2,521 research outputs found
Conservation of Hawaiian Lpbelioids - in Vitro and Molecular Studies
With over 25% of Hawai'i’s Campanulaceae already extinct and many more on the verge of extinction, research in the propagation and the genetics of the remaining populations is greatly needed. In vitro propagation of 58 Hawaiian Campanulaceae species were attempted, through in vitro germination, organogenesis, or micropropagation. More than 80% of the species received as seeds were successfully germinated. No differences in germination rate or percentage was found between immature and mature seeds. Leaf explants produced viable shoots in 43% of the species, and 29% of wild-collected bud explants were successfully grown into plants. RAPDs was used to detect variability of the seedling populations of two bottlenecked species, Cyanea asarifolia St. John (original wild population of 15 plants) and Delissea undulata ssp. undulata Gaud, (original wild population of one plant). DNA was extracted from each species using small amounts of leaf tissue produced in vitro and used for the RAPDs studies. No detectable variation was found within these populations (indicating the impoverished remaining genetic information). The value of in vitro propagation and molecular studies of reduced populations is discussed
Optical Fiber-Based Sensing of Strain and Temperature at High Temperature
In-line intensity-based and Fabry-Perot silica optical fiber sensors have been developed to measure strain and temperature at temperatures up to 1500°F. The intensity-based sensor is an air gap splice in which the gap spacing changes as the length of the sensor housing changes. Two silica multimode optical fibers are placed in a hollow silica tube so their ends are separated by an initial gap spacing. As the sensor is strained, the gap spacing varies, resulting in a predictable change in output intensity. The Fabry-Perot sensor uses both single-mode and multimode fibers which are axially aligned inside a similar hollow core fiber. The four percent reflections which occur at both the glass-air interface at the end of the input singlemode fiber and at the air-glass interface at the surface of the multimode fiber differ in phase by an amount proportional to the separation between the two fiber ends. As the sensor is strained, the separation distance between these fiber ends changes, and the output signal intensity varies due to the interference between the reflected signals
Remembering the forgotten non-communicable diseases
The forthcoming post-Millennium Development Goals era will bring about new challenges in global health. Low- and middle-income countries will have to contend with a dual burden of infectious and non-communicable diseases (NCDs). Some of these NCDs, such as neoplasms, COPD, cardiovascular diseases and diabetes, cause much health loss worldwide and are already widely recognised as doing so. However, 55% of the global NCD burden arises from other NCDs, which tend to be ignored in terms of premature mortality and quality of life reduction. Here, experts in some of these 'forgotten NCDs' review the clinical impact of these diseases along with the consequences of their ignoring their medical importance, and discuss ways in which they can be given higher global health priority in order to decrease the growing burden of disease and disability.MerckUniv Melbourne, Sch Populat & Global Hlth, Melbourne, Vic 3053, AustraliaUniv London Imperial Coll Sci Technol & Med, St Marys Hosp, Dept Med, London W2 1NY, EnglandKEMRI Wellcome Trust Res Programme, Kilifi, KenyaUniv British Columbia, St Pauls Hosp, Vancouver, BC V6Z 1Y8, CanadaVA Med Ctr, Med Serv, Birmingham, AL USAVA Med Ctr, Ctr Surg Med Acute Care Res & Transit, Birmingham, AL USAUniv Alabama Birmingham, Sch Med, Dept Med, Birmingham, AL 35294 USAUniv Alabama Birmingham, Sch Publ Hlth, Div Epidemiol, Birmingham, AL 35294 USAMayo Clin, Coll Med, Dept Orthoped Surg, Rochester, MN 55905 USAUniv London Imperial Coll Sci Technol & Med, Natl Heart & Lung Inst, London, EnglandCtr Addict & Mental Hlth, Toronto, ON, CanadaTech Univ Dresden, D-01062 Dresden, GermanyUniv Toronto, Dalla Lana Sch Publ Hlth, Toronto, ON, CanadaUniv Toronto, Dept Psychiat, Toronto, ON, CanadaUofT, Inst Med Sci, Toronto, ON, CanadaNIDA, NIH, Rockville, MD USANIAAA, NIH, Bethesda, MD 20892 USAHosp Alemao Oswaldo Cruz, Inst Educ & Hlth Sci, BR-01323903 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Psychobiol, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Psychobiol, BR-04023062 São Paulo, BrazilWeb of Scienc
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Beyond the Diversity Audit: Uncovering Whiteness in Our Collections
In late 2020, a group of librarians at the University of Colorado Boulder (CU Boulder) came together to pursue the design of a diversity audit for monograph collections. After initial research and reflection, the authors realized that evaluating their existing collection on its racial or ethnic representation would not only be problematic, but also unnecessary, because it was clear to the authors that their collections are dominated by white voices and perspectives. How could they be otherwise? They were built for a primarily white audience as part of a system of knowledge production dominated by whiteness. The authors questioned whether the framework of a “diversity audit” really addressed their goal of a systematic anti-racist approach to collections management. This chapter details the authors’ process of rejecting the diversity audit framework for a large-scale review of monographs in a large academic library collection in the United States. It reviews the literature regarding diversity audits, as well as background on whiteness studies, as it leads to the authors’ rationale for instead developing a workbook for collection selectors. This workbook will position collection management practices within the white institutional presence (WIP) conceptual framework developed by scholar Diane Gusa (2010).</p
Amelioration of bleomycin-induced lung fibrosis in hamsters by dietary supplementation with taurine and niacin: biochemical mechanisms.
Interstitial pulmonary fibrosis induced by intratracheal instillation of bleomycin (BL) involves an excess production of reactive oxygen species, unavailability of adequate levels of NAD and ATP to repair the injured pulmonary epithelium, and an overexuberant lung collagen reactivity followed by deposition of highly cross-linked mature collagen fibrils resistant to enzymatic degradation. In the present study, we have demonstrated that dietary supplementation with taurine and niacin offered almost complete protection against the lung fibrosis in a multidose BL hamster model. The mechanisms for the protective effect of taurine and niacin are multifaceted. These include the ability of taurine to scavenge HOCl and stabilize the biomembrane; niacin's ability to replenish the BL-induced depletion of NAD and ATP; and the combined effect of taurine and niacin to suppress all aspects of BL-induced increases in the lung collagen reactivity, a hallmark of interstitial pulmonary fibrosis. It was concluded from the data presented at this Conference that the combined treatment with taurine and niacin, which offers a multipronged approach, will have great therapeutic potential in the intervention of the development of chemically induced interstitial lung fibrosis in animals and humans
Subjective response to alcohol and associated craving in heavy drinkers vs. alcohol dependents: An examination of Koob's allostatic model in humans
BACKGROUND: Koob's allostatic model of addiction emphasizes the transition from positive reinforcement to negative reinforcement as dependence develops. This study seeks to extend this well-established neurobiological model to humans by examining subjective response to alcohol (SR) as a biobehavioral marker of alcohol reinforcement. Specifically, this study examines (a) differential SR in heavy drinkers (HDs) vs. alcohol dependent individuals (ADs) and (b) whether HDs and ADs differ in terms of the association between SR and craving. METHODS: Data was culled from two alcohol challenge studies, totaling 91 participants (oversampled on OPRM1 Asp40 carriers). Alcohol was administered intravenously and participants completed standard measures of SR and craving at BrAC's of 0.02, 0.04, and 0.06 g/dl. SR was modeled as a multidimensional construct consisting of stimulation, sedation, and tension relief. RESULTS: ADs reported significantly higher sedation and craving initially and exhibited a blunted response to alcohol along escalating BrACs. ADs exhibited greater initial tension but did not differ from HDs in tension reduction across rising BrACs. Further, alcohol-induced stimulation was associated with alcohol craving to a significantly greater degree in HDs, as compared to ADs. CONCLUSIONS: This study provides initial evidence that HDs and ADs differ in their subjective experience of alcohol and in the association between dimensions of SR and craving for alcohol. Hypotheses derived from the allostatic model were partially supported, such that, while ADs and HDs did not differ on stimulation response, there was a relative dissociation between positive reinforcement and craving in ADs as compared to HDs
Characteristics of transposable element exonization within human and mouse
Insertion of transposed elements within mammalian genes is thought to be an
important contributor to mammalian evolution and speciation. Insertion of
transposed elements into introns can lead to their activation as alternatively
spliced cassette exons, an event called exonization. Elucidation of the
evolutionary constraints that have shaped fixation of transposed elements
within human and mouse protein coding genes and subsequent exonization is
important for understanding of how the exonization process has affected
transcriptome and proteome complexities. Here we show that exonization of
transposed elements is biased towards the beginning of the coding sequence in
both human and mouse genes. Analysis of single nucleotide polymorphisms (SNPs)
revealed that exonization of transposed elements can be population-specific,
implying that exonizations may enhance divergence and lead to speciation. SNP
density analysis revealed differences between Alu and other transposed
elements. Finally, we identified cases of primate-specific Alu elements that
depend on RNA editing for their exonization. These results shed light on TE
fixation and the exonization process within human and mouse genes.Comment: 11 pages, 4 figure
Assessing Internet addiction using the parsimonious Internet addiction components model - a preliminary study [forthcoming]
Internet usage has grown exponentially over the last decade. Research indicates that excessive Internet use can lead to symptoms associated with addiction. To date, assessment of potential Internet addiction has varied regarding populations studied and instruments used, making reliable prevalence estimations difficult. To overcome the present problems a preliminary study was conducted testing a parsimonious Internet addiction components model based on Griffiths’ addiction components (2005), including salience, mood modification, tolerance, withdrawal, conflict, and relapse. Two validated measures of Internet addiction were used (Compulsive Internet Use Scale [CIUS], Meerkerk et al., 2009, and Assessment for Internet and Computer Game Addiction Scale [AICA-S], Beutel et al., 2010) in two independent samples (ns = 3,105 and 2,257). The fit of the model was analysed using Confirmatory Factor Analysis. Results indicate that the Internet addiction components model fits the data in both samples well. The two sample/two instrument approach provides converging evidence concerning the degree to which the components model can organize the self-reported behavioural components of Internet addiction. Recommendations for future research include a more detailed assessment of tolerance as addiction component
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