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91.
Three-dimensional structure of the E. coli DNA-binding protein FIS 总被引:27,自引:0,他引:27
D Kostrewa J Granzin C Koch H W Choe S Raghunathan W Wolf J Labahn R Kahmann W Saenger 《Nature》1991,349(6305):178-180
92.
Susan Wolf 《Foundations of Science》2016,21(2):279-282
Responding to comments by Cheshire Calhoun and Arnold Burms, this piece clarifies some of Wolf’s ideas about the relation between meaningfulness in life, on the one hand, and reasons of love, fulfillment, and objective value, on the other. Meaning tends to come from activities whose reasons are grounded in love of a worthy (objectively valuable) object, and not necessarily from reasons having anything to do with an interest in meaningfulness itself. But what counts as a worthy object cannot be determined either from a totally neutral and impersonal point of view or from the points of view of specific other people who matter to the subject. 相似文献
93.
Marcos Leandro Hoffmann Souza Luis Henrique Rodrigues Maria Isabel Wolf Motta Morandi 《Systemic Practice and Action Research》2018,31(1):87-104
The growth of the petrochemical industry is based on end-user applications such as the automotive and construction sectors, which are the main drivers of the styrene market. However, the use of substitutes for petrochemicals is a reality and creates a competition in the applications of petroleum products. In this sense, this research aimed to design a system dynamics model to evaluate different scenarios, observing the behavior of the styrene demand over time. In the first phase of the project, a greater understanding of the issue was created and a closed loops diagram was elaborated. It was used during the second phase to design an explanatory regression validation model for the styrene demand. In phase three, a visualizing model and scenarios were designed. The scenarios themselves and the results of each scenario were evaluated. The designed and simulated scenarios aimed to evaluate the impact that the use of substitute materials and the variations in gross domestic product cause to the styrene market. The use of system dynamics together with scenario planning was efficient as different strategies for the market could be evaluated based on the simulated scenarios. A critical analysis of the model’s contribution to the decision-making within organizations concludes the study. 相似文献
94.
95.
Reductionism, in the sense of the doctrine that theories on different levels of reality should exhibit strict and general
relations of deducibility, faces well-known difficulties. Nevertheless, the idea that deeper layers of reality are responsible
for what happens at higher levels is well-entrenched in scientific practice. We argue that the intuition behind this idea
is adequately captured by the notion of supervenience: the physical state of the fundamental physical layers fixes the states
of the higher levels. Supervenience is weaker than traditional reductionism, but it is not a metaphysical doctrine: one can
empirically support the existence of a supervenience relation by exhibiting concrete relations between the levels. Much actual
scientific research is directed towards finding such inter-level relations. It seems to be quite generally held that the importance
of such relations between different levels is that they are explanatory and give understanding: deeper levels provide deeper
understanding, and this justifies the search for ever deeper levels. We shall argue, however, that although achieving understanding
is an important aim of science, its correct analysis is not in terms of relations between higher and lower levels. Connections
with deeper layers of reality do not generally provide for deeper understanding. Accordingly, the motivation for seeking deeper
levels of reality does not come from the desire to find deeper understanding of phenomena, but should be seen as a consequence
of the goal to formulate ever better, in the sense of more accurate and more-encompassing, empirical theories.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
96.
Dennis D. Austin 《西北部美国博物学家》2011,60(2)
History and technical literature describing potential effects of livestock grazing on mule deer ( Odocoileus hemionus ) populations and winter range habitat are reviewed. Recommendations for livestock grazing on winter ranges within the Great Basin are advanced. 相似文献
97.
Dennis D. Austin Robert A. Riggs Philip J. Urness David L. Turner John F. Kimball 《西北部美国博物学家》2011,49(1)
Trends in age-specific, eviscerated carcass weights were determined for hunter-harvested yearling and two-year-old buck mule deer. Carcass weights declined over an 11-year period from two areas of similar management, but with independenly collected data sets. Carcass weights also declined between the opening and second weekends of the hunt. Management implications are discussed. 相似文献
98.
Tame mule deer and elk were fed fresh alfalfa hay at night and given various alternate forages during the day. This schedule, simulating farmland depredation feeding, yielded consumption values for field-growing alfalfa hay. 相似文献
99.
During the summers of 1982, 1983, and 1984, 269 sheep dogs from an area endemic for hydatid disease were examined for cestodes ( Echinococcus granulosus and Taenia spp.). Each dog was given an oral purge of arecoline hydrobromide and then following purgation received a subcutaneous injection of praziquantel (Droncit ® ). During the three-year study period, 205 dogs were examined one time only, 48 dogs were examined two of the three years, and 16 dogs were examined each of the three years (= 349 separate examinations). In 1982, 45 of 91 dogs examined (49.5%) harbored at least one species of cestode. Those data for 1983 and 1984 were 55 positive of 141 examined (39.0%) and 34 positive of 117 examined (29.1%), respectively. The marked drop in dogs infected during the second and third year of the study suggests that many sheep ranchers were implementing some of the control measures recommended for prevention of E. granulosus infections. The numbers of separate purgations showing specific cestodes detected in all positive dogs (some dogs naturally with more than one species of cestode) were: E. granulosus, 16 (4.6%); T. hydatigena, 34 (9.7%); T. ovis krabbei, 46 (13.2%); T. pisiformis, 47 (13.5%); and T. serialis, 24 (6.9%). 相似文献
100.
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Diel activity and association patterns of white bass ( Morone chrysops ) and carp ( Cyprinus carpio ) in Utah Lake, Utah, were studied over four 24-hr periods during August 1980. Fish were concurrently sampled from two adjacent littoral habitats. Significant differences existed in diel activity patterns in two of three size classes of white bass and in diel association patterns of white bass and carp between the two habitat areas. Differences in habitat structure, and in biological activity between the habitat types, are implicated as the primary determinants of overall diel activity of fish in these littoral areas. 相似文献