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81.
Environmental management, being an important component in strategies for achieving sustainable development of processes and products, has emerged as a proactive approach in majority of the manufacturing organizations. From the strategic perspective environmentally conscious manufacturing (ECM) programs lead to better environmental management practice. The objective of the current paper is to present an integrated and holistic framework to evaluate ECM programs. This framework combines three multi-criteria decision analysis (MCDA) methods to consider eight major environmentally conscious manufacturing indicators (ECMI) in order to identify the efficiency of each ECM program. First the interdependence relationship among the ECMIs is established using decision-making trail and evaluation laboratory (DEMATEL). Then a range of weightage (i.e. upper and lower bounds) is created for each ECMI using analytic network process (ANP) to include managerial preferences. Finally, this range of weightage for each indicator is applied to perform restricted multiplier data envelopment analysis (RMDEA). Results show that the technical efficiency of the inefficient ECM programs for integrated RMDEA, on average, is calculated as 53.2% whereas traditional input oriented DEA provides the same score as 72.3%. This clearly indicates that integrated RMDEA is better than the input oriented DEA because same level of output could be produced with lesser resources if the ECM programs perform on the frontier. Hence, the advantage of this methodology is that the managerial preferences are successfully implemented through this newly developed hybrid methodology that will help to reduce less resource consumption and lead to better environmental policy.  相似文献   
82.
《Cytokine》2015,74(2):245-252
BackgroundWe aimed to investigate the use of novel serum biomarkers for predicting the recurrence and survival of patients with hepatitis B virus (HBV)-related early hepatocellular carcinoma (HCC) after hepatic resection or radiofrequency ablation (RFA).MethodsOne hundred and five patients with HBV-related HCC, who fulfilled the Milan criteria without vascular invasion and underwent hepatic resection or RFA, were followed-up for a median duration of 52 months. Pretreatment serum concentrations of 16 cytokines including interleukin-6 (IL-6) were measured by using a Luminex 200 system. The measured serum cytokines and several clinical factors were analyzed retrospectively.ResultsUnivariate analysis showed that patients with lower pretreatment serum levels of IL-10, IL-6, monocyte chemoattractant protein-1, and tumor necrosis factor-α had significantly shorter disease-free survival (DFS) than those with higher levels. Multivariate analysis revealed that a low serum IL-6 level (⩽33.00 pg/mL; hazard ratio [HR] = 5.39; 95% confidence interval [CI] = 1.27–22.93; P = 0.022), low platelet count (<100 × 109/L; HR = 2.23; 95% CI = 1.28–3.89; P = 0.005), and low serum albumin level (⩽3.5 g/L; HR = 2.26; 95% CI = 1.28–3.97; P = 0.005) had a negative prognostic impact on DFS. In the analysis for overall survival, a low serum platelet level (<100 × 109/L; HR = 2.80; 95% CI = 1.31–5.99; P = 0.008) and multiple tumor (⩾2; HR = 4.05; 95% CI = 1.56–10.48; P = 0.004) showed a negative prognostic impact on the overall survival.ConclusionA low serum IL-6 level is, in addition to low platelet count and low serum albumin level, an independent prognostic factor for DFS in patients with HBV-related early HCC who underwent hepatic resection or RFA with curative intention.  相似文献   
83.
The growing demand of human populations for food supplies has led to an increase in the use of synthetic products, mainly pesticides, which induce adverse effects not only to target organisms, but also to non-target biota of agroecosystems. Aquatic ecosystems in the proximity of agricultural areas are particularly vulnerable to pesticides, which cause underperformance or extinction of non-target sensitive species. Once in the aquatic system, these chemicals can affect biological processes at multiple levels (molecular, individual, populational), causing ecosystem imbalance across multiple scales. In this study, the effect of a commercial formulation of a herbicide (Primextra® Gold TZ) and its main active ingredient (a.i., S-metolachlor) was studied on a freshwater cladoceran species (Daphnia longispina), at different levels of biological organization and temporal scales. S-metolachlor is used in many herbicide formulations applied in corn/maize cultures, which is a relevant culture worldwide. As a first step, the acute and chronic effects of both commercial formulation and a.i. were quantified, and both formulations negatively affected the cladoceran's survival and reproductive parameters (age at first reproduction, number of offspring and number of broods), as well as the population's rate of increase. Whilst acute effects were comparable, the commercial formulation was slightly more toxic (EC50 was two-times lower) than the a.i. in chronic exposures, being prejudicial to D. longispina populations above 4.0 mg/L of S-metolachlor. In a second experimental step, we focused on the potential multi-generational impacts of the exposure to the a.i. alone on biochemical (lipid biomarkers, namely fatty acids) and populational responses, because of the relevance of S-metolachlor as a biosynthesis inhibitor in many herbicidal formulations. The herbicide caused a significant decrease in Daphnia fecundity (in the size of the 1st clutch), but no concomitant alterations were found in fatty acid profiles of mothers or offspring. More important, this experiment showed that S-metolachlor did not cause effects in the subsequent generation, thus suggesting that biotic communities may recover after exposure to the xenobiotic.  相似文献   
84.
Degeneration of mesencephalic dopaminergic (mesDA) neurons is the pathological hallmark of Parkinson’s diseae. Study of the biological processes involved in physiological functions and vulnerability and death of these neurons is imparative to understanding the underlying causes and unraveling the cure for this common neurodegenerative disorder. Primary cultures of mesDA neurons provide a tool for investigation of the molecular, biochemical and electrophysiological properties, in order to understand the development, long-term survival and degeneration of these neurons during the course of disease. Here we present a detailed method for the isolation, culturing and maintenance of midbrain dopaminergic neurons from E12.5 mouse (or E14.5 rat) embryos. Optimized cell culture conditions in this protocol result in presence of axonal and dendritic projections, synaptic connections and other neuronal morphological properties, which make the cultures suitable for study of the physiological, cell biological and molecular characteristics of this neuronal population.  相似文献   
85.
The involvement of gibberellins in the control of flowering of sunflower was studied by direct application of GA3 to the apex of the plants, analysis of the endogenous levels of gibberellin-like substances at different plant ages, and indirectly by the application of paclobutrazol, an inhibitor of gibberellin synthesis. GA3 speeded-up flower initiation and floral apex development. The time of GA3 application was more critical than the amount of GA3 applied. The endogenous levels of gibberellin-like compounds increased significantly by day 15 after sowing. The application of paclobutrazol markedly delayed floral initiation and this effect was also depedent on plant age. Both GA3 and paclobutrazol had their greatest effects between 10 and 20 days after sowing suggesting that an increase in gibberellins in that time period plays a role in floral initiation.  相似文献   
86.
Effects of drought on nutrient and ABA transport in Ricinus communis   总被引:1,自引:1,他引:0  
We studied the effects of variations of water flux through the plant, of diurnal variation of water flux, and of variation of vapour pressure deficit at the leaf on compensation pressure in the Passioura-type pressure chamber, the composition of the xylem sap and leaf conductance in Ricinus communis. The diurnal pattern of compensation pressure showed stress relaxation during the night hours, while stress increased during the day, when water limitation increased. Thus compensation pressure was a good measure of the momentary water status of the root throughout the day and during drought. The bulk soil water content at which predawn compensation pressure and abscisic acid concentration in the xylem sap increased and leaf conductance decreased, was high when the water usage of the plant was high. For all xylem sap constituents analysed, variations in concentrations during the day were larger than changes in mean concentrations with drought. Mean concentrations of phosphate and the pH of the xylem sap declined with drought, while nitrate concentration remained constant. When the measurement leaf was exposed to a different VPD from the rest of the plant, leaf conductance declined by 400mmol m?2 s?1 when compensation pressure increased by 1 MPa in all treatments. The compensation pressure needed to keep the shoot turgid, leaf conductance and the abscisic acid concentration in the xylem were linearly related. This was also the case when the highly dynamic development of stress was taken into account.  相似文献   
87.
A synthetic polynucleotide (TG)n was hybridized to equine DNA digested with HinfI and hypervariable hybridization patterns were obtained. Mendelian inheritance of these DNA fingerprinting patterns was confirmed by pedigree analysis. Estimates of the probabilities of identical band patterns in unrelated individuals of different breeds (Swedish Trotters, North Swedish Trotters, Thoroughbreds and Arabians) were in the range 1 times 10-4-7 times 10-6 The variability derived with the (TG)n, probe in horses was higher than what we obtained with several other commmonly used probes for DNA fingerprinting. Individuals within breeds tended to be more similar to each other with regard to DNA fingerprint pattern than to individuals of other breeds. Moreover, a parsimony analysis made on the basis of the hybridization patterns gave clustering of individuals within breeds. The possibility of using hypervariable probes for the identification of breed-specific characters is discussed.  相似文献   
88.
In central Italy, Prunus cerasus var. austera is cultivated as small stands or scattered trees in marginal areas for the production of jam and wine. Thanks to the healthy attributes of its products and its ability to grow in different environmental conditions, this variety has gained new interest in the development of marginal areas. We assessed the level of the genetic variability of P. cerasus var. austera germplasm from central Italy and identified a ‘core collection’ representative of the present genetic diversity. A total of 161 trees, morphologically identified as var. austera, and one tree, identified as var. caproniana were collected and genotyped by 14 SSRs. Two individuals provided by a commercial plant nursery, one of P. cerasus var. caproniana and one of P. cerasus var. austera, were used as control. Thirteen SSRs presented private alleles in austera. Seven individuals morphologically identified as austera revealed private alleles specific to caproniana. The PCoA and Bayesian clustering analysis showed a main genetic group including var. austera, while a second group included all the caproniana-like genotypes. A core collection of 31 trees (46% of austera genotypes) was selected. This study can be considered as a starting point for future investigations on this variety.  相似文献   
89.
【目的】从兰州唐古特白刺根际分离得到对植物有潜在促生效果的功能微生物,为研发相关菌种制剂的研究奠定基础。【方法】通过平板划线法从其根际分离纯化出6株细菌,并对菌株进行形态特征观察、革兰氏染色等一系列生理生化试验。用藜麦检测各菌株的促生功能,并对具有优良促生作用的1个菌株16S rRNA基因进行分子鉴定及基因草图绘制。【结果】根据生化鉴定结果,6株细菌分别属于不动杆菌属(Acinetobacter)、土壤杆菌属(Agrobacterium)、类芽孢杆菌属(Paenibacillus)、芽孢杆菌属(Bacillus)、鞘氨醇单胞菌属(Sphingomonas)和假单胞菌属(Pseudomonas)。其中,16S rRNA基因鉴定BC4属于肠杆菌属(Enterobacter),具有较好的促生效果。【结论】BC4具有较好的促生效果,为兰州唐古特白刺菌种资源的开发和利用提供了一定的理论依据。  相似文献   
90.
Phosphatidylinositol 3-kinase-related protein kinases (PIKKs) play critical roles in various metabolic pathways related to cell proliferation and survival. The TELO2-TTI1-TTI2 (TTT) complex has been proposed to recognize newly synthesized PIKKs and to deliver them to the R2TP complex (RUVBL1-RUVBL2-RPAP3-PIH1D1) and the heat shock protein 90 chaperone, thereby supporting their folding and assembly. Here, we determined the cryo-EM structure of the TTT complex at an average resolution of 4.2 Å. We describe the full-length structures of TTI1 and TELO2, and a partial structure of TTI2. All three proteins form elongated helical repeat structures. TTI1 provides a platform on which TELO2 and TTI2 bind to its central region and C-terminal end, respectively. The TELO2 C-terminal domain (CTD) is required for the interaction with TTI1 and recruitment of Ataxia-telangiectasia mutated (ATM). The N- and C-terminal segments of TTI1 recognize the FRAP-ATM-TRRAP (FAT) domain and the N-terminal HEAT repeats of ATM, respectively. The TELO2 CTD and TTI1 N- and C-terminal segments are required for cell survival in response to ionizing radiation.  相似文献   
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