quality evaluation of nonclinical studies was not applicable. There are important risks of radiation exposure in spine surgery to both the surgeon and patient. There is increased radiation exposure in less invasive spine procedures, but the use of protective barriers decreases radiation exposure. Where the surgeon stands in relation to the image source is important. Increasing the distance between the location of the C-arm radiation source and the surgeon, and standing contralateral from the C-arm radiation source, decreases radiation exposure. The use of advanced imaging modalities such as CT or three-dimensional computer-assisted navigation can potentially decrease radiation exposure. There is increased radiation exposure during less invasive spine surgery, which affects the surgeon, patient, and operating room personnel. Being cognizant of radiation exposure risks, the spine surgeon can potentially minimize radiation risks by optimizing variables such as the use of barriers, knowledge of position, distance from the radiation source, and use of advanced image guidance navigation-assisted technology to minimize radiation exposure. Continued research is important to study the long-term risk of radiation exposure and its relationship to cancer, which remains a major concern and needs further study as the popularity of less invasive spine surgery increases.
Influencing Social Workers to Use Research Evidence in Practice: Lessons from Medicine and the Allied Health Professions:

This study sought to identify lessons for social workers from the health care research on influencing practitioners to use evidence-based practices (EBP). Research reviews of strategies to influenc...
Use of self-collected vaginal specimens for detection of Chlamydia trachomatis infection

Abstract Objective: To evaluate the efficacy of a self-collected vaginal introital specimen, obtained by women using only an instruction booklet as a guide, for the detection of Chlamydia trachomatis using polymerase chain reaction (PCR). Methods: Comparison analysis in an Urban hospital clinic, using a convenience sample of 101 women undergoing screening or treatment for C trachomatis infection. Subjects were given an illustrated instruction booklet and were asked to collect a single specimen from the vaginal introitus using the Amplicor collection kit. Cervical and introital specimens then were obtained by clinicians. The presence of C trachomatis in patient-collected versus clinician-collected samples was determined by PCR. Discordant specimens were retested by PCR, using primer pairs to the C trachomatis major outer membrane protein gene, and were screened for the presence of PCR assay inhibitors. Results: Ninety-nine subjects completed the self-collection. Sixty-two percent were adolescents and 17% spoke English as their second language. Forty-three percent had never used tampons, and 36% had never looked at their own genitals. Twenty-eight cervical specimens (28%), 32 clinician-collected introital specimens (32%), and 33 self-collected introital specimens (33%) were positive for C trachomatis infection. All clinician-collected introital specimens that were positive for C trachomatis and all cervical specimens that were positive for C trachomatis were positive on self-test. Compared with clinician-collected introital specimens, self-collected specimens had a sensitivity of 100% and a specificity of 98.5%. Compared with cervical specimens, self-collected specimens had a sensitivity of 100% and a specificity of 93.4%. After discrepant analysis, self-test had a sensitivity of 100% and a specificity of 94.6% for detection of C trachomatis cervical infection. Conclusion: Self-collection of introital samples is both sensitive and specific in screening for C trachomatis.
The welfare economics of dominant-firm acquisitions

The main results of this paper provide some analytic underpinning for a strict horizontal merger policy relating to dominant firms. However, even under standard assumptions, examples have been demonstrated where dominant/fringe firm mergers increase welfare. Most of these examples imply shutting down acquired facilities, a practice regarded as unfavorable evidence by the court in theStandard Oil case; consequently, they do not by themselves seem to offer much hope for raising economies as an antitrust defense. Finally, it should be noted that this paper has considered only single-product economies; economies of scope arising in multi-product (and multi-market) contexts could be large enough to justify dominant/fringe firm mergers9.
Identification and Characterization of Small-Molecule Inhibitors of Yop Translocation in Yersinia pseudotuberculosis

Type three secretion systems (TTSSs) are virulence factors found in many pathogenic Gram-negative species, including the family of pathogenic Yersinia spp. Yersinia pseudotuberculosis requires the translocation of a group of effector molecules, called Yops, to subvert the innate immune response and establish infection. Polarized transfer of Yops from bacteria to immune cells depends on several factors, including the presence of a functional TTSS, the successful attachment of Yersinia to the target cell, and translocon insertion into the target cell membrane. Here we employed a high-throughput screen to identify small molecules that block translocation of Yops into mammalian cells. We identified 6 compounds that inhibited translocation of effectors without affecting synthesis of TTSS components and secreted effectors, assembly of the TTSS, or secretion of effectors. One compound, C20, reduced adherence of Y. pseudotuberculosis to target cells. Additionally, the compounds caused leakage of Yops into the supernatant during infection and thus reduced polarized translocation. Furthermore, several molecules, namely, C20, C22, C24, C34, and C38, also inhibited ExoS-mediated cell rounding, suggesting that the compounds target factors that are conserved between Pseudomonas aeruginosa and Y. pseudotuberculosis. In summary, we have identified 6 compounds that specifically inhibit translocation of Yops into mammalian cells but not Yop synthesis or secretion.
Visually evoked potentials and selective masking with patterned flashes of different spatial frequencies

Abstract Human visually evoked responses (VERs) to pairs of checkerboard patterned light flashes (40 msec interstimulus interval) were investigated in an attempt to assess the electrophysiological nature of temporal visual processing as a function of the spatial frequency of patterned stimuli involved. Four stimuli, all of equal mean luminance, were employed: a diffuse flash and checkerboards with fundamental spatial frequencies of 0.5, 1.0 and 4.0 c/deg (check-sizes of 60′, 30′ and 7.5′). VERs from four adult humans were recorded monopolarly over the occipital area of the scalp (O = to ear reference) and averaged. The purpose of the experiment was to test whether the existence of visual information channels selectively tuned to a specific range of spatial frequencies would be revealed in terms of selective masking effects among the various stimulus combinations. The results indicated that the amplitude of VERs approximately 110 msec after stimulation was particularly sensitive to the presence and size of the pattern. Data were quantified in terms of variations in amplitude of this component as a function of the nature of pattern in the first and second flash. This variability measure indicated that pattern processing of one flash of the pair was impaired by the presence of pattern in the preceding or following flash (forward and backward masking effects respectively). When the first flash contained pattern, the contribution of the second flash was always less than that of the first, forward masking being most pronounced. The 7.5 and 30′ check-sizes were found to be the most effective forward maskers, and elicited the largest amplitude negative potentials at the 110-msec latency after flash onset. Forward masking, furthermore, was specific to the spatial frequency of the pattern in the first (masking) flash, electrophysiological masking being greatest when identical as compared to dissimilar spatial frequencies were presented in the flash pair. This finding of selective masking lends support to the notion that there are multiple visual channels, each selectively sensitive to a limited range of spatial frequencies.
Multinational corporations and export quality

Abstract We investigate the effects of spillovers on quality of exports emanating from investment in product quality by multinational corporations, operating in less developed countries. By using a duopoly set up, we show that under price competition these spillovers enhance the quality of exports by less developed countries. We also show that this result is valid under quantity competition.
Time-Dependent Predictive Accuracy in the Presence of Competing Risks

Competing risks arise naturally in time-to-event studies. In this article, we propose time-dependent accuracy measures for a marker when we have censored survival times and competing risks. Time-dependent versions of sensitivity or true positive (TP) fraction naturally correspond to consideration of either cumulative (or prevalent) cases that accrue over a fixed time period, or alternatively to incident cases that are observed among event-free subjects at any select time. Time-dependent (dynamic) specificity (1-false positive (FP)) can be based on the marker distribution among event-free subjects. We extend these definitions to incorporate cause of failure for competing risks outcomes. The proposed estimation for cause-specific cumulative TP/dynamic FP is based on the nearest neighbor estimation of bivariate distribution function of the marker and the event time. On the other hand, incident TP/dynamic FP can be estimated using a possibly nonproportional hazards Cox model for the cause-specific hazards and riskset reweighting of the marker distribution. The proposed methods extend the time-dependent predictive accuracy measures of Heagerty, Lumley, and Pepe (2000, Biometrics 56, 337-344) and Heagerty and Zheng (2005, Biometrics 61, 92-105).
Infrared spectra of matrix isolated alkali metal metaborates

Abstract The infrared spectra of M BO 2 molecules ( M = Li n , 6 Li, Na, K, Rb, and Cs ) isolated in a matrix of solid argon or krypton at liquid hydrogen temperature are reported. Above 500 cm −1 , three absorptions are found which exhibit small monotonic change with increasing mass of the alkali metal. These absorptions, consisting of 10 B- 11 B doublets correspond to modes involving essentially the BO 2 portion of the molceules, the measured frequencies being very similar to those of the BO 2 group in B 2 O 3 or HBO 2 . The spectra below 500 cm −1 consist of at most two absorptions which are characterized by negligible 10 B- 11 B shifts and large decreases in frequency with increasing mass of the alkali metal. These absorptions are attributed to vibrational modes involving principally the motion of the metal atoms. The total number of observed fundamentals satisfies the selection rules for a C s molecular symmetry. A force constant analysis of the data assuming an M OBO arrangement of atoms suggests an M OB bond angle in the neighborhood of 90°, a value consistent with the results of electron diffraction studies.
PSMalloc: content based memory management for MPI applications

Multicore processors have come to dominate the commodity market upon which many large scale systems are based. The number of cores is increasing with the speed of Moore's law and as a direct consequence, the memory available per core is decreasing, often severely limiting the problem size for programs running on such platforms. Thus, mechanisms to store memory efficiently in DRAM, increasing the effective capacity of DRAM, in a way that requires no reprogramming, would dramatically increase the benefits of multicore nodes for large scale systems.We observe that MPI programs replicate a significant amount of data across all processes. With multiple MPI tasks running on a single node, this replication leads to identical data residing in multiple locations in that node's DRAM, an ideal candidate for potential savings. We have found that most of the redundant data resides in the heap. Thus, smart memory allocation can remove this redundancy and increase the effective memory capacity.We present PSMalloc, a memory allocation library that keeps a single copy of identical pages from a set of MPI tasks. PSMalloc is implemented as a user level library that can be linked at runtime, avoiding changes in the application or the operating system. To the best of our knowledge, our work is the first that reduces physical memory footprints of MPI tasks in a multicore node without requiring kernel level modifications. We experiment with four MPI applications from the ASC Sequoia benchmark suite and show that we can achieve a reduction in memory footprint up to 22% and 11.18% in average.