South Africa is frequently subjected to severe droughts and dry spells during the rainy season. As such, rainfall is one of the most significant factors limiting dryland crop production in South Africa. The mid-summer period is particularly important for agriculture since a lack of rain during this period negatively affects crop yields. Dry spell frequency analyses are used to investigate the impacts of sub-seasonal rainfall variability on crop yield, since seasonal rainfall totals alone do not explain the relationship between rainfall and crop yields. This study investigated the spatial and temporal occurrences of the mid-summer dry spells based on magnitude, length and time of occurrence in the major maize growing areas of the summer rainfall region of South Africa. Three thresholds of 5 mm, 10 mm, and 15 mm total rainfall for a pentad were used for the analysis of dry spells. Dry spell analysis showed that dry pentads occur during mid-summer with differing intensity, duration and frequency across the summer rainfall region. Annual frequency of dry pentads for the mid-summer period ranged between 0 and 4 pentads for the 5 mm threshold and 1 to 7 for the 10 mm and 15 mm thresholds. The non-parametric Mann-Kendall trend analysis of the dry pentads indicates that there is no significant trend in the frequency of dry spells at a 95% confidence level. The initial and conditional probabilities of getting a dry spell using the Markov chain model also showed that there is a 32% to 80% probability that a single pentad will be dry using the 15 mm threshold. There is a 5% to 48% probability of experiencing two consecutive dry pentads and 1% to 29% probability of getting three consecutive dry pentads. The duration and intensity of dry spells, as well as the Markov chain probabilities, showed a decrease in dry spells from west to east of the maize-growing areas of the summer rainfall region of South Africa.

Abstract The objective of this work was to evaluate the nutritional quality in 3 cultivars of alfalfa, belonging to different winter dormancy (GRI), subjected to two cutting frequencies during one year of cultivation, based on the abundant information existing in studies carried out in productivity, coverage and persistence, not so in the determination of quality of forage subjected to different frequencies of cuts and contrasting GRI. Three cultivars (GR6-Verzy), (GR9-Mecha) and (GR10-Ruano) were tested. The experimental design was a complete split plot with four repetitions. Two treatments defined by the cutting intervals were established: T1: 25 days and T2: 35 days. These were specified for spring, summer and fall seasons. For winter the interval was 45 and 55 days in T1 and T2, respectively. The evaluated variables were: percentage of dry matter (% DM), percentage of crude protein (% PB), percentage of neutral detergent fiber (% FDN) and percentage of acid detergent fiber (% FDA). Significant differences were found for all the nutritional variables studied, for both treatment with p <0.05 with InfoStat program. Interaction between cultivars and treatment was observed for % PB. The 35 days cutoff frequency of yielded the lowest percentages of PB and the highest percentages of FDN and FDA. Hence the forage resulting from this frequency is of a lower quality, leading to decreased digestibility and lower performance of pasture for livestock.

Resumen El objetivo de este trabajo fue evaluar la calidad nutricional en 3 cultivares de alfalfa, pertenecientes a diferentes grupos de reposo invernal (GRI), sometidos a dos frecuencias de corte, durante un año del cultivo, fundamentado en que es abundante la información existente en estudios realizados en productividad, cobertura y persistencia, no así en la determinación de calidad de forraje sometidos a diferentes frecuencias de cortes y de GRI contrastantes. Se utilizaron tres cultivares (GR6-Verzy), (GR9-Mecha) y (GR10-Ruano). El diseño experimental fue de parcelas divididas con cuatro repeticiones. Se establecieron 2 tratamientos definidos por los intervalos entre cortes: T1: 25 días y T2: 35 días. Estos fueron precisados para las estaciones de primavera, verano y otoño. En invierno el intervalo fue de 45 y 55 días en T1 y T2, respectivamente. Las variables evaluadas fueron: porcentaje de materia seca (% MS), porcentaje de proteína bruta (% PB), porcentaje de fibra detergente neutro (% FDN) y porcentaje de fibra detergente ácido (% FDA). Se encontraron diferencias significativas para todas las variables nutricionales estudiadas, para ambos tratamientos. Se observó interacción entre cultivares y tratamiento para % PB. Los cultivares estudiados con diferentes GRI, no expresaron diferencias significativas en los parámetros de calidad evaluados para ninguna de las frecuencias de corte realizadas. La frecuencia de corte de 35 días arrojó los menores % PB y mayores % FDN y % FDA, por lo cual el forraje resulta para esta frecuencia de menor calidad, llevando a la disminución de la digestibilidad y aprovechamiento de la pastura para el ganado.

The study focused on yield-reliability analysis and operating rules for optimum scheduling of run-of-river (ROR) abstractions for typical rural water supply schemes using Siloam Village, Limpopo Province, South Africa, as a case study. Efficient operation of water supply systems requires operating rules as decision support tools. System operation methods have hardly been developed or applied to water supply to rural communities that depend on ROR abstractions. Simulated runoff was used to derive unregulated river yield at different levels of assurance of supply (LAS) for Nzhelele River at Siloam Village using 1-day flow duration curves. Yield-reliability analysis results were used to derive operating rules. The results show that Nzhelele River can meet domestic and low-flow requirements at 50-80% (1:2-1:5) LAS. The low-flow and domestic water requirements can be partially met at 90% (1:10) LAS. The generic operating rules for ROR abstractions were consequently derived from the procedure used in developing operating rules for Nzhelele River. This enables generation of operating rules for ROR abstractions in any typical rural water supply system.

The Global Smokefree Partnership has recently prepared a map of smokefree campaigns and policies around the world. It focuses primarily on countries that are parties to the WHO Framework Convention on Tobacco Control, but other countries were included. The smokefree status of 172 countries was mapped. Of these countries, 31 (18.0%) have established comprehensive smokefree policies, either nationally or at state or city level - best practice; 25 (14.6%) are planning to implement smokefree policies in 2008 or 2009; and 51(29.6%) are making significant progress with smokefree policies. Only 65 countries (37.8%) have limited or no smokefree polices. A selection of countries representing best practices in smokefree policies or planning to implement smokefree policies in 2008 or 2009 is highlighted. They illustrate the significant global momentum for smokefree policies, the success of established policies, the importance of civil society and the sharing of experience between countries.

El Global Smokefree Partnership recién completó un mapa de las campañas para promover políticas de ambientes libres de humo (ALH) a nivel mundial. El mapa se centra en los países Partes al Convenio Marco para el Control del Tabaco de la OMS, aunque otros países también se incluyen, y documenta el estatus de 172 países en el tema de los ALH. De estos países, 31 (18.0%) tienen políticas comprehensivas de ALH, a nivel nacional, provincial, y/o estatal - mejores prácticas; 25 (14.6%) prevén la implementación de políticas de ALH en 2008 o 2009; y 51 (29.6%) han progresado significativamente con estas políticas. Sólo 65 países (37.8%) no tienen políticas de ALH, o sólo políticas limitadas en este ámbito. Este ensayo destaca una selección de países que representan las mejores prácticas en las políticas de ALH o que prevén la implementación de estas políticas en 2008 o 2009, con tal de ilustrar el movimiento global hacia los ambientes libres de humo; el éxito de las políticas ya establecidas; la importancia de la sociedad civil en este proceso; y el intercambio de experiencias entre países.

The Global Smokefree Partnership has recently prepared a map of smokefree campaigns and policies around the world. It focuses primarily on countries that are parties to the WHO Framework Convention on Tobacco Control, but other countries were included. The smokefree status of 172 countries was mapped. Of these countries, 31 (18.0%) have established comprehensive smokefree policies, either nationally or at state or city level - best practice; 25 (14.6%) are planning to implement smokefree policies in 2008 or 2009; and 51(29.6%) are making significant progress with smokefree policies. Only 65 countries (37.8%) have limited or no smokefree polices. A selection of countries representing best practices in smokefree policies or planning to implement smokefree policies in 2008 or 2009 is highlighted. They illustrate the significant global momentum for smokefree policies, the success of established policies, the importance of civil society and the sharing of experience between countries.

El Global Smokefree Partnership recién completó un mapa de las campañas para promover políticas de ambientes libres de humo (ALH) a nivel mundial. El mapa se centra en los países Partes al Convenio Marco para el Control del Tabaco de la OMS, aunque otros países también se incluyen, y documenta el estatus de 172 países en el tema de los ALH. De estos países, 31 (18.0%) tienen políticas comprehensivas de ALH, a nivel nacional, provincial, y/o estatal - mejores prácticas; 25 (14.6%) prevén la implementación de políticas de ALH en 2008 o 2009; y 51 (29.6%) han progresado significativamente con estas políticas. Sólo 65 países (37.8%) no tienen políticas de ALH, o sólo políticas limitadas en este ámbito. Este ensayo destaca una selección de países que representan las mejores prácticas en las políticas de ALH o que prevén la implementación de estas políticas en 2008 o 2009, con tal de ilustrar el movimiento global hacia los ambientes libres de humo; el éxito de las políticas ya establecidas; la importancia de la sociedad civil en este proceso; y el intercambio de experiencias entre países.

OBJECTIVES: The aim of the investigation was to test the differences in the perceived level of dental anxiety among children treated restoratively using the Atraumatic Restorative Treatment (ART) approach, the traditional restorative (TRA) approach and ART aided with a chemomechanical caries removal gel (ART plus). METHODS: The study subjects were 6-7-year-old children. TRA was compared to ART in a clinical setting after children had seen a dentist twice (Group A), ART was compared to 'ART plus' in a clinical setting after children had seen a dentist once (Group B) and ART was applied outside the clinic on school premises (Group C). The treatments were carried out in Class II cavitated dentine lesion in primary molars. Dental anxiety was measured using the Venham Picture Test (VPT). Three-way analysis of variances and interaction was applied to test for treatment approach, gender and operator effects on the mean VPT scores. RESULTS: There was no statistically significant difference (p=0.80) observed between the mean VPT scores for the traditional approach and those for the ART approach and between ART with and without a chemomechanical caries removal gel (p=0.07). Children in Group A had lower mean VPT scores than children in Group B (p=0.02) and Group C (p<0.00001) when treated using the ART approach by the same two operators. CONCLUSIONS: The level of dental anxiety was low. There was no difference in level of dental anxiety observed in children treated with ART in comparison to the traditional restorative approach, and between children treated with ART with and without a chemomechanical caries removal gel. The treatment environment and prepatory visits may be factors determining the level of dental anxiety in children treated through the ART approach only.