275 resultados para adaption


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Fatty acid desaturases are enzymes that introduce double bonds into the hydrocarbon chains of fatty acids. The fatty acid desaturases from 37 cyanobacterial genomes were identified and classified based upon their conserved histidine-rich motifs and phylogenetic analysis, which help to determine the amounts and distributions of desaturases in cyanobacterial species. The filamentous or N-2-fixing cyanobacteria usually possess more types of fatty acid desaturases than that of unicellular species. The pathway of acyl-lipid desaturation for unicellular marine cyanobacteria Synechococcus and Prochlorococcus differs from that of other cyanobacteria, indicating different phylogenetic histories of the two genera from other cyanobacteria isolated from freshwater, soil, or symbiont. Strain Gloeobacter violaceus PCC 7421 was isolated from calcareous rock and lacks thylakoid membranes. The types and amounts of desaturases of this strain are distinct to those of other cyanobacteria, reflecting the earliest divergence of it from the cyanobacterial line. Three thermophilic unicellular strains, Thermosynechococcus elongatus BP-1 and two Synechococcus Yellowstone species, lack highly unsaturated fatty acids in lipids and contain only one Delta 9 desaturase in contrast with mesophilic strains, which is probably due to their thermic habitats. Thus, the amounts and types of fatty acid desaturases are various among different cyanobacterial species, which may result from the adaption to environments in evolution. Copyright (c) 2008 Xiaoyuan Chi et al.

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The psychrotrophic Antarctic alga, Chlorella vulgaris NJ-7, grows under an extreme environment of low temperature and high salinity. In an effort to better understand the correlation between fatty acid metabolism and acclimation to Antarctic environment, we analyzed its fatty acid compositions. An extremely high amount of Delta(12) unsaturated fatty acids was identified which prompted us to speculate about the involvement of Delta(12) fatty acid desaturase in the process of acclimation. A full-length cDNA sequence, designated CvFAD2, was isolated from C. vulgaris NJ-7 via reverse transcription polymerase chain reaction (RT-PCR) and RACE methods. Sequence alignment and phylogenetic analysis showed that the gene was homologous to known microsomal Delta(12)-FADs with the conserved histidine motifs. Heterologous expression in yeast was used to confirm the regioselectivity and the function of CvFAD2. Linoleic acid (18:2), normally not present in wild-type yeast cells, was detected in transformants of CvFAD2. The induction of CvFAD2 at an mRNA level under cold stress and high salinity is detected by real-time PCR. The results showed that both temperature and salinity motivated the upregulation of CvFAD2 expression. The accumulation of CvFAD2 increased 2.2-fold at 15A degrees C and 3.9-fold at 4A degrees C compared to the alga at 25A degrees C. Meanwhile a 1.7- and 8.5-fold increase at 3 and 6% NaCl was detected. These data suggest that CvFAD2 is the enzyme responsible for the Delta(12) fatty acids desaturation involved in the adaption to cold and high salinity for Antarctic C. vugaris NJ-7.

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本文作者在研究多机器人协调的基础上,将多机器人作为一个整体,从系统的角度研究多机器人系统的整体行为和组织结构.以人工智能的多自主体系统为理论基础,以网络通讯和分布数据库为技术基础,设计了多机器人分布自主协作系统的体系结构,提出了实现该系统需要研究的内容和解决的关键技术,介绍了我们在这方面的工作

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The arguments on self discrepancy can be traced back to the old ages, but the systematic investigations were started by Higgins et al. at 1985.Compared to the large number of foreign studies, only a few ones have been conducted in our own country. Numerous characteristics of undergruaduate’s actual-ideal discrepancy and a great many determinative factors have been found as well as many of its negative effects—especially the greater the actual-ideal discrepancy, the more negative on the mind and behavior. Nevertheless, there are still many issues to be solved, such as the extend of the undergruaduate’s actual-ideal discrepancy level in own country. On the other hand, although there are a great many internal and external determinative factors of actual-ideal discrepancy, how they overally influence the discrepancy of the same individual is still unknown; to what extent does actual-ideal discrepancy influence the human mind and behavior and whether the influence is positive or negtive? This research collected a sample consisting of 4 undergraduate grades and 5 majors from a middle-ranked university. We adopted questionnaires in the study, and analyzed the data using correlation analysis, regression analysis, variances analysis, and path analysis. Our aim focused on the general characteristics of the undergruaduate’s actual-ideal discrepancy in own country, the overall working mechanism of the determinative factors including environmental and personal factors on the actual-ideal discrepancy of the same individual, and the effects of the actual-ideal discrepancy on psychological adaption, motivation, and behavior. The main results are as following: (1)The improved measurement instrument possesses good validity and reliability, and can be used in future research. (2) The actual-ideal discrepancy level among undergraduates is slightly bellow medium. The proportion of undergraduates who have a higher actual-ideal discrepancy level is small. There is significant gender difference in actual-ideal discrepancy level, but no significant difference across different majors and grades. (3)This research probed the overall working mechanism of the parenting style(environmental factors) and the personality factors(personal factors) including stability, flexibility, cleverness, and esteem on the undergruaduate’s actual-ideal discrepancy. The results shows that the parenting style of warmth and understanding, stability, flexibility, and esteem influence the actual-ideal discrepancy. Esteem entirely moderate the relationship between the parenting style of warmth and understanding and actual-ideal discrepancy, partially moderate the relationship between the flexibility, stability and actual-ideal discrepancy. Furthermore, the above factors can be order as stability, flexibility, and parenting style of warmth and understanding in terms of decreasing impact on the actual-ideal discrepancy. No significant effect of cleverness and other parenting style was found. The parenting style of warmth and understanding, stability, and flexibility interactively influence the actual-ideal discrepancy in the following manner: the stability and flexibility, both of which have independent influence on the actual-ideal discrepancy, entirely moderate the relationship between the parenting style of warmth and understanding and actual-ideal discrepancy. (4) Actual-ideal discrepancy plays a negative role in adaption indices, including self-efficacy, self-identity, self-actualization. Actual-ideal discrepancy also has negative effects on the 9 symptoms measured by SCL-90, vitality, approach motivation, avoidance motivation, and performance goals. No significant influence on mastering goals was found. Actual-ideal discrepancy uniquely correlates with depression symptom. The above results contribute from the point of self-discrepancy to the understanding of self-identity of undergraduates, and they enrich the knowledge of the development of self and contribute to the understanding of the development of human personality.This research advances on the two key problems of the developmental mechanism of actual-ideal discrepancy and that promotes the knowledge of the developmental mechanism of actual-ideal discrepancy. The research probed the relationship between the actual-ideal discrepancy and motivation which is an important phenomenon and this enlarges the domain of the actual-ideal discrepancy research. The results make sure that actual-ideal discrepancy is one of the important factors influencing undergruaduate’s mind and behavior. The conclusions can provide reference and guidance in the diagnosis and intervension strategies for mental health education and counseling practice in university.

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The fact of change in human vision sensitivity in color adaption was studied with the method of minimo step change. In this experiment, subjects were asked to judge the just-different threshold on 1° target stimulus which superimposed on 6° background. The target and the surrourding field flicked and different kinds of stimuli were shown to Ss. Data of Pre-color adaption and that of post-color adaption have been compared and ① Evidence of opponent effect is found. This result is contraversary to coefficient law and the "two process" hypothesis are supported; ② Opponent effect is strongly related to the kinds of stimuli ③ When the background light flicks, subjects sensitivity to target stimuli is obviously increased while under the condition of flicking target stimuli less increase can be found. But the increase in sensitivity seem to be not related with color adaption.

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Chinese sports are developing under very complex and unique political, economic, and cultural circumstances in the global age. This study aims to investigate the process of globalization in basketball through an examination of its multidimensional manifestations. The study aligns itself with Ritzer’s (2003, 2007b) conceptualization of dichotomizing the process of globalization into grobalization and glocalization. On that basis, the trajectory of basketball globalization in China is identified as the result of a contextual and competing interplay between the penetration of the NBA and the consequent engagement of Chinese basketball. A qualitative methodological approach was conducted to achieve the research aim. Data were collected from a number of sources, including official documents and semi-structured interviews with relevant basketball participants. The study reveals that globalization and basketball in China, in the political and institutional dimension, is a conflicting process. The universalization of the NBA’s governance model could not be fully assimilated due to the centralization of power in the Chinese government, which is hindering the further professionalization and marketization of basketball. In the economic dimension, the globalization process is seen to interplay with the local basketball market, which is growing thanks to the adaption of the NBA’s marketing strategies. In the cultural dimension, the study demonstrates that the NBA has to some extent cosmopolitanized and consumerized Chinese basketball culture, while resistance from both the state and the Chinese people has risen, creolizing the globalization of basketball culture in China.

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In the last decade, data mining has emerged as one of the most dynamic and lively areas in information technology. Although many algorithms and techniques for data mining have been proposed, they either focus on domain independent techniques or on very specific domain problems. A general requirement in bridging the gap between academia and business is to cater to general domain-related issues surrounding real-life applications, such as constraints, organizational factors, domain expert knowledge, domain adaption, and operational knowledge. Unfortunately, these either have not been addressed, or have not been sufficiently addressed, in current data mining research and development.Domain-Driven Data Mining (D3M) aims to develop general principles, methodologies, and techniques for modeling and merging comprehensive domain-related factors and synthesized ubiquitous intelligence surrounding problem domains with the data mining process, and discovering knowledge to support business decision-making. This paper aims to report original, cutting-edge, and state-of-the-art progress in D3M. It covers theoretical and applied contributions aiming to: 1) propose next-generation data mining frameworks and processes for actionable knowledge discovery, 2) investigate effective (automated, human and machine-centered and/or human-machined-co-operated) principles and approaches for acquiring, representing, modelling, and engaging ubiquitous intelligence in real-world data mining, and 3) develop workable and operational systems balancing technical significance and applications concerns, and converting and delivering actionable knowledge into operational applications rules to seamlessly engage application processes and systems.

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Mast cell activation by polycationic substances is believed to result from a direct activation of G protein alpha subunits and it was suggested that the adaption of amphipathic, alpha-helical conformations would allow the peptide to reach the cytosolic compartment to interact with G proteins (Mousli et al., 1994, Immunopharmacology 27, 1, for review). We investigated the histamine-releasing activity of model peptides as well as analogues of magainin 2 amide and neuropeptide Y with different amphipathicities and alpha-helix content on rat peritoneal mast cells. Amphipathic helicity is not a prerequisite for mast cell activation. Moreover, non-helical magainin peptides with high histamine-releasing activity were less active in the liberation of carboxyfluoresceine from negatively charged liposomes, indicating that peptide-induced mast cell activation and peptide-induced membrane perturbation do not correlate. In contrast to the negligible influence of the secondary structure, amino acid configuration may exert a striking influence on peptide-induced mast cell activation. Thus histamine-release by substance P was markedly impaired when the L-amino acids in the positively charged N-terminal region were replaced by D-amino acids, with [D-Arg(1)]substance P being the most inactive substance P diastereoisomer.

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As a consequence of the accelerating technological development and the impact of cultural globalisation, the transnational aspects of the process of adaptation have become increasingly crucial in recent years. To go back to the very beginnings of the twentieth century and research the historical connections between popular literature, theatre, and film can shed greater light on the origins of these phenomena. By focusing on two case studies from turn-of-the-century crime fiction, this paper examines the extent to which practices of serialisation, translation, and adaptation of literary works contributed to the formation of a transnational market for popular culture. Ernest W. Hornung’s A. J. Raffles and Maurice Leblanc’s Arsène Lupin were the heroes of two crime series that were immediately translated, imitated, and adapted into countless theatrical plays and films all over the world. Given the resemblance between the two characters, the two franchises frequently ended by overlapping. Their ability to move from a medium to another as well as from a country to another was the result of the logic of ‘recycling, remaking, retelling’ (Brian Naremore) that guides not only the process of adaptation but also the creation of any work of popular culture.

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Despite being largely characterised as a social and cognitive disorder, strong evidence indicates the presence of significant sensory-motor problems in Autism Spectrum Disorder (ASD). This paper outlines our progression from initial, broad assessment using the Movement Assessment Battery for Children (M-ABC) to subsequent targeted kinematic assessment. In particular, pronounced ASD impairment seen in the broad categories of manual dexterity and ball skills was found to be routed in specific difficulties on isolated tasks, which were translated into focused experimental assessment. Kinematic results from both subsequent studies highlight impaired use of perception-action coupling to guide, adapt and tailor movement to task demands, resulting in inflexible and rigid motor profiles. In particular difficulties with the use of temporal adaption are shown, with "hyperdexterity" witnessed in ballistic movement profiles, often at the cost of spatial accuracy and task performance. By linearly progressing from the use of a standardised assessment tool to targeted kinematic assessment, clear and defined links are drawn between measureable difficulties and underlying sensory-motor assessment. Results are specifically viewed in-light of perception-action coupling and its role in early infant development suggesting that rather than being 'secondary' level impairment, sensory-motor problems may be fundamental in the progression of ASD. This logical and systematic process thus allows a further understanding into the potential route of observable motor problems in ASD; a vital step if underlying motor problems are to be considered a fundamental aspect of autism and allow a route of non-invasive preliminary diagnosis.

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We previously described a Multilocus Sequence Typing (MLST) scheme based on eight genes that facilitates population genetic and evolutionary analysis of P. acnes. While MLST is a portable method for unambiguous typing of bacteria, it is expensive and labour intensive. Against this background, we now describe a refined version of this scheme based on two housekeeping (aroE; guaA) and two putative virulence (tly; camp2) genes (MLST) that correctly predicted the phylogroup (IA, IA, IB, IC, II, III), clonal complex (CC) and sequence type (ST) (novel or described) status for 91% isolates (n = 372) via cross-referencing of the four gene allelic profiles to the full eight gene versions available in the MLST database (http://pubmlst.org/pacnes/). Even in the small number of cases where specific STs were not completely resolved, the MLST method still correctly determined phylogroup and CC membership. Examination of nucleotide changes within all the MLST loci provides evidence that point mutations generate new alleles approximately 1.5 times as frequently as recombination; although the latter still plays an important role in the bacterium's evolution. The secreted/cell-associated 'virulence' factors tly and camp2 show no clear evidence of episodic or pervasive positive selection and have diversified at a rate similar to housekeeping loci. The co-evolution of these genes with the core genome might also indicate a role in commensal/normal existence constraining their diversity and preventing their loss from the P. acnes population. The possibility that members of the expanded CAMP factor protein family, including camp2, may have been lost from other propionibacteria, but not P. acnes, would further argue for a possible role in niche/host adaption leading to their retention within the genome. These evolutionary insights may prove important for discussions surrounding camp2 as an immunotherapy target for acne, and the effect such treatments may have on commensal lineages. © 2013 McDowell et al.

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The European hare (Lepus europaeus) has declined throughout its native range but invaded numerous regions where it has negatively impacted native wildlife. In southern Sweden, it replaces the native mountain hare (L. timidus) through competition and hybridisation. We investigated temporal change in the invasive range of the European hare in Ireland, and compared its habitat use with the endemic Irish hare (L. timidus hibernicus). The range of the European hare was three times larger and its core range twice as large in 2012–2013 than in 2005. Its rate of radial range expansion was 0.73 km year−1 with its introduction estimated to have occurred ca. 1970. Both species utilised improved and rough grasslands and exhibited markedly similar regression coefficients with almost every land cover variable examined. Irish hares were associated with low fibre and high sugar content grass (good quality grazing) whilst the invader had a greater tolerance for low quality forage. European hares were associated with habitat patch edge density, suggesting it may be more suited to using hedgerows as diurnal resting sites than the Irish hare. Consequently, the invader had a wider niche breadth than the native but their niche overlap was virtually complete. Given the impact of the European hare on native species elsewhere, and its apparent pre-adaption for improved grasslands interspersed with arable land (a habitat that covers 70 % of Ireland), its establishment and range expansion poses a significant threat to the ecological security of the endemic Irish hare, particularly given their ecological similarities.

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BACKGROUND: The impact of bronchiectasis on sedentary behaviour and physical activity is unknown. It is important to explore this to identify the need for physical activity interventions and how to tailor interventions to this patient population. We aimed to explore the patterns and correlates of sedentary behaviour and physical activity in bronchiectasis.

METHODS: Physical activity was assessed in 63 patients with bronchiectasis using an ActiGraph GT3X+ accelerometer over seven days. Patients completed: questionnaires on health-related quality-of-life and attitudes to physical activity (questions based on an adaption of the transtheoretical model (TTM) of behaviour change); spirometry; and the modified shuttle test (MST). Multiple linear regression analysis using forward selection based on likelihood ratio statistics explored the correlates of sedentary behaviour and physical activity dimensions. Between-group analysis using independent sample t-tests were used to explore differences for selected variables.

RESULTS: Fifty-five patients had complete datasets. Average daily time, mean(standard deviation) spent in sedentary behaviour was 634(77)mins, light-lifestyle physical activity was 207(63)mins and moderate-vigorous physical activity (MVPA) was 25(20)mins. Only 11% of patients met recommended guidelines. Forced expiratory volume in one-second percentage predicted (FEV1% predicted) and disease severity were not correlates of sedentary behaviour or physical activity. For sedentary behaviour, decisional balance 'pros' score was the only correlate. Performance on the MST was the strongest correlate of physical activity. In addition to the MST, there were other important correlate variables for MVPA accumulated in ≥10-minute bouts (QOL-B Social Functioning) and for activity energy expenditure (Body Mass Index and QOL-B Respiratory Symptoms).

CONCLUSIONS: Patients with bronchiectasis demonstrated a largely inactive lifestyle and few met the recommended physical activity guidelines. Exercise capacity was the strongest correlate of physical activity, and dimensions of the QOL-B were also important. FEV1% predicted and disease severity were not correlates of sedentary behaviour or physical activity. The inclusion of a range of physical activity dimensions could facilitate in-depth exploration of patterns of physical activity. This study demonstrates the need for interventions targeted at reducing sedentary behaviour and increasing physical activity, and provides information to tailor interventions to the bronchiectasis population.


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As a society we have a responsibility to provide an inclusive built environment. For those with Autistic Spectrum Disorder (ASD) however, the world can be a frightening, difficult and confusing place. The challenge of integrating more fully into society can be distanced by an alienating built environment. This is particularly debilitating for younger children who can find themselves detached from learning and interaction with their peers by uncomfortable surroundings. Subsequently there has been a growing interest in promoting ASD-friendly environments, especially in a school setting. Strategies to date have generally followed a widely accepted reductionist or generalist approach. However, the authors now contend that there needs to be a greater discussion of what truly constitutes an ASD-friendly environment, in conjunction with investigating what strategies best articulate a progressive approach to supporting those, and especially the young, with ASD in our built environment. Hence this paper first introduces some of the challenges faced by those with ASD in trying to cope with their surroundings. It then outlines a triad of challenges to overcome when considering what truly constitutes an ASD-friendly environment. The authors then highlight the need and advantage of supporting change and adaption in our shared inhabited landscape through providing both choice and reassurance for the child with ASD. It is hoped that by increasing awareness and then questioning what genuinely constitutes an ASD-friendly environment, it might ultimately help facilitate greater inclusion of the ASD child into mainstream education and society at large.

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Although the impact of multiple adverse events in childhood is well known, it is equally accepted that the variation in individual trajectories and outcomes is significant. Resilience focuses on positive adaption in the face of adversity, offering a counterbalance to deficit-based research and risk averse, procedurally driven practice. Positive relationships and secure attachments are widely considered to be the cornerstone of resilience, yet, within social work practice, there is a tendency to consider attachment only in relation to children and adults. Three biographical narratives are used to explore resilience and attachment through a narrative identity framework, exploring parents' experiences of multiple adversities over their lifespan, their close relationships, and their experiences of child welfare interventions. It argues for the importance of narrative in social work assessment, particularly in relation to families with complex needs, illustrating how this enables a richer, more nuanced understanding of mothers and fathers as individuals in their own right, and provides insight into how alternative narratives might be better supported and developed.