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Abstract: Drought is one of the costliest weather related natural hazards in the world. Traditionally, drought has been monitored using drought indices such as the “percent of normal precipitation” to provide policy makers with information on drought extent and severity so that timely intervention measures can be taken. This study was conducted to identify drought indices that strongly correlated with spring wheat yield and quality. Detailed crop and weather data were collected from a series of wheat experiments across Saskatchewan and Manitoba, providing a diverse range of wheat growing environments. The data collected from 2003 to 2006 provided 15 site-years of data, which were used to derive drought indices in four categories: (i) water supply, (ii) water demand, (iii) water balance and (iv) water use. The drought indices were accumulated either over selected periods of the crop growing season including 1-month, 2-month, 3-month and 4-month (May–August) and/or specific wheat growth periods i.e., from planting to anthesis, anthesis to maturity and planting to maturity. Drought indices explained from 27% to 74% (P <0.05) of the variation in wheat grain yield and four different wheat bread-making quality parameters for two different wheat genotypes (AC Barrie and Superb). The drought index category most highly correlated to the greatest number of wheat characteristics was water demand, followed by water balance, water use and water supply. These results imply that water demand (evapotranspiration, ET) and water balance provide the most accurate assessment of drought impacts on spring wheat yield and quality on the Canadian prairies. Consequently, water demand and water balance indices would be more useful in assessing agricultural drought than the water supply indices frequently used for meteorological drought. The Hargreaves et al. method of estimating ET produced indices with correlation coefficients similar to those of the more complex modified Penman–Monteith method. Drought indices accumulated from planting to anthesis were slightly superior to those accumulated over the entire growing season, but highly superior to those accumulated from anthesis to maturity. Based on these results it would be possible to generate preliminary estimates of drought impacts on spring wheat yield and quality by mid-season with some confidence. This could be very useful in regards to providing policy makers and grain merchants with early warning information to plan and prepare for potential drought conditions. [Copyright &y& Elsevier]

Odours emanating from livestock operations are a major concern to the non-farming public. Several field experiments were conducted to evaluate the magnitudes of odour emissions from hog slurry applied to grass and to identify management and meteorological factors that influence the rate of odour emissions. Management strategies evaluated included: slurry application rate, soil water status, slurry dilution, and simulated rainfall (irrigation) shortly after application. Results showed that doubling (120,000 L ha-1) the application rate had no impact on odour emissions. Tripling (180,000 L ha-1) the application rate, however, increased emissions on average by 28%, relative to the conventional (60,000 L ha-1) application rate. On average, diluting slurry decreased odour emissions by 11%, while simulated rainfall immediately after slurry application increased odour emissions by 17%. Applying slurry to wet soils compared with dry soils produced variable results. Odour fluxes increased with higher wind speed, net radiation and evapotranspiration rates. Odour emissions can, therefore, be reduced by following proper application rates, but most importantly, by applying slurry during calm, cool days. However, such stable weather conditions may increase odour persistence due to lack of vertical mixing, reduced transfer rates and slow drying of the slurry. [ABSTRACT FROM AUTHOR]

Odours emanating from livestock operations are a major concern to the non-farming public. Several field experiments were conducted to evaluate the magnitudes of odour emissions from hog slurry applied to grass and to identify management and meteorological factors that influence the rate of odour emissions. Management strategies evaluated included: slurry application rate, soil water status, slurry dilution, and simulated rainfall (irrigation) shortly after application. Results showed that doubling (120,000 L ha-1) the application rate had no impact on odour emissions. Tripling (180,000 L ha-1) the application rate, however, increased emissions on average by 28%, relative to the conventional (60,000 L ha-1) application rate. On average, diluting slurry decreased odour emissions by 11%, while simulated rainfall immediately after slurry application increased odour emissions by 17%. Applying slurry to wet soils compared with dry soils produced variable results. Odour fluxes increased with higher wind speed, net radiation and evapotranspiration rates. Odour emissions can, therefore, be reduced by following proper application rates, but most importantly, by applying slurry during calm, cool days. However, such stable weather conditions may increase odour persistence due to lack of vertical mixing, reduced transfer rates and slow drying of the slurry. [ABSTRACT FROM AUTHOR]

The loss of nitrogen (N) from field-applied animal manure through ammonia (NH3) volatilisation and nitrous oxide (N2O) emission is of major environmental concern. Both lime and dicyandiamide (DCD) have been suggested as amendments that can mitigate N2O emissions, but simultaneously increase the risk of NH3 volatilisation. This study evaluated the impact of lime and DCD on NH3 and N2O emissions following application of liquid hog manure. Hydrated lime (Ca(OH)2) was added to an acidic soil to achieve three pH levels (4.7, 6.3 and 7.4). Soil samples (100 g) were then placed in 500 ml screw-top Mason-jars and de-ionised water was added to bring the samples to 50, 70 and 90% water-filled pore space (WFPS). Slurry was applied at a rate equivalent to 116,000 l ha−1, while DCD was applied at 30% of the NH4-N rate applied. Jars were sealed and incubated at 21°C for 21 d. Ammonia volatilisation was quantified using boric acid traps, while N2O gas concentration was analysed using gas chromatography. Dicyandiamide had no effect ( P>0.05) on either NH3 or N2O emissions. Both NH3 and N2O emissions increased ( P<0.05) as WFPS increased, with emissions ranging from 0.9 to 1.4 kg NH3-N ha−1 and 123 to 353 g N2O-N ha−1, respectively. Liming decreased ( P<0.01) N2O emissions from 547 to 46 g N2O-N ha−1, but increased (p<0.01) NH3 volatilisation from 0.36 to 1.92 kg NH3-N ha−1. Results suggest that liming to a pH ≥6.3 can reduce N2O emissions, however, this reduction will be accompanied by a substantial loss of NH3. [ABSTRACT FROM AUTHOR]

Objectives: This study explored issues of sexuality in people living with AIDS who were on highly active antiretroviral therapy (HAART). Design: This was a descriptive quantitative study. Data were collected with an administered questionnaire and entered in Excel®. Statistical analysis included frequency tables, summary statistics and 95% confidence intervals. Setting and subjects: The respondents were purposively sampled from the 850 patients attending the antiretroviral clinic at Embhuleni Hospital in Mpumalanga province. Outcome measures: The questionnaire included questions on sexual practices, number of partners, sexual experience and fertility wishes, comparing respondents' experience before and after HAART. Results: There was a response rate of 100%, with 102 questionnaires completed. There was a significant difference between the responses to questions on sexual desire, sexual performance, sexual enjoyment and satisfaction regarding frequency of intercourse before and after HAART. Respondents reported a better sexual experience before HAART (t = 2.4387, p-value = 0.0165). There was a statistically significant difference between the number of partners before and after initiation of HAART (p-value = 0.000). Although 96% of respondents rated condom use as being very important, 11% never used condoms during sex and 21% indicated that they had had unprotected sex in the previous six months. Eighteen per cent of respondents said it was very important for them to have a child and 20% were planning to have a child in the future. A quarter of respondents had not disclosed their HIV status to their partners. The majority (95%) of respondents indicated that it was very important to them that health workers discussed their sexual needs with them. Conclusion: Sexuality in HIV is complex, with components described as the "Ps" of sexuality: practices, partners, pleasure, pressure and pain, procreation and power. In this study, participants reported a better sexual experience before HAART. Healthcare professionals need to develop the skills to discuss sexuality, intimacy and fertility wishes with patients. This discussion will enhance healthcare professionals' understanding of patients' experiences of their illness and should allow for a more effective patient-centred approach to care. [ABSTRACT FROM AUTHOR]

A need exists to improve the utilization of manure nutrients by minimizing NH3 emissions from land application of manure. Management strategies to reduce NH3 emissions are available; however, few have been validated under Canadian conditions. A well tested and accurate simulation model, however, can help overcome this challenge by determining appropriate management strategies for a given set of field conditions. The Volt'Air simulation model was utilized to estimate NH3 volatilization from manure spreading for various manure spreading considerations under a range of atmospheric conditions typically encountered in eastern Canada. Considerations included: (i) soil liming, (ii) time of day of manure spreading, (iii) rainfall (timing and amount) and (iv) manure incorporation (timing, depth and manure coverage). Results demonstrated that liming to increase soil pH, increased NH3 emissions by 3.3kg ha¿1 for each increment of 0.1 pH (up to a 1.5 total increase), over no liming at 34.6kg ha¿1. For each hour delay in manure spreading past 0800h, NH3 losses were reduced by 1.5kg ha¿1. Rainfall (10mm) at least 20h after manure application reduced losses, with increased reductions at higher rainfall amounts. Incorporation soon (1h) after application was best for NH3 mitigation. Increasing the depth of incorporation by 5cm reduced NH3 emissions by 4.4kg ha¿1; also increasing manure coverage by incorporation reduced losses by 2kg ha¿1 for each 10% increase in coverage, compared to surface application at 34.6kg ha¿1. This investigation using Volt'Air yielded valuable information about simulating manure management strategies and the magnitude of their effects on NH3 emissions. [Copyright &y& Elsevier]

The HIV/AIDS epidemic in Sub-Saharan Africa poses a massive diffusion and persuasion challenge for health professionals. Individuals working with adolescents to prevent the spread of HIV/AIDS must gain an understanding of adolescent's preference in obtaining information about HIV/AIDS and sexual behaviors. This study describes the primary and preferred sources of information regarding HIV/AIDS and sexual risk behavior in relation to several socio-demographic variables (n=941) in Swaziland, Southern Africa. Although print/broadcast media was the primary source for HIV/AIDS and sexual risk behavior information for the students, most participants preferred information from the healthcare workers. This study suggests a greater role for healthcare providers in providing HIV/AIDS and sexual risk information. [ABSTRACT FROM AUTHOR]