999 resultados para compound-leaved groups


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In environments where distributed team formation is key, and defections are possible, the use of trust as social capital allows social norms to be defied and compared. An agent can use this information, when invited to join a group or collation, to decide whether or not its utility will be increased by joining. In this work a social network approach is used to define and reason about the relationships contained in the agent community. Previous baseline work is extended with two decision making mechanisms. These are compared by simulating an abstract grid-like environment, and preliminary results are reported.

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Hereditary non-polyposis colorectal cancer (HNPCC), predominantly due to germline MLH1/MSH2 mutations, is the commonest form of hereditary colorectal cancer (CRC), but data in Asians are sparse. We sequenced the MLH1/MSH2 coding and promoter core regions in CRC patients diagnosed below age 40, and/or with multiple primary cancers or familial cancer clustering suggestive of HNPCC, and correlated deleterious mutations with clinical and tumour features. Forty-six Chinese, Malay and Indian kindreds participated. Of the 153 cancers reported in the 46 kindreds, stomach (14%) and urogenital cancers (13%) were the most common extracolonic cancers, whereas endometrial cancer comprised only 7%. Eleven different MLH1 and 12 MSH2 mutations were identified, including nine novel and four recurring mutations in the Chinese. One Indian was a compound heterozygote for an MLH1 and MSH2 mutation. The MLH1/MSH2 mutation data in the Malays and the Indians represents the first in these ethnic groups. Factors strongly associated with deleterious mutations were the Amsterdam criteria, family history of stomach or multiple primary cancers, and MSI-high tumours, whereas family history of endometrial cancer and young cancer age alone correlated poorly. Distinct clinical and molecular characteristics were identified among Asian HNPCC kindreds and may have important clinical implications.

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Beliefs about personhood are understood to be a defining feature of individualism-collectivism (I-C), but they have been insufficiently explored, given the emphasis of research on values and self-construals. We propose the construct of contextualism, referring to beliefs about the importance of context in understanding people, as a facet of cultural collectivism. A brief measure was developed and refined across 19 nations (Study 1: N = 5,241), showing good psychometric properties for cross-cultural use and correlating well at the nation level with other supposed facets and indicators of I-C. In Study 2 (N = 7,623), nation-level contextualism predicted ingroup favoritism, corruption and differential trust of ingroup and outgroup members, while controlling for other facets of I-C, across 34 nations. We conclude that contextualism is an important part of cultural collectivism. This highlights the importance of beliefs alongside values and self-representations, and contributes to a wider understanding of cultural processes.

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The proton NMR spectra of aryl n-propyl sulfides gave rise to what may appear to be first-order proton NMR spectra. Upon oxidation to the corresponding sulfone, the spectra changed appearance dramatically and were clearly second-order. A detailed analysis of these second-order spectra, in the sulfone series, provided vicinal coupling constants which indicated that these compounds had a moderate preference for the anti-conformer, reflecting the much greater size of the sulfone over the sulfide. It also emerged, from this study, that the criterion for observing large second-order effects in the proton NMR spectra of 1,2-disubstituted ethanes was that the difference in vicinal coupling constants must be large and the difference in geminal coupling constants must be small. n-Propyl triphenylphosphonium bromide and 2-trimethylsilylethanesulfonyl chloride, and derivatives thereof, also exhibited second-order spectra, again due to the bulky substituents. Since these spectra are second-order due to magnetic nonequivalence of the nuclei in question, not chemical shifts, the proton spectra are perpetually second-order and can never be rendered first-order by using higher field NMR spectrometers.

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The new anionic functionalized aryldiamine ligands [2,6-(Me(2)NCH(2))(2)-4-R-C6H2](-) (R = Me(3)SiC=C, C6H5, Me(3)Si), formally derived from [2,6-(Me(2)NCH(2))(2)C6H3](-), have been prepared as their lithium compounds. The compound [Li{2,6-(Me(2)NCH(2))(2)-4-Ph-C6H2}](2) crystallizes in the monoclinic space group C2/c (no. 15) with a = 13.1225(5), b = 13.5844(7), c = 15.9859(12) Angstrom, beta = 105.329(5)degrees, V = 3264.0(3)Angstrom(3), Z = 4. The structure refinement converged to R(1) = 0.0374 for 2037 observed reflections [F-o>4 sigma(F-o)] and wR(2) = 0.0922 for 2560 unique data. The organolithium compounds have been used in transmetalation reactions to give the corresponding functionalized organoruthenium(II) complexes [Ru-II{2,6-(Me(2)NCH(2))(2)-4-R-C6H2}(terpy)]Cl-+(-) (terpy = 2,2';6',2 ''-terpyridine). The Ru-II species with R = HC = C has also been synthesized.

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Behavioral effects of a novel anti-inflammatory SEN1176 were investigated. This pyrrolo[3,2-e][1,2,4]triazolo[1,5-a]pyrimidine suppresses amyloid-ß (Aß)1-42-induced macrophage production of nitric oxide, TNF-a, IL-1ß, and IL-6 in a dose-dependent fashion, an activity profile consistent with SEN1176 being a neuroinflammation inhibitor. Using male Sprague-Dawley rats, SEN1176 was examined relative to detrimental behavioral effects induced following bilateral intrahippocampal (IH) injections of aggregated Aß1-42. The rats were trained to respond under an alternating-lever cyclic-ratio (ALCR) schedule of food reinforcement, enabling measurement of parameters of operant performance that reflect aspects of learning and memory. Under the ALCR schedule, orally administered SEN1176 at 5, 20, or 30 mg/kg was effective in reducing the behavioral deficit caused by bilateral IH aggregated Aß1-42 injections in a dose-related manner over a 90-day treatment period. SEN1176 at 20 and 30 mg/kg significantly reduced lever switching errors and, at doses of 5, 10, and 30 mg/kg, significantly reduced incorrect lever perseverations, indicating a reduction of the behavioral deficit induced as a result of inflammation following IH Aß1-42 injections. When treatment with SEN1176 was instigated 30 days after IH Aß1-42 injections, it resulted in progressive protection, and withdrawal of SEN1176 treatment 60 days after IH Aß1-42 injections revealed partial retention of the protective effect. SEN1176 also significantly reduced numbers of activated astrocytes adjacent to the aggregated Aß1-42 injection sites. These results indicate the potential of SEN1176 for alleviating chronic neuroinflammatory processes related to brain Aß deposition that affect learning and memory in Alzheimer's disease.

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This study assessed the effects of increasing dietary fibre levels in concentrate rations and providing access to straw in racks on the welfare of pregnant sows housed in small static groups. In a 2 x 2 factorial design experiment, 128 Large White x Landrace pregnant sows were offered one of two diets: (i) High fibre diet with 9% crude fibre, or (ii) Control diet with 4.5% CF, and one of two levels of access to a foraging substrate: (i) access to straw in racks or (ii) no straw. The study was replicated eight times using groups of four sows, and treatment periods lasted four weeks. Sows were housed in pens with voluntary cubicles and a slatted exercise area and were offered a wet diet twice a day. Back-fat levels were measured before sows were mixed into groups at 28 days post partum, and four weeks later. Aggressive interactions were recorded on the day of mixing, and injury scores were recorded one week post mixing. Scan sampling was used to collect data on general activity, posture and location of the sows, and on sham-chewing and bar-biting behaviours across the treatment period. In addition, detailed focal observations were carried out on all sows across the treatment period. Straw usage was also recorded. There were no treatment effects on changes in back-fat levels over the treatment period. Treatments had no effect on post-mixing aggression or on injury scores. However, focal observations showed that sows with access to straw were involved in fewer bouts of head-thrusting over the treatment period. Control diet sows spent more time inactive than sows on the high fibre diet, however high fibre diet sows spent more time lying with eyes closed than sows on the control diet. Sows on the high fibre diet with access to straw showed less sham-chewing and bar-biting behaviour than sows in other treatments. These results show that although a diet containing 9% crude fibre promoted resting behaviour, it was necessary to combine it with access to straw to reduce stereotypic behaviour of sows in small static groups.

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The qualitative aspects of the Contingent Valuation Method (CVM) are largely ignored by (environmental) economists. This paper aims to instigate a discussion on (a) the usefulness of qualitative data to the contingent valuation process in general; and (b) the use and applicability of the focus group method in particular. We consider the range and uses of focus groups within the CVM and highlight problems with their analysis that have, to date, largely been ignored. A potential solution to circumvent the problem of non-independence of group data is suggested. While there are several distinct and worthwhile uses for qualitative data, focus groups should not automatically be taken as the only or best method to produce these insights even though they are the major one considered in this article. (C) 1999 Elsevier Science B.V. All rights reserved.