Air pollution and COPD in China

Recently, many researchers paid more attentions to the association between air pollution and chronic obstructive pulmonary disease (COPD). Haze, a severe form of outdoor air pollution, affected most parts of northern and eastern China in the past winter. In China, studies have been performed to evaluate the impact of outdoor air pollution and biomass smoke exposure on COPD; and most studies have focused on the role of air pollution in acutely triggering symptoms and exacerbations. Few studies have examined the role of air pollution in inducing pathophysiological changes that characterise COPD. Evidence showed that outdoor air pollution affects lung function in both children and adults and triggers exacerbations of COPD symptoms. Hence outdoor air pollution may be considered a risk factor for COPD mortality. However, evidence to date has been suggestive (not conclusive) that chronic exposure to outdoor air pollution increases the prevalence and incidence of COPD. Cross-sectional studies showed biomass smoke exposure is a risk factor for COPD. A long-term retrospective study and a long-term prospective cohort study showed that biomass smoke exposure reductions were associated with a reduced decline in forced expiratory volume in 1 second (FEV₁) and with a decreased risk of COPD. To fully understand the effect of air pollution on COPD, we recommend future studies with longer follow-up periods, more standardized definitions of COPD and more refined and source-specific exposure assessments.     

甘草种苗等级与植株生物量积累及药材产量和质量的关系

目的:研究甘草种苗等级与植株生物量积累、药材产量和质量的关系,为制定种苗标准提供依据。方法:以单根重量为分级指标对甘草种苗进行分级,采用聚类分析方法将种苗聚类分级为3个级别,以级别为处理进行田间试验,连续两年于生长期测定甘草植株鲜重和根干重,实验室测定药材有效成分含量。结果:一级、二级种苗(单根重10.0 g以上)生长期植株的总生物量、根干物质量及产量均大于三级种苗。3年生药材的甘草酸、甘草苷、芹糖基甘草苷和甘草素的含量,一、二级种苗高于三级种苗;不同等级种苗药材甘草酸和甘草苷的含量均高于2010年版中国药典一部标准。结论:种苗等级对甘草药材的质量及产量均有影响,生产上建议选用单根重在10.0g以上的种苗。     

Pulmonary changes on HRCT scans in nonsmoking females with COPD due to wood smoke exposure

OBJECTIVE:

To identify and characterize alterations seen on HRCT scans in nonsmoking females with COPD due to wood smoke exposure.

METHODS:

We evaluated 42 nonsmoking females diagnosed with wood smoke-related COPD and 31 nonsmoking controls with no history of wood smoke exposure or pulmonary disease. The participants completed a questionnaire regarding demographic data, symptoms, and environmental exposure. All of the participants underwent spirometry and HRCT of the chest. The COPD and control groups were adjusted for age (23 patients each).

RESULTS:

Most of the patients in the study group were diagnosed with mild to moderate COPD (83.3%). The most common findings on HRCT scans in the COPD group were bronchial wall thickening, bronchiectasis, mosaic perfusion pattern, parenchymal bands, tree-in-bud pattern, and laminar atelectasis (p < 0.001 vs. the control group for all). The alterations were generally mild and not extensive. There was a positive association between bronchial wall thickening and hour-years of wood smoke exposure. Centrilobular emphysema was uncommon, and its occurrence did not differ between the groups (p = 0.232).

CONCLUSIONS:

Wood smoke exposure causes predominantly bronchial changes, which can be detected by HRCT, even in patients with mild COPD.     

Fe/活性炭催化剂上合成气合成液体燃料

以活性炭为载体,钾为助剂,浸渍法制备了Fe/活性炭催化剂,在固定床反应器中考察了不同铁含量、助剂、载体的催化剂的催化性能。结果表明Fe/椰壳活性炭具有较高的一氧化碳转化率和C+5烃收率。考察了反应温度、压力、空速等对费-托合成的影响。在Fe/椰壳活性炭催化剂上,适宜的温度(300～350°C),中压(2.5MPa)及较低空速(1000h-1)有利于合成气合成液体燃料。     

Caudal brain stem plays a role in metabolic control of estrous cycles in Syrian hamsters

In Syrian hamsters, a critical factor necessary for the occurrence of normal estrous cycles appears to be the cellular availability of oxidizable glucose. For example, estrous cycles are inhibited by food deprivation or treatment with 2-deoxy- -glucose (2DG), a drug that inhibits cellular glucose utilization. Several lines of evidence suggest that these effects require the participation of neurons in part of the caudal brain stem, the area postrema (AP) and adjacent, reciprocally-innervated nucleus of the solitary tract (NTS). This study was designed to examine the role of the AP in 2DG-induced anestrus. Hamsters received either aspiration lesions directed at the AP or sham operations. Between 12 and 16 days after surgery, both sham-operated and lesioned hamsters showed two consecutive 4-day estrous cycles, as measured by estrous behavior and vaginal discharge. Subsequently, both groups were treated with doses of 2DG known to inhibit the estrous cycle (1750 mg/kg every 6 h on days 1 and 2 of the cycle). Hamsters were tested for measures of estrous cyclicity daily after treatment. Only 9% of the sham-operated hamsters showed estrous cycles within 5 days after the start of 2DG treatment. In contrast, all of the hamsters with confirmed lesions of the AP showed estrous cycles within 5 days of the start of 2DG treatment. Histology showed that most lesions removed the AP plus part of the medial NTS, while two lesions removed part of the AP only. These results are consistent with the idea that the AP, and possibly the NTS, play a role in the effects of decreased glucose availability on estrous cycles in Syrian hamsters.     

Nycthemeral variation in brain monoamines of Syrian hamsters: relation to activity and energy homeostasis

No significant time-of-day variations were found in whole brain content of various monoamines and metabolites of sedentary Syrian hamsters. In a second experiment, norepinephrine and serotonin levels in diencephalon were higher in the morning than the evening of both sedentary and voluntarily exercising hamsters. In telencephalon, levels of most transmitters were elevated in the evening, with the most dramatic rises in the metabolites 3,4-dihydroxyphenylacetic acid and 5-hydroxyindoleacetic acid. Again, in most instances, there was no difference between sedentary and exercise conditions.     

Vermiconversion of wastewater sludge from textile mill mixed with anaerobically digested biogas plant slurry employing Eisenia foetida

Vermicomposting is commonly used for the management of organic wastes. We have investigated the potential of an epigeic earthworm, Eisenia foetida, to transform solid textile mill sludge (STMS) spiked with anaerobically digested biogas plant slurry (BPS) into vermicompost to evaluate the feasibility of vermicomposting in industries for waste management. The growth and reproduction of E. foetida was monitored in a range of different feed mixtures for 15 weeks in laboratory under controlled experimental conditions. E. foetida did not survive in fresh STMS. But worms grew and reproduced in STMS spiked with BPS feed mixtures. A greater percentage of STMS in feed mixture affected biomass gain and cocoon production by earthworms. The maximum growth was recorded in 100% BPS. The net weight gain by E. foetida in 100% BPS was two-four-fold higher than STMS-containing feed mixtures. After 15 weeks, maximum cocoons (78) were counted in 100% BPS and minimum (26) in 60% BPS+40% STMS feed. Vermicomposting resulted in pH shift toward acidic, significant reduction in C:N ratio, and increase in nitrogen, phosphorus, and potassium contents. Microbial activity measured as dehydrogenase activity increased with time up to day 75 but decreased on day 90, indicating the exhaustion of feed and decrease in microbial activity. These experiments demonstrate that vermicomposting can be an alternate technology for the recycling and environmentally safe disposal/management of textile mill sludge using an epigeic earthworm, E. foetida, if mixed with anaerobically digested BPS in appropriate ratios.     

流量可调燃气发生器压力闭环模糊控制算法

为了改进流量可调燃气发生器的调节精度,引入燃气发生器压力闭环控制,针对流量可调燃气发生器压力闭环控制特点,在压力闭环中引入了模糊积分控制,此控制算法响应速度快,超调量较小,不同工况及长时间工作下系统仍然有较好的动态特性。      

扩展角对Diamond-Jet型超音速火焰喷涂流场的影响

采用计算流体力学方法对超音速火焰喷涂过程进行数值模拟,研究了扩展角的变化对燃烧场的影响。研究发现扩展角对马赫锥形成的位置具有影响,随着扩展角的变化,马赫锥产生的位置向燃烧室方向偏移,当扩展角为0°~3.0°时,最大马赫数随扩展角度增大而增大。研究了扩展角对Diamond Jet喷枪的温度场影响,当扩展角为0°~1.0°时,温度随扩展角的增加而降低,燃烧能转化为气体的动能;但是当扩展角度继续增加时,温度不再降低。     

Passive smoke exposure induces oxidative damage in brains of rat pups: Protective role of diphenyl diselenide

The protective effect of diphenyl diselenide, (PhSe)₂, on oxidative stress induced by cigarette smoke exposure in brains of rat pups was evaluated. Animals were exposed to passive cigarette smoke (15?min/day) in two different experimental protocols: P1 (1, 2, and 3 cigarettes) and P2 (4, 5, and 6 cigarettes) for 3 weeks. Before each period of smoke exposure, animals received an oral administration of (PhSe)₂ (0.5?mg/kg). A number of toxicological parameters in the brain were examined, such as lipid peroxidation, δ-aminolevulinate dehydratase (δ-ALA-D) activity, and components of enzymatic (superoxide dismutase and catalase activities) and non-enzymatic antioxidant defenses (ascorbic acid and non-protein thiol levels). In P1, smoke exposure induced an inhibition of catalase activity and an increase of ascorbic acid levels. (PhSe)₂ treatment was able to protect catalase activity but not ascorbic acid levels. In P2, an augmentation of lipid peroxidation, a reduction of enzymatic and non-enzymatic antioxidant status, and an inhibition of δ-ALA-D activity caused by smoke exposure were found. (PhSe)₂ protected the brains of rat pups against oxidative damage induced by smoke exposure. The results are consistent with the antioxidant effect of (PhSe)₂ demonstrated by the reduction of oxidative changes caused by smoke exposure in the brains of pups.