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Accounting for within-species variability in the relationship between occurrence and climate is essential to forecasting species’ responses to climate change. Few climate-vulnerability assessments explicitly consider intraspecific variation, and those that do typically assume that variability is best explained by genetic affinity. Here, we evaluate how well heterogeneity in responses to climate by a cold-adapted mammal, the American pika (Ochotona princeps), aligns with subdivisions of the geographic range by phylogenetic lineage, physiography, elevation or ecoregion. We find that variability in climate responses is most consistently explained by an ecoregional subdivision paired with background sites selected from a broad spatial extent indicative of long-term (millennial-scale) responses to climate. Our work challenges the common assumption that intraspecific variation in climate responses aligns with genetic affinity. Accounting for the appropriate context and scale of heterogeneity in species’ responses to climate will be critical for informing climate-adaptation management strategies at the local (spatial) extents at which such actions are typically implemented. Intraspecies response to climate change is expected to align with genetic affinity. Using the American pika as a case study suggests that divisions of species distributions best explain intraspecific heterogeneity in climate relationships.

We explore the role of social networks used by people with disabilities for finding employment. In addition, we outline obstacles to network building for those with a disability. We contend that this group is often constrained and they underutilize their networks during job searches. Both factors are likely to result in negative employment outcomes and contribute to the employment gap between those with and without a disability. We outline how key network characteristics such as homophily, tie strength, and centrality influence job search outcomes for those with a disability differently than for those without a disability. Furthermore, we propose that although individuals with disabilities develop and rely upon networks that are comprised of close bonds with similar individuals that are either unemployed or underemployed in lower status positions, optimal networks for employment purposes should consist of diverse acquaintances that occupy central positions and higher status jobs within organizations. Finally, we outline propositions to guide future research on this neglected topic and also suggest practical implications.

Keeping or losing the best workers can be critical to whether an organization can maintain a competitive advantage and whether operations in the organization run smoothly and efficiently. Simply stated, if the best workers are not retained, an organization can be negatively affected from the operational to the strategic level. This article focuses on employee retention from the perspective of a customer-based model. This approach considers employees as internal customers of management and the model provides organizations ways to influence whether employees decide to stay or go. Additionally, the model distinguishes retention practices based upon the value of employees to the organization. Measurement and application issues are identified along with directions for future research.

The relative effects of nutrients and herbivores on primary producers are rarely compared across ecosystems that vary in potential primary productivity. Furthermore, proposed mechanisms to explain such patterns remain understudied. Here, I examine the strength of nutrient and grazer (herbivore) limitation (i.e., the extent to which producers’ growth is limited by insufficient nutrient supply or herbivory) of benthic algae across 13 southwest Michigan lakes that vary widely in productivity (i.e., resource supply). I compare the observed patterns of algal limitation and species composition to those predicted by two simple models: one that includes multiple species and species’ traits (the food-web model) and one that includes no variation in species or traits (the food-chain model). Species in the food-web model are assumed to display a tradeoff between resource competitive ability and resistance to herbivory (the “keystone predator” tradeoff). Among these lakes, benthic algal nutrient limitation was positive $$ {\left( {\ifmmode\expandafter\bar\else\expandafter\=\fi{x} = 0.083\,{\text{day}}^{{ - 1}} } \right)} $$ and declined significantly along a lake N:P gradient. In contrast, grazer limitation was negative $$ {\left( {\ifmmode\expandafter\bar\else\expandafter\=\fi{x} = - 0.019\,{\text{day}}^{{ - 1}} } \right)} $$ and was not significantly related to any of the measured lake productivity variables. Negative grazer limitation indicated that the removal of grazers caused unexpected declines in algal biomass, which were potentially due to indirect, positive effects (e.g., nutrient recycling) of grazers. Nutrient limitation was significantly stronger than grazer limitation across lakes, which was more consistent with the food-web versus food-chain model. Changes in algal composition were also broadly consistent with predictions of the food-web model in that vulnerable, superior nutrient competitors dominated in low productivity lakes and more grazer-resistant species were observed in high productivity lakes. In general, these results point to the importance of examining limiting factors across systems and the consideration of key species’ traits when predicting and interpreting patterns.

I be Unman Resourees (HR) function has always been on tbe I'orefnMit of integrating teehnology in organi/ations. In faet, one ofthe earliest business pr-oeesses to be atrtiimated in organi/ations was payroll administration. Since tben. HR has eontinned to merge new tecbnology with okl processes. For example, most organi/ations use eonipnters to ntaiittain their employee reeords. These hnman resotiree inlbrmation systems (HRIS) increase administrative eftlcieney and pr-oduce reports that have the potential to improve decision making.

The binding of beta-lactams to human serum proteins was modeled with topological descriptors of molecular structure. Experimental data was the concentration of protein-bound drug expressed as a percent of the total plasma concentration (percent fraction bound, PFB) for 87 penicillins and for 115 β-lactams. The electrotopological state indices (E-State) and the molecular connectivity chi indices were found to be the basis of two satisfactory models. A data set of 74 penicillins from a drug design series was successfully modeled with statistics: r2=0.80, s = 12.1, q2=0.76, spress=13.4. This model was then used to predict protein binding (PFB) for 13 commercial penicillins, resulting in a very good mean absolute error, MAE = 12.7 and correlation coefficient, q2=0.84. A group of 28 cephalosporins were combined with the penicillin data to create a dataset of 115 beta-lactams that was successfully modeled: r2=0.82, s = 12.7, q2=0.78, spress=13.7. A ten-fold 10% leave-group-out (LGO) cross-validation procedure was implemented, leading to very good statistics: MAE = 10.9, spress=14.0, q2 (or r2 press)=0.78. The models indicate a combination of general and specific structure features that are important for estimating protein binding in this class of antibiotics. For the β-lactams, significant factors that increase binding are presence and electron accessibility of aromatic rings, halogens, methylene groups, and =N– atoms. Significant negative influence on binding comes from amine groups and carbonyl oxygen atoms.

The soil microbial population of a coke oven site was investigated in order to evaluate its potential for bioremediation. The study was carried out in soil samples with distinct polynuclear aromatic hydrocarbon (PAH) contamination levels, comparing the population profiles constituted by total heterotrophic and PAH-utilizing strains. Isolation of degrading strains was performed with phenanthrene or pyrene as sole carbon sources. The ability to degrade other PAHs, such as anthracene, fluorene and fluoranthene was also investigated. The results showed a reduction of 30% in species diversity and microbial density drops one order of magnitude in contaminated samples. Furthermore, the number of PAH-utilizing colonies was higher in the contaminated area and about 20% of the isolates were able to degrade phenanthrene and pyrene, while this value decreased to 0.15% in uncontaminated samples. Three PAH-degrader strains were identified as: CDC gr. IV C-2, Aeromonas sp. and Pseudomonas vesicularis. The ability of these strains to degrade other PAHs was also investigated.

The etiology and pathogenesis of idiopathic interstitial lung disease (ILD) remain incompletely understood. Genetic susceptibility to ILD has been demonstrated in previous studies. It is well known that EGFR inhibitors can induce ILD in human lung cancer patient with ethnic differences, which prompted us to hypothesize that genetic variation in EGFR pathway genes confer susceptibility to ILD. We aimed in this study to investigate whether functional polymorphisms of EGFR and its ligands genes (EGF and TGFA) were associated with ILD. Three EGFR [−216G/T (rs712830), −191A/C (rs712829), 497R > K(A/G) (rs2227983)], one EGF [61A/G, (rs4444903)] and one TGFA (rs3821262C/T) polymorphisms previously demonstrated to alter gene functions were genotyped in 229 sporadic idiopathic ILD patients and 693 normal healthy individuals. Allelic and genotypic association tests between these polymorphisms and ILD were performed. The EGF 61A/G polymorphism was significantly associated with elevated risk of ILD, with the frequency of G allele significantly increased in the ILD patient population (OR = 1.33, 95%CI = 1.07–1.66, P = 0.0099). None of the other polymorphisms were associated with risk of ILD. Our study suggested that the EGF 61A/G polymorphism may be associated with sporadic ILD. While a false positive finding cannot be excluded, independent studies are warranted to further validate this result.

A logistic growth equation is used to model Mexico's epidemiological and fertility transitions, creating variables used to model the spatial diffusion of demographic change across the states. Consistent with the goals of the Lazaro Cardenas administration, the epidemiological transition unfolded uniformly across the states, accessible to rich and poor alike, but the urban-oriented family planning programs introduced by Luis Echeverria have favored elites, have diffused selectively, and have ensured that the burdens of the population explosion have borne down most heavily on the poor and the remote.

Quantitative assessments of potential human-health consequences from contaminants in environmental media routinely involve conservative deterministic, screening-level calculations of exposure and risk. Because these calculations generally are based on multiple upper-bound point estimates of input parameters, particularly for exposure attributes, they can yield results for decision makers that actually overstate the need for costly remediation. Alternatively, quantifying uncertainty and variability in exposure can provide a more informative and quantitative characterization of health risk. To illustrate, uncertainty and variability in exposure were analyzed for a hypothetical population at a specific site in California where there is trichloroethylene (TCE) contaminated ground water and a potential for its residential use. When uncertainty and variability in exposure were addressed jointly, the 95th-percentile upper-bound value of individual excess lifetime cancer risk was a factor approaching 10 lower than the most conservative deterministic estimate. Also, the probability of more than zero additional cases of cancer can be estimated, and in this case study it is less than 0.5 for a prospective residential population of up to 26,900 individuals present for any 7.6-y interval of a 70-y time period. Clearly, this probabilistic approach can provide reasonable and equitable risk-acceptability criteria for contaminated sites.

Background The major obstacles to the successful use of individual nutritional compounds as preventive or therapeutic agents are their efficacy and bioavailability. One approach to overcoming this problem is to use combinations of nutrients to induce synergistic effects. The objective of this research was to investigate the synergistic effects of two dietary components: docosahexaenoic acid (DHA), an omega-3 fatty acid present in cold-water fish, and curcumin (CCM), an herbal nutrient present in turmeric, in an in vivo model of DMBA-induced mammary tumorigenesis in mice. Methods We used the carcinogen DMBA to induce breast tumors in SENCAR mice on control, CCM, DHA, or DHA + CCM diets. Appearance and tumor progression were monitored daily. The tumors were harvested 15 days following their first appearance for morphological and immunohistological analysis. Western analysis was performed to determine expression of maspin and survivin in the tumor tissues. Characterization of tumor growth was analyzed using appropriate statistical methods. Otherwise all other results are reported as mean ± SD and analyzed with one-way ANOVA and Tukey’s post hoc procedure. Results Analysis of gene microarray data indicates that combined treatment with DHA + CCM altered the profile of “PAM50” genes in the SK-BR-3 cell line from an ER-/Her-2+ to that resembling a “normal-like” phenotype. The in vivo studies demonstrated that DHA + CCM treatment reduced the incidence of breast tumors, delayed tumor initiation, and reduced progression of tumor growth. Dietary treatment had no effect on breast size development, but tumors from mice on a control diet (untreated) were less differentiated than tumors from mice fed CCM or DHA + CCM diets. The synergistic effects also led to increased expression of the pro-apoptotic protein, maspin, but reduced expression of the anti-apoptotic protein, survivin. Conclusions The SK-BR-3 cells and DMBA-induced tumors, both with an ER- and Her-2+ phenotype, were affected by the synergistic interaction of DHA and CCM. This suggests that the specific breast cancer phenotype is an important factor for predicting efficacy of these nutraceuticals. The combination of DHA and CCM is potentially a dietary supplemental treatment for some breast cancers, likely dependent upon the molecular phenotype of the cancer.

Increasingly employers are testing employees for illicit drug use. Employees vary in their degree of acceptance of drug-testing policies. Both job and individual characteristics are hypothesized to affect individuals’ reactions to drug-testing policies. The first study reported here investigated the effect of job impact, job interdependence, sex, and age on four aspects of the acceptability of a drug-testing policy. While there was no effect for the job characteristics, both age and sex had significant effects. A follow-up study which focused solely on employee characteristics replicated the age effect. Implications are discussed.

Much of the current research on participative decision making focuses on the increasing need for broad-based decision-making systems, on the different outcomes associated with different forms of participation, or on the problems associated with poorly managed participative decision-making systems. This article considers the responsibilities of employees who participate in organizational decision making and the responsibilities of employers who expect to share decision-making tasks. A “Bill of Responsibilities for Employees” and a “Bill of Responsibilities for Employers” are presented. Pitfalls associated with neglecting these responsibilities are discussed.

Sixteen plasmid profile types have been identified in drug-sensitive isolates of Salmonella berta isolated from humans and human food in England and Wales in the ten-year period 1981-1990. Since 1988 six profile types of epidemiological importance have caused infections in widely-separated geographical areas and of these, four types have been identified in S. berta isolated from chicken carcasses imported from Denmark. The findings suggest that imported Danish poultry has substantially contributed to a recent upsurge of S. berta in humans in England and Wales.

Molecular dynamics simulations of C1 through C14 n-alkanes have been used to elucidate diffusion mechanisms in siliceous faujasite zeolites. Additional simulations of the bulk liquids were conducted to compare the liquid and adsorbed phases. Macroscopic quantities, such as heats of adsorption, diffusivities, and activation energies, were calculated and compare well with experimental values. In addition, the simulations provide detailed information about the mechanisms of alkane diffusion in the confined pores of faujasite.

The enzyme guanosine triphosphate cyclohydrolase (GTP cyclohydrolase), which in bacteria is known to be the first enzyme in the biosynthetic pathway for the synthesis of pteridines, has been discovered in extracts of Drosophila melanogaster. Most of the enzyme (80%) is located in the head of the adult fly. An analysis of enzyme activity during development in Drosophila has revealed the presence of a relatively small peak of activity at pupariation and a much larger peak that appears at about the time of eclosion. Enzyme activity declines rapidly as the fly ages. Analyses for the production of the typical pteridine pigments of Drosophila have indicated that the small peak of GTP cyclohydrolase activity evident at pupariation coincides with the appearance of isoxanthopterin, sepiapterin, and pterin, and the larger peak at eclosion roughly corresponds to the accumulation of drosopterin as well as to the appearance in larger amounts of pterin and sepiapterin. These observations strongly suggest that in Drosophila, like bacteria, GTP cyclohydrolase is involved in the biosynthesis of pteridines. Analyses of a variety of zeste mutants of Drosophila melanogaster have shown that these mutants all contain GTP cyclohydrolase equal approximately to the amount found in the wild-type fly. These observations do not support the suggestions made by Rasmusson et al. (1973) that zeste is the structural locus for GTP cyclohydrolase.

Samples derived from farm livestock, an abattoir and a bone factory, were examined for salmonella. Twenty-seven serotypes were detected in 130 infected samples. A bone factory product was heavily infected. Salmonellosis is considered to be an important disease of dromedary calves and poultry in Ethiopia.

Diflunisal is long-acting salicylate derivative. We examined the effect of single concomitant doses of three antacids on diflunisal bioavailability under fasting or fed conditions (30 min after finishing a standard meal). With the use of an open, randomized, and balanced design, one 250-mg diflunisal tablet was given to each of 12 healthy men under six conditions: fasted, no antacid; fed, no antacid; fasted, 15 ml of aluminum hydroxide gel; fed, 15 ml of aluminum hydroxide gel; fasted, 10 ml magnesium hydroxide suspension; and fed, 15 ml of an aluminum hydroxide/magnesium hydroxide mixture. Diflunisal plasma 0- to 48-hr area uiven to each of 12 healthy men under six conditions: fasted, no antacid; fed, no antacid; fasted, 15 ml of aluminum hydroxide gel; fed, 15 ml of aluminum hydroxide gel; fasted, 10 ml magnesium hydroxide suspension; and fed, 15 ml of an aluminum hydroxide/magnesium hydroxide mixture. Diflunisal plasma 0- to 48-hr area uiven to each of 12 healthy men under six conditions: fasted, no antacid; fed, no antacid; fasted, 15 ml of aluminum hydroxide gel; fed, 15 ml of aluminum hydroxide gel; fasted, 10 ml magnesium hydroxide suspension; and fed, 15 ml of an aluminum hydroxide/magnesium hydroxide mixture. Diflunisal plasma 0- to 48-hr area under the time curve (AUC), peak plasma concentrations, and 0-to 96-hr urinary excretion were determined. Food (alone) decreased peak plasma concentrations by 16% (P less than 0.05) but did not affect AUC or urinary excretion. Under fasting conditions, aluminum hydroxide reduced AUC by 26% (P less than 0.01), peak plasma concentrations by 46% (P less than 0.01), and urinary excretion by 14% (P less than 0.05). Magenisuum hydroxide suspension (in the fasting state) increased the early plasma concentrations (by 130% at 0.5 hr and 64% at 1 hr, P less than 0.05) and increased AUC by 10% (P less than 0.05) but had no effect on urinary excretion. In the fed state neither aluminum hydroxide nor the aluminum hydroxide/magnesium hydroxide mixture had any detectable effect.

An approximate stress intensity factor is derived for an embedded elliptical crack in a plate which is subjected to uniaxial tension in the direction perpendicular to the crack surface. The major axis of an eccentrically located elliptical crack is assumed to be parallel with the two plate surfaces. The approximate stress intensity factors on the minor axis of the elliptical crack are then determined as αBσ√a√π where a is a correction factor due to the curvature of the ellipse and 6 is a correction factor due to the eccentricity of the crack in the wall.

The diffusion of lead and of trace amounts of bismuth in liquid lead have been investigated by the capillary method, using RaD and RaF as tracers. The results are compared with existing theories of diffusion in liquids, the agreement with theory being fair. The heat of activation for self-diffusion in lead is found experimentally to be close to the corresponding activation energy obtained from viscosity data. The pioneer data of Groh and von Hevesi for the self-diffusion of liquid lead, using ThB as a tracer, fit in with the present results.

Scanning spectrometer measurements in the range 1310–270 A, observed from the satellite OSO 3, are reported for the solar flare of 2114 UT March 27, 1967. This flare was a long lasting sequence of bursts with EUV spectra consisting of enhanced lines and recombination continua normally emitted from the chromosphere and chromosphere-corona transition region, with unusually small increases in lines normally emited from the corona. An EUV flare spectrum is presented and suggested as one example for interpreting broadband observations of EUV bursts. Any broadband continuum other than known recombination continua contributed less than 6 % of the meassured line and hydrogen recombination continua in the range 270–1310 A. The ratio of photon flux of Ciii 1176 A to that of Ciii 977 A was 0.86, which suggests an ambient density in the region of emission greater than 1012 cm-3 at temperatures near 60000 K.

Solar electromagnetic radiation of wavelengths ranging from 260–1300 A was measured by a grazing-incidence grating spectrometer on OSO-III, which operated as a monochromator with a wavelength bandwidth of about 2 A and an acceptance angle covering the whole disk without any instrumental discrimination of source locations. The monochromator was commanded either to scan the whole spectrum or to operate at variously chosen fixed wavelengths. The latter mode of operation afforded a high-time resolution in the observation of temporal variations such as those associated with solar flares, and also allowed accurate determinations of the absorption characteristic of the earth's upper atmosphere (near sunset and sunrise).

Wave functions and energies are calculated for cyclopentadiene, cyclopentadienone, and maleic anhydride under the LCAO-MO approximation with a basis set of atomic orbitals which is comprised of all valence electrons. The geometries of the molecules, required as inputs to the MO calculations, are determined with a procedure which minimizes the ring angular deformation energy. The various possible Diels-Alder reactions of these compounds are then considered. Second-order perturbation theory, with variable overlap integrals and including all interactions, is used to estimate the energies of transition intermediates or states which correspond closely to π complexes. Predicted endo-exo isomeric adduct ratios are in agreement with experimentally known values. Predictions of the relative rates for Diels-Alder reactions reflect the correct order and magnitude of reactivity, where experimental results are known.

Measurements of flare-related impulsive enhancements in solar emission lines in the extreme ultraviolet, observed from the satellite OSO-III, are reported. The enhancement of a line, expressed in percent of the total disk intensity in the line, is of the same order of magnitude as the flare area, expressed in heliocentric square degrees. Rise-times and decay-times of impulsive enhancements average about 2 min and 5 min, respectively. The maximum enhancements of radiation from ions in the chromosphere-corona transition region precede the H-alpha maximum by an average of 2 min, and occur in the same period of time as the hard component of solar X rays and the impulsive microwave bursts. Coronal lines in the extreme ultraviolet are less impulsive than the transition region lines in flare-related enhancements and their maxima follow the H-alpha maximum.