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INNOVATION The COVID-19 pandemic has prevented in-person group medical visits. The underserved population at our federally qualified health center in Denver, Colorado was at heightened risk of food insecurity and [...]

Bacterial nanowires are extracellular appendages that have been suggested as pathways for electron transport in phylogenetically diverse microorganisms, including dissimilatory metal-reducing bacteria and photosynthetic cyanobacteria. However, there has been no evidence presented to demonstrate electron transport along the length of bacterial nanowires. Here we report electron transport measurements along individually addressed bacterial nanowires derived from electron-acceptor--limited cultures of the dissimilatory metal-reducing bacterium Shewanella oneidensis MR-1. Transport along the bacterial nanowires was independently evaluated by two techniques: (i) nanofabricated electrodes patterned on top of individual nanowires, and (ii) conducting probe atomic force microscopy at various points along a single nanowire bridging a metallic electrode and the conductive atomic force microscopy tip. The S. oneidensis MR-1 nanowires were found to be electrically conductive along micrometer-length scales with electron transport rates up to [10.sup.9]/s at 100 mV of applied bias and a measured resistivity on the order of 1 [OMEGA] x cm. Mutants deficient in genes for c-type decaheme cytochromes MtrC and OmcA produce appendages that are morphologically consistent with bacterial nanowires, but were found to be nonconductive. The measurements reported here allow for bacterial nanowires to serve as a viable microbial strategy for extracellular electron transport. bioelectronics | microbial fuel cells | bioenergy doi/ 10.1073/pnas.1004880107

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1523-1739.2009.01434.x Byline: THOMAS C. WANGER (*[dagger][double dagger][double dagger]), DJOKO T. ISKANDAR ([double dagger]), IRIS MOTZKE ([dagger]), BARRY W. BROOK (*), NAVJOT S. SODHI (s.**), YANN CLOUGH ([dagger]), TEJA TSCHARNTKE ([dagger]) Keywords: amphibians; Bayesian modeling; cacao agroforestry; Indonesia; land-use change; reptiles; Southeast Asia Abstract: Abstract: Little is known about the effects of anthropogenic land-use change on the amphibians and reptiles of the biodiverse tropical forests of Southeast Asia. We studied a land-use modification gradient stretching from primary forest, secondary forest, natural-shade cacao agroforest, planted-shade cacao agroforest to open areas in central Sulawesi, Indonesia. We determined species richness, abundance, turnover, and community composition in all habitat types and related these to environmental correlates, such as canopy heterogeneity and thickness of leaf litter. Amphibian species richness decreased systematically along the land-use modification gradient, but reptile richness and abundance peaked in natural-shade cacao agroforests. Species richness and abundance patterns across the disturbance gradient were best explained by canopy cover and leaf-litter thickness in amphibians and by canopy heterogeneity and cover in reptiles. Amphibians were more severely affected by forest disturbance in Sulawesi than reptiles. Heterogeneous canopy cover and thick leaf litter should be maintained in cacao plantations to facilitate the conservation value for both groups. For long-term and sustainable use of plantations, pruned shade trees should be permanently kept to allow rejuvenation of cacao and, thus, to prevent repeated forest encroachment. Abstract (Spanish): Efectos del Cambio de Uso de Suelo sobre la Composicion de la Comunidad de Anfibios y Reptiles en Sulawesi, Indonesia Resumen: Se conoce poco de los efectos del cambio de uso de suelo antropogenico sobre los anfibios y reptiles en los biodiversos bosques tropicales del sureste de Asia. Estudiamos un gradiente de modificacion de uso de suelo(bosque primario, bosque secundario, agrobosque de cacaco con sombra natural, agrobosque de cacao con sombra sembrada y areas abiertas) en Sulawesis central (Indonesia). Determinamos la riqueza de especies, abundancia, recambio y composicion de la comunidad en todos los tipos de habitat y las relacionamos con variables ambientales como la heterogeneidad del dosel y grosor de la capa de hojarasca. La riqueza de especies de anfibios disminuyo sistematicamente a lo largo del gradiente de modificacion del uso de suelo, pero la riqueza y abundancia de anfibios fue mayor en los agrobosques de cacao con sombra natural. Los patrones de riqueza y abundancia de especies en el gradiente de perturbacion fueron mejor explicados por la cobertura del dosel y el grosor de la hojarasca en anfibios y por la heterogeneidad y cobertura del dosel en reptiles. Los anfibios fueron afectados mas severamente que los reptiles por la perturbacion del bosque en Sulawesi. Para facilitar el valor de conservacion para ambos grupos, se debe mantener una cobertura de dosel heterogenea y una capa gruesa de hojarasca en las plantaciones de cacao. Para el uso a largo plazo y sustentable de plantaciones, permanentemente se deben mantener arboles de sombra podados para permitir el rejuvenecimiento del cacao y, por lo tanto, reducir presion sobre los bosques. Author Affiliation: (*)Environment Institute and School of Earth and Environmental Sciences, University of Adelaide, SA 5095, Australia ([dagger])Agroecology, University of Gottingen, 37073-Gottingen, Germany ([double dagger])Department of Biology, School of Life Sciences and Technology, Bandung, Indonesia (s.)Department of Biological Sciences, National University of Singapore, Singapore (**)Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, U.S.A. Article History: Paper submitted April 25, 2009; revised manuscript accepted September 8, 2009. Article note: [double dagger][double dagger]email thomas.wanger@adelaide.edu.au

Abstract: The mechanisms of gold precipitation by the interaction of cyanobacteria (Plectonema boryanum UTEX 485) and gold(III) chloride aqueous solutions (7.6 mmol/L final gold) have been studied at 25, 60, [...]

Alkaline, sulfidic, 4 to 53 million-year-old meteoric water emanating from a borehole intersecting quartzite-hosted fractures greater than 3.3 kilometer beneath the surface have supported a microbial community dominated by a bacterial species with Desulfotomaculum spp. and an archaeal species related to Methanobacterium spp. These geochemical setting and microbial communities are notably different from microbial ecosystems reported for shallower continental subsurface environments.

Tissue plasminogen activator (t-PA) may not be beneficial when treating patients in cardiac arrest, according to a study of 233 patients. t-PA breaks up blood clots and is usually used to treat a heart attack. Blood clots can also cause cardiac arrest.

The numerical simulations of the equilibrium profiles of liquid microstructures for various boundary conditions and geometrical surface patterns are presented. These computed profiles are compared with experimental profiles of glycerol on patterned wafers by using octadecyl -trichlorosilane (OTS).

The kinetic data obtained from the reflectivity technique consists of two stages in the photoinduced reaction process namely exponential law and the linear time dependence. When the reaction product layer is thick, the kinetic curve for the thermally stimulated process has a sublinear time dependence.

To the Editor: Routine vaccination of children with the 7-valent pneumococcal conjugate vaccine (PCV-7; Wyeth Pharmaceuticals, Collegeville, PA, USA), initiated in the United States in 2000, was followed within 2 [...]

Anabolic-androgenic steroids (AAS) are drugs that resemble testosterone, an androgen (male sex hormone). These agents were synthesized with the goal of developing drugs with the anabolic (muscle-building) effects, but not the androgenic effects, of testosterone. No steroids have yet been synthesized that have only anabolic effects. AAS are legitimately prescribed up to three million times per year in the US to treat certain anemias and gynecologic problems, to increase protein anabolism, and to aid the treatment of growth delay and osteoporosis. Nonmedically, AAS are used by body builders and others in good health to increase skeletal muscle size and strength. This usage has been condemned by many medical and sports organizations on the basis of fair play, known adverse effects, and unknown long-term effects. Although previously thought to be ineffective, AAS do increase muscle size and strength in people who are involved in physical training and consume a high-protein, high-calorie diet. Athletes who take AAS have reported improvements in their physical, mental and emotional states and appearance. The epidemiology of AAS use is discussed in this article, as are the sources of AAS. Adverse effects are described, including those on the liver, growth, and sexual characteristics. Research of the effects of AAS on fat metabolism, cardiovascular health, and tumor growth is underway. Efforts to limit nonmedical use have included legislative and legal initiatives and educational efforts by professional and medical groups. The AMA (American Medical Association) supports increased criminal penalties for nonprescribed AAS use, but does not favor classifying AAS as a controlled substance. The AMA continues to cooperate with other organizations in educating athletes and other users, and encourages research concerning the effects of AAS. (Consumer Summary produced by Reliance Medical Information, Inc.)

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections increased from 2000 to 2003 in hospitalized pediatric patients in Houston. CA-MRSA was associated with greater illness than was infection with methicillin-susceptible strains. Children [...]

A molecular approach is described to the control of both the length-scale of polymer/fullerene phase segregation and the electron mobility in the fullerene network. Bulk heterojunction solar cells are studied in order to understand how molecular control over fullerene-fullerene interactions might translate into a favorable BHJ morphology and thus improve electron mobility and photovoltaic device performance.

After decades of decline in developed countries, there was a resurgence of tuberculosis in the mid- 1980s accompanied by increased recognition that this infectious disease has long remained a major public health problem at the global level. New methods from molecular biology, in particular DNA `fingerprinting' (of Mycobacterium tuberculosis), made it clear that current transmission and recent infection (in contrast to reactivation of earlier, latent infection) were much more significant than previously believed. Studies of tuberculosis outbreaks using these new tools pointed to complex networks through which infection was spreading and highlighted the need for new approaches to outbreak investigation and disease control. In the study reported here a new approach -- combining methods from molecular biology, epidemiology and network analysis -- was used to examine an outbreak of tuberculosis in Houston, Texas. Initial investigation using conventional strategies revealed few contacts among 37 patients with identical (six-band) DNA (IS6110-based) fingerprints but subsequent research uncovered over 40 places (including many gay bars) to which patients in this outbreak could be linked. Network methods were used to reconstruct an outbreak network and to quantify the relative importance (here, `betweenness' centrality) of different actors (persons and places) playing a role in the outbreak. The multidisciplinary work provides the basis for a new approach to outbreak investigation and disease control. Keywords: Mycobacterium tuberculosis; DNA fingerprinting; Outbreak investigation; Network analysis; Outbreak network; Place-finding

Cocoa yields will be 75,000 tonnes short of those predicted for the 2013-14 growing season (see go.nature.com/ob6eyt). Supply deficits have been linked to extreme weather events in the cocoa-growing regions [...]