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71.
Environmental impacts of water use in global crop production: hotspots and trade-offs with land use 总被引:1,自引:0,他引:1
Global crop production is causing pressure on water and land resources in many places. In addition to local resource management, the related environmental impacts of commodities traded along international supply chains need to be considered and managed accordingly. For this purpose, we calculate the specific water consumption and land use for the production of 160 crops and crop groups, covering most harvested mass on global cropland. We quantify indicators for land and water scarcity with high geospatial resolution. This facilitates spatially explicit crop-specific resource management and regionalized life cycle assessment of processed products. The vast cultivation of irrigated wheat, rice, cotton, maize, and sugar cane, which are major sources of food, bioenergy, and fiber, drives worldwide water scarcity. According to globally averaged production, substituting biofuel for crude oil would have a lower impact on water resources than substituting cotton for polyester. For some crops, water scarcity impacts are inversely related to land resource stress, illustrating that water consumption is often at odds with land use. On global average, maize performs better than rice and wheat in the combined land/water assessment. High spatial variability of water and land use related impacts underlines the importance of appropriate site selection for agricultural activities. 相似文献
72.
Recently, we introduced a novel approach for protein quantification based on isobaric peptide termini labeling (IPTL). In IPTL, both peptide termini are dervatized in two separate chemical reactions with complementary isotopically labeled reagents to generate isobaric peptide pairs. Here, we describe a novel procedure for the two chemical reactions to enable a cost-effective and rapid method. We established a selective N-terminal peptide modification reaction using succinic anhydride. Dimethylation was used as second chemical reaction to derivatize lysine residues. Both reactions can be performed within 15 min in one pot, and micropurification of the peptides between the two reactions was not necessary. For data analysis, we developed the force-find algorithm in IsobariQ which searches for corresponding peaks to build up peak pairs in tandem mass spectrometry (MS/MS) spectra where Mascot could not identify opposite sequences. Utilizing force-find, the number of quantified proteins was improved by more than 50% in comparison to the standard data analysis in IsobariQ. This was applied to compare the proteome of HeLa cells incubated with S-trityl-L-cysteine (STLC) to induce mitotic arrest and apoptosis. More than 50 proteins were found to be quantitatively changed, and most of them were previously reported in other proteome analyses of apoptotic cells. Furthermore, we showed that the two complementary isotopic labels coelute during liquid chromatography (LC) separation and that the linearity of relative IPTL quantification is not affected by a complex protein background. Combining the optimized reactions for IPTL with the open source data analysis software IsobariQ including force-find, we present a straightforward and rapid approach for quantitative proteomics. 相似文献
73.
A parallel-flow H(2)O(liquid)-H(2)O(vapor) equilibration and laser spectroscopy method provides a new way to monitor the hydrogen and oxygen stable isotopic composition of water from rivers or lakes or in hydrologic tracer tests in real time. Two custom-built equilibrator devices and one commercial membrane device were tested to determine if they could be used to convert natural water samples (lakes, rivers, groundwater) to a H(2)O gas phase for continuous online δ(18)O and δD isotopic analysis by laser spectroscopy. Both the commercial minimodule device and the marble-filled equilibrator produced water vapor in isotopic equilibrium with the flowing liquid water, suggesting that unattended field measurement using these devices is possible. Oxygen isotope disequilibrium was indicated using the minimodule device at low temperatures. 相似文献
74.
Hennig R. Trendelenburg Kollmann M. Lüdtke O. Kratky Zimmermann Zycha G. Becker H. W. Nolte v. Pohl Egner Glatzel Graf Schulz Müller Erich A. v. Wacek Sarten Frey-Wyssling af Ekenstam K. Storch A. Koehler Gumz B. Thunell Munds Keylwerth S. Nickel Gottwald Friedrich Seebach Fritz L. Metz A. Kraus Lechner Schaile Fessel Willy Kinberg Thiele Kraemer Schlüter Wenhart Troche Kaiser Seitz Krug 《Holz als Roh- und Werkstoff》1940,3(7-8):252-269
Ohne Zusammenfassung 相似文献
75.
Miriam Thomalla Andreas Schmid Julia Hehner Sebastian Koehler Elena Neumann Ulf Müller-Ladner Andreas Schffler Thomas Karrasch 《International journal of molecular sciences》2022,23(15)
Endosome-localized Toll-like receptors (TLRs) 3 and 9 are expressed and functionally active in adipocytes. The functionality and role of TLR7 in adipocyte biology and innate immunity of adipose tissue (AT) is poorly characterized. We analyzed TLR7 mRNA and protein expression in murine 3T3-L1 and primary adipocytes, in co-cultures of 3T3-L1 adipocytes with murine J774A.1 monocytes and in human AT. The effects of TLR7 agonists imiquimod (IMQ) and cell-free nucleic acids (cfDNA) on adipokine concentration in cell-culture supernatants and gene expression profile were investigated. We found that TLR7 expression is strongly induced during adipocyte differentiation. TLR7 gene expression in adipocytes and AT stroma-vascular cells (SVC) seems to be independent of TLR9. IMQ downregulates resistin concentration in adipocyte cell-culture supernatants and modulates gene expression of glucose transporter Glut4. Adipocyte-derived cfDNA reduces adiponectin and resistin in cell-culture supernatants and potentially inhibits Glut4 gene expression. The responsiveness of 3T3-L1 adipocytes to imiquimod is preserved in co-culture with J774A.1 monocytes. Obesity-related, adipocyte-derived cfDNA engages adipocytic pattern recognition receptors (PRRs), modulating AT immune and metabolic homeostasis during adipose inflammation. 相似文献
76.
Certain tasks undertaken by groups using Group Decision Support Systems (GDSS) can be viewed as search problems. These tasks involve arriving at a solution or decision where the problem is complex enough to warrant the use of computerized decision support tools. For these types of GDSS tasks, we propose to model the information exchange and convergence toward a solution by the group as a simple genetic algorithm. The simple genetic algorithm is a generalized search technique that is based on the principles of evolution and natural selection. Simply put, the best points in the current population are more likely to be selected and combined through genetic operators to determine new points. We propose that groups using GDSS to address certain tasks behave like a simple genetic algorithm in the manner in which possible solutions are generated, enhanced and altered in attempting to reach a decision or consensus. 相似文献
77.
78.
W. A. Koehler 《Journal of the American Ceramic Society》1930,13(3):57-60
Most of the usual types of whiteware are manufactured in West Virginia by 24 different firms. Data are given on the kinds of body raw materials used, and their geographic sources; the materials used for glazes; lawn meshes used; number and kinds periodic bisque kilns and glost kilns; number of car tunnel bisque and glost kilns; horns kilns are on fire and the cones reached in each of the various types of whiteware. 相似文献
79.
Chwen-Jen Shieh Casimir C. Akoh Philip E. Koehler 《Journal of the American Oil Chemists' Society》1996,73(4):455-460
The physical properties of sucrose polyester (SPE), prepared from different composite blends of fatty acid methyl esters (FAME)
of safflower oil, palm oil, and peanut oil, were evaluated by mixture response surface methodology. Optimum combinations of
fatty, acids to achieve specific physical properties of SPE were determined. The SPE most similar in physical properties to
peanut oil was obtained with a 55:45 molar ratio of mixed FAME from safflower oil and peanut oil. The physical properties
of SPE were significantly affected by the degree of saturation and the average chainlength of their composite fatty acids. 相似文献
80.
A proof of the Vose-Liepins conjecture 总被引:1,自引:0,他引:1
Gary J. Koehler 《Annals of Mathematics and Artificial Intelligence》1994,10(4):409-422
A key result sufficient for the asymptotic stability of the mixing operator in infinite population genetic algorithms depended upon a conjecture. While empirical results supported the conjecture, no proof has been heretofore obtained. In this paper we supply a proof of the conjecture. In so doing, we obtain properties useful for the study of genetic algorithms. 相似文献