cssi/SciSciGPT-SciSciNet huggingface dataset:
Competition, Colonization Patterns, and Disturbance in Stream Benthic Communities

A major goal of research on the ecology of communities is to build an understanding of the mechanisms responsible for the distribution, abundance, and coexistence of the member species. The richness and complexity of benthic communities in streams has long been recognized but very few factors that influence these patterns are understood, A hierarchy of mechanisms responsible for the distribution and abundance of organisms exists within any community (Brown, 1981; Reynoldson, 1981). Ultimately, organisms in streams are limited to specific ranges of physical environments by their physiological tolerances to ranges of temperature, water chemistry, etc. (Fiance, 1978; Vannote and Sweeney, 1980). Within a suitable range of these physical limitations, organisms may be restricted to particular ranges of current velocities, substrate types, or food availability within which they can successfully procure food resources (Harrod, 1965; Edington, 1968; Carlsson et al., 1977; Malas and Wallace, 1977). In addition, predation, interspecific competition, and many kinds of physical disturbances may further restrict the distribution and abundance of individuals within otherwise suitable microhabitats.
A CS1 to CS2 bridge class using 2D game programming

Many students view our current CS1/CS2 sequence as abstract, boring, and hence too difficult. We present a new CS1 to CS2 bridge class developed and taught spring 2005. Our bridge class, perhaps called CS 1.5, uses 2D game programming in Flash ActionScript to solidify CS1 concepts, introduce concrete examples, introduce some new concepts such as graphics and event driven programming, and motivating the need for CS2. It is our hope that this class will better prepare students for CS2, increase their enthusiasm, and help retain majors.
The Role of Tobacco Cessation, Antiplatelet and Lipid-Lowering Therapies in the Treatment of Peripheral Arterial Disease

Despite the widely held belief that there are no effective medical therapies for peripheral arterial disease (PAD), current data suggest that medical therapies can effectively modify the natural history of atherosclerotic lower extremity arterial occlusive disease. The ideal medical therapy would improve claudication, forestall the onset of limb-threatening events, decrease rates of invasive interventional therapies and improve long-term patient survival. These ideal outcomes might be achieved through the use of smoking cessation interventions, including behavioral and pharmacological therapy, and the administration of antiplatelet and lipid-lowering medications in patients with PAD.
The Wetting of Solids by Liquid Hydrogen

The wetting of solids by liquid hydrogen Is of great Importance in space flight. Wetting effects determine the distribution of liquid hydrogen in a fuel tank under zero g, and also are involved in the prevention of vapor lock in lines from tank to pump. Questions of heat transfer, e.g., when nucleate or film boiling will start, are influenced by the wetting of solids by the liquid.
Dopamine Transporter in Aging

Both the maximal number of mazindol binding sites and the maximal velocity of DA uptake in striatum decline with age. The number of mazindol binding sites in young rats far exceed the minimum required for the maximal DA uptake. However, the mazindol-binding sites decline with age and, therefore, become a limiting factor in DA uptake in aged rats.
Alternative or Intentional? Towards a Definition of “Unusual” Communities

At the beginning of interviews Ayala Cnaan recently conducted in Israel, she offered subjects the opportunity to inquire about the background of her research project on intentional communities. One woman at a kibbutz wondered why her community was selected. After a brief explanation, the woman exclaimed, “What makes you think we’re ‘intentional’?”
Administering Public Participation

Participation and administration have long had an uneasy coexistence. On one hand, public participation in decisions that affect citizens is consistent with citizenship and democracy; on the other ...
Syntactic and Semantic Soundness of Structural Dataflow Analysis

We show that the classical approach to the soundness of dataflow analysis is with respect to a syntactic path abstraction that may be problematic with respect to a semantics trace-based specification. The fix is a rigorous abstract interpretation based approach to formally construct dataflow analysis algorithms by calculational design.
Electrothermal Characteristics of Delta-Doped $\beta$ -Ga 2 O 3 Metal–Semiconductor Field-Effect Transistors

A 2-D electrothermal model of delta-doped b eta-gallium oxide ( $\beta $ -Ga2O3) metal–semiconductor field-effect transistor (MESFET) is developed by using TCAD Sentaurus to investigate its electrical and thermal characteristics. The temperature and electric field-dependent electron mobility model is incorporated to predict I – V characteristics of the FET, which are in good agreement with the measured I – V characteristics. We investigated the effect of bias voltages on an electric field, a current path, a volumetric heat generation profile, and a peak temperature at a given total heat dissipation. The peak temperature is observed to be significantly different at the same power dissipation but different bias conditions, e.g., the peak temperature is ~9 K higher when the drain-to-source voltage ( V ds) = 25 V and the gate-to-source voltage ( V gs) = −6 V compared with V ds = 8.3 V and V gs = 2 V at the total power dissipation of 1.16 W/mm. This difference is attributed to the change in the electron Joule heating profile with the applied bias voltage. The effects of the location of the delta-doping layer, the gate–drain spacing, and the source–drain spacing are investigated to guide a future device fabrication. The variation in these parameters mainly affects electrical characteristics such as ON-resistance, saturation current, threshold voltage, and so on. The thermal characteristics, such as peak temperature, temperature profile, and so on, are not significantly affected at a low-power dissipation.
Morphine decreases the function of primary human natural killer cells by both TLR4 and opioid receptor signaling.

Abstract Background Opioids are commonly used to provide analgesia for cancer pain, and functional opioid receptors have been identified on natural killer (NK) cells, the lymphocytes responsible for surveillance and elimination of cancer cells. Opioids also bind to other lymphocyte receptors, such as Toll-like receptor (TLR)-4. Here, we characterized the effects of morphine on primary human NK cell cytotoxicity and mediator release, which occur through classical opioid receptor or TLR4 signaling. Methods Purified primary human NK cells were pretreated with inhibitors of opioid receptors or TLR4 before being cultured with target tumor cell line K562 in the presence or absence of morphine. Apoptosis of K562 cells in each treatment condition was measured with an Annexin V flow cytometry-based assay and compared to that of K562 cells cultured with NK cells alone. Supernatant concentrations of 13 cytokines and cytotoxic mediators were measured with a multiplex bead-based flow cytometry assay. Results Exposure of NK cells to morphine decreased their ability to induce apoptosis in K562 cells. Pretreating the NK cells with either naloxone, a mu- and kappa-opioid receptor antagonist, or TAK-242, a selective inhibitor of TLR4 signaling, prevented this effect. Paradoxically, morphine increased the concentration of interleukin-6, granzyme A, and granzyme B in cell supernatants. Pretreatment of NK cells with TAK-242 prevented the morphine-induced increase in interleukin-6, whereas pretreatment with naloxone inhibited the morphine-induced increase in granzymes A and B. Conclusions Both classical opioid receptors and TLR4 participate in morphine-induced suppression of NK cell cytotoxic activity. These studies have important implications for maintenance of immune function during management of cancer pain.
Progress in extracellular vesicle biology and their application in cancer medicine

Under the broader category of extracellular vesicles (EVs), exosomes are now well recognized for their contribution and potential for biomedical research. During the last ten years, numerous technologies for purification and characterization of EVs have been developed. This enhanced knowledge has resulted in the development of novel applications of EVs. This review is an attempt to capture the exponential growth observed in EV science in the last decade and discuss the future potential to improve our understanding of EVs, develop technologies to overcome current limitations, and advance their utility for human benefit, especially in cancer medicine. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.
Organic minerals restore the acid-base and electrolyte balance in broiler chicks with nutritionally induced metabolic acidosis

The present study evaluated the blood gas and electrolyte balance in broiler chicks fed with diets containing different levels of vitamin premix (VM) and forms of trace minerals. VM was included at...
Inpatient Child and Adolescent Psychiatry as an Extracurricular Venue for Medical Student and Resident Education and Professional Development: Story Time and Teen Talk.

Comparatively little systematic data exists concerning medical student education from the inpatient child and adolescent psychiatry venue. Training in this venue is vulnerable to pressures including increasingly reduced lengths of stay and greater emphasis on clinical productivity. An extracurricular psychosocial opportunity during evening hours may be a productive means through which to provide meaningful patient exposure, training, and mentorship to trainees. We sought to evaluate the impact upon student beliefs and attitudes through participation in an initiative titled “Story Time and Teen Talk.” Under the direct supervision of postgraduate resident physicians in psychiatry, students read fairy tales and children’s literature to children and conducted group discussions with adolescents during weekly held evening hours. Students were invited to complete a 15-item questionnaire that surveyed the impact of their participation on their beliefs and attitudes concerning general medical education and patient care, the field of psychiatry, and training in child and adolescent psychiatry. A subset of students underwent a semi-structured interview which was evaluated via grounded theory analysis to determine qualitative themes related to impact of program participation. Thirty students (N = 30) completed the survey and five students (N = 5) completed the interview. The majority of students reported strongly agreeing or agreeing that participation impacted their attitudes and beliefs about general medical education and patient care in twelve of the thirteen assayed items. Themes from qualitative analysis supported these findings. Extracurricular opportunities may be a productive venue for graduate medical education and, specifically, child and adolescent psychiatry.
SPATIAL AND TEMPORAL CLIMATOLOGY OF SNOWSTORMS IN THE DEEP SOUTH

Significant snowstorm events occurring during the winters from 1948/49 through 1989/90 are studied using a network of 100 weather stations across the southern states of Mississippi, Alabama, Georgia and South Carolina. To qualify for entry into the snowstorm inventory, at least 10 out of the 100 sites need a minimum of 25 mm (1 inch) of snowfall. A total of 69 events are identified and further categorized into four magnitudes based upon areal coverage or total snowfall amount. The storms are also classified into regional categories based upon the dominant part of the study area affected. The spatial characteristics of the snowstorms are discussed and illustrated with maps showing snowfall distributions for representative storms. Most events impact the northern portions of the study area although some very major storms fit into a Miscellaneous category with unique snowfall distributions in the southern or central parts of the Deep South. The temporal character of snowstorm frequency reveals that a very low...
The Central Asian revolt of 1916: a collapsing empire in the age of war and revolution: edited by Aminat Chokobaeva, Cloé Drieu and Alexander Morrison, Manchester, Manchester University Press, 2019, 360 pp., £80.00, ISBN: 978-1-5261-2942-0

If there's a word that sums up this new anthology of essays on the 1916 revolt in Central Asia, it's ‘depth’. This is no mishmash of think-piece placeholders to set the agenda for future substantiv...
Pulmonary Hypertension and its Association with Cardiac Transplant Outcomes: Does PA Systolic Matter?

Background Pulmonary hypertension (PH) is a common in patients with chronic heart failure (HF). For patients who progress to end stage HF and require orthotropic heart transplant (OHT), irreversible PH is a relative contraindication as it may lead to post-operative right HF. The International Society of Heart and Lung Transplant (ISHLT) recommends that transplantation be pursued in patients with a pulmonary vascular resistance (PVR) Methods This was an analysis of OHT recipients captured in the United Network for Organ Sharing (UNOS) transplant registry. We included OHT recipients with a PVR ≤ 3 Woods Units for analysis. The cohort was further categorized by PASP (PASP > 50 mmHg and PASP ≤ 50 mmHg). Primary outcome was survival. We classified survival as short term (0-5 years), Intermediate (6-10 years) and long-term (>15 years). Secondary outcome was graft failure. Baseline characteristics were compared between the two groups using the chi-squared analysis. Unadjusted associations between PASP and patient survival were determined using the Kaplan-Meier estimations and confounding was addressed using multivariable Cox proportional hazards models. Results Our study included 62,793 OHT recipients (7,187 PASP>50 mmHg, 55,606 PASP ≤50 mmHg) from 1999-2019. The PASP >50 mmHg group had a mean PASP of 60 ±8 mmHg, were older (50.9 vs 44.9 years, p= Conclusions In this large multicenter study of OHT recipients, patients with PASP>50 mmHg have similar outcomes to patients with lower PASP. OHT should be considered an option for patients with this hemodynamic derangement. Studies into factors that affect long-term outcomes is warranted.
Customer Intention to Use Facial Recognition Technology at Quick-Service Restaurants

This study aims to provide a model that examines the predictors of intention to use facial recognition technology by customers in quick-service restaurants. The proposed model combines the unified theory of acceptance and use of technology (UTAUT) and contextual constructs, such as hedonic motivations, personal innovativeness, trust, perceived privacy, and security protection. The model was tested via structural equation modeling (SEM) by using data collected from a sample of quick-service restaurant customers. The findings of the study provide a valuable theoretical contribution to academia and practical implications for the restaurant managers.
Observing inside the coronagraphic regime with nulling interferometry

Interferometry can reach high resolution not only with separated apertures, but also across a single telescope aperture. Indeed, as shown by the Palomar Fiber Nuller (PFN), cross-aperture nulling interferometry can detect companions at much smaller angular offsets from stars than coronagraphy on the same telescope can reach. In particular, the PFN was able to detect the faint secondary companion of the spectroscopic binary η Peg at roughly a third of the telescope’s diffraction beamwidth, with null depth accuracies of several 10-4, while also demonstrating the use of baseline rotation to detect companions, as originally envisioned for space-based nullers. Cross-aperture nulling observations can thus resolve separations well inside the central core of a telescope’s diffraction beam. Here we summarize the lessons learned from the PFN’s demonstration experiments, as well as from larger mid-infrared nullers, pointing toward potential performance improvements that could enable a variety of nulling-based exoplanet and dust observations interior to the coronagraphic regime on larger telescopes. Two interesting new developments are the grating nuller, in which both beam combination and phase shifting are provided by the same optical element, and the vortex fiber nuller, which straddles the coronagraphic and separated-subaperture interferometric regimes.
UVB stimulates production of enkephalins and other neuropeptides by skin-resident cells.

While studies on the ultraviolet B (UVB)-induced expression of proenkephalin (PENK) in murine regulatory T (Treg) cells with their possible role in regulation of skin homeostasis (1) are of interest, several very important issues have to be addressed to establish their significance. First, PENK is expressed and processed to the final opioid peptides including Leu- and Met-enkephalins in the resident skin cells such as keratinocytes, melanocytes, and fibroblasts, and this expression and production … [↵][1]1To whom correspondence may be addressed. Email: aslominski{at}uabmc.edu, chanderraman{at}uabmc.edu, or rslominski{at}uabmc.edu. [1]: #xref-corresp-1-1
The Market in Unmatured Tort Claims: Twenty Years Later

In 1989, Professor Robert Cooter argued for changes in the law that would facilitate the development of a market in unmatured tort claims. And yet it remains unadopted in all jurisdictions. There is a reason for this. In this paper I reexamine the proposal as to its likely intended and unintended effects. This article argues that, for such a market to work, three modifications must be made. First, the tort awards must be based on optimal-deterrence-damages rather than full-compensation damages. (The paper provides an explanation of full-compensation damages, optimal-deterrence damages, and optimal-insurance damages.) Second, potential tortfeasors must not be allowed to purchase the claims of their potential victims. Third, agreements between potential tortfeasors and the holders unmatured tort claims must be prohibited.
Novel risk factors for glucarpidase use in pediatric acute lymphoblastic leukemia: Hispanic ethnicity, age, and the ABCC4 gene

Background Carboxypeptidase G2 (CPDG2 ; glucarpidase) is a rescue drug for patients at risk for kidney injury from high-dose methotrexate (MTX). As there are no strategies for predicting patients who will require CDPG2 , we evaluated the role of demographic, clinical, and genetic factors for CPDG2 use. Procedure Cases who received CPDG2 and controls who did not were identified by chart review of acute lymphoblastic leukemia (ALL) patients who received MTX doses between 1000 and 5000 mg/m2 between 2010 and 2017. We used multivariable Bayesian logistic regression to evaluate the association of CPDG2 use with demographic and clinical variables and, on a subset of patients, with genetic ancestry and 49 single nucleotide variants previously associated with MTX toxicity. Results We identified 423 patients who received 1592 doses of MTX. Of the 18 patients who received CPDG2 , 17 (94%) were Hispanic. No patients who received 1000 or 2000 mg/m2 of MTX received CPDG2 . Hispanic ethnicity (odds ratio: 4.68; 95% compatibility interval: 1.63-15.06) and older age (1.87 [1.17-3.17]) were associated with receiving CPDG2 . Of the 177 patients in the genomic cohort, 11 received CPDG2 . Each additional G allele of rs7317112 in ABCC4 increased the odds of requiring CPDG2 (3.10 [1.12-6.75]). Six other loci (NTRK1/rs10908521, TSG1/rs9345389, STT3B/rs1353327, SCLO1B1/rs4149056, GATA3/rs3824662, ARID5B/rs10821936) demonstrated probabilities of association between 88% and 97%. Conclusion We demonstrated that demographic characteristics, including Hispanic ethnicity and age, are associated with CPDG2 use. Additionally, we provide evidence that inherited genetic variation is associated with risk of requiring CPDG2 . If validated in independent populations, this information could be leveraged to develop targeted toxicity prevention strategies for children with ALL.
Choosing the Estimand When Matching or Weighting in Observational Studies

Matching and weighting methods for observational studies require the choice of an estimand, the causal effect with reference to a specific target population. Commonly used estimands include the average treatment effect in the treated (ATT), the average treatment effect in the untreated (ATU), the average treatment effect in the population (ATE), and the average treatment effect in the overlap (i.e., equipoise population; ATO). Each estimand has its own assumptions, interpretation, and statistical methods that can be used to estimate it. This article provides guidance on selecting and interpreting an estimand to help medical researchers correctly implement statistical methods used to estimate causal effects in observational studies and to help audiences correctly interpret the results and limitations of these studies. The interpretations of the estimands resulting from regression and instrumental variable analyses are also discussed. Choosing an estimand carefully is essential for making valid inferences from the analysis of observational data and ensuring results are replicable and useful for practitioners.
Applying Gaussian Mixture Models to Detect Fish from Airborne LiDAR Measurements

Airborne LiDAR has been used to monitor marine life and ecological health. However, manually searching the data for important features is an inefficient process. Here, we use Gaussian Mixture Models and supervised classification techniques to automatically detect fish in airborne LiDAR data.
Survey, Automated Detection, and Spatial Distribution Analysis of Cairn Tombs in Ancient Southern Arabia

Small circular cairn tombs found across southern Arabia offer an ­intriguing window into the movements and mortuary practices of ancient hinterland peoples. This chapter briefly reports preliminary results of archaeological survey, automated detection efforts and spatial distribution analysis for such tombs across the Southern Jol area of Hadramawt Governate Yemen. The most detailed level of survey recording was conducted for 394 tombs, an automated detection algorithm (to shortly be reported in far greater detail elsewhere) yielded highly promising results, and GIS analyses indicate associations between tombs and water-rich areas.
Hormones and receptors in endometrial cancer

The uterine endometrium is exquisitely sensitive to hormones. These hormones, acting through their cognate receptors, tightly regulate growth, development, and remodeling of reproductive tissues as well as the cyclic changes that occur during the menstrual cycle. In the endometrium, estrogen receptor (ER) and progesterone receptor (PR) are induced in the first half of the cycle and down-regulated in the luteal phase. ERs are expressed in increasing concentrations as the proliferative phase of the cycle progresses. At ovulation, ERs are down-regulated in response to progesterone production from the ovary. PRs are also induced in increasing concentrations during the proliferative phase, in part due to rising estradiol levels that induce PRs through ERs. During the secretory phase of the menstrual cycle, ERs and PRs are gradually down-regulated in the glandular epithelium, but PRs are still expressed in the stroma where progesterone is critical for ongoing proliferation and the secretory response. Androgen receptors (ARs) are in general induced by estrogen during the proliferative phase of the cycle and down-regulated by testosterone in the late secretory phase. Progesterone has also been implicated in the induction of AR in the endometrium, most likely when it is combined with estrogen. Androgen also inhibits the effects of estrogen, limiting proliferation in the epithelium and the stroma.
Calculating Medicaid’s Taxpayer Burden for FY 2008, from a National and State Perspective

What the nation spends on Medicaid/CHIP is very different than what Americans pay for Medicaid/CHIP. Using FY2008 data on state Medicaid/CHIP spending this paper estimates a proxy of the actual costs borne by the typical taxpayer by accounting for income and tax distribution across the states. The paper includes estimates of the cost of the federal-share of Medicaid by income level as well as by state (and region), controlling for the share of federal general spending financed by individual income taxes; as well as the cost of the state-share by state controlling for the share of state revenues collected from in-state residents. It concludes that relative to how much of total Medicaid spending that state residents directly underwrite in terms of the state and federal taxes they pay, state residents - with the exception of Colorado - get a high return on their redistributive dollars. The nation’s Medicaid/CHIP program costs the residents of the average state an equivalent of 58 percent of the Medicaid/CHIP spending in the state. The implications of these depressed costs on efficiency of public spending and accountability are given (preliminary) consideration.
Was the IMF's Imposition of Economic Regime Change Justified? A Critique of the IMF's Economic and Political Role in Korea During and After the Crisis

As late as October 1997 the IMF declared that the Korean economy was experiencing a temporary liquidity squeeze, not a solvency problem. Yet in December 1997 Deputy Managing Director Stanley Fischer declared that Korea suffered from a systemic “breakdown of economic relations” so complete that only radical economic restructuring could restore prosperity. The IMF attached what it called “extreme structural conditionality” to its loan agreements with Korea, demanding a complete and rapid transition from Korea’s traditional East Asian economic model to a globally integrated neoliberal model. We subject the IMF’s assertion that the allocative efficiency of the Korean economy had collapsed by 1997 to a number of empirical tests, including time series and cross-section analyses of capital productivity and corporate profitability, and firm and industry level econometric tests of the proposition that investment spending was excessive and misallocated in the pre-crisis period. This evidence does not support the IMF’s systemic breakdown claim. We conclude that the IMF’s imposition of “extreme structural conditionality” on Korea is best understood as an illegitimate and antidemocratic exercise of power designed to meet the needs of the IMF’s key constituents rather than those of the majority of Korea’s people.
Power reduction in wireless receivers through multistage digital filtering and quantization

The number of bits required to accurately represent a received signal in a wireless system changes as the out-of-band interference is removed by an IIR digital filter, if the filtering is done in stages, such as second-order sections. Taking advantage of this fact can reduce the size of the datapath in a VLSI realization of a digital filter, and hence power and area can be saved without decreasing performance. An effective algorithm for computing this reduced number of bits to use for quantization after each stage is derived, and a scheme for optimally ordering the second-order sections is presented, power savings range from 33% to 50%, depending on the amount of out-of-band interference.
Filamentous capsulated streptococci from the human respiratory tract. II. Antigenic structure of provisional capsular types 89 and 83-89.

Two immunologically distinct polysaccharides have been isolated from the filamentous alpha-hemolytic streptococcus of provisional capsular type 89, recovered from the human respiratory tract. Chemical analyses indicate that the capsular polysaccharide consists of glucose, galactose, and a small amount of rhamnose, whereas the cell wall-associated polymer contains galactosamine, glucosamine, glucose, and phosphorus. Immunological studies suggest that the capsular polysaccharide is type specific and that the cell wall-associated carbohydrate, which cross-reacts with the C 8 , or cell wall-like capsular polysaccharide of pneumococcus, may be group specific. A noncapsulated variant of the prototypic streptococcus of provisional type 89 was shown to possess the same cell wall-associated carbohydrate as the strain from which it was derived, but it proved to be poorly antigenic in rabbits. A filamentous capsulated streptococcus reacting with antisera to filamentous streptococci of both provisional capsular types 83 and 89 has been found to produce two capsular polysaccharides, each of which reacts with antibody to one of the aforementioned unitypic strains and represents an unusual binary capsulated streptococcus. Images
ViP: A User-Centric View-Based Annotation Framework for Scientific Data

Annotations play an increasingly crucial role in scientific exploration and discovery, as the amount of data and the level of collaboration among scientists increase. In this paper, we introduce ViP, a user-centric, view-based annotation framework that promotes annotations as first-class citizens. ViP introduces novel ways of propagating annotations, empowering users to express their preferences over the time and network semantics of annotations. To efficiently support such novel functionality, ViP utilizes database views and introduces new caching techniques. Through an extensive experimental study on a real system, we show that ViP can seamlessly introduce new annotation propagation semantics while significantly improving the performance over the current state of the art.
High-resolution wrist-worn overnight oximetry has high positive predictive value for obstructive sleep apnea in a sleep study referral population.

Background Reducing the need for diagnostic sleep studies for obstructive sleep apnea (OSA) would reduce direct and opportunity costs while expediting time to treatment for this common and morbid disorder. We sought to determine if an established sleep apnea screening questionnaire (STOP-BANG) and wrist-worn overnight oximetry data could provide high positive predictive value for the presence of OSA.
The Evolution of Mutator Genes in Bacterial Populations: The Roles of Environmental Change and Timing

Recent studies have found high frequencies of bacteria with increased genomic rates of mutation in both clinical and laboratory populations. These observations may seem surprising in light of earlier experimental and theoretical studies. Mutator genes (genes that elevate the genomic mutation rate) are likely to induce deleterious mutations and thus suffer an indirect selective disadvantage; at the same time, bacteria carrying them can increase in frequency only by generating beneficial mutations at other loci. When clones carrying mutator genes are rare, however, these beneficial mutations are far more likely to arise in members of the much larger nonmutator population. How then can mutators become prevalent? To address this question, we develop a model of the population dynamics of bacteria confronted with ever-changing environments. Using analytical and simulation procedures, we explore the process by which initially rare mutator alleles can rise in frequency. We demonstrate that subsequent to a shift in environmental conditions, there will be relatively long periods of time during which the mutator subpopulation can produce a beneficial mutation before the ancestral subpopulations are eliminated. If the beneficial mutation arises early enough, the overall frequency of mutators will climb to a point higher than when the process began. The probability of producing a subsequent beneficial mutation will then also increase. In this manner, mutators can increase in frequency over successive selective sweeps. We discuss the implications and predictions of these theoretical results in relation to antibiotic resistance and the evolution of mutation rates.
Technology, Multimedia, and Qualitative Research in Education

AbstractThe role of technology and multimedia in enhancing research is illustrated through the use of examples from more qualitative approaches to inquiry. The author makes reference to key characteristics of qualitative techniques and emphasizes implications for data collection, data analysis, and the presentation of findings. Articles appearing in the online issue of JRCE and reprinted in 29(4), 30(1), and 30(2), serve as illustrations of both the characteristics of qualitative research and examples of the impact of technology and multimedia on the research process.
Peeling stress analyzed for resistance to delamination - application to multiple thin films on a thick substrate

Timoshenko examined axial stresses and bending in bimetal thermostats; he did not examine interfacial stresses. Research has since proceeded on two fronts - approximate analyses of interfacial peeling and shear in a bimaterial beam or plate, and examination of axial stress and warpage in a multilayer beam. This paper draws on an exact partial solution for peeling at all interfaces in a multilayer beam, and presents a case study of multiple layers on silicon. It is a significant advantage to have a negative peeling stress at the free edge in order to prevent delamination from starting. The sign and magnitude of the peeling moment in a bimaterial beam or plate indicate the sign of the peeling stress at the free edge and a relative measure of its magnitude. These immediately show whether a resistance or a propensity to delamination exists at the free edge of the interface. This paper describes an exact solution for the peeling moments at each interface in a multilayer beam; it also offers a new insight into how peeling stresses arise. The method gives values at all interfaces, irrespective of the temperatures of bonding at each. It is equally applicable to layers of similar thicknesses, and to thin films on a thick substrate. An analysis is made of a silicon substrate with three thin layers applied at different temperatures. The peeling moment and shear force in each interface is determined. A discussion is included on the effects of changes to material properties and thicknesses; this analysis found that for all reasonable variations in layer thickness and properties the interfaces on the Silicon-on-Insulator wafer are inherently resistant to the start of delamination at room temperature.
Meal Feeding Alters Translational Control of Gene Expression in Rat Liver

Meal feeding after a period of food deprivation results in a subsequent increase in the protein and RNA content of the liver. To gain insight into the mechanisms involved in the response to food intake, changes in the association of selected mRNAs with polysomes were examined. On the day of the study, rat livers were collected at 0, 15, 60, and 180 min after the start of feeding and analyzed for biomarkers of the translational control of protein synthesis. Protein synthesis was increased within 60 min and was sustained for 180 min. Assembly of the active eukaryotic initiation factor (eIF) 4F complex was elevated within 15 min, as indicated by the relative association of eIF4E . eIF4G, but returned to the basal value within 180 min. Phosphorylation of the ribosomal protein (rp) S6 kinase S6K1 and its substrate rpS6 was increased within 15 min and was sustained for at least 180 min. Both eIF4F assembly and activation of S6K1 have been linked to upregulated translation of a subset of mRNAs. To identify translationally regulated mRNAs, polysomal (i.e., actively translated) and nonpolysomal (nontranslated) fractions were isolated and subjected to microarray analysis. The mRNAs encoding 78 proteins, including 42 proteins involved in protein synthesis, exhibited increased abundance in polysomes in response to feeding. Overall, the results demonstrate that protein synthesis as well as ribosomal protein mRNA translation undergo rapid and sustained stimulation in the liver after meal feeding and thus contribute to the previously observed increases in protein and RNA content.
Torsion on theta divisors of hyperelliptic Fermat Jacobians

We generalize a result of Anderson by showing that torsion points of certain orders cannot lie on a theta divisor in the Jacobians of hyperelliptic images of Fermat curves. The proofs utilize the explicit geometry of hyperelliptic Jacobians and their formal groups at the origin.
A PROTEIN SWITCH SENSING SYSTEM FOR THE QUANTIFICATION OF SULFATE

Protein engineering has generated versatile methods and technologies that have been instrumental in advancements in the fields of sensing, therapeutics, and diagnostics. Herein, we demonstrate the employment of rational design to engineer a unique bioluminescence-based protein switch. A fusion protein switch combines two totally unrelated proteins, with distinct characteristics, in a manner such that the function of one protein is dependent on another. Herein we report a protein switch sensing system by insertion of the sulfate-binding protein (SBP) into the structure of the photoprotein aequorin (AEQ). In the presence of sulfate, SBP undergoes a conformational change bringing the two segments of AEQ together, "turning on" bioluminescence in a dose-dependent fashion, thus allowing quantitative detection of sulfate. A calibration plot was obtained by correlating the amount of bioluminescence generated with the concentration of sulfate present. The switch demonstrated selectivity and reproducibility, and a detection limit of 1.6×10(-4)M for sulfate. Moreover, the sensing system was validated by performing sulfate detection in clinical and environmental samples, such as, serum, urine, and tap water. The detection limits and working ranges in all three samples fall within the average normal/recommended sulfate levels in the respective matrices.
Tranquility and preference revisited

Abstract Independent groups rated 66 color slides of natural settings for the target variables tranquility and preference and for five descriptor variables. There were an equal number of settings from each of three categories: field/forest, deserts, and large waterscapes. Tranquility and preference ratings were substantially and positively correlated in all setting categories. Still, it was possible to distinguish the two constructs. Mean tranquility and preference ratings differed in all three setting categories, with tranquility rated higher in the field/forest and large-waterscapes categories and preference rated higher for deserts. The two target variables also differed in the pattern of their relationships with the descriptor variables. Both mystery and focus tended to be positive predictors of preference but not of tranquility in the field/forest category. Unstructured openness was a negative predictor of preference but not of tranquility in the field/forest category. Surface calmness was a stronger negative predictor of preference than of tranquility for deserts.
Sociological Perspectives on Imposed School Dress Codes: Consumption as Attempted Suppression of Class and Group Symbolism:

As a reaction to crime and gang violence, public schools in U.S. inner-city areas are increasingly implementing dress codes. Dress codes restrict students use of clothing as an element of contempor...
Impact of the cost of prescription drugs on clinical outcomes in indigent patients with heart disease.

Study Objective. To measure the impact that economic relief for prescription drugs to indigent patients with cardiovascular disease has on indicators of disease control. Design. Prospective cohort study. Setting. University inner-city outpatient clinic. Patients. One hundred sixty-three indigent patients with heart disease who were uninsured or whose insurance plan did not provide prescription drug coverage and who had baseline data. Intervention. Patients were assisted in obtaining prescription drugs, free of charge, in an attempt to improve adherence to their drug regimens. Measurements and Main Results. The primary end point was to determine if cardiovascular outcome measures (i.e., international normalized ratio [INR], blood pressure, low-density lipoprotein [LDL] cholesterol, and hospitalizations) and drug adherence improved in all patients after 6 months of prescription assistance compared with a 6-month baseline period. In patients receiving warfarin, mean INR increased from 2.44 ± 0.64 at baseline to 2.61 ± 0.53 at 6 months (p<0.05). In patients with hypertension, mean blood pressure decreased from 138 ± 20/80 ± 11 mm Hg at baseline to 138 ± 19/78 ± 12 mm Hg at 6 months (p<0.05 for diastolic blood pressure only). The mean LDL level for patients on lipid-lowering drugs significantly decreased from 126 ± 39 mg/dl at baseline to 108 ± 38 mg/dl at 6 months (p<0.001). For each disease measure, the improved disease control seen at 6 months persisted throughout 24 months of follow-up. Hospitalizations for the entire cohort decreased from 85 at baseline to 49 at 6 months. Patient drug adherence improved from 48.5% at baseline to 72.7% at 6 months (p<0.001). Conclusions. Drug adherence and clinical outcomes improved, and the number of hospitalizations declined when cardiovascular drugs were obtained for patients who could not afford to pay for them. Health care insurance plans that do not provide coverage for cardiovascular prescription drugs may be more costly secondary to poor disease control and increased hospitalizations.
Stereotaxic coordinates of the brain of the golden hamster (Mesocricetus auratus).

During the course of investigating another problem, the writer placed lesions in neocortex and limbic system structures in 123 female Golden Hamsters weighing 90 to 110 gm. The stereotaxic coordinates for the hamster brain developed by Smith and Bodemer (1963) were used previously on 20 Ss both male and female and adjusted where necessary for these animals. The anterior-posterior coordinates of their atlas were not completely applicable to these Ss for accurately locating the septa1 area, cingulate gyrus, and the amygdala. However, once a structure or area was located, there was only a very small variation in the A-P dimension in animals of the same weight category (90, 100 or 110 gm.) and the intra-brain spatial relations which they report were very accurate. The work of the writer and of Smith and Bodemer was done on two different Stellartype stereotaxic instruments which were constructed at the same time in the University of Washington School of Medicine machine shop according to the design of Stellar and Krause (1954). A few minor modifications were incorporated but there were no major differences between the instrument Stellar and Krause describe and these two (Smith, personal communication, 1968). In addition to using an almost identical instrument, Ss were aligned as described by Smith and Bodemer. Their perfusion and frozen section technique was followed. The same histologist who prepared their work also sectioned and mounted many of the author's animals. The writer concludes that the work of Smith and Bodemer is highly reliable because once a structure is located other areas can be found following their insuuctions; however, their initial anterior-posterior directions may not bring E directly to the desired position. Their A-P locations can be used but may result in an anterior error of 2 mm. or more, depending on S's weight. A second conclusion is that this A-P difference is probably a constant error introduced by minor variations in the construction of the two stereotaxic instruments. Confirmation of the true distances of areas from ear bat zero for animals of various weights will have to come from future studies using a number of different instru
The aggregate update problem in functional programming systems

We discuss the problem of efficiently implementing aggregates (contiguous data structures) such as arrays in functional programming systems. Simple changes to an aggregate conceptually involve making a new copy of the aggregate differing only in the changed component, but such copying can be expensive. We present both static and dynamic techniques for avoiding this copying, and argue that they allow one to program functionally using aggregates, without loss of efficiency over conventional programs.1
Intraguild predation with spatially structured interactions

Abstract Consumer–resource interactions with intraguild predation (IGP) were studied in a spatial setting (i.e., predators catch prey and individuals reproduce within local neighborhoods only). Pair approximation (a method for deriving ordinary differential equations that approximate the dynamics of a community that interacts in a lattice environment) was used to study the effect of spatially structured species interactions. An individual-based computer simulation was used to extend the study to a case with spatially variable resource densities. The qualitative results of the pair approximation model were similar to those of the corresponding non-spatial model. However, the spatial model predicted coex((istence over a wider range of parameters than the non-spatial model when intraguild prey are nutritionally valuable to intraguild predators. Spatially heterogeneous resource distributions and spatially structured interaction could overturn the qualitative predictions of non-spatial models.
Seismic performance of self-centering structural walls incorporating energy dissipators

This paper presents elements of seismic design for jointed precast cantilever wall units designed to rock about their foundation. Gravity loading and prestressed unbonded tendons provide the restoring force in these walls. Lateral displacements eventually result in a separation gap forming only at the wall-foundation beam connection. The gap reduces the wall stiffness and results in nonlinear response. Design of these walls is made with the explicit objective of ensuring a self-centering response. That is, the wall returns to its pre-earthquake position upon unloading from a large displacement excursion. The integrity of the walls is maintained because no plastic hinges form and there are no residual postearthquake displacements. Energy dissipators, in the way of longitudinal mild steel reinforcement crossing the joint between the walls and the foundation, are incorporated into these walls to add significant energy dissipation capacity while preserving the self-centering response. This paper also describe...
Heat capacities and related thermal properties of DyNi5, HoNi5 and ErNi5 between 5 and 300 K☆

Abstract Heat capacity data and calculated thermodynamic functions are presented for DyNi 5 , HoNi 5 and ErNi 5 . λ-type thermal anomalies are noted at 12.0 K (DyNi 5 ), 4.1 K (HoNi 5 ) and 8.0 K (ErNi 5 ). Schottky-type anomalies are observed at higher temperatures. The λ and Schottky anomalies are ascribed to the destruction of ferromagnetic order and to crystal field excitation, respectively. A deficiency of magnetic entropy, compared to R ln(2 J + 1), is noted corresponding roughly to R ln2. This suggests that the ground state in the ordered materials is a doublet. ErNi 5 is analyzed using a Hamiltonian containing terms representing the crystal field and magnetic interactions. The analysis shows that a doublet ground state can result with reasonable values of the crystal field parameters. The parameters are shown to be consistent with the heat capacity behavior of ErNi 5 . Ordering temperatures are not proportional to the de Gennes function.