cssi/SciSciGPT-SciSciNet huggingface dataset:
Differences in motivations of paid versus nonpaid volunteers.

Summary 143 AmeriCorps volunteers (30 men; 113 women) and 127 college student volunteers (43 men; 84 women) completed the Volunteer Functions Inventory to assess whether monetary compensation was associated with choice to volunteer to provide educational services, e.g., tutoring, mentoring. Based on Snyder's 1993 theory of functionalism, motives of paid (AmeriCorps participants) and nonpaid (college students) volunteers were expected to differ. It was also predicted that the motives of female and male volunteers would differ. Multivariate analysis of variance confirmed these assumptions. In general, paid male participants reported perceiving numerous benefits associated with volunteering and reported stronger beliefs about such benefits. Female participants reported motives for volunteering, in contrast, which were not linked with monetary compensation. The women reported recognizing the benefits of volunteering and engaging in this activity for egoistic reasons. Their reported motives had little relation...
Evaluation of culturing in endodontic therapy. A preliminary clinical report.

Abstract 1. 1. A preliminary clinical study of ninety-eight endodontic cases was completed in an effort to evaluate the use of a culturing technique in endodontic therapy. 2. 2. A greater degree of success in healing occurred when teeth were filled with no evidence of microorganisms in the root canals. 3. 3. A proper culturing technique should be used routinely by the dentist in order to obtain the most favorable prognosis possible for his patient.
Genetic control of acquired resistance to visceral leishmaniasis in mice.

A series ofH-2 and non-H-2 congenic resistant (CR) strains on a C57BL/10Sn background were infected with 107 amastigotes ofLeishmania donovani. Non-H-2 congenic strains B10.LP-H-3 b and B10.CE(30NX) and (B10.LP-H-3 b × B10)F1 hybrids showed a very rapid decrease in liver-parasite burdens beyond day 21. Parasite counts for these strains at day 35 were significantly lower than for all other strains tested. The rapid decrease in parasite numbers, massive lymphocellular infiltration into the liver and strong delayed hypersensitivity reactions to parasite antigens in strains congenic for a portion of chromosome 2 indicated that acquired immunity toL. donovani was controlled by a dominant gene at or near theIr-2 locus. In addition, B10.129(10M) mice, which differ from C57BL/10Sn at theH-11 locus, showed highly significant increases in parasite numbers at day 35. Other observations supporting the absence of acquired immunity in B10.129(10M) included negative delayed hypersensitivity tests to parasite antigens and the absence of lymphocellular infiltrate into the liver. Although the differences were not as pronounced,H-2 CR strains withH-2 b ,H-2 a , andH-2 k haplotypes also showed significantly greater decreases in parasite numbers by day 35 as compared to otherH-2 CR strains.
Elevated CO2 enhances biological contributions to elevation change in coastal wetlands by offsetting stressors associated with sea-level rise

1. Sea-level rise, one indirect consequence of increasing atmospheric CO 2 , poses a major challenge to long-term stability of coastal wetlands. An important question is whether direct effects of elevated CO 2 on the capacity of marsh plants to accrete organic material and to maintain surface elevations outweigh indirect negative effects of stressors associated with sea-level rise (salinity and flooding). 2. In this study, we used a mesocosm approach to examine potential direct and indirect effects of atmospheric CO 2 concentration, salinity and flooding on elevation change in a brackish marsh community dominated by a C 3 species, Schoenoplectus americanus, and a C 4 grass, Spartina patens. This experimental design permitted identification of mechanisms and their role in controlling elevation change, and the development of models that can be tested in the field. 3. To test hypotheses related to CO 2 and sea-level rise, we used conventional ANOVA procedures in conjunction with structural equation modelling (SEM). SEM explained 78% of the variability in elevation change and showed the direct, positive effect of S. americanus production on elevation. The SEM indicated that C 3 plant response was influenced by interactive effects between CO 2 and salinity on plant growth, not a direct CO 2 fertilization effect. Elevated CO 2 ameliorated negative effects of salinity on S. americanus and enhanced biomass contribution to elevation. 4. The positive relationship between S. americanus production and elevation change can be explained by shoot-base expansion under elevated CO 2 conditions, which led to vertical soil displacement. While the response of this species may differ under other environmental conditions, shoot-base expansion and the general contribution of C 3 plant production to elevation change may be an important mechanism contributing to soil expansion and elevation gain in other coastal wetlands. 5. Synthesis. Our results revealed previously unrecognized interactions and mechanisms contributing to marsh elevation change, including amelioration of salt stress by elevated CO 2 and the importance of plant production and shoot-base expansion for elevation gain. Identification of biological processes contributing to elevation change is an important first step in developing comprehensive models that permit more accurate predictions of whether coastal marshes will persist with continued sea-level rise or become submerged.
The impact of a high‐dependency unit on the workload of an intensive care unit

While there has been recent support for high-dependency unit development, there are few data reporting the impact of such development on existing critical care facilities. Therefore the aim of this study was to examine the workload and capacity constraints of an adult general intensive care unit before and after the development of an adjacent high-dependency unit. Following the opening of the high-dependency unit, the total number of patients admitted increased by 49%. On the high-dependency unit, more elderly patients were admitted for longer and more frequently following midweek elective surgery. On the intensive care unit, patients' initial severity of illness was lower and their duration of admission decreased; fewer patients were admitted directly from the general wards. The financial benefits of high dependency care may be eroded by the increased use of the critical care services.
Absolute two-photon cross section of Rb measured by differential absorption.

We applied a simple, sensitive differential absorption technique to measure the two-photon cross section for the 52S1/2(Fg = 2) → 52D5/2(F = 4) hyperfine transition in 85Rb [σ(2) = (1.2 ± 0.5) × 10−18 cm4/W]. The detection circuit permitted straightforward measurements close to the shot-noise limit. Detailed quantitative analysis of the measurements shows excellent agreement with theory.
Antiretroviral Therapy Reduces the Magnitude and T Cell Receptor Repertoire Diversity of HIV-Specific T Cell Responses without Changing T Cell Clonotype Dominance

After initiation of antiretroviral therapy (ART), HIV loads and frequencies of HIV epitope-specific immune responses decrease. A diverse virus-specific T cell receptor (TCR) repertoire allows the host to respond to viral epitope diversity, but the effect of antigen reduction as a result of ART on the TCR repertoire of epitope-specific CD8+ T cell populations has not been well defined. We determined the TCR repertoires of 14 HIV-specific CD8+ T cell responses from 8 HIV-positive individuals before and after initiation of ART. We used multiparameter flow cytometry to measure the distribution of memory T cell subsets and the surface expression of PD-1 on T cell populations and T cell clonotypes within epitope-specific responses from these individuals. Post-ART, we noted decreases in the frequency of circulating epitope-specific T cells (P = 0.02), decreases in the number of T-cell clonotypes found within epitope-specific T cell receptor repertoires (P = 0.024), and an overall reduction in the amino acid diversity within these responses (P < 0.0001). Despite this narrowing of the T cell response to HIV, the overall hierarchy of dominant T cell receptor clonotypes remained stable compared to that pre-ART. CD8+ T cells underwent redistributions in memory phenotypes and a reduction in CD38 and PD-1 expression post-ART. Despite extensive remodeling at the structural and phenotypic levels, PD-1 was expressed at higher levels on dominant clonotypes within epitope-specific responses before and after initiation of ART. These data suggest that the antigen burden may maintain TCR diversity and that dominant clonotypes are sensitive to antigen even after dramatic reductions after initiation of ART.
Analysis of ground-based and satellite observations of F-region behavior during the great magnetic storm of July 15, 2000

Abstract Ground-based and satellite data on the total electron content (TEC), ion density, and velocity are analyzed to determine the main processes forming the TEC enhancement at middle and low latitudes during the great magnetic storm of July 15, 2000. According to the model presented here, a southward neutral wind can provide the small TEC enhancement observed at middle latitudes during the daytime. However, a large TEC enhancement occurred at low latitudes in the evening sector after a sudden drop in D st and this enhancement can only be explained by the penetration of a strong electric field at middle and low latitudes. Using an eastward electric field of about 6 mV/m makes it possible to describe a very high TEC enhancement in the crest of the equatorial anomaly and a poleward displacement of the crest before sunset. Simultaneously, the model indicates a significant depletion in the equatorial trough. A very large value for the ratio of TEC (crest)/TEC (trough) is a result of these processes. One of the main features of the electron density height profiles calculated by the model under these conditions is a very high F 2 peak altitude. The analysis also leads to the conclusion that sunward convection of plasma must be taken into account to explain the spatial distribution of the TEC enhancement shown by GPS maps in the North American sector.
Self-schemata and processing information about the self.

Attempts to organize, summarize, or explain one's own behavior in a particular domain result in the formation of cognitive structures about the self or selfschemata. Self-schemata are cognitive generalizations about the self, derived from past experience, that organize and guide the processing of the self-related information contained in an individual's social experience. The role of schemata in processing information about the self is examined by linking self-schemata to a number of specific empirical referents. Female students with schemata in a particular domain and those without schemata are selected and their performance on a variety of cognitive tasks is compared. The results indicate that self-schemata facilitate the processing of information about the self (judgments and decisions about the self), contain easily retrievable behavioral evidence, provide a basis for the confident self-prediction of behavior on schema-related dimensions, and make individuals resistant to counterschematic information. The relationship of self-schemata to cross-situational consistency in behavior and the implications of self-schemata for attribution theory are discussed.
Cigarette Smoking as Part of a Syndemic among Young Men Who Have Sex with Men Ages 13–29 in New York City

The prevalence of cigarette smoking among young men who have sex with men (YMSM) is significantly higher than among their heterosexual peers. We undertook an analysis to examine cigarette smoking in relation to demographic factors and other risk behaviors among 580 YMSM, ages 13–29, in New York City. Cross-sectional data were collected as part of larger study of risk behaviors using palm devices and targeted active recruitment strategies across all five boroughs of the city. Multivariate modeling suggests that Asian or Pacific Islander and White YMSM are more likely to report cigarette smoking than other racial and ethnic groups, as are men reporting a middle class socioeconomic status. In addition, smoking was related to the likelihood of using a variety of illicit substances, as well as alcohol and pharmaceuticals without a prescription, during the period of assessment. YMSM who smoke cigarettes reported a greater number of casual sex partners and a greater number of transactional sex partners than non-smokers. Episodic analysis of sexual behaviors with casual partners indicated that smokers were more likely to engage in illicit drug and alcohol use immediately before or during sex than did non-smokers. These findings are understood as part of a larger syndemic among YMSM, and suggest that smoking prevention and cessation programs should be embedded as part of larger more holistic health and wellness programs targeting YMSM.
On the stability of the computation of the stationary probabilities of Markov chains using Perron complements

For an n-state ergodic homogeneous Markov chain whose transition matrix is T∈ℝn,n, it has been shown by Meyer on the one hand and by Kirkland, Neumann, and Xu on the other hand that the stationary distribution vector and that the mean first passage matrix, respectively, can be computed by a divide and conquer parallel method from the Perron complements of T. This is possible due to the facts, shown by Meyer, that the Perron complements of T are themselves transition matrices for finite ergodic homogeneous Markov chains with fewer states and that their stationary distribution vectors are multiples of the corresponding subvectors of the stationary distribution vector of the entire chain. Here we examine various questions concerning the stability of computing the stationary distribution vectors of the Perron complements and compare them with the stability of computing the stationary distribution vector for the entire chain. In particular, we obtain that condition numbers which are related to the coefficients of ergodicity improve as we pass from the entire chain to the chains associated with its Perron complements. Copyright © 2003 John Wiley & Sons, Ltd.
Creativity of undergraduates with and without family history of alcohol and other drug problems

Noble, Runco, and Ozkaragoz (1993) provided evidence that alcoholics' children differ negatively from recovering alcoholics' and nonalcoholics' children in terms of personality characteristics related to creativity. They also found that divergent thinking test scores among the three groups of children are similar, yet the possibility exists that offspring compensate for the personality deficits and maintain productively creative lives in spite of the negative influence of parental substance use. This study investigated the impact of parental substance abuse problems on 163 undergraduates' creative achievement. With current alcohol consumption as a covariate, analysis of covariance results suggest that parental alcohol and drug problems do not have an appreciable effect on students' creative achievement, although marginally significant interaction of gender and family history provides limited evidence that gender may influence the impact of parental substance abuse on creativity. Because the true effects of parental substance abuse may not be felt for several years, future research should investigate these issues with older offspring.
Cognitive biases in energy decisions during the planning, design, and construction of commercial buildings in the United States: an analytical framework and research needs

Despite a national goal for every building to achieve net-zero energy by 2050 and despite exemplary projects proving the technical and economic feasibility of much better energy performance, commercial buildings in the USA today use more energy per square foot than they ever have. Decisions made during planning, design, and construction (delivery) of commercial buildings appear systematically irrational, not maximizing utility for designers, occupants, or society. In other fields, notably economics, improved understanding of cognitive biases like “loss aversion” and “anchoring” has helped to explain seemingly irrational decision making. Related work has examined these cognitive biases for energy decisions made in an occupied building. Less clear is the role these cognitive biases play in the high-impact, long-term energy decisions made during commercial building delivery. As an initial step towards addressing this gap in understanding, this paper outlines key energy decisions in commercial building delivery and shows how cognitive biases may impact these decisions. A suggested approach to study these biases, and to design policies that address them, is provided. By highlighting these potential cognitive biases, based on an understanding of the building delivery process, this paper aims to engage those with relevant expertise in the behavioral and social sciences to help address the decision making that is preventing progress towards improved energy performance in commercial buildings.
Strong coefficient stability for quasilinear elliptic equations with application to inverse coefficient problems

In this paper an existence, uniqueness and coefficient convergence of the solution of nonlinear boundary value problems related to quasilinear elliptic operator is studied by assuming minimal conditions on the coefficient . By using the monotonicity method it is shown that the sequence of solutions of linearised problem converges to the solution of the nonlinear problem in HI-norm. The coefficient convergence theorem for the linearised problem is proved. Then the same result HI-norm is obtained for considered nonlinear problem.
Toward an optimal position for inferior vena cava filters: computational modeling of the impact of renal vein inflow with Celect and TrapEase filters.

Purpose To evaluate the hemodynamic effects of renal vein inflow and filter position on unoccluded and partially occluded inferior vena cava (IVC) filters with use of three-dimensional computational fluid dynamics. Materials and Methods Three-dimensional models of the TrapEase and Gunther Celect IVC filters, spherical thrombi, and an IVC with renal veins were constructed. Hemodynamics of steady-state flow was examined for unoccluded and partially occluded TrapEase and Gunther Celect IVC filters in varying proximity to the renal veins. Results Flow past the unoccluded filters demonstrated minimal disruption. Natural regions of stagnant/recirculating flow in the IVC were observed superior to the bilateral renal vein inflows. High flow velocities and elevated shear stresses were observed in the vicinity of renal inflow. Spherical thrombi induce stagnant/recirculating flow downstream of the thrombus. Placement of the TrapEase filter in the suprarenal position resulted in a large area of low shear stress/stagnant flow within the filter just downstream of thrombus trapped in the upstream trapping position. Conclusions Filter position with respect to renal vein inflow influences filter trapping hemodynamics. Placement of the TrapEase filter in a suprarenal location may be thrombogenic, with redundant areas of stagnant/recirculating flow and low shear stress along the caval wall caused by the upstream trapping position and the naturally occurring region of stagnant flow from the renal veins. Infrarenal vein placement of IVC filters in a near-juxtarenal position with the downstream cone near the renal vein inflow likely confers increased levels of mechanical lysis of trapped thrombi from increased shear stress from renal vein inflow.
All -Optical Smart Structure Based on Thin Film Chemical Sensor/Actuator

The design of two of the components which comprise a smart structure is described. A smart structure is a system that has a sensor, control, and actuator. The two aspects that are discussed are the sensor and actuator. There have been numerous changes made to the basic design of the smart structure components to improve their simplicity and cost efficiency. The novel design of the sensor of ammonia based on a planar optical waveguide made of thin fi lm of polymer polyimide doped with indicat or dye bromocresol purple is explained . This particular sensor is designed to detect the presence of ammonia in ambient air. The film of dye -doped polyimide demonstrated reversible increase of absorption with a pea k near 600 nm in response to presence of ammonia in ambient air. Two advantages of the polymer is that it works at elevated temperatures as high as 300 o C and it can be saturated with water vapor in such a way that our sensor will not be affected by the cha nge in humidity of ambient air. To improve the sensitivity of the sensor the concentration of dye dopant was increased. This gave more than a ten times better sensitivity (1 ppm) . The coupling of input and output optic fibers with the waveguide was done by means of coupling prisms or coupling grooves. The latter configuration has the advantage of low cost, less sensitivity to temperature variation, and the possibility of coupling from both sides of the waveguide . Exposing the sensor to more than 5000 ppm of ammonia led to saturation of the sensitive film which causes an increase in response time and a decrease in sensitivity. Also a description of an actuator that uses the principle of the photomechanical effect in polyvinylidene fluoride is detailed. To ach ieve the photothermal bending of strips of polyvinylidene fluoride a laser beam with a few milliwatts of power was used. The force generated by the bending strip of polymer was 10 -4 N, which propelled a 1 g oscillating wheel of a mechanical clock. The freq uency of photomechanical resonance at pulsed illumination was inversely proportional to the length of the strip.
Volterra series analysis of semiconductor optical amplifiers

Recently, semiconductor optical amplifiers (SOAs) have attracted much attention as potential candidates for active photonic circuits. In this paper, a Volterra series for the input-output map of such a device is derived using an existing nonlinear state space model. A second-order Volterra approximation is then compared in a specific instance against the full nonlinear model and a linearized model. It is shown that the Volterra model gives a more accurate estimate of gain and interchannel crosstalk than can a linearized model, especially when RMS power is used as the metric. The Volterra model is then employed to estimate the accuracy of the linearized model as a function of device length.
The Socialization of Highly Intelligent Boys: Case Material from Terman's Correspondence

Lewis M. Terman's letters to the parents of 42 boys with childhood IQs greater than 170 were examined and contrasted with those sent to parents of 42 boys with IQs between 135 and 159. Parents of boys with very high IQs were more frequently advised to restrain academic acceleration and to encourage mixing with agemates. The author places this advice in its historical context, suggests that the social needs of many highly intelligent children can best be satisfied in peer groups consisting of children of similar ability and interests, and concludes with a brief discussion of current options for jointly facilitating social and intellectual development.
Multiple Dimensions of Organizational Commitment: Implications for Future Accounting Research

Organizational commitment (OC) is a concept that seeks to capture the nature of the attachments formed by individuals to their employing organizations. Beginning with Porter et al. (1974), prior researchers have attempted to identify what factors influence the formation of OC in individuals and how OC (once formed) influences important organizational consequences. Recent research in the industrial/organizational psychology and organizational behavior literature has identified the existence of multiple dimensions of OC and found different relationships between these dimensions and important organizational consequences. However, with some isolated exceptions (Ketchand and Strawser 1998; Kalbers and Fogarty 1995; Caldwell et al. 1990), accounting research has examined only one dimension of OC. This manuscript summarizes previous research in the industrial/organizational psychology, organizational behavior, and particularly accounting literature regarding the identification of various dimensions and subdimens...
Effects of Variable Sources of Distillers Dried Grains Plus Solubles on Milk Yield and Composition

This study compared diets supplemented with distillers dried grains plus solubles originating from whiskey distilling with those from fuel alcohol production or soybean meal. Forty-eight cows in mid and early lactation were offered a different dietary treatment in each of three 28-d periods. Dietary design included three supplements at 14 or 18% CP of dietary DM, with or without blood meal. Additionally, a third, darker, fuel ethanol source was added at 14 and 18% CP without blood meal during period 3 to incorporate greater variation in quality of distillers grains. No detectable differences occurred in DMI or in any variables because of blood meal. Milk yield was higher when cows were fed diets at 18% rather than at 14% CP. Cows fed the two lighter distillers grains diets yielded .8 kg/d more milk than cows fed soybean meal diets, and cows fed whiskey distillers grains yielded 1.3 kg/d more SCM than cows fed diets with darkest distillers grains. Milk protein percentage was depressed when the darkest distillers grains were fed. Distillers dried grains plus solubles can provide an excellent substitute for soybean meal and corn in dairy cow diets.
Measurement of stem respiration of sycamore (Platanus occidentalis L.) trees involves internal and external fluxes of CO2 and possible transport of CO2 from roots

CO2 released by respiring cells in tree stems can either diffuse to the atmosphere or dissolve in xylem sap. In this study, the internal and external fluxes of CO2 released from respiring stems of five sycamore (Platanus occidentalis L.) trees were calculated. Mean rates of stem respiration were highest in mid-afternoon and lowest at night, and were positively correlated with air temperature. Over a 24 h period, on average 34% of the CO2 released by respiring cells in the measured stem segment remained within the tree. CO2 efflux to the atmosphere consisted of similar proportions of CO2 derived from local respiring cells (55%) and CO2 that had been transported in the xylem (45%), indicating that CO2 efflux does not accurately estimate respiration. A portion of the efflux of transported CO2 appeared to have originated in the root system. A modification of the method for calculating stem respiration based on internal and external fluxes of CO2 was developed to separate efflux due to local respiration from efflux of transported CO2.
Effects of Combined Water Potential and Temperature Stresses on Cryptosporidium parvum Oocysts

Volume 67, no. 12, p. 5526-5529, 2001. Page 5526, byline. The byline should read as shown above.
Holographic Probes of Anti-de Sitter Spacetimes

We describe probes of anti{endash}de Sitter spacetimes in terms of conformal field theories on the AdS boundary. Our basic tool is a formula that relates bulk and boundary states{emdash}classical bulk field configurations are dual to expectation values of operators on the boundary. At the quantum level we relate the operator expansions of bulk and boundary fields. Using our methods, we discuss the CFT description of local bulk probes including normalizable wave packets, fundamental and D-strings, and D-instantons. Radial motions of probes in the bulk spacetime are related to motions in scale on the boundary, demonstrating a scale-radius duality. We discuss the implications of these results for the holographic description of black hole horizons in the boundary field theory. {copyright} {ital 1999} {ital The American Physical Society}
Data exploitation of HyspIRI observations for precision vegetation mapping

An imaging spectrometer's dense recording of radiance values (and consequently derived reflectance values) over a wide region of the electromagnetic spectrum provides the potential to design classification systems that can perform highly accurate ground cover classification and target recognition. The Hyperspectral Infrared Imager (HyspIRI) — a National Research Council (NRC) decadal survey mission is much anticipated by researchers to aid in answering a wide variety of global ecological and anthropological questions. In order to tackle these research topics and effectively exploit the seasonal global imaging spectroscopy provided by HyspIRI, there will be a great need for reliable hyperspectral-based products for use by domain experts. In this work, we create simulated/proxy HyspIRI data from a database of hyperspectral signatures of various vegetation species. We then study the performance of current state-of-the-art pattern classification paradigms for classifying this proxy data. The outcome of this study will provide valuable insight into the potential efficacy of employing HyspIRI data for vegetation mapping and similar remotely sensed pattern classification tasks.
Remaking Men Men's Experiences Becoming and Being Husbands and Fathers and Their Implications for Reconceptualizing Men's Lives

Using findings from an exploratory interview study of 30 Boston area men, this article critically examines the traditional assumption that the male role centers on work. Findings indicated that becoming and being husbands and fathers had a greater effect on informants than conventional approaches suggest. Discontinuities between men's role attachments and performances are revealed, and the meaning and sociocultural sources of men's inaction are assessed.
The structure and reactivity of 2-butanol on Pd(1 1 1)

Abstract The structure, formation and decomposition pathways of 2-butoxide species formed on a Pd(1 1 1) surface following the adsorption of 2-butanol is studied by a combination of density functional theory (DFT), analysis of the low-energy electron intensity versus beam energy curves (LEED I/E) and temperature-programmed desorption (TPD). Both DFT calculations and LEED I/E measurements reveal that 2-butoxide adsorbs with the oxygen atom located in the three-fold hollow sites on Pd(1 1 1) with the C–O bond almost perpendicular to the surface with the 2-butyl group in the trans configuration. At coverages below ∼0.11 monolayers, adsorbed 2-butoxide species completely thermally decompose to desorb hydrogen and carbon monoxide. The 2-butoxide species present at higher coverages either hydrogenate to reform 2-butanol or undergo a β-hydride elimination reaction to form 2-butanone.
Induction of marginal zinc deficiency in female rhesus monkeys

Although severe zinc deficiency has been previously induced in rhesus monkeys, marginal zinc deprivation, a state more analogous to that found in human populations has not been characterized. To address this issue, zinc deficiency was induced in mature female rhesus monkeys by restriction of dietary zinc in a semipurified diet based on sprayed egg white as the protein source. Groups of monkeys were fed dietary levels of 0.5, 2, 4, 8, 12, 20, or 100 ppm zinc. Plasma zinc concentration fell from an initial level of 92–148 μg/100 ml to levels between 40 and 90 μg/100 ml in monkeys fed 8 ppm zinc or less. This reduction in plasma zinc concentration was associated with alterations in peripheral blood lymphocyte mitogen responsiveness, taste sensitivity, and behavior similar to those seen in human zinc deficiency. However, in contrast to studies of severe zinc deprivation, our animals did not manifest alopecia, dermatitis, anorexia, or weight loss. It was concluded that marginal dietary zinc deficiency can be readily produced in primates and that depressed zinc levels achieved by this selective dietary restriction can lead to quantitative physiological changes without overt pathology. These findings are important for the development of a relevant animal model of marginal zinc deficiency.
A Linear Alternative to Quadratic and Semivariance Programming for Farm Planning under Uncertainty

Quadratic decision criteria for farm planning are theoretically appealing but difficult to handle computationally. This paper reviews the advantages of the quadratic approach and develops a linear alternative which, while retaining most of the desired features of the quadratic models, can be readily solved on conventional linear programming codes with the parametric option.
Acceleration of Peritoneal Dialysis With Minimal N-myristyl-β-aminopropionate

A single short-term exposure of the peritoneal membrane to N-myristyl-β-aminopropionic acid solution (0.25%) gave an accelerating effect on the peritoneal clearance of salicylate, barbiturate, and diphenylhydantoin, which lasted throughout several subsequent exchanges with standard dialysis fluid. A brief kinetic study on N-myristyl-β-aminopropionate was done, and its intraperitoneal absorption and urinary and peritoneal clearances are reported. The LD50 of this wetting agent in mice and its hemolytic threshold were also estimated.
The Landsat Scale Break in Stratocumulus as a Three-Dimensional Radiative Transfer Effect: Implications for Cloud Remote Sensing

Several studies have uncovered a break in the scaling properties of Landsat cloud scenes at nonabsorbing wavelengths. For scales greater than 200‐400 m, the wavenumber spectrum is approximately power law in k25/3, but from there down to the smallest observable scales (50‐100 m) follows another k2b law with b . 3. This implies very smooth radiance fields. The authors reexamine the empirical evidence for this scale break and explain it using fractal cloud models, Monte Carlo simulations, and a Green function approach to multiple scattering theory. In particular, the authors define the ‘‘radiative smoothing scale’’ and relate it to the characteristic scale of horizontal photon transport. The scale break was originally thought to occur at a scale commensurate with either the geometrical thickness Dz of the cloud, or with the ‘‘transport’’ mean free path lt 5 [(1 2 g)s]21, which incorporates the effect of forward scattering (s is extinction and g the asymmetry factor of the phase function). The smoothing scale is found to be approximately ltDz at cloud top; this is the prediction of diffusion ˇ theory which applies when (1 2 g)t 5D z / l t * 1( tis optical thickness). Since the scale break is a tangible effect of net horizontal radiative fluxes excited by the fluctuations of t, the smoothing scale sets an absolute lower bound on the range where one can neglect these fluxes and use plane-parallel theory locally, even for stratiform clouds. In particular, this constrains the retrieval of cloud properties from remotely sensed data. Finally, the characterization of horizontal photon transport suggests a new lidar technique for joint measurements of optical and geometrical thicknesses at about 0.5-km resolution.
Managers’ Personal Political Orientation and Corporate Tax Avoidance

This study investigates whether managers’ personal political orientation helps explain tax avoidance at the firms they manage. Results reveal the intriguing finding that, on average, firms with top executives who lean toward the Republican Party actually engage in less tax avoidance than firms whose executives lean toward the Democratic Party. These findings are consistent with the argument that Republican managers’ preference for lower taxes is dominated by their desire to be conservative. Thus, the conservative tone at the top they set leads the firm to engage in less tax avoidance than firms that are run by Democrat managers. Additionally, we find that this effect appears to be driven by the subset of managers who are entrenched, which is consistent with managers having more freedom to imprint their personal preferences on firms with weaker governance. We also examine changes in tax avoidance around CEO turnovers and find corroborating evidence.
A Cloze-Based Investigation of Reading Comprehension as a Composite of Subskills.

Examination of validity studies related to the cloze procedure and reading comprehension revealed that researchers have not considered the relationship of cloze to comprehension subskills purportedly tapped by a standardized test of reading achievement. Cloze passages used in correlation studies were drawn from material other than the passages used in the standardized tests. Cloze tests derived from passages in the standardized reading test used as the criterion would seem to add greater content validity to correlation findings. This procedure would insure identical passage difficulty, content, length, and language structure. Since Bormuth (1967, 1968) and Raskin and Culhane (1968) have provided a precedent in the use of identical passages for cloze and multiple choice tests to establish concurrent validity, basing cloze tests on passages in standardized tests of reading achievement seems a logical extension of that concurrent validity procedure. Bormuth (1969) provided evidence that the cloze procedure does measure a factor identified as reading comprehension. Authors such as Davis (1972), Smith and Barrett (1974), Stroud (1969), and Lennon (1969) maintain that reading comprehension should be considered a composite of various subskills. Farr (1969), in a review of measurements in reading, concludes that even though validation of these subskills has not been successful, it is likely they do exist and should be accounted for in a measure of reading comprehension. The Davis Reading Test Form 2A was chosen for the criterion test. The cloze tests were constructed from the first, third, and fifth passages of the Davis Heading Test Form 2A (DRT). These tests were based on an every fifth word deletion; the first and last sentences of each passage were left intact. Following Bormuth's (1965) recommendations, it was determined that the three passages would account for the readability of the test with a minimum amount of error in measurement. In addition, since the researchers were not concerned with speed of comprehension, the cloze tests were limited to the section assessing level of comprehension. Davis designed each item of the DRT to assess the comprehension subskill he believed it to represent. The five subskills of comprehension in the DRT, identified in previous research by Davis (1944), are: 1. Finding the answers to questions answered explicitly or in paraphrase in a passage; 2. Weaving together the ideas in a passage and grasping its central thought; 3. Making inferences about the content of a passage and about the purpose or point of view of its author; 4. Recognizing the tone and mood of a passage and the literary devices used by its author; 5. Following the structure of a passage.
Measured equation of invariance: a new concept in field computations

Numerical computations of frequency domain field problems or elliptical partial differential equations may be based on differential equations or integral equations. The new concept of field computation presented in this paper is based on the postulate of the existence of linear equations of the discretized nodal values of the fields, different from the conventional equations, but leading to the same solutions. The postulated equations are local and invariant to excitation. It is shown how the equations can be determined by a sequence of "measures". The measured equations are particularly useful at the mesh boundary, where the finite difference methods fail. The measured equations do not assume the physical condition of absorption, so they are also applicable to concave boundaries. Using the measured equations, one can terminate the finite difference mesh very close to the physical boundary and still obtain robust solutions. It will definitely make a great impact on the way one applies finite difference and finite element methods in many problems. Computational results using the measured equations of invariance in two and three dimensions are presented. >
Security in the IEEE Mass Storage System Reference Model

The author discusses the origins of the distribution topology of the IEEE Mass Storage System Reference Model, how it affects security, and the methods that can be used to provide secure resource access. He also shows how certain security considerations emphasize the importance of particular Model-defined services and impose architectural constraints on those services. It is noted that the model's security problems stem from the client-centric distribution of various Model functions. These problems are heightened in Version 5 of the Model, in which any Model component is allowed to be distributed in a client-centric manner. While a distributed security scheme can provide an appropriate security environment, the relationships between Model components must be fully defined before any particular scheme can be recommended. Furthermore, it is critical that the correct authorization agents be identified with security, usability, and performance in mind. It is clear that, in certain cases, the Name Server becomes an important, if not focal, authorization agent. The challenge is to define a security protocol appropriate to the Model, as opposed to modifying the Model to fit current security schemes. >
Transcytosis and brain uptake of transferrin-containing nanoparticles by tuning avidity to transferrin receptor

Receptor-mediated transcytosis across the blood–brain barrier (BBB) may be a useful way to transport therapeutics into the brain. Here we report that transferrin (Tf)-containing gold nanoparticles can reach the brain parenchyma from systemic administration in mice through a receptor-mediated transcytosis pathway. This transport is aided by tuning the nanoparticle avidity to Tf receptor (TfR), which is correlated with nanoparticle size and total amount of Tf decorating the nanoparticle surface. Nanoparticles of both 45 nm and 80 nm diameter reach the brain parenchyma, and their accumulation there (visualized by silver enhancement light microscopy in combination with transmission electron microscopy imaging) is observed to be dependent on Tf content (avidity); nanoparticles with large amounts of Tf remain strongly attached to brain endothelial cells, whereas those with less Tf are capable of both interacting with TfR on the luminal side of the BBB and detaching from TfR on the brain side of the BBB. The requirement of proper avidity for nanoparticles to reach the brain parenchyma is consistent with recent behavior observed with transcytosing antibodies that bind to TfR.
Serum 25-hydroxyvitamin D and change in estimated glomerular filtration rate.

Summary Background and objectives Mounting evidence suggests that 1,25-dihydroxyvitamin D prevents the progression of chronic kidney disease (CKD). It is not clear whether “nutritional” forms of vitamin D affect GFR. Design, setting, participants, & measurements We tested whether serum 25-hydroxyvitamin D concentration (25(OH)D), a measure of total vitamin D intake from cutaneous synthesis and dietary consumption, is associated with loss of estimated GFR among 1705 older adults with predominantly normal baseline kidney function participating in the Cardiovascular Health Study. Baseline 25(OH)D was measured by HPLC-tandem mass spectrometry. GFR was estimated at baseline and 4 years later using the CKD-EPI formula, with rapid GFR loss defined as 12 ml/min per 1.73 m 2 or more over 4 years. Results Rapid GFR loss was observed for 207 participants (12%). Each 10 ng/ml lower 25(OH)D was associated with a 25% greater risk of rapid GFR loss (95% confidence interval [CI] 5%, 49%, P 0.01), adjusting for potential confounding characteristics. Compared with 25(OH)D 30 ng/ml, 25(OH)D concentrations 15 to 29 ng/ml and 15 ng/ml were associated with 29% (95% CI 13%, 91%) and 68% (95% CI 1%, 177%) greater adjusted risks of rapid GFR loss, respectively. Magnitudes of association were largest among participants with diabetes. Results were similar evaluating a composite outcome of rapid GFR loss, end stage renal disease, and death. Conclusions Insufficient 25(OH)D may be a modifiable risk factor for early GFR loss. We recommend clinical trials to determine whether vitamin D supplementation prevents the development and progression of CKD.
Microcirculatory dysfunction in ST-elevation myocardial infarction : cause, consequence, or both?

Aims Despite advancements over the past years, normal reperfusion at the myocardial level is not achieved in approximately every other patient with ST-elevation myocardial infarction. In the current work, we aimed at reviewing the role of the coronary microcirculation in the development and outcome of this acute coronary syndrome entity. Methods and results A PubMed/Medline search was performed with the key words acute coronary syndrome, acute myocardial infarction, coronary artery disease, endothelial dysfunction, microcirculation, and reperfusion. The synthesis of the information points to myocardial microcirculatory dysfunction as a consequence of a primary epicardial event, based on the vulnerable plaque concept. As an alternative theory, microcirculatory dysfunction may contribute to the clinical course of the acute coronary event, based on the vulnerable patient concept. The pros and cons of these two viewpoints are to be discussed and their influence on patient management is to be considered. Conclusion Microcirculatory dysfunction in ST-elevation myocardial infarction can be cause, consequence or both according to non-traditional and traditional concepts.
A strategy for oligonucleotide microarray probe reduction

Background One of the factors limiting the number of genes that can be analyzed on high-density oligonucleotide arrays is that each transcript is probed by multiple oligonucleotide probes. To reduce the number of probes required for each gene, a systematic approach to choosing the most representative probes is needed. A method is presented for reducing the number of probes per gene while maximizing the fidelity to the original array design.
Guidelines governing the need for low-impedance drivers for MCM's

High-speed, large-area integrated circuits (ICs) require packages with high-density, small cross-sectional interconnections. This trend toward more resistive interconnections is particularly clear for advanced thin-film multichip modules (MCMs). To obtain high clock speeds with these ICs and these packages requires a combined design of drivers, lines, and loads. By extending traditional impedance-matched design to a generalization that adjusts load, line, and driver for overshoot-controlled performance, maximum line lengths and driver impedances are found beyond which underdamped (i.e., rapid) response is not possible. These limits are provided for on-chip, MCM, and printed-circuit-board (PCB) interconnections. For line lengths typical of advanced thin-film MCM interconnections, an underdamped circuit response requires a driver with impedance significantly less than the characteristic impedance of a lossless interconnection line of the same geometry. As a result, drivers are required with impedances below the normal impedance-matched condition. Alternatively, wiring cross-sections can be increased with a corresponding decrease in wiring density or an increase in the number of wiring layers. >
Cell cycle: Cull and destroy

A newly discovered family of proteins homologous to yeast Cdc53, called cullins, may play a key role in the targeting of cell-cycle regulators, such as cyclins, for destruction by ubiquitin-dependent proteolysis.