532 research outputs found
Quantitative estimates of fish abundance from boat electrofishing
Multiple removals by boat electro-fishing were used to estimate fish populations in non-wadeable habitats in New Zealand lakes and rivers. Mean capture probability was 0.47Ā±h0.10 (Ā± 95% CI) from 35 population estimates made with 2-7 successive removals. The relationship between the population estimate from the Zippin method (Y)and the number of fish caught in the first removal (X) was significant (adjusted r2=0.84, P<0.001; Figure 2). The least-squares regression was Y = 1.55X 1.23. Mean density Ā± 95% confidence interval for 13 fishing occasions was 30Ā±27 fish 100 m-
2. Mean biomass of fish for sites was 78Ā±39 g m-2 (range 29 to 245 g m-2). Koi carp comprised the largest proportion of the fish biomass wherever they were present. The high biomasses of koi carp estimated in these results (mean 56Ā±33 g m-2) suggest that they can reach problematic abundances in New Zealand. Bioniass of spawning koi carp can exceed 400 g m-2
An Algorithm for Distributing Coalitional Value Calculations among Cooperating Agents
The process of forming coalitions of software agents generally requires calculating a value for every possible coalition which indicates how beneficial that coalition would be if it was formed. Now, instead of having a single agent calculate all these values (as is typically the case), it is more efficient to distribute this calculation among the agents, thus using all the computational resources available to the system and avoiding the existence of a single point of failure. Given this, we present a novel algorithm for distributing this calculation among agents in cooperative environments. Specifically, by using our algorithm, each agent is assigned some part of the calculation such that the agentsā shares are exhaustive and disjoint. Moreover, the algorithm is decentralized, requires no communication between the agents, has minimal memory requirements, and can reflect variations in the computational speeds of the agents. To evaluate the effectiveness of our algorithm, we compare it with the only other algorithm available in the literature for distributing the coalitional value calculations (due to Shehory and Kraus). This shows that for the case of 25 agents, the distribution process of our algorithm took less than 0.02% of the time, the values were calculated using 0.000006% of the memory, the calculation redundancy was reduced from 383229848 to 0, and the total number of bytes sent between the agents dropped from 1146989648 to 0 (note that for larger numbers of agents, these improvements become exponentially better)
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Little Capitalists: The Social Economy of Saving in the United States, 1816-1914
In the early nineteenth-century United States, many social reformers, public commentators, and legislators argued that workers must engage in prudent financial planning in order to remain independent in a capitalist economy. Their belief that personal mismanagement was the primary cause of poverty led some of them to create the first financial institutions to help Americans of limited means save and invest their earnings: savings banks. From this modest start rose both a widespread ideology that related personal financial practice to personal virtue and a multibillion dollar industry that used the savings of millions of American workers to finance government, business, and personal debt. "Little Capitalists" charts this evolution from the philanthropic savings banks of the early-nineteenth century to the myriad commercial, cooperative, and public financial institutions for the working classes of the early-twentieth century. It shows how conceptions of individual and civic responsibility interacted with actual savings practices to integrate American workers into the national economy, building the financial apparatus that funded the expansion of wage-labor capitalism by harnessing the capital of wage laborers themselves.
American institutional savings pioneers sought to address increased poverty wrought by urban growth and the creation of a wage-earning class in the first half of the nineteenth century. These reformers organized the country's original savings banks on the premise that all workers were capable of saving some of their earnings--no matter how little--so that they could remain financially independent in times of unemployment, injury, or old age. Their institutions tried to teach workers how to save money by providing secure facilities in which they could do so in the small amounts that no other financial institutions would handle. They also offered depositors a chance to earn a small profit from interest paid on deposits. Because this interest derived from investing those deposits in securities, mortgages, and other loans, savings banks brought millions of nineteenth-century wage earners into the American economy as investors. In this way, these institutions promoted the idea that working-class depositors could be their own "capitalists."
As more Americans saved growing amounts, legislators, political economists, social reformers, and other observers took it as evidence that any worker who exercised virtues like thrift and self-denial could save money. Because generations of Americans viewed these personal attributes as the bases of moral civilization, they increasingly looked to savings institutions to foster a better citizenry and nation. The US Congress chartered the Freedman's Savings and Trust Company after the Civil War not only to provide financial services to former slaves but also to train them for a life of citizenship grounded in the principles of free labor ideology. Likewise, a nationwide movement beginning in the late-nineteenth century brought together governments, educators, and bankers to create a system of school savings banks to inculcate virtue in children by teaching them how to save pennies and nickels. In both cases, the point was to mold a working class steeped in the social, political, and moral values that would make them amenable to the emerging system of wage-labor capitalism.
Even as some savings institutions attempted social indoctrination, workers' growing deposits also demonstrated their financial power. From the 1870s to the 1910s, this motivated entrepreneurs and legislators to design and encourage new institutions to collect savings deposits and invest them widely, including: industrial life insurance firms, employee thrift plans, trust company and commercial bank savings departments, and a postal savings system. Meanwhile, organizations like building and loan associations slowly added the extension of working-class credit to the collection of working-class savings. These new institutions gave many Americans increased discretion over how to save (and spend) money. But as they began to utilize them, workers also became a significant component of the nation's for-profit finance economy as both creditors and debtors. In the process, they assumed new financial risk.
"Little Capitalists" outlines this history. It shows how a group of social experiments designed to foster an independent working class in the early-nineteenth century spawned, by the second decade of the twentieth century, both an ideology of saving at the center of popular perceptions about good citizenship and a small finance industry that was indispensable to the American economy
Association between Serum 25-Hydroxy Vitamin D Levels and the Prevalence of Adult-Onset Asthma
The major circulating metabolite of vitamin D (25(OH)D) has been implicated in the pathogenesis for atopic dermatitis, asthma and other allergic diseases due to downstream immunomodulatory effects. However, a consistent association between 25(OH)D and asthma during adulthood has yet to be found in observational studies. We aimed to test the association between 25(OH)D and asthma during adulthood and hypothesised that this association would be stronger in non-atopic participants. Using information collected on the participants of the 1958 birth cohort, we developed a novel measure of atopic status using total and specific IgE values and reported history of eczema and allergic rhinitis. We designed a nested case-control analysis, stratified by atopic status, and using logistic regression models investigated the association between 25(OH)D measured at age 46 years with the prevalence of asthma and wheezy bronchitis at age 50 years, excluding participants who reported ever having asthma or wheezy bronchitis before the age of 42. In the fully adjusted models, a 10 nmol/L increase in serum 25(OH)D prevalence had a significant association with asthma (aOR 0.94; 95% CI 0.88–1.00). There was some evidence of an atopic dependent trend in the association between 25(OH)D levels and asthma. Further analytical work on the operationalisation of atopy status would prove useful to uncover whether there is a role for 25(OH)D and other risk factors for asthma
An exploratory study on how workplace bullying is conceptualised in the Australasian media
Workplace bullying continues to be a prominent issue in both New Zealand and Australian workplaces. Victims of workplace bullying suffer a multitude of grievances on a personal and working level, reducing their job satisfaction and job performance, whilst increasing levels of absenteeism and likelihood of quitting the organisation. An organisation which enables workplace bullying to remain unresolved is breaching legal statutes in Australasia, which require that employers provide a safe environment for their workers. This paper reports on an analysis of some 200 media articles from Australasia regarding the issue of workplace bullying, with a view to understanding how bullying is represented in the media. From a work-environment hypothesis view, the analysis sought to determine whether bullying was portrayed as predominantly a product of the work environment, or as a largely interpersonal concern. The findings of this paper suggest that although reports of the words ācultureā and āenvironmentā are present, particularly in New Zealand articles, there is little evidence from media accounts to indicate that Australasian sources perceive the issue of workplace bullying as one that is derivative from an organisationās workplace environment. The implications of this finding indicate that Australasian media sources are placing the blame of bullying behaviours on the actions of employees, rather than holding organisations responsible for creating an environment that enables workplace bullying behaviours to occur
Fuel poverty increases risk of mould contamination, regardless of adult risk perception & ventilation in social housing properties
INTRODUCTION: Fuel poverty affects 2.4 million UK homes leading to poor hygrothermal conditions and risk of mould and house dust mite contaminations, which in turn increases risk of asthma exacerbation. For the first time we assess how fuel poverty, occupants' risk perception and use of mechanical ventilation mediate the risk of mould contamination in social housing. METHODS: Postal questionnaires were sent to 3867 social housing properties to collect adult risk perception, and demographic and environmental information on occupants. Participant details were linked to data pertaining to the individual properties. Multiple logistic regression was used to calculate odds ratios and confidence intervals while allowing for clustering of individuals coming from the same housing estate. We used Structured Equation Modelling and Goodness of Fit analysis in mediation analyses to examine the role of fuel poverty, risk perception, use of ventilation and energy efficiency. RESULTS: Eighteen percent of our target social housing populations (671 households) were included into our study. High risk perception (score of 8-10) was associated with reduced risk of mould contamination in the bedrooms of children (OR 0.5 95% CI; 0.3-0.9) and adults (OR 0.4 95% CI; 0.3-0.7). High risk perception of living with inadequate heating and ventilation reduced the risk of mould contamination (OR 0.5 95% CI; 0.3-0.8 and OR 0.5 95% CI; 0.3-0.7, respectively). Participants living with inadequate heating and not heating due to the cost of fuel had an increased risk of mould contamination (OR 3.4 95% CI; 2.0-5.8 and OR 2.2 95% CI; 1.5-3.2, respectively). Increased risk perception and use of extractor fans did not mediate the association between fuel poverty behaviours and increased risk of mould contamination. DISCUSSION: Fuel poverty behaviours increased the risk of mould contamination, which corresponds with existing literature. For the first time we used mediation analysis to assess how this association maybe modified by occupant behaviours. Increased risk perception and use of extractor fans did not modify the association between fuel poverty and mould contamination. This suggests that fuel poor populations may not benefit from energy efficiency interventions due to ineffective heating and ventilation practices of those occupants residing participating households. Our findings may be modified by a complex interaction between occupant behaviours and the built environment. We found that participant age, occupancy, SES, pets, drying washing indoors, geographic location, architectural design/age of the property, levels of insulation and type of heating regulated risk of mould contamination. CONCLUSION: Fuel poverty behaviours affected around a third of participating households and represent a risk factor for increased exposures to damp and mouldy conditions, regardless of adult risk perception, heating and ventilation practices. This requires multidisciplinary approach to assess the complex interaction between occupant behaviours, risk perception, the built environment and the effective use of heating and ventilation practices. STUDY IMPLICATIONS: Our findings have implications for housing policies and future housing interventions. Effective communication strategies focusing on awareness and perception of risk may help address indoor air quality issues. This must be supported by improved household energy efficiency with the provision of more effective heating and ventilation strategies, specifically to help alleviate those suffering from fuel poverty.European Regional Development Fund ProgrammeĀ 202497 50002
Association of pesticides and kidney function among adults in the US population 2001ā2010
Chronic kidney disease of unknown cause is prevalent in a range of communities; however, its etiology remains unclear. We examined the association between pesticide exposures and the risk of kidney function loss using four waves of the National Health and Nutrition Examination Survey (NHANES) to identify a pathological pathway. We pooled data from four cross-sectional waves of NHANES, with 41,847 participants in total. Exposure to malathion increased the risk of low kidney function (aOR = 1.26, 95% CI = 1.01ā1.56) in the adjusted model. Increased risk of low kidney function was not found among those exposed to 2,4-D (aOR = 0.88, 95% CI = 0.72ā1.09), 3,5,6-trichloropyridinol (aOR = 0.96, 95% CI = 0.83ā1.12), and 3-PBA (aOR = 1.03, 95% CI = 0.94ā1.13). Our findings provide evidence of altered kidney function in people exposed to malathion, highlighting the potential of organophosphate pesticidesā role in renal injury
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Exploring Item Order in Anxiety-Related Constructs: Practical Impacts of Serial Position
The present study was designed to test for item order effects by measuring four distinct constructs that contribute substantively to anxiety-related psychopathology (i.e., anxiety sensitivity, fear of negative evaluation, injury/illness sensitivity, and intolerance of uncertainty). Participants (n = 999; 71% women) were randomly assigned to complete measures for each construct presented in one of two modalities: (a) items presented cohesively as measures or (b) items presented randomly interspersed with one another. The results suggested that item order had a relatively small impact on item endorsement, response patterns, and reliabilities. The small impact was such that item order appears unlikely to influence clinical decisions related to these measures. These findings not only have implications for these and other similar measures, but further inform a long-standing debate about whether item grouping is a substantial concern in measurement. Accessed 6,950 times on https://pareonline.net from April 21, 2012 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right
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