Mobile hydrocarbon microspheres from >2-billion-year-old carbon-bearing seams in the South African deep subsurface.

By ~2.9 Ga, the time of the deposition of the Witwatersrand Supergroup, life is believed to have been well established on Earth. Carbon remnants of the microbial biosphere from this time period are evident in sediments from around the world. In the Witwatersrand Supergroup, the carbonaceous material is often concentrated in seams, closely associated with the gold deposits and may have been a mobile phase 2 billion years ago. Whereas today the carbon in the Witwatersrand Supergroup is presumed to be immobile, hollow hydrocarbon spheres ranging in size from <1 µm to >50 µm were discovered emanating from a borehole drilled through the carbon-bearing seams suggesting that a portion of the carbon may still be mobile in the deep subsurface. ToF-SIMS and STXM analyses revealed that these spheres contain a suite of alkane, alkenes, and aromatic compounds consistent with the described organic-rich carbon seams within the Witwatersrand Supergroup's auriferous reef horizons. Analysis by electron microscopy and ToF-SIMS, however, revealed that these spheres, although most likely composed of biogenic carbon and resembling biological organisms, do not retain any true structural, that is, fossil, information and were formed by an abiogenic process.

Stars of the terrestrial deep subsurface: a novel 'star-shaped' bacterial morphotype from a South African platinum mine.

We study structure and function. Credit of course, goes to TJB, for it is from him that I inherited the habit of personifying bacteria and attempting to think like a bacterium, to better understand what they do. This work has taken us to wonderful places such as Yellowstone National Park, The Canadian Arctic, Australia, and the deep subsurface in the Republic of South Africa, the subject of this manuscript. From their perspective, why they do what they do is simple, to live. How they do it, is more challenging for us to understand, so it is something that we continue to work on. The marvel of bacteria is something that I, in turn, try to pass on to my students where I hope it will find fertile ground and provide as much enjoyment as it has given me - G. Southam. A biofilm (mine-slime) collected from the Northam Platinum mine in the Republic of South Africa contained a new bacterial morphotype. Mine-slimes are generally considered to be microbiologically compromised, subsurface samples due to the likelihood of contamination from the mining environment. However, careful examination of this biofilm demonstrated that it possessed a diverse bacterial population that included organisms that are consistent with the deep subsurface, suggesting that mine-slimes represent an underutilized, 'natural' bacterial enrichment. Using scanning and transmission electron microscopy, a novel, branching, filamentous, star-shape bacterium (in cross section) has been found, adding a new bacterial morphotype and strategy that bacteria have demonstrated to increase their surface area to volume ratio.

Gunshot injuries in Mobile County, Alabama: 1985-1987.

Although much information about firearm fatalities has been published, few articles have characterized all types of gunshot victims, the weapons used, and the injuries sustained in a well-defined geopolitical unit. This study of 597 persons sustaining gunshot injuries serious enough to cause death or hospitalization in Mobile County Alabama during 1985-1987, addresses that deficit. The overall rate of these 597 seriously gunshot-injured victims was 53/100,000 population per annum. Of the 597 victims, 215 died, resulting in a rate of 18.9 per 100,000 population per annum. Demographic characteristics of the homicide victims, predominantly young black men, and the suicide victims, predominantly middle-aged and elderly white men, are similar to those reported from other parts of the country. Assault victims accounted for the largest (316) number of victims: again, young black men also constituted the largest demographic group among assault victims. Handguns accounted for 71% of the weapons used. No assault type weapons were employed. Head, neck, and chest wounds led with the greatest fatality rates. Information about nonfatally wounded victims, particularly data about the weapons, proved difficult to obtain. This was one of the many problems encountered in this type of project and, consequently, is discussed at some length. Additional population-based studies using prospective methods and a variety of investigators, including persons knowledgeable of firearms, are needed.

Knee contractures as the presenting manifestation of scleroderma.

Musculoskeletal disorders may be the primary manifestations of scleroderma. The case is reported of a patient admitted for an evaluation of severe knee flexion contractures who was diagnosed as having scleroderma but lacked the typical presenting features of the disease. Radiographic, serological, and histological support for this diagnosis are presented. Scleroderma should be considered in the diagnostic evaluation of joint contractures.

Xanthogranulomatous colloid cyst of the third ventricle.

This is a case report of a xanthogranulomatous colloid cyst of the 3rd ventricle. Possible etiologies for this rare entity, along with the clinical problems that may be associated with it, and the differential diagnosis are discussed.