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Urbanization is a major contributor to habitat loss and fragmentation and is considered a global threat to biodiversity. We studied reptile and amphibian species diversity and abundance in a highly fragmented landscape adjacent to...
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Urbanization is a major contributor to habitat loss and fragmentation and is considered a global threat to biodiversity. We studied reptile and amphibian species diversity and abundance in a highly fragmented landscape adjacent to the second largest metropolitan area in the United States. Habitat patches in our study area were made up of remnant native vegetation surrounded by roads, housing, and other urban development. Species richness and diversity were positively associated with patch size, but patch age was not significantly associated with community characteristics. Four relatively common species were not detected in the small patches, indicating the possibility they had been extirpated by the time monitoring began, and six rarer species were not detected or detected only once in these patches. Although the patch size effect on species diversity was strong, we found that several of the small habitat patches had similar diversity to large patches, indicating potential value of these small habitat patches in protecting species as "microreserves." In addition, one lizard species was found to be significantly more abundant in the smaller patches. To determine if abundance changed over time, we compared capture rates for four common lizards at the same sites ten years later. For three of the four species, abundance decreased over that period, specifically in the small patches. Although our long-term monitoring has confirmed that the full suite of herpetofauna is currently preserved in the study area overall, declines even in the common species over time hint at the potential severity of the threat of urbanization to rare species.
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'It's warming. It's us. We're sure. It's bad. We can fix it.' Kim Nicholas (Lund University, Sweden) opened her talk with a reminder of the facts of anthropogenic climate change. Flying is a major contributor to carbon emissions, ...
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'It's warming. It's us. We're sure. It's bad. We can fix it.' Kim Nicholas (Lund University, Sweden) opened her talk with a reminder of the facts of anthropogenic climate change. Flying is a major contributor to carbon emissions, while also considered important for a successful academic career. The symposium brought together speakers from a range of disciplines (and locations through virtual participation) to discuss why flying is such a key part of academia, and how we might reduce or replace it.
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My entrance into a science career did not follow the typical pattern. Although, I have always had a love for science, I gave little thought to the pursuit of a graduate degree in science. I was a pre-medical student as an undergra...
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My entrance into a science career did not follow the typical pattern. Although, I have always had a love for science, I gave little thought to the pursuit of a graduate degree in science. I was a pre-medical student as an undergraduate and also an advance ROTC student at Virginia State College in Ettrick, VA. Upon graduation, the cost of medical school caused me to rethink my options and a career as an Army officer appeared rather attractive. I was commissioned a second lieutenant in the Army Medical Service Corps. Among my responsibilities in a unit that operated a pharmacy, I was involved in the training of enlisted men who worked in the pharmacy. Thus, I developed an interest in both physiology and pharmacology. Hence, after my four year tour was completed, I left the service and entered graduate school at Purdue Univ. to study physiology. My PhD research centered on the identification of the neurotransmitter involved in the regulation of the Limulus heart. In the course of my studies I became aware of a number of neurotransmitter studies ongoing in the Kravitz laboratory in the Department of Neurobiology at Harvard Medical School. I very much wanted to pursue postdoctoral studies in the Kravitz group. However, by now I had to be concerned with a growing family, a wife and three young children. A mentor of mine at Virginia State College (VSC) who had been following my progress at Purdue, contacted me with an offer as a full time faculty member at VSC. I felt it prudent to accept this faculty offer which paid considerably more than the postdoctoral offers available to me.
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With an effort to investigate possible relationship between flavonoids and health, an accurate estimation of flavonoid intake is valuable. We estimated dietary flavonoid intake and identified the major food sources. Subjects were ...
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With an effort to investigate possible relationship between flavonoids and health, an accurate estimation of flavonoid intake is valuable. We estimated dietary flavonoid intake and identified the major food sources. Subjects were healthy adults aged >= 19 y (n=11,474) who completed the 24-h dietary recall of the Korean National Health and Nutritional Examination Survey (2010-2012). The US Department of Agriculture and newly estimated or published values for typical Korean foods were combined into a Korean-targeted flavonoid database. The mean intake of total flavonoid was 107 +/- 1.47 mg/d, with a higher intake in women than in men after energy-adjustment. Quercetin, cyanidin, genistein, daidzein, epigallocatechin 3-gallate, epicatechin, hesperetin, and luteolin were identified as major flavonoid compounds. Across the age range studied, flavonols and flavones showed a reversed U-shape curve; flavan-3-ol and flavanones showed a decreasing pattern; and anthocyanidins and isoflavones showed an increasing pattern. Forty-five food items were identified as contributing >2% of at least one flavonoid compound's intake. Kimchi was the major food source of total flavonoids, followed by green tea, persimmons, and soybeans. Single food items accounting for more than 50% of the intake of a specific flavonoid included persimmons (cyanidin), green tea (epigallocatechin, epicatechin-3-gallate, and epigallocatechin 3-gallate), black tea (thearubigin), tangerines (hesperetin and naringenin), and onions (isorhamnetin). This study provides information on Korean flavonoid intake to enable international comparisons, along with insight into how the sources and intake of various flavonoids vary according to age and gender. This work should facilitate future investigations of the association between flavonoid intake and health.
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Dr. Jeffrey Kirsch has retired as executive director of the Reuben H. Fleet Science Center, San Diego, California, effective June 30, 2013. Kirsch, former chair of the Giant Screen Cinema Association (GSCA), is recognized as a pio...
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Dr. Jeffrey Kirsch has retired as executive director of the Reuben H. Fleet Science Center, San Diego, California, effective June 30, 2013. Kirsch, former chair of the Giant Screen Cinema Association (GSCA), is recognized as a pioneer and major contributor to the production and exhibition of IMAX? films in science museums, and he has changed the face of science education in San Diego.
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It is obvious that the management of operational risk for nuclear power plants (NPPs) is critical for their sustainability. In this regard, it should be stressed that the establishment of digital main control rooms (MCRs) in NPPs ...
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It is obvious that the management of operational risk for nuclear power plants (NPPs) is critical for their sustainability. In this regard, it should be stressed that the establishment of digital main control rooms (MCRs) in NPPs is gradually increasing these days, which are distinguished from analog MCRs equipped with conventional devices. Since the operational conditions of human operators working in digital MCRs are entirely different from those of analog MCRs, human reliability data should be clarified from the viewpoint of the raw data to be included in the related probabilistic safety assessment (PSA). In this study, two sets of human reliability data collected from both analog and digital MCRs were compared with respect to 21 basic task types that are observable during the performance of proceduralized tasks (e.g., emergency operating procedures). As a result, it seems that human error probabilities (HEPs) of the digital MCR are lower than those of the analog MCR overall. However, since certain digital MCR HEPs are higher for several particular task types, uncertainty in PSA could be enlarged if human reliability data secured from an analog MCR are directly used to conduct the PSA of a digital MCR. This paper is an extended version of the paper submitted to the ESREL 2020-PSAM15 conference.
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Specification of PM2.5 transmission characteristics is important for pollution control, policymaking and prediction. In this paper, we propose weights for motif instances, thereby to implement a weighted higher-order clustering al...
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Specification of PM2.5 transmission characteristics is important for pollution control, policymaking and prediction. In this paper, we propose weights for motif instances, thereby to implement a weighted higher-order clustering algorithm for a weighted, directed PM2.5 network in the Yangtze River Delta (YRD) of China. The weighted, directed network we create in this paper includes information on meteorological conditions of wind speed and wind direction, plus data on geographic distance and PM2.5 concentrations. We aim to reveal PM2.5 mobility between cities in the YRD. Major potential PM2.5 contributors and closely interacted clusters are identified in the network of 178 air quality stations in the YRD. To our knowledge, it is the first work to incorporate weight information into the higher-order network analysis to study PM2.5 transport. (C) 2018 Elsevier B.V. All rights reserved.
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Anticoagulation therapy is a mainstay of the treatment of thrombotic disorders; however, conventional anticoagulants trade antithrombotic benefits for bleeding risk. Factor (f) XI deficiency, known as hemophilia C, rarely causes s...
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Anticoagulation therapy is a mainstay of the treatment of thrombotic disorders; however, conventional anticoagulants trade antithrombotic benefits for bleeding risk. Factor (f) XI deficiency, known as hemophilia C, rarely causes spontaneous bleeding, suggesting that fXI plays a limited role in hemostasis. In contrast, individuals with congenital fXI deficiency display a reduced incidence of ischemic stroke and venous thromboembolism, indicating that fXI plays a role in thrombosis. For these reasons, there is intense interest in pursuing fXI/factor XIa (fXIa) as targets for achieving antithrombotic benefit with reduced bleeding risk. To obtain selective inhibitors of fXIa, we employed libraries of natural and unnatural amino acids to profile fXIa substrate preferences. We developed chemical tools for investigating fXIa activity, such as substrates, inhibitors, and activity-based probes (ABPs). Finally, we demonstrated that our ABP selectively labels fXIa in the human plasma, making this tool suitable for further studies on the role of fXIa in biological samples.
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??Anticoagulation therapy is a mainstay of the treatment of thrombotic disorders; however, conventional anticoagulants trade antithrombotic benefits for bleeding risk. Factor (f) XI deficiency, known as hemophilia C, rarely causes...
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??Anticoagulation therapy is a mainstay of the treatment of thrombotic disorders; however, conventional anticoagulants trade antithrombotic benefits for bleeding risk. Factor (f) XI deficiency, known as hemophilia C, rarely causes spontaneous bleeding, suggesting that fXI plays a limited role in hemostasis. In contrast, individuals with congenital fXI deficiency display a reduced incidence of ischemic stroke and venous thromboembolism, indicating that fXI plays a role in thrombosis. For these reasons, there is intense interest in pursuing fXI/factor XIa (fXIa) as targets for achieving antithrombotic benefit with reduced bleeding risk. To obtain selective inhibitors of fXIa, we employed libraries of natural and unnatural amino acids to profile fXIa substrate preferences. We developed chemical tools for investigating fXIa activity, such as substrates, inhibitors, and activity-based probes (ABPs). Finally, we demonstrated that our ABP selectively labels fXIa in the human plasma, making this tool suitable for further studies on the role of fXIa in biological samples.
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A homogeneous series of heterobimetallic complexes of [R-Fc(4-py)Ru(NH3)(5)](PF6)(2) (R = II, Et, Br, acetyl; Fc(4-py) = 4-ferrocenylpyridine) have been prepared and characterized. The mixed-valence species generated in situ using...
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A homogeneous series of heterobimetallic complexes of [R-Fc(4-py)Ru(NH3)(5)](PF6)(2) (R = II, Et, Br, acetyl; Fc(4-py) = 4-ferrocenylpyridine) have been prepared and characterized. The mixed-valence species generated in situ using ferrocenium hexafluorophosphate as the oxidant show class II behavior, and the oxidized sites are ruthenium centered. Delta E-1/2, E-1/2(Fe-III/Fe-II) - E-1/2(Ru-III/Ru-II), an upper limit for Delta G degrees that is an energetic difference between the donor and acceptor sites, changes sharply and linearly with Gutmann solvent donor number (DN) and Hammett substituent constants (sigma). The solvent-dependent and substituent-dependent intervalence transfer bands were found to vary almost exclusively with Delta E-1/2. The activation energy for the optical electron transfer versus Delta E-1/2 plot yields a common nuclear reorganization energy (lambda) of 0.74 +/- 0.04 eV for this series. The equation that allows one to incorporate the effect of both solvent donicity and substituents on optical electron transfer is E-op = lambda + Delta G degrees, where Delta G degrees = (Delta G degrees)(intrinsic) + (Delta G degrees)(solvent donicity) + (Delta G degrees)(substituent effect) (Delta G degrees)(intrinsic) with a numerical value of 0.083 +/- 0.045 eV was obtained from the intercept of the Delta E-1/2 of [H-Fc(4-py)Ru(NH3)(5)](2+,3+,4+) versus DN plot. (Delta G degrees)(solvent donicity) was obtained from the average slopes of the Delta E-1/2 of [H-Fc(4-py)Ru(NH3)(5)](2+,3+,4+) versus DN plot, and (Delta G degrees)(substituent effect) was Obtained from the average slopes of the corresponding Delta E-1/2 versus a plot. The empirical equation allows one to finely tune E-op of this series to E-op = 0.82 + 0.019(DN) + 0.44 sigma eV at 298 K, and the discrepancy between the calculated and experimental data is less than 6%. [References: 42]
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