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Reports on the defense of the paper 'A Critical Analysis of the Pharmacology of AZT and its Use in AIDS,' published in the periodical 'Current Medical Research and Opinion.' Its use by President Thabo Mbeki in the debate over the efficacy of AZT in South Africa; Comments by managing editor of the periodical Peter Clarke.

The article reports on the study conducted by Curtis Marean, an archeologist at the Arizona State University, regarding modern man's earliest seafood diet in Tempe, Arizona. Result shows that modern individuals integrated shellfish into their diets and it is proven on the evidences gathered by Marean and his team. Marean conducted his research on the caves of early modern humans in South Africa and they found mollusc in sediments on the cave floor that was dated around 164,000 years ago. Such findings made him conclude that shellfish consumption already exist thousands of years ago.

The article discusses the competition and cooperation in meerkat's reproduction. Description of a study conducted by Timothy Clutton-Brock for observing the behavioral and breeding patterns of the meerkat is presented. The article mentions the Kuruman River Reserve which is said to home for 15 different types of meerkat. The article details the data collection efforts of the research team from South Africa and mentions the findings of their study.

The article focuses on the impact high-quality cooperative research is having in helping countries improve nascent science infrastructure. It comments on collaborative science in Africa and mentions universities in South Africa generate nearly two-thirds of the fractional count (FC). It reports on how annual regional economic growth has helped bolster science in South and Central America. It presents charts of science networks in Central and Southern America, and in Africa.

There is consensus that the modern human lineage appeared in Africa before 100,000 years ago. But there is debate as to when cultural and cognitive characteristics typical of modern humans first appeared, and the role that these had in the expansion of modern humans out of Africa. Scientists rely on symbolically specific proxies, such as artistic expression, to document the origins of complex cognition. Advanced technologies with elaborate chains of production are also proxies, as these often demand high-fidelity transmission and thus language. Some argue that advanced technologies in Africa appear and disappear and thus do not indicate complex cognition exclusive to early modern humans in Africa. The origins of composite tools and advanced projectile weapons figure prominently in modern human evolution research, and the latter have been argued to have been in the exclusive possession of modern humans. Here we describe a previously unrecognized advanced stone tool technology from Pinnacle Point Site 5-6 on the south coast of South Africa, originating approximately 71,000 years ago. This technology is dominated by the production of small bladelets (microliths) primarily from heat-treated stone. There is agreement that microlithic technology was used to create composite tool components as part of advanced projectile weapons. Microliths were common worldwide by the mid-Holocene epoch, but have a patchy pattern of first appearance that is rarely earlier than 40,000 years ago, and were thought to appear briefly between 65,000 and 60,000 years ago in South Africa and then disappear. Our research extends this record to ?71,000?years, shows that microlithic technology originated early in South Africa, evolved over a vast time span (?11,000?years), and was typically coupled to complex heat treatment that persisted for nearly 100,000?years. Advanced technologies in Africa were early and enduring; a small sample of excavated sites in Africa is the best explanation for any perceived 'flickering' pattern. [ABSTRACT FROM AUTHOR]

The article provides information about "Nature" in South Africa. There are submissions to "Nature" coming from South African since January 2006. 15 authors who are working in South Africa have published original research in "Nature" in the past year. 75 percent of papers published in "Nature" that have contributing authors from South Africa have been in biological sciences.

Reports on the South African's publication of a paper on science and technology which acknowledges that a crisis is confronting the research sector. Launch of the paper that is deemed the basis of a new science and technology system; Decline in the spending on research; Other suggestions on research and development cited in the paper.

Antibodies capable of neutralizing HIV-1 often target variable regions 1 and 2 (V1V2) of the HIV-1 envelope, but the mechanism of their elicitation has been unclear. Here we define the developmental pathway by which such antibodies are generated and acquire the requisite molecular characteristics for neutralization. Twelve somatically related neutralizing antibodies (CAP256-VRC26.01-12) were isolated from donor CAP256 (from the Centre for the AIDS Programme of Research in South Africa (CAPRISA)); each antibody contained the protruding tyrosine-sulphated, anionic antigen-binding loop (complementarity-determining region (CDR) H3) characteristic of this category of antibodies. Their unmutated ancestor emerged between weeks 30-38 post-infection with a 35-residue CDR H3, and neutralized the virus that superinfected this individual 15 weeks after initial infection. Improved neutralization breadth and potency occurred by week 59 with modest affinity maturation, and was preceded by extensive diversification of the virus population. HIV-1 V1V2-directed neutralizing antibodies can thus develop relatively rapidly through initial selection of B cells with a long CDR H3, and limited subsequent somatic hypermutation. These data provide important insights relevant to HIV-1 vaccine development. [ABSTRACT FROM AUTHOR]

The article reports on the scientific discovery, based on calcite deposits' geomagnetic nature, which reveals that many of the artefacts and fossils found from the Sterkfontein Cave in South Africa were younger than initially established.

Specimens of Australopithecus sediba from the site of Malapa, South Africa (dating from approximately 2?million years (Myr) ago) present a mix of primitive and derived traits that align the taxon with other Australopithecus species and with early Homo. Although much of the available cranial and postcranial material of Au. sediba has been described, its feeding ecology has not been investigated. Here we present results from the first extraction of plant phytoliths from dental calculus of an early hominin. We also consider stable carbon isotope and dental microwear texture data for Au. sediba in light of new palaeoenvironmental evidence. The two individuals examined consumed an almost exclusive C3 diet that probably included harder foods, and both dicotyledons (for example, tree leaves, fruits, wood and bark) and monocotyledons (for example, grasses and sedges). Like Ardipithecus ramidus (approximately 4.4 Myr ago) and modern savanna chimpanzees, Au. sediba consumed C3 foods in preference to widely available C4 resources. The inferred consumption of C3 monocotyledons, and wood or bark, increases the known variety of early hominin foods. The overall dietary pattern of these two individuals contrasts with available data for other hominins in the region and elsewhere. [ABSTRACT FROM AUTHOR]

According to the 'Faint Young Sun' paradox, during the late Archaean eon a Sun approximately 20% dimmer warmed the early Earth such that it had liquid water and a clement climate. Explanations for this phenomenon have invoked a denser atmosphere that provided warmth by nitrogen pressure broadening or enhanced greenhouse gas concentrations. Such solutions are allowed by geochemical studies and numerical investigations that place approximate concentration limits on Archaean atmospheric gases, including methane, carbon dioxide and oxygen. But no field data constraining ground-level air density and barometric pressure have been reported, leaving the plausibility of these various hypotheses in doubt. Here we show that raindrop imprints in tuffs of the Ventersdorp Supergroup, South Africa, constrain surface air density 2.7 billion years ago to less than twice modern levels. We interpret the raindrop fossils using experiments in which water droplets of known size fall at terminal velocity into fresh and weathered volcanic ash, thus defining a relationship between imprint size and raindrop impact momentum. Fragmentation following raindrop flattening limits raindrop size to a maximum value independent of air density, whereas raindrop terminal velocity varies as the inverse of the square root of air density. If the Archaean raindrops reached the modern maximum measured size, air density must have been less than 2.3?kg?m?3, compared to today's 1.2?kg?m?3, but because such drops rarely occur, air density was more probably below 1.3?kg?m?3. The upper estimate for air density renders the pressure broadening explanation possible, but it is improbable under the likely lower estimates. Our results also disallow the extreme CO2 levels required for hot Archaean climates. [ABSTRACT FROM AUTHOR]

Since its discovery over two decades ago, the deep subsurface biosphere has been considered to be the realm of single-cell organisms, extending over three kilometres into the Earth's crust and comprising a significant fraction of the global biosphere. The constraints of temperature, energy, dioxygen and space seemed to preclude the possibility of more-complex, multicellular organisms from surviving at these depths. Here we report species of the phylum Nematoda that have been detected in or recovered from 0.9-3.6-kilometre-deep fracture water in the deep mines of South Africa but have not been detected in the mining water. These subsurface nematodes, including a new species, Halicephalobus mephisto, tolerate high temperature, reproduce asexually and preferentially feed upon subsurface bacteria. Carbon-14 data indicate that the fracture water in which the nematodes reside is 3,000-12,000-year-old palaeometeoric water. Our data suggest that nematodes should be found in other deep hypoxic settings where temperature permits, and that they may control the microbial population density by grazing on fracture surface biofilm patches. Our results expand the known metazoan biosphere and demonstrate that deep ecosystems are more complex than previously accepted. The discovery of multicellular life in the deep subsurface of the Earth also has important implications for the search for subsurface life on other planets in our Solar System. [ABSTRACT FROM AUTHOR]

Komatiites are ancient volcanic rocks, mostly over 2.7 billion years old (from the Archaean era), that formed through high degrees of partial melting of the mantle and therefore provide reliable information on bulk mantle compositions. In particular, the platinum group element (PGE) contents of komatiites provide a unique source of information on core formation, mantle differentiation and possibly core–mantle interaction. Most of the available PGE data on komatiites are from late Archaean (∼2.7–2.9 Gyr old) or early Proterozoic (2.0–2.5 Gyr old) samples. Here we show that most early Archaean (3.5–3.2 Gyr old) komatiites from the Barberton greenstone belt of South Africa and the Pilbara craton of Western Australia are depleted in PGE relative to late Archaean and younger komatiites. Early Archaean komatiites record a signal of PGE depletion in the lower mantle, resulting from core formation. This signal diminishes with time owing to progressive mixing-in to the deep mantle of PGE-enriched cosmic material that the Earth accreted as the ‘late veneer’ during the Early Archaean (4.5–3.8 Gyr ago) meteorite bombardment. [ABSTRACT FROM AUTHOR]

Predicting the evolution of climate over decadal timescales requires a quantitative understanding of the dynamics that govern the meridional overturning circulation (MOC). Comprehensive ocean measurement programmes aiming to monitor MOC variations have been established in the subtropical North Atlantic (RAPID, at latitude 26.5° N, and MOVE, at latitude 16° N) and show strong variability on intraseasonal to interannual timescales. Observational evidence of longer-term changes in MOC transport remains scarce, owing to infrequent sampling of transoceanic sections over past decades. Inferences based on long-term sea surface temperature records, however, supported by model simulations, suggest a variability with an amplitude of ±1.5–3 Sv (1 Sv = 106 m3 s-1) on decadal timescales in the subtropics. Such variability has been attributed to variations of deep water formation in the sub-arctic Atlantic, particularly the renewal rate of Labrador Sea Water. Here we present results from a model simulation that suggest an additional influence on decadal MOC variability having a Southern Hemisphere origin: dynamic signals originating in the Agulhas leakage region at the southern tip of Africa. These contribute a MOC signal in the tropical and subtropical North Atlantic that is of the same order of magnitude as the northern source. A complete rationalization of observed MOC changes therefore also requires consideration of signals arriving from the south. [ABSTRACT FROM AUTHOR]

One of the biggest challenges for conservation biology is to provide conservation planners with ways to prioritize effort. Much attention has been focused on biodiversity hotspots. However, the conservation of evolutionary process is now also acknowledged as a priority in the face of global change. Phylogenetic diversity (PD) is a biodiversity index that measures the length of evolutionary pathways that connect a given set of taxa. PD therefore identifies sets of taxa that maximize the accumulation of ‘feature diversity’. Recent studies, however, concluded that taxon richness is a good surrogate for PD. Here we show taxon richness to be decoupled from PD, using a biome-wide phylogenetic analysis of the flora of an undisputed biodiversity hotspot—the Cape of South Africa. We demonstrate that this decoupling has real-world importance for conservation planning. Finally, using a database of medicinal and economic plant use, we demonstrate that PD protection is the best strategy for preserving feature diversity in the Cape. We should be able to use PD to identify those key regions that maximize future options, both for the continuing evolution of life on Earth and for the benefit of society. [ABSTRACT FROM AUTHOR]

Although plate tectonics is the central geological process of the modern Earth, its form and existence during the Archaean era (4.0–2.5 Gyr ago) are disputed. The existence of subduction during this time is particularly controversial because characteristic subduction-related mineral assemblages, typically documenting apparent geothermal gradients of 15 °C km-1 or less, have not yet been recorded from in situ Archaean rocks (the lowest recorded apparent geothermal gradients are greater than 25 °C km-1). Despite this absence from the rock record, low Archaean geothermal gradients are suggested by eclogitic nodules in kimberlites and circumstantial evidence for subduction processes, including possible accretion-related structures, has been reported in Archaean terrains. The lack of spatially and temporally well-constrained high-pressure, low-temperature metamorphism continues, however, to cast doubt on the relevance of subduction-driven tectonics during the first 1.5 Gyr of the Earth's history. Here we report garnet–albite-bearing mineral assemblages that record pressures of 1.2–1.5 GPa at temperatures of 600–650 °C from supracrustal amphibolites from the mid-Archaean Barberton granitoid-greenstone terrain. These conditions point to apparent geothermal gradients of 12–15 °C—similar to those found in recent subduction zones—that coincided with the main phase of terrane accretion in the structurally overlying Barberton greenstone belt. These high-pressure, low-temperature conditions represent metamorphic evidence for cold and strong lithosphere, as well as subduction-driven tectonic processes, during the evolution of the early Earth. [ABSTRACT FROM AUTHOR]

Responds to South African President Thabo Mbeki's letter to worldwide leaders, expressing his concern about the situation faced by his country over the spread of AIDS. Mbeki's desire to see the situation approached in the most rigorous scientific way possible; Concern over Mbeki's alleged giving of more weight to some voices than the scientific process justifies.

Recent re-evaluations of the geological record of the earliest life on Earth have led to the suggestion that some of the oldest putative microfossils and carbonaceous matter were formed through abiotic hydrothermal processes. Similarly, many early Archaean (more than 3,400-Myr-old) cherts have been reinterpreted as hydrothermal deposits rather than products of normal marine sedimentary processes. Here we present the results of a field, petrographic and geochemical study testing these hypotheses for the 3,416-Myr-old Buck Reef Chert, South Africa. From sedimentary structures and distributions of sand and mud, we infer that deposition occurred in normal open shallow to deep marine environments. The siderite enrichment that we observe in deep-water sediments is consistent with a stratified early ocean. We show that most carbonaceous matter was formed by photosynthetic mats within the euphotic zone and distributed as detrital matter by waves and currents to surrounding environments. We find no evidence that hydrothermal processes had any direct role in the deposition of either the carbonaceous matter or the enclosing sediments. Instead, we conclude that photosynthetic organisms had evolved and were living in a stratified ocean supersaturated in dissolved silica 3,416?Myr ago. [ABSTRACT FROM AUTHOR]

Reports on the potential impact of a 1996 South African government white paper on science and technology. The major organizational changes that will take place; The attempt to secure a more effective distribution of the science vote; The three major policy changes being proposed; The responsibilities of a National Research Foundation (NRF); The creation of a National Innovation Fund (NIF); The regular review of the country's seven science councils; The 1997 allocation.

Discusses the problem of allocating funding for scientific research in South Africa, following its ending of apartheid. The country's determination to forge a modern industrial economy; The white paper that sets out proposals for reorganizing; A report from the National Commission on Higher Education; The need to distribute more effectively among the seven research councils.

Reports that Dirk du Plessis and Kallie Landauer of the University of Pretoria in South Africa, who claimed to have discovered a cure for AIDS, were reprimanded by a university disciplinary committee in July 1997. Both to retain their posts.

The article offers world news briefs from February 24, 2012 to March 1, 2012. The U.S. Department of Health and Human Services has introduced a draft action plant aimed at treatment and prevention of Alzheimer's disease in 2025. The Institute of Science and Technology in Austria has secured funding from Austrian provincial and federal government. South African and American researchers have revealed an initiative aimed at collection and integration of data on farming practices and ecosystems.

The author reflects on the international negotiations on global warming that will be reopen in Durban, South Africa in November 2011. The author says that environmental campaigners at the United Nations (UN) climate summits will correct anyone who claimed that the Kyoto Protocol will expire in 2012. The author also mentions that one of the goal of Kyoto is to form and test an international architecture for the reduction of greenhouse-gas emissions and its scaling.

A letter to the editor in response to an article related to South America's research impact underestimated in the main citation databases published in previous issue in 2014 is presented.

The article offers information on the 38th Union World Conference on Lung Health held in Cape Town, South Africa. It discusses the move of health authorities to respond to the combination of HIV and tuberculosis (TB) including multiple-drug resistance to TB. According to the report from the U.S. Centers for Disease Control and Prevention, one-third of TB patients are unaware of their HIV status, while 9% of those with TB are HIV positive. It also discusses the importance of co-infection of HIV and TB which has been emerging specifically in the country during the early stage of AIDS pandemic.

The article reports on the plan of South African Government to adopt a comprehensive strategy for managing the country's Acquired Immune Deficiency Syndrome (AIDS) epidemic. The plan, which was endorsed by the South African National AIDS Council on April 30, 2007, lays out proposals to cut infection rates and improve diagnosis of the diseases. However, a lack of trained doctors and nurses is a serious constraint on the full implementation of the strategic plan.

After a decade of democratic government in South Africa, the face of research remains largely untransformed. Published research has declined significantly in relation to global output, and spending on research and development has declined as a proportion of gross domestic product. White scientists still produce more than 90 percent of research articles published. Moreover, the research community is ageing, with almost half of authors of research articles now being over 50. Very few able school-leavers are being attracted into research careers and only a tiny proportion of black scholars leave school with university-entrance qualifications in mathematics and physical science.

Comments on the so-called Durban Declaration, which states that HIV is the cause of AIDS disease. How the declaration was a response to debates in South Africa which questioned the role of HIV in AIDS; Why `Nature' magazine endorses the Durban Declaration; Why South Africa's Thabo Mbeki should reconsider his view about the cause of AIDS.