cssi/SciSciGPT-SciSciNet huggingface dataset:
Abstract 368: Increased Platelet Activity in HIV-Infected Subjects on Antiretroviral Therapy Is Inhibited with Low-Dose Aspirin

Introduction: HIV-infected adults are at increased risk for cardiovascular events and increased platelet activity may contribute to this risk. Hypothesis: Platelet activity measurements are increased in subjects with HIV on fully suppressive antiretroviral therapy (ART) and low-dose aspirin attenuates this increase in platelet activity. Methods: We studied platelet aggregation in 25 HIV infected subjects on ART with undetectable plasma HIV-1 RNA and median CD4 521 cells/mm 3 and 29 healthy HIV seronegative controls in response to submaximal adenosine diphosphate (ADP, 0.4uM), collagen (0.05ug/ml), epinephrine (0.1uM ), arachidonic acid (AA, 0.15mM) and without agonist (spontaneous platelet aggregation [SPA]). The effects of a 1-week course of aspirin 81mg daily on platelet activity were also investigated. Results are presented as median (interquartile range) and analyzed using the Mann-Whitney U test. Results: Compared to controls, subjects with HIV had increased platelet aggregation in response to ADP (13.5% [6.8, 81.6] vs 6.4% [2.8, 10.7], p Conclusions: Baseline platelet activity is increased in subjects with HIV infection virologically suppressed on ART which may contribute to the excess cardiovascular risk commonly observed in this population. Subjects with HIV experienced greater decreases in platelet activity in response to aspirin, retaining modestly more platelet activity compared to controls. Cardiovascular prevention studies of aspirin in subjects with HIV are warranted.
Open Extensible System for Dynamic Problem Creation for Computer Science (Abstract Only)

There is good evidence that students learn better when given more opportunity to practice skills using related problems. However, this requires a sufficient supply of automatically graded problems to enable instant feedback. This can be achieved through automating the process of problem generation. While a few dynamic problem generation systems exist, they are either very specific to a single topic (such as tools for automatic generation of parameterized questions for Java or C programming or they are intended for other disciplines and not easily adapted to the needs of Computer Science. We have developed a prototype system for authoring, administering, and grading dynamic problems. This system is specifically designed for computer science. To this end, it supports complex logic, calling external programs such as compilers or databases, and the creation and manipulation of figures and diagrams. Problems and useful code libraries can be created and shared between instructors. It is a web-based system where instructors can specify problems by combining static text or images with bits of Lua code which add dynamism. When students use the system, their answers will be graded automatically, and they will be able to see the results, thus giving them quicker feedback. This is an integrated portion of a larger gamified learning platform called OneUp which is under development and aims to combine hands-on practicing with additional game-like motivational mechanisms. The goal of both the larger platform and the dynamic problems in specific is to increase student engagement in the learning process.
The Politics of the Glen Canyon Dam: Challenging the Status Quo of Water Policy in the West

The struggle to appropriate Colorado River water, while striving to mitigate the negative impacts of doing so, embodies the very essence of Western water policy. One of its defining controversies is over the Glen Canyon Dam at Lake Powell. During the past decade, groups and individuals have openly opposed the presence and operation of the Glen Canyon Dam. These groups claim that the environmental and cultural costs of the dam outweigh its benefits. State and federal decision makers presently think otherwise. The purpose of this paper is to identify and analyze the actors who are striving to influence policy on the Glen Canyon Dam, their specific arguments, and the effects their efforts have had or likely will have. The paper concludes that while support for the proposal to decommission the dam is growing, it appears unlikely that any political decision to do so will occur in the near future.
Dynamic Evaluation of Two Decades of CMAQ Simulations over the Continental United States

This paper focuses on dynamic evaluation of the CMAQ model over the continental United States using multi-decadal simulations for the period from 1990 to 2010 to examine how well the changes in observed ozone air quality induced by variations in meteorology and/or emissions are simulated by the model. We applied the anomalies method where changes in observed and modeled 4th highest, 95th, 90th and 85th percentile of summertime (May–September) daily maximum 8-h (DM8HR) ozone concentrations are compared for all monitoring stations in the USA. We also applied spectral decomposition of ozone time-series using the KZ filter to assess variations in the strengths of synoptic (weather-induced variations) and baseline (long-term variation forcings), embedded in the simulated and observed concentrations. The results reveal that CMAQ captured the year-to-year variability (more so in the later years than the earlier years) and the synoptic forcing in accordance with what the observations are showing. We examine methods to identify the strengths of the model in representing the changes in simulated O3 air quality over this period that can guide the development of approaches for a more robust analysis of emission reduction scenarios.
Genetic Models of Parkinson's Disease

Abstract Parkinson's disease (PD) is the most common neurodegenerative movement disorder in the United States. Although the disease can either be inherited or arise spontaneously, only 10–20% of all PD cases arise from inherited mutations. Despite this discrepancy, modeling PD in animals by means of genetic manipulations has significantly advanced our understanding of the pathogenesis of this disease. In this chapter, we provide a comprehensive review of the pathological, neurochemical, and behavioral phenotypes in mouse genetic models of PD. We discuss the incidence of given polymorphisms in PD patients and the nature of the mutations associated with inherited forms of the disease. Special attention is paid to the advantages and limitations of each model. Lastly, we identify groups of animals with the greatest utility in identifying environmental agents that may alter the course of PD-associated symptoms.
Duration of Antibiotic Use Among Adults With Uncomplicated Community-Acquired Pneumonia Requiring Hospitalization in the United States.

Background Previous studies suggest that duration of antibiotic therapy for community-acquired pneumonia (CAP) often exceeds national recommendations and might represent an important opportunity to improve antibiotic stewardship nationally. Our objective was to determine the average length of antibiotic therapy (LOT) for patients treated for uncomplicated CAP in US hospitals and the proportion of patients with excessive durations. Methods Records of retrospective cohorts of patients aged 18-64 years with private insurance and aged ≥65 years with Medicare hospitalized for CAP in 2012-2013 were used. Inpatient LOT was estimated as a function of length of stay. Outpatient LOT was based on prescriptions filled post discharge based on data from outpatient pharmacy files. Excessive duration was defined as outpatient LOT >3 days. Results Inclusion criteria were met for 22128 patients aged 18-64 years across 2100 hospitals and 130746 patients aged ≥65 years across 3227 hospitals. Median total LOT was 9.5 days. LOT exceeded recommended duration for 74% of patients aged 18-64 years and 71% of patients aged ≥65 years. Patients aged 18-64 years had a median (quartile 1-quartile 3) 6 (3-7) days outpatient LOT and those aged ≥65 years had 5 (3-7) days. Conclusions In this nationwide sample of patients hospitalized for CAP, median total LOT was just under 10 days, with more than 70% of patients having likely excessive treatment duration. Better adherence to recommended CAP therapy duration by improving prescribing at hospital discharge may be an important target for antibiotic stewardship programs.
Mitigating Forwarding misbehaviors in RPL-based low power and lossy networks

Low power and lossy networks (LLNs) are rapidly emerging as an important part of ubiquitous computing, and serving as a major building block for the communication infrastructure in the presence of Internet-of-Things (IoT). Routing protocol for low power and lossy networks (RPL) is a novel routing protocol standardized to enable the integration of resources-constrained devices into the Internet. However, due to the shared radio medium, the lack of physical protection and security requirements of inherent routing protocol, low power and lossy networks are admittedly threatened by diverse Denial-of-Service (DoS) attacks that primarily disrupt network protocols and interfere with on-going communications. In this paper, we propose a monitor-based approach, called CMD, to mitigate forwarding misbehaviors in LLNs running with RPL, where single or multiple malicious nodes randomly or strategically drop any incoming Data packet. The basic idea of the CMD is that each node monitors the forwarding behaviors of the preferred parent node to observe the packet loss rate, compares the observation result with the collected packet loss rate from one-hop neighbor nodes, and detects the forwarding misbehaviors of the preferred parent node. We evaluate the proposed scheme through extensive simulation experiments using OMNeT++ and compare its performance with the original RPL protocol and the existing two-step detection scheme. The simulation results show that the proposed scheme can not only improve the detection rate and packet delivery ratio (PDR) but also can reduce the energy consumption and isolation latency.
Advice on Specific Styles of Filming

The last few chapters expanded discussions about the basics of filming to greater details – composition, light, steady hands, focal length, angles, and so much more. These are the foundations for capturing persuasive clips. Helpful hints and directions go a long way when filming; however, there is more to filming than just understanding how to use your quiver or manipulating your environment. The kind of media that you weave into your movie (e.g., video interviews, animations, fieldwork, landscapes, photos, or narrations) creates a relationship with a viewer. Hopefully your choice of media helps to strengthen your story. Because of the large influence of media-type on how films affect audiences, specific media-type may be more appropriate for one style of film over others. Here we will delve into some of the methods behind filming interviews, landscapes, stop motion animation, news reports , and screenplays . There are a number of other film types, but these represent a great staging point to move forward with the films that you have in mind.
Intertrochanteric femoral osteotomies for developmental and posttraumatic conditions.

Despite the numerous advances in technology and techniques for total hip arthroplasty, this surgery is often not the procedure of choice for all patients or for all hip conditions. Originally described as a treatment for femoral neck nonunions, the intertrochanteric femoral osteotomy retains an enduring role in the treatment of various posttraumatic and developmental hip conditions including femoral neck nonunions, iatrogenic or postsurgical deformities, leg-length inequality, osteonecrosis, slipped capital femoral epiphysis, deformities occurring after Legg-Calve-Perthes desease, and for certain patients with dysplasia and secondary arthritis. By correcting deformity (either acquired or developmental), the intertrochanteric osteotomy can restore a more normal biomechanical geometry to the hip joint, which can increase the likelihood of improved longevity of the articulation. Excellent results have been reported by numerous authors using this procedure alone or in association with simultaneous or staged osteotomy of the pelvis. Factors that are common to most successful series are an emphasis on proper patient selection, detailed preoperative step-by-step planning, and meticulous intraoperative technique. Surgical intervention prior to the development of irreversible articular deterioration may result in dramatic short-term relief of pain because of improvements in biomechanics and relief of impingement. Long-term results include elimination of the need for total hip arthroplasty or postponement o f the need for this surgery for a meaningful number of years (such as 10 years or more).
The ConceptMapper Approach to Named Entity Recognition

ConceptMapper is an open source tool we created for classifying mentions in an unstructured text document based on concept terminologies and yielding named entities as output. It is implemented as a UIMA 1 (Unstructured Information Management Architecture (IBM, 2004)) annotator, and concepts come from standardised or proprietary terminologies. ConceptMapper can be easily configured, for instance, to use different search strategies or syntactic concepts. In this paper we will describe ConceptMapper, its configuration parameters and their trade-offs, in terms of precision and recall in identifying concepts in a collection of clinical reports written in English. ConceptMapper is available from the Apache UIMA Sandbox, using the Apache Open Source license.
Acoustics and Gas in Sediments: Applied Research Laboratories (ARL) Experience

A discussion of the acoustical properties of saturated sediments and of gas bubbles in water is given as background to a discussion of the present state of knowledge of the acoustical properties of gas bearing sediments.
Googling in Fear: Measuring Moral Panic Using Internet Searches Before and After Obama’s 2008 Election

ABSTRACTThe rhetoric, rumor, and hostility that surrounded the election of Barack Obama in 2008 appeared to correspond with the notion of a “moral panic.” However, systematically measuring phenomen...
Alterations in the Β-catenin pathway in non-small cell lung cancer to define a distinct molecular subtype with prognostic and therapeutic implications.

11584Background: The treatment of non-small cell lung cancer (NSCLC) has been revolutionized by the development of targeted therapy for distinct molecular subsets. Activation of the β-catenin pathw...
Effects of Estrogen Treatment on Aging in the Rat Epididymis

Previous studies from our laboratory demonstrated that estrogen signaling in the testis contributes to maintaining spermatogenesis in adult rats, and that estrogen treatment attenuated the age-associated decline in sperm production. The purpose of this study was to determine if epididymal function is also altered with age, and what effects estrogen treatment may have on the epididymis during aging. We compared untreated rats at 3 and 15 months of age to 18-month-old vehicle-treated and estrogen treated rats. In all four groups, tubule and lumen diameter of the cauda was significantly larger than more proximal regions of the epididymis. In the 3-, 15-, and 18-month-old treated animals, the epithelial cell height of the cauda was significantly shorter than that of more proximal regions. The caput cell height was shorter at 18 months compared to 3 months but this was not seen in estrogen treated animals. Thus, estrogen appears able to prevent some age related changes in epididymal morphology. Sperm transit time through the distal cauda was significantly delayed with aging. Estrogen treatment prevented this delay, indicating that sperm transit through the epididymis is an estrogen regulated function. Differences in estradiol and testosterone concentrations were observed between 3- and 15-month-old animals, but no further differences were noted between treated or untreated animals at 18 months. Interestingly, expression of androgen receptor and estrogen receptor alpha were similar between ages and treatments. Collectively, these results suggest epididymal morphology and function are affected by aging and estrogen treatment. Anat Rec, 302:1447-1457, 2019. © 2018 Wiley Periodicals, Inc.
Molecular genetic research into carbamoyl-phosphate synthase I: Molecular defects and linkage markers

Deficiency of the hepatic enzyme carbamoyl-phosphate synthase I (CPSI), results in lethal or near-lethal hyperammonaemia. As part of our work on CPSI deficiency we have explored the development of markers for prenatal diagnosis, and the determination of molecular defects resulting in CPSI deficiency. We have determined a set of highly informative microsatellite markers flanking the CPSI gene. We have found 14 mutations in individuals with CPSI deficiency. During our mutation studies, we have made extensive use of cell lines not normally expressing CPSI through amplification of 'illegitimate' transcripts. We summarize these findings and review our current understanding of this important enzyme.
Applying Public Participation Geographic Information Systems for coastal wading bird conservation

Coastal estuaries in the northern Gulf of Mexico are important habitat for wading birds, but are threatened by land use and ecological changes. Conservation has been demonstrated to be more effecti...
Concentrations of sulphated estrone, estradiol and dehydroepiandrosterone measured by mass spectrometry in pregnant mares

BACKGROUND Few studies have provided a longitudinal analysis of systemic concentrations of conjugated oestrogens (and androgens) throughout pregnancy in mares, and those only using immunoassay. The use of liquid chromatography tandem mass spectrometry (LC-MS/MS) will provide more accurate concentrations of circulating conjugated steroids. OBJECTIVES To characterise circulating concentrations of individual conjugated steroids throughout equine gestation by using LC-MS/MS. STUDY DESIGN Longitudinal study and comparison of pregnant mares treated with vehicle or letrozole in late gestation. METHODS Sulphated oestrogens and androgens were measured in mares throughout gestation and mares in late gestation (8-11 months) treated with vehicle or letrozole to inhibit oestrogen synthesis in late gestation. An analytical method was developed using LC-MS/MS to evaluate sulphated estrone, estradiol, testosterone and dehydroepiandrosterone (DHEAS) during equine gestation. RESULTS Estrone sulphate concentrations peaked by week 26 at almost 60 μg/mL, 50-fold higher than have been reported in studies using immunoassays. An increase in DHEAS was detected from 7 to 9 weeks of gestation, but concentrations remained consistently low (if detected) for the remainder of gestation and testosterone sulphate was undetectable at any stage. Estradiol sulphate concentrations were highly correlated with estrone sulphate but were a fraction of their level. Concentrations of both oestrogen sulphates decreased from their peak to parturition. Letrozole inhibited estrone and estradiol sulphate concentrations at 9.25 and 10.5 months of gestation but, no increase in DHEAS was observed. MAIN LIMITATIONS Limited number of mares sampled and available for analysis, lack of analysis of 5α-reduced and B-ring unsaturated steroids due to lack of available standards. CONCLUSIONS Dependent on methods of extraction and chromatography, and the specificity of primary antisera, immunoassays may underestimate oestrogen conjugate concentrations in blood from pregnant mares and may detect androgen conjugates (neither testosterone sulphate nor DHEAS were detected here by LC-MS/MS) that probably peak coincident with oestrogen conjugates between 6 and 7 months of equine gestation.
Where Do You Stand? Discussions That Promote Democratic Citizenship and Engage Multiple Intelligences:

Teachers often desire meaningful classroom discussions, but frequently shy away from introducing controversial topics. An instructional activity “Where Do You Stand?” was developed and used regular...
A model for high temperature deformation of nanolaminate Cu-Nb composites

Abstract Nanolaminate composites with layer thicknesses down to 65 nm display conventional 3 stage creep behavior with creep resistance increasing as layer thickness decreases. A model for the time dependent high temperature deformation response of Cu-Nb composites is developed, and compared to creep tests performed on multilayers fabricated via accumulative roll bonding (ARB). The model assumes a continuous laminate structure of 50% Cu and 50% Nb in which deformation is controlled by stage II creep for the copper ( e ˙ c r = A σ n ) and plasticity in Nb. Regimes in which composite steady-state creep at constant stress can be achieved are identified. The modeling illustrates that strain-hardening in the niobium plays a critical role in the transient response of the multilayer, which can dominate the creep lifetime. The combination of experiments and models strongly suggest that dislocation climb mechanisms in the copper control the time-response at 400 ∘C for all layer thicknesses tested.
“Nothing About Us Without Us”: Reading Protests against Oppressive Knowledge Production as Guidelines for Solidarity Research:

Drawing from my analysis of sex worker and homeless protests as well as my experience doing ethnographic research with people experiencing homelessness and people in the sex trade, I put forth reco...
Spectroscopic inference of alkane, alkene, and aromatic formation during high-temperature JP8, JP5, and Jet-A pyrolysis

Abstract The speciation of jet-fuel pyrolysis plays an important role in the development of predictive models for jet-fuel combustion. In this work, a multi-wavelength speciation technique was applied to a large dataset of shock-tube laser-absorption measurements of jet-fuel pyrolysis. A novel absorbance model was developed to interpret the measurements at common conditions, and pyrolysis product time-histories and early-time yields are reported for three jet fuels at five high-temperature conditions. Specifically, methane, ethylene, and lumped vinyl-group time-histories, in addition to aromatics (benzene and toluene) yields, were quantified using eight wavelengths over conditions 1040–1480 K, 1–3 atm, for jet fuels JP8, Jet-A, and JP5. Results are presented at 1150 K, 1200 K, 1250 K, 1300 K, and 1350 K. Additional relationships between vinyl-group-containing species, namely propene, 1-butene, and 1,3-butadiene, are explored. The mole fraction time-histories exhibit good agreement with the literature and extend the speciation of these jet fuels to the limits of current spectroscopic techniques.
Chapter 5 – Reactor Kinetics

Publisher Summary This chapter examines the time-dependent behavior of neutron chain reactions. In order to emphasize the time variable, two simplifications are made in the chapter that remove the need to treat the neutron energy and spatial variables concomitantly. The chapter begins by introducing a series of neutron balance equations and their time-dependent behavior. A system is examined in which no fissionable materials are present; such a system is designated as nonmultiplying. Then fissionable isotopes are included, and the behavior of the resulting multiplying system is examined. In both cases, it is assumed that neutron leakage from the systems can be ignored. The effects of leakage are then incorporated in order to examine the phenomena of criticality in systems of finite size. The chapter explains in detailed the topics of multiplying systems behavior, delayed neutron kinetics, and step reactivity changes. The chapter also deals with the reactor kinetics that results from the combined effects of fission neutrons, both those produced promptly and those that are delayed.
Early Constraints on the Imagination: The Realism of Young Children

The imagination of young children has notable constraints. The outcomes and possibilities that they imagine rarely deviate from the everyday regularities they have observed and remembered. Their reality-based imagination is evident in a variety of contexts: early pretend play, envisioning the future, judgments about what is possible, the instructive role of thought experiments, tool making, and figurative drawing. Overall, the evidence shows that children's imagination helps them to anticipate reality and its close alternatives. This perspective invites future research on the scope of children's thinking about counterfactual possibilities, their ability to make discoveries about reality on the basis of thought experiments, and the ways in which cultural input can expand the scope of the possibilities that they entertain.
Visualizing 3D imagery by mouth using candy-like models.

Handheld models help students visualize three-dimensional (3D) objects, especially students with blindness who use large 3D models to visualize imagery by hand. The mouth has finer tactile sensors than hand, which could improve visualization using microscopic models that are portable, inexpensive, and disposable. The mouth remains unused in tactile learning. Here, we created bite-size 3D models of protein molecules from “gummy bear” gelatin or nontoxic resin. Models were made as small as rice grain and could be coded with flavor and packaged like candy. Mouth, hands, and eyesight were tested at identifying specific structures. Students recognized structures by mouth at 85.59% accuracy, similar to recognition by eyesight using computer animation. Recall accuracy of structures was higher by mouth than hand for 40.91% of students, equal for 31.82%, and lower for 27.27%. The convenient use of entire packs of tiny, cheap, portable models can make 3D imagery more accessible to students.
Domestic Taxes and Inbound Acquisitions

US corporations face higher tax burdens than those in many other countries, potentially influencing merger and acquisition activity. A theoretical model of this process yields two testable implications: that, relative to high-tax domestic bidders, low-tax foreign bidders will specialize in both high profitability target firms and those with few tax deductions. I find support for both effects in the US acquisition market using cross-sectional variation in target profitability and industry-level variation in deductions from bonus depreciation tax reform. Counterfactual simulations show that this reform induced a large drop in foreign acquisitions and a significant loss of aggregate wealth.
Regulating Firearms as a Consumer Product

Motor vehicles are the leading cause of injury death in the United States; firearms are the second. Unlike motor vehicles, firearms are not subject to governmental consumer product standards. A survey of 1204 U.S. adults found substantial support (74.9%) for government safety standards for firearms. Child-proofing and personalizing handguns and congressional hearings into the firearms industry also were popular. A slight majority favored banning inexpensive, easily concealed handguns known as Saturday Night Specials. Just over one-third favored suing firearm manufacturers or banning personal possession of handguns. Full benefit from any firearm design modification will likely take years to materialize.
Computer Simulations of Nonthermal Particles in Clusters of Galaxies: Application to the Coma Cluster

We have developed a numerical model for the temporal evolution of particle and photon spectra resulting from nonthermal processes at the shock fronts formed in merging clusters of galaxies. Fermi acceleration is approximated by injecting power-law distributions of particles during a merger event, subject to constraints on maximum particle energies. We consider synchrotron, bremsstrahlung, Compton, and Coulomb processes for the electrons, nuclear, photomeson, and Coulomb processes for the protons, and knock-on electron production during the merging process. The broadband radio through $\gamma$-ray emission radiated by nonthermal protons and primary and secondary electrons is calculated both during and after the merger event. To test the ability of the computer model to accurately calculate the nonthermal emission expected from a cluster merger event, we apply the model to the Coma cluster of galaxies, and show that the centrally located radio emission and the Hard X-ray excess observed at 40-80$\kev$ is well fit by our model. If our model is correct, then the Coma cluster will be significantly detected with GLAST and ground-based air Cherenkov telescopes.
Evaluation of an inexpensive depth camera for in-home gait assessment

An investigation of a new, inexpensive depth camera device, the Microsoft Kinect, for passive gait assessment in home environments is presented. In order to allow older adults to safely continue living in independent settings as they age, the ability to assess their risk of falling, along with detecting the early onset of illness and functional decline, is essential. Daily measurements of temporal and spatial gait parameters would greatly facilitate such an assessment. Ideally, these measurements would be obtained passively, in normal daily activity, without the need for wearable devices or expensive equipment. In this work, the use of the inexpensive Microsoft Kinect for obtaining measurements of temporal and spatial gait parameters is evaluated against an existing web-camera based system, along with a Vicon marker-based motion capture system for ground truth. Techniques for extracting gait parameters from the Kinect data are described, as well as the potential advantages of the Kinect over the web-camera system for passive, in-home gait assessment.
Pipeline and Parallel-Pipeline FFT Processors for VLSI Implementations

In some signal processing applications, it is desirable to build very high performance fast Fourier transform (FFT) processors. To meet the performance requirements, these processors are typically highly pipelined. Until the advent of VLSI, it was not possible to build a single chip which could be used to construct pipeline FFT processors of a reasonable size. However, VLSI implementations have constraints which differ from those of discrete implementations, requiring another look at some of the typical FFT'algorithms in the light of these constraints.
Modelling the urban future: planning, slums and the seduction of growth in St Louis, 1940–1950

This paper considers the attempts by planners during and after World War II to forecast population change for the purposes of long‐range planning. St Louis is used as a case study to examine the social, economic and political contexts within which decisions about how to map the city’s future were made. At the heart of the problem is the adoption by the city of a growth model to justify a large‐scale slum clearance agenda at the very moment when the city was poised for catastrophic population loss. It is argued that planners allowed themselves to be caught up in the momentary crisis of a wartime population spike, ultimately ignoring their own frequent warnings about underlying trends toward population decline. Within this post‐war crisis of temporary overcrowding, planners made the critical decision to move ahead with slum clearance projects of unprecedented scale. Unfortunately, by the time their projects were complete, the city for which they had been undertaken no longer existed.
Collapse dynamics of super-Gaussian beams

We investigate the self-focusing dynamics of super-Gaussian optical beams in a Kerr medium. We find that up to several times the critical power for self-focusing, super-Gaussian beams evolve towards a Townes profile. At higher powers the super-Gaussian beams form rings which break into filaments as a result of noise. Our results are consistent with the observed self-focusing dynamics of femtosecond laser pulses in air [1] in which filaments are formed along a ring about the axis of the initial beam where the initial beam did not form a ring.
Ageing Characteristics of the Weibull Mixtures

It is well known that mixtures of decreasing failure rate (DFR) distributions have the DFR property. A similar result is, of course, not true for increasing failure rate (IFR) distributions. In a recent note, Gurland and Sethuraman (1994, Technometrks36(4): 416–418) presented two examples where mixtures of IFR distributions show DFR property. In this paper, we present a general approach to study the mixtures of distributions and show that the failure rates of the unconditional and conditional distributions cross at most at one point. Mixtures of Weibull distribution with a shape parameter greater than 1 are examined in detail. This also enables us to study the monotonic properties of the mean residual life function of the mixture. Some examples are provided to illustrate the results.
Influence of prior fasciotomy on infection after open reduction and internal fixation of tibial plateau fractures.

Background: High-energy tibial plateau fractures may present with an acute or impending compartment syndrome requiring emergent fasciotomy. There is little information regarding the optimal management of the fasciotomy wound with respect to the subsequent definitive internal fixation of the tibial plateau fracture. The purpose of this study was to compare the rate of infection complication after internal fixation of tibial plateau fractures in patients requiring fasciotomy for compartment syndrome with patients in whom a fasciotomy was not required. Methods: We retrospectively reviewed all tibial plateau fractures presenting over a 55-month period. Fourteen patients who presented with an associated compartment syndrome requiring fasciotomy and 128 patients in whom a fasciotomy was not performed met inclusion criteria. Patients age, sex, mechanism of injury, management of their fasciotomy, operative treatment of their plateau fracture, follow-up surgical procedures, follow-up complications, and length of follow-up were reviewed. Infection complications were defined as cellulitis requiring treatment with intravenous or oral antibiotics, patients requiring operative debridement after definitive fixation, and documentation of osteomyelitis. Results: In the fasciotomy group, two patients developed cellulitis that was treated with a short course on oral antibiotics. There were no documented deep infections. In the no fasciotomy group, eight patients (6.25%) had a documented culture-positive deep infection. Additionally, six patients had documented occurrences of cellulitis managed with oral or intravenous antibiotics. Conclusions: Definitive internal fixation of tibial plateau fractures in the presence of open fasciotomy wounds does not seem to be associated with an increased infection risk.
Priming in the brain, an immunologically privileged organ, elicits anti-tumor immunity.

A crucial question in the study of tumor neuro-immunology concerns the capacity of the central nervous system to initiate and execute an immune response. In a 100% fatal rat malignant glioma model, genetically modified tumors secreting INF-γ intracerebrally generate an immune response resulting in a substantial increase in survival time, tumor rejection and specific systemic immunity. Tumors modified to secrete IL-2 alone do not change the biologic behavior of transfected gliomas. INF-γ induces elevated expression of major-histocompatibility-complex-class-I and -class-II molecules in microglia throughout the brain and invokes enhanced tumor infiltration by CD4, CD8 and NK cells. These findings demonstrate successful immunization against a central-nervous-system tumor by direct priming in the brain with a live growth-competent tumor vaccine. Int. J. Cancer 75:266–276, 1998. © 1998 Wiley-Liss, Inc.
The solution structure of apo-iron regulatory protein 1.

Abstract Iron is a cofactor for many proteins that are involved in essential metabolic processes. However, iron must be strictly regulated because it can react with oxygen to generate cytotoxic reactive oxygen intermediates. Iron regulatory protein 1 (IRP1) is a bi-functional protein that can act either as a post-transcriptional regulator of mRNAs containing iron responsive elements, or as a [4Fe–4S] cluster-containing cytosolic aconitase. Previous X-ray crystallography results show that IRP1 is in an open L-shape conformation when bound to IRE-RNAs, and in a globular conformation when it binds an iron–sulfur cluster. The structure of apo-IRP1 and the mechanism by which it transforms to either functional state is unknown. Therefore, small angle X-ray scattering was used to determine the low resolution solution structure of apo-IRP1 and to characterize its biophysical properties. These results show that apo-IRP1 has a radius of gyration (Rg) of 33.6 ± 0.3 A, and a Dmax of 118 ± 2 A. The ab initio and rigid-body modeling results show that apo-IRP1 is in an open conformation in solution, and the ensemble optimization results show that the molecules stay narrowly distributed about a Rg of 33–34 A. The open apo-IRP1 conformation seems optimal for subsequent conversion to either functional end state: RNA-binding, or cytosolic aconitase.
Evolutionary divergence of mitochondrial dna from paramecium aurelia

Mitochondrial (mt) DNA from four sibling species within the Paramecium aurelia complex, including stocks of different geographic origin and mutants, were analyzed using four 6-bp recognition site and one 4-bp recognition site endonucleases and the sequence divergence was estimated using Upholt's (1977) statistical procedure. All four species were readily distinguishable regardless of the restriction endonuclease employed. With intraspecies comparisons, no differences were observed which could be accounted for on the basis of geographic origin. Except for species 4, each stock (and mutant) gave a species-specific fragment pattern. For species 4, while the patterns were distinct from the other species, two species-specific type of patterns were found, designated A and B. The sequence divergence between these was estimated to be between 1 and 2 percent. With interspecies comparisons, the sequence divergence ranged from 3.9 to 10.3% with the greatest divergence being between species 1 and 4, and the least between species 1 and 5. The similarity between species 1 and 5 is in accord with other criteria for interspecies comparisons. The degree of sequence divergence measured here in Paramecium mt DNA is well within the range reported for rodents and primates. All four species mt DNA were cleaved to many DNA fragments by DPN II, an enzyme which recognizes non-methylated sites, and not by DPNI, the methyl-site specific counterpart of DPN II, suggesting that mt DNA from Paramecium aurelia is not appreciably methylated, if at all.
Ferromagnetism, superconductivity and secondary phases in the dilute magnetic semiconductor Pt1−xRExSb2 (RE = La, Ce, Gd, Yb)

We have measured the electrical transport, heat capacity, and magnetic properties of single crystals of semiconducting PtSb2, doped with rare earth ions. Carrier concentrations in the doped crystals range from 1017 to 1020 cm−3, and in most cases, metallic resistivity was observed. Moment densities of 1020–1023μB/cm3 were found for crystals doped with magnetic rare earths, and diamagnetic behavior for those doped with non-magnetic rare earths. Weak superconductivity and ferromagnetic order were observed separately in many of the doped crystals, and electron microscopy studies reveal that they likely originate with secondary surface phases. Accordingly, surface etching suppressed both the ferromagnetic and superconducting behaviors. Nonetheless, electrical transport and heat capacity measurements of the doped crystals suggest that the bulk electronic properties are modified relative to stoichiometric PtSb2, making this a potentially interesting system for studying magnetism in a low carrier density environment.
Sensory thresholds, response biases, and the neural quantum theory

Abstract Sensory differential thresholds are studied by models which partition the sensory process into two successive stages: a detection stage independent of motivational variables, and a decision stage which selects a response using the observer's motivations and expectations. The detection model considered is the neural quantum theory. Several decision models are applied to the detection model, and the existing psycho-physical literature relevant to thresholds is analyzed. Two aspects of the data, the psychometric function and isosensitivity curves (Receiver Operating Characteristic), are examined for three different experimental conditions: (1) the yes-no detection experiment; (2) the random presentation experiment; and (3) the two-alternative temporal forced-choice experiment. The observer's task is to decide whether a particular observation is caused by signal or noise. In one decision strategy, the rigid criterion, the observer reports a signal only if he detects an increase in the number of excited states of at leask k . Another decision strategy proposes a response bias: the observer reports a signal with probability t k if the number of excited states increases by exactly k . This model provides an explanation for the way in which the psychometric functions of quantum theory are transformed by changes in experimental procedure.
In vitro immunoglobulin production by mononuclear cells in rheumatoid arthritis

Since patients with rheumatoid arthritis (RA) exhibit serum hypergammaglobulinemia and autoantibody (rheumatoid factor) production, we compared elaboration and control of in vitro RA mononuclear cell (MNC), Ig assayed by enzyme-linked immunoassays or by hemolytic plaque formation, in 37 RA patients and 17 normal subjects. We found (1) RA spontaneous plaque-forming cells were significantly reduced (RA 344 vs normal 627 PFC/10(6) MNC, P less than 0.002); (2) RA spontaneous IgG and IgM (but not IgA) elaboration was significantly diminished (IgG RA 339, normal 776; IgM RA 255, normal 869 ng/ml, P less than 0.001; IgA RA 87, normal 124); (3) RA stimulated IgG and IgM production (but not IgA) was also decreased (IgG RA 2434, normal 3862, P less than 0.06; IgM RA, 1676, normal 3323, P less than 0.005; IgA RA 1859, normal 2315); (4) reduced RA Ig elaboration was not clearly due to altered numbers of T or non-T cells, age, medications, clinical features of disease, or response kinetics; (5) relative improvement of RA in vitro IgG, but not usually IgM, secretion followed removal of adherent cells, addition of indomethacin or addition of mitomycin C-treated T cells; (6) MNC from synovial fluids, but not bone marrows, exhibited spontaneous Ig production in excess of stimulated synovial fluid cellular or peripheral blood Ig elaboration. These observations indicate selective impairment of peripheral blood MNC IgG and, particularly, IgM secretion in RA. This defect appears to reflect accessory cell influences which differ from normal as well as the sequestration of primed or activated cells in the synovial fluid.
Tritium diffusion through oxide surface films on niobium

Abstract Diffusion of tritium in niobium has been investigated using recoil implantation with particular emphasis on the role of surface oxide films. In conformity with previously reported data, bulk diffusion in niobium is found to be extremely rapid and surface oxide films significantly retard the release rate of tritium. The observed tritium release data indicate diffusion through cracks or defects in the oxide film below 500°C and transport through an intact film at temperatures higher than 500°C. The release rates are described in terms of a mathematical model with the necessary model parameters determined from experimental data. The oxide films could be removed with a reducing hydrogen atmosphere, thereby resulting in classical bulk diffusion controlled release above 700°C. Below 700°C the oxide layers were stable in hydrogen, presumably because of a moderately high oxygen potential resulting from minute amounts of moisture in the sample chamber.
903–11 Sustained Inhibition of Intimal Thickening: Beneficial In Vitro and In Vivo Effects of Polymeric β-Cyclodextrin Sulfate

Intimal thickening after vascular injury is thought to be modulated in part by heparin binding growth factors. We hypothesized that placement of a therapeutic polymer in the periadventitial space capable of tightly binding growth factors might alter the vascular response to injury. We first tested the effects of polymeric β-cyclodextrin sulfate (P-CDS) on smooth muscle cell (SMC) proliferation using a quantitative protein accumulation assay. Incubation of rat aortic SMC (2500 cells/microwell in 10% FCS, n = 96) with P-CDS was associated with a dose dependent inhibition of proliferation, with maximum inhibition ≈50% vs. control at 1 mg/ml (p l 0.05). The proliferation assays were repeated using media containing only recombinant basic FGF (bFGF, 5 μg/ml) which had been exposed to P-CDS (1 mg/ml) for varying periods of time (1 min to 3 days). We demonstrated a time dependent reduction of the bFGF mitogenic activity, with complete removal of all activity within 60 minutes. Using radiolabeled bFGF (0.25 μg/ml), we observed rapid association (0.23 min-1) and dissociation (7.3 μ 10–5 min-1) rates, suggesting a high affinity interaction. We then tested the effects of P-CDS on SMC migration (using a linear under-agarose assay) and demonstrated treatment of rat aortic SMC with P-CDS (1 mg/ml) in the agar resulted in ≈50% reduction in SMC migration vs. control at 72 hours (p l 0.05). Finally, the effects of P-CDS in vivowere studied in the rat carotid balloon injury model. SD rats (l 350 g) were randomized to periadventitial P-CDS (10 mg) or no treatment, additional rats received treatment with unsulfated β-cyclodextrin polymer (PCD). Morphometric analyses at 4 (n = 20), 14 (n = 59), and 88 days (n = 14) demonstrated g40% reduction of intimal area and intima/media area ratios only in the P-CDS rats. No inhibition was seen with P-CD treated rats. Decreased bromodeoxyuridine labeled SMC (79 ± 11 vs 144 ± 23, p = 0.01) were noted in the intima of P-CDS rats at 14 days. At all time points, there were reduced total SMC counts and no reduction in % proliferation in the intima of P-CDS rats, suggesting greater effects on SMC migration than proliferation in vivo. Endothelial cell regrowth (by Evans blue staining) was increased in the P-CDS rats at 14 (4.4 vs 2.2 mm, p = 0.09) and 88 days (13.0 vs 9.2 mm, p l 0.01). Download : Download high-res image (57KB) Download : Download full-size image Conclusion Periadventitially applied polymeric β-cyclodextrin sulfate produces sustained inhibition of intimal thickening following vascular injury, possibly by modulating cellular processes mediated by heparin binding growth factors.
The Impact of Restricting the Flow of Inventory in Serial Production Systems

This research uses simulation technique to compare the output performance of pull production systems with different inter-station storage capacities (ISSC) under various levels of total inventory (INV) in the system, station coefficient of variation (CV), and station down-time (DT). There are two primary findings from this study. First, it shows pull systems with larger ISSC yield a significantly higher output at all levels of INV in the system, station CV, and station DT. Second, it shows that lines using a strict kanban-based pull system can increase output while decreasing WIP inventory simply by allowing the inventory to flow freely between stations. These are major findings considering that the modifications necessary in the system to achieve these results are fairly uncomplicated and should require minimal investment.
Internet demand under different pricing schemes

This research was supported by grants from the National Sci- ence Foundation, Cisco Systems, SBC Communications, the Califor- nia State MICRO Program and Hewlett-Packard.
Byte code level cross-compilation for developing web applications

JavaScript provides the technological foundation of Web 2.0 applications. AJAX (Asynchronous JavaScript And XML) applications have received wide-spread attention as a new way to develop highly interactive web applications. Breaking with the complete-page-reload paradigm of traditional web applications, AJAX applications rival desktop applications in their look-and-feel. But AJAX places a high burden on a web developer requiring extensive JavaScript knowledge as well as other advanced client-side technologies. In this paper, we introduce a technique that allows a developer to implement an application in Java or any.NET language and then automatically cross-compile it to an AJAX-enabled web application.