cssi/SciSciGPT-SciSciNet huggingface dataset:
Flavin binding by bacterial luciferase: affinity chromatography of bacterial luciferase.

Abstract Immobilized FMN covalently attached to Sepharose-6B-hexanoate binds bacterial luciferase. Immobilized flavin is also effective in its reduced form as a substrate in the light emitting reaction catalyzed by luciferase.
Data preparation and interannotator agreement: BioCreAtIvE Task 1B

We prepared and evaluated training and test materials for an assessment of text mining methods in molecular biology. The goal of the assessment was to evaluate the ability of automated systems to generate a list of unique gene identifiers from PubMed abstracts for the three model organisms Fly, Mouse, and Yeast. This paper describes the preparation and evaluation of answer keys for training and testing. These consisted of lists of normalized gene names found in the abstracts, generated by adapting the gene list for the full journal articles found in the model organism databases. For the training dataset, the gene list was pruned automatically to remove gene names not found in the abstract; for the testing dataset, it was further refined by manual annotation by annotators provided with guidelines. A critical step in interpreting the results of an assessment is to evaluate the quality of the data preparation. We did this by careful assessment of interannotator agreement and the use of answer pooling of participant results to improve the quality of the final testing dataset. Interannotator analysis on a small dataset showed that our gene lists for Fly and Yeast were good (87% and 91% three-way agreement) but the Mouse gene list had many conflicts (mostly omissions), which resulted in errors (69% interannotator agreement). By comparing and pooling answers from the participant systems, we were able to add an additional check on the test data; this allowed us to find additional errors, especially in Mouse. This led to 1% change in the Yeast and Fly "gold standard" answer keys, but to an 8% change in the mouse answer key. We found that clear annotation guidelines are important, along with careful interannotator experiments, to validate the generated gene lists. Also, abstracts alone are a poor resource for identifying genes in paper, containing only a fraction of genes mentioned in the full text (25% for Fly, 36% for Mouse). We found that there are intrinsic differences between the model organism databases related to the number of synonymous terms and also to curation criteria. Finally, we found that answer pooling was much faster and allowed us to identify more conflicting genes than interannotator analysis.
Equilibrium studies of the direct reduction of sulphur dioxide by coal

Abstract The direct reduction of sulphur dioxide to elemental sulphur using coal has been studied utilizing models that simulate thermodynamic equilibrium. Comparison has been made between the computer models and process results. The results of the analysis indicate a discrepancy which may be attributable to the manner in which samples are taken for analysis. The actual process may be in thermodynamic equilibrium.
Polymers derived from unsaturated esters of hydronopoxyalkanols

Homopolymers of the acrylates of a series of hydronopoxyalkanols have been prepared and characterized as soft rubbery materials with some adhesive properties. The polymer from the methacrylate of hydronopoxyethanol was hard, brittle and insoluble. The crotonate of this alcohol did not homopolymerize was hard, brittle and insoluble. The crotonate of this alcohol did not homopolymerize in a free radical system. All of these esters copolymerized readily with vinyl chloride, styrene, acrylonitrile and butadiene. The vinyl chloride copolymers and styrene copolymers were rigid plastics. The butadiene copolymers were rubbery and easily crosslinked in air. The acrylonitrile copolymers were soluble in dimethylformamide. Terpolymers of these esters with butadiene and acrylonitrile were tough, rubbery compositions.
Effect of 5-aza-2′-deoxycytidine (Dacogen) on covalent histone modifications of chromatin associated with the ɛ-, γ-, and β-globin promoters in Papio anubis

Objective Treatment with the DNA demethylating drug 5-aza-2′-deoxycytidine (Dacogen; DAC) increased fetal hemoglobin and F cells to therapeutically significant levels in patients with sickle cell disease. To gain more insight into the mechanism of action of this drug and to increase our understanding of the relationship between DNA methylation and chromatin structure, we have determined the effect of DAC on covalent histone modifications of chromatin associated with the ɛ, γ-, and β-globin promoters in purified bone marrow erythroid cells of four baboons ( P. anubis ) pre- and posttreatment. Results Fetal hemoglobin increased from 6.45% ± 1.75% in pretreatment samples to 62.1% ± 7.94% following DAC. DNA methylation of three CpG sites within the ɛ-globin promoter and 5 CpG sites within the γ-globin promoter decreased more than 50% following DAC treatment. Levels of RNA polymerase II, acetyl-histone H3, acetyl-histone H4, dimethyl-histone H3 (lys4), dimethyl-histone H3 (lys36), and dimethyl-histone H3 (lys79) associated with the ɛ-, γ-, and β-globin promoters were determined by chromatin immunoprecipitation of formaldehyde-fixed chromatin followed by real-time PCR. Dacogen treatment increased the association of RNA polymerase II, acetyl-histone H3, and acetyl-histone H4 with the γ-globin promoter but did not significantly affect the association of dimethyl-histone H3 (lys4), dimethyl-histone H3 (lys36), and dimethyl-histone H3 (lys79) with the ɛ-, γ-, and β-globin gene promoters. Conclusion These experiments illustrate the usefulness of the baboon model to investigate the mechanism of pharmacologic reactivation of fetal hemoglobin synthesis at the molecular level.
Trust in E-Government Transactional Services: A Study of Citizens' Perceptions in Mexico and the U.S.

While the importance of trust in the online vendor and electronic channel for e-commerce transactions is well established, less is known about factors that influence trust in e-government services. Moreover, perceptions of trust depend heavily on the cultural context and thus can vary across countries. This study investigates differences in trust and consumption of public services by citizens across two settings: Mexico and the United States. Focus groups' results were first used to develop a survey; then a total of 455 surveys from both countries collected perceptions on four e-government services. Multi-group path analysis assessed the associations and differences between trust and service utilization. Results indicate the U.S. shows higher trust and utilization compared to Mexico. The two countries differ particularly in the impact of perceptions of the government's benevolence and competence on e-government service utilization Perceptions about the government's handling of data affects utilization only in the U.S., and the e-medium impacts utilization in both cultures. Implications for research and practice are discussed.
Correlates and Treatments of Nightmares in Adults

Nightmares, distressing dreams that primarily arise from REM sleep, are prevalent among the general population and even more so among clinical populations. The frequency of nightmares and related nightmare distress are linked to both sleep disturbance and waking psychopathology. Based on the extant evidence, nightmares appear to be particularly relevant to posttraumatic stress disorder, and may even be implicated in its pathophysiology. Significant advances in treatment have occurred in recent years, with effective pharmacological and psychosocial interventions now available. Despite the progress that has been made, however, more consistent assessment methods and more rigorous study designs are needed to fully understand the causes and consequences of nightmares.
Vitamin D supplementation during short-term caloric restriction in healthy overweight/obese older women: Effect on glycemic indices and serum osteocalcin levels

Abstract The effect of vitamin D supplementation and caloric restriction (CR) on glycemic indices and osteocalcin (OC) is not clear. In this randomized controlled double blind trial, we examined whether vitamin D3 supplementation at 2500 IU/d (D) or placebo has differential effects on markers of insulin sensitivity and bone turnover in overweight/obese postmenopausal women during 6 weeks of caloric restriction (weight loss; WL, n = 39) compared to weight maintenance (WM, n = 37). Seventy-six women (57 ± 6 years) completed this study and the WL groups lost 4 ± 1% of body weight. Baseline serum 25-hydroxyvitamin D (25OHD) was 24.8 ± 5.6 ng/mL at baseline; the rise was greatest in WL-D group (p
The Economist's Tale: A Consultant Encounters Hunger and the World Bank

Peter Griffiths London & New York, Zed Books, 2003, 249 pp., $27.50 paperback ISBN 1-84277-185-X The Economist's Tale is a partially fictionalized account of a consultant's experience working in Si...
Synthesis and Characterization of the First 2 D Neptunyl Structure Stabilized by Side‐on Cation–Cation Interactions

Sullivan et al. first introduced the concept of a cation– cation interaction (CCI) in actinide chemistry after observing unexpectedly short distances between [UO2] 2 + and [NpO2] + cations in aqueous solution.Subsequently, analogous interactions have been observed among actinyl cat ACHTUNGTRENNUNGions [AnO2] + and also between actinyl cations and transitionmetal cations. In actinide chemistry, a CCI occurs if an “yl” O atom of one actinyl ion coordinates a second actinyl ion. CCIs are most common for An cations, especially Np, although several compounds with CCIs between An actinyl ions have been reported. The CCIs between Np and U actinyl cations are important in the disproportionation of An species, because electron transfer can occur through the bridging oxo species. CCIs increase the complexity of actinide speciation in solution, and the topology and dimensionality of solid-state compounds. Species containing CCIs have been widely characterized in the solid state, in solution, and in melts by using spectroscopic techniques, such as IR/Raman, UV/Vis, large-angle X-ray scattering (LAXS), extended X-ray absorption fine structure (EXAFS), and high-energy X-ray scattering (HEXS). In the solid state, the CCI between two [AnO2] cations adopts two forms: the common T-shaped (or endon) and the rare H-shaped (or side-on) interactions. The nature of these interactions cannot be explained by simple electrostatics and is best described by noting that an actinide atom acts as a Lewis acid, whereas an oxo oxygen plays the role of a Lewis base. However, despite the large number of experimental data available, structures containing CCIs cannot be designed a priori, because understanding of the nature of these interactions remains limited. Herein, the synthesis and characterization of a new sheet structure, K ACHTUNGTRENNUNG[(NpVO2)(OH)2]·2 H2O (1), which provides a rare example of side-on CCIs, is presented (Figure 1). Spe-
Differentiation in Quinolone Resistance by Virulence Genotype in Pseudomonas aeruginosa

Pseudomonas aeruginosa is a leading pathogen that has become increasingly resistant to the fluoroquinolone antibiotics due to widespread prescribing. Adverse outcomes have been shown for patients infected with fluoroquinolone-resistant strains. The type III secretion system (TTSS) is a major virulence determinant during acute infections through the injection of effector toxins into host cells. Most strains exhibit a unique TTSS virulence genotype defined by the presence of either exoS or exoU gene encoding two of the effector toxins, ExoS and ExoU, respectively. Specific TTSS effector genotype has been shown previously to differentially impact virulence in pneumonia. In this study, we examined the relationship between TTSS effector genotype and fluoroquinolone resistance mechanisms in a collection of 270 respiratory isolates. We found that a higher proportion of exoU+ strains were fluoroquinolone-resistant compared to exoS+ strains (63% vs 49%, p = 0.03) despite its lower overall prevalence (38% exoU+ vs 56% exoS+). Results from sequencing the quinolone resistance determining regions (QRDRs) of the 4 target genes (gyrA, gyrB, parC, parE) indicated that strains containing the exoU gene were more likely to acquire ≥ 2 mutations than exoS+ strains at MICs ≤ 8 µg/ml (13% vs none) and twice as likely to have mutations in both gyrA and parC than exoS+ strains (48% vs 24% p = 0.0439). Our findings indicate that P. aeruginosa strains differentially develop resistance-conferring mutations that correlate with TTSS effector genotype and the more virulent exoU+ subpopulation. Differences in mutational processes by virulence genotype that were observed suggest co-evolution of resistance and virulence traits favoring a more virulent genotype in the quinolone-rich clinical environment.
The Strange Revival of Bicameralism

The turn of the twenty-first century witnessed a surprising reversal of the long-observed trend towards the disappearance of second chambers in unitary states, with 28 countries – all but one of them unitary – adopting the bicameral system. This article explores this development by first setting it in the context of the historical evolution of second chambers and the arguments that support bicameralism, and then exploring the characteristics that distinguish today's second chambers from first chambers. A ‘census’ of second chambers in 2014 is used to provide data on second chambers in federal and unitary states, to facilitate comparison with earlier data, and to distinguish between ‘new’ and longer-established second chambers. The article concludes that newly established second chambers are concentrated predominantly in political systems where liberal democratic principles are not established, suggesting that the debate over their role in democratic states is set to continue.
Studying “Secret Serums” — Toward Safe, Effective Ebola Treatments

The report that two seriously ill U.S. volunteers received an experimental Ebola drug has raised questions around the globe. We need to think both carefully and humanistically about balancing access to investigational agents with the need for answers about what works.
Proposal to Revise the Morphologic Criteria for the Diagnosis of Alzheimer’s Disease

Abstract Ten years have passed since the drafting of the original National Institute on Aging/American Association of Retired Persons or Khatchaturian criteria for the neuropathologic diagnosis of Alzheimer’s disease. In that time, much progress has been made in the study of this disorder. It is clear that although the Khatchaturian criteria have been useful, advances in our understanding of the morphologic substrate of the disease needs to be incorporated in any newly proposed diagnostic criteria. We propose diagnostic criteria to be employed in establishing the diagnosis of Alzheimer’s disease in a research setting. Here, we require that a level of density and distribution of senile plaques and neurofibrillary tangles be identified and that other superimposed conditions, such as major cerebral infarcts and/or Parkinson’s disease changes, are absent. We also propose separate criteria for diagnosing individuals who die in the early stages of the disease. These latter cases are of extreme research interest and are characterized by a distribution of neurofibrillary tangles that remains primarily restricted to the entorhinal cortex and hippocampus.
Passive Balancing of Rotor Systems Using Pendulum Balancers

Passive balancing techniques have received a great deal of attention in recent literature, with much of this work focused on ball balancer systems. However, for certain applications, balancing systems that use pendulums rather than rolling balls may offer distinctly improved balancing precision. This investigation seeks to provide additional insight into the performance and expected behavior of such systems. A simulation model is developed for a pendulum balancer system with isotropic supports and analyzed in detail. The influence of shaft location and friction on balancing effectiveness is considered and evaluated. In this regard, the dynamic characteristics of a pendulum balancer system are analyzed and compared to a similar ball balancer system. The conclusions and observations from the analysis and simulation studies are demonstrated and tested in a series of experimental studies.
Numerical Geometry of the Coupler Motion of a Planar 4R Closed Kinematic Chain

This paper studies the problem of analyzing the motion of the coupler link of a planar 4R closed kinematic chain from the viewpoint of constrained motion interpolation. The kinematics of the planar 4R chain is formulated using planar quaternions. The four-point interpolatory subdivision scheme for curves in the field of Computer Aided Geometric Design (CAGD) is extended to planar quaternions for the generation of an inbetween candidate position of the coupler link from a given set of four key positions. The candidate position is then checked and modified according to the kinematic constraints of the planar 4R chain. The resulting new inbetween position that satisfies the kinematic constraints is then inserted into the given set of key positions. In the early stage of this refinement process, each new inbetween position must be made to satisfy the 4R kinematic constraints exactly to ensure the correct motion. When there is sufficient number of coupler positions, one can use the unconstrained four-point interpolatory scheme to generate the inbetween positions to allow for fast animation of the coupler motion.
Reducing lifecycle energy use of network switches

The networking infrastructure is becoming a growing portion of the energy footprint in data centers as well as information technology in general. In this paper, we evaluate energy management strategies for network switches. We begin by performing a lifecycle assessment of existing switches in a data center, and find that the use phase of the lifecycle dominates. We then parametrically examine various energy management techniques to reduce this operational footprint, and find that advances in operational energy efficiency may soon increase the share of environmental burden from switch manufacturing. We conclude by discussing how these findings may influence network design in the future.
Solid landslide generated waves

Theoretical formulation describing the wave generation by a slender solid landslide is presented. The slide motion is coupled with the surface wave dynamics and both the fluid viscous (lubricative) resistance and the solid friction are considered. Numerical results are obtained for a cosine function shape slide. Numerical results show clearly the importance of the dynamic nonlinear coupling. The effects of lubricative resistance, solid friction, initial landslide speed and the slide height are discussed.
Displacements of the menisci under joint load: An in vitro study in human knees

The purpose of this study was to test whether the menisci displace under joint compression combined with internal-external torques and anterior-posterior forces at fixed flexion angles. We further determined differences in displacements between the medial and lateral menisci. Loads were applied to the joint, and joint load and displacements were measured. Meniscal displacements were measured radiographically. With a joint compressive load of 1 kN, internal and external joint rotations caused the lateral meniscus to displace, on average, 0.37 mm deg-1 in the anterior-posterior direction, while the medial meniscus displaced 0.19 mm deg-1. Anterior and posterior joint translation, performed under 1 kN joint compression, caused the lateral meniscus to displace, on average, 0.66 mm mm-1 in the anterior-posterior direction, while the medial meniscus displaced 0.43 mm mm-1. Greater meniscal displacements were found at 15 and 30 degrees flexion than at 0 degrees for the lateral meniscus in internal rotation. Lateral meniscal displacements were larger than those of the medial with posterior tibial translation at full extension and with internal rotation.
Experimental evolution of a novel pathway for glycerol dissimilation inEscherichia coli

Wild-typeEscherichia coli utilizes glycerol aerobically through an inducible pathway mediated by an ATP-dependent kinase and a glycerol 3-phosphate dehydrogenase which is a flavoprotein. A mutant, strain ECL424, employing a novel pathway for glycerol utilization was isolated. The novel pathway is mediated by an NAD-linked dehydrogenase and a dihydroxyacetone specific enzyme II of the phosphoenolpyruvate phosphotransferase system. This study describes the selection from strain ECL424, a derivative which grows more rapidly on glycerol. The derivative, strain ECL428, produces twice the parental levels of both the dehydrogenase and the enzyme II during growth on glycerol. The function of the dehydrogenase in wild-type cells is unknown, although hydroxyacetone (acetol), 3-hydroxy-2-butanone (acetoin), and 1-amino-2-propanone are gratuitous inducers. The induction can be prevented by glucose whose effect can be cancelled by external cyclic AMP. The effects of hydroxyacetone, glucose, and cyclic AMP are attenuated in the two mutants in which the dehydrogenase is produced at high basal levels. The dihydroxyacetone specific enzyme II is inducible by the substrate in both wild-type and mutant strains and serves for growth on the triose.
Multiple Interferon Stimulated Genes Synergize with the Zinc Finger Antiviral Protein to Mediate Anti-Alphavirus Activity

The zinc finger antiviral protein (ZAP) is a host factor that mediates inhibition of viruses in the Filoviridae, Retroviridae and Togaviridae families. We previously demonstrated that ZAP blocks replication of Sindbis virus (SINV), the prototype Alphavirus in the Togaviridae family at an early step prior to translation of the incoming genome and that synergy between ZAP and one or more interferon stimulated genes (ISGs) resulted in maximal inhibitory activity. The present study aimed to identify those ISGs that synergize with ZAP to mediate Alphavirus inhibition. Using a library of lentiviruses individually expressing more than 350 ISGs, we screened for inhibitory activity in interferon defective cells with or without ZAP overexpression. Confirmatory tests of the 23 ISGs demonstrating the largest infection reduction in combination with ZAP revealed that 16 were synergistic. Confirmatory tests of all potentially synergistic ISGs revealed 15 additional ISGs with a statistically significant synergistic effect in combination with ZAP. These 31 ISGs are candidates for further mechanistic studies. The number and diversity of the identified ZAP-synergistic ISGs lead us to speculate that ZAP may play an important role in priming the cell for optimal ISG function.
Processing and microstructure of

Prealloyed rapidly solidified Al-Fe-Ni alloy powder with dispersoid volume fractions of 0.19, 0.25, and 0.32 FeNiAl9 was produced by air atomization. The powder was degassed, canned, and consolidated to full density by vacuum hot pressing and extrusion or by direct extrusion. Microstructures in the alloy powder and consolidated material were characterized by means of optical, scanning (SEM), and transmission electron microscopy (TEM) and constituent phases identified by X-ray diffraction. The coarsening kinetics of the FeNiAl9 dispersoid were moni- tored by differential scanning calorimetry (DSC) and by quantitative metallography. Atomized powders exhibited two scales of microstructures: optically featureless regions and regions with a coarse dispersoid morphology. Within the featureless regions, there are three morphologies, namely, a fine uniform precipitate microstructure, a cellular microstructure, and an eutectic microstructure. The only dispersoid observed in the atomized powders and consolidated material was FeNiAl9). The two scales of microstructure were retained after consolidation, and after hot extrusion, the typical microstructure consisted of a recovered matrix structure with a grain size of 0.2 to 0.3 μm and equiaxed intermetallics of average diameter 0.1 μm. The microstructure was resistant to coarsening up to approximately 370 °C. Coarsening kinetics in this alloy system were consistent with a grain boundary diffusion model (activation energy 146 kJ/mol) and were not appreciably affected by dispersoid volume fraction.
The antigenic similarity of human low density lipoproteins.

The following human low density lipoproteins were prepared: s-lipoproteins of densities greater than 1.040 (A, B,C) a s-lipoprotein of – S 1·063 = 5 (D), a lipoprotein of – S 1·063 = 19 (E), and a lipoprotein of – S 1·063 = 70 (F). Data are presented which show the immunochemical homogeneity of the D lipoprotein rabbit-anti-D lipoprotein system. Cross-reactions between antibody to A and D lipoproteins and the above lipoproteins have been demonstrated by quantitative precipitation, quanitative complement fixation, and single and double diffusion in agar. The antigenic similarities appear to be associated with the protein portions of the molecule. The antisera produced did not differentiate the low density lipoprotein classes.
Rights, Culture, and Cosmopolitan Democracy

This essay examines the promise of universal democratization in relation to the threat of cultural homogenization. Does the promotion of human rights represent an unacceptable form of global cultural homogenization? How might it be possible to respect the dignity of individual cultures even while advancing the cause of rights as a matter of right versus wrong? The paper argues the case that these two conflicting impulses can be addressed within a discursively oriented theory of global democracy. The argument relies on Habermas's theory of communicative action, applying his discursive theory of democracy to the prospect of cosmopolitan democracy at the global level. An analysis of the Universal Declaration of Human Rights illustrates the application of discursive democracy in a cosmopolitan setting.
Developmental and seasonal changes in canary song and their relation to changes in the anatomy of song-control nuclei

Young male canaries become sexually mature in late winter, 8-12 months after hatching. During the months between hatching and sexual maturity they develop adult song. The successive stages in the development of adult song are subsong, plastic song, and stable or full song. Once stable song is achieved it lasts for the duration of the breeding season. After the end of the breeding season there is a recurrence of song instability during summer and early fall. This plastic song is followed, once more, by stable song. New song syllables are added to the song of adult male canaries and some of the earlier syllables disappear. The song repertoire sung at 2 years of age is substantially larger, and different, from that sung during the first breeding season, when the birds were 1 year old. A comparable change occurs between the second and third breeding seasons. Most of the syllables acquired by adult males are formed during the summer-fall period of song instability. Developmental and seasonal changes in song are accompanied by anatomical changes in two forebrain nuclei known to be involved in song control, the hyperstriatum ventralis, pars caudalis (HVc), and the robust nucleus of the archistriatum (RA). HVc and RA grow during the subsong and plastic song periods of song development. These nuclei reach adult size by the time stable adult song is first produced, and retain this size during the breeding season. However, the size of HVc and RA diminishes by late summer, when it becomes comparable to that of a 3- to 4-month-old bird. This reduction in size is temporary and has been corrected by the following breeding season. It is suggested that these seasonal changes in volume reflect circuit changes which are under hormonal control, and that these changes are related to processes of learning and, possibly, forgetting. Despite earlier reports of left hemispheric dominance in canary song production, we failed to find any evidence of right-left systematic differences in the size of HVc and RA during development or in adulthood. Various hypotheses relating song learning to changes in the underlying anatomy are offered.
Backgating reduction in MESFETs using an AlAs native oxide buffer layer

The authors present a new approach to the reduction of the backgating effect in GaAs MESFETs. A thin 1200 A layer of the native oxide AlxOy is used in the buffer layer directly below the conducting channel and increases the backgating threshold to –17 V, while retaining excellent device characteristics.
The cometary connection with prebiotic chemistry

Amino-acids, purines and pyrimidines may have been formed in space and brought down to Earth by comets during the final stage of the Earth's cold accretion from dust. Present-day comets seem to be the remnants of the building blocks of the early solar system, put for 4.6 billion years in “parking orbits” in the deep cold of space by the same process of orbital diffusion that brought a veneer of cometary material to the primitive Earth. The second part of the present review examines the chemical nature of comets as can be reconstructed from (so far) very incomplete evidence.
Modular Approaches to Star and Miktoarm Star Polymers by ATRP of Cross-Linkers

The topologies and site-specific functionalities of a variety of star and miktoarm star copolymers can be easily manipulated by copolymerization of monomers and cross-linkers using the ATRP technique. The polymerization of monomer prior to addition of cross-linker produced core cross-linked star polymers with initiating sites in the core, while polymerization of cross-linker before monomer led to the core cross-linked star polymers with initiating sites on the star periphery. When a mixture of linear macroinitiator and/or macromonomer was cross-linked in a one-pot reaction, miktoarm star copolymers with freely-varied arm compositions and ratios were obtained.
Effects of water vapor on the surface chemistry of calcined plutonium peroxide as determined by nitrogen adsorption

Abstract The amount of water vapor readsorbed on plutonium dioxide, following calcination of plutonium peroxide at 400°C, was measured for 14 oxide samples. It was determined that this adsorbed water decreased nitrogen adsorption and thus the specific surface area of the oxide, as determined by the BET method, was also reduced. As water was desorbed by heating, the surface area of the plutonium dioxide increased until the temperature reached 500°C. Further heating to 600°C resulted in a decrease in the surface area. The adsorption potential for nitrogen at −196°C also increased as the amount of chemisorbed water decreased. The total pore volume of the oxides was not significantly changed by the adsorbed water.
The Cholera Stigma and the Challenge of Interdisciplinary Epistemology: From Bengal to Haiti

For a century and a half cholera has been a stigmatizing disease. That the entire world was susceptible to it seemed merely to accentuate its association with Asia, and particularly with Bengal and its people. The recent epidemic in Haiti suggests that cholera still carries stigma. That stigma is the product of epistemic practices within an interdisciplinary and orientalist cholera science that took shape in the 1860s and 1870s, which have, without renewed scrutiny, prevailed largely uncontested until recent decades. Those practices involved an over-interpretation of the historical epidemiological work of John Macpherson by his colleague N. C. Macnamara. Recent research, recognizing the wide distribution and genetic instability of Vibrio cholerae, offers an alternative context for appreciating Macpherson's insights. This new program of interdisciplinary cholera research seems largely free of stigmatizing representations, but nor does it offer (or seek) a single and simple program of cholera prevention. Th...
Temporal stability of ADHD in the high-IQ population: results from the MGH Longitudinal Family Studies of ADHD.

Abstract Objective The diagnosis of attention-deficit/hyperactivity disorder (ADHD) in high-IQ youths remains controversial. Method To further explore the diagnostic validity of ADHD in this population, we studied two cohorts of high-IQ youths, both with and without ADHD, across a 4.5-year period. Results Compared to those without ADHD, high-IQ youths with ADHD had significantly higher rates of mood, anxiety, and disruptive behavior disorders at follow-up. In addition, ADHD status was a significant predictor for higher impairments across most social, academic, and family functional domains. Associations between baseline and follow-up IQ scores did not differ between groups. Syndromal persistence rates of ADHD were similar between high-IQ and average-IQ youths with ADHD. Conclusions These results provide further support for the predictive validity of ADHD in high-IQ youths. J. Am. Acad. Child Adolesc. Psychiatry , 2008; 47(7): 817–825.
Methodological issues and practical strategies in research on child maltreatment victims' abilities and experiences as witnesses.

Scientific studies of child maltreatment victims' memory abilities and court experiences have important legal, psychological, and clinical implications. However, state-of-the-art research on child witnesses is often hindered by methodological challenges. In this paper, we address specific problems investigators may encounter when attempting such research with child victims. Based on our extensive experience, we describe strategies to deal with various methodological and practical issues. Primarily, we focus on methods for: recruiting maltreatment victims, seeking consent for participation in research, ensuring representativeness of samples, interviewing children, and retaining participants longitudinally. Regarding recruitment, legal and mental health agencies have helped us attract research participants. Finding an advocate within the agency is one key to success. Regarding the process of obtaining informed consent, we describe how to ensure participant confidentiality and how to obtain consent on behalf of child maltreatment victims. We further discuss issues concerning the representativeness of maltreatment samples, a topic that is relevant to the generalizability of research findings. In child eyewitness memory studies, it is of interest to ask misleading as well as specific questions. We thus discuss issues of debriefing of child participants to prevent any possible memory taint. Finally, given the importance of studying long-term effects of child abuse and neglect, and of legal involvement, we illustrate methods for tracking maltreated participants over time and obtaining adequate retention rates in prospective longitudinal studies. We hope that the methodological advances made in previous work will help future investigators carry out child witness studies in increasingly effective and successful ways. Language: en
Hydrocortisone induction of phenylalanine hydroxylase isozymes in cultured hepatoma cells.

Abstract The hydrocortisone stimulation of phenylalanine hydroxylase activity in Reuber H4 hepatoma cells is shown to be associated with an alteration in phenylalanine hydroxylase isozyme composition. Three forms of phenylalanine hydroxylase were identified in H4 cells which have been treated with hydrocortisone; however, only one of these forms appears to be present prior to glucocorticoid treatment. The relative amounts, as well as the total amount, of the three forms and their chromatographic behavior on hydroxylapatite are nearly identical to the three phenylalanine hydroxylase isozymes found in adult rat liver. The hydroxylase isozyme composition in 2 day old rats is similar to that found in adult rats and in H4 cells treated with hydrocortisone.
Effects of competition and litter on a carnivorous plant, Drosera capillaris (Droseraceae)

Although carnivorous plants are widely recognized as being generally restricted to open habitats, tests of the effects of competition on individual performance are extremely rare. In this study, I examined the effects of the removal of herbaceous and shrub canopies on seedling density and growth, survival, and reproduction of phytometers of a small insectivorous plant, Drosera capillaris (pink sundew). I also examined the distribution of this species in relation to the occurrence of woody species in a frequently burned wet savanna in southeastern Mississippi. Killing plants and removing dead biomass increased seedling density in both open areas and shrub thickets. The removal of dead biomass following herbicide application was critical to increasing densities of seedlings. Killing plants with herbicide without also clearing residual litter and standing dead was not sufficient to increase seedling densities in shrub thickets. Although the removal of the groundcover canopy strongly influenced the density of seedlings, it had very little effect on survival, growth, and reproduction of small phytometers during a single growing season. Survival of phytometers was greater in open areas than in shrub thickets, regardless of whether the groundcover canopy was removed. Densities of both seedlings and adults were greater in open areas away from shrub thickets than beneath the woody canopies of thickets and were negatively correlated with the leaf area index of groundcover vegetation. Results of this study show that the establishment of this carnivorous plant species is limited in part by the effects of litter on seedling density in both open areas and shrub thickets.
Coordinating concurrent access in a distributed database architecture

A distributed architecture for an interactive information system is described, and a scheme for coordinating concurrent access to its data is presented. The scheme is deadlock free and is carried out without the need for centralized control. Conflicts are detected as they occur, and competing processes are given exclusive access to the data they need.
δ15N Studies of Nitrogen Use by the Red Mangrove, Rhizophora mangle L. in South Florida

To help define nitrogen (N) sources and patterns of N processing in mangrove ecosystems, mangrove leaf nitrogen contents and δ15N values were assayed in three marshes along the south Florida coast. In each marsh, leaf samples were collected from dwarf mangroves at interior locations and taller mangroves at the ocean fringe. Leaf % N and δ15N values did not differ consistently between dwarf and tall mangroves, even though there were large variations in δ15N (18‰ range, −5 to +13‰) and % N (1·2% range, 0·9–2·1%). Highest % N and δ15N values occurred along the western margin of Biscayne Bay where canals draining agricultural lands deliver high-nitrate waters to fringing mangrove marshes. High mangrove δ15N values may be good biomonitors of anthropogenic N loading to south Florida estuaries. Lower values likely reflect less anthropogenic N entering the mangrove marshes, as well as differences in plant physiology that occur along the fringe-dwarf gradient.
A time-interleaved ADC multiplexed by a blue-noise randomization method

In this paper, we propose a method to implement the randomization selection sequence in a time-interleaved (TI) ADC system. The proposed randomization sequence generator is one with blue noise spectral characteristics (high-frequency noise). This selection method guarantees that each individual channel would be selected with the lowest possible rate in order to maintain low speed requirements while still maintaining the random nature so as to effectively spread the harmonic distortions created by channel offset and gain mismatch. The blue-noise channel selection is achieved through the use of an all-digital ZA modulator. Additionally, a randomized TI ADC system employing blue-noise choppers at the input and output is proposed. This structure reduces the effects of 1/f noise and average channel offset on the TI ADC system. The proposed blue-noise randomized TI ADC with blue-noise choppers demonstrates through simulations an improvement in SFDR of up to 17 dB over traditional periodic TI ADCs and 13 dB with respect to other randomized TI ADCs
Male leopard geckos (Eublepharis macularius) can discriminate between two familiar females

Much is known about the abilities of various taxa concerning discrimination of species, sex, familiarity-based discrimination and individual discrimination. However, literature pertaining to the precision of discrimination within lizard taxa assumes that discrimination between familiar and unfamiliar individuals can be extrapolated to include individual discrimination between two familiar individuals. The present study had two aims. First, we determined that male leopard geckos (Eublepharis macularius) can concurrently become familiar with two different females and discriminate those females from a novel female. Second, we investigated the ability of male leopard geckos to distinguish between two familiar females using a habituation-dishabituation paradigm. Males habituated to the presence of the first female, exhibited by decreased typical courtship behaviours directed towards that female. Male courtship behaviours, however, were reinstated upon introduction of the second familiar female. These results indicate that males possess the ability to discriminate between two familiar females and adjust their courtship efforts appropriately.
Using the KL-center for efficient and accurate retrieval of distributions arising from texture images

Image retrieval is a common problem in many computer vision applications and the literature abounds with techniques with impressive retrieval accuracies. Several of these techniques use probability distributions to represent the "objects" they intend to retrieve. We present a novel approach to search such collections of distributions efficiently. Like many standard data structures, our method uses an "average" to represent a large set (Le., cluster) of objects, thus allowing the search to disregard an unpromising subset with only one comparison to its average. Our contribution lies in choosing the average: Inspired by information theory, we choose a representative that is optimally "close" in a minimax sense to all members of its set when measured using the Kullback-Liebler (KL) divergence. We present a texture retrieval system and test it on the CUReT database, measuring accuracy and efficiency. We find that using the KL-center yields speed ups of more than a factor of three over an exhaustive search while guaranteeing identical accuracy. The KL-center also out-performs other commonly used representatives such as the arithmetic mean. Although we present results only in texture retrieval, our approach will likely aid image and shape retrieval as well.
Winter Feeding Success of Stream Trout under Different Streamflow and Turbidity Conditions

Abstract To investigate the relationship between turbidity and trout feeding success in natural systems, we sampled the stomach contents of resident rainbow trout Oncorhynchus mykiss and coastal cutthroat trout O. clarkii clarkii under different streamflow and turbidity conditions during winter in two northwestern California streams (total sample size = 161). Feeding success generally did not differ sharply for fish collected under low versus high streamflow and turbidity conditions. Bioenergetics modeling suggested that feeding success on average did not reach maintenance levels for seven of eight sets of samples, but extensive feeding on oligochaetes during one period of elevated streamflow resulted in positive energy balances. Occasional peaks in food intake could greatly influence the energy budgets and growth of trout in mild-winter systems. Under some natural conditions, trout appear able to achieve relatively high feeding success when turbidity limits visibility.
Predicting species responses to climate change: demography and climate microrefugia in California valley oak (Quercus lobata)

Anticipating species movement under climate change is a major focus in conservation. Bioclimate models are one of the few predictive tools for adaptation planning, but are limited in accounting for (i) climatic tolerances in preadult life stages that are potentially more vulnerable to warming; and (ii) local-scale movement and use of climatic refugia as an alternative or complement to large-scale changes in distribution. To assess whether these shortfalls can be addressed with field demographic data, we used California valley oak (Quercus lobata Nee), a long-lived species with juvenile life stages known to be sensitive to climate. We hypothesized that the valley oak bioclimate model, based on adults, would overpredict the species’ ability to remain in the projected persisting area, due to higher climate vulnerability of young life stages; and underpredict the potential for the species to remain in the projected contracting area in local-scale refugia. We assessed the bioclimate model projections against actual demographic patterns in natural populations. We found that saplings were more constricted around surface water than adults in the projected contracting area. We also found that the climate envelope for saplings is narrower than that for adults. Saplings disappeared at a summer maximum temperature 3 °C below that associated with adults. Our findings indicate that rather than a complete shift northward and upward, as predicted by the species bioclimate model, valley oaks are more likely to experience constriction around water bodies, and eventual disappearance from areas exceeding a threshold of maximum temperature. Ours is the first study we know of to examine the importance of discrete life stage climate sensitivities in determining bioclimate modeling inputs, and to identify current climate change-related constriction of a species around microrefugia. Our findings illustrate that targeted biological fieldwork can be central to understanding climate change-related movement for long-lived, sessile species.
Is Physical Layer Error Correction Sufficient for Video Multicast over IEEE 802.11g Networks

Wireless video multicast enables delivery of popular events to many mobile users in a bandwidth efficient manner. However, providing good and stable video quality to a large number of users with varying channel conditions remains elusive. A promising solution to this problem is the use of packet level Forward Error Correction (FEC) mechanisms. However, the adjustment of the FEC rate is not a trivial issue due to the dynamic wireless environment. This decision becomes more complicated if we consider the multi-rate capability of the existing wireless LAN technology that adjusts the transmission rates based on the channel conditions and the coverage range. In this paper, we explore the dynamics of Forward Error Correction (FEC) schemes in multi-rate wireless local area networks. We study the fundamental behavior of a 802.11g network which already has embedded error correction in physical layer, under unicast and broadcast modes in a real outdoor environment. We then explore the effectiveness of packet level FEC over wireless networks with multi-rate capability. In order to evaluate the system quantitatively, we implemented a prototype using open source drivers, and ran experiments. Based on the experimental results, we provide guidelines on how to efficiently use FEC for wireless multicast services in order to improve the overall system performance. We argue that even there is a physical layer error correction, using a higher transmission rate together with stronger FEC is more efficient than using a lower transmission rate with weaker FEC for multicast.
Roads versus Schooling: Growth Effects of Government Choices

This paper studies the growth effects of productive public expenditures on education and public capital in an endogenous growth model of overlapping generations. The model is calibrated to Latin American data, and the effects of raising government expenditures on education and public capital are computed. Results show that increases in these public expenditures have moderate, positive effects on per capita growth and income under different scenarios. In addition, re-allocating expenditures from public capital to education while keeping the budget constant can raise growth up to a threshold.