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181.
Applicability of Adapted Reservoir Operation for Water Stress Mitigation Under Dry Year Conditions 总被引:3,自引:2,他引:1
Oliver Olsson Malika Ikramova Melanie Bauer Jochen Froebrich 《Water Resources Management》2010,24(2):277-297
This paper introduces the conjunctive use of a deterministic water quality model and water balance criteria for supporting
the assessment of simulation and to evaluate the effectiveness of proposed operation strategies. By this, the applicability
of enhanced reservoir operation strategies addressing both water quality as well as water quantity aspects under water deficit
conditions in dry years can be shown. Arguments will be developed to address stakeholders and decision makers in the context
of a more conservative past operation regime. Results are presented for the Kaparas reservoir, which is located in the lower
Amu Darya River, on the border of Turkmenistan and Uzbekistan. As being one out of four large reservoirs of the Tuyamuyun
Hydro Complex (THC), the Kaparas reservoir could be increasingly used for drinking water supply for the lower Amu Darya region.
The results for the dry year 2001 indicates that the combination of simulation together with practical assessment criteria
confirm the applicability of adapted operation rules for THC reservoirs and ways can be found to supply the local population
(of the lower Amu Darya region) with more potable water of higher quality even subject to a parallel reduction of water deficits.
Future aggravation of water stress due to increasing population growth and water quality deterioration will require a more
comprehensive consideration of water quality aspects in many arid and semi arid regions. The experience gained during this
study emphasizes the fact that classical deterministic water quality models provide effective tools to address even more complex
water quality problems under water stressed conditions, provided processing of results is performed, to support the decision
making process. 相似文献
182.
Brian Roark Russell Beckley Chris Gibbons Melanie Fried-Oken 《Computer Speech and Language》2013,27(6):1212-1234
Individuals with severe motor impairments commonly enter text using a single binary switch and symbol scanning methods. We present a new scanning method – Huffman scanning – which uses Huffman coding to select the symbols to highlight during scanning, thus minimizing the expected bits per symbol. With our method, the user can select the intended symbol even after switch activation errors. We describe two varieties of Huffman scanning – synchronous and asynchronous – and present experimental results, demonstrating speedups over row/column and linear scanning. 相似文献
183.
Thomas Wiegand Melanie Siedow Hellmut Eckert Gerald Kehr Gerhard Erker 《Israel journal of chemistry》2015,55(2):150-178
Frustrated Lewis pair (FLP) chemistry has provided a new strategy for small-molecule binding and/or catalytic activation. The most prominent FLPs are based on intramolecular phosphane borane adducts, the catalytic properties of which can be tailored over wide ranges of reactivity and selectivity. Advanced solid-state NMR spectroscopic techniques, together with DFT calculations, can provide new structural insights in these systems. This review illustrates the utility of 31P and 11B NMR chemical shifts, 11B electric field gradient tensors, and 31P 11B indirect and direct dipole dipole interactions for characterizing intramolecular borane phosphane FLPs. We demonstrate the potential of this method to 1) quantify the extent of boron phosphorus bonding interactions (and hence, the “degree of frustration”); 2) reveal specific structural details (i.e., boron phosphorus distances and other local geometric aspects) related to their catalytic activities; and (3) characterize products of FLP reactions with regard to molecular structure, stereochemistry, and aggregation properties in terms of internuclear distances, bonding connectivities, and orientational parameters. 相似文献
184.
Susanna M. Früh Philipp R. Spycher Dr. Maria Mitsi Melanie A. Burkhardt Prof. Dr. Viola Vogel Dr. Ingmar Schoen 《Chembiochem : a European journal of chemical biology》2014,15(10):1481-1486
A straightforward strategy is presented for the site‐specific incorporation of fluorophores or reactive probes into the extracellular matrix (ECM) protein fibronectin (Fn) by using the enzyme‐catalyzed transamidation by activated factor XIII. Characterization by SDS‐PAGE, western blotting, absorption measurements, mass spectrometry, and stepwise photobleaching for labeling quantification at the single‐molecule level showed that the labeling was efficient and restricted to the N‐terminal tails. The introduction of labels did not interfere with Fn fibrillogenesis, as verified by the incorporation of fluorescently labeled Fn into ECM and manually pulled Fn fibers. Site‐specific incorporation of an azide was used to create a template for bioorthogonal click chemistry reactions in a second bioconjugation step, thus offering versatile modification and application possibilities in the context of matrix biology and tissue engineering. 相似文献
185.
Melanie L. Mastronardi Eric J. Henderson Daniel P. Puzzo Geoffrey A. Ozin 《Advanced materials (Deerfield Beach, Fla.)》2012,24(43):5890-5898
Nanomaterials are becoming increasingly widespread in consumer technologies, but there is global concern about the toxicity of nanomaterials to humans and the environment as they move rapidly from the research laboratory to the market place. With this in mind, it makes sense to intensify the nanochemistry community's global research effort on the synthesis and study of nanoparticles that are purportedly “green”. One potentially green nanoparticle that seems to be a most promising candidate in this context is silicon, whose appealing optical, optoelectronic, photonic, and biomedical attributes are recently gaining much attention. In this paper, we outline some of our recent contributions to the development of the growing field of silicon nanocrystals (ncSi) in order to stress the importance of continued study of ncSi as a green alternative to the archetypal semiconductor nanocrystals like CdSe, InAs, and PbS. While a variety of developments in synthetic methods, characterization techniques, and applications have been reported in recent years, the ability to prepare colloidally‐stable monodisperse ncSi samples may prove to have the largest impact on the field, as it opens the door to study and access the tunable size‐dependent properties of ncSi. Here, we summarize our recent contributions in size‐separation methods to achieve monodisperse samples, the characterization of size‐dependant property trends, the development of ncSi applications, and their potential impact on the promising future of ncSi. 相似文献
186.
Objectives
To investigate the relationship between smoke‐free law coverage and secondhand smoke (SHS) exposure in the United States non‐smoking adult population.Design
We used data from the 1999–2002 National Health and Nutrition Examination Survey, a cross‐sectional survey designed to monitor the health and nutritional status of the US population. Serum cotinine levels were available for 5866 non‐smoking adults from 57 survey locations. Each location was categorised into one of three groups indicating extensive, limited, and no coverage by a smoke‐free law.Main outcome measures
The proportion of adults with SHS exposure, defined as having serum cotinine levels ⩾ 0.05 ng/ml.Results
Among non‐smoking adults living in counties with extensive smoke‐free law coverage, 12.5% were exposed to SHS, compared with 35.1% with limited coverage, and 45.9% with no law. Adjusting for confounders, men and women residing in counties with extensive coverage had 0.10 (95% confidence interval (CI) 0.06 to 0.16) and 0.19 (95% CI 0.11 to 0.34) times the odds of SHS exposure compared to those residing in counties without a smoke‐free law.Conclusions
These results support the scientific evidence suggesting that smoke‐free laws are an effective strategy for reducing SHS exposure. 相似文献187.
188.
Malvidin (mv) has been identified as a potential inhibitor of 3',5'-cyclic adenosine monophosphate (cAMP) phosphodiesterases (PDE). This study was to investigate if, as a possible consequence of intracellular PDE inhibition, the activity of the mitogen-activated protein kinase (MAPK) cascade is affected by mv treatment. At a concentration of 5 microM of mv a significant decrease of phosphorylated ERK1 and ERK2 (ERK, extracellular regulated kinase) in HT29 cells was observed. However, an increase in substance concentration led to a substantial recurrence of the phosphorylated enzymes. Cell cycle analysis underlined that indeed G(1)-relevant targets are only marginally affected by mv. The recurrence of phosphorylated ERK1/2 and the lack of effectiveness on the G(1)-passage up to 100 microM indicated that the inhibition of cAMP-specific PDEs is of minor relevance for the growth-inhibitory properties of mv in HT29 cells. In contrast, the release of cells, synchronised in the G(2)/M-phase of the cell cycle by nocodazole treatment, was effectively blocked in the presence of 1 microM mv. These results suggest that mv interferes with cellular targets relevant for G(2)/M-progression which have not been identified so far. 相似文献
189.
190.
Interactive narratives are stories that allow readers to determine the direction of the plot, often at key decision points. Unanswered questions remain about the types of psychological processes evoked by these “Choose Your Own Adventure” style narratives, as well as the relative persuasive influence of interactive narratives compared to traditional narratives. The current paper reviews the existing literature and provides a theoretical framework to guide future research on interactive narratives, particularly as a tool for entertainment‐education efforts. Specifically, we highlight increased user control and looser narrative structure as key elements of interactive narratives, and discuss possible effects of these differences on engagement variables (e.g., transportation, identification, perceived realism), self‐related variables (responsibility), and outcomes (e.g., enjoyment, attitude change, health behaviors). 相似文献