661 research outputs found
Cardiovascular and hematopoietic responses to volatile benzene exposure.
The rapid and recent increase in the global epidemic of diabetes and cardiovascular disease suggests a strong component of the environment is contributing. Benzene is a ubiquitous volatile pollutant generated by cigarette smoke, automobile exhaust, wildfires and industrial activities. Consequently, it is found in almost all urban and rural air samples. Benzene is known to cause hematotoxicity and its metabolism generates oxidative stress. Although, benzene has been studied for many years, few investigations have probed what influence benzene exposure may have on other physiological processes. Here we hypothesize that benzene metabolism by hepatic-CYP450 2E1 generates oxidative stress and inflammation, which then promote insulin resistance and endothelial dysfunction. To test this hypothesis, we measured hematological progenitor differentiation and circulating blood cell types as well as indices of oxidative stress, vascular damage, insulin resistance and stem cell function to assess relative sensitivity of hematological and vascular biomarkers. Our findings show that benzene-exposed mice exhibit oxidative stress, inflammation, vascular damage, insulin resistance, thrombosis with diminished vascular repair capacity at levels similar to hematological changes typically found in acute studies assaying for the lowest observed adverse effect level. These data suggest that individuals exposed to this ubiquitous air pollutant are likely to experience inflammation and vascular complications
Respect for Nature: A Theory of Environmental Ethics
Paul Taylor’s Respect for Nature was first published 1986 when environmental ethics was a relatively new field. In it he defended a deontological biocentric environmental ethic predicated on the idea that all living beings have inherent value. It was a groundbreaking work in non-anthropocentric ethics, and since then it has been frequently anthologized and used in ethics and environmental philosophy courses taught around the world. The Twenty-fifth Anniversary Edition of Respect for Nature (2011) contains a two-page forward by Dale Jamieson, who notes the continued urgency for intellectuals to consider the meaning of “respect for nature.” When Respect for Nature was first published, most professional ethicists were unclear on how to think about our moral duties to the non-human world. Taylor has provided us a unique way of thinking about such matters that is still relevant today
Preferential Treatment and the Demands of Fair Competition
The issue of the fairness of many current affirmative action policies stands in a necessary juxtaposition with the relationship citizens have with each other in the U.S. free enterprise system. Although it is the case that many of today\u27s affirmative action programs that involve preferential treatment are flawed and morally unjustified as they stand, it is not the case that no strong affirmative action policy is morally justified. By appealing to historical facts and basic intuitions about fair competition, I present a cogent counterfactual argument that suggests that, due to the competitive nature of our present society, some forms of affirmative action are necessary to make the assumed background institutions of our society fair. Specifically, affirmative action policies that involve preferential treatment should be managed on a case-by-case basis by considering the life and family history of each candidate. Although cumbersome, this approach would be one of the fairest ways to comply with the reasonable demands of compensatory justice
Genetic variation of blood groups in inbred lines of Leghorns, derived from a common base population
Nine inbred lines of White Leghorn chickens were developed by continued brother X sister mating over 10 generations. Initial matings were made in 1968 by selecting at random full sibs within each of two outbred lines of White Leghorns, which themselves had been selected since 1960 from a single population for high and low egg weight, respectively. A third base population for inbred lines consisted of a cross between the two selected lines. Blood types for the A, B, E, C, D, H, I, K, L and P blood group systems were obtained for individuals belonging to nine surviving inbred lines in 1977. All systems showed differences between lines attesting to the diverse genetic origin of the initial 1960 population that was based on eight different breeding flocks. Among the nine inbred lines, three were found to segregate for a single system; two lines segregated for two systems; and three lines segregated for three systems. The ninth line (no 92) was found to be polymorphic for six of the blood group loci. The results agree with the assumption that none of the blood group systems by itself showed heterozygosity in excess of expectations for neutral genes. Intraline polymorphisms were in excess of neutral gene expectations only in one line in which substantial deviation from all other lines suggests that a recent pedigree error and not single-locus heterosis may be the source of its genetic variabilit
Using Lexical Analysis to Link Depression in Schizotypy
poster abstractIntroduction: Previous research has suggested that depression is a major symptom of
schizophrenia, and, moreover, schizotypy. Speech has also been heavily studied within the schizophrenia-spectrum. Compared to healthy populations, those with schizotypy tend to show greater depression and use negative affect (emotion) words more frequently. Speech containing negative affect words has also been shown to correlate with depression in both the healthy population and the schizophrenia-spectrum. This study aimed to examine any differences in depression level and negative affect words between a schizotypy and control sample, and also if depression level can be linked to speech within schizotypy.
Methods: 38 participants partook in an open-ended, semi-structured interview-25 making up the schizotypy group, and 13 in the non-schizotypy group. The interview was recorded, transcribed, and ran through Lexical Inquiry Word Count (LIWC), a computerized measure that evaluates speech content using a dictionary that contains over 4500 words/word stems across 68 categories. Participants were also administered two depression questionnaires.
Results: The schizotypy sample showed significantly greater depression than controls (p.05, d= -.54).Within schizotypy, a trend level relationship between depression and negative affect words was observed (r= -.31, p>.05).
Conclusion: These findings are consistent with previous studies reporting higher depression levels in the schizophrenia-spectrum compared to healthy populations. It is inconsistent, however, with regards to schizotypy and use of negative emotion words, which may be due in part to low power. Furthermore, this study shows that lexical analysis software has the potential to assist in the measurement of depression in schizotypy
Enhanced Integrin α4β1-Mediated Adhesion Contributes to a Mobilization Defect of Endothelial Progenitor Cells in Diabetes.
Diabetes is associated with a deficit of circulating endothelial progenitor cells (EPCs), which has been attributed to their defective mobilization from the bone marrow. The basis for this mobilization defect is not completely understood, and we sought to determine if hyperglycemic conditions enhanced EPC adhesion. We found that culturing EPCs in high glucose media increased adhesion to bone marrow stromal cells. This enhanced adhesion was associated with decreased expression of protein kinase A regulatory subunit 1β (PRKAR1β), activation of protein kinase A (PKA), and phosphorylation of α4-integrin on serine 988. This potentiated adhesion was reversed by treatment with a PKA inhibitor, overexpression of PRKAR1β, or expression of a phosphorylation-defective α4-integrin variant (α4[S988A]). Using a model of type 1 diabetes, we showed that α4(S988A)-expressing mice have more circulating EPCs than their wild-type counterparts. Moreover, diabetic α4(S988A) mice demonstrate enhanced revascularization after hind limb ischemia. Thus, we have identified a novel signaling mechanism activating PKA in diabetes (downregulation of an inhibitory regulatory subunit) that leads to deficits of circulating EPCs and impaired vascular repair, which could be reversed by α4-integrin mutation
Zusammenhänge von Off-Ice und On-Ice Leistungstests: Identifizierung relevanter Tests für die Leistungsdiagnostik im Eishockey
Cryogenic calorimeters in astro and particle physics
The development of cryogenic calorimeters was originally motivated by the
fact that very low energy thresholds and excellent energy resolutions can be
achieved by these devices. Cryogenic devices are widely used in double beta
decay experiments, in cosmological dark matter searches, in x-ray detection of
galactic and extragalactic objects as well as in cosmic background radiation
experiments. An overview of the latest developments is given.Comment: (28 pages, contribution to the VIII International Conference on
Calorimetry in High Energy Physics, 13-19 June 1999, Lisbon, Portugal
Light Neutralinos as Dark Matter in the Unconstrained Minimal Supersymmetric Standard Model
The allowed parameter space for the lightest neutralino as the dark matter is
explored using the Minimal Supersymmetric Standard Model as the low-energy
effective theory without further theoretical constraints such as GUT. Selecting
values of the parameters which are in agreement with present experimental
limits and applying the additional requirement that the lightest neutralino be
in a cosmologically interesting range, we give limits on the neutralino mass
and composition. A similar analysis is also performed implementing the grand
unification constraints. The elastic scattering cross section of the selected
neutralinos on Al and on other materials for dark matter experiments is
discussed.Comment: Submitted to Astroparticle Physics, 19 Feb. 96, Latex 23 pages with
24 figures in a gzip compressed file FIGURE.PS.GZ available via anonymous ftp
from ftp://iws104.mppmu.mpg.de/pub/gabutt
Advanced UVOIR Mirror Technology Development (AMTD) for Very Large Space Telescopes
ASTRO2010 Decadal stated that an advanced large-aperture ultraviolet, optical, near-infrared (UVOIR) telescope is required to enable the next generation of compelling astrophysics and exoplanet science; and, that present technology is not mature enough to affordably build and launch any potential UVOIR mission concept. AMTD builds on the state of art (SOA) defined by over 30 years of monolithic & segmented ground & space-telescope mirror technology to mature six key technologies. AMTD is deliberately pursuing multiple design paths to provide the science community with op-tions to enable either large aperture monolithic or segmented mirrors with clear engineering metrics traceable to science requirements
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