cssi/SciSciGPT-SciSciNet huggingface dataset:
The Chromodomain Protein MRG-1 Facilitates SC-Independent Homologous Pairing during Meiosis in Caenorhabditis elegans

Summary Homologous chromosome pairing is a prerequisite to establish physical linkage between homologs, which is critical for faithful chromosome segregation during meiosis I. The establishment of pairing is genetically separable from subsequent synapsis, defined as stabilization of pairing by the synaptonemal complex (SC). The underlying mechanism of presynaptic pairing is poorly understood. In the nematode Caenorhabditis elegans , a unique cis -acting element, the pairing center (PC), is essential for presynaptic pairing; however, it is not known whether and how the remainder of the chromosome contributes to presynaptic pairing. Here we report direct evidence for presynaptic pairing activity intrinsic to non-PC regions, which is facilitated by a conserved chromodomain protein, MRG-1. In mrg-1 loss-of-function mutants, pairing is compromised specifically in non-PC regions, leading to nonhomologous SC assembly. Our data support a model in which presynaptic alignment in non-PC regions collaborates with initial PC pairing to ensure correct homologous synapsis.
A practical microcylinder appearance model for cloth rendering

This article introduces a practical shading model for cloth that can simulate both anisotropic highlights as well as the complex color shifts seen in cloth made of different colored threads. Our model is based on extensive Bidirectional Reflectance Distribution Function (BRDF) measurements of several cloth samples. We have also measured the scattering profile of several different individual cloth threads. Based on these measurements, we derived an empirical shading model capable of predicting the light scattering profile of a variety of threads. From individual threads, we synthesized a woven cloth model, which provides an intuitive description of the layout of the constituent threads as well as their tangent directions. Our model is physically plausible, accounting for shadowing and masking by the threads. We validate our model by comparing predicted and measured light scattering values and show how it can reproduce the appearance of many cloth and thread types, including silk, velvet, linen, and polyester. The model is robust, easy to use, and can simulate the appearance of complex highlights and color shifts that cannot be fully handled by existing models.
The effect of diazoxide on coronary blood flow

Abstract Hemodynamic measurements were made on anesthetized and unanesthetized dogs to observe the effects of injection of diazoxide. The measurements included the electrocardiogram, blood pressures, cardiac output and coronary blood flow. Calculated values included coronary and total peripheral resistance, left ventricular work and efficiency. Coronary flow increased markedly and with larger doses the increase persisted for three to four hours. Calculated coronary arteriolar resistance decreased more in response to the diazoxide than did total peripheral resistance. Direct intracoronary injection of diazoxide in the conscious dog showed that the primary cardiac effect of this drug is to dilate the coronary arteriole.
UV and sunlight driven photoligation of quantum dots: understanding the photochemical transformation of the ligands.

We have recently reported that photoinduced ligation of ZnS-overcoated quantum dots (QDs) offers a promising strategy to promote the phase transfer of these materials to polar and aqueous media using multidentate lipoic acid (LA)-modified ligands. In this study we investigate the importance of the underlying parameters that control this process, in particular, whether or not photoexcited QDs play a direct role in the photoinduced ligation. We find that irradiation of the ligand alone prior to mixing with hydrophobic QDs is sufficient to promote ligand exchange. Furthermore, photoligation onto QDs can also be carried out simply by using sunlight. Combining the use of Ellman’s test with matrix-assisted laser desorption/ionization and electrospray ionization mass spectrometry, we probe the nature of the photochemical transformation of the ligands. We find that irradiation (using either a UV photoreactor or sunlight) alters the nature of the disulfide groups in the lipoic acid, yielding a different product mi...
Stimulus generalization and transfer of training in rabbits conditioned to electrical stimulation of lateral geniculate nucleus

Abstract Rabbits were classically conditioned by pairing electrical stimulation of the dorsal lateral geniculate nucleus (LGN) with peripheral electric shock as the unconditioned stimulus. In Experiment 1 generalization and transfer of training between contralateral LGN were examined. In Experiment 2 frequency generalization gradients were examined with total stimulus energy (TSE) either varied or kept constant. The chief findings of Experiment 1 were that (a) reliable eyeblink and heart rate conditioning were observed, and (b) transfer of training, but not stimulus generalization occurred between LGN. This transfer was specifically due to the previous conditioning. In Experiment 2 response frequency of unconditioned eye openings to LGN stimulation varied as a function of stimulus frequency. In contrast, the highest response frequency for conditioned eyelid closings during generalization testing occurred at the stimulus frequency used during training provided that TSE was kept constant; some generalization occurred to higher and lower stimulus frequencies. When frequency was varied without keeping TSE constant, the highest response rates occurred at stimulus frequencies higher than the training stimulus.
Using undergraduate teaching assistants in a small college environment

The use of undergraduate teaching assistants in computer science courses is not new but is primarily thought of as a way to help with large classes in universities and rarely for small classes in small colleges. In this paper we discuss the success we have had over the past 2 years using undergraduate students as teaching assistants for a number of small computer science classes. Our experience has shown that having undergraduates as teaching assistants helps to engage students with the material, creates a more relaxed classroom environment in which students feel more free to ask questions, improves the effectiveness of class time, and improves class quality. We believe that our experiences using undergraduate teaching assistants can be beneficial not only to small colleges but also to large universities.
Self-Calibrating Embedded RF Down-Conversion Mixers

This paper proposes a self-calibrating approach for embedded RF down-conversion mixers. In the proposed approach, the output of the RF mixer is analyzed by using on-chip resources for testing and the mixer performs self-compensation for parametric defects using tuning knobs. The tuning knobs enable the RF mixer to self-calibrate for multi-parameter variations induced due to process variability. Using this methodology, it is demonstrated that performance compensation of RF down-conversion mixers can be performed simultaneously for critical specifications such as Gain and 1-dB compression point (P1dB).
Wildland fire emissions, carbon, and climate: Seeing the forest and the trees – A cross-scale assessment of wildfire and carbon dynamics in fire-prone, forested ecosystems

Wildfires are an important component of the terrestrial carbon cycle and one of the main pathways for movement of carbon from the land surface to the atmosphere. Fires have received much attention in recent years as potential catalysts for shifting landscapes from carbon sinks to carbon sources. Unless structural or functional ecosystem shifts occur, net carbon balance in fire-adapted systems at steady state is zero when assessed over the entire post-fire successional sequence and at landscape scales. When evaluated at fine spatial scales and over short periods of time, however, wildfires may seem to release more carbon to the atmosphere than remains on site. Measurements of wildfire carbon emissions are thus highly biased by the spatial and temporal scales that bound them, and may over- or under-estimate carbon source-sink dynamics that provide critical feedbacks to the climate system. This synthesis paper provides a description of the ecological drivers of wildfires and carbon in forested ecosystems across the spatial and temporal scales at which system drivers (e.g., climate, weather), behaviors (e.g., wildfire occurrence, spread, intensity), and resulting patterns (e.g., vegetation composition and structure, carbon emissions) occur and interact. Improved understanding of these relationships is critical if we are to anticipate and respond to major changes in the global earth system expected in the coming decades and centuries.
Functions of health fatalism: fatalistic talk as face saving, uncertainty management, stress relief and sense making

Much research on fatalism assumes that fatalistic statements represent a global outlook that conflicts with belief in the efficacy of health behaviours. Other scholars have suggested a more contextual approach, suggesting that fatalism fulfils personal and social functions. This study analyses 96 in-depth lay interviews in the US, most with low-income members of the general public, about four diseases: heart disease, lung cancer, diabetes and depression. Within these interviews, fatalistic statements always occurred alongside statements endorsing the utility of behaviours for protecting health. This usage pattern suggests that these statements may have useful functions, rather than being simply a repudiation of the utility of health choices. We examine four functions that are suggested by previous researchers or by the participants' comments: stress relief, uncertainty management, sense making and (less strongly) face saving. As these themes indicate, individuals often make fatalistic statements to express an understanding of locally or broadly limiting factors for health efficacy, including genes, spiritual agents, prior behaviours, personality, and other factors.
Evolution of the R2 Retrotransposon Ribozyme and Its Self-Cleavage Site

R2 is a non-long terminal repeat retrotransposon that inserts site-specifically in the tandem 28S rRNA genes of many animals. Previously, R2 RNA from various species of Drosophila was shown to self-cleave from the 28S rRNA/R2 co-transcript by a hepatitis D virus (HDV)-like ribozyme encoded at its 5' end. RNA cleavage was at the precise 5' junction of the element with the 28S gene. Here we report that RNAs encompassing the 5' ends of R2 elements from throughout its species range fold into HDV-like ribozymes. In vitro assays of RNA self-cleavage conducted in many R2 lineages confirmed activity. For many R2s, RNA self-cleavage was not at the 5' end of the element but at 28S rRNA sequences up to 36 nucleotides upstream of the junction. The location of cleavage correlated well with the types of endogenous R2 5' junctions from different species. R2 5' junctions were uniform for most R2s in which RNA cleavage was upstream in the rRNA sequences. The 28S sequences remaining on the first DNA strand synthesized during retrotransposition are postulated to anneal to the target site and uniformly prime second strand DNA synthesis. In species where RNA cleavage occurred at the R2 5' end, the 5' junctions were variable. This junction variation is postulated to result from the priming of second strand DNA synthesis by chance microhomologies between the target site and the first DNA strand. Finally, features of R2 ribozyme evolution, especially changes in cleavage site and convergence on the same active site sequences, are discussed.
Orthogonal stimulus variation and attention in dimensional contrast

These experiments examined one way in which the allocation of attentional resources can change performance during a visual discrimination task. Pigeons were trained to discriminate visual forms under conditions that produced dimensional contrast. In three experiments, negative training stimuli differed from positive stimuli either along a primary physical dimension alone or along both a primary dimension and an orthogonal dimension. When a negative stimulus differed from positive stimuli along two dimensions, discrimination of that negative stimulus improved. For one type of visual form, discrimination of the positive stimuli declined with orthogonal variation in a negative stimulus, whereas for other visual forms, there was no decline in performance. These results are consistent with a model of dimensional contrast that suggests that differences in the allocation of attentional resources determine discrimination performance. The results also indicate that the organization of stimulus dimensions plays a crucial role in the allocation of attentional resources in these settings.
An overview of BLOOM

BLOOM is a system for doing software understanding through visualization. It provides facilities for static and dynamic data collection. It offers a wide range of data anal?yses. It includes a visual query language for specifying what information should be visualized. All these are used in con?junction with a back end that supports a variety of 2D and 3D visualization strategies.
Process parallels in related groups

The theoretical basis for the repetition of themes in related groups is addressed by describing similar processes in four systems: inpatient psychiatric ward, inpatient psychotherapy group, supervisory group, and group psychotherapy division. The principles of general system theory help explain process parallels in allied groups and illuminate group process.
Electromagnetic fields in the nuclear source region

The source region of a nuclear detonation is the region of space in which electric currents induced by the radiation output of the weapon are present. Outside this region, which typically has a radius of up to a few kilometers, the electromagnetic field created by these currents propagates essentially in a free-space environment. Interest in the source-region environment produced by a surface or near-surface detonation has been strong in the nuclear-weapons community for many years, principally because of the necessity of hardening missile silos and, more recently, the horizontal shelters of the MX system against the electromagnetic effects of a nearby burst. The fact that the nuclear source-region environment is as complicated as it is presents an extremely large set of problems and challenges to the electromagnetic theorist and the numerical analyst. In the remainder of this article the author discusses the nuclear source-region environment itself, electromagnetic interactions in the source region, the capabilities and limitations of some of our present computer codes, and areas in which further work will be useful. The hope is to make the readers of this article aware of some of the problems which are currently faced bythose responsible for studying the electromagnetic effects of nuclear weapons, and perhaps to excite their interest in this most challenging area of electromagnetics.
Molecular dynamics simulation of nanostructural organization in ionic liquid/water mixtures.

Molecular dynamics simulations have been carried out to investigate nanostructural organization in mixtures of 1-octyl-3-methylimidazolium nitrate ionic liquid and water at multiple water concentrations. Evolution of the polar network, water network, and micelle structures is visualized and analyzed via partial radial distribution functions. The calculated static partial structure factors show that within the range of water contents examined, polar networks, water networks, and micelles possess an approximately invariant characteristic length at around 20 A. Furthermore, the above calculations point out that, as the amount of water increases, the polar network is continuously broken up (screened) by the intruding water, while the structural organization of the water network and the micelle exhibits a turnover. At the turnover point, the most ordered micelle (cation−cation) structure and water (water−anion−water) network are formed. Thereafter, the structural organization abates drastically, and only loose...
An evaluation of seasat SAR imagery for urban analysis

Digitally processed Seasat SAR imagery of the Denver, Colorado, area is analyzed with regard to the types of urban data that can be detected and/or inferred from satellite-borne L-band systems. Black-and-white images of the scene were generated at three scales to determine the advantages and detail discernible at each level of display. The large-scale imagery was density-sliced to evaluate the feasibility of producing a semiautomated land-cover classification from the SAR data. Gray level classes were assigned colors to aid interpretation and subsequently compared with the black-and-white images to assess the contribution of each technique and benefits of combining the data from both procedures.
Deficient interleukin‐10 production by neonatal T cells does not explain their ineffectiveness at promoting neonatal B cell differentiation

Neonatal T cells are poor promoters of Ig secretion by neonatal B cells. Since IL-10 has been shown to play a role in B cell differentiation, we investigated the relationship of IL-10 production by neonatal T cells and their ability to provide B cell help. Neonatal CD4+(CD8-) T cells and adult naive CD4+ (CD8-/CD45RO-) T cells activated with immobilized anti-CD3 produced consistently less IL-10 than adult memory CD4+(CD8-/CD45RA-) T cells. Production of IL-10 by adult and neonatal T cells was dependent on IL-2, but was unaffected by supplemental IL-4. Despite diminished IL-10 production, supplemental IL-10 increased neonatal T cell-dependent Ig secretion only modestly, but did not increase Ig heavy chain isotype switching. This contrasted with the ability of IL-10 to enhance the secretion of all Ig isotypes by adult B cells stimulated in the presence of either IL-2 or IL-4. These results suggest that IL-10 can promote T cell-dependent Ig secretion but not Ig heavy chain isotype switching by neonatal B cells. However, deficient IL-10 production alone does not account for the poor ability of neonatal T cells to support neonatal B cell Ig production.
Exploiting an elastic 2-tiered cloud architecture for rich mobile applications

This dissertation exploits 2-Tier cloud architecture for rich mobile applications. It is based on the observation that using local resources in close proximity to the user, i.e. local clouds or cloudlets (in the second tier), can increase the quality and performance of mobile applications. In contrast, public cloud offerings (in the first tier) offer scalability at the cost of higher delays, higher power consumption and higher price on the mobile device. We introduce new concept of Space-Time workflow as the modeling framework for mobile applications. Based on this framework we try to define the optimal mobile applications (considering power, price and delay as the Qos). This problem in general is NP-Hard. By considering a class of heuristics called CRAM we try to achieve near optimal solution. We will show the efficiency of our developed techniques through simulation and prototyping of different classes of rich mobile applications such as signal processing and streaming applications.
Incorporating prior knowledge in environmental sampling: ranked set sampling and other double sampling procedures

Environmental sampling can be difficult and expensive to carry out. Those taking the samples would like to integrate their knowledge of the system of study or their judgment about the system into the sample selection process to decrease the number of necessary samples. However, mere convenience or non-random sampling can severely limit statistical inference. Methods do exist that integrate prior knowledge into a random sampling procedure that allows for valid statistical inference. Double sampling methods use this extra information to select samples for measurement, thus reducing the number of necessary samples (in order to achieve a desired objective) and thereby reducing sampling costs. The level of prior information required can range from a linear relationship with a known auxiliary variable to simple ranking based on auxiliary information. We examine three types of double sampling methods (ranked set sampling, weighted double sampling and double sampling with ratio estimation), with accompanying examples from Oregon stream habitat data. All three methods can provide increased precision and/or lower sampling costs over simple random sampling. The appropriate double sampling method for the data and research situation depends upon the type of prior information available. The categories of prior information are summarized in a table and illustrated using the example data.
Field theory of the two-dimensional ising model: II. Nonlocal specific heat

The nonlocal specific heat is calculated for the two-dimensional Ising model and found to be identical to that found by Bray for the four-dimensional model. Furthermore, it is noted that analytic continuation in terms of a spectral function provides an especially simple description of the nonlocal specific heat. From unitarity the spectral function is the rate of pair production in the Minkowski metric, and is calculated to be equal to the velocity of the outgoing particles.
Modeling and Analysis of Fixel Designs for Micromanufacturing Active Fixturing

This paper presents an investigation of fixel design alternatives for active (dynamic) fixturing to be incorporated into mesoscale manufacturing systems. Using simple compliant mechanisms and components, fixels exhibiting mechanically adjustable stiffness characteristics are achievable. Via manual or automated stiffness adjustments, these fixels provide functionality for enabling greater control of the dynamic response of the workpiece subject to vibrations and/or variations in contact forces at the tool-workpiece-mixture interface. To quantify the fixel functionality, this paper presents theoretical models of the stiffness characteristics expressed as a function of the mechanical variable(s), thus forming a basis for exploring the adjustability in stiffness achievable for each fixel design. Also presented are results of the dynamic behavior of the active fixturing implemented in a milling process based on a "regenerative force, dynamic deflection model" augmented with the active fixturing variable stiffness model and inclusion of tool runout. These simulation results indicate the expected performance of the active fixturing upon its implementation in actual fixturing for the creation of micron features on micro- and macroparts.
Community-based multiple-gate screening of children at risk for conduct disorder

The present study employed a multiple-gate screening procedure to identify children at risk for the development of conduct disorder. Measures of cross-setting disruptive behavior and parent discipline practices were administered in sequential fashion to screen a population of 7,231 children attending suburban elementary schools. Convergent validity of the respective gating measures was confirmed by significant correlations with adjustment constructs. Analyses of covariance performed between positive screens, negative screens, and low-risk comparison children on adjustment constructs at each gate supported the discriminative validity of the gating procedure. Hierarchical regression analyses demonstrated that the gating measures were predictive of diagnostic ratings of attention deficit hyperactivity disorder and oppositional defiant disorder that were obtained 18 months following the screening. A stepwise logistic regression analysis indicated that the best predictors of high-risk group membership were variables related to family process, including poor family communication and involvement, poor maternal coping skills, and an external parent locus of control.
ACCOUNTABILITY AND CREDIBILITY IN THE MANAGEMENT OF COMPLEX HAZARDOUS TECHNOLOGY

The requirements for dependable management of complex hazardous technologies include multiple barriers against serious failure, clear accountability for errors, and credibility for the decision-making process. Unfortunately, these requirements are in direct conflict. These conflicts can undermine the public's assurance that their health and safety concerns are being properly addressed. These conflicts can be reduced by the adoption of policies that enhance information exchange and evaluation, thereby, complementing the current policies based on physical safeguards and adversarial processes. 13 references, 3 figures.
In Vitro Formation of Resting Spores by the Insect Pathogenic Fungus Entomophaga maimaiga

Abstract Field-collected resting spores (azygospores) of the fungal pathogen of Lymantria dispar (gypsy moth), Entomophaga maimaiga, have been used to release this biological control agent in areas where this pathogen is not established. We have found that E. maimaiga can produce resting spores in vitro using Grace’s insect tissue culture medium (95%) plus fetal bovine serum (5%). The majority of spores become mature between 7 and 21 days after cultures are initiated. Spore production varies by fungal isolate; of 38 isolates tested, 10 produced no resting spores while 7 produced >1000 resting spores/ml. Resting spore production was not affected when isolates were mixed. Glycerol (used for fungal storage), trehalose, and selected amino acids each inhibited resting spore formation. Fetal bovine serum was required for spore production but the presence of >5% yielded lower resting spore densities. A large surface area:volume ratio (12.5 cm 2 :ml versus 4.2 cm 2 :ml) was required for abundant formation of resting spores. At present, resting spores have only been produced in small volumes with a maximum of 3 × 10 4 resting spores/ml.
Anisotropic diffusion in a finite cylinder, with geochemical applications

Atomic diffusion in minerals may not be well represented by solutions to the diffusion equation for a sphere with a singlevalued diffusivity, either because they have platy or elongated habits or because the energetics of diffusion is sensitive to crystallographic direction. In many cases, a cylinder having characteristic radial and axial diffusivities is arguably a better model, but rigorous solutions to the anisotropic diffusion equation for a finite cylinder have not been available. Here we develop general analytical solutions that capture both the internal distribution of diffusant as a function of time, C(r, z, t), and the fraction, F, of diffusant lost during a specified thermal history. These solutions are shown to conform with existing analytical expressions for limiting cases of diffusion in a slab or infinite cylinder. We present, in addition, a simple numerical (finite difference) approach that not only reproduces the results of our analytical expressions but also enables us to move beyond some of the limitations of the equations to simulate complex natural scenarios involving non-zero and time-dependent boundary conditions, arbitrary initial distribution of diffusant within the cylinder and simultaneous diffusion and radiogenic ingrowth. The complementary nature of the two approaches is emphasized and several illustrative applications to ‘real-world’ problems are described, including noble-gas thermochronometry and halogen–hydroxyl interdiffusion in apatite.
Task-oriented design of concentric tube robots using mechanics-based models

We introduce a method for task-oriented design of concentric tube robots, which are tentacle-like robots with the potential to enable new minimally invasive surgical procedures. Our objective is to create a robot design on a patient-specific and surgery-specific basis to enable the robot to reach multiple clinically relevant sites while avoiding anatomical obstacles. Our method uses a mechanically accurate model of concentric tube robot kinematics that considers a robot's time-varying shape throughout the performance of a task. Our method combines a search over a robot's design space with sampling-based motion planning over its configuration space to compute a design under which the robot can feasibly perform a specified task without damaging surrounding tissues. To accelerate the algorithm, we leverage design coherence, the observation that collision-free configuration spaces of robots of similar designs are similar. If a solution exists, our method is guaranteed, as time is allowed to increase, to find a design and corresponding feasible motion plan. We provide examples illustrating the importance of using mechanically accurate models during design and motion planning and demonstrating our method's effectiveness in a medically motivated simulated scenario involving navigation through the lung.
Natural Occurrence and Laboratory Studies of the Fire Ant Pathogen Vairimorpha invictae (Microsporida: Burenellidae) in Argentina

We surveyed 154 sites in north-central Argentina and sampled 2,528 fire ant colonies for the presence and intracolonial prevalence of the microsporidium, Vairimorpha invictae Jouvenaz & Ellis, in the red imported fire ant, Solenopsis invicta Buren. The concentrations of meiospores and binucleate spores were quantified in workers and sexuals; and the occurrence and intracolonial prevalence of dual infections with Thelohania solenopsae Knell, Allen & Hazard were studied. To study the effect of V. invictae in infected colonies of S. invicta, we compared the proportion of infected living workers to the proportion of infected dead workers, and compared the survival of uninfected and infected workers. V. invictae occurred at 13% of the sites and 2.3% of the colonies. At times, the disease reached epizootic levels in certain areas. We found vegetative stages in 4.8-52.3% of eggs, larvae, pupae, and queens, meiospores in 4-56.3% of pupae and mature stages, and binucleate spores in 9.5-63% of all life stages, except eggs. Evidence for transovarial transmission is provided. The percentage of sexual males infected was significantly higher than that of sexual females (44.9 versus 15.9%, respectively). Dual infections (V. invictae + T. solenopsae) occurred in 0.24% of the colonies. V. invictae was present in 9.3% of living workers and in 56.7% of dead workers. Mortality rates of workers from Vairimorpha-infected colonies were higher than those of workers from uninfected colonies. Survival times of infected workers were 18.8-31.7% less than those of uninfected workers. The studies reported here contribute to the evaluation of V. invictae for use as a classical biological control agent against the red imported fire ant in the United States.
The exchange of C14 glucose across the membrane of the human erythrocyte.

We have measured the equilibrium efflux of C14 labeled glucose across the cell membrane of the human erythrocyte under conditions when glucose was present in equal concentrations on both sides of the cell membrane, and also the net efflux of C14 labeled glucose from glucose-loaded cells into a large extracellular environment that contained no glucose. A method of ultrafiltration through millipore filter discs was developed to obtain samples of medium during the loss of cell isotope to a medium free of isotope. Fluxes with half times as low as five seconds could be determined accurately and reproducibly. With this method we have extended the observations of other workers down to glucose concentrations of 0.03 M and found as others had previously that the half time for tracer exchange would decrease with a decrease in the equilibrium glucose concentrations. Further, by measuring equilibrium fluxes and maximal net fluxes of cells from the same blood sample, we have obtained evidence that the carrier laden with glucose is transported more rapidly than the free carrier.
Laser photolysis of 2,6-dinitrotoluene in solution

Abstract Transient species produced following 266 nm photolysis of 2,6-DNT have been attributed to the aci-quinoid isomer (pH 2.0, polar). The aci-species is produced through rapid intramolecular hydrogen transfer. In methanol, it undergoes deprotonation with a rate of ≈ 5 × 104 s−1 to yield an equilibrium [anion]:[aci] ratio of ≈ 1.1. The enhancement of this rate in methanol:water mixtures is interpreted in terms of dielectric constant.
Carrier screening of electric field and electroabsorption saturation in InGaAs-GaAs quantum well structure

Saturation of the electroabsorption is obtained in the quantum confined Stark effect (QCSE) at low optical intensities and low electric fields, in a strained InGaAs-GaAs quantum well modulator structure operating at the exciton energy. This effect is attributed to carrier-induced screening of the internal electric field, and its implications for devices using the QCSE are discussed.
Late Wisconsin macrofossil records of desert vegetation in the American Southwest

Until recently, the oldest-known packrat (Neotoma spp.) midden records of desert scrub vegetation were less than 10,500 yr old and were restricted to altitudes below 300 m in the northern Sonoran Desert. Recent discovery of macrofossil assemblages in the Mojave Desert extends the record of desert vegetation back to 14,800 yr ago and to altitudes as high as 910 m. Although xerophytic conifer woodland was widespread in current desert habitats during the Late Wisconsin and early Holocene, the development of extensive desert vegetation was not delayed until the beginning of the middle Holocene. A regional vegetation mosaic of desert scrub and woodland existed at altitudes below 1000 m in the Mojave Desert during the last part of the Late Wisconsin.
The changing role of science in our society

I am especially pleased to be your speaker tonight, for I have long admired this organization and its ways of doing things. For nearly thirty years I have watched the American Geophysical Union prosper under wise leadership as the organization has met the changing challenges and opportunities of the times. When I first arrived in Washington in 1939 I worked under the directorship of John A. Fleming, one of the Union's great presidents. I have known personally most of the Union's presidents since that time. I had the special privilege of working with Ewing, Berkner, and Malone during my tenure as co-editor of the Journal of Geophysical Research. More recently, the Union has continued to enjoy top leadership under Woollard and Ackermann, with a fine successor, Helmut Landsberg, named to carry on.
Database resources of the National Center for Biotechnology

In addition to maintaining the GenBank(R) nucleic acid sequence database, the National Center for Biotechnology Information (NCBI) provides data analysis and retrieval resources for the data in GenBank and other biological data made available through NCBI's Web site. NCBI resources include Entrez, PubMed, PubMed Central (PMC), LocusLink, the NCBITaxonomy Browser, BLAST, BLAST Link (BLink), Electronic PCR (e-PCR), Open Reading Frame (ORF) Finder, References Sequence (RefSeq), UniGene, HomoloGene, ProtEST, Database of Single Nucleotide Polymorphisms (dbSNP), Human/Mouse Homology Map, Cancer Chromosome Aberration Project (CCAP), Entrez Genomes and related tools, the Map Viewer, Model Maker (MM), Evidence Viewer (EV), Clusters of Orthologous Groups (COGs) database, Retroviral Genotyping Tools, SAGEmap, Gene Expression Omnibus (GEO), Online Mendelian Inheritance in Man (OMIM), the Molecular Modeling Database (MMDB), the Conserved Domain Database (CDD), and the Conserved Domain Architecture Retrieval Tool (CDART). Augmenting many of the Web applications are custom implementations of the BLAST program optimized to search specialized data sets. All of the resources can be accessed through the NCBI home page at: http://www.ncbi.nlm.nih.gov.
Risk-Constrained Coordination of Cascaded Hydro Units With Variable Wind Power Generation

This paper presents a stochastic hourly coordination strategy for wind units and cascaded hydro generation as storage to firm up the hourly dispatch in a generating company (GENCO). The proposed strategy is based on the stochastic price-based unit commitment (Stochastic PBUC) formulation which includes wind energy imbalance charges. The forecast errors of electricity market price and wind speed are simulated with the Monte Carlo method via a scenario approach. The risk-aversion constraints are considered for limiting a GENCO's financial risks when considering uncertain wind power generation. The proposed optimization model is solved by mixed-integer linear programming (MIP) and illustrative examples examine the effectiveness of the proposed risk-based coordination model for optimizing a GENCO's payoff.
Photoperiod alters affective responses in collared lemmings

This study examined photoperiodic regulation of affective behaviours in collared lemmings (Dicrostonyx groenlandicus). Male and female lemmings were housed in either long (LD 22:2), intermediate (LD 16:8), or short days (LD 8:16) for 9 weeks. Exposure to short days induced moult to a winter pelage and gonadal regression in male, but not female, lemmings. Lemmings housed in long days reduced anxiety-like responses in the elevated plus maze. Depressive-like behaviours were decreased in the intermediate photoperiod relative to other photoperiod groups.
Predictors of life satisfaction among caregivers of individuals with multiple sclerosis

Research on life satisfaction among caregivers of persons with multiple sclerosis (MS) is sparse. This study examined the extent to which MS-specific disease and psychosocial characteristics predict caregiver life satisfaction. Participants were 64 caregivers of patients with MS and the patients for whom they care. Multiple regression analysis indicated that caregiver perception of illness uncertainty and patients’ unawareness of deficits have unique value in predicting caregiver life satisfaction, even after accounting for general financial status. Gender and level of social support were also important contributing factors to caregiver life satisfaction. The findings suggest that duration and severity of the patients’ illness take a greater toll on life satisfaction of caregivers with low versus high social support, particularly among women caregivers.
The process trellis: a software architecture for intelligent monitors

The process trellis software architecture aids the programmer in building intelligent monitors for hierarchical domains by providing a way to guarantee real-time performance, structuring the interactions between modules, guiding the decomposition of the computation, and providing a well-defined interface with the external world. There is a natural parallel execution strategy for these decision processes which enables programs that would otherwise be unable to meet their real-time constraints to do so and permits speedup of programs without real-time constraints. One way to demonstrate a software architecture's utility is by an existence proof; HEARSAY-II is such a proof for blackboard architectures. While still a research project, a process trellis shell, which implements most of the features of the process trellis software architecture, is being used for an intelligent cardiovascular monitor that is intended for eventual use in a cardiac intensive care unit. >
Efficient infection of brain microvascular endothelial cells by an in vivo-selected neuroinvasive SIVmac variant

A neuroinvasive/neuropathogenic SIV variant termed SIVmac182 was previously isolated and characterized (Watry et al, 1994). This neuroinvasive strain was derived from the uncloned strain SIVmac251 through serial animal passage of infected microglia, unlike previously reported neurovirulent strains. Importantly, the virus described here was isolated from a strain which already demonstrates limited neuroinvasiveness in vivo, through a route of inoculation which exerts selective pressure for variants in the periphery that can naturally cross the blood-brain barrier and gain access to the brain. Examination of animal tissues indicated that the neuroinvasive strain was capable of replicating in brain microvascular endothelial cells (BMEC). Therefore, we developed an in vitro model of BMEC infection in which to examine mechanisms of virus neuroinvasiveness and neuropathogenicity as well as to address mechanisms of HIV-induced dementia. Results obtained with this in vitro system indicate that growth in BMEC may predict neuroinvasiveness in vivo, and furthermore, that brain passage of virus results in the generation of neuroinvasive strains which demonstrate an increased efficiency of BMEC infection in vitro.
Metal-mirror-based resonant-cavity enhanced light-emitting diodes by the use of a tunnel diode contact

We, for the first time, designed and fabricated resonant-cavity light-emitting diodes for high-speed optical communications using a tunnel diode contact scheme. Use of a tunnel diode provides extra freedom in designing the device contact and cavity mirror, which allows the realization of a resonant cavity without requiring distributed Bragg reflectors. The fabricated resonant-cavity light-emitting diodes have half the spectrum bandwidth and nearly triple the fiber-coupled power of noncavity devices.
Increased Vascular Endothelial Growth Factor Levels in the Vitreous of Eyes With Proliferative Diabetic Retinopathy

The vitreous levels of the angiogenic polypeptide vascular endothelial growth factor (also known as vascular permeability factor) were measured and compared in eyes with and without proliferative diabetic retinopathy. Undiluted vitreous samples from 20 eyes were collected at the time of vitrectomy, and vascular endothelial growth factor levels were determined by using a time-resolved immunofluorometric assay. Vitreous vascular endothelial growth factor levels were significantly higher in eyes with proliferative diabetic retinopathy than in eyes without proliferative diabetic retinopathy (P = .006; Wilcoxon Rank Sum Test). The median vitreous concentration in the eyes with proliferative diabetic retinopathy was 29.1 pM and exceeded the known concentration required for the maximal proliferation of vascular endothelial cells in vitro. These data are consistent with vascular endothelial growth factor serving as a physiologically relevant angiogenic factor in proliferative diabetic retinopathy.
Tailoring the Electrochemical Behavior of Multiwalled Carbon Nanotubes Through Argon and Hydrogen Ion Irradiation

As carbon nanotubes CNTs inevitably contain defects, it is of interest to investigate the possibility of artificially introducing defects to tune their properties. This is especially important for applications in electrochemistry and field emission. We report on the electrochemical behavior, through cyclic voltammetry measurements, of multiwalled CNT samples with different defect densities induced through exposure to hydrogen and argon irradiation. Ar exposure leads to CNT charging and reversible/quasireversible electron-transfer kinetics, while hydrogen irradiation yields irreversible kinetics. Correlation with Raman spectroscopy implies the termination of residual dangling bonds in CNTs by hydrogen, causing an elimination of reactive sites.
Visualization-based discovery and analysis of genomic aberrations in microarray data

Chromosomal copy number changes (aneuploidies) play a key role in cancer progression and molecular evolution. These copy number changes can be studied using microarray-based comparative genomic hybridization (array CGH) or gene expression microarrays. However, accurate identification of amplified or deleted regions requires a combination of visual and computational analysis of these microarray data. We have developed ChARMView, a visualization and analysis system for guided discovery of chromosomal abnormalities from microarray data. Our system facilitates manual or automated discovery of aneuploidies through dynamic visualization and integrated statistical analysis. ChARMView can be used with array CGH and gene expression microarray data, and multiple experiments can be viewed and analyzed simultaneously. ChARMView is an effective and accurate visualization and analysis system for recognizing even small aneuploidies or subtle expression biases, identifying recurring aberrations in sets of experiments, and pinpointing functionally relevant copy number changes. ChARMView is freely available under the GNU GPL at http://function.princeton.edu/ChARMView .
Immunohistochemistry and electron microscopy in Langerhans cell histiocytosis confined to the skin

Four cases of benign Langerhans cell histiocytosis limited to the skin were studied. In all three self-healing cases (cases 2, 3, and 4) many dense bodies, myelin bodies, and worm bodies were found. In one chronic case (case 1) none of these was identified. In all four cases, in addition to CD1, HLA-DR, and S-100 stains, interferon-γ and S-100 β-subunit were positive in the dermal tumor cells. Both interferon-γ and S-100 β-subunits were negative in the normal epidermal Langerhans cells. A comprehensive literature review yielded 87 cases of skin-limited Langerhans cell histiocytosis. These cases could be subgrouped into three categories: (1) those that resolved spontaneously, (2) those that responded to therapy and had no recurrence, and (3) those with persistent or recurrent lesions, not responding to therapy but still limited to the skin.
Synthesizing speech from Doppler signals

It has long been considered a desirable goal to be able to construct an intelligible speech signal merely by observing the talker in the act of speaking. Past methods at performing this have been based on camera-based observations of the talker's face, combined with statistical methods that infer the speech signal from the facial motion captured by the camera. Other methods have included synthesis of speech from measurements taken by electro-myelo graphs and other devices that are tethered to the talker - an undesirable setup. In this paper we present a new device for synthesizing speech from characterizations of facial motion associated with speech - a Doppler sonar. Facial movement is characterized through Doppler frequency shifts in a tone that is incident on the talker's face. These frequency shifts are used to infer the underlying speech signal. The setup is farfield and untethered, with the sonar acting from the distance of a regular desktop microphone. Preliminary experimental evaluations show that the mechanism is very promising - we are able to synthesize reasonable speech signals, comparable to those obtained from tethered devices such as EMGs.
Tourists' Satisfaction Judgments: An Investigation of Emotion, Equity, and Attribution

This study investigates the relationships between aspects of consumption behavior— emotion, equity, and attribution—and the consequences of tourists' satisfaction. It also examines their different ...
From world hunger to food sovereignty: food ethics and human development

The role of Amartya Sen's early work on famine notwithstanding, food security is generally seen as but one capability among many for scholars writing in development ethics. The early literature on the ethics of hunger is summarized to show how Sen's Poverty and Famines was written in response to debates of past decades, and a brief discussion of food security as a capability follows. However, Sen's characterization of smallholder food security also supports the development of agency in both a political and an economic sense. Economic agency is discussed and tied to longstanding literatures on the moral significance of farming within political economy. Finally, while the newly emergent literature on food sovereignty includes many themes, it is shown to be re-articulating arguments that stress smallholder's economic agency as a development goal. This pattern of argument thus provides a way to reconcile at least some of the claims being advanced under the banner of food sovereignty with the human development...