Work organization research at the National Institute for Occupational Safety and Health.

For 25 years, the National Institute for Occupational Safety and Health (NIOSH) has conducted and sponsored laboratory, field, and epidemiological studies that have helped define the role of work organization factors in occupational safety and health. Research has focused on the health effects of specific job conditions, occupational stressors in specific occupations, occupational differences in the incidence of stressors and stress-related disorders, and intervention strategies. NIOSH and the American Psychological Association have formalized the concept of occupational health psychology and developed a postdoctoral training program. The National Occupational Research Agenda recognizes organization of work as one of 21 national occupational safety and health research priority areas. Future research should focus on industries, occupations, and populations at special risk; the impact of work organization on overall health; the identification of healthy organization characteristics; and the development of intervention strategies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A Clinical Trial to Test the Feasibility of a Telehealth Psychoeducational Intervention for Persons With Schizophrenia and Their Families: Intervention and 3-Month Findings.

Objective: To evaluate the feasibility of a telehealth psychoeducation intervention for persons with schizophrenia and their family members. Study Design: Randomized controlled trial. Participants: 30 persons with schizophrenia and 21 family members or other informal support persons. Interventions: Web-based psychoeducation program that provided online group therapy and education. Main Outcome Measures: Measures for persons with schizophrenia included perceived stress and perceived social support; for family members, they included disease-related distress and perceived social support. Results: At 3 months, participants with schizophrenia in the intervention group reported lower perceived stress (p = .04) and showed a trend for a higher perceived level of social support (p = .06). Conclusions: The findings demonstrate the feasibility and impact of providing telehealth-based psychosocial treatments, including online therapy groups, to persons with schizophrenia and their families. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A comparison of Landsat TM and MODIS vegetation indices for estimating forage phenology in desert bighorn sheep (Ovis canadensis nelsoni) habitat in the Sonoran Desert,USA

Sonoran Desert bighorn sheep (Ovis canadensis mexicana) occupy rugged upland areas that experience irregular periods of vegetation growth associated with precipitation events. These episodic and often spatially limited events provide important forage and preformed water resources that may be important drivers of animal movement and habitat use. Habitat-use models that incorporate forage phenology would broaden our understanding of desert bighorn ecology and have considerable potential to inform conservation efforts for the species. Field-based methods are of limited utility to characterize vegetation phenology across large areas. Vegetation indices (VI) derived from satellite imagery are a viable alternative, but may be confounded by areas of high relief and shadow effects that can degrade VI values. The varying spatial and temporal resolutions of readily available satellite sensors, such as the Landsat thematic mapper (TM) and moderate-resolution imaging spectrometer (MODIS), present additional challenges. In this study, we sought to minimize degrading effects of terrain on TM- and MODIS-based estimates of vegetation phenology. We compared effects of high topographic relief on time series MODIS- and TM-based VI such as the normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI) using VI departures from average (DA) in shaded and unshaded areas. Sun elevation angle negatively impacted TM-derived NDVI and EVI values in areas of steep terrain. In contrast, MODIS-derived NDVI values were insensitive to sun elevation and terrain effects, whereas MODIS-derived EVI was degraded in areas of steep terrain. Time series MODIS NDVI and EVI DA values differed significantly during months of low sun elevation angle. Average MODIS EVI departure values were ≥20% lower than NDVI under these conditions, confounding time series estimates of plant phenology. Our best results were obtained from MODIS 16-day composited NDVI. These remote-sensing-based VI estimates of seasonal plant phenology and productivity can be used to inform models of habitat use and movements of desert bighorn over large areas.     

Serum ferritin, hemoglobin, and Helicobacter pylori infection: a seroepidemiologic survey comprising 2794 Danish adults

Subtilisin-like serine protease, which is associated with the dormant spores of Bacillus cereus, was solubilized by washing the spores with 2 M KCl and purified to homogeneity by carbobenzoxy-D-phenylalanine-liganded affinity column chromatography and hydrophobic interaction column chromatography. Enzyme activity was completely inhibited by reagents for sulfhydryl groups such as HgCl2 as well as by conventional subtilisin inhibitors, suggesting the enzyme to be cysteine-dependent. The enzyme retained activity in 5 M urea at 4 degrees C for at least 2 months, and the specific activity was 50 times that of subtilisin BPN when measured for a common chromogenic substrate, carbobenzoxy-glycyl-glycyl-L-leucine p-nitroanilide. The gene encoding this protease was cloned in Escherichia coli, and its nucleotide sequence was analyzed. The deduced amino acid sequence suggested that the protease is produced as a precursor comprising three portions; a signal sequence (28 amino acid residues), a prosequence (80 amino acid residues) and a mature enzyme (289 amino acid residues). The mature region of the enzyme had high similarity with a thermitase from Thermoactinomyces vulgaris (72% identity) and a thermostable alkaline protease from Thermoactinomyces sp. E79 (66% identity), which have the N-terminal sequence showing scarcely noticeable similarity with corresponding stretches of subtilisins and mercuric ion-sensitive free cysteine in the equivalent position of the primary structure.     

The dynamics of collagen deposition in liver damaged by CCl4

The rates of synthesis and catabolism of collagen are determined in the livers of normal rats and of rats treated with carbon tetrachloride. Several experimental conditions are applied with the intention of investigating the dynamic processes separately, in order to determine the relevant values. The deposition of collagen in liver after damage by CCl4 is a consequence of the reduction of turnover with a simultaneous increase in collagen-production. Together with the increase in synthesis, which seems to be a consequence of a numerical increase in cells, there is a reduction in catabolism of collagen: the more severe the damage, the more marked is the decrease of specific catabolism. Collagen-deposition in the liver is thus the result of accumulation. The results indicate the possibility that collagen-catabolism is effected by enzymes produced by adjacent parenchymal cells, so that their destruction enhances the accumulation of collagen material. The findings mentioned above are discussed in the context of the general criteria of scar-formation and the repair of damaged tissues.     

Conductivity Measurement Using Four Linear Electrodes Embedded Inside a Rectangular Sample

Using solid materials prepared by melting or sintering allows inert metal electrodes to be embedded inside the solid. The I–V relations for four linear electrodes embedded inside a rectangular sample are evaluated. Two cases are considered: (a) a sample with uniform electronic (electron/hole) conductivity and (b) the electron/hole partial current in a sample that is a mixed ionic-electronic conductor with a nonuniform electron/hole distribution. Equations are derived which allow the determination of the conductivity from four-electrode measurements if a pure electronic conductor is considered or if a mixed ionic-electronic conductor is considered with the ionic current being blocked.     

Helicobacter pylori infection and socioeconomic factors among adult Danes

The aim of this study was to examine the relationship between housing conditions, educational level, occupational factors, and serologically diagnosed acute and chronic Helicobacter pylori infection. IgG, IgM, and IgA antibodies against Helicobacter pylori were measured by ELISA techniques in sera obtained from a random sample of 3589 Danes participating in a population study. Poor social status (odds ratio 2.2 [1.7-3.0]), short duration of schooling (odds ratio 2.0 [1.3-2.5]), lack of vocational training/education (odds ratio 1.4 [1.2-1.7]), unskilled work (odds ratio 1.7 [1.2-2.5]), and high work-related energy expenditure (odds ratio 1.4 [1.1-1.9]) increased the likelihood of chronic Helicobacter pylori infection. Chronic Helicobacter pylori infection was frequently found in people with a history of living abroad. Increased levels solely of IgM antibodies to H. pylori, interpreted as a sign of acute infection, were found more often in people who were divorced (odds ratio 2.3 [1.2-4.4]) or unmarried (odds ratio 2.0 [1.1-3.8]) and in people who worked long hours (odds ratio 2.0 [1.1-4.0]). In conclusion, educational and occupational factors relate to the likelihood of chronic Helicobacter pylori infection in adults. The rate of acute Helicobacter pylori infection is probably increased in single adults.     

How climate-smart is conservation agriculture (CA)? – its potential to deliver on adaptation,mitigation and productivity on smallholder farms in southern Africa

Climate resilient cropping systems are required to adapt to the increasing threats of climate change projected for Southern Africa and to better manage current climate variability. Conservation agriculture (CA) has been proposed among technologies that are climate-smart. For a cropping system to be labelled “climate-smart” it has to deliver three benefits: a) adapt to the effects of climate and be of increased resilience; b) mitigate climate effects by sequestering carbon (C) and reducing greenhouse gas emissions (GHG); and c) sustainably increase productivity and income. Research on smallholder farms from Southern Africa was analysed to assess if CA can deliver on the three principles of climate-smart agriculture. Results from Southern Africa showed that CA systems have a positive effect on adaptation and productivity, but its mitigation potential lags far behind expectations. CA systems maintain higher infiltration rates and conserve soil moisture, which helps to overcome seasonal dry-spells. Increased productivity and profitability were recorded although a lag period of 2–5 cropping seasons is common until yield benefits become significant. Immediate economic benefits such as reduced labour requirements in some systems will make CA more attractive in the short term to farmers who cannot afford to wait for several seasons until yield benefits accrue. The available data summarizing the effects of CA on soil organic C (SOC) and reductions in greenhouse gases, are often contradictory and depend a great deal on the agro-ecological environment and the available biomass for surface residue retention. There is an urgent need for more research to better quantify the mitigation effects, as the current data are scanty. Possible co-interventions such as improved intercropping/relay cropping systems, agroforestry and other tree-based systems may improve delivery of mitigation benefits and need further exploration.     

Normal-incidence reflectance of crystalline K(6)C(60), Rb(6)C(60), and Cs(6)C(60)

The structure factors and normal-incidence reflectances of the alkali-metal-doped fulleride crystals M(6)C(60) (where M = K, Rb, or Cs) were calculated, and the peak reflectances are in the 2-20% range for incident wavelengths of 9-17 ?, which indicates that C(60) may be a promising transmissive (spacer) material for normal-incidence mirrors that have relatively high normal-incidence reflectance in the x-ray region.     

Glimepiride, a new once-daily sulfonylurea. A double-blind placebo-controlled study of NIDDM patients. Glimepiride Study Group

OBJECTIVE: To compare the efficacy and safety of two daily doses of the new sulfonylurea, glimepiride (Amaryl), each as a once-daily dose or in two divided doses, in patients with NIDDM. RESEARCH DESIGN AND METHODS: Of the previously treated NIDDM patients, 416 entered this multicenter randomized double-blind placebo-controlled fixed-dose study. After a 3-week placebo washout, patients received a 14-week course of placebo or glimepiride 8 mg q.d., 4 mg b.i.d., 16 mg q.d., or 8 mg b.i.d. RESULTS: Fasting plasma glucose (FPG) and HbA1c values were similar at baseline in all treatment groups. The placebo group's FPG value increased from 13.0 mmol/l at baseline to 14.5 mmol/l at the last evaluation endpoint (P < or = 0.001). In contrast, FPG values in the four glimepiride groups decreased from a range of 12.4-12.9 mmol/l at baseline to a range of 8.6-9.8 mmol/l at endpoint (P < or = 0.001, within-group change from baseline; P < or = 0.001, between-group change [vs. placebo] from baseline). Two-hour postprandial plasma glucose (PPG) findings were consistent with FPG findings. In the placebo group, the HbA1c value increased from 7.7% at baseline to 9.7% at endpoint (P < or = 0.001), whereas HbA1c values for the glimepiride groups were 7.9-8.1% at baseline and 7.4-7.6% at endpoint (P < or = 0.001, within-group change from baseline; P < or = 0.001, between-group change from baseline). There were no meaningful differences in glycemic variables between daily doses of 8 and 16 mg or between once- and twice-daily dosing. Adverse events and laboratory data demonstrate that glimepiride has a favorable safety profile. CONCLUSIONS: Glimepiride is an effective and well-tolerated oral glucose-lowering agent. The results of this study demonstrate maximum effectiveness can be achieved with 8 mg q.d. of glimepiride in NIDDM subjects.