1,176 research outputs found

    Exhaled nitric oxide in ethnically diverse highâ altitude native populations: A comparative study

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    ObjectivesAndean and Tibetan highâ altitude natives exhibit a high concentration of nitric oxide (NO) in the lungs, suggesting that NO plays an adaptive role in offsetting hypobaric hypoxia. We examined the exhaled NO concentration as well as partial pressure of several additional highâ altitude native populations in order to examine the possibility that this putative adaptive trait, that is, high exhaled NO, is universal.MethodsWe recruited two geographically diverse highland native populations, Tawang Monpa (TM), a Tibetan derived population in Northâ Eastern India (n = 95, sampled at an altitude of ~3,200â m), and Peruvian Quechua from the highland Andes (n = 412). The latter included three distinct subgroups defined as those residing at altitude (Qâ HAR, n = 110, sampled at 4,338â m), those born and residing at seaâ level (Qâ BSL, n = 152), and those born at altitude but migrant to seaâ level (Qâ M, n = 150). In addition, we recruited a referent sample of lowland natives of European ancestry from Syracuse, New York. Fraction of exhaled NO concentrations were measured using a NIOX NIMO following the protocol of the manufacturer.ResultsPartial pressure of exhaled nitric oxide (PENO) was significantly lower (pâ <â .05) in both highâ altitude resident groups (TM = 6.2â ±â 0.5 nmHg and Qâ HAR = 5.8â ±â 0.5 nmHg), as compared to the groups measured at sea level (USA = 14.6â ±â 0.7 nmHg, Qâ BSL = 18.9â ±â 1.6 nmHg, and Qâ M = 19.2â ±â 1.7 nmHg). PENO was not significantly different between TM and Qâ HAR (pâ <â .05).ConclusionIn contrast to previous work, we found lower PENO in populations at altitude (compared to seaâ level) and no difference in PENO between Tibetan and Andean highland native populations. These results do not support the hypothesis that high nitric oxide in human lungs is a universal adaptive mechanism of highland native populations to offset hypobaric hypoxia.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151909/1/ajpa23915.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151909/2/ajpa23915_am.pd

    Realism, Objectivity, and Evaluation

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    I discuss Benacerraf's epistemological challenge for realism about areas like mathematics, metalogic, and modality, and describe the pluralist response to it. I explain why normative pluralism is peculiarly unsatisfactory, and use this explanation to formulate a radicalization of Moore's Open Question Argument. According to the argument, the facts -- even the normative facts -- fail to settle the practical questions at the center of our normative lives. One lesson is that the concepts of realism and objectivity, which are widely identified, are actually in tension

    Peer review quality and transparency of the peer-review process in open access and subscription journals

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    BACKGROUND:Recent controversies highlighting substandard peer review in Open Access (OA) and traditional (subscription) journals have increased the need for authors, funders, publishers, and institutions to assure quality of peer-review in academic journals. I propose that transparency of the peer-review process may be seen as an indicator of the quality of peer-review, and develop and validate a tool enabling different stakeholders to assess transparency of the peer-review process. METHODS AND FINDINGS:Based on editorial guidelines and best practices, I developed a 14-item tool to rate transparency of the peer-review process on the basis of journals' websites. In Study 1, a random sample of 231 authors of papers in 92 subscription journals in different fields rated transparency of the journals that published their work. Authors' ratings of the transparency were positively associated with quality of the peer-review process but unrelated to journal's impact factors. In Study 2, 20 experts on OA publishing assessed the transparency of established (non-OA) journals, OA journals categorized as being published by potential predatory publishers, and journals from the Directory of Open Access Journals (DOAJ). Results show high reliability across items (α = .91) and sufficient reliability across raters. Ratings differentiated the three types of journals well. In Study 3, academic librarians rated a random sample of 140 DOAJ journals and another 54 journals that had received a hoax paper written by Bohannon to test peer-review quality. Journals with higher transparency ratings were less likely to accept the flawed paper and showed higher impact as measured by the h5 index from Google Scholar. CONCLUSIONS:The tool to assess transparency of the peer-review process at academic journals shows promising reliability and validity. The transparency of the peer-review process can be seen as an indicator of peer-review quality allowing the tool to be used to predict academic quality in new journals

    Dialetheism in Action: A New Strategy for Solving the Equal Validity Paradox

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    This paper starts from the Equal Validity Paradox, a paradoxical argument connected to the so-called phenomenon of faultless disagreement. It is argued that there are at least six strategies for solving the paradox. After presenting the first five strategies and their main problems, the paper focuses on the sixth strategy which rejects the assumption that every proposition cannot be both true a false. Dialetheism is the natural candidate for developing strategy six. After presenting strategy six in detail, we formulate a normative problem for the dialetheist and offer a tentative solution to it. We then elaborate further considerations connecting strategy six to pluralism about truth and logic. Even if strategy six is a hard path to take, its scrutiny highlights some important points on truth, logic and the norms for acceptance and rejection

    Single WRW_R Production in eee^-e^- Collisions at the NLC

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    Single WRW_R production in eee^-e^- collisions at the NLC can be used to probe the Majorana nature of the heavy neutrinos present in the Left-Right Symmetric Model below the kinematic threshold for their direct production. For colliders in the s=11.5\sqrt {s}=1-1.5 TeV range, typical cross sections of order 110fb1-10 fb are obtained, depending on the specific choice of model parameters. Backgrounds arising from Standard Model processes are shown to be small. This analysis greatly extends the kinematic range of previous studies wherein the production of an on-shell, like-sign pair of WRW_R's at the NLC was considered.Comment: 13pp, 3 figures (available on request), LaTex, SLAC-PUB-647

    bsγb \to s \gamma Decay in SU(2)L×SU(2)R×U(1)SU(2)_L \times SU(2)_R \times U(1) Extensions of the Standard Model

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    The rare radiative decay bsγb \to s \gamma is studied in SU(2)L×SU(2)R×U(1)SU(2)_L \times SU(2)_R \times U(1) extensions of the Standard Model. Matching conditions for coefficients of operators appearing in the low energy effective Hamiltonian for this process are derived, and QCD corrections to these coefficients are analyzed. The bsγb \to s \gamma decay rate is then calculated and compared with the corresponding Standard Model result. We find that observable deviations from Standard Model predictions can occur in SU(2)L×SU(2)R×U(1)SU(2)_L \times SU(2)_R \times U(1) theories for a reasonable range of parameter values.Comment: 17 pages with 5 figures not included but available upon request, CALT-68-1893, TUM-T31-52/9
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