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31.
Jyotirmay Mathur Narendra Kumar Bansal 《The International Journal of Life Cycle Assessment》1999,4(2):113-116
This analysis can be called energy accounting of solar water heating systems. Five types of solar water heating systems have
been considered. With the help of material balance, energy content has been found in these systems. Yearly output of systems
has been found by conducting transient simulations using hourly data of radiation and ambient temperature. Such analysis has
been done separately for one representative city of each of six climatic zones of India. The energy payback for India ranges
from 0.73 to 4.16 years for the thirty cases considered here. 相似文献
32.
Turcotte LP Swenberger JR Tucker MZ Yee AJ Trump G Luiken JJ Bonen A 《Molecular and cellular biochemistry》2000,210(1-2):53-63
Studies show that uptake of long-chain fatty acids (LCFA) across the plasma membranes (PM) may occur partly via a carrier-mediated process and that the plasma membrane fatty acid-binding protein (FABPPM) may be a component of this system. To test the hypothesis that FABPPM is involved in transsarcolemmal transport of LCFA in muscle, we measured palmitate uptake in giant sarcolemmal vesicles and palmitate binding to PM proteins in rat muscles, (1) in the presence of increasing amounts of unbound palmitate and (2) in the absence or presence of antibody to FABPPM. Both palmitate uptake and binding were found to be saturable functions of the unbound palmitate concentration with calculated Vmax values of 10.5 ± 1.2 pmol/mg protein/15 sec and 45.6 ± 2.9 nmol/mg protein/15 min and Km values of 12.8 ± 3.8 and 18.4 ± 1.8 nmol/L, respectively. The Vmax values for both palmitate uptake and binding were significantly decreased by 75-79% in the presence of a polyclonal antibody to the rat hepatic FABPPM. Antibody inhibition was found to be dose-dependent and specific to LCFA. Glucose uptake was not affected by the presence of the antibody to FABPPM. Palmitate uptake and binding were also inhibited in the presence of trypsin and phloretin. These results support the hypothesis that transsarcolemmal LCFA transport occurs in part by a carrier-mediated process and that FABPPM is a component of this process in muscle. 相似文献
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The coastal mosquito Aedes togoi occurs more or less continuously from subarctic to subtropic zones along the coasts of the Japanese islands and the East Asian mainland. It occurs also in tropical Southeast Asia and the North American Pacific coast, and the populations there are thought to have been introduced from Japan by ship. To test this hypothesis, the genetic divergence among geographic populations of A. togoi was studied using one mitochondrial and three nuclear gene sequences. We detected 71 mitochondrial haplotypes forming four lineages, with high nucleotide diversity around temperate Japan and declining towards peripheral ranges. The major lineage (L1) comprised 57 haplotypes from temperate and subarctic zones in Japan and Southeast Asia including southern China and Taiwan. Two other lineages were found from subtropical islands (L3) and a subarctic area (L4) of Japan. The Canadian population showed one unique haplotype (L2) diverged from the other lineages. In the combined nuclear gene tree, individuals with mitochondrial L4 haplotypes diverged from those with the other mitochondrial haplotypes L1—L3; although individuals with L1—L3 haplotypes showed shallow divergences in the nuclear gene sequences, individuals from Southeast Asia and Canada each formed a monophyletic group. Overall, the genetic composition of the Southeast Asian populations was closely related to that of temperate Japanese populations, suggesting recent gene flow between these regions. The Canadian population might have originated from anthropogenic introduction from somewhere in Asia, but the possibility that it could have spread across the Beringian land bridge cannot be ruled out. 相似文献
35.
Lu SC Atangan L Won Kim K Chen MM Komorowski R Chu C Han J Hu S Gu W Véniant M Wang M 《Journal of lipid research》2012,53(4):643-652
The aim of this study is to investigate the capability of an apoA-I mimetic with multiple amphipathic helices to form HDL-like particles in vitro and in vivo. To generate multivalent helices and to track the peptide mimetic, we have constructed a peptibody by fusing two tandem repeats of 4F peptide to the C terminus of a murine IgG Fc fragment. The resultant peptidbody, mFc-2X4F, dose-dependently promoted cholesterol efflux in vitro, and the efflux potency was superior to monomeric 4F peptide. Like apoA-I, mFc-2X4F stabilized ABCA1 in J774A.1 and THP1 cells. The peptibody formed larger HDL particles when incubated with cultured cells compared with those by apoA-I. Interestingly, when administered to mice, mFc-2X4F increased both pre-β and α-1 HDL subfractions. The lipid-bound mFc-2X4F was mostly in the α-1 migrating subfraction. Most importantly, mFc-2X4F and apoA-I were found to coexist in the same HDL particles formed in vivo. These data suggest that the apoA-I mimetic peptibody is capable of mimicking apoA-I to generate HDL particles. The peptibody and apoA-I may work cooperatively to generate larger HDL particles in vivo, either at the cholesterol efflux stage and/or via fusion of HDL particles that were generated by the peptibody and apoA-I individually. 相似文献
36.
Martin L. Decaris Claire L. Emson Kelvin Li Michelle Gatmaitan Flora Luo Jerome Cattin Corelle Nakamura William E. Holmes Thomas E. Angel Marion G. Peters Scott M. Turner Marc K. Hellerstein 《PloS one》2015,10(4)
Accumulation and degradation of scar tissue in fibrotic liver disease occur slowly, typically over many years. Direct measurement of fibrogenesis, the rate of scar tissue deposition, may provide valuable therapeutic and prognostic information. We describe here results from a pilot study utilizing in vivo metabolic labeling to measure the turnover rate of hepatic collagen and collagen-associated proteins in plasma for the first time in human subjects. Eight subjects with chronic liver disease were labeled with daily oral doses of 2H2O for up to 8 weeks prior to diagnostic liver biopsy and plasma collection. Tandem mass spectrometry was used to measure the abundance and fractional synthesis rate (FSR) of proteins in liver and blood. Relative protein abundance and FSR data in liver revealed marked differences among subjects. FSRs of hepatic type I and III collagen ranged from 0.2–0.6% per day (half-lives of 4 months to a year) and correlated significantly with worsening histologic fibrosis. Analysis of plasma protein turnover revealed two collagen-associated proteins, lumican and transforming growth factor beta-induced-protein (TGFBI), exhibiting FSRs that correlated significantly with FSRs of hepatic collagen. In summary, this is the first direct measurement of liver collagen turnover in vivo in humans and suggests a high rate of collagen remodeling in advanced fibrosis. In addition, the FSRs of collagen-associated proteins in plasma are measurable and may provide a novel strategy for monitoring hepatic fibrogenesis rates. 相似文献
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39.
Christina M. Giovas Michelle J. LeFebvre Scott M. Fitzpatrick 《Journal of Biogeography》2012,39(3):476-487
Aim This paper investigates the prehistoric introduction of five mammalian taxa to Carriacou (Lesser Antilles) and refines the known anthropogenic ranges for these fauna in the pre‐Columbian West Indies. The importance of such records for understanding the region’s historical biogeography and ecology is considered. Location Carriacou Island, Grenada (12°28′ N, 61°26′ W). Methods Zooarchaeological assemblages from Carriacou’s earliest documented prehistoric sites, Grand Bay and Sabazan, were analysed, and exotic taxa were identified and quantified. The timing of introductions was established based on multiple radiocarbon assays, including three new accelerator mass spectrometry (AMS) direct dates obtained on the bone of exotic taxa. Source species and location(s) are considered and compared with known prehistoric records for the Caribbean to synthesize anthropogenic distributions for the pre‐Columbian period. The contexts of the zooarchaeological remains are evaluated to better understand the nature and purpose of introductions. Results Zooarchaeological investigation on Carriacou reveals the occurrence of multiple mammal introductions from South American between c. ad 700 and ad 1400. This paper presents the first records for guinea pig (Cavia sp.), armadillo (Dasypus sp.), peccary (Tayassu/Pecari sp.), opossum (Didelphis sp.) and agouti (Dasyprocta sp.) from the island. Human‐mediated transport of these taxa is indicated by their absence from the record prior to human settlement of Carriacou. Several translocated species are either rare or entirely unknown for the region, and overall West Indian distributions are temporally and spatially discontinuous. Archaeological contexts indicate that mammalian introductions arose from human subsistence needs, but other social factors may have shaped the dispersal of these fauna. Main conclusions The taxonomic combination and richness of Carriacou’s introduced fauna are unusual within the region. Importantly, the new records significantly improve the known pre‐Columbian geographic range for peccary, guinea pig and armadillo. Integrated with regional records, these data augment our understanding of the Caribbean’s historical biogeography, and have the potential to improve our understanding of human mobility and anthropogenic environmental impacts in the West Indies prior to the arrival of Europeans. 相似文献
40.
Mark S. Tichenor John M. Keith William M. Jones Joan M. Pierce Jeff Merit Natalie Hawryluk Mark Seierstad James A. Palmer Michael Webb Mark J. Karbarz Sandy J. Wilson Michelle L. Wennerholm Filip Woestenborghs Dominiek Beerens Lin Luo Sean M. Brown Marlies De Boeck Sandra R. Chaplan J. Guy Breitenbucher 《Bioorganic & medicinal chemistry letters》2012,22(24):7357-7362
The structure–activity relationships for a series of heteroaryl urea inhibitors of fatty acid amide hydrolase (FAAH) are described. Members of this class of inhibitors have been shown to inactivate FAAH by covalent modification of an active site serine with subsequent release of an aromatic amine from the urea electrophile. Systematic Ames II testing guided the optimization of urea substituents by defining the structure–mutagenicity relationships for the released aromatic amine metabolites. Potent FAAH inhibitors were identified having heteroaryl amine leaving groups that were non-mutagenic in the Ames II assay. 相似文献