cssi/SciSciGPT-SciSciNet huggingface dataset:
What's in a Prerequisite

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Regulation of Postnatal Expression of the α, β, and γ Subunits of the Amiloride-Sensitive Sodium Channel in Rat Lung by Dexamethasone † 1502

Amiloride-sensitive epithelial sodium channels (ENaC) are the major pathway for efflux of sodium from the alveolar lumen. The functional activity of these channels modulates the volume and composition of the alveolar subphase, and is essential to the perinatal clearance of fetal lung liquid. The channels are composed of three subunits (α, β, and γ), each encoded by a distinct mRNA transcript. Adminstration of dexamethasone prenatally has been shown to increase expression of the α subunit in fetal distal lung epithelium. We investigated the postnatal effects of dexamethasone administration on the expression of each of the ENaC subunits. Timed pregnant Sprague-Dawley rats were administered dexamethasone 4 mg/kg IP (or carrier) daily from gestational age 18 to 21. Rats were allowed to deliver and ENaC expression determined at various postnatal timepoints by Northern blot analysis of total lung RNA. Blots were hybridized with cRNA probes for each of the channel subunits and signal quantified by phosporimagery after normalization to GAPDH. Expression of all three ENaC subunits was increased relative to control the first postnatal day. By the third postnatal day no difference in expression between control and treated animals was detected. We subsequently investigated the effect of postnatal adminstration of dexamethasone to newborn rats on lung ENaC expression. Rat pups at various ages received dexamethasone 2 mg/kg IP (or carrier) and were sacrificed 24 h later. An age-dependent effect of dexamethasone on ENaC expression was observed. Maximal effect was observed in 1week old pups, with an 4.5 fold increase in the α and a 2.5 fold increase in the β and γ subunits relative to control. Little effect was observed in mature animals. In situ hybridization with a digoxigenin labeled probe for theα subunit localized expression to the conductive airway epithelium and type II pneumocytes. Cultured type II pneumocytes demonstrated a dose (0.001 to 0.1 μM) and time (0-24 h) dependent increase in expression of each subunit in response to dexamethasone in vitro. These data demonstrate that pulmonary expression of all three subunits of the ENaC is regulable by postnatal glucocorticoid administration.
Are we meeting ACGME core competencies? A systematic review of literature on international surgical rotations

Abstract Background In response to the growing interest in global surgery among trainees, international surgical rotation (ISR) was approved as a formal elective of resident curriculum. To define ISR's role, we aim to identify the six core competencies of Accreditation Council for Graduate Medical Education (ACGME) in individual institution's experience. Data sources This is a systematic literature review studying general surgery resident experience in ISR as it pertains to the ACGME core competencies. Articles were searched using PubMed, Scopus, and Web of Science. Each abstract and article was reviewed, selected, and tabulated. Conclusion Fourteen articles were selected for the review after inclusion and exclusion criteria were applied. We found that ISR provided a valuable educational experience for US surgical residents by meeting the ACGME core competencies in a different environment. ISR is an important addition to the general surgery curriculum. Future direction should focus on bidirectional ISR and educational consortium development.
A Study on the Impact of Channel Mobility on Switching Performance of Vertical GaN MOSFETs

This paper presents a comparison of switching performances between the in-situ oxide, gallium nitride (GaN) interlayer FET (OG-FET) and the conventional GaN metal–oxide–semiconductor FET (MOSFET), and explores the influence of the channel electron mobility on the device switching performance. GaN OG-FET is a novel structure with a pristine GaN layer grown between the gate oxide and the p-GaN enhancing the channel mobility up to 185 cm2/ $\text {V}\cdot \text {s}$ , which is over $3{\times}$ larger than that of the typical reported value (50 cm2/ $\text {V}\cdot \text {s}$ ) in GaN MOSFET. Owing to the high channel electron mobility, the GaN OG-FET showed a switching loss 30% lower than that of the conventional GaN trench MOSFET. Our results indicate that GaN OG-FET has the potential to attain greater efficiency, particularly at higher frequencies, showing a possible patch toward megahertz range conversions.
Lichttherapie niet alleen voor winterdepressie

Lichttherapie is een reguliere behandeling van winterdepressie. De laatste jaren is er ook veel onderzoek gedaan naar de effecten van lichttherapie bij diverse andere stemmingsstoornissen. Deze CAT laat zien dat lichttherapie ook bij niet-seizoensgebonden depressie effectief kan zijn en veilig kan worden toegepast. Het bewijs daarvoor is weliswaar beperkt, maar de bijwerkingen zijn mild. Daarom is lichttherapie bij depressie in elk geval te overwegen.
The effect of welfare payments on work: Regression discontinuity evidence from Ecuador

Abstract We study the impact of welfare payments in Ecuador on the probability that adults work, and on whether they are employed in the formal or informal sectors. Our identification strategy exploits the fact that welfare was limited to individuals below a cutoff value on a household “poverty score”. We find no evidence that transfers discouraged work. However, among women, welfare payments led to reductions in social security contributions (which are mandated for salaried workers), although the magnitude of these effects is small.
Instantaneous and Equilibrium Responses of the Brain Tissue by Stress Relaxation and Quasi-Linear Viscoelasticity Theory

Human brain and brainstem tissues have viscoelastic characteristics and their behaviours are functions of strains, as well as strain rates. Determination of the equilibrium and instantaneous stresses happening at low and high strain rates provide insights into a better understanding of the behaviour of such tissues. In this manuscript we present the results of a series of stress relaxation tests, at six different values of strains conducted on porcine brainstem tissue samples to indirectly measure the equilibrium and instantaneous stresses. The equilibrium stresses at low strain rates are measured from long-term responses of the stress relaxation test. The instantaneous stresses at high strain rates are determined using Quasi-Linear Viscoelasticity (QLV) theory at six strains. The results show that the instantaneous stresses are much larger (almost 11 times) than the equilibrium stresses and across all the strains. It can be concluded that the instantaneous response can be reasonably estimated from the long-term response which can be easily measured experimentally. The experimental results also show that the reduced relaxation moduli, estimated from the QLV theory, vary for the six strains tested.
Evaluating a Tactile Approach to Programming Scratch

Computer Science in K-12 is continuing to become more prevalent. Because learning syntax and debugging can be burdensome, many teachers in K-12 use block languages to teach their students. Block languages, such as Scratch, allow students to focus on simple programming concepts and logic, and therefore, make computer programming easier and more approachable to students. However, block languages are not accessible to students with visual impairments because of block-environments' high dependence on visual aspects. This paper describes an innovative peripheral device that can help students with visual impairments access Scratch by simply remembering six buttons and guided by auditory cues generated by the computer. In order to test CodeBox64's usability and efficiency, a simple user study was conducted. Based on the data collected from the user study, CodeBox64 functioned properly and efficiently.
Jose Marti’s Confederate Affinities

Jose Marti examines the American Civil War and the period of Reconstruction through the lens of Cuba’s failed attempts at independence as a way of disenchanting modernizers and annexationists who, ...
The Circulation and Silence of Weaving Knowledge in Contemporary Navajo Life

This article draws upon ethnographic fieldwork within a Navajo community to illustrate how weaving knowledge and practices shape contemporary notions of community identity and belonging. The ongoing exchange of Navajo weaving taboos and the careful management of weaving teachings offers community members various opportunities to share and keep certain kinds of information in and out of circulation. The flow of such knowledge provides a productive context for community members to voice their ideas and opinions about a range of topics, including concepts of inalienable patrimony, reciprocity, qualities of personhood and prized personal characteristics, and the exchange of knowledge more generally.
Phase diagram of Script N = 4 super-Yang-Mills theory with R-symmetry chemical potentials

The phase diagram of large Nc, weakly-coupled = 4 supersymmetric Yang-Mills theory on a three-sphere with non-zero chemical potentials is examined. In the zero coupling limit, a transition line in the μ-T plane is found, separating a ``confined'' phase in which the Polyakov loop has vanishing expectation value from a ``deconfined'' phase in which this order parameter is non-zero. For non-zero but weak coupling, perturbative methods may be used to construct a dimensionally reduced effective theory valid for sufficiently high temperature. If the maximal chemical potential exceeds a critical value, then the free energy becomes unbounded below and no genuine equilibrium state exists. However, the deconfined plasma phase remains metastable, with a lifetime which grows exponentially with Nc (not Nc2). This metastable phase persists with increasing chemical potential until a phase boundary, analogous to a spinodal decomposition line, is reached. Beyond this point, no long-lived locally stable quasi-equilibrium state exists. The resulting picture for the phase diagram of the weakly coupled theory is compared with results believed to hold in the strongly coupled limit of the theory, based on the AdS/CFT correspondence and the study of charged black hole thermodynamics. The confinement/deconfinement phase transition at weak coupling is in qualitative agreement with the Hawking-Page phase transition in the gravity dual of the strongly coupled theory. The black hole thermodynamic instability line may be the counterpart of the spinodal decomposition phase boundary found at weak coupling, but no black hole tunneling instability, analogous to the instability of the weakly coupled plasma phase is currently known.
Convergence Rates of Simulated Annealing-Type of Recursive Algorithms

This work is concerned with rates of convergence of simulated annealing type of algorithms for Monte Carlo optimization. We derive error bounds for the approximation sequences via the use of perturbed Liapunov function methods, and we show that a suitably scaled sequence converges weakly to a diffusion process.
On computing the nonlinearity interval in parametric semidefinite optimization

This paper revisits the parametric analysis of semidefinite optimization problems with respect to the perturbation of the objective function along a fixed direction. We review the notions of invariancy set, nonlinearity interval, and transition point of the optimal partition, and we investigate their characterizations. We show that the set of transition points is finite and the continuity of the optimal set mapping, on the basis of Painleve-Kuratowski set convergence, might fail on a nonlinearity interval. Under a local nonsingularity condition, we then develop a methodology, stemming from numerical algebraic geometry, to efficiently compute nonlinearity intervals and transition points of the optimal partition. Finally, we support the theoretical results by applying our procedure to some numerical examples.
Iron Binding to Specific Lobes of Transferrin Differentially Affects Erythropoiesis and Hepcidin Signaling

Introduction: Transferrin (Tf) plays a role in iron homeostasis as both an iron cargo molecule and as a signaling molecule. Tf is comprised of two homologous lobes (N and C), each of which can bind one iron molecule. As such Tf circulates as four forms: diferric, monoferric C, monoferric N and apo. Upon iron binding, clefts in each lobe close resulting in a conformational shift in the structure of the molecule and altering its affinity for the transferrin receptors. The most abundant molecules in the circulation at normal transferrin saturations are the monoferric forms. The relative abundance of circulating monoferric N in healthy individuals is greater than C, and greater with increased iron status. The N and C lobes differ in several physical properties, including binding affinities for iron. Whether these differences have functional consequences has been a subject of controversy. In vitro data suggest that iron is released initially from the C-lobe during delivery from diferric Tf to the erythron. These observations led to the proposal that iron occupancy of the N lobe might serve as an indicator of erythroid iron sufficiency, and as a signal to regulate dietary iron absorption. We thus hypothesized that iron homeostasis would be influenced by the presence of iron on the transferrin C-lobe vs the N-lobe. Methods: To test this hypothesis, we generated mice producing exclusively monoferric N or C transferrins by mutating two essential tyrosines in the iron binding site of each of the lobes to phenylalanine (Y114 and Y207 in the N-blocked (N-bl) mouse and Y448 and Y537 in the C-blocked (C-bl) mouse). Heterozygous mice were crossed and offspring analyzed for hematological parameters, tissue iron concentrations, and expression by RT-PCR of selected genes relevant to iron homeostasis. Results: The N-bl and C-bl Tf mutant mice each demonstrate hepatic iron loading; however, N-bl mice demonstrated higher non-heme liver iron concentrations than C-bl Tf mutant mice (1542 +/- 89.48 vs 1089 +/- 110.6 ug Fe/g dry weight, respectively; p Conclusions: N-bl and C-bl Tf mutant mice demonstrate a hemochromatosis phenotype consistent with decreased hepcidin signaling; however, severity differs. Both mouse models demonstrate iron restrictive erythropoiesis; however, erythrocyte count is suppressed relative to erythropoietin levels only in the N-bl mutant mice. The N and C lobes of transferrin thus demonstrate functionally distinct properties. We speculate that iron bound to the N-lobe of transferrin augments the signaling properties of transferrin which regulate hepcidin expression and erythropoiesis. Disclosures Rivella: Ionis Pharmaceuticals: Membership on an entity9s Board of Directors or advisory committees, Research Funding. Fleming: Protagonist Therapeutics: Membership on an entity9s Board of Directors or advisory committees.
Horizontal Transport of Buoyant Material by Turbulent Jets in the Upper Ocean

AbstractCurrents in the ocean surface boundary layer (OSBL) determine the horizontal transport of submerged buoyant material, such as pollutants, plankton, and bubbles. Commonly, the mean horizonta...
The Safety and Clinical Outcomes of Transcatheter Aortic Valve Replacement in a Middle Eastern Population

Objective: Evaluate the clinical characteristics and outcomes of patients with symptomatic, severe AS undergoing TAVR versus SAVR.Methods: We performed a retrospective analysis of all consecutive p...
Techniques for Prenatal Diagnosis

Recent developments in circulating cell-free nuclei acid screening and microarray assays have changed our fundamental approach to prenatal diagnosis, which had been based on relatively crude screening algorithms geared to the detection of fetal chromosomal abnormalities and a limited number of Mendelian disorders. We now see a far more effective approach to screening for common fetal aneuploidies and have begun to change our focus from chromosomal and Mendelian disorders to the expansive number of genomic deletions and duplications, many of which are associated with clearly defined clinical presentations. Regardless of the new advancements being introduced into clinical care, the diagnosis of fetal chromosome and genomic abnormalities is still only achievable by invasive prenatal diagnosis. In this chapter, we present current information on the techniques, effectiveness and safety of amniocentesis and chorionic villus sampling (CVS), as well as other fetal diagnostic procedures that are used less frequently because the advancements of the Human Genome Project have allowed for the diagnosis of an increasing number of conditions by CVS and amniocentesis rather than fetal tissue biopsy. Until a method is developed to reliably obtain fetal cells from maternal blood, invasive prenatal testing will likely remain an integral part of obstetrical care.
Comparative metrics of neurosurgical scientific journals: What do they mean to readers?

Background In regard to scientific information, are we effectively reaching the universe of physicians in the 21st century, all of whom have different backgrounds, practice environments, educational experiences, and varying degrees of research knowledge? Methods A comparison of the top nine neurosurgery journals based on various popular citation indices and also on the digital metric, Readers (Users)/month, was compiled from available metrics and from internet sources. Results Major differences in the ranking of the Readers (Users)/month metrics compared to ranking of the various citation indices were found. It is obvious that the citation indices do not measure the number of readers of a publication. Which metric should be used in judging the value of a scientific paper? The answer to that question relates to what the interest of the reader has in the scientific information. It appears that the academic scientist may have a different reason for reading a scientific publication than a physician caring for a patient. Conclusions There needs to be more than one type of metric that measures the value and "Impact" of a scientific paper based on how physicians learn.
Service needs of children exposed to domestic violence: Qualitative findings from a statewide survey of domestic violence agencies

Abstract Objective Each year, more than 6% of all U.S. children are exposed to domestic violence and require intervention services from agencies that serve affected families. Previous research has examined detrimental biopsychosocial consequences of domestic violence exposure during childhood and the importance of effective prevention and intervention services for this population. However, less research has explored diverse intervention professionals’ own perspectives on the needs of the domestic violence-exposed children they serve. Method This study employed an inductive approach to thematic analysis to investigate intervention professionals’ reflections and advice regarding the service, policy, and research needs as well as overall strategies to better protect children exposed to domestic violence. Results Respondents articulated four primary themes of (a) building general education and awareness of the effects of domestic violence exposure on children; (b) the need for trauma-informed care; (c) the salience of cultural humility in serving affected families; and (d) essential collaboration across service domains. Respondents discussed these themes in the context of four key systems of care: the clinical or therapy, family, school, and judicial systems. Conclusions Future research should integrate the voices of affected children and families as well as examine models for effectively implementing these recommendations into practice settings.
Random projection-based auxiliary information can improve tree-based nearest neighbor search

Abstract Nearest neighbor search using random projection trees has recently been shown to achieve superior performance, in terms of better accuracy while retrieving less number of data points, compared to locality sensitive hashing based methods. However, to achieve acceptable nearest neighbor search accuracy for large scale applications, where number of data points and/or number of features can be very large, it requires users to maintain, store and search through large number of such independent random projection trees, which may be undesirable for many practical applications. To address this issue, in this paper we present different search strategies to improve nearest neighbor search performance of a single random projection tree. Our approach exploits properties of single and multiple random projections, which allows us to store meaningful auxiliary information at internal nodes of a random projection tree as well as to design priority functions to guide the search process that results in improved nearest neighbor search performance. Empirical results on multiple real world datasets show that our proposed method significantly improves nearest neighbor search accuracy of a single tree compared to baseline methods.
Natural Products for the Treatment of Pain: Chemistry and Pharmacology of Salvinorin A, Mitragynine, and Collybolide.

Pain remains a very pervasive problem throughout medicine. Classical pain management is achieved through the use of opiates belonging to the mu opioid receptor (MOR) class, which have significant side effects that hinder their utility. Pharmacologists have been trying to develop opioids devoid of side effects since the isolation of morphine from papaver somniferum, more commonly known as opium by Serturner in 1804. The natural products salvinorin A, mitragynine, and collybolide represent three nonmorphinan natural product-based targets, which are potent selective agonists of opioid receptors, and emerging next-generation analgesics. In this work, we review the phytochemistry and medicinal chemistry efforts on these templates and their effects on affinity, selectivity, analgesic actions, and a myriad of other opioid-receptor-related behavioral effects.
Association of Cancer History and Health Care Utilization Among Female Immigrants Using NHANES 2007-2016 Data.

Despite health disparities in preventive care among adult female immigrants, the extent to which their health service utilization is influenced by a cancer history remains largely unknown. Using Andersen’s behavioral model, 2007–2016 National Health and Nutrition Examination Survey data were analyzed to examine the influence of a cancer history on health service utilization among adult immigrant women. Multivariate logistic regression models assessed factors related to past year health care utilization, operationalized as an outpatient doctor’s visit and an inpatient overnight hospital stay. Once other factors were considered, a past cancer history increased the likelihood of a past year inpatient overnight hospital stay, but was not associated with a past year outpatient doctor’s visit. An outpatient doctor’s visit for adult female immigrant cancer survivors would provide an opportunity for essential preventive health services. They must be educated about the importance of ongoing outpatient care for cancer surveillance and health maintenance.
Abstract 16617: Multimodality Imaging Approach in Delivery and Tracking of a Novel Imageable Hydrogel in a Chronic Porcine Infarct Model

Introduction: Left ventricular (LV) remodeling is a known complication from myocardial infarction (MI). Intramyocardial hydrogel (HG) delivery can potentially prevent LV remodeling post MI. We eval...
Reassemblig Social Security: A Survey of Pension and Health Care Reforms in Latin America

A description in a comparative manner of the social security pensions and health care reforms implemented in the 20 countries of Latin America. Evaluation of the reforms results and impact on conventional social security principles, as well as testing on whether the reforms presumed effects have materialized. Based on 44 statistical tables and more than 500 bibliographical sources.
The genetic architecture of larval aggregation behavior in Drosophila.

Many insect species exhibit basal social behaviors such as aggregation, which play important roles in their feeding and mating ecologies. However, the evolutionary, genetic, and physiological mecha...
Mathematical modeling for charging/discharging processes of batteries/nanobatteries

Abstract Mathematical modeling of batteries has several advantages including (i) helping engineers to design the battery and the micro −/nanostructure of the battery electrodes to achieve the desired performance for a targeted applications, (ii) helping researchers to decrease the number of experiments, (iii) decreasing the time and cost of the battery development, and (iv) fundamental understanding the phenomena occurring in the battery. There are many types of batteries and nanobatteries as reported by different researchers. Although the development of a general mathematical model that can cover all types of batteries may not be practical, there are some physical and chemical phenomena that may be common in all batteries. In this chapter a physics-based, continuum-scale modeling of batteries, with focus on rechargeable lithium-ion batteries, is presented.
Parallel Compressors

A subclass of generalized parallel counters, called parallel compressors, is introduced in this correspondence. Under present-day packaging technology, parallel compressors with their higher compression ratio and fewer input/output pins are more efficient in multiple operand addition and multiplication than parallel counters. Cost and time bounds are obtained for schemes using parallel compressors for reduction of N summands to m summands. Furthermore, a method for synthesizing large parallel counters using only one type of parallel compressor is given.
Dynamic pavement response analysis under wide-base tyre considering vehicle-tyre–pavement interaction

The new generation of wide-base tyres shows sustainable benefits in trucking operations and environmental impacts due to less rolling resistance at tyre–pavement interface. It is critical to estima...
Structure-Dependent Stability of Lipid-Based Polymer Amphiphiles Inserted on Erythrocytes

Cell-based therapies have the potential to transform the treatment of many diseases. One of the key challenges relating to cell therapies is to modify the cell surface with molecules to modulate cell functions such as targeting, adhesion, migration, and cell–cell interactions, or to deliver drug cargos. Noncovalent insertion of lipid-based amphiphilic molecules on the cell surface is a rapid and nontoxic approach for modifying cells with a variety of bioactive molecules without affecting the cellular functions and viability. A wide variety of lipid amphiphiles, including proteins/peptides, carbohydrates, oligonucleotides, drugs, and synthetic polymers have been designed to spontaneously anchor on the plasma membranes. These molecules typically contain a functional component, a spacer, and a long chain diacyl lipid. Though these molecular constructs appeared to be stably tethered on cell surfaces both in vitro and in vivo under static situations, their stability under mechanical stress (e.g., in the blood flow) remains unclear. Using diacyl lipid-polyethylene glycol (lipo-PEG) conjugates as model amphiphiles, here we report the effect of molecular structures on the amphiphile stability on cell surface under mechanical stress. We analyzed the retention kinetics of lipo-PEGs on erythrocytes in vitro and in vivo and found that under mechanical stress, both the molecular structures of lipid and the PEG spacer have a profound effect on the membrane retention of membrane-anchored amphiphiles. Our findings highlight the importance of molecular design on the dynamic stability of membrane-anchored amphiphiles.
Osmoregulatory alterations in taurine uptake by cultured human and bovine lens epithelial cells.

PURPOSE. Comparative assessment of cultured human lens epithelial cells (HLECs) and bovine lens epithelial cells (BLECs) established the nature of the relationship between taurine-concentrating capability and intracellular polyol accumulation or extracellular hypertonicity. METHODS. The kinetic characteristics of active taurine accumulation based on the measurement of in vitro [ 3 H]-taurine uptake were resolved by side-to-side review of cultured HLECs and BLECs pre-exposed to either galactose-supplemented medium or extracellular hypertonicity. Competitive RT-PCR was used to appraise variation in taurine transporter (TauT) mRNA abundance from cells maintained in hyperosmotic medium over a 72-hour exposure period. RESULTS. The capacity to accumulate [ 3 H]-taurine was significantly lowered after prolonged (20-hour) incubation of cultured BLECs in 40 mM galactose in contrast to HLECs, the latter cells' velocity curve being indistinguishable from control cells in physiological medium. Inhibition of the intracellular taurine transport site appeared to he noncompetitive, in that there was a marked reduction in the V max without significant alteration in the K m to a high-affinity transport site. Galactitol content in BLECs exceeded five times that found in HLECs. The coadministration of the aldose reductase inhibitor, sorbinil, with 40 mM galactose completely prevented the inhibitory effect of galactose on [ 3 H]-taurine uptake. Acute exposure (3 hours) of HLECs and BLECs to a range of 10 to 40 mM galactitol or 10 to 40 mM galactose plus sorbinil-supplemented medium suggested by Dixon plot that neither galactitol nor galactose interacted with the extracellular taurine transport site. In contrast, [ 3 H]-taurine accumulation was markedly elevated in both HLECs and BLECs after prolonged exposure to galactose-free medium made hyperosmotic by supplementation with sodium chloride. The enhanced taurine uptake capacity involved increase in peak velocity (V max ) without significant change in Michaelis-Menten constant (K m ). Cultured HLECs and BLECs responded to hypertonicity with an inducible but transitory upregulation of TauT mRNA. CONCLUSIONS. These results demonstrate that lens epithelial cells express a high-affinity TauT protein capable of active uptake, but predisposed to inhibition by intracellular galactitol when the sugar alcohol is present in sufficiently high concentration to interfere with cell metabolism. Furthermore, lens epithelial cells respond to hypertonic stress by raising taurine transport activity. The increase in taurine uptake is due to an increase in the number of high-affinity TauTs expressed as a result of an increase in the manifestation of taurine mRNA stemming from exposure to hypertonic medium.
Prior Target Valuation Changes and Acquirer Announcement Returns in Acquisitions of Recently Listed Targets

We provide new insights into the determinants of acquirer announcement returns with a unique sample of targets that are acquired within three years of their IPOs. Existing studies of acquisitions of private and established public targets find positive relations between acquirer announcement returns and prior target valuation changes. In our sample of recently listed targets, we measure the prior target valuation change as the return from the IPO offer price to two weeks before the acquisition. Inconsistent with the behavioral biases based on prospect theory studied in the related literature, the relation between acquirer announcement returns and targets’ returns since their IPOs is negative. We separate our target prior return variable into two components, the target’s first day return (IPO underpricing) and the return from the first day close until two weeks before the acquisition (Prior return). We contend that IPO underpricing is a proxy for target valuation uncertainty and Prior return is a proxy for target distress-related bargaining power. The positive relations of these two variables to other proxies for target valuation uncertainty and target distress support our interpretation. Both IPO underpricing and Prior return have significantly negative relations with acquirer announcement returns. Therefore, our empirical findings show that rational causes related to target valuation uncertainty and bargaining power explain a large part of the effect that prior target valuation changes have on acquirer announcement returns. Our study also adds to the debate over how much irrational behavior, as opposed to rational actions, affect major corporate events.
Fuel chemistry impact on vented fuel pin design

Venting and pressure equalization of gas-cooled fast breeder reactor (GCFR) fuel rods can be maintained only as long as axial gas transport paths are available and operating within the fuel pin. Analysis of the chemistry expected within an irradiated GCFR fuel pin shows that axial gas transport paths may become plugged due to the migration of fission product cesium and the formation of low density cesium-urania or cesium-fuel compounds. Cesium transport in the fuel and blanket is controlled by oxygen concentrations and by temperature distribution. Analysis of the shorter Experimental Breeder Reactor II in-reactor fuel pins suggests cesium will be retained in the much longer fast test reactor pins. This will lead to minimal plugging of the gas transport paths.
Predictability of Weather and Climate: Ensemble-based atmospheric data assimilation

Ensemble-based data assimilation techniques are being explored as possible alternatives to current operational analysis techniques such as 3or 4-dimensional variational assimilation. Ensemblebased assimilation techniques utilize an ensemble of parallel data assimilation and forecast cycles. The background-error covariances are estimated using the forecast ensemble and are used to produce an ensemble of analyses. The background-error covariances are flow dependent and often have very complicated structure, providing a very different adjustment to the observations than are seen from methods such as 3dimensional variational assimilation. Though computationally expensive, ensemble-based techniques are relatively easy to code, since no adjoint nor tangent-linear models are required, and previous tests in simple models suggest that dramatic improvements over existing operational methods may be possible. A review of the ensemble-based assimilation is provided here, starting from the basic concepts of Bayesian assimilation. Without some simplification, full Bayesian assimilation is computationally impossible for model states of large dimension. Assuming normality of error statistics and linearity of error growth, the state and its error covariance may be predicted optimally using Kalman filter (KF) techniques. The ensemble Kalman filter (EnKF) is then described. The EnKF is an approximation to the KF in that background-error covariances are estimated from a finite ensemble of forecasts. However, no assumptions about linearity of error growth are made. Recent algorithmic variants on the standard EnKF are also described, as well as methods for simplifying the computations and increasing the accuracy. Examples of ensemble-based assimilations are provided in simple and more realistic dynamical systems.
Capacity payments and the pricing of reliability in competitive generation markets

In restructured electric power industries around the world, power pool designers have enabled generators to earn revenues consisting of energy and capacity payments. This paper discusses uses and abuses of capacity payments, and links provision of these payments to the issue of pricing reliability. A general formula for determining the ideal capacity price in a generation supply system is presented and the theoretical basis discussed. Methods of achieving an ideal level of system reliability through price-setting of capacity payments (in more regulated markets) and through price discovery (in more competitive markets) are contrasted. The paper concludes with market design recommendations that could better realize customer preference for reliability at prices customers are willing to pay.
On the minimum-phase approximation of head-related transfer functions

The head-related transfer function embodies the amplitude and phase transformations accompanying a sound source from a fixed position in space to the eardrum. These transformations, which primarily result from the interaction of the acoustic wave with the complex geometry of the head and pinna, are known to be the principal determinants of source location. It is especially known that the interaural time differences (ITDs) are encoded by the phase spectra of the HRTFs at the two ears. In this study we explore a model of the HRTF which approximates the HRTF as a minimum phase function. The model is tested both theoretically and through psychophysical experiments. Results suggest that a minimum phase representation of the phase spectra, augmented by a position-dependent, frequency-independent ITD, is an adequate description of the HRTF phase. Both the scientific and the practical consequences of this result shall be discussed.
Clinical implications of new findings in HIV basic research

HIV has been studied extensively over the past 25 years. Insights into the different stages of the virus’ replication cycle and its interaction with host-cell proteins have led to the development of an armamentarium of effective antiretroviral medications. These antiviral drugs have dramatically changed the prognosis for HIV-infected subjects from an inevitable march towards death to a chronic disease with a potentially normal lifespan. Even with these successes, there is a continuing need to provide new drugs, especially those effective against drug-resistant viruses, to devise optimal strategies to prevent adverse events from either immunosuppression or the antiretroviral medications, and to develop treatments aimed at eliminating virus replication in the absence of antiviral drugs. In this review, how these important issues are being addressed will be highlighted, emphasizing clinical implications from some recent basic science studies and demonstrating how they could change the face of HIV therapeutics over the next 5–10 years.
The field-scale evaluation of herbicide-tolerant genetically modified crops conducted in the UK (1998–2003)

In 1998 the UK Government, in conjunction with Supply Chain Initiative on Modified Agricultural Crops (SCIMAC, a cross-industry group representing the supply chain), established a large-scale programme to examine the impact of genetically modified herbicide-tolerant crops on farmland biodiversity. The trials programme lasted three years and was conducted by a consortium of scientists who were responsible to an independent scientific subcommittee. The background to the establishment of these trials is described and the political pressures facing the Government at that time and the reactions of key stakeholders are discussed. The field-scale evaluations were a pioneering project to examine the impact of genetically modified crops on farmland biodiversity. The exercise was one of the largest experiments ever carried out to measure the environmental impact of specific farming practices, and shows that robust results can be obtained, while the resultant database represents a wealth of ecological information on three important arable crops â€“ beet, maize and oilseed rape. It is clear that other such trials could be carried out to test other variables as part of a longer-term effort to steer farm management systems in ways more acceptable to society. However, in view of their costs (both to the UK Government and the technology providers) together with the adverse response by the environmental campaign groups, and the length of time needed to carry out the work, it seems unlikely that an exercise of similar scale will be undertaken in the near future.
Cytotoxicity of North Dakota Plants I.: In Vitro Studies

In this study, a method is presented for the direct determination of cytotoxicity and antitumor activity of plant materials in vitro using HeLa cells. Fifty poisonous plants representing 96 plant parts were tested by this method, out of which 25 plants showed limited cytotoxicity and six plants were found to be highly cytotoxic. This procedure can be used on a large scale prior to in vivo evaluation.
Comparing resident measurements to attending surgeon self-perceptions of surgical educators.

Abstract Objective The purpose of this study was to evaluate the initiation and utility of evaluating attending surgeons as educators by resident trainees. Additionally, we were interested in comparing resident measurements to attending self-perceptions. Methods A written evaluation form, (utilizing five-point ordinal scale assignments) queried respondents regarding the performance of surgical attendings in the operating room, and other clinical settings. A similar form was distributed to the faculty members, which they used to evaluate themselves. Mean scores were determined, as were comparisons between self-perception and resident assessments. Differences in scores with p values less than 0.05 were considered statistically significant. Results Thirty-six residents evaluated 23 attendings. Mean assignments by residents of performance in the operating room, other clinical settings, and overall scores for all faculty members as a group were 4.22 ± 0.04, 4.11 ± 0.03, and 4.16 ± 0.03, respectively, with a score of five, generally corresponding to a most favorable rating. When overall scores were analyzed, 10 attendings received scores that differed significantly from those received by their peers, with half of subjects above, and the other half being below the 95% confidence interval. Eighteen (78%) of attendings completed the self-evaluation forms, and of these, 11 (61%) had self-perceptions that differed significantly from overall scores as reported by the residents. Conclusions Our evaluation process delineated significant differences among attending faculty members and identified individual strengths and weaknesses. Many educators’ self-perceptions differed significantly from resident assessments, and attendings who did not evaluate themselves scored lower than their peers.
Identifying channel-specific impairments in cochlear implant patients via partial least squares discriminant analysis of speech-token confusion matrices

It is not uncommon for cochlear implant patients to have individual electrodes that produce anomalous percepts that impair or prevent the effective transmission of auditory information. Exhaustive psychophysical testing to detect all such information channels is time prohibitive; however, if impaired channels could be identified quickly then the application of remediation strategies becomes more cost-effective. Previous studies have suggested that the missing speech information could produce a predictable pattern of errors in speech-token identification tasks [1, 2]. This study investigates the application of partial least squares discriminant analysis to identifying the presence of channel-specific impairments based on confusion matrices generated from vowel and consonant token identification tasks. The results of this study, using normal-hearing subjects tested with acoustic models, suggest that the partial least squares discriminant analysis can successfully distinguish impaired and unimpaired models, as well as identify channel-specific impairments, without requiring a significant amount of labeled training data.
Cognitive functioning moderates the relation between Attention Deficit Hyperactivity Disorder symptoms and alcohol use in women.

Previous work revealed that cognitive functioning moderated the relation between Attention Deficit Hyperactivity Disorder (ADHD) Symptoms and alcohol use [Alcohol., Clin. Exp. Res. 23 (1999) 224]. ADHD Symptoms correlated significantly with alcohol use for individuals with a poorer performance on tasks assessing prefrontal area functioning but not for individuals with higher scores on these tasks. The current study proposes to replicate this previous work and extend it in three ways. These include using a sample consisting solely of women, including the current DSM-IV [American Psychiatric Association (1994). Diagnostic and statistical manual of mental disorders (4th ed., revised). Washington, DC: Author] criteria for ADHD, and increasing the number of measures to assess cognitive functioning and drinking habits. Eighty-two female undergraduates completed four measures of alcohol use, three measures of ADHD, and six measures of cognitive functioning. Stacked two-group analyses replicated the previous moderator effect. Alcohol use and ADHD symptoms correlated .31 (ns) for the individuals who scored higher on the neuropsychological tasks. However, these constructs correlated .53 (P<.05) for individuals with lower scores on these tasks. Better performance on tasks assessing prefrontal area functioning may protect individuals from drinking in accordance with their ADHD symptoms.
PERIOD CHANGES OF CLOSE BINARY SYSTEMS

A brief review of the physical mechanisms that could produce the observed orbital period changes in close binaries, the methods used to study them, and a general discussion is given.
Diffraction-free beams generated with programmable spatial light modulators

Diffraction-free beams are generated by the use of diffractive optical elements written on a spatial light modulator (SLM). By alteration of the pattern placed on the SLM, the axis of propagation can be both shifted laterally and rotated. We present experimental results obtained by use of a magneto-optic SLM.
Arbitrary Structures Fabricated by Focused Ion Beam Milling

Optical components at the nanoscale are crucial for developing photonics and integrated optics. Device with ultrasmall dimensions is of particular importance for nanoscience and electronic technology. Among all the manufacturing tools, the focused ion beam is a critical candidate for machining and processing optical devices at the nanoscale. Here, we experimentally demonstrate the fabrication of nanodevices with arbitrary shapes and different potential applications using focused ion beam techniques.
Toward a theory of public sector entrepreneurship

Existing theories of public sector entrepreneurship lack a sense of entrepreneurial discovery ubiquitous in human action. Instead, existing theories emphasise rational calculation in a public sector setting. Existing theories of public sector entrepreneurship, therefore, are inadequate to account for the observed entrepreneurial behaviour in political and bureaucratic settings. The purpose of this paper is to redress the limited theories of public sector entrepreneurship by integrating Kirznerian and Schumpeterian theories of entrepreneurship with Buchanan and Tullock's constitutional political economy to move toward a theory of public sector entrepreneurship. The following analytic definition is offered: Public sector entrepreneurship occurs whenever a political or governmental actor is alert to, and acts on, potential political profit opportunities, thus equilibrating the policy subsystem in which the actor is embedded and moving it toward a new equilibrium.