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61.
A new functional porous carbons (PC-WF) is prepared by activation-pyrolysis method use waste cotton fabrics (WF) as an abundant, cheap and available precursor for removal of Brilliant Crocein (BC-GR) and Cationic Red 2GL (CR-GL) from aqueous phase. The PC-WF was characterized by BET, FTIR, SEM, and XRD techniques, the surface area, total pore volume, average pore diameter was found as 1463.5 m2 g-1, 0.783 cm3 g-1 and 2.14 nm, respectively. The influences on BC-GR and CR-GL adsorption of various experimental factors such as initial concentration and temperature were investigated. Adsorption kinetics was found to be best represented by the pseudo-second order model. The adsorption capacity was 319.8 mg g-1 for BC-GR and 842.5 mg g-1 for CR-GL at 30 °C, respectively. The results indicate that for waste cotton fabrics in particular, the practical application of this process to the production of porous carbon would be possible.  相似文献   
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To express CTB-IsdBid-Clfais(CIC) protein and evaluate its immunogenicity, CTB (as a molecular adjuvant) could be tandem linked with IsdBid-Clfais gene by the overlapping PCR method, then CTB-IsdBid-Clfais(CIC) was inserted into pET-32a(+) vector to construct recombinant plasmids pET-32a(+)-CTB-IsdBid-Clfais. The recombinant plasmids pET-32a(+)-CTB-IsdBid-Clfais were transformed into Escherichia coli (E.coli) BL21 to express the CTB-IsdBid-Clfa(CIC) protein, the CIC expression protein and its immune activity were detected by Western blotting and ELISA,respectively. The results showed that the length of CIC gene were 2 072 bp, and CIC was correctly inserted into the pET-32a(+) plasmids, the pET-32a(+)-CTB-IsdBid-Clfais recombinant plasmids were successfully constructed. Western blotting result confirmed that the molecular weight of CIC proteins was 95.9 ku, which were correctly expressed by E.coli BL21 with pET-32a (+)-CTB-IsdBid-Clfais plasmids. ELISA results showed that there was no significant difference among the CIC, IsdBid and Clfais protein groups (P>0.05), and there was extremely significant difference between CIC and BSA protein groups (P<0.01). In conclusion, the pET-32a(+)-CTB-IsdBid-Clfais recombinant plasmids were successfully constructed, CIC proteins were correctly expressed, and were able to react with serum from mice immunized with IsdBid and Clfais,respectively,therefore, CIC proteins had strong immune activity.  相似文献   
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Forest losses or gains have long been recognized as critical processes modulating the carbon flux between the biosphere and the atmosphere. Timely, accurate and spatially explicit information on forest disturbance and recovery history is required for assessing the effectiveness of existing forest management. The major objectives of our research focused on testing the mapping efficacy of the vegetation change tracker (VCT) model over a forested area in China. We used a new version of VCT algorithm built upon the Landsat time series stacks (LTSS). The LTSS consisted of yearly image acquisitions to map forest disturbance history from 1987 to 2011 over the Ning-Zhen Mountains, Jiangsu Province of east China. The LTSS consisted of TM and ETM+ scenes with different projections due to distinct data sources (Beijing remote sensing ground station and the USGS EROS Center). The validation results of the disturbance year maps showed that most spatial agreement measures ranged from 70 to 86 %, comparable with the VCT accuracies reported for many places in USA. Very low accuracies were identified in 1995 (38.3 %) and 1992 (56.2 %) in the current analysis. These resulted from the insensitivity of the VCT algorithm to detect low intensity disturbances and also from the mis-registration errors of the image pairs. Major forest disturbance types existing in our study area were identified as agricultural expansion (39.8 %), urbanization (24.9 %), forest management practice (19.3 %), and mining (12.8 %). In general, there was a gradual decreasing trend in forest cover throughout this region, caused principally by China’s economic, demographic, environmental and political policies and decisions, as well as some weather events. While VCT has largely been used to assess long term changes and trends in the USA, it has great potential for assessing landscape level change elsewhere throughout the world.  相似文献   
67.
The effects of ammonia and nitrite on vigour, survival rate, moulting rate of zoea of blue swimming crab, Portunus pelagicus, were studied. A total of five nitrite-N treatments (26.67, 53.34, 106.68, 213.36, 426.72 mg/l) and a control (no nitrite-N added) were set up for the acute nitrite-N toxicity experiment; a total of five ammonia-N treatments (8.43, 16.86, 33.72, 67.44, 134.88 mg/l) and a control (no ammonia-N added) were set up for the acute ammonia-N toxicity experiment. The results showed that the vigour, survival rate and moulting rate of zoea of the blue swimming crabs exposed to over 53.34 mg/l were significantly different (P < 0.05) from the control group. The zoea LC50 values (mg/l) of nitrite-N were 179.47, 76.56, 66.70, 37.49, 25.01, 25.35, 25.34 mg/l for 24, 36, 48, 60, 72, 84, 96 h, respectively. The vigour, survival rate and moulting rate of zoea of the blue swimming crabs exposed to over 16.86 mg/l were significantly different (P < 0.05) from the control group. The zoea LC50 values (mg/l) of ammonia-N were 51.04, 39.62, 38.72, 24.43, 16.90, 13.42, 11.16 mg/l for 24, 36, 48, 60, 72, 84, 96 h, respectively. The zoeae are highly sensitive to ammonia and nitrite, and the toxicity of ammonia and nitrite on Portunus pelagicus decrease with development of this crab.  相似文献   
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In the dairy cow, negative energy balance affects milk yield and composition as well as animal health. Studying the effects of negative energy balance on dairy cow milk production is thus essential. Feed restriction (FR) experiments attempting to reproduce negative energy balance by reducing the quantity or quality of the diet were conducted in order to better describe the animal physiology changes. The study of FR is also of interest since with climate change issues, cows may be increasingly faced with periods of drought leading to a shortage of forages. The aim of this article is to review the effects of FR during lactation in dairy cows to obtain a better understanding of metabolism changes and how it affects mammary gland activity and milk production and composition. A total of 41 papers studying FR in lactating cows were used to investigate physiological changes induced by these protocols. FR protocols affect the entire animal metabolism as indicated by changes in blood metabolites such as a decrease in glucose concentration and an increase in non-esterified fatty acid or β-hydroxybutyrate concentrations; hormonal regulations such as a decrease in insulin and insulin-like growth factor I or an increase in growth hormone concentrations. These variations indicated a mobilization of body reserve in most studies. FR also affects mammary gland activity through changes in gene expression and could affect mammary cell turnover through cell apoptosis, cell proliferation, and exfoliation of mammary epithelial cells into milk. Because of modifications of the mammary gland and general metabolism, FR decreases milk production and can affect milk composition with decreased lactose and protein concentrations and increased fat concentration. These effects, however, can vary widely depending on the type of restriction, its duration and intensity, or the stage of lactation in which it takes place. Finally, to avoid yield loss and metabolic disorders, it is important to identify reliable biomarkers to monitor energy balance.  相似文献   
70.
旨在探究产蛋各期番鸭肝腺苷酸活化蛋白激酶(AMPK)信号通路基因表达和肝脂肪酸组成,为番鸭肝脂质代谢应答产蛋提供机理研究。本研究选取开产前22周龄、产蛋初期30周龄、产蛋中期40周龄和产蛋末期60周龄母番鸭各15羽,全自动生化仪测定血脂水平,苏木精-伊红(HE)染色和油红O染色观察肝组织学结构,实时荧光定量PCR (qRT-PCR)检测肝AMPK通路基因表达,气相色谱-质谱联用法(GC-MS)检测产蛋各期肝脂肪酸组成。结果表明,总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、甘油三酯(TG)和极低密度脂蛋白胆固醇(VLDL-C)水平在40周龄显著高于22、30和60周龄(P<0.05);高密度脂蛋白胆固醇(HDL-C)水平在30和40周龄显著低于22和60周龄(P<0.05)。肝HE和油红O染色切片显示,肝在22周龄呈实质状,至产蛋40和60周龄,肝脂滴沉积明显(P<0.05)。AMPKα1在22、30、40和60周龄呈本底低水平表达,并显著低于产蛋各期肉碱脂酰转移酶1(CPT1)和脂肪酸合成酶(FAS)的表达量(P<0.05),FAS在22、40和60周龄均呈高水平表达(P<0.05);羟甲基戊二酰辅酶A还原酶(HMGR)、肝细胞核因子4αHNF4α)、乙酰辅酶A羧化酶1(ACC1)和固醇调控元件结合蛋白-1(SREBP1c)在40周龄表达量显著高于22和30周龄(P<0.05)。肝中饱和脂肪酸(SFA)、单不饱和脂肪酸(MUFA)和多不饱和脂肪酸(PUFA)主要由C16∶0、C18∶0、C18∶1和C20∶2 n-6构成,分别占总脂肪酸含量的32%、16%、30%和9%。C14∶0和C16∶0含量在40周龄显著高于22周龄(P<0.05);C24∶0、C20∶2 n-6和PUFA含量在60周龄显著高于22和40周龄(P<0.05)。综上,番鸭产蛋期肝通过上调FAS等脂质合成基因表达,合成大量长链脂肪酸,沉积于肝,并增加血脂水平。  相似文献   
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