Using Web 2.0 to improve software quality

Social media tools are starting to become mainstream and those working in the software development industry are often ahead of the game in terms of using current technological innovations to improve their work. With the advent of outsourcing and distributed teams the software industry is ideally placed to take advantage of social media technologies, tools and environments. This paper looks at how social media is being used by early adopters within the software development industry. Current tools and trends in social media tool use are described and critiqued: what works and what doesn't. We use industrial case studies from platform development, commercial application development and government contexts which provide a clear picture of the emergent state of the art. These real world experiences are then used to show how working collaboratively in geographically dispersed teams, enabled by social media, can enhance and improve the development experience.

Differences in physical activity between black and white girls living in rural and urban areas

This study examined the relationship of race and rural/urban setting to physical, behavioral, psychosocial, and environmental factors associated with physical activity. Subjects included 1,668 eighth-grade girls from 31 middle schools: 933 from urban settings, and 735 from rural settings. Forty-six percent of urban girls and 59% of rural girls were Black. One-way and two-way ANOVAs with school as a covariate were used to analyze the data. Results indicated that most differences were associated with race rather than setting. Black girls were less active than White girls, reporting significantly fewer 30-minute blocks of both vigorous and moderate-to-vigorous physical activity. Black girls also spent more time watching television, and had higher BMIs and greater prevalence of overweight than White girls. However, enjoyment of physical education and family involvement in physical activity were greater among Black girls titan White girls. Rural White girls and urban Black girls had more favorable attitudes toward physical activity. Access to sports equipment, perceived safety of neighborhood, and physical activity self-efficacy were higher in White girls than Black girls.

Vibrational spectroscopy of the sulphate mineral sturmanite from Kuruman manganese deposits, South Africa

The mineral sturmanite is a hydrated calcium iron aluminium manganese sulphate tetrahydroxoborate hydroxide of formula Ca6(Fe, Al, Mn)2(SO4)2(B(OH)4)(OH)12•26H2O. We have studied the mineral sturmanite using a number of techniques, including SEM with EPMA and vibrational spectroscopy. Chemical analysis shows a homogeneous phase, composed by Ca, Fe, Mn, S, Al and Si. B is not determined in this EPMA technique. An intense Raman band at 990 cm−1 is assigned to the SO42− symmetric stretching mode. Raman spectroscopy identifies multiple sulphate symmetric stretching modes in line with the three sulphate crystallographically different sites. Raman spectroscopy also identifies a band at 1069 cm−1 which may be attributed to a carbonate symmetric stretching mode, indicating the presence of thaumasite. Infrared spectra display two bands at 1080 and 1107 cm−1 assigned to the SO42− antisymmetric stretching modes. The observation of multiple bands in this ν4 spectral region offers evidence for the reduction in symmetry of the sulphate anion from Td to C2v or even lower symmetry. The Raman band at 3622 cm−1 is assigned to the OH unit stretching vibration and the broad feature at around 3479 cm−1 to water stretching bands. Infrared spectroscopy shows a set of broad overlapping bands in the OH stretching region. Vibrational spectroscopy enables an assessment of the molecular structure of sturmanite to be made.

On secure multi-party computation in black-box groups

We study the natural problem of secure n-party computation (in the passive, computationally unbounded attack model) of the n-product function f G (x 1,...,x n ) = x 1 ·x 2 ⋯ x n in an arbitrary finite group (G,·), where the input of party P i is x i  ∈ G for i = 1,...,n. For flexibility, we are interested in protocols for f G which require only black-box access to the group G (i.e. the only computations performed by players in the protocol are a group operation, a group inverse, or sampling a uniformly random group element). Our results are as follows. First, on the negative side, we show that if (G,·) is non-abelian and n ≥ 4, then no ⌈n/2⌉-private protocol for computing f G exists. Second, on the positive side, we initiate an approach for construction of black-box protocols for f G based on k-of-k threshold secret sharing schemes, which are efficiently implementable over any black-box group G. We reduce the problem of constructing such protocols to a combinatorial colouring problem in planar graphs. We then give two constructions for such graph colourings. Our first colouring construction gives a protocol with optimal collusion resistance t < n/2, but has exponential communication complexity O(n*2t+1^2/t) group elements (this construction easily extends to general adversary structures). Our second probabilistic colouring construction gives a protocol with (close to optimal) collusion resistance t < n/μ for a graph-related constant μ ≤ 2.948, and has efficient communication complexity O(n*t^2) group elements. Furthermore, we believe that our results can be improved by further study of the associated combinatorial problems.

Herpes simplex 2 risk among women in a polygynous setting in rural West Africa

OBJECTIVES: To determine risk factors for herpes simplex 2 (HSV2) infection in women in a polygynous rural Gambian population. METHODS: Data from women who participated in a cross-sectional survey of reproductive health were matched to their own and, for women who had been or were married (ever-married), their spouses' data collected in a cross-sectional survey of fertility interests, including information on marital histories. RESULTS: Data were available on 150 never-married and 525 ever-married women. HSV2 prevalence was 16% amongst never-married women and 36% amongst ever-married women. For ever-married women, their own personal characteristics (age, ethnicity and genital cutting status) and events from their husbands' marriage history were important determinants of HSV2 infection. Women whose husbands married for the first time over age 35 were at greater risk than women whose husbands married by age 24 [odds ratio (OR) 2.72, 95% confidence interval (CI) 1.20-6.10]. Women whose husband reported interest in a new marriage were more likely to be HSV2 positive (OR 1.91, 95% CI 1.18-3.09). Women whose husbands were currently monogamous but had had previous marriages (OR 2.76, 95% CI 1.30-5.88) and women in currently polygynous marriages (OR 2.88, 95% CI 1.66-5.01) were three times as likely to be HSV2 positive as women who were their husband's only wife ever. CONCLUSION: Much transmission of HSV2 in this setting occurs within marriage where opportunity for personal protection is limited. High levels of transmission within marriage may undermine the impact of sexual behaviour change programmes aiming to reduce HSV2 and HIV incidence and complicate their evaluation.

Foreign direct investment and technology spillovers in sub-Saharan Africa

Foreign direct investment (FDI) is an effective conduit for technology transfer through technology spillovers to domestically owned firms in the host country. This study analyses the significance of productivity externalities of FDI to local firms, in terms of both intra-industry and inter-industry spillovers, using firm-level data from Kenya, Tanzania and Zimbabwe. The results show evidences in support of intra- and inter-industry productivity spillovers from FDI for Kenya and Zimbabwe. © 2010 Taylor & Francis.

Application of XRF and correspondence analysis to provenance studies of coastal and inland archaeological pottery from the Mngeni river area, South Africa

XRF spectrometry was applied to provenance studies of Iron Age pottery specimens that originated from the Mngeni river area in South Africa. Ten transition metals (Sc to Zn) mere determined in 107 potsherds, excavated from four different sites. The data were subjected to a computerized mathematical technique (correspondence analysis), which was used to group the samples according to the similarity of their elemental distributions. The groupings were interpreted in terms of social or cultural interaction between the sites. (C) 1997 by John Wiley & Sons, Ltd.

The use of correspondence analysis to compare major and trace elements for provenance studies of iron-age pottery from the Mngeni river area, South Africa

Provenance studies of iron-age pottery specimens originating from the Mngeni river area in South Africa was carried out by applying XRF spectrometry. A total of sixteen major and trace elements were analysed in a batch of 107 potsherds, excavated from four different archaeological sites in the aforementioned area. A multivariate statistical programme Correspondence Analysis was used in this study to obtain the relevant clustering patterns according to the similarity of the elemental distributions. Differences and similarities in the clusters obtained for the majors and trace elements are discussed.

One and the same: Integrative taxonomic evidence that Bactrocera invadens (Diptera: Tephritidae) is the same species as the Oriental fruit fly Bactrocera dorsalis

The invasive fruit fly Bactrocera invadens Drew, Tsuruta & White, and the Oriental fruit fly Bactrocera dorsalis (Hendel) are highly destructive horticultural pests of global significance. Bactrocera invadens originates from the Indian subcontinent and has recently invaded all of sub-Saharan Africa, while B. dorsalis principally occurs from the Indian subcontinent towards southern China and South-east Asia. High morphological and genetic similarity has cast doubt over whether B. invadens is a distinct species from B. dorsalis. Addressing this issue within an integrative taxonomic framework, we sampled from across the geographic distribution of both taxa and: (i) analysed morphological variation, including those characters considered diagnostic (scutum colour, length of aedeagus, width of postsutural lateral vittae, wing size, and wing shape); (ii) sequenced four loci (ITS1, ITS2, cox1 and nad4) for phylogenetic inference, and; (iii) generated a cox1 haplotype network to examine population structure. Molecular analyses included the closely related species, Bactrocera kandiensis Drew & Hancock. Scutum colour varies from red-brown to fully black for individuals from Africa and the Indian subcontinent. All individuals east of the Indian subcontinent are black except for a few red-brown individuals from China. The postsutural lateral vittae width of B. invadens is narrower than B. dorsalis from eastern Asia, but the variation is clinal, with subcontinent B. dorsalis populations intermediate in size. Aedeagus length, wing shape and wing size cannot discriminate between the two taxa. Phylogenetic analyses failed to resolve B. invadens from B. dorsalis, but did resolve B. kandiensis. Bactrocera dorsalis and B. invadens shared cox1 haplotypes, yet the haplotype network pattern does not reflect current taxonomy or patterns in thoracic colour. Some individuals of B. dorsalis/B. invadens possessed haplotypes more closely related to B. kandiensis than to conspecifics, suggestive of mitochondrial introgression between these species. The combined evidence fails to support the delimitation of B. dorsalis and B. invadens as separate biological species. Consequently, existing biological data for B. dorsalis may be applied to the invasive population in Africa. Our recommendation, in line with other recent publications, is that B. invadens be synonymized with B. dorsalis.

Wing morphology, echolocation calls, diet and emergence time of black-bearded tomb bats (Taphozous melanopogon, Emballonuridae) from southwest China

We studied the wing morphology, echolocation calls, diet and emergence time of the black-bearded tomb bat (Taphozous melanopogon) from May to October 2006 in Guangxi Province, southwest China. Taphozous melanopogon has wings with high aspect ratio, high loading and pointed wing-tip shape-characteristics associated with fast flight in open space. This species usually produces low-intensity, low frequency, and frequency-modulated (FM) calls usually containing up to four harmonics, with most energy in the second (or sometimes third) harmonic. The diet of this species consists mostly of Lepidoptera and Hemiptera. Timing of evening emergence is correlated with the time of sunset. This is the first study to describe the flight and echolocation behavior of this species in China, and opens the way for future studies of its biology.

Initial burden of disease estimates for South Africa, 2000

BACKGROUND This paper describes the first national burden of disease study for South Africa. The main focus is the burden due to premature mortality, i.e. years of life lost (YLLs). In addition, estimates of the burden contributed by morbidity, i.e. the years lived with disability (YLDs), are obtained to calculate disability-adjusted life years (DALYs); and the impact of AIDS on premature mortality in the year 2010 is assessed. METHOD Owing to the rapid mortality transition and the lack of timely data, a modelling approach has been adopted. The total mortality for the year 2000 is estimated using a demographic and AIDS model. The non-AIDS cause-of-death profile is estimated using three sources of data: Statistics South Africa, the National Department of Home Affairs, and the National Injury Mortality Surveillance System. A ratio method is used to estimate the YLDs from the YLL estimates. RESULTS The top single cause of mortality burden was HIV/AIDS followed by homicide, tuberculosis, road traffic accidents and diarrhoea. HIV/AIDS accounted for 38% of total YLLs, which is proportionately higher for females (47%) than for males (33%). Pre-transitional diseases, usually associated with poverty and underdevelopment, accounted for 25%, non-communicable diseases 21% and injuries 16% of YLLs. The DALY estimates highlight the fact that mortality alone underestimates the burden of disease, especially with regard to unintentional injuries, respiratory disease, and nervous system, mental and sense organ disorders. The impact of HIV/AIDS is expected to more than double the burden of premature mortality by the year 2010. CONCLUSION This study has drawn together data from a range of sources to develop coherent estimates of premature mortality by cause. South Africa is experiencing a quadruple burden of disease comprising the pre-transitional diseases, the emerging chronic diseases, injuries, and HIV/AIDS. Unless interventions that reduce morbidity and delay morbidity become widely available, the burden due to HIV/AIDS can be expected to grow very rapidly in the next few years. An improved base of information is needed to assess the morbidity impact more accurately.

Provincial mortality in South Africa, 2000 - priority-setting for now and a benchmark for the future

Background. Cause-of-death statistics are an essential component of health information. Despite improvements, underregistration and misclassification of causes make it difficult to interpret the official death statistics. Objective. To estimate consistent cause-specific death rates for the year 2000 and to identify the leading causes of death and premature mortality in the provinces. Methods. Total number of deaths and population size were estimated using the Actuarial Society of South Africa ASSA2000 AIDS and demographic model. Cause-of-death profiles based on Statistics South Africa's 15% sample, adjusted for misclassification of deaths due to ill-defined causes and AIDS deaths due to indicator conditions, were applied to the total deaths by age and sex. Age-standardised rates and years of life lost were calculated using age weighting and discounting. Results. Life expectancy in KwaZulu-Natal and Mpumalanga is about 10 years lower than that in the Western Cape, the province with the lowest mortality rate. HIV/AIDS is the leading cause of premature mortality for all provinces. Mortality due to pre-transitional causes, such as diarrhoea, is more pronounced in the poorer and more rural provinces. In contrast, non-communicable disease mortality is similar across all provinces, although the cause profiles differ. Injury mortality rates are particularly high in provinces with large metropolitan areas and in Mpumalanga. Conclusion. The quadruple burden experienced in all provinces requires a broad range of interventions, including improved access to health care; ensuring that basic needs such as those related to water and sanitation are met; disease and injury prevention; and promotion of a healthy lifestyle. High death rates as a result of HIV/AIDS highlight the urgent need to accelerate the implementation of the treatment and prevention plan. In addition, there is an urgent need to improve the cause-of-death data system to provide reliable cause-of-death statistics at health district level.

A clarion call for action based on refined DALY estimates for South Africa

Initial estimates of the burden of disease in South Africa in 20001 have been revised on the basis of additional data to estimate the disability-adjusted life-years (DALYs) for single causes for the first time in South Africa. The findings highlight the fact that despite uncertainty in the estimates, they provide important information to guide public health responses to improve the health of the nation...

Estimating the burden of disease attributable to smoking in South Africa in 2000

Objectives To quantify the burden of disease attributable to smoking in South Africa for 2000. Design The absolute difference between observed lung cancer death rate and the level in non-smokers, adjusted for occupational and indoor exposure to lung carcinogens, was used to estimate the proportion of lung cancer deaths attributable to smoking and the smoking impact ratio (SIR). The SIR was substituted for smoking prevalence in the attributable fraction formula for chronic obstructive pulmonary disease (COPD) and cancers to allow for the long lag between exposure and outcome. Assuming a shorter lag between exposure and disease, the current prevalence of smoking was used to estimate the population-attributable fractions (PAF) for the other outcomes. Relative risks (RR) from the American Cancer Society cancer prevention study (CPS-II) were used to calculate PAF. Setting South Africa. Outcome measures Deaths and disability-adjusted life years (DALYs) due to lung and other cancers, COPD, cardiovascular conditions, respiratory tuberculosis, and other respiratory and medical conditions. Results Smoking caused between 41 632 and 46 656 deaths in South Africa, accounting for 8.0 - 9.0% of deaths and 3.7 - 4.3% of DALYs in 2000. Smoking ranked third (after unsafe sex/sexually transmitted disease and high blood pressure) in terms of mortality among 17 risk factors evaluated. Three times as many males as females died from smoking. Lung cancer had the largest attributable fraction due to smoking. However, cardiovascular diseases accounted for the largest proportion of deaths attributed to smoking. Conclusion Cigarette smoking accounts for a large burden of preventable disease in South Africa. While the government has taken bold legislative action to discourage tobacco use since 1994, it still remains a major public health priority.