1,460 research outputs found
A Geospatial Analysis of CDC-funded HIV Prevention Programs for African Americans in the United States
Given the increase in HIV/AIDS infection rates among racial and ethnic minorities, particularly African Americans, this study was undertaken as part of a larger research effort to examine the distribution of HIV prevention services focusing on African American populations within the United States. Data were gathered via a national survey of community-based organizations (CBOs) funded by the Centers for Disease Control and Prevention (CDC). A geocoded national database was constructed to identify, locate, and map these HIV prevention programs. A total of 1,020 CBOs responded to the survey, yielding a response rate of 70.3%. These CBOs administered a total of 3,028 HIV prevention programs. Data describing intervention types and persons served, combined with the address and service area of responding CBOs, were integrated with census data (2000) and analyzed by using a geographic information system (GIS). The results of our national level analysis show that HIV prevention services for African Americans have fair coverage where African Americans comprise a substantial proportion of the population in urban areas in northeastern states, but that HIV prevention services for African Americans are inadequately distributed in the southeastern states. A local-level analysis was conducted for Alabama, where 68% of HIV/AIDS cases are among African Americans. Specific interventions such as street and community outreach, health communications, and public information are fairly well provided to African Americans in more urban cities in Alabama, however, individual- and group-level interventions have poor coverage in rural areas where a large percentage of African-Americans live. Overall, our study illustrates that the use of GIS adds value when used with other data sources to provide prevention services that are accessible to the populations most in need
Transformative treatments
Contemporary social-scientific research seeks to identify specific causal mechanisms for outcomes of theoretical interest. Experiments that randomize populations to treatment and control conditions are the âgold standardâ for causal inference. We identify, describe, and analyze the problem posed by transformative treatments. Such treatments radically change treated individuals in a way that creates a mismatch in populations, but this mismatch is not empirically detectable at the level of counterfactual dependence. In such cases, the identification of causal pathways is underdetermined in a previously unrecognized way. Moreover, if the treatment is indeed transformative it breaks the inferential structure of the experimental design. Transformative treatments are not curiosities or âcorner cases,â but are plausible mechanisms in a large class of events of theoretical interest, particularly ones where deliberate randomization is impractical and quasi-experimental designs are sought instead. They cast long-running debates about treatment and selection effects in a new light, and raise new methodological challenges.PostprintPeer reviewe
Assessing cellular response to functionalized α-helical peptide hydrogels
α-Helical peptide hydrogels are decorated with a cell-binding peptide motif (RGDS), which is shown to promote adhesion, proliferation, and differentiation of PC12 cells. Gel structure and integrity are maintained after functionalization. This opens possibilities for the bottom-up design and engineering of complex functional scaffolds for 2D and 3D cell cultures.</p
A review of evidence for bystander intervention to prevent sexual and domestic violence in universities
This literature review is intended to be useful to a range of audiences.The 3 aims of the review are to:- set out the rationale for using a bystander approach in sexual and domestic violence prevention work at English universities- verify that all current evidence for best practice has been assimilated in the preparation of âThe intervention initiativeâ toolkit for English universities, commissioned by PHE and developed by the research team undertaking the review- bring interested parties up to date with the most recent research relating to bystander intervention methods for addressing sexual and domestic violence in university settingsIt builds on the review of bystander approaches in support of preventing violence against women published in 2011 (Powell, 2011) which summarised the evidence-based features for effective bystander approaches in support of preventing violence against women
Synthesis, Structure and CVD Studies of the Group 13 Complexes [Me<sub>2</sub>M{tfacnac}] [M = Al, Ga, In; Htfacnac = F<sub>3</sub>CC(OH)CHC(CH<sub>3</sub>)NCH<sub>2</sub>CH<sub>2</sub>OCH<sub>3</sub>]
A family of group 13 metal dimethyl complexes of the general form [Me2M{ MeC(O)CHC(NCH2CH2OMe)CF3}] (M = Al (2), Ga (3) or In (4)) have been synthesised by reaction of the isolated free ligand (1) with the corresponding trimethyl-metal reagents. The isolated complexes (2-4) were characterised by elemental analysis, NMR spectroscopy, and the molecular structures of the complexes were determined by single crystal X-ray diffraction which reveals the compounds to be monomeric 5 coordinate complexes with coordination of the pendent ether bearing lariat in the solid state. Thermogravimetric analysis showed complexes 2-4 all to have residual masses, at 200 °C, of 2.4% or less well below the value for the respective metal oxides, and vapour pressure measurements show the indium complex (4) to be an order of magnitude less volatile (0.09 Torr at 80 oC) than the Al (2) or Ga (3) derivatives despite being isoleptic systems. Complexes 2-4 have all been investigated for their utility in the LP-MOCVD growth of the respective metal oxides in the absence of additional oxidant at 400 °C on silicon substrates
Chiral properties of SU(3) sextet fermions
SU(3) gauge theory with overlap fermions in the 2-index symmetric (sextet)
and fundamental representations is considered. A priori it is not known what
the pattern of chiral symmetry breaking is in a higher dimensional
representation although the general expectation is that if two representations
are both complex, the breaking pattern will be the same. This expectation is
verified for the sextet at N_f = 0 in several exact zero mode sectors. It is
shown that if the volume is large enough the same random matrix ensemble
describes both the sextet and fundamental Dirac eigenvalues. The number of zero
modes for the sextet increases approximately 5-fold relative to the fundamental
in accordance with the index theorem for small lattice spacing but zero modes
which do not correspond to integer topological charge do exist at larger
lattice spacings. The zero mode number dependence of the random matrix model
predictions correctly match the simulations in each sector and each
representation.Comment: 38 pages (12 pages text and gazillion tables/figures), minor
modification, references adde
Dietary Manipulation for Therapeutic Effect in Prostate Cancer
Given that there is a wealth of literature on the potential effect of a wide variety of phytochemicals on the growth of prostate cancer cells, we have limited our discussion to arguably four of the most important: isoflavones, lycopene, resveratrol, and curcumin. The focus of this review is on the clinical pharmacology of these compounds, as there are already an extensive number of reviews in the literature on all of these compounds for various cancers, including our previous review of isoflavones in prostate cancer (de Souza et al., 2009). Here, we use the loose term âphytochemicalsâ to describe this group of plantâbased compounds with biological activity in vitro, for simplicity. Like other phytochemicals, isoflavones, lycopene, resveratrol and curcumin have a wide variety of potential mechanisms of action in many different cancer cell lines. Many of these biological effects involve key components of signal transduction pathways within cancer cells, but in this review, we will be focusing on studies specifically in prostate cancer
The effect of direct and indirect heat treatment on the attributes of whey protein beverages
peer-reviewedThermal processing of ready-to-drink high protein beverages can have a substantial impact on the physical and sensory properties of the final product for long-life milks such as extended shelf life and ultra high temperature processed products. Direct and indirect heat treatment technologies were applied to whey protein isolate (WPI) -based beverages containing 4, 6 or 8% (w/w) protein. Lower levels of protein denaturation (66â94%) were observed using direct heating compared with indirect heating (95â99%) across protein levels and heating temperatures (121 and 135 °C final heat). Direct heat treatment resulted in significantly lower viscosity and less extensive changes to the volatile profile, compared with indirect heat treatment. Overall, the application of direct and indirect heat treatment to WPI solutions resulted in significantly different final products in terms of appearance, physical characteristics and volatile profile, with direct heating resulting in many enhanced properties compared with conventional indirect heat treatment
Histotripsy of Rabbit Renal Tissue in Vivo: Temporal Histologic Trends
Background and Purpose: Histotripsy is defined as noninvasive, nonthermal, mechanical (cavitational) tissue ablation. We previously demonstrated the predictable acute tissue effects of histotripsy in rabbit kidney and other tissues. We sought to characterize the appearance and natural history of renal tissue after histotripsy. Materials and Methods: Following Institutional Animal Care Committee approval, the left kidneys of 29 rabbits were treated with 60,000 750-kHz, 15-cycle bursts of ultrasound energy from an 18-element phased-array transducer at a 1-kHz pulse-repetition frequency. The treated kidneys were harvested at 0, 1, 2, 7, 21, or 60 days; fixed in Formalin; then prepared for microscopic analysis with hematoxylin and eosin and trichrome stains. Results: For kidneys harvested acutely (day 0), a contiguous area of finely disrupted tissue was observed containing no recognizable cells or cellular components. Along the boundary of architectural disruption, a border several tubules wide contained cells that were not visibly disrupted but appeared damaged (pyknotic nuclei). At subsequent time intervals, an inflammatory response developed in association with a steadily decreasing area of cellular and architectural disruption. By day 60, only a small fibrous scar persisted adjacent to a wedge of tubular dilation and fibrosis underlying a surface-contour defect. Conclusions: Histotripsy produces mechanical fractionation of cellular and architectural structures. The resultant acellular material appears to be readily reabsorbed within 60 days in the rabbit. This may prove to be a significant advantage for imaging assessment of residual tumor after ablation of renal malignancy.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63123/1/end.2007.9915.pd
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