cssi/SciSciGPT-SciSciNet huggingface dataset:
The Impact of Practice on Pedagogy: Reflections of Novice Evaluation Teachers

In this practice note two novice evaluation teachers share their findings from research conducted with students who were enrolled in a theory and practicum course in evaluation. The study focused on understanding how and in what ways students navigate between the world of theory and the world of practice. The find-ings from this study subsequently led to a re-envisioning of the course offerings to provide a more nuanced transition between two dichotomized conceptualizations of evaluation (theory and practice), revised syllabi, and the addition of a third course. The implications of this research (and subsequent pedagogical revisions) raise im-portant issues for evaluation teachers and practitioners, as we continue to debate the relationship between theory and practice in evaluation. Dans cette note de pratique, deux nouveaux professeurs d’evaluation font part des resultats d’une etude effectuee aupres d’etudiants inscrits a un cours theo-rique et a un stage en evaluation. L’etude visait a comprendre comment et de quelle facon les etudiants font la transition entre la theorie et la pratique. Les resultats de cette l’etude ont par la suite mene a une refonte de cours pour faciliter la transition entre des conceptualisations dichotomisees de l’evaluation (theorie et pratique), une revision du curriculum et l’ajout d’un troisieme cours. Cette recherche (les revisions pedagogiques qu’elle a entrainees) souleve des questions importantes pour les profes-seurs et les praticiens de l’evaluation, alors que se poursuit le debat sur le lien entre la theorie et la pratique en evaluation.
Monodisperse particle-laden exchange flows in a vertical duct

We study buoyancy-driven exchange flow of two mixtures in a vertical narrow duct (two-dimensional channel as well as pipe) theoretically. While the light mixture is assumed always to be a pure fluid, the heavy mixture can be selected as either a pure or a particle-laden fluid. A small width-to-length ratio considered for the duct ( ) has been used as the perturbation parameter in developing a lubrication model (negligible inertia). In particular, we have adopted the methodology of Zhou et al. (Phys. Rev. Lett., vol. 94, 2005, 117803) for free-surface particle-laden film flows and extended it to a lock exchange system in confined geometry under the Boussinesq approximation. The resulting model is in the form of the classical Riemann problem and has been solved numerically using a robust total variation diminishing finite difference scheme. Both pure and particle-laden cases are investigated in detail. It is observed that the interface between the two fluids takes a self-similar shape at long times. In the case that both heavy and light fluids are pure, the dynamics of the flow is governed by two dimensionless quantities, namely the Reynolds number, , and the viscosity ratio, , of the light and heavy fluids. The interpenetration of the heavy and light layers increases with but decreases with . Also, the heights of the heavy and light fronts change with but remain unchanged with . In the case of the particle-laden flow, however, four additional dimensionless parameters emerge, namely the initial volume fraction of particles, , the ratio of particle diameter to duct width, , and the density ratios of particles to carrying fluid, , and of light fluid to carrying fluid, . The effect of these parameters on the dynamics of the flow has been quantified through a systematic approach. In the presence of solid particles, the interface between the heavy and light layers becomes more curved compared to the case of pure fluids. This modification occurs due to the change of heavy mixture viscosity alongside the duct. Novel particle-rich zones are further discovered in the vicinity of the advancing heavy and light fronts. These zones are associated with different transport rates of the fluid and solid particles. The degree of particle enrichment remains the same with , is enhanced by , and , and is slightly diminished with and . On the other hand, the stretched exchange zone between the heavy and light fronts grows with , and , but decays with , and .
The Roles of Chaperones in RNA Folding

Because of its limited structural diversity, RNA has a strong tendency to misfold, and the stability of local structure often causes misfolded conformations to be long-lived on the biological time scale. The effects of RNA misfolding are dealt with in vivo by chaperones. Some of these chaperones function by interacting strongly with unstructured RNA and do not depend on a source of energy for their activities, while a second group couples unfavorable RNA rearrangements to the favorable hydrolysis of ATP. This latter group is made up of RNA helicase ­proteins, with the largest group being the DEAD-box proteins. While some ATP-dependent RNA chaperone proteins are evolved to function on specific substrate RNAs or RNA–protein complexes, others function as general chaperones by interacting ­functionally with a broad range of RNA structures. Experimental studies using diverse approaches have begun to ­elucidate the mechanisms of RNA ­chaperones in rearranging RNAs. In this chapter, we describe the mechanistic ­features that are thought to underlie chaperone activity, with a focus on group I and group II introns as experimental systems.
Cross-Cultural Use of Measurements

In recent years, health-related quality of life (HRQoL) measures are rapidly becoming standard tools for evaluating clinical effectiveness in patients and for assessing health status in populations (Guillein, Bombardier, & Beaton, 1993; McDowell & Newell, 1987). As more people live longer with chronic diseases (Croog & Levine, 1989; Patrick & Erickson, 1993), the goal of health care is no longer focused on survival or curing the disease, but on optimizing individual’s functional health and well-being (Ferguson & Cherniack, 1993). This shift in focus of health care suggests that health assessment will depend more heavily on an individual’s participation, that is, his or her perception and accurate reporting of symptoms, functioning, and disabilities (Campen, Sixma, Friele, Kerssens, & Peters, 1995; Geigle & Jones, 1990; Till, Osoba, Oater, & Young 1994).
Interview by Kate Mullen — Math, Science & Fantasy

[Interview on philosophy, Annandale-on-Hudson, March 2001. Kate Mullen is an undergraduate at Bard College, and she published the bulk of this interview in the Bard Free Press, the student newspaper.]
Legacies of Positivism in the Philosophy of Science

It has become common to use “positivist” and “positivism” as words of opprobrium. Positivists are rigid, unimaginative, committed to an unrealistic separation of fact and value. So understood, the epithet may fit some scientists, both past and present. And one might justly think of positivism’s legacy as a bad philosophical hangover. But this understanding mischaracterizes the original positivists. First I sketch what the original positivists were about and indicate both strengths and shortcomings of the views they advocated. Then, I suggest an alternative approach to thinking about the nature of knowledge in science that retains some of positivism’s original aspirations without the overreach that was its downfall.
Investigation of Hardness of Ternary Borides of the YCrB4, Y2ReB6, Y3ReB7, and YMo3B7 Structural Types

The metal borides: YReB4, YCrB4 (YCrB4 structural type), Y2ReB6, Sc2ReB6 (Y2ReB6), Y3ReB7, Y3MoB7, and Y3WB7 (Y3ReB7), and YMo3B7 (YMo3B7) structural types, and their solid-solutions: YRe1–xCrxB4, Y1–xScxCrB4, Y2–2xSc2xReB6, Y2Re1–xCrxB6, and YMo1–xWxB7 were analyzed using powder X-ray diffraction and energy-dispersive X-ray spectroscopy, and studied for their mechanical properties. These metal borides possess unique crystal structures, not found in any other type of borides: alternating metal and boron layers with boron being arranged in 5-, 6-, and 7-member rings (YCrB4, Y2ReB6), corrugated cages of 5- and 13-member boron rings (Y3ReB7), as well as stacked layers of ribbons of hexagonal boron atoms 6 rings wide (YMo3B7). Although none of these borides in pure form possess high hardness, their solid solutions are superhard (Vickers hardness above 40 GPa): 42.48 ± 2.13 GPa for an alloy with a nominal composition of (YRe0.5Cr0.5):4B, 42.02 ± 2.05 GPa for (Y0.5Sc0.5Cr):4B and 41.33 ± 2.18 GPa for (YScRe):6B...
TCT-406 Elevated uric acid is associated with increased lesion calcification and increased mortality in women undergoing percutaneous coronary intervention

Serum uric acid is a marker of oxidative stress, and may serve as a marker of cardiovascular events and outcomes. There is limited data on the role of uric acid level in secondary prevention among women. We aimed to determine whether elevated serum uric acid levels were predictive of worse outcomes
Evaluating the Validity of the DSM-5 Alcohol Use Disorder Diagnostic Criteria in a Sample of Treatment-seeking Native Americans.

Objective Despite high rates of alcohol use disorder (AUD) and alcohol-induced deaths among Native Americans, there has been limited study of the construct validity of the AUD diagnostic criteria. The purpose of the current study was to examine the validity of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) AUD criteria in a treatment-seeking group of Native Americans. Methods As part of a larger study, 79 Native Americans concerned about their alcohol or drug use were recruited from a substance use treatment agency located on a reservation in the southwestern United States. Participants were administered the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders (SCID for DSM-IV-TR) reworded to assess 11 DSM-5 criteria for AUD. Confirmatory factor analysis (CFA) was used to test the validity of the AUD diagnostic criteria, and item response theory (IRT) was used to examine the item characteristics of the AUD diagnostic criteria in this Native American sample. Results CFA indicated that a 1-factor model of the 11 items provided a good fit of the data. IRT parameter estimates suggested that "withdrawal," "social/interpersonal problems," and "activities given up to use" had the highest magnitude of discrimination. "Much time spent using" and "activities given up to use" were associated with the greatest severity. Conclusions The current study provided support for the validity of the AUD DSM-5 criteria and a unidimensional latent construct of AUD in this sample of treatment-seeking Native Americans. IRT analyses replicate findings from previous studies. To our knowledge, this is the first study to examine the validity of the DSM-5 AUD criteria in a treatment-seeking sample of Native Americans. Continued research in other Native American samples is needed.
RURAL-URBAN DIFFERENCES IN SOCIAL ISOLATION AND ITS RELATIONSHIP TO HEALTH

Research on geographic differences in social isolation and its relationship with health is limited. Using data from Wave 2 of the National Social Life, Health, and Aging Project (n=3,377, mean age=72.4), we compared differences by rurality (urban vs. rural) in measures of reported social support, social relationships, and loneliness. We also conducted stratified ordered logistic regression models to assess how the association between isolation and self-rated health (1=poor; 5=excellent) differs by rurality. Overall, rural older adults were more likely than urban older adults to say that they could rely on family and friends, and rural residents reported larger numbers of close friends and relatives. There were no differences by rurality in loneliness, with all respondents scoring an average of 3 out of 9 on the loneliness scale. In stratified models, scoring higher on the loneliness scale was associated with poorer health for both urban and rural older adults (adjusted odds ratio [AOR]: 0.88, p<0.001 and 0.92, p<0.05, respectively). In contrast, being able to rely on family members was associated with better health (AOR: 1.46, p<0.05) for urban older adults, whereas having more friends was associated with better health for rural older adults (AOR: 1.19, p<0.05). As social isolation and loneliness continue to gain recognition as urgent population health issues, there is a critical need for targeted information on the prevalence and risk factors for social isolation and associated poorer health by geography in order to design targeted, effective interventions; this study adds useful information with which to do so.
On Not Being Able to Dance: The Interring

What makes it hard to dance? Twentieth-century phenomenologists drew attention to the importance of the lived body, and dance is the art form for which the lived body is literally central. Why then isn’t dance the easiest art form to engage in? Phenomenologists are drawn to situations where a phenomenon breaks down, which can open insights into the phenomenon itself. Here the phenomenon is the ability to dance where one might normally expect to. This paper invokes Marion Milner’s book On Not Being Able to Paint (from which the title is borrowed). It discusses views of David Kleinberg-Levin, Maxine Sheets-Johnstone, Iris Young, and others. Parallel to Heidegger’s notion of the Enframing, what causes the disappearing dimensions of animate form is the Interring.
Short-Term Changes in Cardiac Function in Osteosarcoma Patients Receiving Anthracyclines.

Studies of cardiac function in adolescent and young adult survivors have been performed at least a decade after anthracycline exposure, with little knowledge of short-term changes in cardiac functi...
Edge Computing: Scaling resources within multiple administrative domains

Creating edge computing infrastructures and applications encompasses quite a breadth of systems research. Let’s take a look at the academic view of edge computing and a sample of existing research that will be relevant in the coming years.
Determining the utility of methicillin-resistant Staphylococcus aureus nares screening in antimicrobial stewardship.

Background Treatment of suspected methicillin-resistant Staphylococcus aureus (MRSA) is a cornerstone of many antibiotic regimens; however, there is associated toxicity. The Department of Veterans Affairs (VA) hospitals screen each patient for MRSA nares colonization on admission and transfer. The objective was to determine the negative predictive value (NPV) of MRSA screening in the determination of subsequent positive clinical culture for MRSA. High NPVs with MRSA nares screening may be used as a stewardship tool. Methods This was a retrospective cohort study across VA medical centers nationwide from 1 January 2007 to 1 January 2018. Data from patients with MRSA nares screening were obtained from the VA Corporate Data Warehouse. Subsequent clinical cultures within 7 days of the nares swab were evaluated for the presence of MRSA. Sensitivity, specificity, positive predictive values, and NPVs were calculated for the entire cohort as well as subgroups for specific culture sites. Results This cohort yielded 561 325 clinical cultures from a variety of anatomical sites. The sensitivity and specificity for positive MRSA clinical culture were 67.4% and 81.2%, respectively. The NPV of MRSA nares screening for ruling out MRSA infection was 96.5%. The NPV for bloodstream infections was 96.5%, for intraabdominal cultures it was 98.6%, for respiratory cultures it was 96.1%, for wound cultures it was 93.1%, and for cultures from the urinary system it was 99.2%. Conclusion Given the high NPVs, MRSA nares screening may be a powerful stewardship tool for deescalation and avoidance of empirical anti-MRSA therapy.
Who cares about open badges? An examination of principals’ perceptions of the usefulness of teacher open badges in the United States

In this article, we examined school leaders’ perceptions of open badges for teacher candidates. We emailed one of two forms of a survey to principals and assistant principals in five school distric...
‘The rest of the time I would just stand there and look stupid’: access in integrated physical education among adults with visual impairments

In recent years, research examining the perspectives of individuals with visual impairments toward the inclusiveness of their experiences in physical education has revealed that feelings associated...
A comparison of risk factors for osteo- and rheumatoid arthritis using NHANES data.

Abstract Osteoarthritis and rheumatoid arthritis are both diseases of joints, but they have very different etiologies. Osteoarthritis is a disease assumed to result from wear and tear over time, whereas rheumatoid arthritis is an autoimmune disease where the body’s immune system attacks joint tissues. Using NHANES data (1999–2015), we have compared the influence of age, sex, ethnicity, body mass index and smoking on these two very different forms of arthritis. Incidence of both increases with age and are more frequent in females than males. There is little apparent difference between osteoarthritis and rheumatoid arthritis in women of normal as comparted to overweight, but both are more frequent in obese women, especially those over the age of 60. While osteoarthritis is more frequent in whites, blacks have more rheumatoid arthritis, and Hispanics show an intermediate prevalence. Smoking significantly increased the incidence of both osteoarthritis and rheumatoid arthritis in women, but increased prevalence of only RA in men. There was no effect of smoking on OA prevalence in males. It is remarkable that two diseases of joints, which have quite different causes, should have so many commonalities. The differences that exist appear to be due to a combination of inflammatory markers and access to health care.
Maxillofacial Bone Grafting Materials: 2021 Update.

For successful outcomes in bone grafting, it is important to have a clear and detailed understanding of the fundamentals and basics in regenerative science. This article summarize the grafting materials and growth factors that are now in use to provide an improved understanding of the properties of each material and indications for subsequent use. The article gives an overview of the fundamentals of bone healing, including the physiology of regeneration. It is hoped that clinicians can make improved decisions that are based in literature when considering treatment options for restoring patients' functional dentition.
XPS characterization of Al2O3/ZnO ultrathin films grown by atomic layer deposition

The near-surface compositional properties of double-layer Al2O3/ZnO ultrathin films, grown on the n-type GaAs substrate using the atomic layer deposition (ALD) technique, are analyzed by means of high-resolution x-ray photoelectron spectroscopy (XPS). This structure has been used as the dielectric or the passivation layer in microelectronic devices, such as metal-oxide-semiconductor (MOS) capacitors, field-effect transistors, and Schottky junctions. The XPS spectra of double-layer Al2O3/ZnO thin films were obtained using monochromatic Al kα monochromatic radiation at 1486.6 eV and included an overall survey scan, in addition to the high-resolution spectra of Zn 2p, Al 2p, O 1s, Ga 2p, and As 3d.
Enhanced Recovery After Cesarean: Current and Emerging Trends.

What are the latest enhanced recovery elements for cesarean delivery? Enhanced recovery after cesarean delivery (ERAC) provides an evidenced-based system to improve maternal outcomes, functional recovery, maternal-infant bonding, and patient experience. Postsurgical recovery has evolved from a one-dimensional pain score to a holistic multidimensional approach emphasizing faster functional recovery. ERAC involves multidisciplinary efforts of the anesthesiologist, obstetrician, nursing, hospital, and patient. Components of ERAC include preoperative patient education, limited fasting, carbohydrate load, limiting opioids intra- and postoperatively, using scheduled non-opioid analgesics and supplementing with advanced therapies for women at higher risk for pain. ERAC protocols reduce opioid consumption, reduce length of stay, and improve maternal and neonatal outcomes. Implementing ERAC standardized care will likely be the most important change you can make in your practice to improve outcomes, improve quality care, help address racial disparities, and minimize opioid exposure and potential for addiction.
The Swiss Re Tower: Analysis of a Seminal Case

The Swiss Re Tower, designed as the headquarters of the Swiss Reinsurance Company, is situated at the historic core and financial district of the City of London. Designed by the architect Foster and Partners, it is one of the most distinguished and controversial office skyscrapers in London. Officially named “30 St Mary Axe,” and popularly called the gherkin, the Swiss Re Tower adds a distinctive identity to the skyline of the city due to its form. In addition, this award-winning building reflects Foster’s ideals about quality of work space and Swiss Reinsurance Company’s core values of sustainability. In this chapter, you will find the design value added analysis of Swiss Re Tower, demonstrated using the techniques described in this book.
Regulation of aging and innate immunity in C. elegans

Summary The free-living soil nematode Caenorhabditis elegans is a versatile model for the study of the genetic regulation of aging and of host–pathogen interactions. Many genes affecting multiple processes, such as neuroendocrine signalling, nutritional sensing and mitochondrial functions, have been shown to play important roles in determining the lifespan of C. elegans. The DAF-2-mediated insulin signalling pathway is the major pathway that regulates aging in this nematode and this role appears universal; neuroendrocrine signalling also affects aging in Drosophila and mice. Recent studies have shown that the innate immune function in C. elegans is modulated by signalling from the TGF-beta-like, the p38 MAPK and the DAF-2 insulin pathways. The requirement for the DAF-2 pathway in modulating aging and immunity suggests that these processes may be linked at the molecular level. It is well known that as humans age, immunosenescence occurs in which there is a general degradation of immune efficiency. However, the molecular mechanisms involved in this process remain unclear. In this review, we discuss the molecular mechanisms that modulate aging and immune response and attempt to suggest molecular links between these two processes.
Microstructural Evaluation of Deformation Mechanisms in Silicon Nitride Ceramics

Changes of phase composition and morphology were investigated in silicon nitride (Si3N4) before and after compressive deformation testing. Using different viscosity additives, rapid consolidation techniques were used to achieve specimens with different α-phase content and grain morphology. Low viscosity additive systems in which the phase change occurred before densification produced elongated microstructure with preferred orientation noted in the prismatic [210] direction. Limited deformation was accommodated with this grain morphology which indicated a flow stress dependency of n=1. High viscosity additive systems in which the densification occurred before the phase change produced equiaxed microstructures with virtually no preferred orientation. Enhanced deformation was accommodated in this grain morphology with an indicated flow stress dependency of n=2. Transmission electron microscope (TEM) photographs corresponded with x-ray diffraction (XRD) analysis for the grain morphology. Selected area diffraction (SAD) was used to verify phases.
The Climatic Effects of Ozone and Trace Gases

The climatic effects of a large number (>20) of trace gases, many of which have not been considered in previous investigations, are investigated. Using a one-dimensional radiative convective model the climatic impact of these gases is studied for three cases. First, using present day gas concentrations and growth rates, the effect of these gases on the equilibrium thermal structure 50 years from now is estimated. Secondly, pre-industrial gas concentrations are used to estimate climatic effects which should already have taken place. Finally, the relative importance for individual gases is calculated for a uniform 0 to 1 ppbv increase in gas concentration. The results of these calculations are: i) Increases in C02 from pre-industrial times (1850) to the present cause an increase in equilibrium surface temperature of 0.5 K. This effect due to C02 alone is amplified by a factor of 1.5 due to trace gases, ii) Increases in C02 from present concentrations to their expected levels 50 years from now result in an increase in equilibrium surface temperature of 0.7 K. The inclusion of all other trace gases enhances this increase by a factor of 2.0. The uncertainties in this factor due to uncertainties in gas concentrations is a change in enhancement from 1.5 to 3.0. iii) A number of trace gases have been identified which are of potential climatic importance based on a per ppbv increase in concentration; among these are CFC-13, 22, 116, CHF3 and CH2F2. The surface temperature effects, on a per ppbv basis, of these gases are of similar magnitude to those due to CFC11 and 12. Comparison of the present results with previous studies is also made; and sources of differences are discussed. The results of this study are discussed in much greater detail in Ramanathan et al.(1984).
The Story of Morrison v. Olson: The Independent Counsel and Independent Agencies in Watergate's Wake

The story of Morrison v. Olson is the story of the shifting fate of an idea-that through institutional design, a prosecutor could be placed beyond the influence of politics-and its fallout for the unitary executive debate over the constitutional status of independent agencies. In response to Watergate, Congress enacted an independent counsel statute that contained the critical elements that the Watergate special prosecutor model did not have: a statutory protection from presidential removal and appointment by a court. With President Reagan's inauguration, the statute's limitation on the President's power was caught in a larger constitutional battle over the central ground of the unitary executive debate: Congress's authority to limit the President's power to remove executive officers at will. Despite the Reagan Justice Department's accumulation of precedent to challenge the constitutional foundation of independent agencies, the independent counsel statute's origins as a Watergate reform provided a vehicle for the Supreme Court to validate, at least in form, Congress's authority to restrict the President's removal power and thus independent agencies in Morrison v. Olson. As notes from the Supreme Court's conference reflect, the opinion was written to "construe and uphold" the statute. Indeed, the Morrison Court premised its decision in part on the similarity between the independent counsel and the Watergate special prosecutor, not their differences. That premise holds an important wrinkle for the Court's upholding of the statute's removal restrictions. It calls into question how much protection those restrictions provide, either to the independent counsel or to independent agencies, and thus the view that Morrison amounted to a straightforward defeat for the strongly unitary executive position. It also exposes the logic which led the Court to a decision which many now view as a misjudgment. Once the Court made the analogy between the independent counsel and the Watergate special prosecutor, it was difficult not to see a set of circumstances in which the statute, as construed, would be valid. In ruling on a facial challenge, the Court needed to find only a valid application to uphold the statute. The chapter draws on the Watergate hearings, the legislative history of the independent counsel statute, the litigation leading to the Morrison decision, the Supreme Court's deliberations, including Justice Blackmun's papers, and the responses of all three branches to the Court's decision.
On The Responsibility Of MNCs: Some Reflections

The general debate on MNC and their responsibility is fraught with misperceptions. The purpose of this paper is to place the issue of accountability into a proper perspective. This would entail a clarification of the following three issues: type of sector of MNCs whose activities have generated accountability-related issues; the nature of the interests that they represent; and the types of violations which are involved. In addition, the paper will provide a set of policy recommendations on ways of enhancing accountability.
The Love of Art

The Love of Art. Pierre Bourdieu & Alain Darbel. Stanford: Stanford University Press. 1990(1969)
Nonlinear preconditioning for diffuse interfaces

A method of transforming problems with diffuse interfaces is presented which leads to equations that are easier to compute accurately. Information obtained by internal layer asymptotic analysis is utilized to motivate transformations of the dependent variables. The new evolution equations which result from this change of variables can be solved numerically in a straightforward manner. Numerical experiments indicate that truncation errors can be significantly reduced in such problems, allowing a coarser grid to be used. Applications to several well-known models are presented.
Monte Carlo Evaluation of Forward−Backward Semiclassical Correlation Functions with a Quantized Coherent State Density

The derivative formulation of the forward-backward semiclassical dynamics (FBSD) representation of time correlation functions can be expressed as an integral with respect to trajectory initial conditions weighted by the coherent state transform of a corrected density operator. Expressions are derived for evaluating the relevant matrix elements for applications of particular interest, such as normal mode, bond stretching, and velocity correlation functions at zero and at finite temperature by employing the Gaussian approximation and the discretized path integral representation of the initial density operator, respectively. The obtained expressions lend themselves naturally to integration via Monte Carlo sampling techniques. The fully quantum mechanical representation of the appropriate density operator ensures a proper treatment of zero-point effects, and the use of the coherent state representation captures important imaginary components that are absent from purely classical trajectory methods. Applications to clusters of four water molecules at room temperature are presented.
Recombination Hotspots Flank the Cryptococcus Mating-Type Locus: Implications for the Evolution of a Fungal Sex Chromosome

Recombination increases dramatically during meiosis to promote genetic exchange and generate recombinant progeny. Interestingly, meiotic recombination is unevenly distributed throughout genomes, and, as a consequence, genetic and physical map distances do not have a simple linear relationship. Recombination hotspots and coldspots have been described in many organisms and often reflect global features of chromosome structure. In particular, recombination frequencies are often distorted within or outside sex-determining regions of the genome. Here, we report that recombination is elevated adjacent to the mating-type locus (MAT) in the pathogenic basidiomycete Cryptococcus neoformans. Among fungi, C. neoformans has an unusually large MAT locus, and recombination is suppressed between the two >100-kilobase mating-type specific alleles. When genetic markers were introduced at defined physical distances from MAT, we found the meiotic recombination frequency to be approximately 20% between MAT and a flanking marker at 5, 10, 50, or 100 kilobases from the right border. As a result, the physical/genetic map ratio in the regions adjacent to MAT is distorted approximately 10- to 50-fold compared to the genome-wide average. Moreover, recombination frequently occurred on both sides of MAT and negative interference between crossovers was observed. MAT heterozygosity was not required for enhanced recombination, implying that this process is not due to a physical distortion from the two non-paired alleles and could also occur during same-sex mating. Sequence analysis revealed a correlation between high G + C content and these hotspot regions. We hypothesize that the presence of recombinational activators may have driven several key events during the assembly and reshaping of the MAT locus and may have played similar roles in the origins of both metabolic and biosynthetic gene clusters. Our findings suggest that during meiosis the MAT locus may be exchanged onto different genetic backgrounds and therefore have broad evolutionary implications with respect to mating-type switching in both model and pathogenic yeasts.
Virus trafficking – learning from single-virus tracking

This Review describes how single-virus tracking can be used to monitor the journey that viruses make through cells in exquisite detail. With specific examples of the entry, cellular transport and exit of selected viruses, the technicalities and benefits of this approach are revealed.
Employee Shareholders Or Institutional Investors? When Corporate Managers Replace Their Stockholders*

During the past decade, the shares of publicly traded companies moved increasingly into the hands of institutional investors. As large investors pressed companies to restructure, companies were observed in turn to restructure their shareholder base. Drawing on a 1989 survey of 761 US publicly traded companies, firms facing a hostile takeover environment or with large institutional holdings are found to seek greater employee stockholding. Large firms and those that had adopted takeover defences are more likely when threatened with takeovers or short-term pressures to seek more employee and less institutional stockholding. Though managers are employed by owners, investor efforts to discipline their managers can lead the latter to replace the former.
Modified predominance area diagrams for the Fe-S-O system

Using existing thermodynamic information predominance area diagrams were reconstructed for the Fe-S-O system. Isobar lines of constant total pressures of species in the vapor phase and the isopleths of constant O/S atomic ratios were added to the diagrams by solving multi-component equilibria. The diagrams were constructed at temperatures typical of pyrometallurgical roasting operations and the present roasting practice was examined critically using these modified diagrams. On a reconstruit les diagrammes de phase pour le systeme Fe-S-O en employant l'information thermodynamique existante. On a ajoute aux diagrammes, en calculant les equilibres a composants multiples, les lignes isobares a pression totale constante pour les especes en phase gazeuse ainsi que les “isoplethes” a rapports atomiques O/S constants. On a etabli les diagrammes aux temperatures typiques des operations de grillage pyrometallurgique, puis on a effectue un examen critique des methodes actuelles de grillage en employant les diagrammes ainsi modifies.
Estimating neuristor excitation thresholds

Lyapunov stability theory provides estimates of the excitation threshold for neuristor pulse propagation on a nonlinear active transmission line.
Model-based predictive control of vehicle dynamics

This paper proposes a new model-based hierarchical control strategy for the application of brake torque distribution to vehicle stability control. A three-layer control architecture is adopted, and the focus of the paper is on the intermediate layer which employs a form of model predictive control. To achieve this a non-linear vehicle model is linearised at successive time instants about non-equilibrium operating points. Simulations show that the new controller is more efficient (uses reduced brake authority) compared to a conventional rule-based control algorithm. It also has the advantage of being highly flexible for future application in fully integrated chassis systems.
Light Trapping Textures Designed by Electromagnetic Optimization for Subwavelength Thick Solar Cells

Light trapping in solar cells allows for increased current and voltage, as well as reduced materials cost. It is known that in geometrical optics, a maximum 4 n2 absorption enhancement factor can be achieved by randomly texturing the surface of the solar cell, where n is the material refractive index. This ray-optics absorption enhancement (AE) limit only holds when the thickness of the solar cell is much greater than the optical wavelength. In subwavelength thin films, the fundamental questions remain unanswered: 1) what is the subwavelength AE limit and 2) what surface texture realizes this optimal AE? We turn to computational electromagnetic optimization in order to design nanoscale textures for light trapping in subwavelength thin films. For high-index thin films, in the weakly absorbing limit, our optimized surface textures yield an angle- and frequency-averaged enhancement factor ~39. They perform roughly 30% better than randomly textured structures, but they fall short of the ray optics enhancement limit of 4 n2 ~ 50.
Management of the perineal wound after rectal excision for ulcerative colitis.

A retrospective review was conducted of 326 patients undergoing intersphincteric rectal excision for ulcerative colitis. Seventy-five patients (Group A) had rectal excision with closure of the pelvic peritoneum and packing of the pelvic space via an open perineal wound. One hundred sixty-nine patients (Group B) had excision without pelvic peritoneal closure, but with the levators and subcutaneous tissue closed and with transabdominal sump suction drainage of the pelvic space. Complete healing for Groups A and B occurred by three months in 42 and 79 percent, respectively, and by six months in 56 and 89 percent. Thirty-one percent of Group A and 9 percent of Group B were unhealed at one year, and/or required further surgery. When all 326 patients were considered, healing was achieved at three, six, and 12 months, for packed and for closed wounds, in 42 percent and 79 percent, 55 percent and 89 percent, 66 percent and 91 percent, respectively. All these differences are highly significant (P<0.0001). The incidence of small-bowel obstruction requiring surgery during follow-up was similar whether the pelvic peritoneum was closed (15.5 percent) or left open (15.7 percent). Other factors which adversely affected perineal wound healing were younger age, a short history of disease, a two-stage proctocolectomy especially for persistent severe rectal disease, and the presence of perianal disease.
Helical Turbulence Prevails over Inertial Waves in Forced Rotating Flows at High Reynolds and Low Rossby Numbers

AbstractA study of spectral laws for helical turbulence in the presence of solid body rotation up to Reynolds numbers Re ~ 1 × 105 and down to Rossby numbers Ro ~ 3 × 10−3 is presented. The forcing function is a fully helical flow that can also be viewed as mimicking the effect of atmospheric convective motions. Variants of a model developed previously by Baerenzung et al. are tested in the helical case against direct numerical simulation (DNS), using data from a run on a grid of 15363 points; its efficiency is also contrasted against a spectral large-eddy simulation (LES) by Chollet and Lesieur, as well as an underresolved DNS. The model including the contribution of helicity to the spectral eddy dissipation and eddy noise behaves best, allowing the recovery of statistical features of the flow. Even if the model is based on isotropic assumptions, the authors demonstrated in a previous study that the small scales of flows at moderate Rossby number can be considered to be isotropic in the range of paramete...
Epigenome analyses using BAC microarrays identify evolutionary conservation of tissue-specific methylation of SHANK3

CpG islands are present in one-half of all human and mouse genes and typically overlap with promoters or exons. We developed a method for high-resolution analysis of the methylation status of CpG islands genome-wide, using arrays of BAC clones and the methylation-sensitive restriction enzyme NotI. Here we demonstrate the accuracy and specificity of the method. By computationally mapping all NotI sites, methylation events can be defined with single-nucleotide precision throughout the genome. We also demonstrate the unique expandability of the array method using a different methylation-sensitive restriction enzyme, BssHII. We identified and validated new CpG island loci that are methylated in a tissue-specific manner in normal human tissues. The methylation status of the CpG islands is associated with gene expression for several genes, including SHANK3, which encodes a structural protein in neuronal postsynaptic densities. Defects in SHANK3 seem to underlie human 22q13 deletion syndrome. Furthermore, these patterns for SHANK3 are conserved in mice and rats.
Maceral/ microlithotype partitioning with particle size of pulverized coal: Examples from power plants burning Central Appalachian and Illinois basin coals

Pulverized coals from eleven power plants burning Central Appalachian coal blends and eight power plants burning Illinois Basin coal blends were studied in order to assess the petrographic nature of industrial-scale coal grinding. All coals were high volatile bituminous. Coals were wet screened at 100 (150 μ), 200 (75 μ), 325 (about 40 μ), and 500 (about 25 μ) mesh. Petrographic analysis of the whole coals and size fractions consisted of a combined maceral and microlithotype analysis. Microlithotype analysis, in particular, provides a reasonable approximation of the whole-particle composition at the scale of utility coal pulverization. In the size fractions, duroclarite, the most abundant trimaceral microlithotype, is most abundant in the coarsest fraction and least abundant in the finest fraction. Vitrite, the most abundant monomaceral microlithotype, exhibits the opposite trend. Duroclarite becomes more enriched in vitrinite towards the finer sizes. The partitioning of microlithotypes and the partitioning of macerals within the microlithotypes is indicative of the relative brittle nature of vitrite compared to the hard-to-grind trimaceral microlithotypes. Increased vitrinite in duroclarite is an indication that the microlithotype within the particular size fraction is more brittle than relatively vitrinite-depleted duroclarite in coarser fractions. The relative grindability of microlithotypes will, in turn, impact combustion efficiency.
Availability of Lake Trout Reproductive Habitat in the Great Lakes

Abstract A decades-long program to reestablish self-sustaining stocks of lake trout (Salvelinus namaycush) in the four lower Great Lakes produced excellent fisheries supported by stocked fish. These fish spawned widely and small numbers of their offspring were collected intermittently from Lakes Michigan, Huron, and Ontario, but no self-sustaining stocks were established. In this paper we address habitat sufficiency as a factor in the failure of stocked lake trout to established self-sustaining populations in the four lower Great Lakes. We present the previously unpublished results of lake trout spawning habitat surveys conducted at seven sites in the Great Lakes since 1987 and we compare them with the published results of similar surveys conducted at 24 other sites in the four lower lakes since 1981. Our evaluation indicates all but two of these sites can support the production of viable fry from spawnings by the shallow-water strains of lake trout that are stocked in the Great Lakes. However, some of the best spawning, egg, and fry habitat in the lower Great Lakes seems to be at deeper offshore sites that may be unattractive to these shallow-water strains. Thus, we suggest also stocking the lower four lakes with strains from Lake Superior that might more fully exploit the best spawning habitat at these deeper, offshore sites.
Optofluidic Manipulation of Particles for Separation, Purification, and Analysis

An optofluidic system and applications are described where biological samples are characterized and separated in a microfluidic device based upon their intrinsic properties. As an example, optical force differences have been measured between various human blood cells including lymphocytes, monocytes, granulocytes, and erythrocytes indicating the potential to harness optical force differences to separate blood cells. Article not available.
Cardiomyocyte Death: Insights from Molecular and Microstructural Magnetic Resonance Imaging

Cardiomyocytes can die via necrosis, apoptosis, and autophagy. Although the molecular signals and pathways underlying these processes have been well elucidated, the pathophysiology of cardiomyocyte death remains incompletely understood. This review describes the development and application of novel imaging techniques to detect and characterize cardiomyocyte death noninvasively in vivo. It focuses on molecular and microstructural magnetic resonance images (MRIs) and their respective abilities to image cellular events such as apoptosis, inflammation, and myofiber architecture. These in vivo imaging techniques have the potential to provide novel insights into the mechanisms of cardiomyocyte death and to help guide the development of novel cardioprotective therapies.
Contrast bone cement

The effects of adding 1.0 cc of aqueous methylene blue dye as a visual contrast agent to a standard 40 g pack of acrylic bone cement are determined. These cements are evaluated: Simplex P (Radiopaque), Zimmer Bone Cement, and Zimmer LVC Bone Cement. Seven tests were performed. Leach out is less than 2.0% and was undetectable after day 8. Biocompatibility using a rabbit model shows contrast and white cement to be equivalent. Tension, compression, and 3- and 4-point bending strengths are not significantly altered except for a slight increase in 4-point bending strength for contrast Zimmer (regular) bone cement. Dough, set, and working times are decreased by 30-150 s. The ASTM F451 intrusion standards are met for all three contrast cements. Viscosity increases more rapidly for contrast cement, but remains sufficiently low (less than 100 N-s/m2) early after mixing to allow good penetration into bone. Ease of removal and visualization of contrast cement are shown by revision of cemented femoral total hip components in synthetic and cadaver femurs and by debriding cement particles from a soft tissue background coated with blood. The use of contrast bone cement appears to be both safe and efficacious for use in initial and revision total joint replacements. Because of the decreased working times, its use is recommended only by experienced surgeons.
The binding energy of the triton with a velocity-dependent potential

Abstract We have made a variational calculation of the binding energy of the triton using a two-body velocity-dependent central potential adjusted to fit two-body low and high energy scattering data and the binding energy of the deuteron. We have used a set of one, two and three parameter trial functions. The values of the binding energy of the triton obtained with these trial functions suggest that convergence has been nearly obtained. Obviously, the highest value for the binding energy is obtained with the three-parameter trial function and is equal to 7.17 MeV. We have also calculated the Coulomb energy of He3 by the usual perturbation method and obtain a value equal to 0.663 MeV. These values of the binding energy of the triton and the Coulomb energy of He3 agree reasonably well with similar calculations using repulsive hard core potentials but are lower than the experimental values.