鲨鱼皮微复制技术在抗菌防护领域中的应用研究

生物制造工程是在生命科学和仿生学基础上建立起来的前沿科技,通过基因复制、生物去除、生物生长、生物约束等方法将生物体特质直接复制到模具上,从而赋予产品特定的使用功能。本文通过对鲨鱼皮肤的分析论述了其抗菌机理以及利用生物约束成型技术将新鲜鲨鱼皮微结构复制到模具上的工艺流程。     

A dangerous bet: The challenges of formalizing artisanal mining in the Democratic Republic of Congo

Among policy-makers and governments, there is a broad consensus that artisanal and small-scale mining (ASM) needs to be ‘formalized’ – embodied in a standardized legal framework that is registered in and governed by a central state system-, the basic condition being that artisanal miners are given formal property rights. This article aims to contribute to this discussion, drawing on a case study from the Eastern Democratic Republic of Congo (DRC), where it is estimated that up to 90 percent of mineral production and export is ‘informal’. After having pointed out some of the theoretical assumptions behind the formalization canon, we study the challenges of formalizing the mining sector in the DRC. Next, we provide an in-depth analysis of one concrete policy measure of the Congolese government, the temporary ban on all artisanal activities. We argue that the mining ban was not only a radical example of a top-down formalization policy, but also an illustration of a bureaucratic and technical measure that compounds but does not address different problems associated with ASM: conflict, informality, poverty, illegality, state control. Looking at the empirical evidence from the DRC, we argue that these kinds of technical solutions can never address the broader socio-economic and political issues at stake.     

Microbial growth with vapor-phase substrate

Limited information exists on influences of the diffusive transport of volatile organic contaminants (VOC) on bacterial activity in the unsaturated zone of the terrestrial subsurface. Diffusion of VOC in the vapor-phase is much more efficient than in water and results in effective VOC transport and high bioavailability despite restricted mobility of bacteria in the vadose zone. Since many bacteria tend to accumulate at solid-water, solid-air and air-water interfaces, such phase boundaries are of a special interest for VOC-biodegradation. In an attempt to evaluate microbial activity toward air-borne substrates, this study investigated the spatio-temporal interplay between growth of Pseudomonas putida (NAH7) on vapor-phase naphthalene (NAPH) and its repercussion on vapor-phase NAPH concentrations. Our data demonstrate that growth rates of strain PpG7 were inversely correlated to the distance from the source of vapor-phase NAPH. Despite the high gas phase diffusivity of NAPH, microbial growth was absent at distances above 5 cm from the source when sufficient biomass was located in between. This indicates a high efficiency of suspended bacteria to acquire vapor-phase compounds and influence headspace concentration gradients at the centimeter-scale. It further suggests a crucial role of microorganisms as biofilters for gas-phase VOC emanating from contaminated groundwater or soil.     

Phosphine migration at the water-air interface in Lake Taihu, China

The diurnal atmospheric phosphine (PH₃) concentrations and fluxes at the water-air interface in Lake Taihu were reported. The results showed that the PH₃ flux at the water-air interface ranged from −69.9 ± 29.7 to 121 ± 42 ng m⁻² h⁻¹, with a mean flux of 14.4 ± 22.5 ng m⁻² h⁻¹. The fluxes were both negative and positive during the diurnal period, indicating that the lake can act as a sink and a source of PH₃. In addition, the PH₃ fluxes were positively correlated with water temperature, total soluble phosphorus and soluble reactive phosphorus, while they were negatively correlated with water redox potential. A similar diurnal variation curve of atmospheric PH₃ concentrations was observed during all four seasons, with the maximum level occurring in early morning and the minimum appearing around midday. These findings suggest that light plays an important role in the elimination of atmospheric PH₃. A significant positive correlation was also found between air temperature and atmospheric PH₃ concentration. The mean flux of PH₃ in Lake Taihu was higher than in other reported wetlands, with an estimated annual emission of PH₃ to the atmosphere of 2.94 × 10⁵ g y⁻¹.     

浅析“H31”类目在《中图法》（第五版）中的变化

逐一对比《中图法》第四版与第五版的H31（英语）类目,全面概括第五版《中图法》英语类目修改情况,并解读其修改重点,旨在帮助读者深入理解《中图法》第五版英语类目的分类变化,指导其实际运用。     

“Horizontal” and “vertical” diffusion: The cumulative influence of Impact and Benefit Agreements (IBAs) on mining policy-production in New Caledonia

The scale, duration and intensity of conflicts over mineral resources vary greatly. However, they always involve, in varying proportions, the triad stakeholder model—corporation, state, community—each element of which is internally heterogeneous. Increasingly, new players are entering the scene: international non-governmental organizations (NGOs), environmental grassroots groups, indigenous transnational networks, international aid and development agencies. Nevertheless, conflicts and arrangements around access to and control over mineral resources can take the apparent form of dyadic relationships between companies and local communities, resulting in negotiated company-community agreements, often called “Impact and Benefit Agreements” (IBAs). In our analysis, local agreements on mineral resource governance are seen as building blocks in the production of mining policy “from below”, even though they seem at first sight to exclude the state. This paper argues that these agreements, and the negotiations surrounding them, inform debates around mining through both “horizontal diffusion” (influence on other localities facing similar situations) and “vertical diffusion” (influence on policy design and implementation at upper political and administrative levels). This diffusion may occur in a “positive” sense, effecting further change in line with the intent of the original agreement, or in a “negative” one, actually making substantive change less likely, whether at a community or policy level. We build this argument through two case studies from New Caledonia, in the south-west Pacific, where mining has long been a key issue, especially in the current context of “negotiated decolonization” launched by the 1998 Nouméa Accord.     

论我国《海域使用管理法》的修订

《海域使用管理法》对中国海洋法制建设具有重要意义。该法施行以来,我国海域使用管理配套法规体系日趋完善,海洋功能区划、海域有偿使用等制度日臻成熟。《海域使用管理法》实施已逾15年,我国经济社会生活发生了巨大变化,中国特色社会主义法律体系不断完善,该法暴露出来的问题日益增多,亟待修订:首先,立法理念应由"重发展,轻保护"向"海域资源和海洋环境保护优先"变革。其次,应完善海域使用权制度,突出海域使用权的物权性,强化该法的私权色彩,将海域使用权的成立时间修改为"完成登记之日"。在围填海管理方面,应理顺围填海建设项目的审批程序,提高行政效率;建立填海造地指标管理制度。最后,在法律责任方面,应明确"恢复原状"的适用条件;修改罚款的计算方法,对于具有持续性的严重海域违法行为可以引入"按日处罚"制度;增加刑事责任条款;赋予海洋行政执法机构必要的行政强制手段。     

Oxidation reactivity of 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) by Compound I model of cytochrome P450s

Alternative brominated flame retardants (BFRs) have become prevalent as a consequence of restrictions on the use of polybrominated diphenyl ethers (PBDEs). For risk assessment of these alternatives, knowledge of their metabolism via cytochrome P450 enzymes is needed. We have previously proved that density functional theory (DFT) is able to predict the metabolism of PBDEs by revealing the molecular mechanisms. In the current study, the reactivity of 1,2-bis(2,4,6-tribromophenoxy)ethane and structurally similar chemicals with the Compound I model representing the active site of P450 enzymes was investigated. The DFT calculations delineated reaction pathways which lead to reasonable explanations for products that were detected by wet experiments, meanwhile intermediates which cannot be determined were also proposed. Results showed that alkyl hydrogen abstraction will lead to bis(2,4,6-tribromophenoxy)ethanol, which may undergo hydrolysis yielding 2,4,6-tribromophenol, a neurotoxic compound. In addition, a general pattern of oxidation reactivity regarding the 2,4,6-tribromophenyl moiety was observed among several model compounds. Our study has provided insights for convenient evaluation of the metabolism of other structurally similar BFRs.     

Hands-on assistance improves already successful pollution prevention services of the toxics use reduction institute’s laboratory

In an attempt to improve the adoption rate of the work conducted at the Toxics Use Reduction Institute Lab, a more comprehensive on-site follow-up assistance program was implemented in 2006. The effort was piloted for trichloroethylene replacement in Rhode Island in conjunction with Environmental Protection Agency (EPA) Region 1.Through hands-on workshops and on-site assistance efforts, the TURI Lab project was able to achieve an 82% reduction in TCE in a two year period. This new methodology for on-site assistance follow-up to the preexisting TURI Lab testing program has been incorporated into the work the Lab conducts for companies in Massachusetts. The Lab had an implementation rate of around 30% without on-site assistance. During the first year of the new process, the adoption rate has jumped to 80% of all companies working with the lab.     

实际污水培养好氧颗粒污泥及其特性研究

采用实际城市污水在序批式反应器(SBR)中试装置中成功培养出好氧颗粒污泥.颗粒污泥的沉降速率>21 m·h-1,显示了良好的沉降性能.颗粒污泥对化学需氧量(COD)、氮(N)、磷(P)具有同步去除的能力.在3 h的运行周期中,反应器出水COD<50 mg·L-1,氨氮(NH+4-N)<5.0 mg·L-1,总氮(TN)<15 mg·L-1,对TN和总磷(TP)的去除率达到50%.采用共聚焦激光扫描显微镜(CLSM)对好氧颗粒污泥的结构分析表明,好氧颗粒污泥的胞外多聚物(EPS)在整个颗粒污泥中均匀地分布,构成颗粒污泥的骨架.对颗粒污泥的X射线衍射(XRD)分析显示,在好氧颗粒污泥的内部存在许多无机矿物质,在颗粒污泥形成初期,废水中的无机成分可能具有"晶核"的作用.