cssi/SciSciGPT-SciSciNet huggingface dataset:
A PROGRAM TO REDUCE DISCHARGE DELAYS IN AN NICU. 1412

We wished to test the hypothesis that a program designed to identify the causes of discharge delays (DD) would significantly reduce the length of stay in our metropolitan academic regional NICU. We reviewed all admissions from January 1994 through November 1995 (n=1396). A DD was defined as any delay in discharge not related to illness after the attending neonatologist cleared the baby for release. DDs were further divided according to cause into medical, administrative, social work, family-related, and “other” categories. All admissions were reviewed by one of the authors. Potential DDs were identified and tracked daily according to established criteria. Actual DDs were then reviewed on a monthly basis at an open staff meeting attended by representatives our multi-disciplinary team. 111 DDs accounting for 481 patient days were identified, 83 DD/302 patient days in 1994 and 28 DD/179 patient days in 1995. 13.9% of DDs weighed <1000 gms. at birth, and 35.6% were <1500 gms. at birth. DDs ranged from 1-34 days, with an average of 4.3 days added/case. Babies with DDs had a case mix index (CMI) of 9.70. The average CMI for the NICU during 1994 was 6.25, and for 1995 to date was 5.18, with an overall average of 5.71 for the entire period. 44% of DDs had private insurance, 55% had Medicaid, and 1% were self-pay. 84/111 DDs were caused by circumstances beyond the control of the primary care team. A further 24/111 DDs were the result of our policy requiring a 48-hour period free of apnea/bradycardia alarms prior to discharge. Average savings per day were based on the diagnosis-related group (DRG) of each DD patient. Discharge delays for 1994 cost $226,298. ($749/day). For 1995, DDs cost $36,132($202/day), for a total cost of $262,431. Total savings in 1995 vs. 1994 was$190,166 ($548/day). Despite their low birth weight and relatively severe illness (high CMI), we believe that heightened staff awareness and ongoing monitoring of potential DDs can result in a significant reduction in length of stay and a significant cost savings.
P1144 Impact de l’activité physique et de la saxagliptine sur les mitochondries dans le système vasculaire des diabétiques

Introduction L’activite physique (AP) diminue le risque cardiovasculaire et la mortalite toutes causes confondues. L’adaptation mitochondriale est induite par l’AP dans de nombreux organes cibles, dont le systeme vasculaire. Dans un systeme vasculaire sain, l’AP regule les mitochondries et leurs regulateurs tels l’oxyde nitrique synthetase endotheliale (eNOS), les sirtuines (SIRT), le coactivateur PPARγ alpha (PGC1-α). Patients et methodes Nous avons teste l’hypothese que l’adaptation mitochondriale vasculaire a l’AP est perturbee par le diabete ; La saxagliptine, inhibiteur DPP-4 restaurera cette reponse par l’activation de l’eNOS, SIRT et/ou PGC1-α. Nous avons examine une AP avec ou sans saxagliptine chez le rat Goto-Kakizaki (GK), un modele de diabete type 2. Des rats mâles dans des groupes d’AP ou sedentaire ont couru sur un tapis roulant pendant 8 jours. Les aortes ont ete prelevees, subi une analyse par Western. Les complexes mitochondriaux (CM) I-V et les molecules de signalisation en amont ont ete recherches. Resultats Dans le groupe AP, on a observe une diminution de l’expression des CM I-V. L’association AP+saxagliptine a induit une augmentation significative (p = 0,0306) du complexe IV (36 %) compare au groupe sedentaire+saxaxagliptine. cette augmentation etait aussi observee au niveau de l’expression des CM totaux. Augmentation significative de 29 % de l’effet sur la teneur en proteine eNOS (p = 0,0268) dans le groupe AP+saxagliptine compare au groupe sedentaire+saxagliptine. Effet significatif de l’AP+saxagliptine sur l’expression du PGC1-α (augmentation de 26 %, p = 0,018) et de la saxagliptine seule sur l’augmentation de l’expression de SIRT3 (p = 0,049). En conclusion, pas d’induction d’expression de l’eNOS, PGC1-α, SIRT3 ou des proteines mitochondriales par l’AP, la saxagliptine associee a l’AP a amplifie la reponse d’eNOS, du PGC1-α, de SIRT3 et la reponse mitochondriale a l’AP dans le diabete. Conclusion Nos donnees suggerent que la saxagliptine restaure l’adaptation mitochondriale saine a l’AP dans le diabete.
Field use and evaluation of a vaccine for bovine staphylococcic mastitis.

Abstract A commercial staphylococcic vaccine was evaluated for the treatment and prevention of Staphylococcus aureus mastitis. There was no significant therapeutic effect upon the udder infections or the clinical incidence of mastitis in 13 cows with chronic mastitis. Prophylactic vaccination in two dairy herds resulted in an insignificant decrease in the clinical incidence of mastitis of both herds and a significant decrease in the rise of infected quarters in one herd. Vaccination was of limited value for controlling S. aureus mastitis.
Bounds on the area under the ROC curve

Upper and lower bounds are derived for the area under the receiver-operating-characteristic (ROC) curve of binary hypothesis testing. These results are compared with the area-under-the-curve (AUC) approximation and the AUC lower bound recently reported by Barrett et al. [J. Opt. Soc. Am A15, 1520 (1998)].
Oh, $#*@! Exascale! The Effect of Emerging Architectures on Scientific Discovery

The predictions for exascale computing are dire. Although we have benefited from a consistent supercomputer architecture design, even across manufacturers, for well over a decade, recent trends indicate that future high-performance computers will have different hardware structure and programming models to which software must adapt. This paper provides an informal discussion on the ways in which changes in high-performance computing architecture will profoundly affect the scalability of our current generation of scientific visualization and analysis codes and how we must adapt our applications, workflows, and attitudes to continue our success at exascale computing.
Postpollination Selection and Male Fitness in Plants

Postpollination events are often described as potential mechanisms for sexual selection in plants. The broadest interpretation of what constitutes sexual selection includes selection on both pollen (analogous to sperm competition in animals) and embryos as possible manifestations of male-male competition and/or female choice. Including selective embryo abortion as a mechanism for sexual selection is controversial because interactions among young progeny and their maternal parent are distinct from interactions among parental plants or their gametes. Nonetheless, I discuss mechanisms for both pre- and postfertilization selection, in part because of the practical difficulties of discriminating between the two. I focus on whether these processes result in differential mating success among pollen donors in natural populations. Evolutionary change occurs when such differences are due to traits controlled by additive genetic variation. Little evidence suggests that postpollination mechanisms affect male reproduc...
Myelin Proteolipid Protein Gene Expression in Jimpy and Jimpymsd Mice

Proteolipid protein (PLP) gene expression was studied in the dysmyelinating mouse mutant jimpy(msd) (jpmsd; myelin synthesis deficient) and compared with that in wild-type mice and the allelic mutant, jimpy (jp). Southern analyses of genomic DNA from jpmsd mice revealed no major rearrangements of the PLP gene relative to the wild-type mouse PLP gene. PLP-specific mRNA levels were significantly reduced in these mutant mice, although both the 3.2- and 2.4-kilobase PLP-specific mRNAs were seen. Also, no size differences in either PLP or DM20 mRNAs were found by S1 nuclease assays of brain RNA from either jpmsd or wild-type mice. Both PLP and DM20 protein were detectable at low levels in jpmsd brain homogenates, and these proteins comigrated with PLP and DM20 protein from normal mice. Western analyses showed an altered PLP:DM20 ratio in jpmsd mice relative to wild-type mice; DM20 levels exceeded PLP levels. It is surprising that a similar pattern of expression was seen in normal mice at less than 10 days of age: DM20 protein expression preceding PLP expression. Thus, jpmsd mice are capable of synthesizing normal PLP and DM20 protein; however, the PLP gene defect has affected the normal developmental pattern of expression for these two proteins.
Gamow-Teller strength function for /sup 90/Zr: Effects of spin and isospin exchange forces, and ground-state correlations

Shell-model calculations of the Gamow-Teller strength function for $^{90}\mathrm{Zr}$ have been performed utilizing a realistic finite-range two-body interaction in a model space consisting of the $2p$ and $1g$ shells. The effects of admixtures of two-particle two-hole excitations in $^{90}\mathrm{Nb}$, mostly due to the spin and isospin exchange components of the nucleon-nucleon force, are discussed. Ground state correlations in $^{90}\mathrm{Zr}$ are also added via seniority-zero two-proton excitations from the $2p$ shell into the $1{g}_{\frac{9}{2}}$ shell. With the correlations the Gamow-Teller strength function is in good agreement with the experimental results and accounts for essentially all of the observed dispersion of strength. The inclusion of these correlations does not, however, produce either a displacement of Gamow-Teller strength to higher excitation energies, or a significant change in the total strength. Thus, they cannot account for the observed Gamow-Teller quenching. The quenching factor derived by a comparison of our calculated results with experiment is 0.52.
Helios target positioning system

The Los Alamos Scientific Laboratory Helios laser fusion system focuses eight powerful CO2 laser beams onto a tiny (typical 300-μm-diam) DT-filled target. The focusing is accomplished inside a vacuum chamber that is 3.5 m in diameter by 3.5 m high. The target positioning system places the target to within 5.0 μm of a predetermined point in space. This is accomplished by using two orthogonal autocollimating telescopes to determine the center of a precisely located surrogate sphere. The target is then placed at the common focal point of the two telescopes. The Helios target positioning system has been meeting or exceeding its design requirements for about one year with minimal maintenance. It has proven to be a very effective system.
β-1,3-Glucanase of Sea Urchin Eggs: Release from Particles at Fertilization

beta-1,3-Glucanase is a latent enzyme found in large and small particles in unfertilized eggs. At fertilization, the enzyme in the large particles is released into the surrounding perivitelline space. The enzyme may be involved in transformations of extracellular glycoproteins.
The effects of nerve growth factor antiserum on ambystoma

Des injections d'un serum specifique contre le facteur de croissance nerveuse (anti-NGF) provoquent une reduction de la taille des ganglions rachidiens de la salamandreAmbystoma par suite de la reduction de la masse cellulaire du ganglion. Il y a aussi un plus grand nombre de «petites» cellules (d'un diametre nucleaire de moins de 6,25 μ) dans les ganglions des animaux utilises.
Using Candy to Teach Counselors to Teach Clients About Medication Compliance

Schizophrenia and other serious mental illness hinder medication compliance. Clinicians are often challenged to increase clients' medication compliance, but lack the tools to enhance consistent treatment compliance. Counselor educators enhance their course instruction by offering a specific counseling tool to students. Those working directly with clients can also use the tool to work with clients to increase medication compliance, thus improving treatment outcome. The role of family in medication compliance is discussed.
The convergence of Cesaro averages for certain nonstationary Markov chains

Abstract If P is a stochastic matrix corresponding to a stationary, irreducible, positive persistent Markov chain of period d >1, the powers P n will not converge as n → ∞. However, the subsequences P nd+k for k =0,1,... d -1, and hence Cesaro averages Σ n k -1 P k / n , will converge. In this paper we determine classes of nonstationary Markov chains for which the analogous subsequences and/or Cesaro averages converge and consider the rates of convergence. The results obtained are then applied to the analysis of expected average cost.
Interactions between Pairs of Charges Buried in the Hydrophobic Interior of a Protein are Unexpectedly Weak

Internal ion pairs buried in the hydrophobic protein interior are essential for many important biochemical processes, including H+ transport, e- transfer, ion homeostasis, and catalysis. Despite the importance of these pairs, their properties remain poorly understood. It has been suggested that, for some systems, medium or long-range Coulomb interactions between buried groups could play a role in determining biological function. In principle, this should only be possible if the protein interior behaves like a medium of low dielectric constant, as assumed in most electrostatics models. These motifs are then of special interest not only for their functional roles, but also as probes to examine the balance between Coulomb and hydration energies experienced by buried charges. As the distance between the internal charges increases, the balance of these energies will disfavor burying the groups in the charged state, eliminating any Coulomb interaction between them. To examine the balance between Coulomb and dehydration energies in the protein interior we engineered a series of double variants in a highly stable variant of staphylococcal nuclease. Each variant included an internal histidine paired with either an aspartate or glutamate buried at various internal positions throughout the protein interior. This set of proteins used to probe the distance dependence of potential Coulomb interactions. No significant electrostatic coupling was observed for pairs that interacted through medium- or long-range Coulomb interactions. When the distance between the groups was short, favorable coupling energies were only observed when the side chains of the pair could achieve a geometry favorable for a H-bond; spatial proximity alone was insufficient to create favorable Coulomb interactions. Simple electrostatics models that describe ionized states as point charges interacting through space are unlikely to be able to reproduce these data.
A validation and extension of a multidimensional ethics scale

Reidenbach and Robin (1988, 1990) proposed and refined a multidimensional ethics scale. This study replicates and extends their work by examining the generalizability of the scale beyond marketing to accounting, and to subjects from across the United States and other countries. Results indicate that, in general, the scale holds for this different sample and context. However, an additional utilitarian construct emerged in the current study as important for accounting academics in their ethical decision-making. We also found that when we refined Reidenbach and Robin's measure of intention to make a particular choice, a social desirability bias or “halo effect” was identified. Methodological implications for business ethics research are also presented.
Phase Properties of Carbon-Supported Gold−Platinum Nanoparticles with Different Bimetallic Compositions

The ability to control the composition and phase properties of bimetallic nanoparticles is critical in exploring catalytic properties. In this paper we present results from a study aimed at determining those properties for carbon-supported gold−platinum (AuPt) catalysts with different bimetallic compositions. The bimetallic nanoparticle catalysts are prepared by a two-phase synthesis protocol employing organic monolayer encapsulation on bimetallic AuPt cores (∼2 nm). The size-controlled nanoparticles are assembled on carbon black support materials with controllable dispersion and metal loading and are further treated by calcination under controlled temperature and atmosphere. The core composition of the bimetallic nanoparticles is determined by direct current plasma-atomic emission spectroscopy. Structural characterization is carried out by X-ray diffraction. The bimetallic nanoparticles were shown to display alloy properties, which is in sharp contrast to the bimetallic miscibility gap known for the bulk...
The distribution of Pb, Ag, Sn, Tl, and Zn in sediments on active oceanic ridges

Abstract Ninety-five sediment samples, taken from traverses across active oceanic ridges, were analyzed by emission spectrography for Pb, Ag, Sn, Tl, and Zn. The concentration patterns produced from these analyses indicate that processes associated with active oceanic ridges partially affect the distribution of Pb, Tl, and Zn, while the distribution of Ag is affected only in the Pacific and western Indian Ocean, and Sn distribution is not related to any active ridge process. The covariation between distance from a ridge and concentration indicates that the ridge effects are not more than 10%. Average concentrations (weighted by sedimentation rates) were determined for Pb, Ag, Sn, Tl, and Zn in parts of the Pacific, the Atlantic, and the Indian Ocean. On the basis of the high elemental concentrations of Pb, Tl, and Zn in the Pacific, the intermediate concentrations in the Indian Ocean, and the low concentrations in the Atlantic, it is inferred that the East Pacific-Antarctic Ridge system is the most active, the north Mid-Atlantic Ridge is the least active, and the Indian Ocean Ridge system is of intermediate activity; all of which seems to be in accord with presently available geophysical data for the same regions.
Empirical Examination of the Corpus Christi Unemployment Rate and Hurricane Bret

A time series econometric model of the Corpus Christi unemployment rate is estimated that includes an intervention variable to capture the impact and recovery activity associated with hurricane Bret in August 1999. The results suggest that Corpus Christi’s labor market improved following the hurricane, controlling for business cycle trends and general movements in the economy.
Targeted approach to identify genetic loci associated with evolved dioxin tolerance in Atlantic Killifish (Fundulus heteroclitus)

The most toxic aromatic hydrocarbon pollutants are categorized as dioxin-like compounds (DLCs) to which extreme tolerance has evolved independently and contemporaneously in (at least) four populations of Atlantic killifish (Fundulus heteroclitus). Surprisingly, the magnitude and phenotype of DLC tolerance is similar among these killifish populations that have adapted to varied, but highly aromatic hydrocarbon-contaminated urban/industrialized estuaries of the US Atlantic coast. Multiple tolerant and neighboring sensitive killifish populations were compared with the expectation that genetic loci associated with DLC tolerance would be revealed. Since the aryl hydrocarbon receptor (AHR) pathway partly or fully mediates DLC toxicity in vertebrates, single nucleotide polymorphisms (SNPs) from 42 genes associated with the AHR pathway were identified to serve as targeted markers. Wild fish (N = 36/37) from four highly tolerant killifish populations and four nearby sensitive populations were genotyped using 59 SNP markers. Similar to other killifish population genetic analyses, strong genetic differentiation among populations was detected, consistent with isolation by distance models. When DLC-sensitive populations were pooled and compared to pooled DLC-tolerant populations, multi-locus analyses did not distinguish the two groups. However, pairwise comparisons of nearby tolerant and sensitive populations revealed high differentiation among sensitive and tolerant populations at these specific loci: AHR 1 and 2, cathepsin Z, the cytochrome P450s (CYP1A and 3A30), and the NADH dehydrogenase subunits. In addition, significant shifts in minor allele frequency were observed at AHR2 and CYP1A loci across most sensitive/tolerant pairs, but only AHR2 exhibited shifts in the same direction across all pairs. The observed differences in allelic composition at the AHR2 and CYP1A SNP loci were identified as significant among paired sensitive/tolerant populations of Atlantic killifish with multiple statistical tests. The genetic patterns reported here lend support to the argument that AHR2 and CYP1A play a role in the adaptive response to extreme DLC contamination. Additional functional assays are required to isolate the exact mechanism of DLC tolerance.
Photodissociation of HCl+/MgO(001): The static and dynamic effects of the surface

The photodissociation dynamics of surface‐adsorbed HCl+ is studied using both time‐dependent and time‐independent quantum mechanical methods. The photodissociation line shapes and photofragment angular distributions are calculated following excitation to the (2)2Σ and the (2)2Π electronic states, correlating with Cl++H and with Cl+H+, respectively. Complementary insight is gained by analyzing also the classical photodissociation dynamics. We find pronounced shifts and modifications of the photodissociation line shapes, which depend sensitively on the fragmentation channel and reflect surface‐induced modification of the adsorbed state and the excited HCl+ potential energy surfaces. The quantum mechanical angular distributions exhibit a rich, energy‐dependent structure, which differs substantially for the two fragmentation channels. Assisted by the classical trajectory results, we ascribe the structure to surface‐induced rainbow scattering. The sensitivity of the photodissociation line shape and the angular...
Multiple ependymomas in a patient with Turcot's syndrome

A 21-year-old woman was diagnosed with Turcot's syndrome (TS) at age 16 years. She had two ependymomas, one was located in the left middle cerebellar peduncle and the other in the low sacral spinal canal. Her mother and brother both had colectomies for colonic polyposis. Her maternal uncle and grandfather also had this disease and both died from cancer of the colon in their fourth decade of life. The patient was found to have hyperpigmented spots in the retina, skull osteomas and normal neurological examinations. The bone scan and CSF were normal and she had a germline mutation in the segment 3 of the adenomatous polyposis coli (APC) gene. Following partial resection of the two ependymomas, she was treated with radiation and chemotherapy. One year after surgery, paraspinal desmoid tumors were found and removed. She is presently 42 months postsurgical resection of the neural tumors and has remained central nervous system tumor-free. The occurrence of multiple ependymoma in TS has not been reported, and the control of this patient's ependymomas is consistent with other reports of long-term survival with TS and glial tumors. © 1997 Wiley-Liss, Inc.
Decentralized path planning for multi-agent teams in complex environments using rapidly-exploring random trees

This paper presents a novel approach to address the challenge of planning paths for multi-agent systems operating in complex environments. The algorithm developed, Decentralized Multi-Agent Rapidly-exploring Random Tree (DMA-RRT), is an extension of the Closed-loop RRT (CL-RRT) algorithm to the multi-agent case, retaining its ability to plan quickly even with complex constraints. Moreover, a merit-based token passing coordination strategy is developed to dynamically update the planning order based on a measure of each agent's incentive to replan, derived from the CL-RRT. Agents with a greater incentive plan sooner, yielding a greater reduction of the global cost and greater improvement in the team's overall performance. An extended version of the algorithm, Cooperative DMA-RRT, allows agents to modify others' plans in order to select paths that reduce their combined cost and thus further improve global performance. The paths generated by both algorithms are proven to satisfy inter-agent constraints, such as collision avoidance, and a set of simulation and experimental results verify performance.
SU-E-T-115: A Novel Cylindrical 3D Water Scanner for Beam Data Collection: II. Dosimetric Characteristics.

Purpose: To study the dosimetric characteristics of a commercial three‐dimensional water scanner (3D SCANNER, Sun Nuclear Corp). The novel cylindrical scanner uses a compact electrometer mounted on the side of the tank, eliminating the need for chamber extension cables. The electrometer has a wide dynamic range, requiring no gain adjustment as scanning conditions change, e.g., field size, dose rate, wedge field, etc. Methods: Measurements from the 3D SCANNER were compared against those from another commercial scanner (Blue Phantom, IBA Dosimetry). Comparable collection intervals and scanning speeds were used on both systems. Profile and depth measurements were performed for open field beams (6 and 18 MV; 10‐cm and 30‐cm squared fields; depths of dmax, 10, and 30 cm) and wedged fields (6 and 18 MV; 30‐cm squared field; depth of 10 cm). Electron beam profile and depth measurements were performed for a 20‐cm squared applicator (6, 12, and 20 MeV; depth of dmax). The root mean square (RMS) values were determined for each scanner'smeasurements.Results: The measuredfield sizes were within 0.06 cm and 0.05 cm for photon and electron beams, respectively. The photon D10/D20 ratios differed by < 0.4% and the electron I50 values were within 0.02 cm. The RMS of the profiles was approximately 0.1% for both the 3D SCANNER and Blue Phantom measurements. Between the two scanners, all measurements agreed within RMS, excluding the penumbra region. Two exceptions occurred: a 0.5% difference was observed in the shoulder of the 12 MeV profiles, and a 0.8% difference was observed in the 6 MeV depth measurements near the surface.Conclusions: The quality of the scanned profile and depth measurements from the 3D SCANNER is comparable to that of another commercial scanner. Both scanning systems have similar levels of scanning noise. This work was partially supported by a research grant from Sun Nuclear Corp., Melbourne, FL
Divide the Dollar: Three solutions and extensions

Divide the Dollar (DD) is a game in which two players independently bid up to 100 cents for a dollar. Each player receives his or her bid if the sum of the bids does not exceed a dollar; otherwise they receive nothing. This game has multiple Nash equilibria, including the egalitarian division of (50, 50), but this division is not compelling except for its symmetry and presumed fairness.
Three-dimensional calcification reconstruction from a limited number of views

A method has been developed to allow mammographic differential diagnosis based upon the 3- D orientation and morphology of mammary calcifications. Two to seven digital radiographs of a cluster of calcifications are acquired on a prone stereotactic breast biopsy system. The images are segmented using a recursive region-growing algorithm. Inclusion of calcific material is dependent upon local statistics calculated over a region surrounding each calcification. Segmentation is aided by correlation of the calcifications in two or more views through analysis of their positions, sizes and shapes. The location of each calcification is determined geometrically; the shape of each calcification is calculated using the segmented images and a simulated annealing reconstruction method. Image segmentation and reconstruction can be reproducibly performed with an accuracy of 0.1 mm, which is sufficient to perform 3-D morphologic analysis. Biopsy specimens and in vivo calcifications have been examined. In instances where calcifications are associated with amass, we can distinguish preferentially peripherally distributed calcifications from homogeneously distributed calcifications. We have also been able to elucidate the linear distribution of calcifications contained within the ductal system. In a preliminary ROC study involving 3 radiologists and 26 lesions (5 malignant), specificity increased when 3-D images were included in the diagnostic evaluation, resulting in an increase of Az from 0.66 to 0.88 (p equals 0.0039).© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Does satiation close the open economy

Pigeons responded on fixed-interval and fixed-ratio food schedules during sessions of extended duration. Pause lengths from the beginning of the session, when the subjects were hungry, resembled those found in open economies, whereas pause lengths from the end of the sessions, when the subjects were close to satiation, resembled those from closed economies. A model of motivation captured key features of the data, suggesting that a changing level of hunger is a causal factor in the behavioral differences observed between open and closed economies. Behavioral theories may provide a parsimonious alternative to economic theories in accounting for such effects.
IRON ABSORPTION BY BILATERALLY NEPHRECTOMIZED RATS.

SummaryIron absorption as measured by tissue radioactivity is impaired in bilaterally nephrectomized rats. These animals still show increased absorption, however, when subjected to reduced atmospheric pressure or oxygen tension, a situation very similar to that seen with hypophysectomized animals.
A reexamination of the single scattering approximation

With the increasing speed of computers and the development of more sophisticated numerical methods, complex electromagnetic problems are being attacked and solved. Yet with this advance, there is the ever present pitfall of losing sight of the fundamental physics involved in the problem. In fact in many cases it may be advisable to use a less accurate approximate solution to get a better understanding of the fundamental interactions involved in the problem. With this as a background, this paper will examine the so-called single scattering or local approximation that is frequently used in very complex problems that can be described by boundary integral equations of the second kind. The single scattering or local approximation amounts to assuming that the unknown current, say, at a point on a rough surface is not dependent upon the current at any other point on the surface. While this is a very simple definition, it is not always easy to pull the single scattering solution out of a second boundary integral equation. For example, in rough surface scattering from the perfectly conducting surface, the Kirchhoff approximation is frequently taken as the single scattering solution and this does work very well for a class of surfaces but not all. However, for another class of surfaces one must employ a boundary perturbation approach to obtain an accurate solution. Interestingly enough this solution obeys the definition of a single scattering or local approximation but seems to require cooperative scattering from two points on the rough surface. In addition, this solution seems to come from the second Neumann iterate of the governing integral equation. This paradox raises the question of what truly is the single scattering or local approximate solution of a second kind boundary integral equation. This difficulty will be addressed through the application of the generalized mean value theorem for integrals as applied to the second kind integral equation. Following the application of this theorem to the second kind integral equation, we show that the local approximation leads to an approximate solution of the form J o (x)[1-∫ G(x, x′)dx′]−1 where J o (x) is the Kirchhoff term and G(x, x″) is the propagator or kernel in the integral equation. We will discuss this solution and our statement that this is the single scattering solution. In addition we will consider what happens when an attempt is made to apply the logic developed herein to a preconditioned form of the second kind integral equation such as with the Method of Ordered Multiple Interactions (MOMI). Some attention will be devoted to how one might improve on this true single scattering solution and a physical consequence of the mathematical condition that the kernel G(x, x′) be a positive quantity.
Finite deformation plasticity based on the additive split of the rate of deformation and hyperelasticity

Abstract Finite deformation plasticity formulation based on additive split of rate of deformation and hyperelasticity is presented. This approach is valid for finite elastic and plastic strains, while rendering the choice and numerical integration of objective stress rates superfluous as the results are automatically objective. For small elastic strains our method reduces to the classical hypoelastic-corotational formulation provided that the Dienes objective stress rate is employed, while in the absence of inelastic deformation it coincides with the hyper-elastic formulation. The validity of the model has been examined on four test problems and the numerical results were found to be in good agreement with either the exact solution or experimental data.
The adsorption of ammonia on zirconium surfaces: effect of adsorption temperature on the thermal desorption of water

Abstract Ammonia adsorption on Zr(0 0 0 1) under ultra-high vacuum conditions has been studied using temperature programmed desorption (TPD) and low energy electron diffraction (LEED) methods. Data from TPD measurements indicate that water accompanies the thermal desorption of ammonia and that relative yields and desorption profiles depend on adsorption temperature. Subsequent to desorption, recovery of clean-surface LEED patterns requires various amounts of sputtering and annealing depending on adsorption conditions. The implications are that ammonia dissociation occurs in this system leaving residual nitrogen at or near the surface and that the formation of water may involve oxygen from the bulk.
An estrogen-dependent four-gene micronet regulating social recognition: A study with oxytocin and estrogen receptor-α and -β knockout mice

Estrogens control many physiological and behavioral processes, some of which are connected to reproduction. These include sexual and other social behaviors. Here we implicate four gene products in a micronet required for mammalian social recognition, through which an individual learns to recognize other individuals. Female mice whose genes for the neuropeptide oxytocin (OT) or the estrogen receptor (ER)-β or ER-α had been selectively “knocked out” were deficient specifically in social recognition and social anxiety. There was a remarkable parallelism among results from three separate gene knockouts. The data strongly suggest the involvement in social recognition of the four genes coding for ER-α, ER-β, OT, and the OT receptor. We thus propose here a four-gene micronet, which links hypothalamic and limbic forebrain neurons in the estrogen control over the OT regulation of social recognition. In our model, estrogens act on the OT system at two levels: through ER-β, they regulate the production of OT in the hypothalamic paraventricular nucleus, and through ER-α, they drive the transcription of the OT receptor in the amygdala. The proper operation of a social recognition mechanism allows for the expression of appropriate social behaviors, aggressive or affiliative.
Diffusion maps for PLDA-based speaker verification

During the last few years, i-vectors have become an important component in most state-of-the-art speaker recognition systems. I-vector extraction is based on an assumption that GMM supervectors reside on a low dimensional space, which is modeled using Factor Analysis. In this paper we replace the above assumption with an assumption that the GMM supervectors reside on a low dimensional manifold and propose to use Diffusion Maps to learn that manifold. The learnt manifold implies a mapping of spoken sessions into a modified i-vector space which we call d-vector space. D-vectors can further be processed using standard techniques such as LDA, WCCN, cosine distance scoring or Probabilistic Linear Discriminant Analysis (PLDA). We demonstrate the usefulness of our approach on the telephone core conditions of NIST 2010, and obtain significant error reduction.
5-Methylthioribose kinase activity in plants.

Abstract The presence of a previously unidentified plant enzyme, 5-methylthioribose kinase, has been demonstrated to exist in cell-free extracts from several fruit tissues. The enzyme catalyzes the ATP-dependent phosphorylation of 5-methylthioribose to 5-methylthioribose-1-phosphate. Enzyme activity has been found in avocado, pear, apple, strawberry and tomato tissues. The significance of the presence of this enzyme in relation to ethylene biosynthesis is discussed.
Low molecular mass GTP-binding proteins are secreted from mammary epithelial cells in association with lipid globules.

Abstract Secretion of milk lipid globules is achieved through encapsulation of triacylglycerol-rich lipid droplets in a specialized region of apical plasma membrane of mammary epithelial cells. A class of low molecular mass GTP-binding proteins were associated tightly with the lipid globule membrane, and these proteins appeared to change from peripheral to integral membrane proteins during intracellular growth and transit of lipid globule precursors. Inclusion of GTP or GTPγS in incubation medium stimulated secretion of lipids from primary cultures of permeabilized rat mammary epithelial cells. Six polypeptides with molecular masses between 28 and 21 kDa were detected by ability to bind GTPγS following separation of lipid-globule-associated proteins by SDS-PAGE and transblotting onto nitrocellulose. That all of these polypeptides were distinct immunologically from the archetype ras was evident from lack of immunoreactivity with p21ras G-protein monoclonal antibody in Western blots. This monoclonal antibody bound to a 23 kDa polypeptide of lipid droplets that was not detected with the GTPγS binding assay. A 25 kDa component of milk lipid globules was a potent substrate for ADP-ribosylation by botulinum toxin C3, but cholera toxin was much less effective, suggesting that this component may belong to the rac class of G-proteins. The 21 kDa component was related immunologically to ADP ribosylation factor.
Computer-aided macroergonomics for improved performance and safety

The U.S. presidential election of 2000 was characterized by alleged ergonomic problems associated with the design of voting ballots. However, this visible event actually exemplified the fact that many apparent ergonomic issues are, in fact, macroergonomic issues. That is, in such cases, there are larger systemic factors at work that interact with and contribute to human–machine interface issues. Further complicating system effectiveness is the notion that modern work systems are distributed and therefore require computer aiding to establish a communication pipeline through which decisions can flow and performance can be enhanced. A conceptual and theoretical framework is presented for understanding such computer-aided work systems and a taxonomy and research examples for three types of computer-aided work systems are also offered. It is concluded that the single operator–single machine paradigm is not obsolete and the focus remains ultimately on the ergonomic level, but relevant macroergonomic, sociotechnical system factors require consideration prior to optimizing this level for overall ergonomic success. © 2002 Wiley Periodicals, Inc.
Role of DLC-1, a tumor suppressor protein with RhoGAP activity, in regulation of the cytoskeleton and cell motility

DLC-1 was originally identified as a potential tumor suppressor. One of the key biochemical functions of DLC-1 is to serve as a GTPase activating protein (GAP) for members of the Rho family of GTPases, particularly Rho A-C and Cdc 42. Since these GTPases are critically involved in regulation of the cytoskeleton and cell migration, it seems clear that DLC-1 will also influence these processes. In this review we examine basic aspects of the actin cyoskeleton and how it relates to cell motility. We then delineate the characteristics of DLC-1 and other members of its family, and describe how they may have multiple effects on the regulation of cell polarity, actin organization, and cell migration.
Two‐ and Three‐Dimensional Transthoracic Echocardiography in the Assessment of Aortic Arch Vasum Vasi to Pulmonary Artery Fistula

We report an elderly patient presenting with a stroke and also hemolytic anemia secondary to mitral and tricuspid valve repair 3 years earlier, in whom two-dimensional transesophageal echocardiography (2DTEE) suspected a fistula into the pulmonary artery (APAF) from the posterior wall of the aortic arch. For further assessment, two-dimensional transthoracic echocardiography (2DTTE) and live/real time three-dimensional transthoracic echocardiography (3DTTE) were performed. 2DTTE showed findings similar to 2DTEE. Color Doppler guided continuous-wave Doppler showed continuous flow throughout the cardiac cycle with systolic preponderance across the fistula with a small peak pressure gradient of 22 mmHg. Sequential systematic cropping of the 3D datasets obtained from 3DTTE confirmed that the flow signals originated from the posterior wall of the aortic arch and not the lumen. Thus, 3DTTE served to increase the confidence level that the fistula most likely originated from a vasum vasi in the wall of the aortic arch. To our knowledge, this type of fistula has not been reported previously. Fistulas from the aortic lumen to the pulmonary artery are also rare and so far only 24 cases have been reported in the literature. These are also reviewed by us.
Closed-loop artificial pancreas using subcutaneous glucose sensing and insulin delivery and a model predictive control algorithm: the Virginia experience.

Background:Recent progress in the development of clinically accurate continuous glucose monitors (CGMs), automated continuous insulin infusion pumps, and control algorithms for calculating insulin doses from CGM data have enabled the development of prototypes of subcutaneous closed-loop systems for controlling blood glucose (BG) levels in type 1 diabetes. The use of a new personalized model predictive control (MPC) algorithm to determine insulin doses to achieve and maintain BG levels between 70 and 140 mg/dl overnight and to control postprandial BG levels is presented.Methods:Eight adults with type 1 diabetes were studied twice, once using their personal open-loop systems to control BG overnight and for 4 h following a standardized meal and once using a closed-loop system that utilizes the MPC algorithm to control BG overnight and for 4 h following a standardized meal. Average BG levels, percentage of time within BG target of 70–140 mg/dl, number of hypoglycemia episodes, and postprandial BG excursions d...
DEc users’ group report

DEC users discussed ways to improve communications among users, including the initiation of a newsletter. Also, new products of special interest to psychologists were described by the DEC representative present at the meeting.
Perspectives from ethnography on weak and strong reciprocity

To add ethnographic perspective to Guala's arguments, I suggest reasons why experimental and ethnographic evidence do not concur and highlight some difficulties in measuring whether positive and negative reciprocity are indeed costly. I suggest that institutions to reduce the costs of maintaining cooperation are not limited to complex societies.
Pediatric head injury: a further experience.

This report consists of 201 patients seen at the Medical College of Virginia from May 1976 to October 1991. They are divided into two groups. The first group is from May 1976 to June 1984 and the seco
Accuracy and Power of the Likelihood Ratio Test for Comparing Evolutionary Rates Among Genes

Sequences for multiple protein-coding genes are now commonly available from several, of- ten closely related species. These data sets offer intriguing opportunities to test hypotheses regarding whether different types of genes evolve under differ- ent selective pressures. Although maximum likeli- hood (ML) models of codon substitution that are suitable for such analyses have been developed, little is known about the statistical properties of these tests. We use a previously developed fixed-sites model and computer simulations to examine the accuracy and power of the likelihood ratio test (LRT) in comparing the nonsynonymous-to-synonymous substitution rate ratio (x = dN/dS) between two genes. Our results show that the LRT applied to fixed-sites models may be inaccurate in some cases when setting significance thresholds using a v 2 approximation. Instead, we use a parametric bootstrap to describe the distribution of the LRT statistic for fixed-sites models and examine the power of the test as a function of sampling vari- ables and properties of the genes under study. We find that the power of the test is high (>80%) even when sampling few taxa (e.g., six species) if sequences are sufficiently diverged and the test is largely unaf- fected by the tree topology used to simulate data. Our simulations show fixed-sites models are suitable for comparing substitution parameters among genes evolving under even strong evolutionary constraint (x 0.05), although relative rate differences of 25% or less may be difficult to detect.
Epidemiology of Knee and Hip Arthroplasty: A Systematic Review

We present a systematic review of epidemiologic studies of Total Knee Arthroplasty (TKA) and Total Hip Arthroplasty (THA). The studies summarized in this systematic review provide us with estimates of arthroplasty utilization rates, underlying disease frequency and its trends and differences in utilization rates by age, gender and ethnicity among other factors. Among these, many studies are registry-based that assessed utilization rates using data from major orthopedic centers that may provide some understanding of underlying diagnosis and possibly time-trends. Several studies are population-based cross-sectional, which provide estimates of prevalence of TKA and THA. Population-based cohort studies included in this review provide the best estimates of incidence and utilization rates, time-trends and differences in these rates by important patient characteristics (age, gender, ethnicity and others). This article reviews the current published literature in the area and highlights the main findings.
A probabilistic model for correcting the directional sensitivity of optical probe measurements

A probabilistic model is introduced for correcting the directional sensitivity of the optical probe technique routinely used to determine gas holdup and bubble dynamics in gas-liquid systems. Measurements from optical probes oriented at various angles were collected from the tapered end of optical probes in regions where approximately unidirectional and bubbly flow conditions were observed. Based on logical assumptions, constitutive equations for a probabilistic model were formulated, and contributions to the overall local gas phase holdup from bubbles traveling in two opposite directions were quantified. The results demonstrate a novel and useful way to interpret optical probe measurements. © 2015 American Institute of Chemical Engineers AIChE J, 61: 3516–3527, 2015