cssi/SciSciGPT-SciSciNet huggingface dataset:
Emerging Technologies and the Advent of the Holocaust “Hologram”

Introduced in 2015, hologram-like recordings acquaint audiences with Holocaust survivors, survivors who soon no longer will be with us. Housed at various sites in the United States, from the United Nations to the Illinois Holocaust Museum and Education Center (IHME/Illionis), this emerging technology of Holocaust survivor “holograms” ensures survivors’ histories will “live.” What makes these recordings of Holocaust survivors innovative is that they are interactive. In response to visitors’ queries, the recordings are prepared to answer 1,000 possible questions. In addition, over time, the survivor recordings refine “their” answers to those questions by learning to better understand what is being asked and providing the best answer in their repository. The analysis conducted and conclusions reached in this paper are guided by the research question: What are the ethical concerns related to the development of this technology and the relationships it engenders? To that end, this paper interrogates the role played by the visitors who engage with the recordings and help to determine, via algorithms, the narratives the recordings tell; the importance of the human and ethical alliance created between the interlocutors who ask and the recordings that respond; and, lastly, the significance of these recordings to the survivors themselves. In order to conduct this research, the author conducted interviews and consulted first-hand accounts from the creators of these survivor recordings, the museum staff who have introduced visitors to the recordings, and the survivors themselves offered in news stories, publicity announcements, conference proceedings, and journal articles.
Algebraic and Geometric Methods in Statistics: The generalised shuttle algorithm

Bounds for the cell counts in multi-way contingency tables given a set of marginal totals arise in a variety of different statistical contexts including disclosure limitation. We describe the Generalized Shuttle Algorithm for computing integer bounds of multi-way contingency tables induced by arbitrary linear constraints on cell counts. We study the convergence properties of our method by exploiting the theory of discrete graphical models and demonstrate the sharpness of the bounds for some specific settings. We give a procedure for adjusting these bounds to the sharp bounds that can also be employed to enumerate all tables consistent with the given constraints. Our algorithm for computing sharp bounds and enumerating multiway contingency tables is the first approach that relies exclusively on the unique structure of the categorical data and does not employ any other optimization techniques such as linear or integer programming. We illustrate how our algorithm can be used to compute exact p-values of goodness-of-fit tests in exact conditional inference.
Mild Cognitive Impairment: Its Past, Present, and Future

As the baby boom generation nears retirement age and average life expectancy continues to rise, Alzheimer’s disease (AD) is quickly becoming one of the most relevant disorders of our time. There has been an increasing focus on early detection of AD for its various advantages from advanced planning to possible preventive treatment. As such, the main objective of this paper is to explore the transient stage between normal aging and dementia (centered on AD)—how its conceptualization has evolved throughout the past, present, and future. At the core lies the term “mild cognitive impairment” (MCI) as the paper traces its history, current standing, and topics of debate in the field. Its future implications as framed under the impending DSM-5 are discussed.
Acute leptin evokes physiological responses in rat carotid body type I cells (873.4)

Leptin is a central stimulant of respiration and also contributes to obesity related sympathoactivation. Recently leptin receptors have been identified on type I cells from the carotid body. Our most recent data indicate that activation of these receptors with leptin initiates calcium signaling events and increases outward macroscopic currents in isolated type I cells. The acute (10 min) application of leptin (200 ng.ml-1) evoked calcium signaling responses in isolated type I cells. Cells significantly increased their Fura 2 F340/F380 ratio by 0.09 ± 0.015 ratio units (n =24, P < 0.001). Leptin also increased the peak membrane currents in a subset (65%) of type I cells. At +10mV leptin (200ng.ml-1) increased peak macroscopic currents from 123 ± 19 pA.pF-1 to 198 ± 28 pA.pF-1 (n = 6, P < 0.02). The remaining 35% of type I cells were unresponsive to this concentration of leptin. Interestingly, leptin does not alter the rate of oxidative phosphorylation in isolated type I cells as measured by reduction of C1...
Regulation of the Bacillus subtilis pyrimidine biosynthetic operon by transcriptional attenuation: control of gene expression by an mRNA-binding protein.

The pyrimidine nucleotide biosynthetic (pyr) operon of Bacillus nubtilin is regulated by a transcriptional attenuation mechanism in which termination of transcription at points upstream of the genes being regulated is promoted by the binding of a regulatory protein, PyrR, to specific sequences in the pyr mRNA. Binding of PyrR to pyr mRNA is stimulated by uridine nucleotides and causes changes in the mRNA secondary structure. This model is supported by extensive molecular genetic analysis. PyrR, which is encoded by the first gene of the pyr operon, is also a uracil phosphoribosyltransferase, although it has little amino acid sequence resemblance to other bacterial uracil phosphoribosyl transferases. Purified B. Subtlis pyrR promotes attenuation of pyr transcription in vitro and binds specifically to pyr RNA sequences. The crystallographic structure of PyrR demonstrates the similarity of its tertiary structure to other phosphoribosyltransfe rases and suggests the surface to which RNA binds. PyrR is widely distributed among eubacteria and appears to regulate pyr genes not only by the attenuation mechanism found in B. subtilix, but also by a coupled transcription-translation attenuation mechanism and by acting as a translational repressor. PyrR illustrates the concept that transcriptional attenuation is a much more widespread and mechanistically versatile mechanism for the regulation of gene expression in bacteria than is generally recognized.
Arthropod-Borne Diseases: The Camper's Uninvited Guests

Arthropod-borne diseases are a major problem whenever outdoor activities bring arthropods and people into contact. The arthropods discussed here include arachnids (ticks) and insects. Most arthropod bites and stings are minor, with the notable exception being bee-sting anaphylaxis. Ticks cause the most disease transmission. Key hard tick vectors include black-legged (Ixodes), dog (Dermacentor), and lone star (Amblyomma) ticks, which transmit Lyme and various rickettsial diseases. Insect repellents, permethrin sprays, and proper tick inspection reduce this risk significantly. Lyme disease and the milder southern-tick-associated rash illness (STARI) are characterized by the erythema migrans rash followed, in the case of Lyme disease, by early, disseminated, and late systemic symptoms. Treatment is with doxycycline or ceftriaxone. Indefinite treatment of "chronic Lyme disease" based on subjective symptoms is not beneficial. Rickettsial diseases include ehrlichiosis, anaplasmosis, and Rocky Mountain spotted fever, which are characterized by fever, headache, and possible rash and should be empirically treated with doxycycline while awaiting laboratory confirmation. Tularemia is a bacterial disease (Francisella) spread by ticks and rabbits and characterized by fever and adenopathy. Treatment is with gentamicin or streptomycin. Babesiosis is a protozoal disease, mimicking malaria, that causes a self-limited flu-like disease in healthy hosts but can be life threatening with immune compromise. Treatment is with atovaquone and azithromycin. Other tick-related conditions include viral diseases (Powassan, Colorado tick fever, heartland virus), tick-borne relapsing fever (Borrelia), and tick paralysis (toxin). Mosquitoes, lice, fleas, and mites are notable for their annoying bites but are increasingly significant disease vectors even in the United States.
Program CICC, flow and heat transfer in cable in conduit conductors

The computer program CICC has been written for use in the thermofluids design of superconducting magnets for tokamak reactors, which use forced-flow, helium-cooled, cable-in-conduit conductors (CICC). In addition to background heat loads that vary with space and time, these superconductors can develop normal zones that generate electrical resistance heat. Program CICC models the transient thermodynamic and fluid-dynamic system response to background heating and normal-zone propagation in the superconductor. The computational algorithm described couples a one-dimensional, compressible pipe-flow model (including flow choking) with two-dimensional, axisymmetric, heat-conduction models of the superconductor cable, the conduit and the epoxy-conduit insulation. National Institute of Standards and Technology helium properties are used. The model is verified by comparison with measured temperature and pressure profiles from thermal expulsion experiments. >
User experience modeling and enhancement for virtual environments that employ wide-field displays

User experience in virtual environments including presence, enjoyment, and Simulator Sickness (SS) was modeled based on the effects of field-of-view (FOV), stereopsis, visual motion frequency, interactivity, and predictability of motion orientation. We developed an instrument to assess the user experience using multivariate statistics and Item Response Theory. Results indicated that (1) presence was increased with a large FOV, stereo display, visual motion in low frequency ranges (.03 Hz), and high levels of interactivity; (2) more SS was reported with increasing FOV, stereo display, .05-.08 Hz visual motion frequency, lack of interactivity and predictability to visual motion; (3) enjoyment was increased with visual motion in low frequency ranges (.03 Hz) and high levels of interactivity. The resulting response surface model visualizes the complex relationships between presence, enjoyment, and SS. Overall, increasing interactivity was found to be the most profound way to enhance user experience in virtual environments.
Large-Scale Structure, Peculiar Velocities and the Density Field in the Local Universe

Peculiar Velocity Field Peculiar velocities of galaxies, i.e. devitions from smooth Hubble flow, are thought to arise from inhomogeneities in the matter distribution. The amplitude of those velocities is regulated by the spatial scale and the amplitude of the matter density irregularities as well as by the value of the mean matter density. The direct measurement of peculiar velocities thus provides a means to infer the characteristics of the mass distribution, luminous and dark, in the universe and cosmological parameters such as Ω0. Conversely, the distribution of luminous matter (i.e. galaxies) and fair assumptions on the nature of biasing can be used to obtain an estimate of the peculiar velocity field. In the first lecture of this series of three, the relationships between the matter density and peculiar velocity fields will be surveyed. In doing so we heavily borrow from Peebles (1993) and Strauss and Willick (1995). We will also explore the estimates of the peculiar velocity field resulting from photometric and redshift catalogs of galaxies and clusters of galaxies. In the second lecture, we will review the methods most commonly used for the direct measurement of peculiar velocities, with emphasis on the Tully—Fisher (1977) relation (hereafter TF), and in lecture 3 we will concentrate on the results of those measurements and their implications for the determination of the density field and parameters of cosmological interest.
Stress behavior of electroplated Sn films during thermal cycling

The mechanical behavior of electroplated Sn thin films was investigated using thermal-expansion induced strain. For stress above a threshold value, the stress relaxation observed during the thermal cycles is well-described by a power law creep mechanism with exponents similar to those of the bulk material. However, the stress relaxation showed significant thickness dependence so that the relaxation in thicker films is faster than thinner films. The surface oxide was also shown to have a considerable effect on retarding the relaxation by inhibiting diffusion to the surface. The relevance of the stress relaxation to whisker formation in Sn-based coatings is discussed.
Percutaneous Transluminal Coronary Angioplasty: Role of the Surgeon

Over a recent one-year period, 339 patients underwent percutaneous transluminal coronary angioplasty (PTCA) and were compared with 338 patients having isolated coronary artery bypass surgery. Patients undergoing PTCA had a shorter duration of angina, a lower number of prior myocardial infarctions, and better left ventricular function (p less than 0.01); PTCA was considered initially successful in 87% (295/339) of patients. Repeat angioplasty was performed in 18% of patients (34/339), with a successful outcome in all but 1. The most common finding at operation in those with failed angioplasty and urgent or emergency revascularization was dissection of an atheromatous plaque. There were 28 early failures (operation performed within 24 hours) and 24 late failures (operation at more than 24 hours), for early and late failure rates of 8.3% and 7.1%, respectively. Although the cumulative frequency of new Q-waves in the entire angioplasty series was low (2.7%), the incidence was high in those with angioplasty failure and subsequent operation (18%), and was significantly greater than in patients having elective coronary bypass (3.6%). Use of inotropic agents and lidocaine treatment for ventricular arrhythmias was also significantly higher in patients with unsuccessful PTCA who required operation than in those undergoing elective bypass (10% versus 3% and 10% versus 1.5%, respectively; p less than 0.01). Eleven of the 28 patients who were early failures were totally revascularized within 2 hours of angioplasty failure. Facilities and staff available for expedient revascularization accounted for the low morbidity and lack of mortality in PTCA failures.
Confidence-based dynamic ensemble for image annotation and semantics discovery

Providing accurate and scalable solutions to map low-level perceptual features to high-level semantics is critical for multimedia information organization and retrieval. In this paper, we propose a confidence-based dynamic ensemble (CDE) to overcome the shortcomings of the traditional static classifiers. In contrast to the traditional models, CDE can make dynamic adjustments to accommodate new semantics, to assist the discovery of useful low-level features, and to improve class-prediction accuracy. We depict two key components of CDE: a multi-level function that asserts class-prediction confidence, and the dynamic ensemble method based upon the confidence function. Through theoretical analysis and empirical study, we demonstrate that CDE is effective in annotating large-scale, real-world image datasets.
Cognitive and Motivational Characteristics of Adolescents Gifted in Mathematics: COmparisons Among Students With Different Types of Giftedness

Although numerous studies have compared cognitive and motivational characteristics between gifted versus nongifted students, research comparing those characteristics among different types of gifted students has not kept up with the theoretical development that saw a transition from unidimensional to multidimensional conceptualizations of giftedness. This study compares cognitive and motivational characteristics of high school students who are academically gifted in math, creatively talented in math, and nongifted. Whereas no differences were found among the three groups in their beliefs about ability, most of the other characteristics examined in the study distinguished the three groups. Academically gifted female students reported expending more effort than did academically gifted male students. Creatively talented males put forth more effort than academically gifted males, and the creatively talented in general used more cognitive strategies than the academically gifted. Overall, students who were eithe...
Breed-dependent susceptibility to acute sound exposure in young chickens.

Abstract Commercially available chickens fall into two categories: egg layers and broilers. Durham et al. (Hear. Res. 166 (2002) 82–95) showed that despite similar noisy living environments, cochleae of most adult broilers show extensive damage, while cochleae of adult egg layers are largely normal. This finding suggests that egg layers and broilers differ in their susceptibility to noise damage. Here, we evaluate breed differences in susceptibility to acoustic trauma. Young egg layers and broilers (10–17 weeks) were exposed to a 1500 Hz pure tone (120 dB SPL; 24 h) and killed 24 or 72 h later. Cochleae were prepared for scanning electron microscopy and photomicrographs of the cochlear surface were used to determine location and severity of damage. Cochleae were grouped based upon damage severity (moderate or severe). While location and area of damage were similar between both breeds at each recovery time, cochlear damage at 72 h was more extensive than at 24 h. We found no quantitative breed differences within either damage category or recovery time. However, more egg layers (25/27) than broilers (16/32) displayed severely damaged cochleae. Our findings conflict with those reported by Durham et al. (2002). Our results identify a breed-dependent difference in susceptibility to acute sound exposure, with young egg layers displaying increased sensitivity.
Integrity of blood-brain barrier to peroxidase in senescent mice

Abstract The brain distribution of systemically-administered horseradish peroxidase was studied in senescent mice and compared with the distributionin a group of young mice. The distribution of HRP was surveyed in both the experimental and control groups by light and electron microscopy by an observer unaware of the source of the material. No qualitative differences were observed in the brain distribution of systemically-administered HRP in old mice compared to young mice. The results of this study suggest that the blood-brain barrier to HRP is preserved in senescent mice.
TRANSGENIC OVEREXPRESSION OF GLUCOSE TRANSPORTERS PREVENTS DIET-INDUCED INSULIN RESISTANCE AND GLUCOSE INTOLERANCE IN MICE. • 540

TRANSGENIC OVEREXPRESSION OF GLUCOSE TRANSPORTERS PREVENTS DIET-INDUCED INSULIN RESISTANCE AND GLUCOSE INTOLERANCE IN MICE. • 540
Food and nutrient intake of 6- to12-month-old infants fed formula or cow milk: A summary of four national surveys

Food and nutrient intakes of infants during the second 6 months of life were summarized with the use of four national surveys as the data base. Three of the surveys, the second National Health and Nutrition Examination Survey (1976–1980), the Ross Nutrition Survey (1984), and the U.S. Department of Agriculture Nationwide Food Consumption Survey (1977–1978), summarized and compared the nutrient composition of the diets of infants fed formula with that of the diets of infants fed cow milk during the second 6 months of life. The Gerber Nutrition Survey (GNS) summarized the nutrient composition of the diets of infants fed formula, cow milk, or human milk, or a combination of these, during 1986. Iron-fortified formula with belkost provided adequate but not excessive intakes of all nutrients for infants during the second 6 months of life with the possible exception of calcium for older infants. In contrast to cow milk, formula provided readily absorbed and adequate iron, generous linoleic acid, and adequate but not excessive intakes of protein, phosphorus, sodium, and potassium. The distribution of energy between protein, carbohydrate and fat, and potential renal solute load was reasonable in infants fed formula. Cow milk with beikost provided low intakes of readily bioavailable iron and linoleic acid and high intakes of protein, calcium, phosphorus, sodium, potassium, and potential renal solute load during the second 6 months of life. The diets of infants fed low-fat milks were even lower in linoleic acid and higher in volume of food consumed, protein, calcium, phosphorus, sodium, potassium, and potential renal solute load than the diets of infants fed whole cow milk. Apparently, infants fed cow milk were treated differently than those fed formula (i.e., they were given more solids and table foods and less baby food at all ages and less volume of milk at 9 and 12 months of age). These data provided the basis for the development of practical suggestions for feeding infants during the second 6 months of life.
Analysis of surface sputtering on a quantum statistical basis

Surface sputtering is explained theoretically by means of a 3-body sputtering mechanism involving the ion and two surface atoms of the solid. By means of quantum-statistical mechanics, a formula for the sputtering ratio S(E) is derived from first principles. The theoretical sputtering rate S(E) was found experimentally to be proportional to the square of the difference between incident ion energy and the threshold energy for sputtering of surface atoms at low ion energies. Extrapolation of the theoretical sputtering formula to larger ion energies indicates that S(E) reaches a saturation value and finally decreases at high ion energies. The theoretical sputtering ratios S(E) for wolfram, tantalum, and molybdenum are compared with the corresponding experimental sputtering curves in the low energy region from threshold sputtering energy to 120 eV above the respective threshold energy. Theory and experiment are shown to be in good agreement.
Iranian STR variation at the fringes of biogeographical demarcation

The integrative relationship between population genetics and forensic biology allows for a thorough genetic characterization of extant human populations. This study aimed to genetically characterize 150 unrelated healthy donors from a general population in Iran both forensically and phylogenetically. The allelic frequencies of 15 STR loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818 and FGA) were generated. This constitutes the core of polymerase chain reaction (PCR)-based DNA genetic markers in the US Combined DNA Index System (CODIS) plus two additional loci (D2S1338 and D19S433) that together are consistent with several other worldwide database requirements. There were no deviations from Hardy-Weinberg expectations. Based upon the allelic frequencies, several important forensic parameters were calculated including: gene diversity (GD) index, power of discrimination (PD), polymorphic information content (PIC) and power of exclusion (PE). G-tests indicate the allelic frequencies of the Iranians are statistically non-significant compared to two Turkish populations yet, statistically different from the remaining 18 groups obtained from the literature and examined in this study. This suggests that the Iranian dataset may be forensically equivalent to the dataset from the Turkish region of Eastern Anatolia and the general population from Turkey. Phylogenetic analysis of our population with the full set of 15 loci indicate the Iranians occupy an intermediate position relative to the major Caucasian and East Asian clades on a global level. A regional phylogenetic analysis using 13 of the 15 loci indicate the Iranians segregate in a more compact association with groups from southeastern Spain, Arabs from Morocco and Syria, and especially with the general population from Turkey and those from Eastern Anatolia. These groups are flanked by highly differentiated populations from northern India and a Berber group from Tunisia on opposing ends of the regional phylogram. This report also demonstrates the necessity to thoroughly characterize the genetic composition of populations located in geographic intersections in order to choose the appropriate dataset on which to base forensic calculations, not only at an intra-population level, but also at an inter-population level as well.
MDMA-induced neurotoxicity: parameters of degeneration and recovery of brain serotonin neurons.

Abstract This study investigates a number of parameters that influence the neurotoxic effects of 3,4-methylenedioxymethamphetamine (MDMA) on serotonin (5-HT) neurons in brain. Both the dose and number of injections of MDMA affect the degree of neurotoxicity on 5-HT axons and terminals as assessed by decreases in the content of 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) and the density of 5-HT uptake sites. Repeated systemic administration of various doses of MDMA (5–20 mg/kg twice daily for 4 consecutive days) results in dose-dependent decreases in 5-HT, 5-HIAA and 5-HT uptake sites. Increasing the number of injections of MDMA resulted in progressively greater reductions in 5-HT and 5-HIAA which occurred prior to decreases in 5-HT uptake sites. In contrast, no significant changes were observed in the density of norepinephrine uptake sites following single or repeated injections of 20 mg/kg MDMA. With respect to neuronal regeneration, following an initial 90% loss of 5-HT uptake sites after treatment with MDMA, the recovery of these sites occurred over a protracted period of time; a marked 25% reduction was seen at 6 months and the concentration of 5-HT uptake sites returned to control levels at 12 months following treatment with MDMA. Pretreatment with the selective 5-HT uptake blocker, citalopram, prior to each injection of MDMA prevented the neurotoxic effects of MDMA on the 5-HT parameters described above suggesting that active uptake of MDMA or a MDMA-related substance into brain 5-HT neurons was involved in the neurotoxic actions of the drug. In addition, the neurodegenerative effects of MDMA on 5-HT neurons exhibited some species specificity as comparable decreases in cerebral cortical 5-HT, 5-HIAA and 5-HT uptake sites were observed in rat and guinea pig while no significant changes in any of these serotonergic parameters were seen in mouse brain.
Regional welfare program and labour force participation

. This paper investigates regional variations in household welfare program and labour force participation behaviour in the United States. A choice-theoretic model is developed and estimated for each of the major census regions (Northeast, Midwest, South and West) using cross-section data on households, labour markets, and state policies. We show how the observable heterogeneity across U.S. census regions explains different welfare program participation and workforce outcomes. We find little evidence of differences in behaviour with respect to welfare program policies across regions. This finding undermines some of the efficiency rationale for the devolution of authority over welfare programs to the states. We also find evidence that welfare program participation still reduces labour supply in some regions. That finding supports the incentive rationale for the imposition of work requirements. Abstract. Este articulo investiga las variaciones regionales en un programa de asistencia social para hogares y comportamiento de participacion de mano de obra en los Estados Unidos. Para cada una de las principales regiones censuales (noreste, medio oeste, sur y oeste) se desarrolla y estima un modelo de teoria de la eleccion usando datos transversales sobre hogares, mercados de mano de obra, y politicas estatales. Mostramos como la heterogeneidad observable en las regiones censuales estadounidenses explican las diferencias en la participacion en programas de asistencia social y en los resultados para la mano de obra. Encontramos escasa evidencia de diferencias en comportamiento entre regiones con respecto a politicas de programas de asistencia social. Este hallazgo pone en duda parte del argumento de eficacia de la devolucion a los estados de la competencia en programas de asistencia social. Tambien hallamos evidencia de que la participacion en programas de asistencia social todavia reduce la oferta de mano de obra en algunas regiones. Dicho hallazgo apoya el argumento del incentivo en la imposicion de obligacion de trabajar.
Controlled Activity Polymers. V. Copolymers of 2-(1-Naphthylacetyl) Ethyl Acrylate with Hydrophilic Comonomers: Release Behavior

Abstract Release properties of the copolymers of 2-(1-naphthylacetyl)ethyl acrylate with hydrophilic comonomers of known molecular weight have been studied as a function of pH, composition, comonomer type, and copolymer microstructure. Fluorescence and solid-state 13C-NMR studies have also been performed. Neighboring group effects for the hydrolysis were observed by the concentration of auxin released; the release mechanism differed with the comonomer type. In addition, the release behavior of the ionic copolymers is affected by the presence of intramolecular hydrophobic interactions.
Experience With Computer Generation and Scoring of Tests for a Large Class

In an introductory psychology class of size 200, a computer-based testing and scoring system was tried out. Individual test forms were generated by a random process from an item pool and were printed by computer; test-response data were scored by computer; and test-score records for each student were maintained by computer. Advantages included: (1) increased frequency of tests, (2) immediacy of feedback, (3) accessibility and currency of cumulative records, (4) decreased opportunities for cheating, (5) decrease in difliculties and extra work associated with retests and make-up examinations, (6) decreased need for typing and secretarial services, (7) shortened lead time between initial stages of test preparation and administration, and (8) autonomy of the process, as it required little high-level decision making once in progress. Cost analysis indicated that such a system would be feasible for adoption by an individual instructor, given the required facilities at the university computer installation.
Retinal progenitor cells--timing is everything.

Permitting progenitor photoreceptor cells from donors to differentiate before transplanting them is key to their successful integration into the retina.
Murine adenovirus infection of SCID mice induces hepatic lesions that resemble human Reye syndrome.

Abstract Murine adenovirus type 1 (MAV-1) infection of CB-17 SCID mice (which are homozygous for the severe combined immunodeficiency mutation) induces hepatic histopathologic and ultrastructural features that are strikingly similar to human Reye syndrome. Gross pathologic examination of MAV-1-infected mice revealed only pale yellow liver tissue. Histopathologic studies of tissue from MAV-1-infected mice revealed diffuse hepatic injury manifested by microvesicular fatty degenerative changes of hepatocytes and electron microscopic evidence of focal mitochondrial swelling with disruption of cristae and depletion of glycogen. Serum aminotransferase activities increased markedly in the infected animals; however, plasma ammonia levels were not elevated at the times assayed. Although all mice infected with MAV-1 died, neutralizing anti-MAV-1 monoclonal antibodies provided a dose-dependent delay in the appearance of clinical disease and hepatic histopathologic findings. Other findings included rare viral inclusions with only minimal inflammation in spleen, adrenal, and liver of infected mice. Our findings indicate that MAV-1 infection of SCID mice may provide important insights into the pathogenesis of the hepatic lesions of Reye syndrome.
Distribution Kinetics Model for the Sol−Gel Transition Critical Exponent

The pregelation weight-average molecular weights of cross-linked polymers and silica-based sol−gels diverge at the sol−gel transition, where time t approaches the gel time tc. The divergence follows a power law, (1 − t/tc)-γ, with a critical exponent larger than the γ = 1 prediction of classic Flory−Stockmayer theory and of our previous cross-linking model. In this paper we modify the cross-linking mechanism by allowing a fractional exponent, 0 < ω ≤ 1, for the mass-dependent rate kernel to match the critical exponents of real systems. Moment equations solved by closure approximations show that γ is determined solely by ω, in agreement with an existing analytical solution. The rate constants for cross-linking, addition, and condensation polymerization have essentially no effect on γ. We also obtained for the first time an analytical expression for gel time, in agreement with moment closure solutions for values of ω other than 0 or 1. When ω is either 3/4 or 5/6, good approximations to experimental values ...
A Convenient, High-Yield Preparation of Butadiene-2,3-Dicarboxylic Acid (Fulgenic Acid)

Abstract Butadiene-2, 3-dicarboxylic acid (fulgenic acid) has been reported previously to be avaialable in ca. 1% yield following basic hydrolysis of the corresponding dimethyl ester.1
Carrier-mediated transport of vasopressin across the blood-brain barrier of the mouse.

A brain to blood carrier-mediated transport system for arginine vasopressin (AVP) was investigated in mice after intraventricular injection of iodinated AVP and varying amounts of unlabeled material or candidate inhibitors. Residual activity in the brain detected after decapitation was used as the main determinant of transport activity. The half-time disappearance of iodinated AVP from the brain was 12.4 min, the Vmax was 1.41 nmol/g-min, and the apparent Km was 28.7 nmol/g. A 30-nmol dose of AVP, mesotocin, arginine vasotocin, pressinoic amide, pressinoic acid, tocinoic acid, and lysine vasotocin, but not oxytocin, lysine vasopressin, AVP free acid, tocinoic amide, Tyr-MIF-1, or cyclo Leu-Gly, significantly (P less than 0.05) inhibited the transport of iodinated AVP out of the brain. The 30 nmol dose of AVP had no effect on the transport of iodide or iodotyrosine out of the brain. High-performance liquid chromatography showed that 59.2% of the radioactivity found in the blood 2 min after an i.c.v. injection of labeled AVP eluted at the same position as labeled AVP compared with 68.8% of radioactivity eluting at that position after material was infused i.v. for 2 min. This indicates that intact peptide is transported across the blood-brain barrier and that most of the degradation of AVP occurs during circulation in the blood. Calculations based on the appearance of radioactivity in the periphery showed that 56.2% of the material injected centrally would have been transported into the periphery by 10 min. This appearance of material in the periphery was inhibited by the simultaneous injection of an excess of unlabeled peptide. Water loading significantly decreased the brain to blood transport rate of AVP by 40%. It is concluded that a saturable system exists for brain to blood transport of AVP and some structurally similar peptides.
Demonstration of presynaptic protein kinase C activation following long-term potentiation in rat hippocampal slices

Pharmacological and biochemical evidence implicate the Ca2+ and phospholipid-dependent protein kinase C in long-term potentiation. The in vitro hippocampal slice preparation was used to demonstrate redistribution of protein kinase C from cytosol to membrane and protein kinase C-dependent phosphorylation of the presynaptic growth-associated protein-43 substrate following long-term potentiation induction in area CA1. Protein kinase C translocation was assessed using both quantitative immunoblotting with a monoclonal antibody recognizing a common epitope in the alpha and beta isoforms of protein kinase C and Ca2+ and phospholipid-dependent phosphorylation of exogenous histone substrate. Slices examined 5 min after tetanus-induced spike potentiation showed no change in protein kinase C redistribution, whereas slices examined at 15-, 30- and 60-min intervals all showed a similar degree of protein kinase C translocation to membrane, although only at 15 min was the effect statistically significant. Additionally, an increase in protein kinase C-dependent growth-associated protein 43 phosphorylation was observed 10 min after high-frequency stimulation. The translocation of protein kinase C and phosphorylation of growth-associated protein 43 were dependent upon high-frequency (repetitive 400 Hz) afferent stimulation, as no effects were observed in slices receiving low-frequency (1 Hz) or no stimulation. The N-methyl-D-aspartate receptor antagonist, DL-2-amino-5-phosphonovaleric acid (50 microM), inhibited induction of long-term potentiation, redistribution of protein kinase C and phosphorylation of growth-associated protein 43. A significant redistribution of the predominantly presynaptic protein kinase C isoform, protein kinase C-alpha, was also detected 15 min after induction of long-term potentiation using an alpha-isoform-specific monoclonal antibody. These observations support a presynaptic role for protein kinase C and growth-associated protein 43 in the early maintenance phase of LTP, and further suggest that a retrograde messenger produced postsynaptically following N-methyl-D-aspartate receptor activation mediates these effects.
Algorithm for optimal winner determination in combinatorial auctions

Combinatorial auctions, that is, auctions where bidders can bid on combinations of items, tend to lead to more efficient allocations than traditional auction mechanisms in multi-item auctions where the agents' valuations of the items are not additive. However, determining the winners so as to maximize revenue is NP-complete. First, we analyze existing approaches for tackling this problem: exhaustive enumeration, dynamic programming, and restricting the allowable combinations. Second, we study the possibility of approximate winner determination, proving inapproximability in the general case, and discussing approximation algorithms for special cases. We then present our search algorithm for optimal winner determination. Experiments are shown on several bid distributions which we introduce. The algorithm allows combinatorial auctions to scale up to significantly larger numbers of items and bids than prior approaches to optimal winner determination by capitalizing on the fact that the space of bids is sparsely populated in practice. The algorithm does this by provably sufficient selective generation of children in the search tree, by using a secondary search for fast child generation, by using heuristics that are admissible and optimized for speed, and by preprocessing the search space in four ways. Incremental winner determination and quote computation techniques are presented.
Absorption and distribution in rats of radioactive phosphorus biologically incorporated in food.

IN this investigation absorption and distribution of phosphorus-32, biologically incorporated into fish muscle and bean leaves, was compared with its absorption after feeding as inorganic phosphate. Within limits of error, no differences were detected.
Broken Heart Syndrome, Neurogenic Stunned Myocardium and Stroke

The diagnosis of stress cardiomyopathy is often made during coronary angiography. At this point hemodynamic parameters should be assessed; a right heart catheterization with measurement of cardiac output by Fick and thermodilution methods is helpful. Patients with acute neurologic pathology who develop left ventricular dysfunction (neurogenic stunned myocardium) may not be candidates for coronary angiography and in such cases real-time myocardial contrast echocardiography or nuclear perfusion scan can be used to exclude obstructive coronary disease. Hypotension and shock can be due to low output state or left ventricular outflow tract obstruction. Low output state can be managed with diuretics and vasopressor support. Refractory shock and/or severe mitral regurgitation may require an intra-aortic balloon pump for temporary support. In patients with intraventricular gradient intravenous beta-blockers have been used safely. Hemodynamically unstable patients should be managed in a critical care unit and stable patients should be monitored on a telemetry unit as arrhythmias may occur. An echocardiogram should be performed to look for intraventricular gradient, mitral regurgitation, or left ventricular thrombus. If left ventricular thrombus is seen or suspected anticoagulation with warfarin or low molecular weight heparin is generally advised until recovery of myocardial function and resolution of thrombus occurs. In patients with subarachnoid hemorrhage the use of vasopressors to reduce cerebral vasospasm may worsen left ventricular outflow tract gradient. In hemodynamically stable patients, a beta-blocker or combined alpha/beta blocker should be initiated. Myocardial function generally recovers within days to weeks with supportive treatment in most patients. The use of a standard heart failure regimen including an angiotensin-converting enzyme inhibitor or aldosterone receptor antagonist, beta-blocker titrated to maximal dose, diuretics, and aspirin is common until complete recovery of myocardial function occurs. Chronic therapy with a beta-blocker may be advisable. The underlying diagnosis that precipitated stress cardiomyopathy such as critical illness, neurologic injury, or medication exposure should be identified and treated.
Accounting for electronic polarization in non-polarizable force fields

The issues of electronic polarizability in molecular dynamics simulations are discussed. We argue that the charges of ionized groups in proteins, and charges of ions in conventional non-polarizable force fields such as CHARMM, AMBER, GROMOS, etc should be scaled by a factor about 0.7. Our model explains why a neglect of electronic solvation energy, which typically amounts to about a half of total solvation energy, in non-polarizable simulations with un-scaled charges can produce a correct result; however, the correct solvation energy of ions does not guarantee the correctness of ion–ion pair interactions in many non-polarizable simulations. The inclusion of electronic screening for charged moieties is shown to result in significant changes in protein dynamics and can give rise to new qualitative results compared with the traditional non-polarizable force field simulations. The model also explains the striking difference between the value of water dipole μ ∼ 3D reported in recent ab initio and experimental studies with the value μeff ∼ 2.3D typically used in the empirical potentials, such as TIP3P or SPC/E. It is shown that the effective dipole of water can be understood as a scaled value μeff = μ/√eel, where eel = 1.78 is the electronic (high-frequency) dielectric constant of water. This simple theoretical framework provides important insights into the nature of the effective parameters, which is crucial when the computational models of liquid water are used for simulations in different environments, such as proteins, or for interaction with solutes.
Methodological Issues in the Classification of Attention-Related Disorders

The classification and identification of children with attention deficit-hyperactivity disorder and related disorders involving learning and behavior are only rudimentarily developed. A major problem is the substantial overlap among children with attention, learning, and behavioral problems. The science of classification provides conceptual and methodological approaches addressing these problems. For successful classification of these children, major issues include (a) the need to provide explicit studies of identification criteria, (b) the need for systematic sampling strategies, (c) development of hypothetical classifications, and (d) systematic assessment of reliability and validity of hypothetical classifications. With the methodological advances provided by classification-oriented research, investigators and practitioners may be able to address issues involving definition and identification of children with attention and related disorders.
Flavin conformational changes in the catalytic cycle of p-hydroxybenzoate hydroxylase substituted with 6-azido- and 6-aminoflavin adenine dinucleotide.

Crystallographic studies have demonstrated two flavin conformations for p-hydroxybenzoate hydroxylase (PHBH) [Gatti, D. L., Palfey, B. A., Lah, M. S., Entsch, B., Massey, V., Ballou, D. P., & Ludwig, M. L. (1994) Science 266, 110−114. Schreuder, H. A., Mattevi, A., Obmolova, G., Kalk, K. H., Hol, W. G. J., van der Bolt, F. J. T., & van Berkel, W. J. H. (1994) Biochemistry 33, 10161−10170]. The isoalloxazine ring system of one conformation (the “out” conformation) is significantly more exposed to solvent and is not in position for necessary catalytic reactions, but when the natural substrate is bound to the enzyme, the isoalloxazine is in the correct position (the “in” conformation) for its chemical function. In this study, several aspects of the function of the conformational change in catalysis were explored using the wild-type and Tyr222Phe forms of PHBH substituted with 6-azido FAD. This flavin served as both a spectral probe and a photolabel. The enzyme containing 6-azido FAD was a relatively effectiv...
A General Theory of Systems of Electric and Magnetic Units

A system of electric and magnetic units may be shown to be characterized by five parameters, namely: a numeric, n, which gives the ratio between the density of electric displacement used in that system and the so-called theoretical density; a numeric, p, which gives the corresponding ratio for magnetic flux densities; a physical conversion factor, k, which converts a given volume of current into the corresponding magnetomotive force; the absolute permittivity, ?; and the absolute permeability, ?. On the basis of these five parameters, the principal fundamental equations of electricity, magnetism, and electromagnetic waves are written in what the author calls the general system of units, without assigning definite values to these parameters. He also shows that the five parameters must satisfy the equation vk = ?np/??, where v is the velocity of propagation of electromagnetic waves in that particular medium to which ? and ? refer; otherwise the five parameters may be chosen arbitrarily. By giving these parameters specific values, seven different systems of units are derived, namely, the electrostatic, the electromagnetic, the practical, the Gauss system, the Heaviside-Lorentz system, one which the author calls the compromise system, and the ampere-ohm system introduced by him some twenty years ago. The characteristics, the advantages, and the disadvantages of each system are briefly discussed, and it is shown how to deduce a new system of units from the general system, to conform to certain desired specifications.
Influence of the renal artery ostium flow diverter on hemodynamics and atherogenesis

The structure and function of the renal artery ostium flow diverter on the caudal side of the renal branch point were previously reported; in this study, we further evaluate the diverter׳s possible functions. The protrusion of this structure into the abdominal aorta suggests that the diverter may preferentially direct blood flow to the renal arteries, and that it may also influence flow patterns and recirculation known to be involved in atherogenesis. Three-dimensional computational fluid dynamics (CFD) simulations of steady and pulsatile blood flow are performed to investigate the influence of diverter size and position, and vascular geometry, on the flow patterns and fluid mechanical forces in the neighborhood of the diverter. CFD results show that the flow diverter does affect the blood distribution; depending on the diverter׳s position, the flow to the renal arteries may be increased or reduced. Calculated results also demonstrate the diverter׳s effect on the wall shear stress (WSS) distribution, and suggest that the diverter contributes to an atherogenic environment in the abdominal aorta, while being atheroprotective in the renal arteries themselves. These results support previous clinical findings, and suggest directions for further clinical study. The results of this work have direct implications in understanding the physiological significance of the diverter, and its potential role in the pathophysiological development of atherosclerosis.