Curcumin antagonizes inflammation and autophagy induced by arsenic trioxide through immune protection in duck spleen

Environmental Science and Pollution Research - Arsenic is a toxic heavy metal widely found in the natural environment and has adverse effects on the health of waterfowl and human. Curcumin (CUR), a...     

Bacterial abundance and community structure in response to nutrients and photodegraded terrestrial humic acids in a eutrophic lake

The exposure of humic substances to solar radiation can alter their concentration and composition and subsequently influences their bioavailability in aquatic food webs. With eutrophication increasingly prominent in lakes, nutrients, such as inorganic N and P, are a prerequisite for heterotrophic bacteria that use organic matter. Here photodegradation of terrestrial humic acids and nutrient addition were performed to investigate the response of bacterial abundance and community structure to photodegraded humic acids and increased nutrient concentrations in a eutrophic lake. Results showed that the decreasing level of absorption coefficient at 460 nm in the treatment irradiated with 40 W UV lamps was more remarkable than that of the treatment irradiated with 20 W UV lamps and the control. This reduced coefficient corresponds to the greatest decrease in humic acid concentration in the 40 W group. Bacteria showed high abundance after incubation with humic acids which underwent strong irradiation intensity. An increased nutrient concentration significantly affected bacterial abundance. The dominant bacteria were Aquabacterium for the irradiated group, Aquabacterium and Limnobacter for the 20 W group and Flavobacterium and Limnobacter for the 40 W group. Armatimonadetes-gp4 and Sediminibacterium showed evident response to high nutrient concentration. Our results showed that the exposure of terrestrial humic acids to UV light and the increasing concentration of nutrients have obviously changed bacterial community.

     

北京市北沙河上游典型小流域水环境治理措施的生态效益分析

北京市属于资源型重度缺水地区,水资源紧缺严重制约其可持续发展,加之水质恶化,造成了全市水资源和水环境形势严峻的局面.为此,北京市布设相应措施对小流域水环境问题进行治理,分析治理措施的生态效益能够为小流域水环境治理措施的合理布设提供科学依据.以北京市昌平区北沙河上游8条小流域为研究区,基于In VEST(Integrat...     

Environmental consequences of different beef production systems in the EU

The aim of this paper is to examine the environmental consequences of beef meat production in the EU, using a life cycle approach. Four beef production systems were studied – three from intensively reared dairy calves and one from suckler herds. According to the results of the analysis, the contributions from the production of 1 kg beef meat (slaughter weight) to global warming, acidification, eutrophication, land use and non-renewable energy use were lower for beef from dairy calves than from suckler herds (16.0–19.9 versus 27.3 kg CO₂e, 101–173 versus 210 g SO₂e, 622–1140 versus 1651 g NO₃e, 16.5–22.7 versus 42.9 m²year, and 41.3–48.2 versus 59.2 MJ, respectively). The breakdown analysis helped identify the key areas in the “cradle to farm gate” beef production system where sustainable management strategies are needed to improve environmental performance. The study also included a sensitivity analysis to preliminarily estimate GHG emissions from beef production systems if land opportunity cost and land use change related to grazing and feed crop production for beef were taken into account. If so, the contribution from the production of 1 kg beef to global warming would increase by a factor of 3.1–3.9, based on a depreciation period of 20 years. This highlights the importance of taking into account the impacts of land use in assessing the environmental impacts of livestock production.     

硅钼黄法测定海水中硅消除P干扰的研究

Si和P与钼酸铵反应均能生成钼黄,为了消除P对Si的干扰,国家标准采用加草酸溶液方法,研究发现该溶液不但破坏磷钼黄,也破坏硅钼黄,且反应速度很快,比色必须在2 min内完成,否则结果大大偏低。我们也用酒石酸溶液替代草酸溶液,虽然破坏硅钼黄速度减慢,但也不理想。本文通过实验推导和验证:如果已知P浓度,把测得的Si、P总浓度减去P的浓度乘0.389所得的值,就消除了P的干扰,方法简便准确。     

当前排污费征收中的问题和发展方向

本文针对在2000年“一控双达标”工作后排污费征收中出现的问题，提出了相应的解决办法，同时对排污费今后的发展作了简要阐述。     

钙信号对镉诱导河南华溪蟹细胞凋亡的调控

以河南华溪蟹(Sinopptamon henanense)为研究材料,采用生理生化和酶学组织化学等方法,通过不同时间(12、24、48、72和96 h)不同镉浓度(0、14.5、29、58 mg·L-1)处理,首先研究了镉对肝胰腺细胞内钙调素(CaM)含量、钙ATP酶(Ca2+-ATPase)活性和细胞凋亡的影响;然后用Ca2+抑制剂EGTA和LaCl3预处理河南华溪蟹后再进行镉处理,以分析Ca2+信号对镉诱导肝胰腺细胞凋亡的影响.结果显示,镉处理引起肝胰腺细胞CaM含量和Ca2+-ATPase活性显著升高,并且Caspase-3和Caspase-9被激活.用Ca2+抑制剂EGTA和LaCl3预处理华溪蟹4 h后,再用镉处理48 h,镉诱导的肝胰腺细胞Caspase-3和Caspase-9活性上升都被阻断.结果表明:镉处理引起河南华溪蟹肝胰腺细胞Ca2+浓度发生变化,并通过CaM等信号分子调控Caspase-3/9活性,进而引发细胞凋亡.     

陕西省石煤提钒行业存在的问题及对策研究

陕西的石煤主要分布在陕南秦岭南坡的商洛地区,但大部分石煤钒矿属于难处理矿,钒大部分以V（Ⅲ）和V（Ⅳ）存在,目前企业大多采用“焙烧＋稀酸浸出＋氨法沉钒”或者“强酸浸出＋氨法沉钒”工艺进行生产。存在的问题一是钒的综合回收率为65％左右,整体偏低;二是生产废水中含有大量氨使得废水闭路循环难度大;三是矿区大部分位于汉丹江水系的中上游地区或临近出省断面,选址较为敏感。针对以上存在的问题提出了解决建议．并对陕西省石煤提钒行业的发展做出了展望。