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71.
72.
In this paper, we introduce Noosphere Networked Entry eXtension and Unification System (NNexus), a generalization of the automatic linking engine of Noosphere (at PlanetMath.org) and the first system that automates the process of linking disparate encyclopediardquo entries into a fully connected conceptual network. The main challenges of this problem space include: 1) linking quality (correctly identifying which terms to link and which entry to link to with minimal effort on the part of users), 2) efficiency and scalability, and 3) generalization to multiple knowledge bases and web-based information environment. We present the NNexus approach that utilizes subject classification and other metadata to address these challenges. We also present evaluation results demonstrating the effectiveness and efficiency of the approach and discuss ongoing and future directions of research.  相似文献   
73.
Organic field effect transistors have been fabricated on poly(ethylene terephthalate) film substrates with excellent operating characteristics and maximum mobilities of 1.1 cm2/(V s). The semiconductor was a solution processible blend of 6,13-bis(triisopropyl silylethynyl) pentacene and a poly(triaryl amine) used to combine the favourable properties of small molecules and polymers. We have demonstrated that such systems are a good candidate for flexible organic electronics and that the surface energy of the substrate plays a key role in controlling the morphology of the semiconductor film.  相似文献   
74.
It has previously been determined that (13S,9Z,11E)-13-hydroperoxy-9,11-octadecadienoic acid was mainly converted into (13S,9Z,11E)-13-hydroxy-9,11-octadecadienoic acid by 5 N KHO with preservation of the stereochemistry of the reactant [Simpson, T.D., and Gardner, H.W. (1993)Lipids 28, 325–330]. In addition, about 20–25% of the reactant was converted into several unknown by-products. In the present work it was confirmed that the stereochemistry was conserved during the hydroperoxy-diene to hydroxydiene transformation, but also, novel by-products were identified. It was found that after only 40 min reaction (9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid accumulated to as much as 7% of the total. Later, (9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid began to disappear, and several other compounds continued to increase in yield. Two of these compounds, 2-butyl-3,5-tetradecadienedioic acid and 2-butyl-4-hydroxy-5-tetradecenedioic acid, were shown to originate from (9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid, and they accumulated up to 2–3% each after 4 to 6 h. Some other lesser products included 11-hydroxy-9,12-heptadecadienoic acid, 3-hydroxy-4-tridecenedioic acid, 13-oxo-9,11-octadecadienoic acid and 12,13-epoxy-11-hydroxy-9-octadecenoic acid. Except for the latter two, most or all of the compounds could have originated from Favorskii rearrangement of the early product, (9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid, through a cyclopropanone intermediate.  相似文献   
75.
Iridoid glycosides were found to be sequestered by natural populations ofEuphydryas anicia after ingestion from the host plantsBesseya alpina, B. plantaginea, andCastilleja integra. Both major iridoids ofB. alpina, cataipol and aucubin, were found in butterfly populations where this was the only host plant. The catalpol-aucubin ratio was higher in the butterflies than in the host plant. AnE. anicia population which uses bothB. plantaginea andC. integra as host plants was found to sequester cataipol as well as another iridoid, macfadienoside. Macfadienoside was the major iridoid ofC. integra, while catalpol esters were the major iridoids ofB. plantaginea. Although it was a major sequestered iridoid, catalpol was a minor constituent in both host plants. The macfadienoside-catalpol ratio in the butterflies from this population was highly variable, and there appeared to be both sex and individual variation in host plant and/or iridoid glucoside utilization byE. anicia. Although other iridoids were present in the host plants, none was sequestered in more than trace amounts.This work was supported by grant CHE-8213714 to FRS, in part by grant DEB-06961 to PRE from the National Science Foundation, and a grant from the Koret Foundation of San Francisco to PRE. Paper 5 in the series Chemistry of the Scrophulariaceae. Paper 4: Roby, M.R. and Stermitz, F.R. 1984.J. Nat. Prod. 47:854–857.  相似文献   
76.
This communication reports the results of some exploratory experiments to examine the surface of coal by (i) flow microcalorimetry (FM) and (ii) vapour sorption calorimetry (VSC). Excepting differential scanning calorimetry, calorimetric methods have not been widely-exploited in coal structure research. The intent of this short communication is to demonstrate that hitherto neglected calorimetric methods are very rewarding when applied to the study of coal surfaces.  相似文献   
77.

This research investigated how people’s perceptions of alternative water sources compare with their perceptions of other technologies, and identified significant predictors of comfort with different alternative water sources. We drew on data from four questionnaire survey studies with a total sample of more than 1200 Australian participants. Relative levels of comfort with the alternative water sources was consistent across the four studies: comfort was always highest for drinking rainwater and lowest for drinking recycled water, with comfort with drinking treated stormwater and desalinated water sitting between these two. Although comfort with drinking recycled water was always lowest of the four alternative water sources, participants were significantly more comfortable with drinking recycled water than they were with nuclear energy, or with using genetically modified plants and animals for food. In general, demographic variables were less important predictors of comfort with alternative water sources than were psychological variables; only age and gender emerged as relatively consistent predictors for recycled water, stormwater, and desalinated water, with older participants and males more comfortable with drinking these water sources. Of the psychological variables, participants’ comfort with technology in general, trust in science and trust in government emerged consistently as significant positive predictors of comfort with drinking recycled water, stormwater, and desalinated water.

  相似文献   
78.
Many lotic fish species use natural patterns of variation in discharge and temperature as spawning cues, and these natural patterns are often altered by river regulation. The effects of spring discharge and water temperature variation on the spawning of shovelnose sturgeon Scaphirhynchus platorynchus have not been well documented. From 2006 through 2009, we had the opportunity to study the effects of experimental discharge levels on shovelnose sturgeon spawning in the lower Marias River, a regulated tributary to the Missouri River in Montana. In 2006, shovelnose sturgeon spawned in the Marias River in conjunction with the ascending, peak (134 m3/s) and descending portions of the spring hydrograph and water temperatures from 16 °C to 19 °C. In 2008, shovelnose sturgeon spawned in conjunction with the peak (118 m3/s) and descending portions of the spring hydrograph and during a prolonged period of increased discharge (28–39 m3/s), coupled with water temperatures from 11 °C to 23 °C in the lower Marias River. No evidence of shovelnose sturgeon spawning was documented in the lower Marias River in 2007 or 2009 when discharge remained low (14 and 20 m3/s) despite water temperatures suitable and optimal (12 °C?24 °C) for shovelnose sturgeon embryo development. A similar relationship between shovelnose sturgeon spawning and discharge was observed in the Teton River. These data suggest that discharge must reach a threshold level (28 m3/s) and should be coupled with water temperatures suitable (12 °C?24 °C) or optimal (16 °C?20 °C) for shovelnose sturgeon embryo development to provide a spawning cue for shovelnose sturgeon in the lower Marias River. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
79.
For more than half a century, in nearly all western states, the regulatory agencies (the State Engineer or equivalent) used impairment of other water rights as the primary criterion for approving or rejecting change applications to move water to higher-valued uses. In recent years, however, protests to change applications have been brought by 'stakeholders' who do not own water rights, but who argue that they are affected by water transfers. Under the impairment rule, these parties do not have statutory standing to protest successfully. But they have brought legal suits to block transfers, and the courts have considered whether additional criteria involving 'impacts on social welfare' are needed to evaluate transfers. State Supreme Court rulings on such suits in Utah and Nevada are reviewed as prototype cases. The Utah court held that additional 'social welfare' criteria must be utilized by the State Engineer in evaluating change applications, whereas the Nevada court held that such criteria were already incorporated in existing water statutes and administrative practice. The critical question raised in the paper is whether existing state regulatory agencies can effectively implement a real 'social welfare' criterion to evaluate change applications. The conclusion is that they probably cannot, and that if they try, water allocations will be politicized to a much greater extent than they are now, and efficient market transfers will be impeded if not completely prevented.  相似文献   
80.
A modified technique for vaso-vasostomy is described with the aim to achieve better results in operative recanalization and restoration of fertility after vasectomy. Vaso-vasostomy is a success when the man is able to produce fertile semen. Criteria for a fertile semen are mentioned. Fertile semen was obtained in all 5 patients treated by this modified technique.  相似文献   
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