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961.
To reduce energy consumption and carbon dioxide (CO2 ) emissions in housing construction, the energy-intensive processes and life-cycle stages should be identified and integrated. The environmental impact of vertically integrated factory-built homes (VIHs) constructed with increased material inputs in Japan's northern island of Hokkaido was assessed using life-cycle inventory (LCI) analysis methods. Manufacturing process energy and CO2 intensities of the homes were evaluated based on the material inputs. They were compared with those of a counterpart home hypothetically built using the vertically integrated construction methods, but in accordance with the specifications of a less material-intensive conventional home (CH) in Hokkaido today. Cumulative household energy consumption and CO2 emissions were evaluated and compared with those of the production stages. The annual household energy consumption was compared among a VIH, a CH, and an average home in Hokkaido. The energy intensity of the VIH was 3.9 GJ production energy per m2 of floor area, 59% higher than that of the CH. Net CO2 emissions during VIH manufacturing processes were 293 kg/m2 , after discounting the carbon fixation during tree growth. The cumulative use-phase household energy consumption and CO2 emissions of a VIH will exceed energy consumption and CO2 emissions during the initial production stage in less than six years. Although VIHs housed 21% more residents on average, the energy consumption per m2 was 17% lower than that of a CH. This may indicate that using more materials initially can lead to better energy efficiency. 相似文献
962.
A novel superfamily of guanine nucleotide exchange factors for Rho GTPases includes DOCK180 and zizimin1. The zizimin subfamily includes three genes of which only zizimin1 has been cloned. We report here the cloning of zizimin2, identified in a screen for genes enriched in germinal center B cells. Zizimin2 and zizimin1 have similar primary structures and both proteins bound and activated Cdc42 but not the Cdc42-related proteins TC10 or TCL. Their tissue distributions are distinct, however, with zizimin2 expressed predominantly in lymphocytes and an opposite pattern for zizimin1. Zizimin3 was also analyzed and showed distinct GTPase specificity and tissue distribution. 相似文献
963.
Isu are scaffold proteins involved in iron-sulfur cluster biogenesis and playing a key role in yeast mitochondria and Escherichia coli. In this work, we have characterized the Arabidopsis thaliana Isu gene family. AtIsu1,2,3 genes encode polypeptides closely related to their bacterial and eukaryotic counterparts. AtIsu expression in a Saccharomyces cerevisiae Deltaisu1Deltanfu1 thermosensitive mutant led to the growth restoration of this strain at 37 degrees C. Using Isu-GFP fusions expressed in leaf protoplasts and immunodetection in organelle extracts, we have shown that Arabidopsis Isu proteins are located only into mitochondria, supporting the existence of an Isu-independent Fe-S assembly machinery in plant plastids. 相似文献
964.
Yue Feng Sewon Kim Sang Yeol Lee Hisashi Koiwa 《Biochemical and biophysical research communications》2010,397(2):355-360
RNA polymerase II carboxyl-terminal domain (pol II CTD) phosphatases that can dephosphorylate both Ser2-PO4 and Ser5-PO4 of CTD have been identified in animals and yeasts, however, only Ser5-PO4-specific CTD phosphatases have been identified in plants. Among predicted Arabidopsis SCP1-like small phosphatases (SSP), SSP4, SSP4b, and SSP5 form a unique group with long N-terminal extensions. While SSPs’ expression showed similar tissue-specificities, SSP4 and SSP4b were localized exclusively in the nuclei, whereas SSP5 accumulated in both nuclei and cytoplasm. Detailed characterization of SSP activities using various peptides and full-length Arabidopsis pol II CTD substrates established that SSP4 and SSP4b could dephosphorylate both Ser2-PO4 and Ser5-PO4 of CTD, whereas SSP5 dephosphorylated only Ser5-PO4. These results indicate that Arabidopsis SSP gene family encodes active CTD phosphatases like animal SCP1 family proteins, with distinct substrate specificities. 相似文献
965.
Joanne L. Mansell Elliott R. Jacobson Jack M. Gaskin 《In vitro cellular & developmental biology. Plant》1989,25(11):1062-1064
Summary Two fibroblastic cell lines were established from explants of fibropapillomas of each of two different green turtles (Chelonia mydas). These cells, designated GTFP (Green Turtle Fibropapilloma), were subcultured approximately 30 times at 30°C in Eagle’s
minimal essential media supplemented with 2 to 10% fetal bovine serum. The ultrastructural morphology of the cultured fibroblasts
is described. The cells contained abundant rough endoplasmic reticulum, polyribosomes, and mitochondria; collagen fibrils
were visible in the extracellular space. No viruslike particles or evidence of other pathogenic agents could be demonstrated
by electron microscopy in any of the cultured cells examined.
Supported in part by a grant from Sea World Research Institute, Hubbs Marine Research Center, San Diego, California 92109,
and the Chelonia Institute, Arlington, Virginia 22209. Published as University of Florida, College of Veterinary Medicine,
Journal Series no. 192. 相似文献
966.
It has been suggested that syntaxin 5 (Syx5) participates in vesicular transport. We examined the effects of Syx5 down-regulation on the morphology of the Golgi apparatus and the transport of vesicles in mammalian cells. Knockdown of the Syx5 gene resulted in Golgi fragmentation without changing the level of endoplasmic reticulum (ER)-resident proteins, other Golgi-SNAREs (soluble N-ethylmaleimide-sensitive factor-attachment protein receptors), and coatmer proteins. Strikingly, a major decrease in Syx5 expression barely affected the anterograde transport of vesicular stomatitis virus G (VSVG) protein to the plasma membrane. These results suggest that Syx5 is required for the maintenance of the Golgi structures but may not play a major role in the transport of vesicles carrying VSVG between the ER and the Golgi compartment. 相似文献
967.
In many countries, the algae of “green tides” are harvested in the fight against pollution. Ulva often represents the main component of the tide, and intensive research has been conducted on the possibility to use the algae as a methanisation substrate. However, methanisation is hampered by various practical obstacles, which requires a compromise between productivity and biological yield.The process described here calls upon a pre-digestion phase of Ulva which, besides the economy of time and volume of the digestion, makes it possible to obtain a biogas of good quality. The methanisation substrate is the hydrolysis juice collected by draining, followed by pressing. The cake resulting from the pressing process can be used as organic enriching or fertilizing agent in agriculture. Various presses were tested. The screw press was found the most suitable to recover a great quantity of sufficiently loaded pressing juice after only a short hydrolysis time. For a 3 month hydrolysis period, the different fractions amounted to 158 L of hydrolysis juice, 192 L of pressing juice, and 0.075 m3 of cake per m3 of initial algae.The bi-phasic anaerobic digestion with forced recuperation of juices offers interesting pollution abatement perspectives, with total and soluble chemical oxygen demand cleaning rates of respectively 79 and 95% during the methanogenic phase, for a volume productivity of 1.5 m3 CH4 m−3digester day−1. The quality of the Ulva juice also makes it suitable for use as substrate for industrial processes or co-substrate of methanisation in pre-existing reactors, so that subsequent investment could be avoided. 相似文献
968.
Objective: To determine the prevalence of oral mucosal lesions, temporomandibular joint (TMJ) impairment and oral health‐related habits in the elderly people in South East Local Government Area (SELGA) in Ibadan. Background data: SELGA is one of the largest local government areas in Oyo State, Nigeria and has a population of 225 800. Design: A cross‐sectional survey. Methodology: A randomly selected sample of 690 elderly people from 23 wards in SELGA were examined by two trained and calibrated examiners using mirror, probe and natural light. Results: One hundred and fifty‐five (22.46%) of the elderly examined had one or more oral pathology lesions, representing infection‐related swelling, non‐infection‐related swelling, pre‐malignant lesions, denture stomatitis, non‐denture based ulcers, angular cheilitis, geographic tongue, scrotal tongue, lichen planus, hyper‐pigmentation and TMJ impairment. Fifty‐five (35.5%) of these pathologies were infection‐related swellings. Six (3.9%) of the pathologies were denture‐related stomatitis, 14(9.03%) were pre‐malignant lesions, 14(9.03%) were non‐infection‐related swelling, while 27 (17.4%) were TMJ impairment. The rest of the lesions constituted the remaining 25.1%. Only 15.9% of the participants had tobacco‐related habits, 10.7% drank alcohol, whilst 41.6% chewed kola nuts. Conclusion: Oral pathoses prevalence (22.46%) was similar to findings in developed countries (29.9%) but with a reversal of causal factors, infection‐related swellings were more common, whereas pre‐malignant lesions were less common. The infections were mostly complications from periodontal disease, which culminated in abscess formation. Tobacco‐related habits were not highly prevalent among the elderly people in SELGA. However, oral pathoses resulting from nutritional deficiencies were the third most frequent lesions observed. 相似文献
969.
茶蚜对不同SPAD值绿色的趋性 总被引:1,自引:0,他引:1
以茶蚜(Toxoptera aurantii)为研究对象,研究其对模拟SPAD值(叶色值)绿色和不同施氮量处理茶梢的趋性。结果表明:不同虫态茶蚜对不同SPAD值绿色的趋性存在显著差异,茶树叶片含氮量与其SPAD值之间存在显著的线性关系,茶蚜各虫态对模拟绿色趋性最强的SPAD值的相应含氮量分别为:低龄若蚜在2.83%左右,高龄若蚜在2.83%~3.14%,有翅和无翅成虫在3.14%左右;而各虫态表现出最大趋性的茶树叶片相应含氮量分别为:低龄若蚜在2.64%~3.13%,高龄若蚜在2.68%~2.83%,无翅成虫在2.42%~2.84%,有翅成虫在2.63%~3.13%。表明不同虫态茶蚜对茶树叶片含氮量的需要存在差异,其结果可为茶园合理施肥以及控制蚜虫危害提供依据。 相似文献
970.
Benjamin T. Andrews 《Journal of molecular biology》2009,392(1):218-2578
Green fluorescent protein (GFP) possesses a unique folding landscape with a dual basin leading to the hysteretic folding behavior observed in experiment. While theoretical data do not have the resolution necessary to observe details of the chromophore during refolding, experimental results point to the chromophore as the cause of the observed hysteresis. With the use of NMR spectroscopy, which probes at the level of the individual residue, the hysteretic intermediate state is further characterized in the context of the loosely folded isomerized native-like state {Niso} predicted in simulation. In the present study, several residues located in the lid of GFP indicate heterogeneity of the native states. Some of these residues show chemical shifts when the native-like intermediate {Niso} responsible for GFP's hysteretic folding behavior is trapped. Observed changes in the chromophore are consistent with increased flexibility or isomerization in {Niso} as predicted in recent theoretical work. Here, we observed that multiple chromophore environments within the native state are averaged in the trapped intermediate, linking chromophore flexibility to mispacking in the trapped intermediate. The present work is experimental evidence for the proposed final “locking” mechanism in GFP folding forming an incorrectly or loosely packed barrel under intermediate (hysteretic) folding conditions. 相似文献