Physics of Flow Mechanism of Scour around Submerged Pipelines on an Erodible Bed

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Community-based prevention leads to an increase in condom use and a reduction in sexually transmitted infections (STIs) among men who have sex with men (MSM) and female sex workers (FSW): the Frontiers Prevention Project (FPP) evaluation results

<p>Abstract</p> <p>Background</p> <p>India has an estimated 2.0 million to 3.1 million people living with HIV; it has the highest number of HIV-positive people in Asia and ranks third in the world. The Frontiers Prevention Project (FPP) was implemented in 2002 to conduct targeted prevention intervention geared towards female sex workers (FSW) and men who have sex with men (MSM) in the state of Andhra Pradesh (AP). This paper reports the overall changes in behaviour and STI outcomes between 2003/4 and 2007 and also describes the changes attributed to the FPP.</p> <p>Methods</p> <p>The evaluation used two cross-sectional surveys among MSM and FSW at 24 sites in AP. Surveys were implemented using a similar methodology. Univariate analyses were conducted by comparing means: baseline vs. four-year follow-up and FPP vs. non-FPP. For both MSM and FSW, random and fixed-effects logit regression models at the site level were estimated for <it>condom use with last partner</it>, <it>syphilis sero-positivity </it>and <it>HSV 2 sero-positivity</it>. In addition, for FSW we estimated models for <it>condom use with regular partner</it>, and for MSM we estimated models for <it>condom use with last female partner</it>.</p> <p>Results</p> <p>Among MSM, fixed-effects analysis revealed that FPP was positively correlated with the probability of <it>condom use with last female sexual partner </it>and negatively correlated with the individual probability of <it>sero-positivity to syphilis and HSV 2</it>. Among FSW, the FPP intervention was significantly correlated with increased <it>condom use with regular partners </it>and with lower probability of <it>STI sero-positivity</it>.</p> <p>Discussion</p> <p>Important changes in behaviours related to an increase in prevention activities translated to reductions in STI sero-prevalence in AP, India. In contrast with non-FPP sites, the FPP sites experienced an intense community approach as part of the FPP intervention, and the general increase in condom use and its effect on STI sero-prevalence reflected the efficacy of these intense prevention activities focused on key populations in AP.</p

Measuring microbial biomass carbon by direct extraction - Comparison with chloroform fumigation-extraction

Soil microbial biomass, a small and highly dynamic organic matter pool, plays a critical role in soil fertility. Therefore it is important to have an accurate and rapid method to measure microbial biomass carbon (C). The chloroform fumigation extraction (CFE) method is used by most researchers, but it is quite time-consuming. The direct extraction method where the chloroform exposure and extraction steps are combined is quicker but not often used because it is not clear if it is as reliable as the CFE method. Using 20 Australian soils with a wide range in soil properties, we measured microbial biomass C with the CFE and the direct method. Chloroform labile C extracted by the two methods was correlated (r = 0.87), but it was significantly (p < 0.05) higher with the direct extraction method compared to CFE. Chloroform labile C extracted by both methods was significantly (p < 0.05) positively correlated with clay content, but the correlation coefficient was higher with the direct extraction method. The coefficient of variation for chloroform labile C was greater with the CFE than with the direct extraction method. Chloroform labile C extracted by the direct extraction method did not change between 0.5 and 4 h of shaking with K2SO4 solution and chloroform. We conclude that the chloroform labile C concentrations measured with the CFE method are comparable with those determined by the direct extraction method which is quicker and has a lower variability among replicates. © 2012 Elsevier Masson SAS.Raj Setia, Suman Lata Verma, Petra Marschne

Simulation of salinity effects on past, present, and future soil organic carbon stocks

Soil organic carbon (SOC) models are used to predict changes in SOC stocks and carbon dioxide (CO(2)) emissions from soils, and have been successfully validated for non-saline soils. However, SOC models have not been developed to simulate SOC turnover in saline soils. Due to the large extent of salt-affected areas in the world, it is important to correctly predict SOC dynamics in salt-affected soils. To close this knowledge gap, we modified the Rothamsted Carbon Model (RothC) to simulate SOC turnover in salt-affected soils, using data from non-salt-affected and salt-affected soils in two agricultural regions in India (120 soils) and in Australia (160 soils). Recently we developed a decomposition rate modifier based on an incubation study of a subset of these soils. In the present study, we introduce a new method to estimate the past losses of SOC due to salinity and show how salinity affects future SOC stocks on a regional scale. Because salinity decreases decomposition rates, simulations using the decomposition rate modifier for salinity suggest an accumulation of SOC. However, if the plant inputs are also adjusted to reflect reduced plant growth under saline conditions, the simulations show a significant loss of soil carbon in the past due to salinization, with a higher average loss of SOC in Australian soils (55 t C ha(-1)) than in Indian soils (31 t C ha(-1)). There was a significant negative correlation (p < 0.05) between SOC loss and osmotic potential. Simulations of future SOC stocks with the decomposition rate modifier and the plant input modifier indicate a greater decrease in SOC in saline than in non-saline soils under future climate. The simulations of past losses of SOC due to salinity were repeated using either measured charcoal-C or the inert organic matter predicted by the Falloon et al. equation to determine how much deviation from the Falloon et al. equation affects the amount of plant inputs generated by the model for the soils used in this study. Both sets of results suggest that saline soils have lost carbon and will continue to lose carbon under future climate. This demonstrates the importance of both reduced decomposition and reduced plant input in simulations of future changes in SOC stocks in saline soils.Raj Setia, Pete Smith, Petra Marschner, Pia Gottschalk, Jeff Baldock, Vipan Verma, Deepika Setia and Jo Smit

Sexual Behaviors and Partner-Specific Correlates of Heterosexual Anal Intercourse Among Truck Drivers and Their Wives in South India

It is important to know about patterns of sexual behaviors among married couples in order to develop effective HIV prevention strategies for them. Herein we describe the sexual behaviors, estimate prevalence of anal intercourse (AI) among truck drivers (‘‘truckers’’) and their wives, and determine partner-specific demographic and behavioral correlates of AI. We carried out a cluster-sampled cross-sectional survey among 18–49 year-old wives and their trucker husbands in a south Indian district. Data were collected by same-gender research team members with color-coded computer-assisted interviews. We used random intercept logistic regression to identify the independent correlates of AI. Thirteen percent of 475 wives and 467 truckers reported ever having AI with their spouse. Of those who responded, 55 % of 40 wives and 47 % of 36 truckers never used condoms during AI. Of those who responded, 22 of 32 wives and 24 of 32 husbands felt that condoms were unnecessary during AI. Reporting ever having AI was associated with younger age and higher education of both husband and wife. AI reported by wives was associated with having sexual partner(s) other than husband (adjusted OR 8.8 [95 % CI 3.2–24.0]), correctly answering all HIV knowledge items (adjusted OR 4.9 [95 % CI 1.9–12.5]), husband’s sexual debut occurring before marriage (adjusted OR 1.9 [95 % CI 1.0–3.5]), and husband’s high HIV risk perception (adjusted OR 2.5 [95 % CI 1.2–5.4]). AI reported by truckers was associated with having sex with a male or transgender (adjusted OR 4.0 [95 % CI 1.2–13.3]). Reported prevalence of AI was high considering that in India anal sex is non-normative, heavily stigmatized and, criminal. Indian heterosexual mobile populations need to be informed about the greater risk of HIV infection consequent to unprotected AI