257 resultados para SNAP


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The snap-through and pull-in instabilities of the micromachined arch-shaped beams under an electrostatic loading are studied both theoretically and experimentally. The pull-in instability that results in a system collision with an electrode substrate may lead to a system failure and, thus, limits the system maximum displacement. The beam/plate structure with a flat initial configuration under an electrostatic loading can only experience the pull-in instability. With the different arch configurations, the structure may experience either only the pull-in instability or the snap-through and pull-in instabilities together. As shown in our computation and experiment, those arch-shaped beams with the snap-through instability have the larger maximum displacement compared with the arch-shaped beams with only the pull-in stability and those with the flat initial configuration. The snap-through occurs by exerting a fixed load, and the structure experiences a discontinuous displacement jump without consuming power. Furthermore, after the snap-through jump, the structures are demonstrated to have the capacity to withstand further electrostatic loading without pull-in. Those properties of consuming no power and increasing the structure deflection range without pull-in is very useful in microelectromechanical systems design, which can offer better sensitivity and tuning range.

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SNARE蛋白家族是所有真核细胞胞吐及分泌作用中的关键因子,由其介导的运输囊泡膜与靶膜的锚靠、融合为胞内蛋白的运出提供了一条重要途径。体外试验表明,Syntaxin6-Syntaxin7-Vti1b,SNAP-23-Syntaxin4等SNARE核心蛋白之间精确的相互作用是哺乳动物巨噬细胞肿瘤坏死因子α (TNF-α)运输和分泌的必备条件,在机体非特异性免疫应答反应过程中起重要作用。 本研究受上述启示,旨在揭示SNARE蛋白在海洋鱼类免疫细胞内重要细胞因子白细胞介素1β (IL-1β)的分泌过程中的作用。参照Percoll密度梯度离心技术,从鲈鱼头肾组织分离纯化巨噬细胞进行稳定培养;利用RT-PCR方法克隆出鲈鱼t-SNARE蛋白SNAP-23和Syntaxin3的部分cDNA序列,再结合先前克隆的VAMP2和已知的鲈鱼IL-1β,TNF-α和IL-8的基因序列,设计特异性引物。利用Real-time PCR技术在mRNA水平上精确测定鲈鱼巨噬细胞中上述6种基因在革兰氏阴性菌脂多糖(LPS)分子刺激下的表达变化,发现SNAP-23基因与三种细胞因子基因的表达正相关;通过免疫印迹检测SNAP-23蛋白表达变化,利用酶联免疫吸附试验(ELISA)检测IL-1β的分泌水平,在蛋白水平上验证了SNAP-23表达与IL-1β分泌的正相关性;利用5`RACE和3`RACE技术克隆出鲈鱼SNAP-23全长基因,结合定点突变策略和靶向PCR克隆手段,构建鲈鱼SNAP-23野生型融合质粒pEGFP-SNAP-23wt,Cys缺失突变融合质粒pEGFP-SNAP-23ΔCys和模拟E型肉毒神经毒素(BoNT/E)切割突变融合质粒pEGFP-SNAP-23ΔBoNT/E,以及鲈鱼IL-1β野生型融合表达质粒IL-1β-pEGFP和IL-1β-pEYFP。所有融合蛋白均在鲈鱼巨噬细胞内成功表达,结合ELISA实验结果发现,SNAP-23野生型的表达对IL-1β的分泌有促进作用,而Cys缺失突变体的表达则抑制IL-1β向胞外分泌。首次证实了鱼类巨噬细胞内SNAP-23蛋白在IL-1β分泌过程中的重要作用。此外通过与GFP共表达,定位了IL-1β分子在巨噬细胞内的分布,发现新合成的IL-1β分子很可能像TNFα一样经“内质网-胞质-伪足-胞外” 的分泌路径运出胞外。

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Understanding tumor vascular dynamics through parameters such as blood flow and oxygenation can yield insight into tumor biology and therapeutic response. Hyperspectral microscopy enables optical detection of hemoglobin saturation or blood velocity by either acquiring multiple images that are spectrally distinct or by rapid acquisition at a single wavelength over time. However, the serial acquisition of spectral images over time prevents the ability to monitor rapid changes in vascular dynamics and cannot monitor concurrent changes in oxygenation and flow rate. Here, we introduce snap shot-multispectral imaging (SS-MSI) for use in imaging the microvasculature in mouse dorsal-window chambers. By spatially multiplexing spectral information into a single-image capture, simultaneous acquisition of dynamic hemoglobin saturation and blood flow over time is achieved down to the capillary level and provides an improved optical tool for monitoring rapid in vivo vascular dynamics.

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1. Catabolic processes of the phasic and catch parts of the adductor muscle ofPlacopecten magellanicus have been studied in relation to valve snap and valve closure responses. It is concluded that the snap response is powered by both parts of the adductor muscle and the valve closure response is powered exclusively by the catch part. 2. Both parts of the adductor muscle show a high glycolytic potential, reflected by high levels of glycolytic enzymes (Table 1) and high glycogen levels (Table 2). Lactate dehydrogenase could not be detected. In contrast, octopine dehydrogenase shows high activities in both parts of the adductor muscle. It is therefore concluded that a main anaerobic pathway in both tissues is the breakdown of glycogen to octopine. In the catch part, however, a considerable amount of the pyruvate formed from glycogen may also be converted into alanine (see below). The glycolytic flux in the catch part is much higher during the snap response than during valve closure. 3. The absence of phosphoenolpyruvate carboxykinase in the adductor muscle ofP. magellanicus and the observed changes in aspartate, alanine and succinate demonstrate that the energy metabolism in the catch part during valve closure shows great similarities to that which occurs only in the initial stage of anaerobiosis in the catch adductor muscle of the sea musselMytilus edulis L. 4. Arginine kinase activity and arginine phosphate content of the phasic part are much higher than those of the catch part (Tables 1 and 3). This may explain why in the phasic part during the snap response most ATP equivalents are derived from arginine phosphate, and in the catch part during both valve responses most are derived from glycolysis (Table 6). Despite the limited contribution of glycolysis in the phasic part during the snap response, the glycolytic flux increases by a factor of at least 75. 5. Evidence is obtained that octopine is neither transported from one part of the adductor muscle to the other, nor from the adductor muscle to other tissues.

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1. Catabolic processes of the phasic and catch parts of the adductor muscle ofPlacopecten magellanicus have been studied in relation to valve snap and valve closure responses. It is concluded that the snap response is powered by both parts of the adductor muscle and the valve closure response is powered exclusively by the catch part. 2. Both parts of the adductor muscle show a high glycolytic potential, reflected by high levels of glycolytic enzymes (Table 1) and high glycogen levels (Table 2). Lactate dehydrogenase could not be detected. In contrast, octopine dehydrogenase shows high activities in both parts of the adductor muscle. It is therefore concluded that a main anaerobic pathway in both tissues is the breakdown of glycogen to octopine. In the catch part, however, a considerable amount of the pyruvate formed from glycogen may also be converted into alanine (see below). The glycolytic flux in the catch part is much higher during the snap response than during valve closure. 3. The absence of phosphoenolpyruvate carboxykinase in the adductor muscle ofP. magellanicus and the observed changes in aspartate, alanine and succinate demonstrate that the energy metabolism in the catch part during valve closure shows great similarities to that which occurs only in the initial stage of anaerobiosis in the catch adductor muscle of the sea musselMytilus edulis L. 4. Arginine kinase activity and arginine phosphate content of the phasic part are much higher than those of the catch part (Tables 1 and 3). This may explain why in the phasic part during the snap response most ATP equivalents are derived from arginine phosphate, and in the catch part during both valve responses most are derived from glycolysis (Table 6). Despite the limited contribution of glycolysis in the phasic part during the snap response, the glycolytic flux increases by a factor of at least 75. 5. Evidence is obtained that octopine is neither transported from one part of the adductor muscle to the other, nor from the adductor muscle to other tissues.

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In the academic debate regarding the influences between urban form, built environment and travel patterns, a specific idea that has taken hold is that more compact urban development around railway stations, often referred to as Transit Oriented Development (TOD), contributes to the control of vehicle travel and to more sustainable metropolitan systems. According to this general principle this work proposes a GIS accessibility tool for the design of polycentric transit oriented scenario: SNAP - Station Network Accessibility Planning tool. In the first part the state of the art on Transit Oriented Development policies in Europe is presented with a focus on three study cases. In the second part the SNAP tool is described, with remarks to the approach, the methodology and the used indicators. Furthermore the paper discusses an application to the metropolitan area of Naples.

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La presente tesis analiza las relaciones del Ministerio del Ambiente (MAE), con el Fondo Ambiental Nacional, FAN, en el marco de la alianza estratégica que mantienen para apoyar la conservación de la biodiversidad del Sistema Nacional de Áreas Protegidas, SNAP. Con este enfoque, se revisa puntualmente el marco jurídico e institucional para la gestión de la biodiversidad en general y del SNAP en particular; y en este contexto se resume la trayectoria del SNAP, su conformación, problemática y situaciones recurrentes de debilidades para su gestión, desde 1973 hasta la actualidad. Se revisan el contexto político y económico que motivaron la creación y luego puesta en marcha del FAN; sus características legales y organizacionales, ámbito de acción y enfoque estratégico; así como las características de la alianza MAE FAN, direccionada a apoyar al MAE en la gestión de recursos financieros que apoyen la gestión del SNAP, la cual se agravó como resultado de la implementación en 1998 de la Ley Especial de Galápagos, que eliminó los fondos que subsidiariamente recibía el SNAP. Se analiza los sistemas y modelos de gestión, tanto del MAE, como del FAN, para ubicar en ellos los arreglos institucionales realizados para implementar la alianza de apoyo al SNAP; y en este sentido se describen el diseño, elaboración e implementación del Fondo de gastos operativos básicos, para las áreas protegidas, FAP, como un mecanismo de capitalización de un fondo patrimonial cuyos rendimientos se destinan a apoyar la gestión de las áreas protegidas del SNAP; mecanismo implementado conjuntamente por las dos entidades desde el 2002. Luego de una revisión de la implementación de los macro procesos del Fondo de áreas protegidas: FAP, se analizan los planes estratégicos del SNAP y del FAN, para ubicar los avances, reflexionar sobre los problemas recurrentes; y en base de ello proceder a proponer recomendaciones que fortalezcan la alianza MAE y FAN, tanto en la implementación del FAP, como en potenciales temas de interacción entre el MAE y el FAN, para un fortalecimiento más integral a la gestión del SNAP como un objetivo de país, a cuyo cumplimiento el FAN debe contribuir de manera más eficiente y con la consiguiente corresponsabilidad del MAE.

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Background Recent reports have suggested that the prevalence of autism and related spectrum disorders (ASDs) is substantially higher than previously recognised. We sought to quantify prevalence of ASDs in children in South Thames, UK. Methods Within a total population cohort of 56946 children aged 9-10 years, we screened all those with a current clinical diagnosis of ASD (n=255) or those judged to be at risk for being an undetected case (n=1515). A stratified subsample (n=255) received a comprehensive diagnostic assessment, including standardised clinical observation, and parent interview assessments of autistic symptoms, language, and intelligence quotient (IQ). Clinical consensus diagnoses of childhood autism and other ASDs were derived. We used a sample weighting procedure to estimate prevalence. Findings The prevalence of childhood autism was 38.9 per 10000 (95% CI 29.9-47.8) and that of other ASDs was 77.2 per 10000 (52.1-102.3), making the total prevalence of all AS Ds 116.1 per 10000 (90.4-141.8). A narrower definition of childhood autism, which combined clinical consensus with instrument criteria for past and current presentation, provided a prevalence of 24.8 per 10 000 (17.6-32.0). The rate of previous local identification was lowest for children of less educated parents. Interpretation Prevalence of autism and related ASDs is substantially greater than previously recognised. Whether the increase is due to better ascertainment, broadening diagnostic criteria, or increased incidence is unclear. Services in health, education, and social care will need to recognise the needs of children with some form of ASD, who constitute 1% of the child population.

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We report rates of regression and associated findings in a population derived group of 255 children aged 9-14 years, participating in a prevalence study of autism spectrum disorders (ASD); 53 with narrowly defined autism, 105 with broader ASD and 97 with non-ASD neurodevelopmental problems, drawn from those with special educational needs within a population of 56,946 children. Language regression was reported in 30% with narrowly defined autism, 8% with broader ASD and less than 3% with developmental problems without ASD. A smaller group of children were identified who underwent a less clear setback. Regression was associated with higher rates of autistic symptoms and a deviation in developmental trajectory. Regression was not associated with epilepsy or gastrointestinal problems.

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Background Autism spectrum disorder (ASD) was once considered to be highly associated with intellectual disability and to show a characteristic IQ profile, with strengths in performance over verbal abilities and a distinctive pattern of ‘peaks’ and ‘troughs’ at the subtest level. However, there are few data from epidemiological studies. Method Comprehensive clinical assessments were conducted with 156 children aged 10–14 years [mean (s.d.)=11.7 (0.9)], seen as part of an epidemiological study (81 childhood autism, 75 other ASD). A sample weighting procedure enabled us to estimate characteristics of the total ASD population. Results Of the 75 children with ASD, 55% had an intellectual disability (IQ<70) but only 16% had moderate to severe intellectual disability (IQ<50); 28% had average intelligence (115>IQ>85) but only 3% were of above average intelligence (IQ>115). There was some evidence for a clinically significant Performance/Verbal IQ (PIQ/VIQ) discrepancy but discrepant verbal versus performance skills were not associated with a particular pattern of symptoms, as has been reported previously. There was mixed evidence of a characteristic subtest profile: whereas some previously reported patterns were supported (e.g. poor Comprehension), others were not (e.g. no ‘peak’ in Block Design). Adaptive skills were significantly lower than IQ and were associated with severity of early social impairment and also IQ. Conclusions In this epidemiological sample, ASD was less strongly associated with intellectual disability than traditionally held and there was only limited evidence of a distinctive IQ profile. Adaptive outcome was significantly impaired even for those children of average intelligence.

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A novel technique for micro-machining millimeter and submillimeter-wave rectangular waveguide components is reported. These are fabricated in two halves which simply snap together, utilizing locating pins and holes, and are physically robust, and cheap, and easy to manufacture. In addition, S-parameter measurements on these structures are reported for the first time and display lower loss than previously reported micro-machined rectangular waveguides.

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Background
Lifestyle risk factors like smoking, nutrition, alcohol consumption, and physical inactivity (SNAP) are the main behavioural risk factors for chronic disease. Primary health care is an appropriate setting to address these risk factors in individuals. Generalist community health nurses (GCHNs) are uniquely placed to provide lifestyle interventions as they see clients in their homes over a period of time. The aim of the paper is to examine the impact of a service-level intervention on the risk factor management practices of GCHNs.

Methods
The trial used a quasi-experimental design involving four generalist community nursing services in NSW, Australia. The services were randomly allocated to either an intervention group or control group. Nurses in the intervention group were provided with training and support in the provision of brief lifestyle assessments and interventions. The control group provided usual care. A sample of 129 GCHNs completed surveys at baseline, 6 and 12 months to examine changes in their practices and levels of confidence related to the management of SNAP risk factors. Six semi-structured interviews and four focus groups were conducted among the intervention group to explore the feasibility of incorporating the intervention into everyday practice.

Results

Nurses in the intervention group became more confident in assessment and intervention over the three time points compared to their control group peers. Nurses in the intervention group reported assessing physical activity, weight and nutrition more frequently, as well as providing more brief interventions for physical activity, weight management and smoking cessation. There was little change in referral rates except for an improvement in weight management related referrals. Nurses’ perception of the importance of ‘client and system-related’ barriers to risk factor management diminished over time.

Conclusions
This study shows that the intervention was associated with positive changes in self-reported lifestyle risk factor management practices of GCHNs. Barriers to referral remained. The service model needs to be adapted to sustain these changes and enhance referral.

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Background
The risk factors for chronic disease, smoking, poor nutrition, hazardous alcohol consumption, physical inactivity and weight (SNAPW) are common in primary health care (PHC) affording opportunity for preventive interventions. Community nurses are an important component of PHC in Australia. However there has been little research evaluating the effectiveness of lifestyle interventions in routine community nursing practice. This study aimed to address this gap in our knowledge.

Methods
The study was a quasi-experimental trial involving four generalist community nursing (CN) services in New South Wales, Australia. Two services were randomly allocated to an ‘early intervention’ and two to a ‘late intervention’ group. Nurses in the early intervention group received training and support in identifying risk factors and offering brief lifestyle intervention for clients. Those in the late intervention group provided usual care for the first 6 months and then received training. Clients aged 30–80 years who were referred to the services between September 2009 and September 2010 were recruited prior to being seen by the nurse and baseline self-reported data collected. Data on their SNAPW risk factors, readiness to change these behaviours and advice and referral received about their risk factors in the previous 3 months were collected at baseline, 3 and 6 months. Analysis compared changes using univariate and multilevel regression techniques.

Results
804 participants were recruited from 2361 (34.1%) eligible clients. The proportion of clients who recalled receiving dietary or physical activity advice increased between baseline and 3 months in the early intervention group (from 12.9 to 23.3% and 12.3 to 19.1% respectively) as did the proportion who recalled being referred for dietary or physical activity interventions (from 9.5 to 15.6% and 5.8 to 21.0% respectively). There was no change in the late intervention group. There a shift towards greater readiness to change in those who were physically inactive in the early but not the comparison group. Clients in both groups reported being more physically active and eating more fruit and vegetables but there were no significant differences between groups at 6 months.

Conclusion
The study demonstrated that although the intervention was associated with increases in advice and referral for diet or physical activity and readiness for change in physical activity, this did not translate into significant changes in lifestyle behaviours or weight. This suggests a need to facilitate referral to more intensive long-term interventions for clients with risk factors identified by primary health care nurses.

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Snap’ deploys the queer cliché of becoming-sailor as a trope for recognition in the amorous encounter and literalises the ‘copycat’ as its catalyst. As Girard argues (1973), the human is foremost mimetic: this story makes its claim for originality and authenticity of connection through the playful recycling of cliché.‘Snap’ eschews the relative affectlessness of some metafiction by staging an amorous approach under the shadow of mortality. It exploits the liminal moment of modernist short fiction to summon the ‘manifold’ of experience. Here, love opens a space of intertextual esonance (Costello 2007), including motifs of Genet (masquerade), Duras (haunting) and Maurice Blanchot (the infinite approach), by writing the threshold of encounter as the intensive silence of wond