163 research outputs found
Tidal energy "Round Robin" tests - comparisons between towing tank and circulating tank results
The key step of the industrial development of tidal energy is testing the turbine in a controlled environment. At present, there is no available experimental protocol which address the differences between the facilities currently employed for this type of technology in a quantitative manner. It has been difficult to compare the results obtained in the different facilities, therefore there has only been sensitive comparisons of their efficiency. In order to evaluate the ability of different experimental facilities, a comparative "Round Robin" testing programme has been conducted by MaRINET. The aim of the trials was to test the tidal turbine model in four different test facilities. The results obtained in each facilities showed a near identical key performance. The expected differences appeared in the fluctuations of torque and drag measurements between the different tank designs (circulating and towing). The main facility parameters which can influence the behaviour of the turbine were identified
Dyslipidemia and chronic inflammation markers are correlated with telomere length shortening in Cushing's syndrome
INTRODUCTION: Cushing's syndrome (CS) increases cardiovascular risk (CVR) and adipocytokine imbalance, associated with an increased inflammatory state. Telomere length (TL) shortening is a novel CVR marker, associated with inflammation biomarkers. We hypothesized that inflammatory state and higher CVR in CS might be related to TL shortening, as observed in premature aging. - AIM: to evaluate relationships between TL, CVR and inflammation markers in CS. - METHODS: in a cross-sectional study, 77 patients with CS (14 males, 59 pituitary-, 17 adrenal- and 1 ectopic-origin; 21 active disease) and 77 age-, gender-, smoking-matched controls were included. Total white blood cell TL was measured by TRF-Southern technique. Clinical data and blood samples were collected (lipids, adrenal function, glucose). Adiponectin, interleukin-6 (IL6) and C-reactive protein (CRP) were available in a subgroup of patients (n=32). Correlations between TL and clinical features were examined and multiple linear regression analysis was performed to investigate potential predictors of TL. - RESULTS: dyslipidemic CS had shorter TL than non-dyslipidemic subjects (7328±1274 vs 7957±1137 bp, p<0.05). After adjustment for age and body mass index, cured and active CS dyslipidemic patients had shorter TL than non-dyslipidemic CS (cured: 7187±1309 vs 7868±1104; active: 7203±1262 vs 8615±1056, respectively, p<0.05). Total cholesterol and triglycerides negatively correlated with TL (r-0.279 and -0.259, respectively, p<0.05), as well as CRP and IL6 (r-0.412 and -0.441, respectively, p<0.05). No difference in TL according the presence of other individual CVR factors (hypertension, diabetes mellitus, obesity) were observed in CS or in the control group. Additional TL shortening was observed in dyslipidemic obese patients who were also hypertensive, compared to those with two or less CVR factors (6956±1280 vs 7860±1180, respectively, p<0.001). Age and dyslipidemia were independent negative predictors of TL. -CONCLUSION :TL is shortened in dyslipidemic CS patients, further worse if hypertension and/or obesity coexist and is negatively correlated with increased inflammation markers. Increased lipids and a "low" grade inflammation may contribute to TL shortening and consequently to premature ageing and increased morbidity in CS
Colouration in amphibians as a reflection of nutritional status : the case of tree frogs in Costa Rica
Colouration has been considered a cue for mating success in many species; ornaments in males often are related to carotenoid mobilization towards feathers and/or skin and can signal general health and nutrition status. However, there are several factors that can also link with status, such as physiological blood parameters and body condition, but there is not substantial evidence which supports the existence of these relationships and interactions in anurans. This study evaluated how body score and blood values interact with colouration in free-range Agalychnis callidryas and Agalychnis annae males. We found significant associations between body condition and plasmatic proteins and haematocrit, as well as between body condition and colour values from the chromaticity diagram. We also demonstrated that there is a significant relation between the glucose and plasmatic protein values that were reflected in the ventral colours of the animals, and haematocrit inversely affected most of those colour values. Significant differences were found between species as well as between populations of A. callidryas, suggesting that despite colour variation, there are also biochemical differences within animals from the same species located in different regions. These data provide information on underlying factors for colouration of male tree frogs in nature, provide insights about the dynamics of several nutrients in the amphibian model and how this could affect the reproductive output of the animals
Body composition after endogenous (Cushing's syndrome) and exogenous (rheumatoid arthritis) exposure to glucocorticoids
Exposure to chronic glucocorticoid (GC) excess determines changes in body composition. The aim of the study was to compare body composition in women exposed to endogenous hypercortisolism (Cushing's syndrome, CS), exogenous glucocorticoid treatment (rheumatoid arthritis, RA) and controls. Fifty-one CS women, 26 RA women treated with low-dose prednisone (5 mg/day or 10 mg/2 days), and 78 female controls were included. Fourteen CS patients were hypercortisolemic, 37 in remission (10 required hydrocortisone substitution after surgery). Body composition parameters were measured by dual-energy X-ray absorptiometry scanning (DEXA). RA patients had a greater waist-hip ratio (WHR) (p<0.01), less lean body mass (LBM) (p<0.01), and lumbar bone mineral density (BMD) (p<0.01) than controls. CS patients, globally and those with cured disease, had more total fat (both percentage and kg) and trunk fat percentage, and less whole body-BMD than RA patients (p<0.05, p<0.01, p<0.05, respectively). Active CS patients had less whole body-BMD and more LBM than RA patients (p<0.05, p=0.01, respectively). Cured CS patients not taking hydrocortisone had more total fat [both percentage (p<0.05) and kg (p<0.05)], trunk fat percentage (p<0.05), lumbar BMD (p<0.01) than RA patients. Cured CS patients requiring hydrocortisone only differed from RA patients by smaller WHR (p<0.01). All the differences in BMD disappeared when the data were reanalyzed including only the estrogen-deficient groups. Hypercortisoliof CS determines an irreversible increase in body fat, greater than in RA. Endogenous and exogenous exposure to GC negatively affects body composition by increasing the WHR. There appears to be no additional effect on BMD in estrogen-deficient women
Factores de riesgo cardiovascular entre pacientes con sÃndrome de Cushing, curados y no curados con respecto a un grupo control
Objetivos: Describir los factores de riesgo cardiovascular que se presentan en el paciente con SÃndrome de Cushing (SC), para establecer programas educativos adaptados a este grupo de pacientes. Método: El ámbito de estudio se desarrolló en el Hospital de Sant Pau, en el Servicio de EndocrinologÃa. Se extrajeron datos de las Historias ClÃnicas de los pacientes que fueron visitados en consultas con diagnóstico de SC en el 2005, realizándose una recogida retrospectiva. No se excluyó ningún paciente, independientemente de los años de duración de la patologÃa, de las opciones terapéuticas o del tratamiento farmacológico recibido, incluyendo todos los pacientes con SC. Elaboramos una hoja de recogida de datos demográficos, clÃnicos (peso, Ãndice de masa corporal, tensión arterial, perÃmetro abdominal) y analÃticos (lÃpidos, glicemia); para el tratamiento informático se utilizó el programa SPSS. Resultados: El perÃmetro abdominal fue mayor en pacientes no curados (100.8 ±13.9cm) que en controles (89±12.8cm) (p<0.05). Respecto al peso no se encontraron diferencias significativas entre controles (69,9±13,3Kg), curados (69,9±16,5Kg) y no curados (76,4±16,5Kg). El IMC tampoco reflejó diferencias en los tres grupos en estudio: control (26,5±5,2), curados (27,8±6,4) y no curados (29,3±3,8). El colesterol fue más alto en los pacientes curados (5.90±0.92mmol/L) que en controles (5.38±1.07mmol/L) (p<0.05), al igual que los triglicéridos (1.20±0.51mmol/L versus controles 1.05±0.56mmol/L; p<0.05). Ambos grupos de pacientes presentaron presión sistólica mayor que los controles (curados,128.3±16.7mmHg p<0.05; no curados,134.1±13mmHg, p<0.001). Los no curados (78.6±9.2mmHg) presentaron además presión diastólica mayor que los controles (72.3±8.6, p<0.05) Fig.3. No observamos diferencias en la glicemia basal entre los 3 grupos de pacientes. Conclusiones: Los pacientes con SC, curados de su hipercortisolismo y con enfermedad activa presentan mayor riesgo cardiovascular y metabólico, comparados con el grupo control. La enfermera educadora deberá contemplar e incluir en los programas de prevención secundaria a dichos pacientes, para promocionar hábitos saludables, prevenir y controlar sus factores de riesgo. Palabras Clave SÃndrome Cushing, educación sanitaria, factores de riesgo cardiovascular
2012 Activity Report of the Regional Research Programme on Hadrontherapy for the ETOILE Center
2012 is the penultimate year of financial support by the CPER 2007-2013 for ETOILE's research program, sustained by the PRRH at the University Claude Bernard. As with each edition we make the annual review of the research in this group, so active for over 12 years now. Over the difficulties in the decision-making process for the implementation of the ETOILE Center, towards which all our efforts are focussed, some "themes" (work packages) were strengthened, others have progressed, or have been dropped. This is the case of the eighth theme (technological developments), centered around the technology for rotative beam distribution heads (gantries) and, after being synchronized with the developments of ULICE's WP6, remained so by ceasing its activities, coinciding also with the retirement of its historic leader at IPNL, Marcel Bajard. Topic number 5 ("In silico simulations") has suffered the departure of its leader, Benjamin Ribba, although the work has still been provided by Branka Bernard, a former postdoctoral fellow in Lyon Sud, and now back home in Croatia, still in contract with UCBL for the ULICE project. Aside from these two issues (and the fact that the theme "Medico-economical simulations" is now directly linked to the first one ("Medical Project"), the rest of the teams are growing, as evidenced by the publication statistics at the beginning of this report. This is obviously due to the financial support of our always faithful regional institutions, but also to the synergy that the previous years, the European projects, the arrival of the PRIMES LabEx, and the national France Hadron infrastructure have managed to impulse. The Rhone-Alpes hadron team, which naturally includes the researchers of LPC at Clermont, should also see its influence result in a strong presence in France Hadron's regional node, which is being organized. The future of this regional research is not yet fully guaranteed, especially in the still uncertain context of ETOILE, but the tracks are beginning to emerge to allow past and present efforts translate into a long future that we all want to see established. Each of the researchers in PRRH is aware that 2013 will be (and already is) the year of great challenge : for ETOILE, for the PRRH, for hadron therapy in France, for French hadrontherapy in Europe (after the opening and beginning of treatments in the German [HIT Heidelberg, Marburg], Italian [CNAO, Pavia] and Austrian [MedAustron, Wien Neuerstadt]) centers. Let us meet again in early 2014 for a comprehensive review of the past and a perspective for the future ..
Telomere length analysis in Cushing's syndrome
Introduction: Hypercortisolism in Cushing's syndrome (CS) is associated with increased morbidity and mortality. Hypercortisolism also occurs in chronic depressive disorders and stress, where telomere length (TL) is shorter than in controls. We hypothesized that shortening of telomere might occur in CS and contribute to premature aging and morbidity. - Aim: To investigate TL in CS patients compared with controls. - Methods: Seventy-seven CS patients (14 males, 59 pituitary, 17 adrenal, and one ectopic; 21 with active disease) were compared with 77 gender-, age-, and smoking-matched controls. Fifteen CS were evaluated longitudinally, during active disease and after remission of hypercortisolism. Leukocyte TL was measured by telomere restriction fragment-Southern technique. Clinical markers were included in a multiple linear regression analysis to investigate potential predictors of TL. - Results : Mean TL in CS patients and controls was similar (7667 vs 7483 bp, NS). After adjustment for age, in the longitudinal evaluation, TL was shorter in active disease than after remission (7273 vs 7870, P<0.05). Age and dyslipidemia were negative predictors (P<0.05), and total leukocyte count was a positive predictor for TL (P<0.05). As expected, a negative correlation was found between TL and age (CS, R=−0.400 and controls, R=−0.292; P<0.05). No correlation was found between circulating cortisol, duration of exposure to hypercortisolism or biochemical cure and TL. - Conclusion : Even though in the cross-sectional comparison of CS and controls no difference in TL was found, in the longitudinal evaluation, patients with active CS had shorter TL than after biochemical cure of hypercortisolism. These preliminary results suggest that hypercortisolism might negatively impact telomere maintenance. Larger studies are needed to confirm these findings
Temperature and Resource Availability May Interactively Affect Over-Wintering Success of Juvenile Fish in a Changing Climate
The predicted global warming may affect freshwater systems at several organizational levels, from organism to ecosystem. Specifically, in temperate regions, the projected increase of winter temperatures may have important effects on the over-winter biology of a range of organisms and especially for fish and other ectothermic animals. However, temperature effects on organisms may be directed strongly by resource availability. Here, we investigated whether over-winter loss of biomass and lipid content of juvenile roach (Rutilus rutilus) was affected by the physiologically relatively small (2-5°C) changes of winter temperatures predicted by the Intergovernmental Panel on Climate Change (IPCC), under both natural and experimental conditions. This was investigated in combination with the effects of food availability. Finally, we explored the potential for a correlation between lake temperature and resource levels for planktivorous fish, i.e., zooplankton biomass, during five consecutive winters in a south Swedish lake. We show that small increases in temperature (+2°C) affected fish biomass loss in both presence and absence of food, but negatively and positively respectively. Temperature alone explained only a minor part of the variation when food availability was not taken into account. In contrast to other studies, lipid analyses of experimental fish suggest that critical somatic condition rather than critical lipid content determined starvation induced mortality. Our results illustrate the importance of considering not only changes in temperature when predicting organism response to climate change but also food-web interactions, such as resource availability and predation. However, as exemplified by our finding that zooplankton over-winter biomass in the lake was not related to over-winter temperature, this may not be a straightforward task
Global Perspectives on Task Shifting and Task Sharing in Neurosurgery.
BACKGROUND: Neurosurgical task shifting and task sharing (TS/S), delegating clinical care to non-neurosurgeons, is ongoing in many hospital systems in which neurosurgeons are scarce. Although TS/S can increase access to treatment, it remains highly controversial. This survey investigated perceptions of neurosurgical TS/S to elucidate whether it is a permissible temporary solution to the global workforce deficit. METHODS: The survey was distributed to a convenience sample of individuals providing neurosurgical care. A digital survey link was distributed through electronic mailing lists of continental neurosurgical societies and various collectives, conference announcements, and social media platforms (July 2018-January 2019). Data were analyzed by descriptive statistics and univariate regression of Likert Scale scores. RESULTS: Survey respondents represented 105 of 194 World Health Organization member countries (54.1%; 391 respondents, 162 from high-income countries and 229 from low- and middle-income countries [LMICs]). The most agreed on statement was that task sharing is preferred to task shifting. There was broad consensus that both task shifting and task sharing should require competency-based evaluation, standardized training endorsed by governing organizations, and maintenance of certification. When perspectives were stratified by income class, LMICs were significantly more likely to agree that task shifting is professionally disruptive to traditional training, task sharing should be a priority where human resources are scarce, and to call for additional TS/S regulation, such as certification and formal consultation with a neurosurgeon (in person or electronic/telemedicine). CONCLUSIONS: Both LMIC and high-income countries agreed that task sharing should be prioritized over task shifting and that additional recommendations and regulations could enhance care. These data invite future discussions on policy and training programs
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