cssi/SciSciGPT-SciSciNet huggingface dataset:
Point-of-care COVID-19 testing in the emergency department: current status and future prospects.

Introduction This expert review outlines current and future point of care technologies for the diagnosis of the SARS-CoV 2 virus, which is responsible for causing coronavirus disease COVID-19 in the emergency department. COVID-19 first emerged in late 2019 and is responsible for a range of presentations from minor upper respiratory tract symptoms to severe pneumonia and multisystem organ failure. Among the technologies available include the gold standard of molecular point of care tests as well as antigen detection tests. Areas covered We discuss point of care molecular tests including multiplex, targeted and single plex panels as well as various antigen testing methodologies in terms of availability and performance characteristics. In addition, we focus on current testing best practices and considerations for point of care testing in the emergency department based on a search of the literature available in PubMed to date and a review of FDA and CDC guidance. Expert opinion While there have been many advances in SARS-coV2 point of care testing, there remain challenges to implementation in the emergency department setting. A paradigm shift is needed to improve diagnosis and clinical outcomes.
Social media news deserts: Digital inequalities and incidental news exposure on social media platforms:

Some people live in social media “news deserts,” while others are embedded in online networks that are rich in news content. These news deserts represent a new form of digital inequality—distinct f...
Disparities in distribution of information resources in the city of Philadelphia: Spatial analysis of socio-demographic and information resource variables

This study explored the use of GIS techniques to spatially explore and identify areas where provision of public library and information services are insufficient. By identifying the spatial distribution of inequity of access to information services in Philadelphia. Geographic analysis techniques were applied to investigate the existence of a relationship between spatial orientation, socio-economic factors and information access. The findings of this study suggest the existence of a spatial pattern in relation to disparity of the distribution of information resources in Philadelphia. A secondary analysis utilized the aforementioned findings to assess the existence of patterns of library service provision on a limited data set. The results of analyses indicate that in the disadvantaged areas of Philadelphia, public libraries play the role of information access gateways/bridges. The findings can be used to better locate the future public library and information service centers in the city of Philadelphia.
INELASTIC RESPONSE OF RESTRAINED STEEL TUBES

Eighteen specimens made from 1 in. (25-mm) square tubes with welded gusset plates were tested under repeated axial loading. Length of the specimens varied from 20 in. to 54 in. (510mm to 1,370mm) and their slenderness ratio varied from 30 to 160. The objective of this investigation was to study the effects of connection flexural strength and stiffness and change of member length on the hysteresis behavior. From the parametric study it was concluded that the hysteresis behavior of flexurally restrained axial members is most influenced by a single parameter — the effective slenderness ratio. The results were compared with recent theoretical predictions and were in excellent agreement for members of larger slenderness ratio, yet with some slight differences. Other observations are that the maximum compressive load decreased and member length increased with number of cycles.
Phaseless diagnostics for non-rectangular near-field antenna measurement systems

The emergence of the near-field phaseless measurements as viable solutions to the antenna measurements at higher frequencies has created a lot of enthusiasm among the researchers. There had been an ongoing desire to enhance these techniques to a level where they can perform as accurate as the current amplitude-phase near-field techniques. The implementation of these techniques on different types of chambers might require some special treatments. In non-rectangular near-field systems such as bi-polar and plane-polar there is a need to co-rotate the probe with the antenna under test to maintain the polarization fixed. It is shown that in near-field systems if one measures two set of orthogonal data then there would be no need for the simultaneous probe co-rotation. Although there is no need for this extra motion in non-rectangular amplitudephase near-field systems for phaseless techniques the probe co-rotation become extremely important. This paper discusses this issue and has proposed an iterative technique to alleviate this extra motion. The ability of the proposed method in diagnosing a typical aperture antenna with faulty sections is also examined through simulations
A Note on Interactive Theorem Proving with Theorem Continuation Functions

Abstract A simple technique for using theorem continuation functions interactively with HOL's subgoal package is presented. An interesting aspect of the technique is that it hinges on the existence of assignable variables in ML.
Systematically Eradicating Data Injection Attacks Using Security-Oriented Program Transformations

Injection attacks and their defense require a lot of creativity from attackers and secure system developers. Unfortunately, as attackers rely increasingly on systematic approaches to find and exploit a vulnerability, developers follow the traditional way of writing ad hoc checks in source code. This paper shows that security engineering to prevent injection attacks need not be ad hoc. It shows that protection can be introduced at different layers of a system by systematically applying general purpose security-oriented program transformations. These program transformations are automated so that they can be applied to new systems at design and implementation stages, and to existing ones during maintenance.
Revealed Preferences for Corporate Leverage

I consider a simple model of dynamic capital structure with adjustment costs, and I show how financial decisions reveal firms’ preferences for leverage. I show that the most commonly used empirical models of capital structure (the partial adjustment model, e.g. Fama and French (2000) and the financial deficit model, e.g. Shyam-Sunder and Myers (1999)) are mis-specified. Estimating a correctly specified model yields new insights and solves spurious puzzles: The expected future financial deficit is a significant determinant of the current choice of debt versus equity, and profitable firms have a higher target leverage. However, while the value functions that I estimate display qualitatively sensible properties, they also appear extremely flat for moderate values of leverage, which is inconsistent with tax-based theories. The methodology that I propose can be readily extended to test the importance of other determinants of capital structure decisions. As an application, I show that CEO tenure flattens the left part of the estimated value function, which is consistent with agency theories. Corporate finance textbooks summarize the static trade-off model of capital structure with a simple picture of the value of the firm as a function of its leverage, as shown on Figure 1. In fact, other theories can be represented by an objective function, together with a pair of adjustment cost functions for debt and equity. In the cumulative pecking order theory, the objective function is flat and the adjustment costs are much higher for equity issues than for debt issues. The agency view is that the objective function represents managerial preferences, as opposed to the value of the firm for its claim holders. My contribution in this paper is to estimate the objective function "revealed" by actual firms’ decisions. I use the simplest theoretical framework to derive an empirically estimable equation. Despite its simplicity, this equation offers new insight into capital structure dynamics: As predicted by the theory, the expected future financial deficit is a significant determinant of current decisions to issue debt or equity. I also find that profitable firms have a higher target leverage ratio, and that adjustment costs for debt are smaller than for equity. However, while the objective functions that I estimate display qualitatively sensible properties, they also appear extremely flat for moderate values of leverage, which is inconsistent with tax-based theories. The methodology that I propose can be readily extended to test the importance
Reactive power management of co-located residential PVs for radial distribution systems

Electricity plays an important and leading role in the flourishing of the world economy as sustainable and cost-efficient energy carrier for everyday needs. With the fast economic expansion in the developing areas, the cost of electricity has increased accordingly. The use of renewable distributed generation (DG) technologies and "green power" can provide a significant environmental benefit, and their costs continue to dropping. Utilities will try to get more injected renewable energy to our distribution network. This paper presents a reactive power management method based optimal power flow to calculate optimal DG power output and necessary voltages at buses and incremental costs in the distribution system integrating high penetration rate of renewable energy resources. The proposed method is able to minimize the electricity cost by cutting the power transferred from the grid and provide the co-optimized operation strategy for distribution system with residential photovoltaics (PVs), Case study is also presented to demonstrate the feasibility of proposal method.
Government Procurement Policy, Patent Royalties and the Myth of 'Discrimination' Against Free and Open Source Software Developers

Government policy makers have been confronted with requests by various lobbying groups to “level the playing field” for Free and Open Source Software (FOSS) developers through policies that would remove the ability of patent holders to seek royalties for the use of their technologies in standards. These groups have made claims that the Fair Reasonable and Non Discriminatory (FRAND) licensing framework that is used in most standards setting organizations (SSOs), and which allows for the inclusion of a royalty term, are incompatible with or discriminate against FOSS developers. Part I takes closer look at these claims, as well as the current market for ICT products (those covered by a FOSS license, those covered by traditional commercial licenses and those hybrid products covered by both) and finds that there is no evidence that FOSS developers are unable to implement the wide range of standards that are currently covered by FRAND commitments. Part II looks at the recent work of several commentators who have examined this issue in a detailed and empirical manner and have found not just that the claims of exclusion by FRAND (and patent royalties in particular) are exaggerated, but that there are documented instances of the successful interplay between FRAND terms (including royalties) and FOSS licenses (even the GPL). The paper concludes that absent evidence of market failure, government procurement officers should leave it to market participants to work out agreements that allow standards subject to FRAND commitments and FOSS licensed products to co-exist as they do today. The current IP licensing framework (including the possibility of a royalty) effectively balances the rights of innovators and the interests of implementers of all business models, resulting in compelling products for consumers at competitive prices.
Mode of Transmission of Pseudomonas aeruginosa in a Burn Unit and an Intensive Care Unit in a General Hospital

The transmission of Pseudomonas aeruginosa was studied in the burn unit and the intensive care unit of a 650-bed hospital. There was a tendency among patients in the burn unit to yield more than one type of P. aeruginosa, and several patients shared the same types at a particular point in time, suggesting cross-contamination among patients. Similar observations were made in the intensive care unit. Cultures from the hands of nurses caring for these patients yielded the same types of P. aeruginosa, suggesting the direct handling of patients by the nursing personnel to be the principal mode of transmission.
LOGICS APPROPRIATE TO EMPIRICAL THEORIES

To those like myself who are mainly concerned with the methodology of the empirical sciences, the present symposium is both sobering and encouraging. It is sobering as one thinks of the scientific contrast between the majority of papers read here and the standard sources in the methodology and philosophy of science. Yet it is encouraging, because the hope is engendered that many of the methods, and perhaps above all, the intellectual standards of these papers, will extend themselves in a natural way to logical investigations of the empirical sciences. The logical and philosophical foundations of physics, for example, seem to be at about the stage where the foundations of mathematics were during most of the nineteenth century. Nearly any physicist and a large number of philosophers are prepared to deliver at a moment’s notice a lecture on the foundations of quantum mechanics. The situation is far different with respect to the foundations of mathematics. With an ever-increasing volume of deep and rigorous results, mathematicians unacquainted with the literature are not prone to deliver casually-put-together obiter dicta on logic and related topics.
Factors influencing the acceptability of coitus interruptus among Latina teens and young adults.

ABSTRACT Objectives: The purpose of this study was to examine factors associated with the acceptability of coitus interruptus, or withdrawal, as a contraceptive method among a cohort of Latinas. Method: We conducted face-to-face interviews with a cohort of young, urban Latinas in Chicago to assess factors associated with willingness to use withdrawal. Findings: Two hundred seventy-three sexually experienced women aged 13–25 years were included in the analysis. Respondents were predominately Mexican American (83.9%) and born in the United States (69.2%) or Mexico (27.1%). One hundred sixty-two women expressed willingness to use withdrawal. In a multivariable analysis, factors associated with willingness to use withdrawal included belief in its efficacy, having communicated with one's partner about waiting to have sex, and lack of knowledge of oral contraceptives. Conclusion: Beliefs, knowledge, partner variables and contraceptive attitudes were important factors related to the acceptability of withdrawal a...
The Experience Sampling Method

The Experience Sampling Method (ESM) is a research procedure for studying what people do, feel, and think during their daily lives, It consists in asking individuals to provide systematic self-reports at random occasions during the waking hours of a normal week. Sets of these self-reports from a sample of individuals create an archival file of daily experience.
Assessing intracranial vascular compliance using dynamic arterial spin labeling

Vascular compliance (VC) is an important marker for a number of cardiovascular diseases and dementia, which is typically assessed in the central and peripheral arteries indirectly by quantifying pulse wave velocity (PWV), and/or pulse pressure waveform. To date, very few methods are available for the quantification of intracranial VC. In the present study, a novel MRI technique for in-vivo assessment of intracranial VC was introduced, where dynamic arterial spin labeling (ASL) scans were synchronized with the systolic and diastolic phases of the cardiac cycle. VC is defined as the ratio of change in arterial cerebral blood volume (ΔCBV) and change in arterial pressure (ΔBP). Intracranial VC was assessed in different vascular components using the proposed dynamic ASL method. Our results show that VC mainly occurs in large arteries, and gradually decreases in small arteries and arterioles. The comparison of intracranial VC between young and elderly subjects shows that aging is accompanied by a reduction of intracranial VC, in good agreement with the literature. Furthermore, a positive association between intracranial VC and cerebral perfusion measured using pseudo-continuous ASL with 3D GRASE MRI was observed independent of aging effects, suggesting loss of VC is associated with a decline in perfusion. Finally, a significant positive correlation between intracranial and central (aortic arch) VC was observed using an ungated phase-contrast 1D projection PWV technique. The proposed dynamic ASL method offers a promising approach for assessing intracranial VC in a range of cardiovascular diseases and dementia.
Toward the Quantification of Phonic Interference

This paper suggests a method for measuring the degree of interference that takes place in the speech of bilingual subjects. The technique is adapted from previous studies on the reception of speech in noise and is used in the first instance to measure interference at the phonic level. Various types of interference are examined and measured in a pilot experiment.
Palantir: Crowdsourced Newsification Using Twitter

Palantir is a real-time collaboration system that is designed for people who glean information from Twitter during an event, and would like to consolidate Tweets into stories as and when they happen. The system is designed to easily let people share annotated Tweets from mobile clients, and use a web client to track Tweets, and consolidate these Tweets into stories that can later be published.
The Effect of Changed Environmental Conditions Upon the Results of College Examinations

(1940). The Effect of Changed Environmental Conditions Upon the Results of College Examinations. The Journal of Psychology: Vol. 10, No. 2, pp. 293-301.
A general method for the calculation of lineshapes of molecular spectra

Abstract A general method for the calculation of lineshapes of molecular spectra, based on the theory of Green's function, is presented. It is applied to a hypothetical seven sites exchanging system.
Monitoring adolescent gambling in Minnesota.

Youth gambling was investigated in a prospective sample of 532 Minnesota adolescents and young adults. Of particular interest was the possible impact among the study sample of a recent state lottery and of reaching the legal age for gambling on changes in the rate and type of gambling. Overall rates of gambling involvement and pathological gambling did not change across the 1.5 year interval. However, a preference for certain types of gambling activities (e.g., lottery, casino machines) significantly increased, whereas more informal and unregulated games (e.g., betting on games of personal skill) significantly decreased. Also, access to gambling activities by underage youths was high, suggesting the need for tighter controls of legalized games and greater awareness of this problem by the gaming industry and public health officials.
Steady-state penetration of transversely isotropic rigid/perfectly plastic targets

Abstract Axisymmetric deformations of a transversely isotropic, rigid/perfectly plastic target being penetrated by a long rigid cylindrical rod with an ellipsoidal nose have been analyzed. The deformations of the target appear steady to an observer situated at the penetrator nose tip. The contact between the target and the penetrator is assumed to be smooth. Computed results show that the deformation field adjacent to the penetrator nose surface is significantly influenced by the nose shape, and the ratio of the yield stress in the axial direction to that in the transverse direction. The axial resisting force experienced by the penetrator is found to depend strongly upon the nose shape and the ratio of the yield stress in the axial to that in the transverse direction, but weakly upon the square of the penetration speed.
Electron- and hole-hopping amplitudes in a diatomic molecule. II. Effect of radial correlations

We continue our study of electron- and hole-hopping amplitudes in diatomic molecules. Here, we go beyond the Hartree approximation and use two different orbital exponents for the two-electron atom. It is found that the difference in hopping amplitudes between electrons and holes (\ensuremath{\Delta}t) is enhanced when the effect of radial correlations is taken into account. A tight-binding model with two orbitals per site is used to represent the results of the first principles calculation and gain insight into the physical origin of the quantity \ensuremath{\Delta}t.
Micronets for electron microscopy

Abstract Quantities of grids can be easily and reliably prepared with supporting nets of carbonized Parlodion if just a few principles and procedures are understood and practiced 1 . Film nets are best cast on properly prepared, hydrophobic glass slides. Highly consistent results are achieved if slides receive a protracted soaking in a saturated solution of ferric stearate in benzene. Excess then is washed away, presumably leaving little but the adsorbed layer. 2. Nets are most reliably formed by exposing wet films of 0.4–0.6% Parlodion in amyl acetate to steam. 3. The same Parlodion solutions then can be painted on the slides to outline selected areas of nets. This serves the additional purpose of simplifying the floatation of the nets. 4. Grids with dried nets then require baking at 170–180°C to eliminate attenuated films which otherwise span the meshwork. 5. Finally the nets are heavily coated with carbon to achieve stability, and a wetting agent then can be used to render them hydrophilic.
Hypertension and albuminuria in chronic kidney disease mapped to a mouse chromosome 11 locus

Chronic kidney disease (CKD) is a key cause of hypertension and a potent independent risk for cardiovascular disease. Epidemiological studies suggest a strong genetic component determining susceptibility for renal disease and, by inference, the associated cardiovascular risk. With a subtotal nephrectomy model of kidney disease, we found the 129S6 mouse strain to be very susceptible to the development of hypertension, albuminuria, and kidney injury, whereas the C57BL/6 strain is relatively resistant. Accordingly, we set out to map quantitative trait loci conferring susceptibility to hypertension and albuminuria using this model with F2 mice. We found significant linkage of the blood pressure trait to two loci. At D11Mit143, mice homozygous for the 129S6 allele had significantly higher systolic blood pressure than mice heterozygous or homozygous for the C57BL/6 allele. Similarly, at D1Mit308, there was an excellent correlation between genotype and the blood pressure phenotype. The effect of the chromosome 11 locus was verified with a separate cohort of F2 mice. For the albuminuria trait, a significant locus was found at D11Mit143, which overlaps the blood pressure trait locus. Our studies have identified a region spanning ∼8 cM on mouse chromosome 11 that is associated with susceptibility to hypertension and albuminuria in CKD.
Link mining applications: progress and challenges

This article reviews a decade of progress in the area of link mining, focusing on application requirements and how they have and have not yet been addressed, especially in the area of complex event detection. It discusses some ongoing challenges and suggests ideas that could be opportunities for solutions. The most important conclusion of this article is that while there are many link mining techniques that work well for individual link mining tasks, there is not yet a comprehensive framework that can support a combination of link mining tasks as needed for many real applications.
The effect of grain size on local deformation near a void-like stress concentration

Abstract The deformation-induced nucleation, growth, distortion, and coalescence of voids have been the subject of numerous experimental, theoretical, and computational studies. However, a vast majority of prior work does not consider the role of the local microstructure on void behavior. The present work considers an isolated cylindrical hole undergoing far-field tensile deformation in cartridge brass (70% Cu, 30% Zn). A polycrystal plasticity model was employed to examine the role of grain-size-to-void-size ratios of 0.14, 1, and 7. These numerical simulations clearly demonstrated that when the grain size is comparable to or larger than the void, inhomogeneous deformation of the microstructure can distort and even overwhelm the role of the void in concentrating plastic strain. To confirm and further elucidate these effects, deformation of brass tensile bars with microscale cylindrical holes was performed in situ in a Scanning Electron Microscope (SEM). This approach permitted Electron Backscattered Diffraction (EBSD) measurements of the evolution of local intragrain misorientation and full-field Digital Image Correlation (DIC) measurements of the evolution of intragranular strain fields. As expected, when the hole diameter decreased in relation to the grain size, the effects of local microstructure became increasingly important. In an extreme case, the strain localization due to the hole was completely confined within a single grain. In light of these results, existing continuum-based methodologies to represent ductile fracture, such as the Gurson-Tvergaard-Needleman approach and shear-modified variants, may need to be further modified to include these prominent microstructural effects. Such microstructurally-sensitive representations provide one pathway towards stochastic/statistical models for ductile tearing.
Excitons and excitation transfer in the photosynthetic unit of purple bacteria

Photosynthetic purple bacteria employ an antenna system to absorb sunlight and transfer electronic excitation to a centrally located protein, the photosynthetic reaction center. The antenna system employs for this purpose a hierarchy of circular bacteriochlorophyll aggregates. For the case of a particular light harvesting protein with known structure, one- and two-exciton spectra of its circular bacteriochlorophyll aggregate are determined by means of an effective Hamiltonian description. A detailed geometric model for the complete antenna system of the purple bacterium Rhodobacter sphaeroides is provided by molecular modelling and its bacteriochlorophyll aggregates are investigated, employing also an effective Hamiltonian. Transfer times within the complete antenna system and from the antennae to the reaction center are calculated.
INHIBITION OF BACTERIAL PHENYLALANINE UTILIZATION AND ACTIVATION.

Abstract The inhibitory effects of a number of phenylalanine analogs upon a phenylalanine-activating enzyme of Escherichia coli 9723 are compared with certain actions of the analogs in vivo . Phenylalanine analogs that served as substrate in the absence of phenylalanine for the previously reported phenylalanine-activating enzyme are also effective inhibitors of enzymatic phenylalanine-hydroxamate formation in vitro . A group of analogs, typified by p -tolylalanine, that are not growth inhibitors of wild type E. coli and are not substrates for the phenylalanine-activating enzyme, has been found inhibitory to enzymatic phenylalanine activation in vitro ; analogs of this group also inhibit utilization of exogenous phenylalanine by a phenylalanine-requiring mutant strain of E. coli 9723. The inactivity of this group of analogs as growth inhibitors of the wild type may result from their inability to reach the specific intracellular site of the activating enzyme in effective concentrations, or, less likely, from the existence of a separate activating system for biosynthetic phenylalanine.
Taylor's Hypothesis and High–Frequency Turbulence Spectra

Abstract Lumley's model for interpreting frequency spectra of streamwise velocity in high-turbulence level flows assumes 1) that the convection velocity fluctuations and the convected finestructure are statistically independent, and 2) that the characteristic function of convection velocity fluctuations can be represented by the first two terms of its series expansion. The first assumption is consistent with numerous experimental results, and we test the second with an alternative assumption: that the convection velocity fluctuations are Gaussian. The two models are found to agree well up to moderately high fluctuation levels, thus giving support for Lmnley's model in atmospheric boundary layer applications. We generalize his model to spectra of lateral velocity and a scalar, and calculate how various large-wavenumber spectral properties are disturbed by convection velocity fluctuations. The inertial subrange spectra are found to be affected relatively little, but serious spectral distortion is found at l...
Concept of soil fertility and soil productivity: evaluation of agricultural sites in the Czech Republic

This paper describes the methods used to assess soil fertility and model soil productivity for agricultural land in the Czech Republic. The assessment is based on the obtained crop yields and the various factors that influence those yields. These factors incorporate the physical characteristics of the soil, the climate and the applied agricultural practices. They have been quantified from monitoring ∼500 homogeneous plots of land covering a total area of 9200 ha since 2002. Soil productivity has been modelled using crop yield and crop production functions. A linear production function has been developed through factor analysis. The presented example details wheat production under average conditions for the Czech Republic. It is possible to use the crop production function to improve our understanding of the soil system, as well as for better identification of soil characteristics for economic and environmental purposes.
Collagen prolyl hydroxylation in WI-38 fibroblast cultures: action of hydralazine.

The action of hydralazine on collagen prolyl hydroxylation was studied in a cell culture system using WI-38 fibroblasts. The prolyl hydroxylation level was determined by a method involving the digestion of collagen by bacterial collagenase and the examination of specific peptides. The presence of low concentrations of hydralazine (0.2 mM) in both “young” and “old” fibroblast cultures strongly inhibited collagen prolyl hydroxylation. The degree of inhibition was greater in serum-deficient cultures. No significant improvement in the degree of hydroxylation was observed by increasing either ascorbate or iron levels in the hydralazine-containing cultures in which hydroxylation was inhibited. Some of the reported side effects of hydralazine seen in patients might be related to its inhibitory effects on mixed function oxidative (MFO) hydroxylation systems. While the ascorbate dependence of the prolyl hydroxylase system of WI-38 decreased with the “age” of the culture, hydralazine inhibition of hydroxylation was dramatic with cultures of all “ages”.
Interpretation of the lunar microwave brightness temperature spectrum: feasibility of orbital heat flow mapping

The feasibility of an orbital mapping of heat flow by means of microwave radiometers is examined on the basis of a detailed model of the lunar regolith. The results obtained are discussed in terms of contributions of physical properties and regolith structure to the spectral signature of lunation-averaged brightness temperatures. Even for regions for which remote heat flow detection is not feasible, detailed interpretations of remote measurements in terms of physical properties and regolith structure could be made by means of the model presented. Surface and subsurface scattering effects are considered in evaluating possible wavelength dependencies of the microwave emissivity.
Aspect ratio effect on natural convection in water near its density maximum temperature

Abstract The effect of the aspect ratio on natural convection in water subjected to density inversion has been investigated in this study. Numerical simulations of the two-dimensional, steady state, incompressible flow in a rectangular enclosure with a variety of aspect ratios, ranging from 0.125 to 100, have been accomplished using a finite element model. Computations cover Rayleigh numbers from 103 to 106. Results reveal that the aspect ratio, A, the Rayleigh number, Ra, and the density distribution parameter, R, are the key parameters to determine the heat transfer and fluid flow characteristics for density inversion fluids in an enclosure. A new correlation for predicting the maximum mean Nusselt number is proposed in the form of Nu max =a−b log (A) , with the constants a and b depending on density distribution number R. It is demonstrated that the aspect ratio has a strong impact on flow patterns and temperature distributions in rectangular enclosures. The stream function ratio Ψinv/|Ψreg| is introduced to describe quantitatively the interaction between inversional and regular convection. For R=0.33, the density inversion enhancement is observed in the regime near A=3.
Interactive effects of boron, selenium, and dietary protein on survival, growth, and physiology in mallard ducklings

High concentrations of boron (B) and selenium (Se) have been found in aquatic food chains associated with irrigation drainwater. Total biomass of invertebrates, a major source of protein for wild ducklings, is sometimes diminished in agricultural drainwater ponds contaminated with Se and B. Day-old mallard (Anas platyrhynchos) ducklings received an untreated diet (controls) containing 22% protein or diets containing 15 ppm (μg/g) Se (as selenomethionine), 60 ppm Se, 1,000 ppm B (as boric acid), 15 ppm Se with 1,000 ppm B, or 60 ppm Se with 1,000 ppm B. In a concurrent experiment, the above sequence was repeated with a protein-restricted (7%) but isocaloric diet. After four weeks, blood and tissue samples were collected for biochemical and histological examination. With 22% protein and 60 ppm Se in the diet, duckling survival and growth was reduced and histopathological lesions of the liver occurred. Boron alone caused some reduction in growth. Several interactive effects occurred between B and Se, including further reduction in growth, and increases in plasma glutathione reductase activity, hematocrit, hemoglobin and plasma protein concentrations. With 7% protein, the growth of controls was less than that with 22% protein, 60 ppm Se caused 100% mortality, and growth effects of 15 ppm Se and 1,000 ppm B alone were more pronounced than with 22% protein. Selenium accumulation increased in the liver with 7% protein. Interactive effects were greater for Se and B with 7% protein than with 22% protein and included significant mortality and enhanced accumulation of Se in the liver. These findings suggest the potential for more severe toxicological effects of Se and B independently and interactively on duckling survival and development when dietary protein is diminished.
Regulating the isotypic and idiotypic profile of an anti-PC antibody response: lessons from peptide mimics.

Protection against microbial invasion depends not only on the host’s ability to mount an immune response, but on its ability to mount the correct immune response. Whether an antibody response is protective or not depends on both the fine antigenic specificity, that may be associated with particular idiotypes and epitope binding characteristics, and the isotype, determining antibody effector function. Thus, both the variable and the constant region of the antibodies induced by a peptide mimotope must be considered when assessing the success of any immunization. Phosphorylcholine (PC), an epitope present on the cell-wall C-polysaccharide of all pneumococcal serotypes, is capable of eliciting a protective antibody response to pneumococcal infection in mice and provides an attractive model system for understanding the immune response generated by peptide mimics. In this system, both the idiotype and isotype of protective antibodies have been determined and the characteristics of the in vivo response are well described and highly reproducible. We describe here the immune response generated by two peptide mimics of PC. Mice immunized with the peptides developed antibodies binding PC and C-polysaccharide. The idiotypic profile of the response differed depending on the peptide, but never included canonical T15+ antibodies. The isotype of the response to peptide mimics differed depending on a combination of peptide and adjuvant, and included both IgG2a and IgG2b antibodies which are not typically seen in the response to PC. Thus, peptide mimotopes may elicit anti-polysaccharide responses, but fail to elicit the idiotypes and isotypes observed in the protective response to the microbial antigen.
Creating Standardized Metrics and Benchmarking for Health, Absence and Productivity Management Programs: The EMPAQ Initiative

Prudent feedback from employer surveys has indicated that standardized metrics and integrated decision-support tools are essential for identifying opportunities to improve programs and reinforce a culture of health and productivity. This article reports on an innovative, nationally standardized metric and benchmarking initiative that provides employers with practical workplace tools and solutions to evaluate the effectiveness of their company’s health, absence and productivity management programs, including workers’ compensation, family and medical leave, disability, incidental absence, employee assistance programs and group health. The initiative, titled EMPAQ (Employer Measures of Productivity, Absence and Quality), was created in 2001 by the National Business Group on Health’s Council on Employee Health and Productivity (CEHP). EMPAQ was successfully launched and implemented by many major companies nationwide in 2003. EMPAQ data collection, analysis and reporting are performed through a partnership wit...
Concerns Regarding Adult Children's Assistance: A Comparison Of Young–Old and Old–Old Parents

This study describes differences between young-old (ages 60-74) and old-old (ages 75-90) parents' concerns regarding assistance provided by adult children. Old-old parents expressed more concern regarding amounts of help than did younger parents; there were no age differences in levels of concern regarding help outcomes. The percentage of children receiving parents' help and reliance on formal services predicted level of concern regarding help outcomes for the young-old parents, but not the old-old parents. Familism values and the extent of help received predicted level of concern regarding help amounts for the old-old parents, but not for younger parents. Implications for interventions to minimize parents' concerns and for further study of family assistance to the older people are discussed.
Solvent effects on thiamine–enzyme model interactions. 2,3,4-Trimethylthiazolium iodide, a model for interaction with negative charges

We have studied the solvent dielectric constant dependence of the ionic association process in 2,3,4-trimethylthiazolium iodide as a model for the interaction of the thiazolium ring of thiamine with a carboxylate or other negatively charged species in enzymic processes requiring thiamine pyrophosphate as a co-factor. The Kass value for the ion pair (as measured by u.v. spectroscopy) increases as the solvent dielectric constant decreases from 3.4 in pure water to 175 in pure ethanol. The ion pair is subject to electrostatic stabilization as manifested by a linear log Kassvs. (dielectric constant)–1 plot. This type of interaction would be stabilized in a hydrophobic environment, and may have a multiple role in enzymic processes requiring the thiamine pyrophosphate coenzyme.
Expression of a functional porcine growth hormone receptor cDNA in mouse L cells

Abstract Porcine (p) growth hormone receptor (GHR) complementary DNA (cDNA) has been cloned and the primary amino acid structure was deduced from the nucleotide sequence. A comparison of pGHR to other GHRs revealed an ~ 70% similarity in amino acid sequence (Cioffi et al., 1990). Hybridization of this receptor cDNA to RNA samples isolated from various porcine tissues revealed a single RNA band of 4.2 kb. The full-length pGHR cDNA was subcloned into an eukaryotic expression vector, transcription of which was directed by the mouse metallothionein-I transcriptional regulatory sequence. Stable mouse L cell lines which express the pGHR cDNA were established. Approximately 80% of the cell lines were found to possess pGHR mRNA (~ 2 kb) which corresponds to the length of the cloned pGHR cDNA. Binding studies showed that the stable cell lines were capable of specifically binding 125I-labeled pGH with a dissociation constant (Kd) of approximately 1.0 nM. The apparent molecular mass of the receptor, as determined by cross-linking studies, was found to be 118 kDa. Also, the receptor-ligand complex could be internalized. These results suggest that an active form of pGHR had been cloned and stably expressed in mouse L cells.
The Study of Gender in the Courts: Keeping Bias at Bay

I am pleased to introduce the following two companion papers on gender in the United States Eighth Circuit courts. They emerge from a partnership of social scientists and legal professionals, spurred by a national movement to understand influences of gender on the judicial system. These studies reflect a majority of voices in the Eighth Circuit bench and bar– women and men who work in and preside over the federal courts of seven states. This project yielded a wealth of data, the analysis of which reveals ways both subtle and overt by which gender bias threatens fairness in the courts. Underscoring the importance of this and similar projects, Supreme Court Justice Sandra Day O'Connor once stated, “by acknowledging and not trivializing the effects of gender bias on reasonable women and men, courts can work toward ensuring that neither men nor women will have to run a gauntlet of abuse in return for the privilege of being allowed to work and make a living” (as quoted in the Final Report of the Eighth Circuit Gender Fairness Task Force [ECGFTF] 1997, 8).
Mass transport in sub-2-μm high-performance liquid chromatography

Ultra-high pressure liquid chromatography enables increased separation speed and efficiency. The quantitative improvement in efficiency is lower than that predicted by theory, and the reasons are not known. In this work, slow mass transport due to analyte desorption from the stationary phase is discussed as a possible contribution to the lower than expected efficiency. Data in the literature for the reversed phase elution of acetophenone, for which particle size was varied with constant particle composition and mobile phase, were used to test this possibility. The mass transport terms for the three particles sizes (1.7, 3.5 and 5.0 microm) fit well to a model that includes desorption from the stationary phase as a contribution, and this analysis yields an apparent desorption time constant of 2.0(+/-0.2)ms for acetophenone in a reversed-phase separation. The results indicate that it is reasonable to consider slow desorption as a possible contribution to the reduced plate height for sub-2-microm particles.
Fate of the pulmonic valve after proximal pulmonary artery-to-ascending aorta anastomosis for aortic outflow obstruction

Abstract Transection of the main pulmonary artery and end-to-side anastomosis of the proximal pulmonary artery to the ascending aorta has been increasingly used in palliative surgery for cardiac malformations such as single ventricle with small outlet foramen (bulboventricular foramen) and hypoplastic left-heart syndrome. To evaluate pulmonary valve competence after this operation, we used color Doppler flow mapping to examine 45 survivors of pulmonary artery-to-ascending aorta anastomosis a median of 202 days postoperatively. Of 37 patients with hypoplastic left heart syndrome, mild regurgitation was detected in 9 (24%) and moderate regurgitation in 1 (3%). Of 8 with other lesions, mild regurgitation was observed in 2 and moderate regurgitation in 1. Seven of 11 patients imaged ≥ 12 months postoperatively had regurgitation. In summary, one-fourth of survivors developed mild pulmonary regurgitation. Its presence should not be considered a contraindication to eventual application of Fontan's principle, although further follow-up appears warranted because the long-term fate of pulmonary valve function is not yet known.
From Teachers to Students: What Influences Early Childhood Educators to Pursue College Education

Underpaid and overworked, preschool teachers face multiple barriers in pursuing higher education. In the present study, we explored how logistical and financial barriers hinder early childhood education teachers and teacher's aides from taking college courses, as well as how academic self-concept and social support influence current enrollment. Telephone interviews were conducted with 68 teachers and 38 teacher's aides currently employed by 85 child care centers in western Massachusetts. Results revealed that both structural and psychological factors are associated with teachers' and teacher's aides' enrollment in college. Financial and practical concerns, however, did not depress current enrollment once other factors were taken into account. Beliefs about education and motivation were critical for enrollment. Social support from parents may indirectly influence teachers' enrollment by increasing their motivation for college attendance. Younger teachers, African Americans, and those with friends in colleg...
Observations on the Sexual Behavior of New Hampshire Males

Abstract ALTHOUGH the physiology of reproduction of the female domestic fowl has been very, carefully studied by a large number of investigators, relatively mew studies have been made with the male. Important contributions have been made in this field by Hutt (1929), Penquite, Craft, and Thompson (1930), Burrows and Quinn (1937), Burrows and Titus (1939), Munro (1935, 1938, and 1938a), and most recently by Sampson and Warren (1939). The purpose of these investigations was to obtain information concerning the sexual activity and sperm production in the male domestic fowl. EXPERIMENTAL The data presented herein are based upon observations with New Hampshire males which were hatched early in the spring of 1938. Unless otherwise indicated, the semen was collected by means of a semen collector especially devised for use in the studies (Parker, 1939). The males were all given 36 hours of sexual rest before they were released into a small enclosure . . .
A novel non-linear ion mirror with only three elements

A novel tubular ion mirror has been designed for reflectron time-of-flight mass spectrometry (TOF-MS). This design consists of only three cylindrical elements. With this mirror, an electric field is achieved that is non-linear along the mirror axis and has improved offaxis homogeneity compared with conventional simple geometry ion mirrors. The practical operation of this mirror is simpler than that of conventional diaphragm ion mirrors. Design parameters, including the relative lengths and voltages of the three elements, can be determined empirically. Once the mirror depth dimensions have been implemented, the voltages of the middle and rear elements are the only adjustable parameters. The electric field achieved by the mirror deviates only slightly from a linear mirror with constant field strength. The second-order deviation curve reveals two regions of curvature; all ions are turned around in the second curvature region. A plot of arrival time vs ion kinetic energy has a flattened “S” shape. The aspects of this shape are affected by the voltages of the middle and rear elements. SIMION 7 simulation demonstrates that this new non-linear ion mirror can perform second-order kinetic energy correction for large kinetic energy variation (33%) and substantial beam dimensions. Both the ion kinetic energy variation and the mirror element voltages affect the mass resolution obtained with the mirror. Ion trajectory simulations with a 10 mm diameter beam from a standard, two-field source predict that baseline resolution can be 16,000, 7600 and 1200 for 15%, 26% and 33% kinetic energy variations, respectively.