117 research outputs found
Control Twisting con Adaptación Basada en Cruce por Cero para un Sistema de Columna de Agua Oscilante con Generador Sincrónico
Este trabajo presenta el control de un dispositivo de columna de agua oscilante, que incluye un generador sincrónico de imán permanente, para la extracción óptima de potencia. Se diseñan dos controladores de modo deslizante de segundo orden adaptables, que funcionan de manera robusta en modo deslizante real y muestran una notable mejora en la reducción del chattering cuando se los compara con el mismo esquema con ganancias fijas, al ser probados sobre el modelo completo del sistema
Control para maxima extracción de energía undimotriz por Modos Deslizantes de Segundo Orden real con Ganancias Adaptivas
La optimización del aprovechamiento de la energıa de las olas se está desarrollando fuertemente de manera internacional y Argentina tiene gran potencial de este recurso. Entre todos los dispositivos capaces de transformar la energıa undimotriz, los sistemas de Columna de Agua Oscilante han sido los más estudiados y maximizar la extracción de potencia de la ola es el objetivo primordial de los últimos anos. Este trabajo avanza sobre una propuesta inicial de controladores de Modo Deslizante de Segundo Orden, considerando condiciones realistas de funcionamiento para el sistema y una configuración de ganancias adaptivas que reduce el chattering. Los resultados muestran notablemente la mejora esperada, a partir de reducir el esfuerzo de control, manteniendo la robustez ante incertidumbre en los parámetros, dinámica no modelada y perturbaciones
An unusual transmission event of Neisseria meningitidis serogroup W135 type 2a in a healthcare setting, England, 2012.
The practical management of chronic pancreatitis:A Multidisciplinary Symposium Held at the Annual Meeting of the Pancreatic Society of Great Britain and Ireland, Manchester 2016
Aim: This study is about a questionnaire survey of delegates attending the chronic pancreatitis symposium at the 2016 meeting of the Pancreatic Society of Great Britain and Ireland and seeks a multidisciplinary “snapshot” overview of practice. Methods: A questionnaire was developed with multidisciplinary input. Questions on access to specialist care, methods of diagnosis and treatment including specific scenarios were incorporated. Eighty-three (66%) of 125 delegates effectively participated in this survey. Results: Twenty-four (29%) had neither a chronic pancreatitis MDT in their hospital nor a chronic pancreatitis referral MDT. Most frequently utilised diagnostic modalities were CT, MR and EUS with no respondents utilising duodenal intubation tests. Initial treatment was provided through non-opiate analgesia by 69 (93%), through the use of opiates by 56 (76%) and through the use of co-analgesics by 49 (66%). Fifty two (68%) routinely referred patients with alcohol-related disease for counselling. Preferred treatment for large duct disease without mass was endoscopic therapy. In older patients with a mass, pancreaticoduodenectomy was preferred. Conclusion: This is a small study likely to be skewed by sampling bias but is thought to be the first multidisciplinary survey of the management of chronic pancreatitis in the United Kingdom and Ireland. The results show a need for comprehensive access to specialist pancreatitis MDT care and there remains substantial variation in management
The relationship between chiropractor required and current level of business knowledge
Background: Chiropractors frequently practice within health care systems requiring the business acumen of an entrepreneur. However, some chiropractors do not know the relationship between the level of business knowledge required for practice success and their current level of business knowledge. The purpose of this quantitative study was to examine the relationship between chiropractors’ perceived level of business knowledge required and their perceived level of current business knowledge. Methods: Two hundred and seventy-four participants completed an online survey (Health Care Training and Education Needs Survey) which included eight key business items. Participants rated the level of perceived business knowledge required (Part I) and their current perceived level of knowledge (Part II) for the same eight items. Data was collected from November 27, 2013 to December 18, 2013. Data were analyzed using Spearman’s ranked correlation to determine the statistically significant relationships for the perceived level of knowledge required and the perceived current level of knowledge for each of the paired eight items from Parts I and II of the survey. Wilcoxon Signed Ranks Tests were performed to determine the statistical difference between the paired items. Results: The results of Spearman’s correlation testing indicated a statistically significant (p < 0.01) positive correlation for the perceived level of knowledge required and perceived current level of knowledge for six variables: (a) organizational behavior, (b) strategic management, (c) marketing, (d) legal and ethical, (e) managerial decisions, and (f) operations. Wilcoxon Signed Ranks testing indicated a significant difference for three paired items: strategic management; marketing and; legal and ethical. The results suggest that relationships exist for the majority of business items (6 of 8) however a statistically difference was demonstrated in only three of the paired business items. Conclusion: The implications of this study for social change include the potential to improve chiropractors’ business knowledge and skills, enable practice success, enhance health services delivery and positively influence the profession as a viable career.https://doi.org/10.1186/s12998-017-0134-
Public health professionals' perceptions toward provision of health protection in England: a survey of expectations of Primary Care Trusts and Health Protection Units in the delivery of health protection
BACKGROUND: Effective health protection requires systematised responses with clear accountabilities. In England, Primary Care Trusts and the Health Protection Agency both have statutory responsibilities for health protection. A Memorandum of Understanding identifies responsibilities of both parties, but there is a potential lack of clarity about responsibility for specific health protection functions. We aimed to investigate professionals' perceptions of responsibility for different health protection functions, to inform future guidance for, and organisation of, health protection in England. METHODS: We sent a postal questionnaire to all health protection professionals in England from the following groups: (a) Directors of Public Health in Primary Care Trusts; (b) Directors of Health Protection Units within the Health Protection Agency; (c) Directors of Public Health in Strategic Health Authorities and; (d) Regional Directors of the Health Protection Agency RESULTS: The response rate exceeded 70%. Variations in perceptions of who should be, and who is, delivering health protection functions were observed within, and between, the professional groups (a)-(d). Concordance in views of which organisation should, and which does deliver was high (≥90%) for 6 of 18 health protection functions, but much lower (≤80%) for 6 other functions, including managing the implications of a case of meningitis out of hours, of landfill environmental contamination, vaccination in response to mumps outbreaks, nursing home infection control, monitoring sexually transmitted infections and immunisation training for primary care staff. The proportion of respondents reporting that they felt confident most or all of the time in the safe delivery of a health protection function was strongly correlated with the concordance (r = 0.65, P = 0.0038). CONCLUSION: Whilst we studied professionals' perceptions, rather than actual responses to incidents, our study suggests that there are important areas of health protection where consistent understanding of responsibility for delivery is lacking. There are opportunities to clarify the responsibility for health protection in England, perhaps learning from the approaches used for those health protection functions where we found consistent perceptions of accountability
Mapping autophagosome contents identifies interleukin-7 receptor-α as a key cargo modulating CD4+ T cell proliferation
CD4+ T cells are pivotal cells playing roles in the orchestration of humoral and cytotoxic immune responses. It is known that CD4+ T cell proliferation relies on autophagy, but identification of the autophagosomal cargo involved is missing. Here we create a transgenic mouse model, to enable direct mapping of the proteinaceous content of autophagosomes in primary cells by LC3 proximity labelling. Interleukin-7 receptor-α, a cytokine receptor mostly found in naïve and memory T cells, is reproducibly detected in autophagosomes of activated CD4+ T cells. Consistently, CD4+ T cells lacking autophagy show increased interleukin-7 receptor-α surface expression, while no defect in internalisation is observed. Mechanistically, excessive surface interleukin-7 receptor-α sequestrates the common gamma chain, impairing the interleukin-2 receptor assembly and downstream signalling crucial for T cell proliferation. This study shows that key autophagy substrates can be reliably identified in this mouse model and help mechanistically unravel autophagy's contribution to healthy physiology and disease
Polyamines and eIF5A Hypusination Modulate Mitochondrial Respiration and Macrophage Activation
How cells adapt metabolism to meet demands is an active area of interest across biology. Among a broad range of functions, the polyamine spermidine is needed to hypusinate the translation factor eukaryotic initiation factor 5A (eIF5A). We show here that hypusinated eIF5A (eIF5AH) promotes the efficient expression of a subset of mitochondrial proteins involved in the TCA cycle and oxidative phosphorylation (OXPHOS). Several of these proteins have mitochondrial targeting sequences (MTSs) that in part confer an increased dependency on eIF5AH. In macrophages, metabolic switching between OXPHOS and glycolysis supports divergent functional fates stimulated by activation signals. In these cells, hypusination of eIF5A appears to be dynamically regulated after activation. Using in vivo and in vitro models, we show that acute inhibition of this pathway blunts OXPHOS-dependent alternative activation, while leaving aerobic glycolysis-dependent classical activation intact. These results might have implications for therapeutically controlling macrophage activation by targeting the polyamine-eIF5A-hypusine axis
A Methodological Framework for the Evaluation of Syndromic Surveillance Systems: A Case Study of England
Background: Syndromic surveillance complements traditional public health surveillance by collecting and analysing health indicators in near real time. The rationale of syndromic surveillance is that it may detect health threats faster than traditional surveillance systems permitting more timely, and hence potentially more effective public health action. The effectiveness of syndromic surveillance largely relies on the methods used to detect aberrations. Very few studies have evaluated the performance of syndromic surveillance systems and consequently little is known about the types of events that such systems can and cannot detect. Methods: We introduce a framework for the evaluation of syndromic surveillance systems that can be used in any setting based upon the use of simulated scenarios. For a range of scenarios this allows the time and probability of to be determined and uncertainty is fully incorporated. In addition, we demonstrate how such a framework can model the benefits of increases in the number of centres reporting syndromic data and also determine the minimum size of outbreaks that can or cannot be detected. Here, we demonstrate its utility using simulations of national influenza outbreaks and localised outbreaks of cryptosporidiosis. Results: Influenza outbreaks are consistently detected with larger outbreaks being detected in a more timely manner. Small cryptosporidiosis outbreaks (<1000 symptomatic individuals) are unlikely to be detected. We also demonstrate the advantages of having multiple syndromic data streams (e.g. emergency attendance data, telephone helpline data, general practice consultation data) as different streams are able to detect different types outbreaks with different efficacy (e.g. emergency attendance data are useful for the detection of pandemic influenza but not for outbreaks of cryptosporidiosis). We also highlight that for any one disease, the utility of data streams may vary geographically, and that the detection ability of syndromic surveillance varies seasonally (e.g. an influenza outbreak starting in July is detected sooner than one starting later in the year). We argue that our framework constitutes a useful tool for public health emergency preparedness in multiple settings. Conclusions: The proposed framework allows the exhaustive evaluation of any syndromic surveillance system and constitutes a useful tool for emergency preparedness and response
Adhesion Molecules Associated with Female Genital Tract Infection
Altres ajuts: Marie Curie Career Integration Grant i una beca Fundació Dexeus Salut de la DonaEfforts to develop vaccines that can elicit mucosal immune responses in the female genital tract against sexually transmitted infections have been hampered by an inability to measure immune responses in these tissues. The differential expression of adhesion molecules is known to confer site-dependent homing of circulating effector T cells to mucosal tissues. Specific homing molecules have been defined that can be measured in blood as surrogate markers of local immunity (e.g. α4β7 for gut). Here we analyzed the expression pattern of adhesion molecules by circulating effector T cells following mucosal infection of the female genital tract in mice and during a symptomatic episode of vaginosis in women. While CCR2, CCR5, CXCR6 and CD11c were preferentially expressed in a mouse model of Chlamydia infection, only CCR5 and CD11c were clearly expressed by effector T cells during bacterial vaginosis in women. Other homing molecules previously suggested as required for homing to the genital mucosa such as α4β1 and α4β7 were also differentially expressed in these patients. However, CD11c expression, an integrin chain rarely analyzed in the context of T cell immunity, was the most consistently elevated in all activated effector CD8+ T cell subsets analyzed. This molecule was also induced after systemic infection in mice, suggesting that CD11c is not exclusive of genital tract infection. Still, its increase in response to genital tract disorders may represent a novel surrogate marker of mucosal immunity in women, and warrants further exploration for diagnostic and therapeutic purposes
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