Single measurement to predict potential mineralizable nitrogen

Non-Peer ReviewedAlthough soil nitrate nitrogen (N) has been used as a basis for N fertilizer recommendation in western Canada, potential mineralizable N should be (or is) a more accurate indicator of the N supplying power of the soil. Potential mineralizable N, analyzed by extraction with hot KCl, and organic matter content were determined on the AESA Soil Quality Benchmark Sites in Alberta. Using these results, we developed an approach to estimate Nt from soil organic matter, based on the equation Nt=No(1-e-kt)y, and validated the calculated Nt with the hot KCl extracted N. Results indicated that the potential mineralizable N released from soil differed among ecoregions and slope positions. Potential mineralizable N is lower in southern Alberta than central Alberta. The lower slopes released more N than higher slope positions. Nt released in soil over the growing season correlated well with hot KCl extracted N in three different slope positions. However, variability of Nt in the upper slope position was greater than middle and lower slopes due to a shallow A horizon and variable soil moisture during the growing season. After removal of outliers (9% of the total data set), the values of R2 (regression of hot KCl with calculated Nt) are 0.529, 0.576 and 0.627 for upper, middle and lower slope position, respectively. Using calculated Nt results, a potential mineralizable map in Alberta has been developed. This map will guide producers to manage soil as well as fertilizer N

BioRock:new experiments and hardware to investigate microbe–mineral interactions in space

In this paper, we describe the development of an International Space Station experiment, BioRock. The purpose of this experiment is to investigate biofilm formation and microbe–mineral interactions in space. The latter research has application in areas as diverse as regolith amelioration and extraterrestrial mining. We describe the design of a prototype biomining reactor for use in space experimentation and investigations on in situ Resource Use and we describe the results of pre-flight tests

Gender and respiratory findings in workers occupationally exposed to organic aerosols: A meta analysis of 12 cross-sectional studies

<p>Abstract</p> <p>Background</p> <p>Gender related differences in respiratory disease have been documented. The aim of this study was to investigate gender related differences in respiratory findings by occupation. We analyzed data from 12 of our previously published studies.</p> <p>Methods</p> <p>Three thousand and eleven (3011) workers employed in "organic dust" industries (1379 female and 1632 male) were studied. A control group of 806 workers not exposed to any kind of dust were also investigated (male = 419, female = 387). Acute and chronic respiratory symptoms and lung function were measured. The weighted average method and the Mantel-Haentszel method were used to calculate the odds ratios of symptoms. Hedge's unbiased estimations were used to measure lung function differences between men and women.</p> <p>Results</p> <p>There were high prevalences of acute and chronic respiratory symptoms in all the "dusty" studied groups compared to controls. Significantly less chronic cough, chronic phlegm as well as chronic bronchitis were found among women than among men after the adjustments for smoking, age and duration of employment. Upper respiratory tract symptoms by contrast were more frequent in women than in men in these groups. Significant gender related lung function differences occurred in the textile industry but not in the food processing industry or among farmers.</p> <p>Conclusion</p> <p>The results of this study suggest that in industries processing organic compounds there are gender differences in respiratory symptoms and lung function in exposed workers. Whether these findings represent true physiologic gender differences, gender specific workplace exposures or other undefined gender variables not defined in this study cannot be determined. These data do not suggest that special limitations for women are warranted for respiratory health reasons in these industries, but the issue of upper respiratory irritation and disease warrants further study.</p

Occupation, smoking, and chronic obstructive respiratory disorders: a cross sectional study in an industrial area of Catalonia, Spain

BACKGROUND: Few studies have investigated the independent effects of occupational exposures and smoking on chronic bronchitis and airflow obstruction. We assessed the association between lifetime occupational exposures and airflow obstruction in a cross-sectional survey in an urban-industrial area of Catalonia, Spain. METHODS: We interviewed 576 subjects of both sexes aged 20–70 years (response rate 80%) randomly selected from census rolls, using the ATS questionnaire. Forced spirometry was performed by 497 subjects according to ATS normative. RESULTS: Lifetime occupational exposure to dust, gases or fumes was reported by 52% of the subjects (63% in men, 41% in women). Textile industry was the most frequently reported job in relation to these exposures (39%). Chronic cough, expectoration and wheeze were more prevalent in exposed subjects with odds ratios ranging from 1.7 to 2.0 being highest among never-smokers (2.1 to 4.3). Lung function differences between exposed and unexposed subjects were dependent on duration of exposure, but not on smoking habits. Subjects exposed more than 15 years to dusts, gases or fumes had lower lung function values (FEV(1 )-80 ml, 95% confidence interval (CI) -186 to 26; MMEF -163 ml, CI -397 to 71; FEV(1)/FVC ratio -1.7%, CI -3.3 to -0.2) than non-exposed. CONCLUSION: Chronic bronchitis symptoms and airflow obstruction are associated with occupational exposures in a population with a high employment in the textile industry. Lung function impairment was related to the duration of occupational exposure, being independent of the effect of smoking

International equity portfolio investment and enforcement of insider trading laws: a cross-country analysis

In this study, we examine the effects of stringent insider trading laws’ enforcement, institutions and stock market development on international equity portfolio allocation using data from 44 countries over the period 2001-2015. Our results suggest that stringent insider trading laws and their enforcement exert a positive and significant impact on international portfolio investment allocation. Further analysis indicates that the interaction between a country’s institutional quality, stock market development and enforcement of insider trading laws have a positive and significant effect on international equity portfolio allocation. The findings of this study have implications for the design of portfolio investment trading strategies and contribute to the literature on foreign equity investment decisions