cssi/SciSciGPT-SciSciNet huggingface dataset:
A High-Frequency Multipeak Model for Wide-Angle SAR Imagery

A new modeling method for representing distributed scattering centers in wide-angle synthetic aperture radar (SAR) is presented. The proposed multipeak model approximates amplitudes of localized image peaks that typically appear at a single pixel or as an in-line set of pixels in a SAR image. In this way, the multipeak model is an improvement over existing peak models which poorly represent distributed canonical scatterers, such as the common dihedral with a fold line oriented parallel to the imaging plane. The model is derived from a wide-angle approximation of the well-known attributed scattering center or parametric models when under the action of a linear imaging operator. It is shown that, under typical imaging conditions of 10 ° or more in the synthetic aperture, the multipeak model approximates the image peak amplitudes due to distributed canonical scatterers as if they are due to an equivalent point scatterer with an azimuth-independent dispersive amplitude function in the spectral domain. This improves parameter estimation and scatterer classification, and it is also shown that the imaging relative error due to the approximation is less than 2% for other common image processing conditions such as tapered windowing in azimuth and when the canonical scatterer is at least ten wavelengths in size. A distinct advantage of the multipeak model over point scatterer models is that parameter estimation and scatterer classification can be performed solely in the spatial domain on a pixel-by-pixel basis and efficiently integrated within a linear SAR imaging process. To illustrate the benefits and limitations of the approach, parameter estimation and scatterer classification experiments are presented using simulated SAR data.
Family history of alcohol dependence and initial antidepressant response to an N-methyl-D-aspartate antagonist.

Background A high rate of comorbidity exists between mood disorders and alcohol dependence. Furthermore, both ketamine, a dissociative anesthetic with a recently described rapid-onset antidepressant effect, and ethanol are N -methyl-D-aspartate (NMDA) receptor antagonists. Previous investigations of healthy individuals with a family history of alcohol dependence have found that these individuals have an attenuated response to ketamine's perceptual disturbance and dysphoric effects similar to that found in individuals with a self-reported history of alcohol dependence. This study investigated whether a family history of alcohol dependence influences ketamine's initial antidepressant effect. Methods Twenty-six subjects with DSM-IV treatment-resistant major depression were given an open-label intravenous infusion of ketamine hydrochloride (.5 mg/kg) and rated using various depression scales at baseline, 40, 80, 120, and 230 min postinfusion. The primary outcome measure was Montgomery-Asberg Depression Rating Scale (MADRS) scores. Results Subjects with a family history of alcohol dependence showed significantly greater improvement in MADRS scores compared with subjects who had no family history of alcohol dependence. Conclusions A family history of alcohol dependence appears to predict a rapid initial antidepressant response to an NMDA receptor antagonist.
A Computerized Provider Order Entry Intervention for Medication Safety During Acute Kidney Injury: A Quality Improvement Report

Background Frequently, prescribers fail to account for changing kidney function when prescribing medications. We evaluated the use of a computerized provider order entry intervention to improve medication management during acute kidney injury. Study Design Quality improvement report with time series analyses. Setting & Participants 1,598 adult inpatients with a minimum 0.5-mg/dL increase in serum creatinine level over 48 hours after an order for at least one of 122 nephrotoxic or renally cleared medications. Quality Improvement Plan Passive noninteractive warnings about increasing serum creatinine level appeared within the computerized provider order entry interface and on printed rounding reports. For contraindicated or high-toxicity medications that should be avoided or adjusted, an interruptive alert within the system asked providers to modify or discontinue the targeted orders, mark the current dosing as correct and to remain unchanged, or defer the alert to reappear in the next session. Outcomes & Measurements Intervention effect on drug modification or discontinuation, time to modification or discontinuation, and provider interactions with alerts. Results The modification or discontinuation rate per 100 events for medications included in the interruptive alert within 24 hours of increasing creatinine level improved from 35.2 preintervention to 52.6 postintervention ( P P Limitations Single tertiary-care academic medical center; provider actions were not independently adjudicated for appropriateness. Conclusions A computerized provider order entry–based alerting system to support medication management after acute kidney injury significantly increased the rate and timeliness of modification or discontinuation of targeted medications.
An informational pathway to the development of a contamination-related memory bias

Abstract Background and objectives Following from previous research in which post-encoding suggestions of threat led to the development of a memory bias (in the presumed absence of an attentional bias; Senn & Radomsky, 2012), we sought to examine whether the development of a similar threat-relevant memory bias could be fostered via a purely informational pathway. Methods A vignette about a classroom interaction was read aloud to (n = 96) undergraduate participants who then completed a post-encoding recall test. Participants were told that the experimenter forgot to read the last sentence of the vignette, and were then randomly assigned either to the Threat condition, in which the additional statement indicated that a character in the vignette had a highly contagious flu, or to the No-Threat condition, in which the additional statement indicated that a character in the vignette had been accepted to graduate school. A second recall test was then administered. Results Participants in the Threat condition (but not those in the No-Threat condition) demonstrated aproportionate memory bias in favor of threatening information. This bias was not evident at the initial recall test. Limitations Time spent engaging in active recall was not assessed. Also, although the study was designed to minimize demand characteristics, it is possible that these played a role. Conclusions An explicit memory bias for threat can be created through informational means alone, even when no threat was present at encoding. Results are discussed in terms of pathways to fear and of cognitive approaches to understanding and treating anxiety disorders.
Side-chain contributions to membrane protein structure and stability

The molecular forces that stabilize membrane protein structure are poorly understood. To investigate these forces we introduced alanine substitutions at 24 positions in the B helix of bacteriorhodopsin and examined their effects on structure and stability. Although most of the results can be rationalized in terms of the folded structure, there are a number of surprises. (1) We find a remarkably high frequency of stabilizing mutations (17%), indicating that membrane proteins are not highly optimized for stability. (2) Helix B is kinked, with the kink centered around Pro50. The P50A mutation has no effect on stability, however, and a crystal structure reveals that the helix remains bent, indicating that tertiary contacts dominate in the distortion of this helix. (3) We find that the protein is stabilized by about 1kcal/mol for every 38A(2) of surface area buried, which is quite similar to soluble proteins in spite of their dramatically different environments. (4) We find little energetic difference, on average, in the burial of apolar surface or polar surface area, implying that van der Waals packing is the dominant force that drives membrane protein folding.
Strategies of Nucleus Formation in Agglomerative Clustering Techniques

Strategies de formation des noyaux dans les techniques de classification. Les techniques de classification sont largement reconnues dans les sciences sociales et biologiques. De nombreuses techniques basees sur des algorithmes varies ont ete diffusees. Malheureusement, peu d'attention a ete portee a la maniere dont les noyaux sont formes. C'est un enjeu important: le choix des noyaux initiaux peut grandement affecter la constitution des classes finales. Dans cet article sont presentees les effets de quatre techniques de formation des noyaux: une methode objective et une methode subjective de minimalisation de la variance inter-cluster; une methode objective et une methode subjective de maximalisation de la variance inter-cluster. Je conclue que la pratique habituelle d'initialisation du cluster avec une paire reciproque pour minimiser la variance intra a la fois pour les methodes de liens uniques et de liens complets. Pour les techniques centrees sur la variance inter-cluster c'est une methode subjective ...
Assessing familial aggregation with an ordinal response

A latent variable model is considered for the analysis of twin data with an ordinal response. The underlying latent multivariate normally distributed variable is expressed in terms of genetic and environmental effects, and the variance components associated with these effects are estimated. We illustrate this approach with analysis of the NHLBI Twin Study. Model assessment is ascertained by proposing a goodness-of-fit test for ordered categorical data. Extensions of this approach for the investigation of how genetic effects vary over time are discussed.
GIS AND URBAN STUDIES: POSITIVISM, POST-POSITIVISM, AND BEYOND

(1994). GIS AND URBAN STUDIES: POSITIVISM, POST-POSITIVISM, AND BEYOND. Urban Geography: Vol. 15, No. 3, pp. 258-278.
Flt3 ligand generates morphologically distinct semimature dendritic cells in ovalbumin-sensitized mice

Dendritic cells (DCs) are unique antigen presenting cells that are immature prior to their encounter with an antigen. Exposure to allergens induces the maturation of DCs with changes in morphology and presence of dendrites. Here, we demonstrate that the DCs in the lungs of ovalbumin (OVA)-sensitized and challenged mice are more mature owing to their pronounced dendrites than the DCs in the lungs and spleen of PBS-treated mice, which are immature and possess cytoplasmic veils. Intermediate to these two groups are the DCs in the Flt3 ligand-treated group that exhibit comparatively fewer dendrites and cytoplasmic veils and hence are classified as semimature. Presence of large numbers of well-developed mitochondria and rough endoplasmic reticulum in myeloid DCs from both lungs and spleen of OVA-sensitized and challenged mice indicate greater functional activity. Additionally, DCs from the OVA-sensitized and challenged mice also exhibit fat and glycogen stores, which are indicative of a mature population. In addition, treatment of the animals with Flt3 ligand attenuated airway hyperresponsiveness to methacholine in OVA-sensitized and challenged mice. These data suggest that morphological features could be indicative of the maturation and distinct functional state of DCs, and this could be associated with underlying mechanisms of Flt3 ligand-induced immunomodulation in allergic asthma.
When a man thinks he has female traits--constructing femininity and masculinity: methodological potentials and limitations.

In everyday life, people are confronted with common beliefs about how women and men differ from each other. These beliefs make them wonder about their personal femininity and masculinity. But what hides behind these constructs? In this article, we will discuss the potential and limitations of different definitions. We will focus on methodological issues which can trigger new discussions about the social implications of gender differences—which are not part of this paper. One of the major questions here is whether it is methodologically justifiable (legitimate) to make individual predictions based on group differences. An issue that is not only relevant in regards to femininity and masculinity. In general, all definitions of masculinity and femininity show more limitations than potentials. They are either neglecting certain sub-groups or are based on stereotypes (either displaying common beliefs or exaggerated group differences). Individual predictions derived from these constructs are questionable due to oversimplification/reductionism (e.g., when forming groups). By pointing out that constructs like femininity and masculinity can in fact limit an individual’s development, it is suggested to clearly differentiate between different types of differences and to clearly state what can and cannot be said when “measuring” an individual’s masculinity and femininity. Since femininity and masculinity can be seen as example constructs, and generalizations are part of many research processes, general implications beyond these concepts are being discussed.
The effects of SiO2 barrier between active layer and substrate on the performance and reliability of polycrystalline silicon thin film transistors

We report on the performance and hot carrier stress (HCS) reliability of n-channel and p-channel poly-Si thin film transisters (TFT)s fabricated on SiO2-coated 1737 glass or bare 1737 glass substrates. Low-pressure chemical vapor deposited (LPCVD) or atmospheric pressure chemical vapor deposited (APCVD) SiO2 with different thicknesses are used as the impurity diffusion barrier layers. We have found that the performance and HCS reliability of n-TFTs on SiO2-coated 1737 glass are superior to those of n-TFTs on bare 1737 glass. P-TFTs on SiO2-coated 1737 glass, on the other hand, are observed to perform better than p-TFTs on bare 1737 glass substrates, however p-TFTs on SiO2-coated 1737 glass are seen to undergo larger improvements in their OFF current, IOFF, following the HCS compared to p-TFTs on bare 1737 glass. We also explore the impact of SiO2 coating thickness on the performance and HCS reliability of the TFTs. The HCS reliability of the TFTs on SiO2-coated 1737 glass substrates is observed to depend on the SiO2 coating thickness. This was explained in terms of a phenomenological model which involves impurity and grain boundary traps. The presence of the former type of traps is controlled by the presence or absence of the SiO2 coating, whereas the grain boundary traps are proposed to be sensitive to compressive and tensile stresses in the SiO2 coating layer which are, in turn, dependent on the layer's thickness.
Secondary craters from large impacts on Europa and Ganymede: Ejecta size–velocity distributions on icy worlds, and the scaling of ejected blocks

Abstract We have mapped fields of secondary craters around three large primary craters on Europa and Ganymede and estimated the size and velocity of the fragments that formed the secondaries using updated scaling equations for ice impacts. We characterize the upper envelope of the fragment size–velocity distribution to obtain a function for the largest fragments at a given ejection velocity. Power-law velocity exponents found in our study of icy satellite secondary fields are compared to the exponents found for similar studies of mercurian, lunar, and martian craters; for all but basin-scale impacts, fragment size decreases more slowly with increasing ejection velocity than on rocky bodies. Spallation theory provides estimates of the size of ejected spall plates at a given velocity, but this theory predicts fragments considerably smaller than are necessary to form most of our observed secondaries. In general, ejecta fragment sizes scale with primary crater diameter and decrease with increasing ejection velocity, υej, by 1/υej or greater, and point-source scaling implies a relation between the two. The largest crater represented in any of these studies, Gilgamesh on Ganymede, exhibits a relatively steep velocity dependence. Extrapolating the results to the escape speed for each icy moon yields the size of the largest fragment that could later re-impact to form a so-called sesquinary crater, either on the parent moon or a neighboring satellite. We find that craters above 2 km in diameter on Europa and Ganymede are unlikely to be sesquinaries.
Assessment of the learning curve for pancreaticoduodenectomy

Abstract Background Experience with the Whipple procedure has been associated with improved outcomes, but the learning curve for this complex procedure is not well defined. Methods Outcomes with 162 consecutive Whipple procedures during the 1st 11.5 years of practice was documented in a prospective database. A period of low (≤11/y) and high (≥23/y) case volume was compared using the Wilcoxon rank-sum test and Fisher exact test. Results With low case volume, blood loss was higher (800 vs 400 mL, P = .001), more patients were transfused (44% vs 18%, P = .027), there were more complications (58% vs 46%, P = .0337), and a longer length of stay (10 vs 7 days, P = .006). There was only 1 mortality (.7%). Conclusions Frequent repetition of the Whipple procedure is associated with an improvement in quantifiable quality benchmarks, and improvement continues with extensive experience. However, with proper training and the right environment, this procedure can be performed during the learning curve with acceptable outcomes.
Biology of Mint Root Borer (Lepidoptera: Crambidae) and Control Options on California Peppermint

Mint root borer, Fumibotys fumalis (Guenee), larvae cause damage to peppermint by feeding on rhizomes belowground. This species can cause significant economic damage and occurs throughout all peppermint-growing regions in Washington, Oregon, Idaho, and California. Until 2009, managing economic populations was limited to fall or spring tilling, and postharvest application of the organophosphate insecticide, Lorsban. The recent registration in California of the reduced risk insecticides chlorantraniliprole, indoxacarb, methoxyfenozide, and spinetoram on peppermint potentially improves management tactics by including preharvest applications. A degree-day model, available through the Oregon State University, Integrated Plant Protection Center (OSU IPPC), provides information that could be used for applying preharvest insecticides targeting vulnerable life stages. In 2010 and 2011, large delta sticky traps baited with mint root borer sex pheromone were placed in commercial peppermint fields in Shasta and Siskiyou counties and used to validate the OSU IPPC model under California conditions. Moth capture data indicated that the OSU IPPC model did not provide a reliable prediction of emergence, peak flight, and 90% flight. In 2010, observed peak flight varied 10-25 days earlier than predicted by the OSU IPPC model. Observed 90% flight occurred ∼2 weeks earlier than predicted in Shasta County and nearly 1 month earlier than predicted in Siskiyou County during 2010 and 2011, respectively.
Superelectrophiles and the Effects of Trifluoromethyl Substituents

Trifluoromethyl-substituted superelectrophiles were generated in superacid (CF3SO3H) and their chemistry was examined. The strong electron withdrawing properties of the trifluoromethyl group are found to enhance the electrophilic character at cationic sites in superelectrophiles. This leads to greater positive charge-delocalization in the superelectrophiles. These effects are manifested by the superelectrophiles showing unusual chemo-, regio-, and stereoselectivity in reactions.
Reconstructing the human body using biomaterials

The use of metals and other materials to repair the human body has been recorded for centuries, dating back several millenia. Advances in biomaterials have enabled doctors and scientists to replace diseased body parts with natural or synthetic materials such as metals, ceramics, or polymers. In addition, recent advances in tissue engineering may soon enable the development of organs and tissues to replace those damaged by disease or trauma.
Methane-fueled thin film micro-solid oxide fuel cells with nanoporous palladium anodes

Abstract Methane-fueled thin film micro-solid oxide fuel cells (μSOFCs) based on palladium (Pd) anodes are discussed in this article. The μSOFCs are composed of porous platinum (Pt) cathodes, 8 mol.% yttria-stabilized zirconia (YSZ) ultrathin electrolytes, and Pd anodes – specifically, a Pt/YSZ/Pd heterostructure synthesized by physical vapor deposition. The Pt/YSZ/Pd μSOFCs exhibit a power density of 385 mW cm−2 and an open circuit voltage of 0.77 V at 550 °C. A detailed study on synthesis, microstructure and functional properties of the nanoporous Pd films is presented. Possible anodic methane reactions, carbon deposition on Pd anodes, and carbon suppression approaches are discussed. The results are of potential relevance to advancing low temperature micro-fuel cell technology using hydrocarbon fuels.
Multiple determinants of hospital programs.

Resume Les hospitaux generaux, concus pour des courts sejours, sont maintenant transformes et au lieu de facilites prevues en principe pour soigner les maladies aigues et les personnes serieusement blessees, ils deviennent des centres pour des traitements complexes pour toutes les formes de maladies, sans tenir compte s'il y a un danger pour la vie. D'innombrables facteurs technologiques, sociologiques et economiques se combinent et reagissent reciproquement comme determinants de l'organisation du personnel medical et du programme hospitalier, desquels seulement quelques-uns ont ete choisis pour une mention speciale, dans la croyance qu'il vont continuer d'etre des facteurs affectifs influents. La transformation est absolument complete. Les hopitaux sont parmi les institutions qui changent le plus rapidement, d'autant mieux que la population devient de plus en plus consciente de sa sante et qu'en consequence demande davantage et aussi un meilleur traitement. Quoique le cabinet de consultations prive est encore le local pour la majorite des traitements medicaux, les medecins aussi bien que les malades utilisent davantage les services d'hospitalisation et de consultations. Le programme de l'hospital est devenu une necessite accessoire pour la pratique medicale privee. Le fait que tant des forces pressent pour des nouveaux programmes hospitaliers, explique leur recente expansion rapide. Ces memes forces et d'autres continuent d'agir et presagent peutetre une expansion egale ou plus grande des programmes hospitaliers dans l'avenir et le developpement de modeles plus efficaces de l'organisation du personnel medical, en lui permettant de fonctionner.
Line-of-sight measurement in large urban areas using voxelized lidar

Recent advances in LIDAR technologies have increased the resolution of airborne instruments to the sub-meter level, which opens up the possibility of creating detailed maps over a large area. The ability to map complex 3D structure is especially challenging in urban environments, where both natural and manmade obstructions make comprehensive mapping difficult. LIDAR remains unsurpassed in its capability to capture fine geometric details in this type of environment, making it the ideal choice for many purposes. One important application of urban remote sensing is the creation of line-of-sight maps, or viewsheds, which determine the visibility of areas from a given point within a scene. Using a voxelized approach to LIDAR processing allows us to retain detail in overlapping structures, and we show how this provides a better framework for handling line-of-sight calculations than existing approaches. Including additional information about the instrument position during the data collection allows us to identify any scene areas which are poorly sampled, and to determine any detrimental effect on line-of-sight maps. An experiment conducted during the summer of 2011 collected both visible imagery and LIDAR at multiple returns per square meter of the downtown region of Rochester, NY. We demonstrate our voxelized technique on this large real-world dataset, and derive where errors in line-of-sight mapping are likely to occur.
Rectification and internal photoemission in metal/CVD diamond and metal/CVD diamond/silicon structures

Schottky diodes were formed with free-standing polycrystalline thin film diamond base as well as with polycrystalline diamond films grown on crystalline silicon. Current-voltage and internal photoemission measurements were used to characterize the Schottky diodes and the diamond film. Internal photoemission measurements yielded a barrier height of 1.15 eV. A comparison of experimental data for metal contacts to free-standing diamond films and those on silicon substrates indicates that both rectification and internal photoemission originate at the metal/diamond interface.
Achieving community borrower compliance with an urban university library's circulation policies: One university's solution

Abstract The University of Nevada, Las Vegas Library has taken steps to provide the community with access to its collections while safeguarding its resources. It requires external borrowers to register a major credit card and agree to have the Library charge replacement costs and fees to their accounts.
Effect of γ-irradiation on utilization of glycine carbons in biosynthesis of RNA and amino acids in the boll weevil.

Abstract Irradiation of boll weevils, Anthonomus grandis, caused a significant decrease in the amounts of valine, isoleucine, and histidine and an increase in the amount of cystine in the free amino acids but had no quantitative effect on the protein-bound amino acids. Also, in 4 hr it did not affect the incorporation of glycine-1-14C or glycine-2-14C into RNA or the synthesis of the ribonucleic acids. All the carboxyl-labelled carbon of glycine was incorporated into the same positions of both serine and glycine in both the free amino acid and the protein fractions, but some randomization occurred with the α carbon in both irradiated and normal insects. The α carbon of glycine contributed little to the formation of CO2; the carboxyl carbon contributed materially.
EV-Loc: integrating electronic and visual signals for accurate localization

Nowadays, an increasing number of objects can be represented by their wireless electronic identifiers. For example, people can be recognized by their phone numbers or their phones' WiFi' MAC addresses and products can be identified by their RFID numbers. Localizing objects with electronic identifiers is increasingly important as our lives become increasingly "digitalized". However, traditional wireless localization techniques cannot meet the fast growing needs of accurate and cost efficient localization. Some of these techniques require expensive hardware to achieve high accuracy, which is impractical for massive deployment. Others, such as WiFi RSSI based localization, are inaccurate and not robust to environmental noise. In this paper, we propose a new localization technique called EV-Loc. In EV-Loc, we use visual signals to help improve the accuracy of wireless localization. Our technique fully leverages visual signals' high accuracy and electronic signals' pervasiveness. To effectively couple these two signals, we design an E-V match engine to find the correspondence between an object's electronic identifier and its visual appearance. We implement our technique on mobile devices and evaluate it in real-world scenarios. The localization error is less than 1 m. We also evaluate our approach using large scale simulations. The results show that our approach is accurate and robust.
Regions of 23 S Ribosomal RNA Proximal to Transfer RNA bound at the P and E Sites

Abstract tRNAPhetranscribed in a T7 RNA polymerase system has been modified in such a way that 4-thiouridines have randomly replaced unmodified uridines. These 4-thiouridines serve as sites for conjugation of the cleavage reagent 5-iodoacetamido-1, 10-phenanthroline (IOP). 1,10-Phenantholine, when complexed with Cu2+in a reducing environment, causes hydrolysis of nearby nucleic acids. We show here that tRNA-phenanthroline (tRNA-OP) conjugates, when boundin situto the P- and E-sites of 70 S ribosomes, cause cleavage, mainly in domains I, III and V of 23 S ribosomal RNA (rRNA). The cleavage sites in domain V predominantly occur very close to or in the peptidyl-transferase region. The regions of domain I and III that are cleaved are apparently folded in the 50 S ribosomal subunit so as to be proximal to the peptidyl-transferase center. Most of the cleavage events occur whether the tRNA-OP conjugate is bound to ribosomes alone, or yeast tRNA is also present in the P/P hybrid state. Cleavages that occur only in the absence of yeast tRNA are limited to the 1100 region of domain II, and the 2800 region of domain VI. Cleavages that occur only in the presence of yeast occur in the 2170 region of domain V. The regions of 23 S rRNA in which tRNA-OP induced cleavage occur complement those sites shown by chemical protection and cross-linking to be in a close proximity to the tRNA. However, the cleavage approach allows a more versatile and expanded view of the near neighborhood of rRNA surrounding the tRNA. These results provide considerable information which will allow a more detailed modeling of the tertiary structure of the 50 S ribosomal subunit.
The silent ones: A review of sampling issues and biases pertinent to the area of pediatric oncology procedural pain

Pain related to procedures for pediatric oncology patients is a salient topic. Although these procedures can cause much distress, this area has been neglected in research. Previous research has suffered from serious sampling problems, such as using small, nonrepresentative, biased samples. In addition, little is known about the influence of sociocultural factors on the phenomena of pain in children. This article presents the results of a review of the past 10 years of pertinent literature, argues that sociocultural influences on pain need to be studied, and offers suggestions for improving sampling designs.
Principal Pressure in the Middle of Accountability

When a new superintendent is hired, Tom Thompson, middle school principal, is squeezed between complying with the demands of the district and cultivating a positive culture in his school. He wrestles with the stress of facing tough leadership choices that take a toll on his physical and mental health. Tom realizes that a career-ending move might result from a miscalculation of available options. This case discusses the role of the principal in the district hierarchy, the impact on school staff resulting from punitive district personnel policies, the development of relationships with a new supervisor, and the ethics of test administration underlying administrative decision making.
Joint placement of phasor and conventional power flow measurements for fault observability of power systems

The authors consider the problem of joint optimal placement of phasor measurement units (PMUs) and conventional power flow measurements to ensure observability under faulted conditions in power systems. The formulation is initially posed as a non-linear integer programming problem and then transformed into an equivalent integer linear programming (ILP) problem through boolean implications. The resulting ILP problem is solved for the optimal solution on IEEE 14, 30, 57 and 118 bus systems and a large 2383 bus Polish system. The placement results obtained with the proposed formulation require fewer PMUs for fault observability compared with systems with fixed locations of conventional measurements. The results thus potentially provide a more economical solution to observability under faults compared with those obtained solely with PMU placement.
Adrenal effects of low-dose aminoglutethimide when used alone in postmenopausal women with advanced breast cancer

Aminoglutethimide (Ag) is a potent aromatase-enzyme inhibitor used in the treatment of patients with breast cancer. In the past, it has been administered in doses of 1,000 mg/d (usually with 40 mg hydrocortisone). At these dose levels, the drug also affects multiple cytochrome P-450 enzymes, including enzymes for adrenal steroid biosynthesis. Recently, lower-dose regimens (500 mg/d) of Ag have been found to be just as effective for breast cancer therapy, but less toxic than the higher conventional dose. There is limited information on the adrenal effects at the lower dosages, and it is not known whether these effects are clinically significant. We measured basal and synthetic corticotropin (Cortrosyn)-stimulated levels of adrenal steroids in postmenopausal breast cancer patients before and during treatment with low-dose Ag (500 mg/d) administered without a glucocorticoid preparation. Basal levels of progesterone, 17-OH progesterone, and 11-deoxycortisol were higher after 2 months' treatment (P < .01). After ACTH injection, peak levels of progesterone and 17-OH progesterone were higher (P < .01), but in contrast, peak levels of 18-OH corticosterone were lower during treatment (P < .02). Basal and peak levels of cortisol, aldosterone, and all other adrenal steroids were unchanged during treatment. We conclude that low-dose Ag treatment leads to partial inhibition of the 21-hydroxylase, 11-hydroxylase, and 18-hydroxylase adrenal enzymes. Since cortisol and aldosterone secretion remained normal with minimal shunting to or accumulation of adrenal androgen compounds, we believe that the mild inhibition was compensated for by further endogenous ACTH stimulation.
Vitamin D deficiency in children with haemophilia

Background: Recent studies have shown that children with severe haemophilia could have moderately reduced bone density compared with gender- and age-matched control subjects. Patients with more established changes resulting from haemophilic joint disease exhibited the lowest bone mineral density. The reason for this includes factors such as lack of weight-bearing physical activity, lower height and weight reached by these patients, muscle atrophy and hepatitis C seropositivity. A lower peak bone density reached during late adolescence and young adulthood predisposes to the development of osteoporosis in the later years. Objective: While Vitamin D and calcium supplementation has been recommended by many authors for haemophiliacs, there are no studies looking at Vitamin D levels in these patients. The aim of this study was to evaluate for the prevalence of Vitamin D deficiency and the need for supplementation in the haemophiliac patients in our centre. Methods: The 25-hydroxy Vitamin D3 (25-OH D3), calcium, phosphorus and PTH levels were measured in patients between the ages of 1–18 years during their regular visits to the haemophilia centre. A 25-OH D3 level of >30ng mL−1 is considered as adequate, levels of 21–29 ng mL−1 indicates a relative insufficiency and a level <20ng mL−1 is defined by most experts as being absolutely Vitamin D deficient. Results: Of the 33 patients, 21 of them were Vitamin D deficient (63.6%). Calcium, phosphorus and PTH levels did not correlate with Vitamin D levels. Conclusions: Vitamin D deficiency is highly prevalent in patients with haemophilia in our centre, and given their propensity to develop osteopenia, Vitamin D supplementation is essential in this group of patients. As the calcium, phosphorus and PTH level do not correlate with Vitamin D levels, evaluation of Vitamin D deficiency needs the measurement of serum 25-hydroxy D3 level. The reasons for a deficiency of Vitamin D in these patients, the amount of supplementation needed and the effect of supplementation of Vitamin D on attaining the peak bone mass density of these patients need to be explored further. Vitamin D status in patients with haemophilia (25-OH D3 level) >30 ng mL−1 (normal) 21–29 ng mL−1 (relative insufficiency) <20 ng mL−1 (severe insufficiency) <30 ng mL−1 (vitamin D deficiency) Haemophilia A&B (# of patients) 12 9 12 21/33 = 63.6%
The isolation and characterization of 2-carboxyethyl adducts following in vitro reaction of acrylic acid with calf thymus DNA and bioassay of acrylic acid in female Hsd:(ICR)Br mice.

Abstract Reaction of acrylic acid (AA) at pH 7.0 and 37°C for 40 days with 2′-deoxyadenosine (dAdo), 2′-deoxycytidine (dCyd), 2′-deoxyguanosine (dGuo) and thymidine (dThd) resulted in the formation of 2-carboxyethyl (CE) adducts via Michael addition. The alkylated 2′-deoxynucleoside adducts isolated (percent yield after 40 days) were 1-CE-dAdo (5%), N6-CE-dAdo (11%) (via Dimroth rearrangement of 1-CE-dAdo), 3-CE-dCyd (7.5%), 7-CE-Gua (4%), 7,9-bis-CE-Gua (0.9%) (formed by reaction of AA with depurinated 7-CE-Gua during the course of the reaction) and 3-CE-dThd (0.5%). The products isolated following in vitro reaction of AA with calf thymus DNA at pH 7.0 and 37°C for 40 days were (nmol/mg DNA) 1-CE-Ade (9.9), N6-CE-Ade (8.2), 7-CE-Gua (7.2) and 3-CE-Thy (1.9). Compound 3-CE-Cyt was not detected. Thus the adducts formed following in vitro reaction of AA with DNA are identical to those formed by in vitro reaction of the carcinogen β-propiolactone (BPL) with DNA as reported in an earlier paper. Structures were assigned on the basis of identical UV spectra, Rf values on paper chromatograms and Rt values on HPLC as marker compounds prepared from reactions of BPL with 2′-deoxynucleosides and 2′-deoxynucleotides-5′-monophosphoric acids. AA was assayed for carcinogenic activity by s.c. injection (20 μmol, once a week for 52 weeks) in female Hsd: (ICR)Br mice. Two mice with sarcomas at the site of application were observed out of 30 mice. Malignancies were not observed in solvent and no-treatment controls. The bioassay results reported in this paper and elsewhere in the same strain of mice suggest that AA is a weak carcinogen in female Hsd: (ICR)Br mice.
Keynote: DNA-based molecular devices

We overview recent work in the field of DNA-based autonomous biomolecular devices. We particularly emphasize molecular assemblies and molecular devices that are (i) self-assembled: that is they assemble into DNA nanostructures in one stage without explicit external control, (ii) programmable: the tasks the molecular devices execute can be modified without an entire redesign and (ii) autonomous: they operate without external mediation (e.g. thermal-cycling). We describe recent experimental progress in DNA-based autonomous biomolecular devices that achieve: 2D patterning, computation, amplified sensing, and molecular nano-scale transport. These have taken the technology from a state of intriguing possibilities into demonstrated capabilities of quickly increasing scale, and we describe a number of very promising applications in the biomedical industry.
Diffusional relaxation of stress concentration at second phase particles

Abstract In general, an increase in the yield strength of a metal is accompanied by a decrease in its ductility. Often, this is because hard second phase particles which are designed into the microstructure to increase the yield strength also become sites of stress-concentration and cavity formation. However, at elevated temperature diffusion can relax these stress-concentrations and enhance ductility. Starting from fundamentals, we have calculated the strain-rate and temperature field in which ductility would be enhanced by this mechanism. Such ‘hot forming’ diagrams can be useful in the processing of materials.
Is obesity a risk factor for chronic kidney disease in children

There is a rapid increase worldwide in the prevalence of obesity in adults and children. Obesity is not only a comorbidity for chronic kidney disease (CKD) but may also be a risk factor for CKD. Epidemiological correlations and pathophysiological changes have been observed associating obesity with CKD. Low birth weight may be associated with both obesity and low nephron mass, leading to CKD later in life. Elevated levels of adipokines, such as leptin and adiponectin, in obesity may be factors in CKD pathogenesis and progression. Furthermore, various other factors, such as hypertension, increased cardiovascular morbidity, insulin resistance, dyslipidemia, and lipotoxicity, may play significant roles in the pathogenesis of CKD in obesity. Reduction in obesity, which is a potentially modifiable risk factor, might help decrease the burden of CKD in the population. Apart from individualized options, community-based interventions have the potential to create a strong impact in this condition.
Examining Variations among Researchers' and Teachers' Conceptualizations of Creativity: A Review and Synthesis of Contemporary Research.

Abstract Research exploring beliefs about creativity has produced valuable findings regarding how individuals conceptualize creativity, yet, to date, there has been no systematic synthesis of this literature. As such, the purposes of this review were twofold: (a) to explore researchers’ and teachers’ conceptualizations of creativity; and, (b) to analyze and synthesize the results of the studies examining teachers’ beliefs about creativity. To address these purposes, we analyzed peer-reviewed, empirical research studies of teachers’ beliefs about creativity appearing in the published literature. Our analysis incorporated documentation of the studies’ surface characteristics (i.e., topic, sample, design, and instruments) and identification of definitional patterns regarding the two key terms of the review namely creativity and beliefs. Based on our analysis of the reviewed studies, we propose a conceptual framework for beliefs about creativity, and overview conceptual issues derived from themes emerging in the relevant literature. Implications for instruction and research are forwarded.
Quantifying phthalate metabolites in human meconium and semen using automated off-line solid-phase extraction coupled with on-line SPE and isotope-dilution high-performance liquid chromatography--tandem mass spectrometry.

We developed an analytical method using off-line solid-phase extraction (SPE) coupled with on-line SPE and isotope-dilution high-performance liquid chromatography-tandem mass spectrometry (HPLC−MS/MS) to determine the concentrations of phthalate metabolites in human meconium and in semen. First, we used off-line SPE to remove interfering proteins and other biomolecules from the samples. Then, we preconcentrated the phthalate metabolites in the extract using on-line SPE before measuring them by HPLC−MS/MS. For most of the analytes, the limits of detection ranged between 0.2 and 0.7 ng/g for meconium and between 0.3 and 0.7 ng/mL for semen. The recovery after off-line SPE varied for most analytes between 65 and 99% at concentrations ranging from 3.0 to 30.0 ng/mL in semen and between 67 and 103% at concentrations ranging from 2.0 to 10.0 ng/mL in meconium. Precision measured by the relative standard deviation ranged from 3.2 to 19.1% for intraday and from 3.9 to 18.6% for interday. We validated this novel a...
Ferromagnetic Hyperthermia and Iodine 125 Brachytherapy in the Treatment of Choroidal Melanoma in a Rabbit Model

• Hyperthermia has been combined with conventional radiation methods to achieve enhanced tumor destruction. We combined iodine 125 seeds with ferromagnetic thermoseeds in a single plaque to simultaneously deliver radiation and heat in a rabbit model of choroidal melanoma. Initially, six ferromagnetic thermoseeds were placed in parallel on a 14-mm episcleral plaque. The plaques were placed on normal rabbit eyes and on eyes containing transvitreally implanted choroidal melanoma. The heating response was assessed in both normal and tumor-containing eyes. Rigid copper-constantan and flexible Baily thermocouples were used to monitor temperature responses. The animals were subjected to an electromagnetic field of 100 kHz, with power of 1100 to 1500 W. The thermoseeds autoregulated at 48.2°C. Scleral temperatures stabilized at 45.8°C ± 0.4°C (SD), while temperatures at the base of the tumor stabilized at 43.6°C ± 0.1°C. Ferromagnetic thermoseeds were then combined with iodine 125 seeds. Similar temperature responses were recorded, and autoradiographic findings confirmed a uniform radiation distribution. Varying the amount or type of ferromagnetic material in the thermoseeds allows the delivery of heat at virtually any temperature. Ferromagnetic hyperthermia may provide a more simplified approach over currently available methods of heat delivery.
Benchmark Studies for the Generalized Streamwise Periodic Heat Transfer Problem

This is a comparison of calculations performed with a scheme for handling streamwise-periodic boundary conditions with known solutions to the common problem of fully developed heat transfer in a plane duct. Constant value, constant flux, mixed boundary conditions, and linear wall flux (conjugate heat transfer) are all considered. Agreement is, in every case, near exact showing that the methodology may be applied with confidence to complex engineering problems with a variety of thermal wall boundary conditions.
Motional smearing of electrically recovered couplings measured from multipulse transients

The measurement of residual dipolar and quadrupolar coupling constants in the liquid phase by using an electric field to destroy the isotropic nature of molecular tumbling is complicated by charge-induced turbulent motion. In many cases this motion is due to charge injection at electrode surfaces, an effect that leads to an apparent removal of electrically recovered anisotropic spectral splittings when measured from a spin-echo () envelope modulation produced by a train of radio frequency rf pulses. To understand this averaging, the effect of quadrupolar couplings and enhanced molecular diffusion on free-in- duction, spin-echo, and Carr Purcell signals is analytically determined in the special case of homogeneous rf pulses. Additional signal damping due to rf inhomogeneity and coupling constant heterogeneity is determined by numerically extending the kernel formalism intro- duced by Herzog and Hahn to understand spin diffusion in solids. Finally, the merit of the numerical approach is tested by comparison with analytical results for homogeneous rf pulses and experimental results for perdeuterated nitrobenzene involving inhomogeneous rf pulses and coupling heterogeneity. 2001 John Wiley & Sons, Inc. Concepts Magn Reson 13: 171 189, 2001
Chronic morphine-induced loss of the facilitative interaction between vasoactive intestinal polypeptide and δ-opioid: involvement of protein kinase C and phospholipase Cβs

Abstract This laboratory recently demonstrated a multiplicative interaction between the pelvic visceral afferent transmitter vasoactive intestinal polypeptide (VIP) and the δ-opioid receptor (DOR)-selective agonist [ d -Pen2,5] enkephalin (DPDPE) to regulate cAMP levels in spinal cord [Brain Res. 959 (2003) 103]. Although DOR activation is required for the manifestation of the VIP–DPDPE facilitative interaction, its relevance to opioid antinociception remains unclear. The current study investigates whether or not the VIP–DPDPE facilitation of cAMP formation is subject to tolerance formation, a hallmark characteristic of opioid antinociception. Chronic morphine exposure abolishes the VIP–DPDPE facilitative interaction, consistent with its relevance to DOR antinociception. However, acute in vitro inhibition of protein kinase C (PKC) reinstates the VIP–DPDPE multiplicative interaction characteristic of opioid naive spinal tissue. This suggests that its chronic morphine-induced loss requires a PKC phosphorylation. PKC phosphorylation negatively modulates phospholipase C (PLC)β, enzymes intimately associated with phosphoinositide turnover and calcium trafficking. These are essential determinants of acute and chronic opioid effects. Accordingly, the effect of chronic morphine on their state of phosphorylation was also investigated. Central nervous system opioid tolerance is associated with the reciprocal phosphorylation (regulation) of two PLCβ isoforms, PLCβ1 and PLCβ3. However, although chelerythrine reinstates the chronic morphine-induced loss of the multiplicative VIP–DPDPE interaction, it does not alter the associated changes in PLCβ phosphorylation, possibly indicating different time courses of restitution of function and/or involvement of different kinases for different components of tolerance. These results could provide a mechanistic rubric for understanding positive modulation of opioid antinociception by afferent transmission.