中国各省环境效率及环境效率幻觉分析

为了更准确地了解我国经济发展质量,深刻理解环境效率的含义,本文以全新视角对中国各省环境效率进行测量、分析。首先,基于中国各省农业和工业生产要素投入、期望产出和非期望产出,利用二次型方向性距离函数和收益函数的对偶关系,测算2011年至2013年中国大陆31个省份污染物的影子价格。其次,利用影子价格衡量污染物减排边际成本的优点,根据世界可持续发展工商理事会(WBCSD)提出的环境效率测度公式,研究各省的环境负荷、环境效率,针对环境效率在衡量经济发展质量过程中的缺陷,提出环境效率幻觉概念,结合二者对全国各省进行综合评判,结果表明:全国范围内的各省环境效率值基本呈逐年递增趋势;整体上环境效率值在东中西部呈递减,但东北各省的环境效率值已普遍低于西南各省,且差距有扩大的趋势;出现环境效率幻觉的省份较少,但随着经济"新常态"的出现,其数量在增加。再次,利用环境效率的上升和环境效率幻觉的下降判断,中国仅二分之一的省份环境质量在真正好转。最后,环境效率影响因素的分析表明:全国范围内,产业结构、人均收入以及对外贸易水平与环境效率正相关,政府规制与环境效率负相关,对各地区的影响却呈现出较大差异;政府规制在东部和中部地区对环境效率具有促进作用,且东部大于中部,而西部地区却存在负效应;产业结构在中部和西部地区对环境效率具有积极的促进作用,且西部大于中部,但是东部地区却存在着负效应;对外贸易的继续增加对东中部地区环境效率具有消极的影响,且东部大于中部,对西部地区环境效率有积极的促进作用。     

A novel Dempster-Shafer theory-based approach with weighted average for failure mode and effects analysis under uncertainty

Risk priority number (RPN) is a commonly-used prioritization method in failure mode and effects analysis (FMEA) for systemic reliability and safety study. However, conventional RPN confronts wide criticisms, due to the neglect of the uncertainties of experts' opinions. It is important to handle the conflicts among experts' multi-opinions which could be described in imprecise, incomplete or crisp forms in lack of knowledge. In this paper, a novel method is proposed to alleviate and/or eliminate counter-intuitive behaviors against conflicts among multi-opinions under Dempster-Shafer theory. Firstly, the abnormity test for experts’ opinions is undertaken to identify and discard those distinct judgments. Then, an approach to determining the subjective weights of experts is proposed, which is used in weighted average for multi-opinions before calculating RPNs. Finally, the risk priority evaluation on main engine crankcase explosion failure on-board ship is implemented to verify the feasibility of the proposed approach.     

Screening for antioxidant and detoxification responses in Perna canaliculus Gmelin exposed to an antifouling bioactive intended for use in aquaculture

Polygodial is a drimane sesquiterpene dialdehyde derived from certain terrestrial plant species that potently inhibits ascidian metamorphosis, and thus has potential for controlling fouling ascidians in bivalve aquaculture. The current study examined the effects of polygodial on a range of biochemical biomarkers of oxidative stress and detoxification effort in the gills of adult Perna canaliculus Gmelin. Despite high statistical power and the success of positive controls, the antioxidant enzymes glutathione reductase (GR), glutathione peroxidase (GPOX), catalase (CAT), and superoxide dismutase (SOD); thiol status, as measured by total glutathione (GSH-t), glutathione disulphide (GSSG), and GSH-t/GSSG ratio; end products of oxidative damage, lipid hydroperoxides (LHPO) and protein carbonyls; and detoxification pathways, represented by GSH-t and glutathione S-transferase (GST), were unaffected in the gills of adult P. canaliculus exposed to polygodial at 0.1 or 1 × the 99% effective dose in fouling ascidians (IC₉₉). Similarly, GR levels, thiol status, and detoxification activities were unaffected in mussels exposed to polygodial at 10 × the IC₉₉, although GPOX, CAT, and SOD activities increased. However, the increases were small relative to positive controls, no corresponding oxidative damage was detected, and this concentration greatly exceeds effective doses required to inhibit fouling ascidians in aquaculture. These findings compliment a previous study that established the insensitivity to polygodial of P. canaliculus growth, condition, and mitochondrial functioning, providing additional support for the suitability of polygodial for use as an antifouling agent in bivalve aquaculture.     

Behavior of the organophosphorus insecticide fenitrothion in stored faba beans and its biological effects towards experimental animals

Sound whole-seed faba beans were treated with (methyl-¹⁴C) fenitrothion [O, O-dimethyl-O-(3-methyl-4-nitrophenyl) phosphorothioate] at 5 and 10 mg insecticide/kg seeds, a dose normally used in practice. During the 30 weeks of storage period, the penetration and distribution of insecticide residues were studied. The amount of surface residues, internal residues and bound insecticide residues was estimated. Surface residues were found to decrease with the increase in time of storage, whereas internal residues showed a gradual increase with time apparently not dose dependent. Grain-bound residues increased with time and reached to its maximum (14–18%) after 24 weeks of storage. Chromatographic analysis of the internal extracts revealed the presence of the parent compound together with three main metabolites which were found in both free and conjugated form. Feeding mice for 90 days with a diet mixed with total internal fenitrothion residues in stored faba beans led to a reduction in body weight gain, and an appreciable decrease in cholinesterase activity of 32% for plasma and 15% for red blood cells (RBC_S) after two months of experiment. Also, a significant decrease was showed in both total protein and albumin concentration at the end of feeding period (90 days). Liver and kidney function, as well as lipid profile of treated mice significantly increased at the end of feeding period. After a one-month recovery period, all the examined blood parameters returned to about the control values except blood urea and serum triglyceride.     

The effects of ammonium sulphate and urea upon egg hatching and miracidial survival of Schistosoma mansoni

Abstract

The effects of various concentrations of ammonium sulphate and urea on egg hatching and miracidial survival of S. mansoni were tested in order to determine if the use of these fertilizers in the ricelands of the Republic of Cameroon could affect the transmission of schistosomiasis. Results indicate that hatching of eggs and survival of miracidia varied with concentrations of tested chemicals and times of exposure. Exposure of S. mansoni eggs to 0.20%‐1.00% ammonium sulphate or to 0.50%‐4.00% urea reduced their ability to hatch and produce miracidia. A chemical concentration of 1.00% ammonium sulphate or 4.00% urea was found to be sufficient to produce complete inhibition of hatching. High concentrations of both chemicals not only inhibited miracidial emmergence but also may be ovocidal. Results obtained from miracidial survival tests indicated that LC₅, LC₅₀ and LC₉₅ values for ammonium sulphate were 0.07%, 0.80% and 10.61% after 2 hours of exposure; 0.03%, 0.16% and 0.90% after 4 hours of exposure; and 0.30%, 0.20% and 0.40% after 6 hours of exposure respectively. Similar statistical analyses revealed that the LC₅, LC₅₀ and LC₉₅ values for urea were 0.22%, 1.90% and 16.25% after 2 hours of exposure; 0.28%, 0.57% and 1.14% after 4 hours of exposure; and 0.13%, 0.27% and 0.57%” after 6 hours of exposure respectively. Although the two fertilizers exerted some adverse effects on S. mansoni eggs and miracidia at relatively high concentrations, neither of them was found to be of practical value. Ammonium sulphate and urea concentrations effective in killing S. mansoni eggs and miracidia were about one to two orders of magnitude greater than the actual field application rates.     

Abundance and diversity of aquatic macroinvertebrate communities in lakes exposed to Chernobyl-derived ionising radiation

Littoral (lake shore) macroinvertebrate communities were studied in eight natural lakes affected by fallout from the Chernobyl accident. The lakes spanned a range in ¹³⁷Cs contamination from 100 to 15500 kBq m⁻² and estimated external dose rates ranged from 0.13 to 30.7 μGy h⁻¹. General linear models were used to assess whether abundance of individuals, taxon richness, Berger-Parker dominance and Shannon-Wiener diversity varied across the lakes. Step-wise multiple regressions were used to relate variation in total abundance, taxon richness, Berger-Parker dominance, Shannon-Wiener diversity, taxon richness within major groups of macroinvertebrates and abundance of the more common individual taxa to the measured environmental characteristics (conductivity, pH, total hardness and phosphate; lake area, lake maximum depth and total external dose) of the lakes. No evidence was found in this study that the ecological status of lake communities has been influenced by radioactive contamination from the Chernobyl accident. Indeed, the most contaminated lake, Glubokoye, contained the highest richness of aquatic invertebrates. Taxon richness in the eight study lakes varied from 22 (Svyatskoe #7) to 42 (Glubokoye) which spans a range typical for uncontaminated lakes in the region. Since ⁹⁰Sr is readily-absorbed by Mollusca, estimated dose rates to this group exceeded those for other invertebrate groups in two lakes (Perstok and Glubokoye). However this study found no association between mollusc diversity or abundance of individual snail species and variation between lakes in the external radiation dose. Indeed Glubokoye, the lake most contaminated by ⁹⁰Sr, had the highest richness of freshwater snails per sample (an average of 8.9 taxa per sample).     

石油烃对翅碱蓬生理特性的影响及植物-微生物联合降解

通过盆栽实验,测定在低浓度石油烃浓度下翅碱蓬的生长生理指标及沉积物和翅碱蓬中石油烃含量的变化,研究石油烃对翅碱蓬生理特性和抗氧化酶系统的影响及植物-微生物联合修复效果。结果表明,翅碱蓬抗氧化酶能够快速提高活性来抵御逆境,植株还可通过增加其叶绿素含量等来适应或补偿逆境造成的损失。同时还发现,当植物处于石油烃污染沉积物时,它体内污染物的分布会与自然情况下有所不同,自然情况下分布为茎>叶>根,受污染时分布为根>茎>叶,该结果可以作为判断沉积物是否受到污染的依据。实验的不同处理(加植物加菌组、只加菌未种植物组、种植物未加菌组)去除率分别为70.87%、63.66%和60.26%,翅碱蓬-降解菌处理的沉积物中石油烃残留浓度最低、去除量最高,表明植物-微生物联合作用更有利于石油烃污染沉积物的修复。     

国内外少数民族村寨旅游研究进展

近年来,少数民族村寨的旅游发展引起了社会各界的广泛关注,旅游者对其兴趣浓厚,倍加青睐,国内外学者们纷纷探讨了适合少数民族村寨旅游发展的道路.归纳发现,国内外学者在研究内容上存在着一定的差异,通过总结他们集中探讨的问题,给我国少数民族村寨旅游发展提供一定的借鉴.     

19种动植物粗提物对锦鲤诱食活性的研究

以16种植物和3种动物提取物作为实验材料,以体长为3—5cm的锦鲤为实验对象,采用触球法进行诱食活性研究,5次重复试验,并利用SPSS软件进行分析。结果表明,大蒜、浒苔、洋葱、西红柿、江蓠、陈皮、橙子、山楂、紫菜提取物和海星、海蜇、牡蛎提取物对锦鲤显示出诱食反应。其中,大蒜P=0.0010.05、浒苔P=0.0020.05、江蓠P=0.0040.05、陈皮P=0.0370.05、海星P=0.0030.05,说明大蒜、浒苔、江蓠、陈皮、海星对锦鲤的诱食反应有显著意义。     

从说课看高职高专院校学情

高职高专学生由于特定的生理和心理特点,在选修体育课程过程中出现随群现象,学习积极性不高。通过说课对高职高专院校的学情加以分析,以便科学地、有目地、有针对性地安排教学内容,增强学生的自信心,提高他们的心理素质和身体素质。