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991.
这个花园展现了需要保护的未来花园——海底花园深藏不露的美。莎拉·弗克说:"通过这个项目,我尝试着讲述大海的故事,一个可能会被后代遗忘的故事。大海是今天地球生命赖以生存的要素。大海产生了地球大气层中的大部分氧气,它吸入大气层的二氧化碳(CO2),它容纳了数百万种生物,其中有的生物构成了我们不可或缺的食物链。"  相似文献   
992.
Analysis of press reports of the onset of drought in Sydney in 2002 and London in 2006 shows different understandings of the relationship between infrastructure provision, individual behaviour and the environment. Drought is both a natural and cultural phenomenon requiring urban water managers to consider social as well as technical considerations in preparing for future droughts.  相似文献   
993.
994.
In 1994 an unusual, if not unique, collaborative effort emerged to manage the highly contested and interconnected system of waters, levees, and habitat in the San Francisco Bay Estuary and Sacramento-San Joaquin Delta. This CALFED Bay-Delta Program (CALFED) engaged 25 federal and state agencies and representatives of 35 major stakeholder groups and local agencies in a joint search for solutions to Bay Delta problems. It changed how water was managed and produced new practices that persisted until at least 2005. CALFED's collaborative approach is by nature informal, and it coexists uneasily with the norms and structure of formal government. This story illustrates how formal and informal systems are interdependent, yet in tension, across planning, participation, and decision making. Because planners often operate in the interface between the formal and the informal, the story offers lessons that can be applied at many levels of government and for many planning tasks.  相似文献   
995.
In smoking-induced chronic obstructive pulmonary disease (COPD), various comorbidities are linked to systemic inflammation and infection-induced exacerbations. The underlying mechanisms are unclear but might provide therapeutic targets. T-cell activity is central in systemic inflammation and for infection-defense mechanisms and might be influenced by comorbidities. Hypothesis: Circulating biomarkers of comorbidities modulate the activity of T-cells of the T-helper type 1 (Th1) and/or T-cytotoxic type 1 (Tc1). T-cells in peripheral blood mononuclear cells (PBMCs) from non-smokers (NS), current smokers without COPD (S), and COPD subjects (total n = 34) were ex vivo activated towards Th1/Tc1 and were then stimulated with biomarkers for metabolic and/or cardiovascular comorbidities (Brain Natriuretic Peptide, BNP; chemokine (C-C motif) ligand 18, CCL18; C-X3-C motif chemokine ligand 1, CX3CL1; interleukin-18, IL-18) or for asthma- and/or cancer-related comorbidities (CCL22; epidermal growth factor, EGF; IL-17; periostin) each at 10 or 50 ng/mL. The Th1/Tc1 activation markers interferon-γ (IFNγ), tumor necrosis factor-α (TNFα), and granulocyte-macrophage colony-stimulating factor (GM-CSF) were analyzed in culture supernatants by Enzyme-Linked Immunosorbent Assay (ELISA). Ex-vivo activation induced IFNγ and TNFα without differences between the groups but GM-CSF more in S vs. NS. At 10 ng/mL, the different biomarkers increased or reduced the T-cell activation markers without a clear trend for one direction in the different categories of comorbidities or for the different T-cell activation markers. At 50 ng/mL, there was a clear shift towards suppressive effects, particularly for the asthma— and cancer-related biomarkers and in cells of S and COPD. Comorbidities might suppress T-cell immunity in COPD. This could explain the association of comorbidities with frequent exacerbations.  相似文献   
996.
Bacteriocin production by Enterococcus faecium RZS C5 occurs in a growth-associated way but is generally switched off in the very early growth phase. The influence of environmental stress on the bacteriocin production kinetics by E. faecium RZS C5 was analysed at a controlled temperature of 35 degrees C and constant pH 6.5. The effect of environmental stress on bacteriocin production was depending on the type of stress applied. Oxidative stress did not interfere with cell growth or bacteriocin activity. In contrast, salt stress decreased both the cell growth and the specific bacteriocin production. Nevertheless, moderate levels of sodium chloride improved bacteriocin activity because they increased the biomass concentration at which bacteriocin production was switched off. Environmental stress due to limitations in sugar or complex nutrients did not affect the early shut-off mechanism or the specific bacteriocin production. However, bacteriocin stability decreased or increased at low levels of sugar or complex nutrients, respectively.  相似文献   
997.
In Bangladesh, homestead pond aquaculture currently comprises a polyculture of large fish species but provides an ideal environment to integrate a range of small fish species. Small fish consumed whole, with bones, head and eyes, are rich in micronutrients and are an integral part of diets, particularly for the poor. Results from three large projects demonstrate that the small fish, mola (Amblypharyngodon mola) contributes significantly to the micronutrients produced from all fish, in homestead ponds, in one production cycle. Mola contributed 98%, 56% and 35% of the total vitamin A, iron and zinc produced, respectively, despite comprising only 15% of the total fish production by weight. If consumed within the household, mola could contribute half of the vitamin A and a quarter of the iron intake recommended for a family of four, annually. Homestead ponds are uniquely accessible to women who prepare the household food. Further dissemination of the carp-small fish technology provides opportunities to target women and men together for training on fish production and consumption, nutrition and gender equity. Women only training is also recommended to enable them to engage fully, without feeling dominated by men. Partnering with the fisheries and health sectors will encourage sustainable uptake of this promising technology. Clearly, dissemination could have significant health benefits; however, improved monitoring and evaluation, particularly of dietary diversity and diet quality are essential. Research priorities should also include the production techniques of other small indigenous fish species (SIS), besides mola, and the power dynamics between women and men in operating homestead ponds.  相似文献   
998.
999.
The enzymes glucose oxidase and transglutaminase are frequently used to improve the breadmaking performance of wheat flours, as they have the ability to considerably alter the viscoelastic nature of the gluten network. To evaluate a flour’s breadmaking performance, rheological tests offer an attractive framework. In this study, the rheological impact of adding glucose oxidase or transglutaminase to wheat flour dough is investigated by means of linear oscillatory shear tests, creep-recovery shear tests and startup extensional tests. The former tests reveal that the enzymes render the dough stiffer and enhance its elastic character, until saturation is reached. In the breadmaking process, the use of excessive amounts of enzyme is known to be counterproductive. The strain-hardening index clearly reveals this overcross-linking effect. Besides enzymes, the gluten network can also be reinforced by adding supplementary gluten, which was indeed found to enhance the extent of strain-hardening.  相似文献   
1000.
Emissions from gasoline and diesel engines vary on time scales including diurnal, weekly, and decadal. Temporal patterns differ for these two engine types that are used predominantly for passenger travel and goods movement, respectively. Rapid growth in diesel fuel use and decreasing NOx emission rates from gasoline engines have led to altered emission profiles. During the 1990s, on-road use of diesel fuel grew 3 times faster than gasoline. Over the same time period, the NOx emission rate from gasoline engines in California was reduced by a factor of approximately 2, while the NOx emission rate from diesel engines decreased only slightly. Diesel engines therefore grew in both relative and absolute terms as a source of NOx, accounting for about half of all on-road NO, emissions as of 2000. Diesel truck emissions decrease by 60-80% on weekends. Counterintuitive responses to these emission changes are seen in measured concentrations of ozone. In contrast, elemental carbon (EC) concentrations decrease on weekends as expected. Weekly and diurnal patterns in diesel truck activity contribute to variability in the ratio of organic carbon (OC) to EC in primary source emissions, and this could be a source of bias in assessments of the importance of secondary organic aerosol.  相似文献   
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