An Analysis Of Shift Work: Compensating Differentials And Local Economic Conditions

The theory of compensating differentials asserts that workers facing undesirable work conditions, such as night shift work, should receive compensating wage differentials. The theory assumes that workers can easily find jobs with desirable characteristics; thus, compensating wages are necessary to induce workers to take jobs with undesirable characteristics. This dissertation considers a variation of the theory of compensating differentials in which labor markets are weak. If workers are more likely to work night shifts in areas with weak economic conditions and if firms are less likely to offer compensating differentials for night shift work in areas with weak economic conditions, weak regional economies may lead to smaller compensating differentials for night shift work. Using nlsy79 data from 1990-2000, this paper employs an endogenous switching regression model to analyze wages of day and night shift workers and shift choice. The model is estimated using both the lee two-step method and maximum likelihood. Two measures of local economic conditions, the local unemployment rate and the state leading index, are used. The models provide evidence that shift differentials and local economic conditions significantly impact shift choice. Of the two local economic condition variables used in the analysis, the leading index is a stronger predictor of shift choice. This paper develops a new method of analyzing the impact of the interaction between the shift differential and local economic conditions on shift choice, providing limited evidence that compensating differentials for night shift work may be lower when local economies are weak. The calculated interaction effects are small. Estimated wage premiums for night shift work are negative, and are approximately half of day wages in the 1990 cross-section. Estimated wage differentials for night shift work are smaller in pooled cross-section analysis, ranging from roughly 2% to 11% below day wages. Analyzing cross-sections over time indicates that shift differentials were below day wages throughout most of the 1990\u27s but in 2000, night wages were approximately 7-11% higher than day wages. Overall, the results provide evidence that individuals take both the size of the wage premium and local labor market conditions into account when selecting working hours

SB27-09/10: Athletic Fee Increase

SB27-09/10: Athletic Fee Increase. This resolution passed 15Y-5N-1A on a roll call vote during the April 14, 2010 meeting of the Associated Students of the University of Montana (ASUM)

MaizeGDB's new data types, resources and activities

MaizeGDB is the Maize Genetics and Genomics Database. Available at MaizeGDB are diverse data that support maize research including maps, gene product information, loci and their various alleles, phenotypes (both naturally occurring and as a result of directed mutagenesis), stocks, sequences, molecular markers, references and contact information for maize researchers worldwide. Also available through MaizeGDB are various community support service bulletin boards including the Editorial Board's list of high-impact papers, information about the Annual Maize Genetics Conference and the Jobs board where employment opportunities are posted. Reported here are data updates, improvements to interfaces and changes to standard operating procedures that have been made during the past 2 years. MaizeGDB is freely available and can be accessed online at

Offshore Membrane Enclosures for Growing Algae (OMEGA: A System for Biofuel Production, Wastewater Treatment, and CO2 Sequestration

We are developing Offshore Membrane Enclosures for Growing Algae (OMEGA). OMEGAs are closed photo-bioreactors constructed of flexible, inexpensive, and durable plastic with small sections of semi-permeable membranes for gas exchange and forward osmosis (FO). Each OMEGA modules is filled with municipal wastewater and provided with CO2 from coastal CO2 sources. The OMEGA modules float just below the surface, and the surrounding seawater provides structural support, temperature control, and mixing for the freshwater algae cultures inside. The salinit7 gradient from inside to outside drives forward osmosis through the patches of FO membranes. This concentrates nutrients in the wastewater, which enhances algal growth, and slowly dewaters the algae, which facilitates harvesting. Thy concentrated algal biomass is harvested for producing biofuels and fertilizer. OMEGA system cleans the wastewater released into the surrounding coastal waters and functions as a carbon sequestration system

Surface Laplacian of Central Scalp Electrical Signals is Insensitive to Muscle Contamination

Author version made available in accordance with the publisher's policy. "(c) 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works."Abstract—Objective: To investigate the effects of surface Laplacian processing on gross and persistent electromyographic (EMG) contamination of electroencephalographic (EEG) signals in electrical scalp recordings. Methods: We made scalp recordings during passive and active tasks, on awake subjects in the absence and in the presence of complete neuromuscular blockade. Three scalp surface Laplacian estimators were compared to left ear and common average reference (CAR). Contamination was quantified by comparing power after paralysis (brain signal, B) with power before paralysis (brain plus muscle signal, B+M). Brain:Muscle (B:M) ratios for the methods were calculated using B and differences in power after paralysis to represent muscle (M). Results: There were very small power differences after paralysis up to 600 Hz using surface Laplacian transforms (B:M> 6 above 30 Hz in central scalp leads). Conclusions: Scalp surface Laplacian transforms reduce muscle power in central and peri-central leads to less than one sixth of the brain signal, 2-3 times better signal detection than CAR. Significance: Scalp surface Laplacian transformations provide robust estimates for detecting high frequency (gamma) activity, for assessing electrophysiological correlates of disease, and also for providing a measure of brain electrical activity for use as a ‘standard’ in the development of brain/muscle signal separation methods

Constitutive spectral EEG peaks in the gamma range: suppressed by sleep, reduced by mental activity and resistant to sensory stimulation

This Document is Protected by copyright and was first published by Frontiers. All rights reserved. it is reproduced with permission. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.Objective: In a systematic study of gamma activity in neuro-psychiatric disease, we unexpectedly observed distinctive, apparently persistent, electroencephalogram (EEG) spectral peaks in the gamma range (25–100 Hz). Our objective, therefore, was to examine the incidence, distribution and some of the characteristics of these peaks. Methods: High sample-rate, 128-channel, EEG was recorded in 603 volunteers (510 with neuropsychiatric disorders, 93 controls), whilst performing cognitive tasks, and converted to power spectra. Peaks of spectral power, including in the gamma range, were determined algorithmically for all electrodes. To determine if peaks were stable, 24-h ambulatory recordings were obtained from 16 subjects with peaks. In 10 subjects, steady-state responses to stimuli at peak frequency were compared with off-peak-frequency stimulation to determine if peaks were a feature of underlying network resonances and peaks were evaluated with easy and hard versions of oddball tasks to determine if peaks might be influenced by mental effort. Results: 57% of 603 subjects exhibited peaks >2 dB above trough power at or above 25 Hz. Larger peaks (>5 dB) were present in 13% of subjects. Peaks were distributed widely over the scalp, more frequent centrally. Peaks were present through the day and were suppressed by slow-wave-sleep. Steady-state responses were the same with on- or off-peak sensory stimulation. In contrast, mental effort resulted in reductions in power and frequency of gamma peaks, although the suppression did not correlate with level of effort. Conclusions: Gamma EEG can be expressed constitutively as concentrations of power in narrow or wide frequency bands that play an, as yet, unknown role in cognitive activity. Significance: These findings expand the described range of rhythmic EEG phenomena. In particular, in addition to evoked, induced and sustained gamma band activity, gamma activity can be present constitutively in spectral peaks

GeneLink: a database to facilitate genetic studies of complex traits

BACKGROUND: In contrast to gene-mapping studies of simple Mendelian disorders, genetic analyses of complex traits are far more challenging, and high quality data management systems are often critical to the success of these projects. To minimize the difficulties inherent in complex trait studies, we have developed GeneLink, a Web-accessible, password-protected Sybase database. RESULTS: GeneLink is a powerful tool for complex trait mapping, enabling genotypic data to be easily merged with pedigree and extensive phenotypic data. Specifically designed to facilitate large-scale (multi-center) genetic linkage or association studies, GeneLink securely and efficiently handles large amounts of data and provides additional features to facilitate data analysis by existing software packages and quality control. These include the ability to download chromosome-specific data files containing marker data in map order in various formats appropriate for downstream analyses (e.g., GAS and LINKAGE). Furthermore, an unlimited number of phenotypes (either qualitative or quantitative) can be stored and analyzed. Finally, GeneLink generates several quality assurance reports, including genotyping success rates of specified DNA samples or success and heterozygosity rates for specified markers. CONCLUSIONS: GeneLink has already proven an invaluable tool for complex trait mapping studies and is discussed primarily in the context of our large, multi-center study of hereditary prostate cancer (HPC). GeneLink is freely available at

Veggie ISS Validation Test Results and Produce Consumption

The Veggie vegetable production system flew to the International Space Station (ISS) in the spring of 2014. The first set of plants, Outredgeous red romaine lettuce, was grown, harvested, frozen, and returned to Earth in October. Ground control and flight plant tissue was sub-sectioned for microbial analysis, anthocyanin antioxidant phenolic analysis, and elemental analysis. Microbial analysis was also performed on samples swabbed on orbit from plants, Veggie bellows, and plant pillow surfaces, on water samples, and on samples of roots, media, and wick material from two returned plant pillows. Microbial levels of plants were comparable to ground controls, with some differences in community composition. The range in aerobic bacterial plate counts between individual plants was much greater in the ground controls than in flight plants. No pathogens were found. Anthocyanin concentrations were the same between ground and flight plants, while antioxidant and phenolic levels were slightly higher in flight plants. Elements varied, but key target elements for astronaut nutrition were similar between ground and flight plants. Aerobic plate counts of the flight plant pillow components were significantly higher than ground controls. Surface swab samples showed low microbial counts, with most below detection limits. Flight plant microbial levels were less than bacterial guidelines set for non-thermostabalized food and near or below those for fungi. These guidelines are not for fresh produce but are the closest approximate standards. Forward work includes the development of standards for space-grown produce. A produce consumption strategy for Veggie on ISS includes pre-flight assessments of all crops to down select candidates, wiping flight-grown plants with sanitizing food wipes, and regular Veggie hardware cleaning and microbial monitoring. Produce then could be consumed by astronauts, however some plant material would be reserved and returned for analysis. Implementation of this plan is a step toward developing pick-and-eat food production to supplement the packaged diet on ISS and for future exploration missions where plants could make up a larger portion of the diet. Supported by NASA Space Biology Program

The Effects of Patient Function and Dependence on Costs of Care in Alzheimer's Disease

OBJECTIVES: To estimate incremental effects of patients' dependence and function on costs of care during the early stages of Alzheimer's disease (AD) and to compare strengths of their relationships with different cost components. DESIGN: Multicenter, cross-sectional, observational study. SETTING: Three university hospitals in the United States. PARTICIPANTS: One hundred seventy-nine community-living patients with probable AD, with modified Mini-Mental State Examination scores of 30 or higher. MEASUREMENTS: Patients' dependence was measured using the Dependence Scale (DS). Functional capacity was measured using the Blessed Dementia Rating Scale (BDRS). Total cost was measured by summing direct medical costs and informal costs. Direct medical costs included costs of hospitalization, outpatient treatment and procedures, assistive devices, and medications. Informal costs were estimated from time spent helping with basic and instrumental activities of daily living for up to three caregivers per patient using national average hourly earnings as wage rate. RESULTS: DS and BDRS were associated with higher total cost; a 1-point increase in DS was associated with a $1,832 increase in total cost, and a 1-point increase in BDRS was associated with a$3,333 increase. Examining component costs separately identified potential differences between DS and BDRS. A 1-point increase in BDRS was associated with a $1,406 increase in direct medical cost. A 1-point increase in DS was associated with a$1,690 increase in informal cost. CONCLUSION: Patients' dependence and function related differently to direct medical and informal cost, suggesting that measures of function and dependence provided unique information for explaining variations in cost of care for patients with AD, highlighting the value in measuring both constructs

Self-Reported Periodization of Nutrition in Elite Female and Male Runners and Race Walkers

Athletes should achieve event-specific physiological requirements through careful periodization of training, underpinned by individualized and targeted nutrition strategies. However, evidence of whether, and how, elite endurance athletes periodize nutrition is scarce. Accordingly, elite international female (n = 67) and male (n = 37) middle/long-distance athletes (IAAF score: 1129 ± 54, corresponds to 13:22.49 [males] and 15:17.93 [females] in the 5000 m) completed an online survey (February–May 2018) examining self-reported practices of dietary periodization for micro (within/between-days), meso (weeks/months) and macro (across the year) contexts. Data are shown as the percentage of all athletes practicing a given strategy followed by the % of athletes reporting various beliefs or practices within this strategy. Differences according to sex, event (middle-distance [800 m/1500 m] vs. track-distance [3000 m-10000 m] vs. road-distance [marathon/race walks]), caliber (high [major championship qualifier] vs. lower), and training volume (low/moderate/high male and female tertiles) were analyzed using Chi-square test or Kruskal–Wallis Test and indicated statistically different when p ≤ 0.05. Most athletes reported eating more on hard training days (92%) and focusing on nutrition before (84%; carbohydrate intake [63%] and timing [58%]) and after (95%; protein goals [59%], timing [55%], carbohydrate goals [50%]) key sessions. Road-distance were the most (62 and 57%), and middle-distance the least (30 and 30%) likely to train fasted (p = 0.037) or restrict carbohydrates periodically (p = 0.050), respectively. Carbohydrate intake during training (58% of total) was more common in males (79%; p = 0.004) and road-distance (90%; p < 0.001) than females (53%) or middle/track-distance (48 and 37%). Most athletes (83%) reported following a specific diet before and during race day, with half of the athletes focusing on carbohydrates. Nearly all (97%) road-distance athletes reported following a during-race nutrition plan (carbohydrates/fluids:89%). Only 32% reported taking advice from a dietitian/nutritionist. Based on our analysis: (1) Road-distance athletes periodize carbohydrate availability while track/middle-distance avoid low carbohydrate availability; (2) Middle-distance runners emphasize physique goals to guide their nutrition strategies; (3) Females seem to be more cautious of increasing energy/carbohydrate intake; (4) Among all athletes, nutrition strategies are chosen primarily to improve performance, followed by reasons related to physique, adaptation and health outcomes. Overall, these athletes appear to possess good knowledge of nutrition for supporting training and competition performance