Designing HIV/AIDS Intervention Studies: An Operations Research Handbook

This handbook has several objectives and uses. First, it is designed to help HIV/AIDS researchers develop and write a detailed operations research proposal. An appropriate use of the handbook is as a resource in workshops or courses on research design and proposal development. Thus, the organization of the handbook follows that of a research proposal, starting with identifying, defining, and justifying a research problem, and ending with how to prepare a budget. Although the handbook is not an academic textbook on research methods, it does provide a review of many key concepts and important methods essential for conducting HIV/AIDS field research studies. These features can also help HIV/AIDS program administrators and managers as well as health policymakers understand the process of operations research and the uses of research findings to improve HIV/AIDS service delivery. Most examples were drawn from HIV/AIDS operations research studies conducted in Africa, Asia, and Latin America by the Horizons program, a global HIV/AIDS operations research program funded by USAID and implemented by the Population Council

Assessment of the Role of Renal Organic Anion Transporters in Drug-Induced Nephrotoxicity

In the present review we have attempted to assess the involvement of the organic anion transporters OAT1, OAT2, OAT3, and OAT4, belonging to the SLC22 family of polyspecific carriers, in drug-induced renal damage in humans. We have focused on drugs with widely recognized nephrotoxic potential, which have previously been reported to interact with OAT family members, and whose underlying pathogenic mechanism suggests the participation of tubular transport. Thus, only compounds generally believed to cause kidney injury either by means of direct tubular toxicity or crystal nephropathy have been considered. For each drug, or class of agents, the evidence for actual transport mediated by individual OATs under in vivo conditions is discussed. We have then examined their role in the context of other carriers present in the renal proximal tubule sharing certain substrates with OATs, as these are critical determinants of the overall contribution of OAT-dependent transport to intracellular accumulation and transepithelial drug secretion, and thus the impact it may have in drug-induced nephrotoxicity

Lake Chautauqua Fish Production Study, 1997

Progess ReportReport issued on: February 1999INHS Technical Report prepared for Rock Island District, U.S. Army Corps of Engineer

Progress Report: Lake Chautauqua Fish Production Study, 1998

Progress ReportReport issued on: December 1999INHS Technical Report prepared for US Army Corps of Engineers, Rock Island Distric

Upper Thermal Tolerances of Two Native and One Invasive Crayfish in Missouri, USA

The spread of invasive crayfish requires invaded habitats to be thermally suitable, and differences in thermal tolerances among species could provide thermal refugia for native crayfish affected by the invader. We estimated upper thermal tolerances for the invasive Faxonius hylas and native F. peruncus and F. quadruncus in Missouri, USA, using critical thermal maxima (CTmax) methodology to determine if there were ecologically exploitable differences in estimates among species and if areas within their distributional ranges exceed their thermal maximums. Estimates of CTmax did not differ among species or sexes but differed among groups acclimated to different temperatures. Additionally, crayfish size had a small, yet significant effect on CTmax estimates with smaller crayfish having lower CTmax estimates than larger crayfish. The similarity among CTmax estimates indicates that for at least upper thermal tolerance, areas thermally available to the native species will also be thermally suitable for the invader. We did not observe water temperatures in the field that exceeded CTmax estimates for any species. However, areas within the mainstem St. Francis River did have warming tolerance estimates of less than 5°C, indicating that establishment of the invader in the mainstem could be limited by water temperature

Differing effects of suspended sediment on the performance of native and exotic Daphnia

Although large cladocerans are usually uncommon in large rivers, Daphnia lumholtzi (an exotic species in North America) is widespread and occasionally abundant. We collected zooplankton on the Illinois River (Illinois, U.S.A.) in 1995 and 1996 and found that the peak density of D. lumholtzi (25 L1) typically exceeded that of all native species combined. Maximum density occurred during warm periods (up to 27°C) when concentrations of inorganic suspended sediments were high (\u3e50mg L-1). Using a life table experiment, we examined the effects of variation in suspended sediment (0 and 80mg L-1) and food (104 and 105 Ankistrodesmus cells mL-1) on fitness of D. lumholtzi and the native Daphnia parvula. Daphnia lumholtzi had greater survivorship than D. parvula in most treatments and higher life‐time fertility than D. parvula in all treatments. Both species achieved their fastest intrinsic rates of growth in treatments with high food, but their responses to suspended solids differed. The growth rate of D. lumholtzi in high food was slightly increased by higher turbidity, whereas that of D. parvula was depressed. Results suggest that the ability of D. lumholtzi to tolerate suspended solids is an important factor contributing to its success in invading North American rivers

Novel technique to identify large river host fish for freshwater mussel propagation and conservation

Skipjack Herring (Alosa chrysochloris) has long been proposed as the sole host for Reginaia ebenus (Ebonyshell) and Elliptio crassidens (Elephantear), but these relationships were unconfirmed because of difficulties with maintaining this fish species in captivity. We confirmed the suitability of Skipjack Herring as host for both mussel species, and we also showed that Alabama Shad (Alosa alabamae) is an additional suitable host for E. crassidens; both fish species produced large numbers of juvenile mussels. No other fish species tested (n = 12) were suitable hosts for either mussel species. Our results, combined with results from other studies, suggest these mussel species are specialists on genus Alosa. Traditional methods for host identification were problematic for herrings because of their sensitivity to handling and the large volumes of water required to maintain them in captivity. In addition to traditional methods, we confirmed the suitability of these fishes as hosts using a novel technique in which fish gills infected with glochidia were excised from sacrificed fishes and held in recirculating holding tanks with flow until metamorphosis was complete. Completion of metamorphosis on excised gills required glochidia spend at least 11–17 d encapsulated on live fishes before gill excision. This technique may be useful for other large or sensitive fishes that do not lend themselves well to traditional methods for host identification. Confirmation of Alosa spp. as primary hosts for R. ebenus and E. crassidens supports the idea that dams and other river modifications that disrupt migrations of these fishes are key factors in the range restrictions of these mussel species

Thermal Tolerance of the Piedmont Blue Burrower Cambarus harti and Sympatric Native and Invasive Crayfish Species of the Southeastern United States

The southeast United States is the epicenter of global crayfish biodiversity, but these species are among some of the most threatened in the world. Life history and biological trait data deficiencies, particularly of burrowing crayfish species, hampers efforts for accurately assessing imperilment rates and informing conservation efforts. Rising temperatures are a threat to aquatic ectotherms and it is important to evaluate crayfish tolerances to determine if they are at or near their upper thermal limits. We conducted dynamic temperature ramps to evaluate the temperatures at which ecological death (critical thermal maximum; CTM) and physiological death (upper thermal limit; UTL) occurred for the imperiled and narrowly endemic primary burrower Cambarus harti and three common, sympatric species C. latimanus, C. striatus, and Procambarus clarkii. All species differed in CTM with C. latimanus being the most sensitive (35.0°C), C. striatus (37.0°C) and C. harti (37.8°C) having intermediate tolerance, and P. clarkii being the most tolerant (39.0°C). The UTL of all species ranged from 39.4 – 39.8°C. We found no evidence that C. harti, a rare primary burrower, will require more restrictive acute thermal guidelines for protection compared to more common sympatric secondary burrowers