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141.
While science advances technology, it is also true that technology advances science. Thus, the two bodies of knowledge are increasingly recognized as interdependent. Nonetheless, recent advances in information communication technology (ICT), in particular, may have profound implications for the norms by which science is conducted. For example, treatment of data will increasingly be in terms of probability distributions, rather than as point estimates, because the cost of computation is now so low that more robust approaches to treatment of uncertainty are within the grasp of normal science. Perhaps more importantly, the techniques by which scientists collaborate, communicate, and curate science are undergoing a rare period of rapid change. The papers in this special section exemplify the evolution of the relationship between technology and science in these two important ways: (1) treatment of data uncertainties and (2) participation in novel methods of publication and review. The latter was fostered by the 2016 meeting of the International Symposium on Sustainable Systems and Technologies (ISSST), at which all of the papers in this special section were presented. This editorial summarizes some of the trends in ICT that are the subject of experimentation in ISSST and introduces the idea that scientific societies in the information age are more likely to take the form of a network than they are likely to look like the societies of the last several centuries.  相似文献   
142.
A two-generation reproductive toxicity study of zinc chloride (ZnCl2) was conducted in rats. Fo male and female rats were administered 0.00 (control), 7.50 (low), 15.00 (mid) and 30.00 (high) mg/kg/day of ZnCl2. Selected F1 male and female rats were exposed to the same doses received by their parents (Fo). Exposure of F0 parental rats to ZnCl2 showed significant reduction in fertility, viability (days 0 and 4), and the body weight of F1 pups from the high-dose group but caused no effects on litter size, weaning index, and sex ratio. Similarly, the continued exposure of F1 parental rats to ZnCl2 also reduced fertility, liter size, viability (day 0), and the body weight of F2 pups within the high-dose group but caused no effects on weaning index and sex ratio. Exposure of ZnCl2 to F0 and F1 parental males resulted in a significant reduction in their body weights, and the F0 and F1 parental females did not show any significant difference in their body weights compared to their control groups. However, the postpartum dam weights of both F0 and F1 female rats were significantly reduced compared to their controls. Exposure of ZnCl2 to Fo and F1 generation parental rats did not produce any significant change of their clinical signs as well as their clinical pathology parameters, except the alkaline phosphotase (ALK) level, which showed an upward trend in both sexes of both generations. Exposure of ZnCl2 to F0 rats resulted in a reduction of brain, liver, kidney, spleen and seminal vesicles weights of males and in the spleen and uterus of females. Similarly, exposure of F1 rats to ZnCl2 also resulted in reduction of brain, liver, kidney, adrenal, spleen, prostate and seminal vesicles weights of males and in spleen and uterus of females. ZnCl2 exposure resulted in grossly observed gastro-intestianla (GI) tract, lymphoreticular/hematopoietic, and reproductive tract lesions in parental rats in both generations. Reduced body fat was also recorded in F1 parental rats.  相似文献   
143.
144.
Because wicked problems are beyond the scope of normal, industrial-age engineering science, sustainability problems will require reform of current engineering science and technology practices. We assert that, while pluralism concerning use of the term sustainability is likely to persist, universities should continue to cultivate research and education programs specifically devoted to sustainable engineering science, an enterprise that is formally demarcated from business-as-usual and systems optimization approaches. Advancing sustainable engineering science requires a shift in orientation away from reductionism and intellectual specialization towards integrative approaches to science, education, and technology that: (1) draw upon an ethical awareness that extends beyond the usual bounds of professional ethics or responsible conduct of research to include macroethics, (2) adopt anticipatory and adaptive approaches to unintended consequences resulting from technological innovation that result in more resilient systems, and (3) cultivate interactional expertise to facilitate cross-disciplinary exchange. Unfortunately, existing education and research training programs are ill-equipped to prepare scientists and engineers to operate effectively in a wicked problems milieu. Therefore, it is essential to create new programs of graduate education that will train scientists and engineers to become sustainable engineering science experts equipped to recognize and grapple with the macro-ethical, adaptive, and cross-disciplinary challenges embedded in their technical research and development programs.  相似文献   
145.
Stabilizing global greenhouse gas concentrations at levels to avoid significant climate risks will require massive "decarbonization" of all the major economies over the next few decades, in addition to the reduced emissions from other GHGs and carbon sequestration. Achieving the necessary scale of emissions reductions will require a multifaceted policy effort to support a broad array of technological and behavioral changes. Change on this scale will require sound, well-thought-out strategies. In this article, we outline some core principles, drawn from recent social science research, for guiding the design of clean technology policies, with a focus on energy. The market should be encouraged to make good choices: pricing carbon emissions and other environmental damage, removing distorting subsidies and barriers to competition, and supporting RD&D broadly. More specific policies are required to address particular market failures and barriers. For those technologies identified as being particularly desirable, some narrower RD&D policies are available.  相似文献   
146.
Organic solvents, such as dimethylsulfoxide (DMSO) and methanol are widely used as vehicles to solubilise lipophilic test compounds in toxicity testing. However, the effects of such solvents upon innate detoxification processes in aquatic organisms are poorly understood. This study assessed the effect of solvent exposure upon cytochrome P450 (CYP)-mediated xenobiotic metabolism in Daphnia magna and zebrafish larvae (4 d post fertilisation). Adult D. magna were demonstrated to have a low, but detectable, metabolism of ethoxyresorufin in vivo and this activity was not modulated by pre-exposure to DMSO or methanol (24 h, up to 0.1% and 0.05% v/v, respectively). In contrast, the metabolism of ethoxyresorufin in zebrafish larvae was significantly reduced by both solvents (0.1% and 0.05% v/v, respectively) after 24 h of exposure. In zebrafish, these observed decreases in activity towards ethoxyresorufin were accompanied by decreased expression of a variety of genes coding for drug metabolising enzymes (corresponding to CYP1, CYP2, CYP3 and UDP-glucuronyl transferase [UGT] family enzymes), measured by quantitative PCR. Reduction of gene expression and CYP1 enzyme activities by methanol (0.05% v/v) in zebrafish larvae was partially reversed by co-exposure with Aroclor 1254 (100 μg L−1). Overall this study suggests that relatively low concentrations of organic solvents can impact upon the biotransformation of certain xenobiotics in zebrafish larvae, and that this warrants consideration when assessing compounds for metabolism and toxicity in this species.  相似文献   
147.
Some plants are known as indoor air purifiers. A large number of studies report kinetic purification results for an extensive panel of plants, i.e. the pollutant concentration (volatile organic compounds, as known as VOC, most of the time) is continuously monitored by gas chromatography. However, only a few papers describe the mechanisms involved in such processes. This study deals with the use of secondary ion mass spectrometry imaging as an efficient tool to locate atmospheric pollutant as bromotoluene within the Hedera helix plant (leaf, roots) and the substrate on which it was previously grown. Hedera helix plants have been placed in a pollution chamber with control of the exposure parameters. Plant and soil samples excised were transferred into a fixative solution of glutaraldehyde and paraformaldehyde for a few days, were dehydrated using ethanol and were embedded with resin. Cross sections were made from the pale brown solids obtained. Then, a device using a cathodic pulverization device capable of depositing a few nanometers of gold atoms over the sample was used to make the surface electronically conductive for the NanoSIMS. Hence, polluted and unpolluted samples of Hedera helix and substrates were obtained following a careful procedure that allowed for the discrimination between polluted and nonpolluted ones. Nanoscale spatial resolution was an invaluable tool (NanoSIMS) to achieve this, and proved that VOCs, such as bromotoluene, were actually trapped by plants such as Hedera helix.  相似文献   
148.
1,4‐Dioxane (14DX) is classified as a probable human carcinogen by the US Environmental Protection Agency (EPA), and it has toxic effects on the kidney and liver. EPA's Health Advisory Level (HAL) for 14DX is 0.35 micrograms per liter (μg/L). Accordingly, several states have lowered their drinking water advisory levels and site cleanup levels. The widespread occurrence of 14DX in contaminated groundwater has contributed to a growing demand for remediation services. Treating 14DX is a challenge due to its very low Henry's law constant, low sorption potential, and strong ether linkages. The primary solution for 14DX remediation has been various forms of advanced oxidation processes (AOP), namely pump and treat followed by ex situ treatment with catalyzed ultraviolet light oxidation or ozone‐peroxidation. Many of the available advanced oxidation systems are complex, requiring careful monitoring and maintenance to adjust for variable source water and operating conditions. Synthetic media is a relatively new 14DX treatment technology that overcomes many of the operating challenges faced by existing technologies. AMBERSORB? 560 (AMBERSORB) has recently demonstrated the effective removal of 14DX over a wide range of concentrations and operating conditions, including those created by in situ thermal remediation. Consistent and reliable treatment down to sub‐0.3 μg/L levels differentiates synthetic media technology from other 14DX treatment technologies. AMBERSORB provides a solution to the problem of “stranded capital” by offering a 14DX treatment system capable of meeting regulatory standards today and in the foreseeable future. © 2014 Wiley Periodicals, Inc.  相似文献   
149.
Residues of pesticides in fish farming productions from barrage ponds are seldom studied in spite of increasing health questionings and environmental concerns. The purpose of this study is to establish the pesticide contamination profiles of sediments and edible fish from five ponds in Northeastern France. Multi-residues method and liquid chromatography–tandem mass spectrometry analysis were used to quantify 13 pesticides (azoxystrobin, carbendazim, clomazone, diflufenican, dimethachlor, fluroxypyr, iprodion, isoproturon, mesosulfuron-methyl, metazachlor, napropamid, quizalofop and thifensulfuron-methyl). Ten sediments and 143 muscles samples were analysed, corresponding to two successive fishing campaigns (first fishing date and second fishing date (P2), about 1 year later) on five sites (noted C-0, C-25, C-45, C-75 and C-85 to express the increasing gradient of crop area). Isoproturon was present in all sediments samples (1.8–56.4 μg/kg dry weight). During P2 period, carbendazim was quantified in the fish of site C-0 (0.09?±?0.02, 0.2?±?0.1 and 0.17?±?0.06 μg/kg wet weight (ww) for roach, carp and perch, respectively). Metazachlor was only quantified in perch of the site C-25 (0.13?±?0.02 μg/kg ww). Concentrations of isoproturon were similar for the sites C-45 and C-75 with 0.4?±?0.1 and 0.75?±?0.06 μg/kg ww for carp and perch, respectively. Contamination of fish reflected generally concentrations in surroundings. Isoproturon was the most concentrated and its main source was water for perch while carp was exposed through both water and sediments, highlighting their life strategies in pond.  相似文献   
150.
Intensive agricultural land use imposes multiple pressures on streams. More specifically, the loading of streams with nutrient-enriched soil from surrounding crop fields may deteriorate the sediment quality. The current study aimed to find out whether stream restoration may be an effective tool to improve the sediment quality of agricultural headwater streams. We compared nine stream reaches representing different morphological types (forested meandering reaches vs. deforested channelized reaches) regarding sediment structure, sedimentary nutrient and organic matter concentrations, and benthic microbial respiration. Main differences among reach types were found in grain sizes. Meandering reaches featured larger mean grain sizes (50–70 μm) and a thicker oxygenated surface layer (8 cm) than channelized reaches (40 μm, 5 cm). Total phosphorous amounted for up to 1,500 μg?g?1 DW at retentive channelized reaches and 850–1,050 μg?g?1 DW at the others. While N-NH4 accumulated in the sediments (60–180 μg?g?1 DW), N-NO3 concentrations were generally low (2–5 μg?g?1 DW). Benthic respiration was high at all sites (10–20 g O2 m?2?day?1). Our study shows that both hydromorphology and bank vegetation may influence the sediment quality of agricultural streams, though effects are often small and spatially restricted. To increase the efficiency of stream restoration in agricultural landscapes, nutrient and sediment delivery to stream channels need to be minimized by mitigating soil erosion in the catchment.  相似文献   
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