cssi/SciSciGPT-SciSciNet huggingface dataset:
Management of echinococcal cysts of the liver.

In the United States, hepatic echinococcosis is being encoun­ tered more frequently now than in the past because of the immigration of afflicted persons from countries in which the disease is endemic. Nevertheless, any single medical center would seldom encounter enough patients to have a meaning­ ful cumulative experience for analysis. In this issue ofMayo Clinic Proceedings (pages 1193 to 1197), Behrns and van Heerden present a detailed analysis of the 23 patients with this unusual condition treated during a 55-year period at the Mayo Clinic. Their analysis leads them to conclude that "conservative" surgical treatment is less effective in prevent­ ing recurrence of hydatid disease than is a "radical" surgical procedure. Our experience at UCLA Medical Center with 24 patients who had 46 hepatic hydatid cysts treated during a 25-year period 1 is in close agreement with the symptom complexes, laboratory evaluation, and distribution of cysts described by the Mayo authors. We could not categorically conclude, however, that radical surgical therapy was the best manage­ ment for all cysts. Recognizing that more extensive opera­ tions on the liver are associated with greater morbidity and mortality than are less extensive operations, we reported the following conclusions: series of patients resulted in no deaths and only two recur­ rences that necessitated reoperation (8%). In the current report, Behrns and van Heerden correctly point out that use of mebendazole alone is ineffective treat­ ment for hepatic echinococcosis. In another study, this agent also offered no benefit for killing of parasites or preventing recurrent disease when administered for 1 or 2 months pre­ operatively in comparison with a group of patients who received no mebendazole preoperatively.' Whether a role exists for postoperative adjuvant therapy with meben­ dazole-or the newer scolicide, albendazolet-i-in the pre­ vention of recurrent hydatid disease cannot be determined until appropriate trials have been conducted.
Capillary electrochromatography using a fluoropolymer as the chromatographic support material.

Fused-silica capillary columns were packed with ethylene chlorotrifluoroethylene (ECTFE) particles for use in capillary electrochromatography (CEC). Electroosmotic flow (EOF) was generated in these columns using acetonitrile-water mixtures as the mobile phase. Electroosmotic mobilities of 1.6 x 10(-4) cm2 V(-1) s(-1) (linear velocities of 1 mm s(-1)) were observed using a mobile phase without an electrolyte present. The EOF in the ECTFE-packed columns is enhanced when using trifluoroacetic acid (TFA) as a mobile phase additive; electroosmotic mobilities of 3.65 x 10(-4) cm2 (V-1) s(-1) (linear velocity of 2.5 mm s(-1)) were observed. This enhancement of EOF is attributed to dynamic coating of the ECTFE particles by TFA. Other electrolytes (i.e., Tris/Tris-HCl buffer and H3PO4) in the mobile phase did not have such an enhancement of EOF. However, a slight enhancement of EOF is observed, for example, if small quantities of TFA are added to the mobile phase containing Tris buffer. The potential of ECTFE for CEC is demonstrated by separating a mixture of amino acids.
Molecular investigations on the dilemma of nitrogen‐fixing characteristics of Azotomonas

The ability of Azotomonas to reduce atmospheric nitrogen has been an issue of controversy since this genus was included in the family Azotobacteraceae. Here we report the investigations on the nitrogen fixation characteristics of Azotomonas fluorescens strain ATCC13544 and show that it can grow in both liquid medium and on solid agar plates made with modified BURK nitrogen-free medium supplemented with ammonium acetate as a nitrogen source. In contrast, when ammonium acetate was omitted from this medium, the cells did not show any noticeable growth. Southern blotting analysis of the chromosome of Azotomonas strain ATCC13544 did not show any hybridization with a probe made of DNA sequences corresponding to the nifH gene of Azotobacter vinelandii. Based on these results, we conclude that the Azotomonas fluorescens ATCC13544 does not contain the conventional genetic information on its chromosome that is needed to utilize atmospheric nitrogen as the sole source nitrogen to support its growth.
Hidden Source Behavior Change Tracking and Detection

An important task of modeling complex social behaviors is to observe and understand individual/group beliefs and attitudes. These beliefs, however, are not stable and may change multiple times as people gain additional information/perceptions from various external sources, which in turn, may affect their subsequent behavior. To detect and track such influential sources is challenging, as they are often invisible to the public due to a variety of reasons -- private communications, what one randomly reads or hears, and implicit social hierarchies, to name a few. Existing approaches usually focus on detecting distribution variations in behavioral data, but overlook the underlying reason for the variation. In this paper, we present a novel approach that models the belief change over time caused by hidden sources, taking into consideration the evolution of their impact patterns. Specifically, a finite fusion model is defined to encode the latent parameters that characterize the distribution of the hidden sources and their impact weights. We compare our work with two general mixture models, namely Gaussian Mixture Model and Mixture Bayesian Network. Experiments on both synthetic data and a real-world scenario show that our approach is effective on detecting and tracking hidden sources and outperforms existing methods.
Foreign Direct Investment in the United States: An Analysis by Country of Origin

Given the large size and rapid growth of foreign direct investment in the United States, this subject is a central concern of U.S. firms and U.S. government policymakers. This study explores the factors that contribute to the explanation of FDI in the United States by country of origin of investment. Evidence from the past twelve years shows that the main significant positive influences are home country's exports to the United States and home country market size. Significant negative influences include the home country's imports from the United States, the cultural and geographic distances of the home country from the United States, and the exchange rate (fx/$).
The Power of Groups for Older Adults: A Comparative Study of European American and Latino Senior Mutual Aid Groups

ABSTRACT This paper presents the findings of a qualitative study of members of two groups for senior adults. One of the groups consisted of members from the Latino community and the other was composed of European Americans. Although members of these groups differed, they valued the mutual aid and support received in the weekly groups. Recommendations are that group workers expand and inspire social group work for seniors and be sensitive to ethnic/cultural variables when leading groups.
Elevated serum levels of 1α, 25-dihydroxycholecalciferol in lactating rats

LACTATION represents a challenge to regulation of calcium metabolism. Because of the high rate of calcium transfer to the milk, the lactating rat consuming a commercial stock diet maintains a reduced serum Ca level1. The increased need for Ca seems to be met primarily by increased intestinal absorption of Ca (ref. 1). Since vitamin D is important for regulation of Ca metabolism, particularly during lactation2, and since the circulating level of the active metabolite lα,25-dihydroxyvitamin D3 (1α,25-(OH)2D3) seems to be regulated according to Ca needs3, we determined by radioreceptor binding assay the serum levels of 1α,25-(OH)2D3 in vitamin D-fed lactating rats. We report here that these levels are two- to fourfold higher than those of non-lactating controls. Rats deprived of vitamin D during lactation fail to show elevated metabolite blood levels and develop marked hypocalcaemia, thus indicating the importance of the elevated blood level of 1α,25-(OH)2D3 for Ca metabolism during lactation.
Anatomical Observations on Floating Leaves

Abstract An examination of 24 genera of aquatic plants having floating leaves and leaf-like thalli has been made. Functional stomata occur on the adaxial sides of floating leaves of angiosperms and some ferns, and in some floating leaves there are stomata on the abaxial surface as well. Most floating leaves have prominently chambered mesophyll, and in some instances the chambers are locally enlarged and form buoys.
Synthesis and antiprotozoal activity of cationic 2-phenylbenzofurans.

A series of cationically substituted 2-phenylbenzofurans 1−49 have been synthesized, and their in vitro antiprotozoal properties against Trypanosoma brucei rhodesiense, Plasmodium falciparum, and Leishmania donovani, as well as cytotoxicity against mammalian cells, have been evaluated. Eight dications exhibited antitrypanosomal activities comparable to that of pentamidine and melarsoprol. Twenty-six compounds were more active than pentamidine, and seven dications demonstrated increased activities against P. falciparum than artemisinin. Five congeners were more active against L. donovani than pentamidine. Introduction of methoxy or hydroxy groups in the 7- and/or 2′-position afforded derivatives that were highly selective against T. b. rhodesiense, P. falciparum, and L. donovani. Fourteen 2-phenylbenzofurans displayed excellent in vivo efficacies in the acute mouse model of trypanosomiasis, curing 3/4 or 4/4 animals at 4 × 5 mg/kg. Diamidine 1 and di(N-isopropyl)amidine 45, administered at 4 × 1 mg/kg, exh...
Fatigue crack propagation in crystalline polymers: effect of moisture in nylon 66

As part of a study of the effects of crystallinity on fatigue crack propagation (FCP) behaviour in crystalline polymers, the FCP response of nylon 66 was examined as a function of both stress intensity factor range (ΔK) and water content. It was found that FCP rates were exponential functions of ΔK, as expected. However, the FCP rates at constant ΔK decreased as the water content was increased to about 3%; at saturation (8% water), the FCP rates were higher than that observed in dry specimens. Results were interpreted in terms of the incorporation of tightly bound water up to a maximum of one water molecule per two amide groups (at∼ 2% water), followed by the incorporation of loosely bound water (at saturation). The tightly bound water evidently toughens the polymer, while the loosely bound water has a predominantly weakening effect. Examination of fracture surfaces revealed a transition from terminal unstable crack growth (at water contents up to 3%) to tearing (at saturation). Classical fatigue striations were observed only in the specimens containing 2% water—the first time such striations have been unequivocally identified for any crystalline polymer.
Response of tumor‐bearing rats to high‐fat total parenteral nutrition

Total parenteral nutrition (TPN) solutions fed to tumor-bearing rats have been shown to affect host and tumor metabolism. This study was initiated to evaluate the effect of two intravenous nutrient regimens on carcass and organ composition as well as tumor composition and growth. Thirty Sprague-Dawley rats were implanted with Walker 256 carcinosarcoma and randomly assigned to one of three diet groups: (1) A, a glucose-based TPN formula; (2) B, a lipid-based TPN formula, isocaloric to A; and (3) C, a purified powdered diet fed ad libitum. Equal assignments were made for non-tumor-bearing controls. Tumor-bearing rats infused with diet B had the highest amount of carcass and organ fat as well as the lowest carcass and organ protein. Tumor composition paralleled carcass composition, but tumor weight and density did not differ among dietary groups. Tumor weight to body weight ratios were highest in the group fed diet B. These data indicate that although tumor growth remains unchanged, alterations in body and tumor composition are effected by a high fat TPN solution.
Electrochemistry of sulfide flotation: Growth characteristics of surface coatings and their properties, with special reference to chalcopyrite and pyrite

Abstract Characteristics of surface coatings which form when sulfide minerals react with aqueous solutions in the absence and presence of flotation reagents are discussed. The coatings form by electrochemical and chemical reactions, and dissolution, adsorption, surface reaction and precipitation processes. Of special interest to flotation is the proposed formation of a metal-deficient layer adjacent to the unreacted sulfide mineral and a precipitated layer of metal-hydroxide, oxide, sulfate, etc., adjacent to the solution phase. If the metal-oxide layer does not adhere to the metal-deficient layer collectorless flotation occurs, otherwise not. The characteristics of gangue minerals play a special role in detachment of the oxide under certain conditions. Since both kinetic and thermodynamic factors are involved, an interaction of hydrodynamic and chemical variables occurs. Selected results are discussed, particularly for the chalcopyrite/solution interface.
Mixing Business With Politics: A Meta-Analysis of the Antecedents and Outcomes of Corporate Political Activity

Corporate political activity (CPA) has increased rapidly in the United States; however, research findings are spread across several social science fields. The authors use meta-analysis to aggregate findings involving two sets of research questions: (1) what factors and to what extent do these factors influence firms to engage in CPA, and (2) does CPA, in turn, affect firm performance and, if so, to what extent? Two important contributions are made. First, the evidence suggests that, although many factors shape CPA, very few affect CPA to a large extent. Second, the results suggest that CPA is positively related to firm performance and is an important determinant of firm performance. The authors build on this evidence to suggest several future research directions.
Time‐course of inorganic nitrogen uptake and incorporation by natural populations of freshwater phytoplankton

SUMMARY. 1. Time-course measurements of NH4+ and NO3−uptake were made on the natural phytoplankton populations in a eutrophic lake at a time when these nutrients were at their lowest annual concentration. 2. Both NH4+ and NO3− uptake was increased at least five-fold during the first 5 min of incubation following near saturating pulses of these nutrients. 3. Elevated uptake was also observed following low level (∼2μg N 1−1) pulses of NH4+ and NO3−, but substrate depletion during the first hour of incubation may have been partially responsible for this apparent enhancement. 4. Incorporation of I5N into TCA-insoluble material (protein) following the saturating NH4+ pulse was increased less than total cellular 15N uptake, whereas no elevation of 15N incorporation into protein was observed following a saturating NO3−pulse. 5. The percentage of I5N incorporated into protein, with respect to total cellular uptake, was ∼32% and ∼12% for NH4+ and NO3−, respectively, following 5 h of incubation.
Transfer effects of an observation stimulus as a function of its relevancy

Three groups of Ss, 20 each, learned three successive concept identification (CI) tasks, on which one group had no observation stimulus (So), a second group had a relevant So, and a third group had an irrelevant So. Each type of So continued to affect CI learning as a function of its relevancy. Predictions of relative improved performance on later tasks by the irrelevant So group, based on a rational operator model, did not occur.
Nonlinear internal waves in the South China Sea: Observation of the conversion of depression internal waves to elevation internal waves

[1] The conversion of depression nonlinear internal solitons to elevation internal waves has been observed twice at the South China Sea continental shelf break. Shipboard X-band radar, tow-yo CTD, ADCP and high frequency acoustic flow visualization of the process are presented. The data focuses on up slope propagation of depression internal solitons from a water depth of ∼264 m to a water depth of ∼110 m. Dissipation by large amplitude shear instabilities was observed. The kinetic energy density was found to be a decreasing monotonic function of range with an energy dissipation rate coefficient of 0.063 km−1. The rate of energy dissipation over the ∼16.5 km soliton propagation path was 0.17 W/m/m. Simple numerical models of the waveform evolution are qualitatively compared to the observations. The observations, extracted scale parameters and dissipation rates should be useful for testing a variety of evolution equation representations of internal soliton propagation.
Spontaneous coherence and the quantum Hall Effect in triple-layer electron systems

We investigate spontaneous interlayer phase coherence and the occurrence of the quantum Hall effect in triple-layer electron systems. Our work is based on a simple tight-binding model that greatly facilitates calculations and whose accuracy is verified by comparison with recent experiments. By calculating the ground state in an unrestricted Hartree-Fock approximation and the collective-mode spectrum in a time-dependent Hartree-Fock approximation, we construct a phase diagram delimiting regions in the parameter space of the model where the integer quantum Hall effect occurs in the absence of interlayer tunneling.
A model for analyzing the external effects of new towns on regional development

Abstract Title VII of the New Communities and Urban Growth Act of 1970 enables the Department of Housing and Urban Development to guarantee bonds used to finance New Town development by the private sector. Large scale New Town development may drastically affect regional land use patterns. New Towns may siphon resources away from central cities, reducing their tax base, increasing their ghettos and accelerate urban decay. The model proposed in this paper is designed to analyze the effect of subsidized New Towns on a region's growth. The output of the model would enable the policy makers to expand their decision horizon in evaluating bond guarantee applications. The model is composed of four integrated submodels; a national dynamic input-output model, an interregional forecasting model, a Lowry type land use model and a financial evaluation model.
Stochastic optimization based economic dispatch and interruptible load management with distributional forecast of wind farm generation

We study stochastic optimization of economic dispatch (ED) and interruptible load management using short-term distributional forecast of wind farm generation. Specifically, we develop a Markov-chain-based distributional forecast model for wind farm generation based on spatial and temporal characteristics of the wind turbine power output in a wind farm. Built on the distributional forecast model, the joint optimization of ED and interruptible load management is cast as a stochastic optimization problem. The proposed stochastic ED problem is compared with the deterministic ED problem using the persistence wind generation forecast model, and also with the scenario-based ED formulation which uses all possible wind generation states. Numerical studies, using a modified IEEE RTS 24-bus system and realistic wind measurement data from an actual wind farm, demonstrate the significant benefits obtained by leveraging the Markov-chain-based distributional forecast and the interruptible load management.
Representational properties common to phonological and orthographic output systems

Abstract Linguistic and psycholinguistic research over the last decade has provided a wide array of evidence indicating that the mental representations of spoken word forms are highly structured objects. One prominent aspect of the enriched notion of phonological structure is that the representation of segmental length (quantity) is separate from that of segmental identity; and another is that segmental sequences are organized into prosodic constituents. This paper discusses data from acquired dysgraphia which suggest that certain attributes of phonological forms also hold of orthographic forms as well — including the skeletal representation of quantity and the grouping of segments into syllabic constituents. E.g., the geminate letters ee and tt in orthographic forms like career and butter are represented and processed as single graphemic objects that are associated with two CV units on a tier that encodes quantity. It is argued that such properties of phonological and orthographic form reflect general conditions imposed on lexical representation, and not modality-specific representational constraints.
With Eyes to the Future: A Brief History of Cognitive Development.

Research patterns from the past three decades and several current directions of research are used to describe emerging trends in the study of cognitive development. These trends are discussed as moving the field into new areas, particularly biology, learning, and social context, and contributing to a more integrated understanding of psychological development.
The prevalence of migraine in Meniere's disease

This study attempted to determine the prevalence of migraine in unilateral classic Meniere's disease and vestibular Meniere's disease. Diagnostic criteria for these three entities were identified and charts of patients with episodic vertigo were reviewed. A questionnaire was designed to assess the prevalence of migraine using criteria established previously by other authors. Questionnaires were mailed to patients with classic Meniere's disease, patients with vestibular Meniere's disease, and a normal control group. The response rates from the questionnaires in the three groups were 75%, 70%, and 36%. The percentages of the respondents who met the predetermined criteria for migraine in the three groups were 22%, 81%, and 33%. The significant difference in migraine prevalence between classic and vestibular Meniere's disease suggests the possibility of different etiologies for the two entities.
Ecosystem Properties of Urban Land Covers at the Aboveground–Belowground Interface

Understanding of ecological differences among urban land covers can guide the sustainable management of urbanized landscapes for conservation of ecosystem services. The objective of our study was to compare ecosystem properties at the aboveground–belowground interface of three landcover types commonly found in residential landscapes: lawns, bark mulch, and gravel mulch. Using unmowed vegetation as a reference land cover, we measured surface soil variables (to 5 cm depth), CO2 fluxes, and ground temperatures in experimental field plots within 3 years after their creation. Each land cover had a distinctive set of ecosystem properties. Mulched plots had significantly warmer soil and surface temperatures, wetter soils and faster surface litter decomposition than vegetated plots. Variables associated with soil C and earthworm numbers were consistently lowest in gravel-covered soils, whereas bark mulch plots had highest earthworm abundances, lowest soil bulk density, and temporally variable soil organic matter dynamics. Compared to unmowed plots, lawns had higher soil carbon, CO2 fluxes, and temperatures but lower earthworm abundances especially during 2005 drought conditions. We conclude that ecosystem properties of the land covers were influenced by the composition, density, and arrangement of materials comprising their aboveground habitat structures. We discuss our results within an ecosystem services framework and suggest that interpretations of our findings depend on in situ urban environmental contexts and landscape management objectives. Future studies of urban land covers, their ecosystem properties and associated ecosystem services are needed to help provide a scientific basis for sustainable urban landscape management.
MECHANISMS OF ENHANCED TRANSMEMBRANE SIGNALING BY AN INSULIN RECEPTOR LACKING A CYTOPLASMIC BETA -SUBUNIT DOMAIN

Abstract We have recently characterized a mutant insulin receptor (HIRΔ978) in which the insulin receptor β-subunit was truncated at amino acid residue 978. Compared with parental Rat1 cells, the cells expressing the truncated receptor exhibited enhanced sensitivity to insulin's biologic actions. All of these effects are now extended to transcriptional events, since we now show enhanced sensitivity to insulin stimulation of c -fos mRNA expression. These effects were insulin-specific, since insulin-like growth factor-1 stimulation of glucose incorporation into glycogen, α-aminoisobutyric acid uptake, and thymidine incorporation into DNA were normal. In addition, the truncated receptor exhibited enhanced sensitivity only in vivo, but not in vitro, since the kinase activity of wheat germ agglutinin-purified receptor preparations was comparable between HIRΔ978 and parental Rat1 insulin receptors. Parental rat endogenous insulin-like growth factor-1 receptors and transfected human insulin receptors form hybrid receptors as well as homologous tetrameric receptors. The normal heterotetrameric receptors possess kinase activity in vivo leading to tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1) and its association with the p85 regulatory subunit of phosphatidyl inositol 3-kinase. Interestingly, preincubation with human-specific anti-insulin receptor antibody abolished the increased insulin sensitivity in glucose incorporation into glycogen in HIRΔ978 cells. Furthermore, microinjection of anti-IRS-1 antibody into HIRΔ978 cells inhibited insulin stimulation of DNA synthesis. In summary: 1) truncated receptors on the cell surface confer enhanced insulin sensitivity in vivo; 2) the normal heterotetrameric receptors are functionally active and couple to IRS-1 efficiently; and 3) IRS-1 is an important molecule transmitting insulin's biological signals in HIRΔ978 cells.
Frequency of Thrombophilia-Related Genetic Variations in Patients with Idiopathic Pulmonary Embolism in an Urban Emergency Department

Background: The frequency of the thrombophilic genetic variants factor V Leiden (FVL) G1691A, prothrombin G20210A, and methylenetetrahydrofolate reductase ( MTHFR ) C677T in acutely symptomatic ambulatory patients with idiopathic pulmonary embolism (PE) has not been measured. Methods: This prospective case–control study included patients presenting to urban emergency departments (EDs) with chest pain or shortness of breath. Cases were classified as idiopathic PE (49 patients with PE, but without overt risk factors for thrombosis). Control groups included ( a ) patients with nonidiopathic PE (152 patients with PE and risk factors); ( b ) patients in whom PE was excluded (91 patients who had PE ruled out with a structured protocol, including follow-up); and ( c ) patients in whom PE was not suspected (193 patients without a workup for PE, who were free of PE on follow-up). Blood DNA extracts were analyzed by PCR and restriction fragment length polymorphism analysis for the FVL, prothrombin, and MTHFR sequence variations. Results: Either the FVL or prothrombin variant was found in 10% (95% confidence interval, 3%–22%) of patients with idiopathic PE compared with 13% (8%–20%) of nonidiopathic PE, 2% (5%–14%) of PE excluded, and 9% (5%–14%) of PE not suspected patients. Patients with idiopathic PE tended to have a higher frequency of homozygous MTHFR sequence variants, but mean (SD) plasma homocysteine concentrations were not increased [15.6 (5.4) μmol/L vs 12.8 (4.6) μmol/L for homozygous, and wild-type, respectively; P = 0.40]. Conclusions: The frequency of either the FVL or prothrombin sequence variant was not increased in idiopathic PE patients compared with nonidiopathic PE patients or patients who had PE excluded. These data suggest that genotyping to detect idiopathic PE would have limited clinical utility in the urban ED setting.
Work In Progress: Use of Interdisciplinary Teams in Game Development Classes

The development of computer games is labor-intensive. Modern game development requires the effort of a team of skilled professionals to integrate multimedia content with complex software. Producing high-quality software game products requires large teams to rely on high levels of communication, organization, and planning to avoid costly delays and failures. The author created a two-semester sequence of courses focusing on the application of software engineering principles in the design and implementation of computer games. ABET accreditation guidelines require students to participate on interdisciplinary teams to solve engineering problems. Students in the author's advanced game design course work with game animation art students from a neighboring art college. This paper summarizes the content of this course and the author's experience in teaching this course during its first offering using interdisciplinary teams. Student evaluations of this interdisciplinary team course offering indicate high levels of satisfaction.
Untemplated Oligoadenylation Promotes Degradation of RISC-Cleaved Transcripts

Double-stranded RNA, processed to small interfering RNAs (siRNAs) by Dicer and incorporated into the RNA-induced silencing complex (RISC), triggers gene silencing by a variety of pathways in eukaryotes. RNA interference involving the degradation of homologous transcripts is the best-characterized mechanism. However, the fate of the RNA fragments resulting from siRNA-directed cleavage is poorly understood. We have identified a gene (MUT68) in the unicellular green alga Chlamydomonas reinhardtii that is required for the efficient decay of siRNA-targeted transcripts. MUT68 encodes a noncanonical polyadenylate polymerase that adds untemplated adenines to the 5' RNA fragments after siRNA-mediated cleavage and appears to stimulate their exosome-dependent degradation.
Virulence of clinical and environmental isolates of Burkholderia oklahomensis and Burkholderia thailandensis in hamsters and mice

Burkholderia pseudomallei is the etiologic agent of the tropical disease melioidosis and is considered to be a potential biological weapon. Two B. pseudomallei-like species, Burkholderia oklahomensis and Burkholderia thailandensis, have been described in the literature. Infections with both of these microorganisms have occurred in the United States, but little is known about the relative virulence of these isolates in animal models of infection. In this study, B. oklahomensis and B. thailandensis CDC2721121 were determined to be avirulent in hamsters and mice at all challenge doses examined. The virulence of B. thailandensis CDC3015869, on the other hand, was more similar to the virulence of isolates of B. thailandensis from Southeast Asia.
Contrasting the Efficacy of Selection on the X and Autosomes in Drosophila

To investigate the relative efficacy of both positive and purifying natural selection on the X chromosome and the autosomes in Drosophila, we compared rates and patterns of molecular evolution between these chromosome sets using the newly available alignments of orthologous genes from 12 species. Parameters that may influence the relative X versus autosomal substitution rates include the relative effective population sizes, the male and female germline mutation rates, the distribution of allelic effects on fitness, and the degree of dominance of novel mutations. Our analysis reveals that codon usage bias is consistently greater for X-linked genes, suggesting that purifying selection consistently has greater efficacy on the X chromosome than on the autosomes across the Drosophila phylogeny. However, our results are less consistent with respect to the efficacy of positive selection, with only some lineages showing a higher substitution rate on the X chromosome. This suggests that either the distribution of selective effects of mutations or other relevant parameters are sufficiently variable across species to tip the balance in different ways in individual lineages. These data suggest that rates of substitution are not solely governed by adaptive evolution. This genome-wide analysis provides a clear picture that the efficacy of selection varies intragenomically and that this effect is markedly more consistent across the phylogeny in the case of purifying selection. Our results also suggest that simple models that predict systematic differences in rates of evolution between the X and the autosomes can only be made to be compatible with these Drosophila data if the relevant population genetic parameters that drive substitution rates differ among species and chromosomal contexts.
Parallel and Distributed Simulation Systems

Originating from basic research conducted in the 1970's and 1980's, the parallel and distributed simulation field has matured over the last few decades. Today, operational systems have been fielded for applications such as military training, analysis of communication networks, and air traffic control systems, to mention a few. The article gives an overview of technologies to distribute the execution of simulation programs over multiple computer systems. Particular emphasis is placed on synchronization (also called time management) algorithms as well as data distribution techniques.
ENERGY USE, COST, AND PRODUCT QUALITY IN PRESERVING VEGETABLES AT HOME BY CANNING, FREEZING, AND DEHYDRATION

Carrots, zucchini, and summer squash were processed by canning, freezing, and dehydration according to procedures used in the home. Energy used was measured and the cost of preservation was calculated with the packaging and amortized equipment cost included. Reduced ascorbic acid and carotene contents were determined within a week after processing and after 6 months of storage. Sensory quality of the processed vegetables was evaluated in less than a month after processing. The vegetables were cooked with salt added for sensory evaluation. Freezing required the shortest processing time and resulted in products with the highest sensory quality, with ratings well above minimum acceptability, and the most ascorbic acid (assuming the canned liquor is not used) and carotene. More energy (electricity) was required to process and store vegetables by freezing than by canning or dehydrating with a commercially available electric dehydrator; however, the overall cost for freezing preservation was estimated to be as low as or lower than the cost for the other two preservation methods if the freezer could be kept full. With the freezer only half-full freezing would cost more than canning or dehydration for a long term (> 6 months) storage. Canning used much less electric energy and was slightly cheaper in overall preservation cost than dehydrating with the electric dehydrator, and the canned products retained much more ascorbic acid and carotene than the dehydrated products. Nearly all ascorbic acid was lost during dehydration. The canned and dehydrated products were rated low in sensory quality, with ratings mostly below minimum acceptability.
Investigation of the performance of GAFT, a novel network anomaly fault detection system

We investigate the performance of a novel hierarchical, distributed, multi-tier, multi-hierarchical, distributed, multi-tier, multi-window fault detection system, namely the Generalized Anomaly and Fault Threshold (GAFT) system. We have carried out extensive simulation experiments of network resource and service deterioration, under two kinds of challenging conditions: in the presence of increasing intensities of class-alien traffic congestion and for a fixed intensity of anomaly traffic, but of varying characteristics, i.e., the distribution of fault packet length and inter-arrival interval. The corresponding numerical results demonstrate that GAFT is very efficient and can reliably detect the soft fault with traffic anomaly intensity as low as three percent of the typical background traffic intensity. Moreover, while GAFT is sensitive to the characteristics of the distributions that shape the fault under observation, it is very powerful in discerning even the most challenging cases, when the fault has very similar defining distribution characteristics to the prevailing background.
Agent Virtual Machine for Shipboard Automation Systems

We are interested in providing an agent infrastructure for truly distributed control. Requirements include multiple language implementations so that this agent host environment can exist in both real-time controllers and contain the ability to operate with external agent systems. Our first infrastructure, the Autonomous Cooperative System (ACS), accomplished these goals, but presented other issues. Although ACS has been successfully deployed on commercial controllers, new releases of controllers will cause complications in the evolution of the software and adoption of future functionality. We need to establish a formal integration procedure of the agent functionality with the controllers and to transform the underlying system into a fully integrated and open heterogeneous system. With an agent-enabled control firmware, we can make shipboard automation system o more distributed and survivable by essentially eliminating single point of failures.
A mobility-aware handoff trigger scheme for seamless connectivity in cellular networks

We present a mobility-aware handoff trigger mechanism that can predict the occurrence of a handoff well in advance of the actual event. Such a scheme could be used to provide smoother handoffs by enabling handoff procedures and pre-allocation of resources to be initiated prior to the actual handoff event. The handoff trigger scheme uses mobility information to predict the occurrence of a handoff event, i.e. the event when the pilot signal strength received from the target base station exceeds that received from the current base station by a given hysteresis level. The handoff trigger scheme is derived from a mobility estimation and prediction scheme, which is based on an autoregressive model or mobility. Simulation results show that the handoff trigger scheme can provide a non-trivial trigger interval with low probabilities of false alarm and missed detection.
Radiofrequency ablation for Barrett's esophagus and low-grade dysplasia in combination with an antireflux procedure: A new paradigm

Objective Radiofrequency ablation for Barrett's esophagus in combination with an antireflux procedure has not been widely documented. We report our initial experience with radiofrequency ablation in association with antireflux procedure for Barrett's metaplasia and low-grade dysplasia. Methods A total of 14 patients (10 male and 4 female patients) presented with Barrett's metaplasia (n = 11) or low-grade dysplasia (n = 3). Median age was 60 years (38–80 years). The severity of Barrett's esophagus was classified by length (in centimeters), appearance (circumferential/noncircumferential), and histology (1, normal; 2, Barrett's metaplasia; and 3, low-grade dysplasia). Radiofrequency ablation was performed with the HALO 360° or 90° systems (BARRX Medical, Sunnyvale, Calif). Results Median follow-up was 17 months. The mean number of ablative procedures undertaken was 2.6 (range, 1–6). There was no mortality, but there were 2 perioperative complications after the antireflux procedure (pneumonia, 1; atrial fibrillation, 1). One patient had mild dysphagia requiring a single dilation 2 months after ablation. The mean length of Barrett's esophagus decreased from 6.2 to 1.2 cm after treatment (P = .001). Barrett's grade decreased significantly (P = .003). Before therapy, circumferential Barrett's esophagus was present in 13 patients. At last endoscopy, only 1 patient had circumferential Barrett's esophagus present. The number of radiofrequency ablation treatments was significantly (P Conclusions Radiofrequency ablation performed either before or after an antireflux procedure is safe. This approach is effective for reducing or eliminating metaplasia and dysplasia. Long-term studies will be necessary to determine whether this approach can provide durable control of both reflux and Barrett's esophagus.
Scalable, updatable predictive models for sequence data

The emergence of data rich domains has led to an exponential growth in the size and number of data repositories, offering exciting opportunities to learn from the data using machine learning algorithms. In particular, sequence data is being made available at a rapid rate. In many applications, the learning algorithm may not have direct access to the entire dataset because of a variety of reasons such as massive data size or bandwidth limitation. In such settings, there is a need for techniques that can learn predictive models (e.g., classifiers) from large datasets without direct access to the data. We describe an approach to learn from massive sequence datasets using statistical queries. Specifically we show how Markov Models and Probabilistic Suffix Trees (PSTs) can be constructed from sequence databases that answer only a class of count queries. We analyze the query complexity (a measure of the number of queries needed) for constructing classifiers in such settings and outline some techniques to minimize the query complexity. We also show how some of the models can be updated in response to addition or deletion of subsets of sequences from the underlying sequence database.
Interfaces for palmtop image search

Will current technology support search for video news or entertainment on mobile platforms? An Ipaq palmtop version of the Informedia Digital Video Library interface has already been developed at the Chinese University of Hong Kong. For these displays, the desktop technique of showing a large grid of images in parallel is not feasible. Perceptual psychology experiments suggest that time-multiplexing may be as effective as space-multiplexing for this kind of primed recognition task. In fact, it has been specifically suggested that image retrieval interfaces using Rapid Serial Visual Presentation (RSVP) may perform significantly better than parallel presentation even on a desktop computer [2]. In our experiments, we did not find this to be true. An important difference between previous RSVP experiments and our own is that image search engines rank retrievals, and correct answers are more likely to occur early in the list of results. Thus we found that scrolling (and low RSVP presentation rates) led to better recognition of answers that occur early, but worse for answers that occur far down the list. This split confounded the global effects that we hypothesized, yet in itself is an important consideration for future interface designs, which must adapt as search technology improves.
Racial Segregation and the Black/White Achievement Gap, 1992 to 2009

In this study, we draw on longitudinal, state-level data to analyze the impact of four distinct forms of school racial segregation on black/white achievement gaps in math and reading. Pooled time-series analyses with two-way fixed effects suggest that increases in black‐white dissimilarity and black student isolation contribute to black/white achievement gaps, increases in black‐white exposure reduce achievement gaps, and increases in exposure of black students to other minority students have no impact. We conclude by discussing the implications of school racial segregation as a source of academic achievement disparities between black and white students in the contemporary United States. In the contemporary United States, the educational achievement gap between white and black students constitutes an important barrier to black/white economic equality (Jencks and Phillips 1998). Why do black students tend to achieve at lower levels than white students on average? Scholars have offered a number of answers, pointing to factors ranging from inequalities in students’ social class backgrounds to differences in cultural orientations toward schooling to various inequalities between and within schools themselves (Rothstein 2004; Downey 2008; Oates 2009). In this study, we address the impact of a phenomenon that, in our view, constitutes a primary suspect but has not received adequate theoretical or empirical attention in the recent literature: the fact that black and white students in the United States by and large do not attend the same schools. The larger significance of school segregation and achievement disparities cannot be overstated. Racial inequality, particularly the economic divide between blacks and whites, remains deeply entrenched in U.S. society. Compared with whites, blacks have
Dating deception: Gender, online dating, and exaggerated self-presentation

This study examined how differences in expectations about meeting impacted the degree of deceptive self-presentation individuals displayed within the context of dating. Participants filled out personality measures in one of four anticipated meeting conditions: face-to-face, email, no meeting, and a control condition with no pretense of dating. Results indicated that, compared to baseline measures, male participants increased the amount they self-presented when anticipating a future interaction with a prospective date. Specifically, male participants emphasized their positive characteristics more if the potential date was less salient (e.g., email meeting) compared to a more salient condition (e.g., face-to-face meeting) or the control conditions. Implications for self-presentation theory, online social interaction, and online dating research will be discussed.
Reduced Delay Uncertainty in High Performance Clock Distribution Networks

The design of clock distribution networks in synchronous digital systems presents enormous challenges. Controlling the clock signal delay in the presence of various noise sources, process parameter variations, and environmental effects represents a fundamental problem in the design of high speed synchronous circuits. A polynomial time algorithm that improves the tolerance of a clock distribution network to process and environmental variations is presented in this paper. The algorithm generates a clock tree topology that minimizes the uncertainty of the clock signal delay to the most critical data paths. Strategies for enhancing the physical layout of the clock tree to decrease delay uncertainty are also presented. Application of the methodology on benchmark circuits demonstrates clock tree topologies with decreased delay uncertainties of up to 90%. Techniques to enhance a clock tree layout have been applied on a set of benchmark circuits, yielding a reduction in delay uncertainty of up to 48%.
Insulin Resistance, Ceramide Accumulation and Endoplasmic Reticulum Stress in Experimental Chronic Alcohol-Induced Steatohepatitis

Aims: Chronic alcohol abuse causes steatohepatitis with insulin resistance, which impairs hepatocellular growth, survival and metabolism. However, growing evidence supports the concept that progressive alcohol-related liver injury may be mediated by concurrent mal-signaling through other networks that promote insulin resistance, e.g. pro-inflammatory, pro-ceramide and endoplasmic reticulum (ER) stress cascades. Methods: Using the Long Evans rat model of chronic ethanol feeding, we characterized the histopathologic and ultrastructural features of steatohepatitis in relation to biochemical and molecular indices of tissue injury, inflammation, insulin resistance, dysregulated lipid metabolism and ER stress. Results: Chronic steatohepatitis with early chicken-wire fibrosis was associated with enlargement of mitochondria and disruption of ER structure by electron microscopy, elevated indices of lipid storage, lipid peroxidation and DNA damage, increased activation of pro-inflammatory cytokines, impaired signaling through the insulin receptor (InR), InR substrate-1, Akt, ribosomal protein S6 kinase and proline-rich Akt substrate 40 kDa, glycogen synthase kinase 3β activation and constitutive up-regulation of ceramide and ER stress-related genes. Liquid chromatography coupled with tandem mass spectrometry demonstrated altered ceramide profiles with higher levels of C14 and C18, and reduced C16 species in ethanol-exposed livers. Conclusion: The histopathologic and ultrastructural abnormalities in chronic alcohol-related steatohepatitis are associated with persistent hepatic insulin resistance and pro-inflammatory cytokine activation, dysregulated lipid metabolism with altered ceramide profiles and both ER and oxidative stress. Corresponding increases in lipid peroxidation, DNA damage and protein carbonylation may have contributed to the chronicity and progression of disease. The findings herein suggest that multi-pronged therapeutic strategies may be needed for effective treatment of chronic alcoholic liver disease in humans.