Volatile hydrocarbons inhibit methanogenic crude oil degradation

Methanogenic degradation of crude oil in subsurface sediments occurs slowly, but without the need for exogenous electron acceptors, is sustained for long periods and has enormous economic and environmental consequences. Here we show that volatile hydrocarbons are inhibitory to methanogenic oil biodegradation by comparing degradation of an artificially weathered crude oil with volatile hydrocarbons removed, with the same oil that was not weathered. Volatile hydrocarbons (nC5-nC10, methylcyclohexane, benzene, toluene, and xylenes) were quantified in the headspace of microcosms. Aliphatic (n-alkanes nC12-nC34) and aromatic hydrocarbons (4-methylbiphenyl, 3-methylbiphenyl, 2-methylnaphthalene, 1-methylnaphthalene) were quantified in the total hydrocarbon fraction extracted from the microcosms. 16S rRNA genes from key microorganisms known to play an important role in methanogenic alkane degradation (Smithella and Methanomicrobiales) were quantified by quantitative PCR. Methane production from degradation of weathered oil in microcosms was rapid (1.1 ± 0.1 μmol CH4/g sediment/day) with stoichiometric yields consistent with degradation of heavier n-alkanes (nC12-nC34). For non-weathered oil, degradation rates in microcosms were significantly lower (0.4 ± 0.3 μmol CH4/g sediment/day). This indicated that volatile hydrocarbons present in the non-weathered oil inhibit, but do not completely halt, methanogenic alkane biodegradation. These findings are significant with respect to rates of biodegradation of crude oils with abundant volatile hydrocarbons in anoxic, sulphate-depleted subsurface environments, such as contaminated marine sediments which have been entrained below the sulfate-reduction zone, as well as crude oil biodegradation in petroleum reservoirs and contaminated aquifers

A range expanding signal conditioner

Telemetry system modifications to improve signal resolution are described. Process uses zero suppression technique which consists of subtracting known voltage from input and amplifying remainder. Schematic diagram of circuit is provided and details of operation are presented

A science of networks approach to ancient Maya sociopolitical organization

textWas ancient Maya sociopolitical organization, overall, centralized or decentralized? Does the application of a new technique of analysis, borrowed from the science of networks (network theory), aid in understanding Classic period sociopolitical organization? This dissertation seeks to explore Classic Maya sociopolitical organization through the application of small world and scale free models derived from the science of networks. The research presented combines archaeological fieldwork in northwestern Belize, Central America with evidence from ancient Maya inscriptions to evaluate the potential of applying network theory methods to studies of ancient Maya sociopolitical organization. This dissertation is divided into five chapters which provide an overview of the climate, physiography, flora, and fauna of the research area, an outline of previous archaeological research in the region, the general culture history of the area from the Paleoindian to the Postclassic periods, results of excavations and mapping at two sites very close to, or arguably part of the site of Dos Hombres, Belize. The final chapter is a review of select aspects of ancient Maya sociopolitical organization focusing on issues related to centralized and decentralized models, which have dominated research for the last 30 years. Through the analysis of network graphs I show that the science of networks can be used to gain insight into ancient Maya sociopolitical interaction. Taken as a whole, I find that Classic period sociopolitical interaction was decentralized and can be characterized as a scale free small world network. Further, network analysis provides insight into the roles of ancient Maya sites as hubs of the Classic period sociopolitical landscape. These findings, in general, tend to agree with previous attempts to rank sites based on volume of architecture and courtyard counts. Since the political system was dominated by few hubs with many links, it was vulnerable to dissolution if one or two of those hubs were destroyed. The presentation and analysis of network graphs yields insights into the nature of ancient Maya sociopolitical organization. Ceramic associations are briefly examined from a science of networks perspective. Results affirm that it is useful to apply network theory to the study of ancient Maya sociopolitical organization.Anthropolog

Mobilizing charity: non‐uniformed voluntary action during the First World War

This study proposes that the voluntary sector in the UK underwent major managerial and state‐directional change during the period of the Great War, as a concerted response to but also enabling it to make important contributions to the war effort. It provides an important challenge to that scholarship which presents charity and voluntary activity in this period as marking a downturn from the high point of late‐Victorian philanthropy, as representing far less serious activities than those undertaken by munitions workers, and VADs; with charitably‐minded civilians’ efforts alienating rather than encouraging to men at the front. The study seeks to demonstrate that such a depiction is incorrect; suggesting that the degree of negativity that surrounds much previous work on voluntary action in this period is reaching a myth‐like status. The study draws on previously unused primary sources in publicly available archives; notably regarding the developing role of the UK’s Director General of Voluntary Organizations (DGVO) from 1916, and regulatory legislation of the period; and on the activities of specified local charities, in particular areas, notably Croydon and Blackburn. It utilises a crossdisciplinary approach drawing on philanthropic, social, military and political history as well as the history of management. The career of the DGVO, Sir Edward Ward, is examined in detail and analysed from the perspectives of both contemporary and current management practice. The late 19th and early 20th centuries did not represent the zenith of charitable activity, this came during the war itself. Charitable donations rose to an all‐time peak and the scope and nature of charitable work shifted decisively. Far more working class activists, especially women became involved, though there were significant differences between the suburban south and industrial north of England and Scotland. Far from there being an unbridgeable gap in understanding or empathy between soldiers and civilians the links were strong and charitable contributions were enormously important in maintaining troop morale. This bond significantly contributed to the development and maintenance of social capital in Britain, which, in turn, strongly supported the war effort. Issues of developing social capital within voluntary organisations, and a review of the nature of the deference exchanges occurring within charitable activity at this time follow. Finally, the extent to which responsiveness to wartime needs was able to trigger managerial change, if not a managerial revolution among active voluntary organisations is considered. A series of appendices illustrate key aspects of charities’ development and direction during this period

Rape myth in true and false rape allegations

Police records of 38 rape allegations, evenly split into maintained-as-true and withdrawn-as-false categories were compared with 19 generated-false statements from recruited participants. The Illinois Rape Myth Acceptance Scale (IRMAS) was used to assess the attitudes of the participants and a content analysis derived from IRMAS was used to compare the three categories of allegation. Rape myths were present in all three allegation types. The two categories of false allegation both contained more rape myths than the true allegations but no differences were found between the generated and withdrawn false allegations. High scorers in IRMAS also produced more violent false accounts. In addition to these findings, this study provides support for the further examination of rape myths in both false and true statements and use of generated allegations as proxies for real false statements

Investigating Rubber Mats on Concrete Slats in Deep Pit Confinement Buildings for Finishing Cattle-progress Report

Confinement housing of beef cattle is becoming more common due to increased environmental concerns and the desire to capture potential efficiencies in cattle performance and manure value. Deep pit facilities with slatted floors are being built, however one of the disadvantages may be the effect on feet and legs and performance consequences forcattle being on concrete slats for extended periods of time. Rubber mats constructed to be installed over the slats are being used to overcome these issues. No comparable data has been gathered in typical U.S feeding situations to measure potential benefit of these mats. This investigation is attempting to gather data to determine potential advantages of the mats

Impacts of goat browsing on salt cedar stands in West Texas

The objectives were to measure goat performance and preference of saltcedar (SC) in a pasture setting as well as SC response to browsing. Sixteen Boer-cross goats were conditioned to SC in individual pens for 16 days. SC and basal diet intake was recorded during conditioning, as well as goat weights throughout the study. Ten goats were then placed in 20’X40’ pens situated in dense SC stands, three plots per treatment. Treatment 1 consisted of plots grazed once; Treatment 2 consisted of plots grazed twice, after sufficient re-growth was observed on the SC plants. Additionally, 18 SC seedlings were defoliated by hand and measured for height and mass. SC intake increased over time in the conditioning and field trials. Goat weight did not change. SC cover decreased following treatment but did not differ between treatments. Mortality did not occur in any seedlings but height and aboveground mass were reduced by defoliation

Comparative Efficiency Assessment of Primary Care Models Using Data Envelopment Analysis

This paper compares the productive efficiencies of four models of primary care service delivery in Ontario, Canada, using the data envelopment analysis (DEA) method. Particular care is taken to include quality of service as part of our output measure. The influence of the delivery model on productive efficiency is disentangled from patient characteristics using regression analysis. Significant differences are found in the efficiency scores across models and within each model. In general, the fee-for-service arrangement ranks the highest and the community-health-centre model the lowest in efficiency scoring. The reliance of our input measures on costs and number of patients, clearly favours the fee-for-service model. Patient characteristics contribute little to explaining differences in the efficiency ranking across the models.Productive Efficiency; DEA; Primary Health Care