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21.
This paper presents the first report of the successful ball-milling exfoliation of graphitic filaments (GANF~ carbon nanofibres) into single layer graphene. The addition of small amounts of solvent during the milling process makes it possible to enhance the intercalation of the exfoliating agent (melamine) between the graphene layers, thus promoting exceptional exfoliation. Advantage has also been taken of the fact that the Hansen solubility parameters of graphene are different from those of carbon fibres, which allows single and few-layer graphene to be suspended in a particular solvent, thus discriminating them from poorly exfoliated carbon nanofibres.  相似文献   
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Inulin is a fructooligosaccharide with demonstrable beneficial effects on health. Its effect on the textural and sensory properties of mortadella, a Spanish cooked meat product, was studied. Conventional (23% fat) and reduced‐fat sausages (10% fat) were prepared. Fat reduction yields an energy value reduction close to 33%. In both cases, inulin was incorporated, in powder and as gel form, in sufficient amounts to constitute the 2.5%, 5% and 7.5% of the final product. To evaluate the effect of inulin, instrumental measures of texture and sensory analysis (hedonic test) were performed. Textural analysis indicated that powdered inulin increases hardness and this fact was more evident in reduced‐fat sausages which showed that this changes even at concentrations of 2.5%. However, when inulin was incorporated as a gel, textural parameter changed only when the high levels were assayed (7.5%) showing softer sausages independent of the fat content. Sensory analysis was highly favourable and the overall acceptability was good in all batches in spite of the changes observed in texture. It can be established that this product can be enriched with inulin to a maximum level of 7.5% and preferably as gel with a good sensory quality.  相似文献   
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We report the sequence analysis of a 78,601 bp DNA segment on the left arm of chromosome II of Saccharomyces cerevisiae. This 78·6 kb segment spans the region from the start of a subtelomeric Y′ element up to the ILS1 gene. It contains 49 open reading frames (ORFs) with more than 100 amino acids length including 14 internal and five overlapping ORFs. The gene density, excluding the internal ORFs, was calculated as one ORF per 2·2 kb. Eight ORFs (PKC1, TyA, TyB, ATP1, ROX3, RPL17a, PET112 and ILS1) correspond to previously characterized genes. ORF YBL0718 was identified as CDC27; YBL0706 as TEL1. Four other ORFs show strong similarities to already known genes. The gene product of YBL0838 is 60% identical to the ribosomal protein RPL32 from rat, mouse and man. YBL0701 encodes a protein with significant similarity to the initiation factor eIF2 associated p67 glycoprotein from rat. Eight ORFs were disrupted and the resulting yeast strains analysed with respect to their phenotype. The sequence has been deposited in the EMBL Nucleotide Sequence Database under the Accession Number X79489.  相似文献   
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The construct aloneness, proposed as a basic-level human need, parallel to and of the same valency as attachment, is viewed in the process of development over the life span. It is suggested that focus on attachment and object relations has kept the regulatory function of detachment, and thus aloneness, in partial eclipse. Borrowing from the discourse of psycholinguistics, the authors view aloneness as the unmarked member of a pair of antonyms, aloneness/loneliness, rather than as the marked member of the pair, attached/alone. The contributions of psychoanalysts across models and infant researchers are recalled in the service of tracing the presence of an aloneness need. Examples from psychoanalytic child treatments are offered to illustrate the juxtaposition of aloneness and attachment in analytic discourse at successive developmental stages. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Investigated the transcultural generalizability of the Disability Factor Scales—General (DFS—G) of J. Siller et al (1967) in 658 Jewish Israeli 11th and 12th graders and undergraduates. All Ss filled out a Hebrew translation of the 69-item DFS—G. Factor analysis of the Ss' responses provided support for the replicability of a major part of the DFS—G's structure. Also, a subsample of 114 Ss was administered the Edwards Social Desirability Scale while a subsample of 197 Ss was administered the Marlowe-Crowne Social Desirability Scale. Correlations between some scales of the DFS—G and these 2 measures are discussed as possible evidence that attitudes toward disability may reflect defenses against intra- and interpersonal pressures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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In many animals, chemical signals play an important role in species recognition and may contribute to reproductive isolation and speciation. The Iberian lizards of the genus Podarcis, with up to nine currently recognized lineages that are often sympatric, are highly chemosensory and provide an excellent model for the study of chemically mediated species recognition in closely related taxa. In this study, we tested the ability of male and female lizards of two sister species with widely overlapping distribution ranges (Podarcis bocagei and P. hispanica type 1) to discriminate between conspecific and heterospecific mates by using only substrate-borne chemical cues. We scored the number of tongue flicks directed at the paper substrate by each individual in a terrarium previously occupied by a conspecific or a heterospecific lizard of the opposite sex. Results show that males of P. bocagei and P. hispanica type 1 are capable of discriminating chemically between conspecifics and heterospecifics of the opposite sex, but females are not. These results suggest that differences in female, but not male, chemical cues may underlie species recognition and contribute to reproductive isolation in these species. The apparent inability of females to discriminate conspecific from heterospecific males, which is not because of reduced baseline exploration rates, is discussed in the context of sexual selection theory and species discrimination.  相似文献   
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The environmental impacts of municipal solid waste (MSW) management have been highlighted in China, due to the continually increasing amount of MSW being generated and the limited capacity of waste treatment facilities. Of particular interest is greenhouse gas (GHG) mitigation, aided by the Kyoto Mechanisms. China is an important case study for this global issue; however, an analysis of the entire life cycle of MSW management on GHG emissions is not available for China. This study evaluates the current and possible patterns of MSW management with regard to GHG emissions, using life cycle assessment (LCA), based on the Tianjin case. We assess the baseline scenario, reflecting the existing MSW management system, as well as a set of alternative scenarios, five exploring waste treatment technology innovations and one exploring integrated MSW management, to quantitatively predict potentials of GHG mitigation for Tianjin. Additionally, a sensitivity analysis is used to investigate the influence of landfill gas (LFG) collection efficiency, recycling rate and methodological choice, especially allocation, on the outcomes. The results show GHG emissions from Tianjin's MSW management system amount to 467.34 Mg CO2 eq. per year, based on the treatment of MSW collected in the central districts in 2006, and the key issue is LFG released. The integrated MSW management scenario, combining different improvement options, shows the highest GHG mitigation potential. Given the limited financial support and the current waste management practice in Tianjin, LFG utilization scenario would be the preferred choice. The sensitivity analysis of recycling rate shows an approximately linear relation of inverse proportion between recycling rate and total GHG emissions. Kitchen waste composting makes a considerable contribution to total GHG emissions reduction. Allocation choices result in differences in total quantitative outcomes, but preference orders and contributions analysis are found to be robust, suggesting LCA can support decision making.  相似文献   
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CD22 (Siglec-2) is a B-cell surface inhibitory protein capable of selectively recognising sialylated glycans, thus dampening autoimmune responses against self-antigens. Here we have characterised the dynamic recognition of complex-type N-glycans by human CD22 by means of orthogonal approaches including NMR spectroscopy, computational methods and biophysical assays. We provide new molecular insights into the binding mode of sialoglycans in complex with h-CD22, highlighting the role of the sialic acid galactose moieties in the recognition process, elucidating the conformational behaviour of complex-type N-glycans bound to Siglec-2 and dissecting the formation of CD22 homo-oligomers on the B-cell surface. Our results could enable the development of additional therapeutics capable of modulating the activity of h-CD22 in autoimmune diseases and malignancies derived from B-cells.  相似文献   
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