Carbon dioxide emissions in OECD service sectors: the critical role of electricity use

From the early 1970s to mid 1990s, service sector CO₂ emissions have increased significantly in OECD countries, despite marked declines in energy intensity. This development is underscored by a widespread shift from fuel use to electricity use in commercial buildings. Service sectors in countries that produce low-carbon electricity, particularly those that operate nuclear- and hydro-powered utilities, have most successfully restrained CO₂ emissions. This study analyzes the impact of activity, structure, energy intensity, fuel mix, and utility mix on carbon emissions in the service sector for 13 OECD countries, and contrasts the developments before 1990 with those afterwards. The major findings of this analysis are:

(i) Carbon emissions, which rose in 9 of the 13 countries investigated, were bolstered in every country by an expansion of floor area and service sector GDP,

(ii) Declines in energy intensity and carbon intensity lessened the magnitude of emissions increases,

(iii) Electricity's share of final energy use rose in all 13 countries, but affected carbon emissions quite differently among countries,

(iv) After 1990, energy intensity improvements applied less downward pressure on emissions, while reductions in the average carbon content of final energy restrained emissions more strongly.     

Microbial community functional structure in response to antibiotics in pharmaceutical wastewater treatment systems

It is widely demonstrated that antibiotics in the environment affect microbial community structure. However, direct evidence regarding the impacts of antibiotics on microbial functional structures in wastewater treatment systems is limited. Herein, a high-throughput functional gene array (GeoChip 3.0) in combination with quantitative PCR and clone libraries were used to evaluate the microbial functional structures in two biological wastewater treatment systems, which treat antibiotic production wastewater mainly containing oxytetracycline. Despite the bacteriostatic effects of antibiotics, the GeoChip detected almost all key functional gene categories, including carbon cycling, nitrogen cycling, etc., suggesting that these microbial communities were functionally diverse. Totally 749 carbon-degrading genes belonging to 40 groups (24 from bacteria and 16 from fungi) were detected. The abundance of several fungal carbon-degrading genes (e.g., glyoxal oxidase (glx), lignin peroxidase or ligninase (lip), manganese peroxidase (mnp), endochitinase, exoglucanase_genes) was significantly correlated with antibiotic concentrations (Mantel test; P < 0.05), showing that the fungal functional genes have been enhanced by the presence of antibiotics. However, from the fact that the majority of carbon-degrading genes were derived from bacteria and diverse antibiotic resistance genes were detected in bacteria, it was assumed that many bacteria could survive in the environment by acquiring antibiotic resistance and may have maintained the position as a main player in nutrient removal. Variance partitioning analysis showed that antibiotics could explain 24.4% of variations in microbial functional structure of the treatment systems. This study provides insights into the impacts of antibiotics on microbial functional structure of a unique system receiving antibiotic production wastewater, and reveals the potential importance of the cooperation between fungi and bacteria with antibiotic resistance in maintaining the stability and performance of the systems.     

我国饲料中的真菌和真菌毒素

从全国各地采集271份样品,包括231份饲料和40份原料。其中205份饲料和29份原料检测了带菌量和菌相;同时还检测了216份饲料和38份原料中的四种真菌毒素。分离鉴定出25属83种真菌,包括毛霉目11种、青霉属28种、曲霉属23种、镰刀菌属2种和其它真菌19种。正常粉状饲料带菌量为10~3～10~4个/克;颗粒饲料带菌量为10~1～10~3个/克;霉变粉状饲料带菌量为10~6～10~7个/克;霉变颗粒料带菌量为10~4个/克以上。有92%的样品检出曲霉属;有73%的样品检出青霉属:有37%的样品检出串珠镰刀菌;有33%的样品检出毛霉属。在曲霉属中灰绿曲霉群,黄曲霉群和白曲霉群的检出频率分别达到75.9%、72.2%和67.5%。在青霉属中主要有产黄青霉、桔青霉、纯绿青霉和圆弧青霉。在饲料和原料中,黄曲霉毒素 B_1(AFB_1)的检出率分别为2.8%、28%,最高含量分别为220ppb、1756.6ppb;黄曲霉毒素 G_1(AFG_1)的检出率分别为0.4%、5.3%,最高含量分别为16.4ppb、34.4ppb;棕曲霉毒素 A(OA)的检出率分别为4.2%、2.6%,最高含量为1512ppb、19.4ppb;脱氧雪腐镰刀菌烯醇(DON)的检出率分别为12%、13.2%,最高含量为1044ppb、1111.2ppb。黄曲霉毒素主要污染广西和广东的样品。脱氧雪腐镰刀菌烯醇的污染较广泛。     

Antimicrobial activity of essential oil extracts of various onions (Allium cepa) and garlic (Allium sativum)

Antimicrobial activity of different concentrations (50, 100, 200, 300 and 500 ml/l) of essential oil extracts of three type of onions (green, yellow and red) and garlic against two bacteria, Staphylococcus aureus, Salmomella Enteritidis, and three fungi, Aspergillus niger, Penicillium cyclopium and Fusarium oxysporum, was investigated. The essential oil (EO) extracts of these Allium plants (garlic and onions) exhibited marked antibacterial activity, with garlic showing the highest inhibition and green onion the lowest. Comparatively, 50 and 100 ml/l concentrations of onions extracts were less inhibitory than 200, 300 and 500 ml/l concentrations. However, with garlic extract, high inhibitory activity was observed for all tested concentrations. S. aureus showed less sensitivity towards EO extracts inhibition, however S. Enteritidis was strongly inhibited by red onion and garlic extracts. The fungus F. oxysporum showed the lowest sensitivity towards EO extracts, whereas A. niger and P. cyclopium were significantly inhibited particularly at low concentrations. Conclusively, where seasoning is desired, essential oil extracts of onions and garlic can be used as natural antimicrobial additives for incorporating in various food products.     

2005年东莞市食用菌甲醛含量抽查结果分析

目的了解东莞市农贸市场食用菌中甲醛的残留情况。方法对东莞市32个镇区35个农贸市场进行抽查。共抽查130份食用菌,其中干香菇56份,银耳58份,木耳14份,茶树菇2份。结果在干香菇中甲醛检出率100%,平均值164 mg/kg。可能是香菇中甲醛本底值高和生产环节中的工艺所致。木耳、银耳和茶树菇中未检出甲醛。结论食用菌中甲醛的存在有多种因素,在监督中应慎下结论。     

印度梨形孢真菌促进芝麻生长并提高芝麻抗旱性

将印度梨形孢（Piriformospora indica,Pi）真菌接种芝麻幼苗根部,分别在大田及温室条件下研究供试真菌对芝麻生长和抗旱性的效应。大田试验主要调查产量性状,温室试验在芝麻初花期进行15d的持续干旱处理,测定株高等形态性状、过氧化氢酶活性等生理指标。结果表明,接种及未接种只真菌的芝麻植株在干旱处理前后叶长、叶宽差异达到极显著水平,株高、全展叶片数、基部茎粗、叶绿素含量、根颈粗差异达到显著水平;在人工干旱胁迫条件下,接种尉真菌后芝麻植株能维持较高的过氧化氢酶（CAT）活性和较高含量的脯氨酸（Pro）,降低丙二醛（MDA）含量,从而减轻干旱胁迫伤害。在千粒重及单株籽粒重两个产量性状上,大田和温室接种的芝麻与未接种的差异均达到显著水平。接种成真菌不仅能促进芝麻的生长,而且在干旱条件下,使得芝麻表现出较强的抗旱性,显著提高芝麻产量。     

干旱生境中VA菌根对宿主植物的影响及其机制

试验研究证明VA菌根可以影响宿主植物的水分关系。文章综述了VA菌根在干旱胁迫条件下对宿主植物形态、代谢、渗透适应的影响以及VA菌根可能提高宿主抗/耐旱性的机制。文章认为,VA菌根有利于宿主植物抗/耐旱性的作用是由于物理的、化学的、生理的、细胞的综合作用的结果。     

Effect of honey high-temperature short-time heating on parameters related to quality, crystallisation phenomena and fungal inhibition

The effect of a unique high-temperature short-time heating treatment on natural honeys to produce both a fungi inhibition and a crystallisation delay simultaneously was evaluated. As responses to treatments, hydroxymethylfurfural content, diastase activity, fungi and yeast development, and crystallisation starting time were measured. Besides, moisture, fructose, glucose and acidity were determined.Heating can produce a decrease in honey quality, which is made evident by a simultaneous reduction in the diastase activity, referred to as diastase number, and an increase in the hydroxymethylfurfural content. Considering the minimum admissible diastase number and the maximum admissible hydroxymethylfurfural content values, according to honey present regulations, several thermal treatment tests were performed on selected honey samples without exceeding those values. Tested conditions were: heating between 140°C and 80°C at times between 60 to 15 s and 30 to 10 s during both transient and isothermal heating stages, respectively. In all tests the diastase number was the most heat-sensitive parameter. The boundary thermal treatment, assumed as the most severe conditions able to produce a permissible quality loss, was found to be 140°C, during 15 s in the transient stage and 30 s in the isothermal stage. Beyond those values, an unacceptable diastase number reduction was produced. On the other hand, it was found that a 80°C heating, during 60 and 30 s in transient and in isothermal stages, respectively, destroyed all microorganisms responsible for quality damage without spoiling honey. This was considered to be the mild or more suitable treatment condition. Twenty-six naturally contaminated honey samples heated at such conditions showed a null capacity to develop fungi and yeast. Besides, according to the storing temperature, and moisture and glucose contents, a crystallisation beginning delay between 4 and 9 weeks was obtained on four selected honeys, according to the thermal treatment applied. Several parameters previously proposed that characterise honey crystallisation tendency as fructose/glucose, glucose/moisture and (glucose-moisture)/fructose ratios were related to the time in which crystallisation starts. A new parameter, (fructose/glucose)·moisture was proposed.