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991.
The Revised NEO Personality Inventory domains of Neuroticism and Agreeableness are considered factorially distinct despite several intercorrelations between these domains. The genetic correlation, an index of the degree to which these intercorrelations are caused by genetic influences, was estimated using data from 913 monozygotic and 562 dizygotic volunteer twin pairs from Canada, Germany, and Japan. The serotonin transporter gene, 5-HTTLPR, was assayed in a sample of 388 nontwin sibling pairs from the US to determine the contribution of the serotonin transporter locus to the covariation between the Neuroticism and Agreeableness scales. In all four samples, genetic influences contributed to the covariance of Neuroticism and Agreeableness, with the serotonin transporter gene accounting for 10% of the relationship between these domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
This study was designed to test how the sulfoalkyl ether (SAE) modification of beta-cyclodextrin (beta-CD) affects the binding capacity of testosterone and progesterone, thereby enhancing their solubility. The SAE-beta-CD derivatives contain either sulfopropyl ether (SPE) or sulfobutyl ether (SBE) groups on the 2-, 3-, and 6-hydroxyl positions of the dextrose moieties. SAE-beta-CDs are a mixture of positional and regional isomers containing from one to as many as 12 SAE groups per CD. The effect of chain length and the degree of substitution on complexation behavior was investigated by the phase-solubility method. The results were compared with those obtained with beta-CD, where possible, and with hydroxypropyl-beta-CD (HP-beta-CD). To determine the effect of degree of substitution (DS) on the binding, mixtures of SAE-beta-CDs with multiple substitution levels and varying average degrees of substitution were studied as well as mixtures of SAE-beta-CDs that contained the same degree of substitution. Mixtures that contained SAE-beta-CDs of the same degree of substitution were isolated from the multiple substitution level mixtures by ion-exchange chromatography and purified for investigation. Unlike the parent beta-CD, linear increases in the apparent solubilities of testosterone and progesterone were observed, and the binding potentials were comparable to those of beta-CD or better. The results demonstrate that the binding potentials of the SAE-beta-CD derivatives were dependent on the guest molecule, the degree of substitution, and the alkyl ether chain length. Our previous study showed the inhibition of complexation by direct sulfonation of the beta-CD. However, in the present work, interferences with the charged sulfonate groups were avoided by repositioning them away from the cavity. Increasing the degree of substitution assisted in complex formation; however, its effects were limited. Reduction of the alkyl chain length, as in the case of SPE-beta-CD compared with SBE-beta-CD, decreased the complexation potential. This decrease in complexation potential was further suppressed with an increase in the number of substituents placed on the CD torus. Generally, the binding potential of SAE-beta-CD derivatives increased with increasing alkyl chain length. However, placement of more than an optimum number of SAE groups on the CD torus resulted in inhibition of complexation.  相似文献   
993.
BACKGROUND: The treatment of osteoradionecrosis (ORN) and early chronic osteomyelitis (COM) of the mandible and maxilla is controversial. Hyperbaric oxygen (HBO) at two to three times the atmospheric pressure at sea level can result in tissue oxygen tension of almost 400 mmHg. Herewith HBO increases oxygen supply in hypoxic tissue, thus inducing fibroblastic proliferation and capillary formation. METHODS: From 1981 to 1991, we used a monoplace chamber and since 1992, we have also had a multiplace chamber for HBO treatment. Hyperbaric oxygen was given at 2.5-2.8 atmosphere absolute pressure (ATA) for 90-120 minutes, once per day. The patients had five to 10 preoperative and five to seven postoperative sessions. Surgical therapy consisted of decortication of the affected bone, subsequently covered with a free periosteal transplant from the tibia. RESULTS: Thirty-six patients with ORN and 33 with COM of the mandible and maxilla was treated with this protocol. The median follow-up time in this material is 34 months, with a minimum of 10 months. Thirty-six ORN patients (92%) and 26 COM patients (79%) have remained symptom-free after the first treatment period. Three failed ORN patients were successfully treated with a free microvascular flap. The seven failed COM patients have been retreated, and five of them have occasional clinical symptoms. CONCLUSIONS: Hyperbaric oxygen is a promising adjunct to surgery in the treatment of mandibular and maxillary ORN and COM. Using this protocol, the necessary HBO treatment sessions have been reduced from earlier protocols, without adverse effect on the outcome.  相似文献   
994.
The mechanisms involved in the initiation and the propagation of intercellular calcium signaling (calcium waves) were studied in cultured rat astrocytes. The analysis of calcium waves, induced either by mechanical stimulation or by focal application of ionomycin, indicated that initiation was dependent on the presence of external calcium. In addition, pharmacological experiments indicate that intercellular propagation required PLC activation, integrity of IP3-sensitive internal calcium stores, and functional gap junctions. An extracellular action of ATP or glutamate and participation of voltage-dependent Ca2+ channels were tested by using enzymatic degradation, receptor antagonists, and channel blockers, respectively. Because neither the speed of propagation nor the extent of the calcium waves was affected by these treatments, these alternate mechanisms were excluded from playing a role in intercellular calcium signaling. Biochemical assays and focal applications of several agonists (methoxamine, carbachol, glutamate) of membrane receptors to neurotransmitters and peptides (endothelin 1) demonstrated that their ability to trigger regenerative calcium waves depended on phospholipase C activity and inositol phosphate production. Thus, in rat astrocytes, initiation and propagation of calcium waves involve a sequence of intra- and intercellular steps in which phospholipase C, inositol trisphosphate, internal calcium stores, and gap junction channels play a critical role. The identification of these different events allows us to determine several targets at which the level of long-range signaling in astrocytes may be controlled.  相似文献   
995.
In 2 laboratory studies, 145 male and female undergraduates were selected for the role of manager either on the basis of merit or preferentially on the basis of their sex. Results of the 1st study indicate that when female Ss had been selected preferentially as compared with on a merit basis, they reacted more negatively to female (but not to male) applicants for an entry-level position in terms of personnel evaluations and competence ratings and they recommended female applicants for hire less frequently and less enthusiastically. No differences in personnel evaluations were found as a result of preferential selection when the Ss were male (Study 1) or when Ss were provided with favorable information about their ability (Study 2). Implications for implementation of affirmative action programs are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
996.
International society has begun to consider river basins and the coastal zone as one management unit that requires an ecosystem approach. Various countries have undertaken initiatives since the 1970s and have improved the approach to integrated coastal zone management. Brazil has not been one of them. Its sector-based approach to most environmental issues started in the 1980s with the National Environmental Policy Act (Law 6,938/1981). The National Coastal Zone Management Plan (NCZMP) was then approved by Law 7,661 in 1988. Shortly thereafter, the 1988 Brazilian Constitution was enacted, which established the environment as a common good to be used by the entire society but in such a way as to prevent environmental degradation and conserve its quality for present and future generations. The National Water Resources Policy (NWRP) was not enacted until 1997 (Law 9,433/1997). This law established that water resource management in Brazil must take into account estuarine ecosystems and the coastal zone, using an integrated approach. Only in 2006 did the National Water Resources Council (NWRC) create a technical chamber dedicated to developing regulatory measures for integrated management in Brazil. There has been substantial discussion and various proposals to implement it, as outlined in this article. This paper concludes with suggestions for implementing integrated river basin and coastal zone management in Brazil.  相似文献   
997.
BACKGROUND: The reasons for variations in the amount and size distribution of polymeric protein in mature wheat, related to bread‐making quality, are not fully understood and can be sought during the protein polymer formation period of grain maturation. The present study was aimed at investigating the accumulation and polymerisation of grain storage proteins during grain maturation and their relations to changes in falling number and grain water content in four cultivars of field‐grown winter wheat. RESULTS: Proteins were accumulated and polymerised similarly during grain development independently of cultivation environment, cultivar and fertiliser rate. A 3–6 day delay in maturity among cultivars led to a 3–12 day delay in protein accumulation during early grain development. An increase in nitrogen fertiliser rate from 160 to 200 kg N ha?1 resulted in a 20% increase in the amount of sodium dodecyl sulfate (SDS)‐unextractable protein. Precipitation just before grain harvesting led to 40–50% increases in grain water content and 8–34% decreases in the amount of SDS‐unextractable monomeric protein. At increased grain water contents the fertiliser rate was negatively related to the amount of grain SDS‐unextractable protein. CONCLUSION: Accumulation and polymerisation of grain storage proteins are predetermined events in wheat. Grain moisture content is negatively related to grain storage protein polymerisation, although the rate of decrease is influenced by the fertiliser regime. Copyright © 2008 Society of Chemical Industry  相似文献   
998.
The primary aim of this study was to determine the oxidative stability of argan oils by using peroxides and conjugated diene hydroperoxides measurements as analytical indicators. Both food and cosmetic argan oils were investigated. Their oxidative stability was also determined by monitoring the relative changes of their fatty acid profiles by 1H NMR. In addition, valuable information regarding minor components as well as the acyl positional distribution, were obtained for both grades by high field 1H and 13C NMR, respectively. Given that the cosmetic and food grades have a similar profile and content of phenolic antioxidants, vitamers, and squalene, it appears that the ratio of fatty acid aliphatic to bisallylic CH2 groups, much higher in argan oils than in other vegetable oils, is responsible for their higher thermal stability.  相似文献   
999.
The effectiveness of absorbent polymers as packing materials alternative to adsorbents in the interface of the on-line coupling of RPLC to GC via PTV for the analysis of terpenes in orange juice was evaluated. To that aim, a comparative study of an absorbent (polydimethylsiloxane, PDMS), and an adsorbent (Tenax TA) was carried out. As a result, satisfactory repeatability was achieved from both packing materials obtaining relative standard deviation values lower than 10% in most cases. Regarding sensitivity, higher recoveries and far lower detection limits were however attained by using PDMS as the packing material inside the PTV injector. Specifically for PDMS the recoveries varied from 52% to 63% whereas in the case of Tenax TA values ranging from 10% to 22% were obtained. Detection limits varied from 1.5 to 1.9 ppb for PDMS and from 30 to 1900 ppb with Tenax TA. In addition to the sensitivity enhancement, PDMS proved to be more effective in the elimination of the solvent coming from the RPLC-pre-separation. Besides, PDMS is more thermally stable and, as a consequence, it results in lesser degradation products.  相似文献   
1000.
Consumers and corporate end users are regularly faced with the challenge of adapting to new technology tools and their user interfaces. Understanding the role of user experience in using these new interfaces is an important aspect of assessing and planning for how new innovations are received. Through a controlled laboratory experiment in the information retrieval domain, we find that the effect of task (web search) familiarity on performance depends on the task structure (open-ended versus closed-ended) and the degree of tool familiarity (a traditional textual list versus a novel graphical interface for presenting web search results). Our results show that task experience has a positive effect on performance when the task structure is closed-ended and the interface is familiar, and a negative effect when the task structure is open-ended and the interface is unfamiliar. This study not only adds to the literature on user experience in the context of IT use, but also has practical implications for the testing and adoption of new technologies, indicating that novices may be better, or at least an important group, for testing truly novel tools and their interfaces.  相似文献   
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