151 research outputs found
Isentropic Analysis of Convective Motions
This paper analyzes the convective mass transport by sorting air parcels in terms of their equivalent potential temperature to determine an isentropic streamfunction. By averaging the vertical mass flux at a constant value of the equivalent potential temperature, one can compute an isentropic mass transport that filters out reversible oscillatory motions such as gravity waves. This novel approach emphasizes the fact that the vertical energy and entropy transports by convection are due to the combination of ascending air parcels with high energy and entropy and subsiding air parcels with lower energy and entropy. Such conditional averaging can be extended to other dynamic and thermodynamic variables such as vertical velocity, temperature, or relative humidity to obtain a comprehensive description of convective motions. It is also shown how this approach can be used to determine the mean diabatic tendencies from the three-dimensional dynamic and thermodynamic fields. A two-stream approximation that partitions the isentropic circulation into a mean updraft and a mean downdraft is also introduced. This offers a straightforward way to identify the mean properties of rising and subsiding air parcels. The results from the two-stream approximation are compared with two other definitions of the cloud mass flux. It is argued that the isentropic analysis offers a robust definition of the convective mass transport that is not tainted by the need to arbitrarily distinguish between convection and its environment, and that separates the irreversible convective overturning fromoscillations associated with gravity waves
Stockage souterrain des eaux pluviales dans des conduites circulaires avec un réducteur de débit, pour une utilisation en sites urbains denses
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Feasibility and acceptability of an intervention for enhancing reintegration in adults with experience of homelessness.
Background: Service centres for homeless adults are potential settings for implementation of reintegration interventions. This study aimed to evaluate 1) the acceptability of a group-based programme among individuals from the broad population of homeless people, and 2) if a future study of its feasibility and acceptability for re-housed homeless people is warranted.
Method: Recruiting participants and intervention facilitators from partnering service centres was thought to improve recruitment and retention, cost-effectiveness, and social interactions compared to professional-led interventions. Seven adults with experience of homelessness (3 females, 4 males, mean age 39 years, range 18-63) were recruited to participate in the intervention. The research protocol comprised completion pre/post of scales (Recovering Quality of Life questionnaire; Working Alliance Inventory-short form revised, WAI-SR) and focus groups, and WAI-SR and focus groups after sessions 3 and 6.
Results: The intervention and research protocols were feasible, with all participants engaging in all sessions, completing all scales and attending all focus groups. The quantitative data demonstrated the feasibility of obtaining practically useful measures of relevant outcomes. In the 4 focus groups, the intervention received very favourable feedback.
Conclusions: This study demonstrated initial feasibility and acceptability of an intervention that places minimal burden on infrastructure and promotes user autonomy. This is an important advance as there is increasing recognition that the challenge of reintegration is as much a psychological and social problem as a housing problem. If effective, this style of intervention may serve as a template for future interventions with similar populations
Cognitive disorders in patients with chronic kidney disease: specificities of clinical assessment
Neurocognitive disorders are frequent among chronic kidney disease (CKD) patients. Identifying and characterizing cognitive impairment (CI) can help to assess the ability of adherence to CKD risk reduction strategy, identify potentially reversible causes of cognitive decline, modify pharmacotherapy, educate the patient and caregiver and provide appropriate patient and caregiver support. Numerous factors are associated with the development and progression of CI in CKD patients and various conditions can influence the results of cognitive assessment in these patients. Here we review clinical warning signs that should lead to cognitive screening; conditions frequent in CKD at risk to interfere with cognitive testing or performance, including specificities of cognitive assessment in dialysis patients or after kidney transplantation; and available tests for screening and observed cognitive patterns in CKD patients
A high concentration of TGF-β correlates with opportunistic infection in liver and kidney transplantation
Transforming growth factor-β (TGF-β) has been associated with numerous human infections, but its role in the occurrence of opportunistic infection (OI) after solid organ transplantation remains unexplored. This study aimed to assess the utility of the TGF-β following in vitro stimulation of whole peripheral blood (WPB) as a surrogate biomarker of post-transplant OI in a cohort of liver and kidney recipients. Thirty liver and thirty-one kidney transplant recipients were recruited to be prospectively monitored for one-year post-transplantation. Enzyme-linked immunosorbent assay (ELISA) was performed to calculate IFN-γ, IL-17, IL-10 and TGF-β concentration in the supernatant from the activated WPB. Recipients showed higher TGF-β concentrations compared to IFN-γ, IL-17, IL-10 at baseline, although these differences were not significant between INF and NoINF. However, recipients who developed an OI within the first sixth months had a higher concentration of TGF-β than those without OI. A concentration of TGF-β > 363.25 pg/ml in liver and TGF-β > 808.51 pg/ml in kidney recipients were able to stratify patients at high risk of OI with a sensitivity and specificity above 70% in both types of solid organ transplantations. TGF-β could provide valuable information for the management of liver and kidney recipients at risk of post-transplant infection.Our work was possible thanks to the support and funding obtained from the “Instituto de Salud Carlos III (ISCIII)”, Spanish Ministry of Health (Grant Number PI15/01370 and P19/01194); and co-funding by the European Union from the European Regional Development Fund (ERDF) with the principle of “A manner to build Europe”
Cognitive disorders in patients with chronic kidney disease:Approaches to prevention and treatment
Background: Cognitive impairment is common in patients with chronic kidney disease (CKD), and early intervention may prevent the progression of this condition. Methods: Here, we review interventions for the complications of CKD (anemia, secondary hyperparathyroidism, metabolic acidosis, harmful effects of dialysis, the accumulation of uremic toxins) and for prevention of vascular events, interventions that may potentially be protective against cognitive impairment. Furthermore, we discuss nonpharmacological and pharmacological methods to prevent cognitive impairment and/or minimize the latter's impact on CKD patients' daily lives. Results: A particular attention on kidney function assessment is suggested during work-up for cognitive impairment. Different approaches are promising to reduce cognitive burden in patients with CKD but the availabe dedicated data are scarce. Conclusions: There is a need for studies assessing the effect of interventions on the cognitive function of patients with CKD.</p
IL-6-174 G/C and -572 C/G Polymorphisms and Risk of Alzheimer’s Disease
Associations between interleukin 6 (IL-6) polymorphisms and Alzheimer’s disease (AD) remain controversial and ambiguous. The aim of this meta-analysis is to explore more precise estimations for the relationship between IL-6-174 G/C and -572 C/G polymorphisms and risk for AD. Electronic searches for all publications in databases PubMed and EMBASE were conducted on the associations between IL-6 polymorphisms and risk for AD until January 2012. Odds ratio (OR) and 95% confidence intervals (CIs) were calculated using fixed and random effects models. Twenty-seven studies were included with a total of 19,135 individuals, involving 6,632 AD patients and 12,503 controls. For IL-6-174 G/C polymorphism, the combined results showed significant differences in recessive model (CC vs. CG+GG: OR = 0.65, 95%CI = 0.52–0.82). As regards IL-6-572 C/G polymorphism, significant associations were shown in dominant model (CG+GG vs. CC: OR = 0.73, 95% CI = 0.62–0.86) and in additive model (GG vs. CC, OR = 0.66, 95% CI = 0.46–0.96). In conclusion, genotype CC of IL-6-174 G/C and genotype GG plus GC of IL-6-572 C/G could decrease the risk of AD
Cognitive disorders in patients with chronic kidney disease: specificities of clinical assessment
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Precursor lesions of early onset pancreatic cancer
Early onset pancreatic cancer (EOPC) constitutes less than 5% of all newly diagnosed cases of pancreatic cancer (PC). Although histopathological characteristics of EOPC have been described, no detailed reports on precursor lesions of EOPC are available. In the present study, we aimed to describe histopathological picture of extratumoral parenchyma in 23 cases of EOPCs (definition based on the threshold value of 45 years of age) with particular emphasis on two types of precursor lesions of PC: pancreatic intraepithelial neoplasia (PanIN) and intraductal papillary mucinous neoplasms (IPMNs). The types, grades, and densities of precursor lesions of PC were compared in patients with EOPCs, in young patients with neuroendocrine neoplasms (NENs), and in older (at the age of 46 or more) patients with PC. PanINs were found in 95.6% of cases of EOPCs. PanINs-3 were found in 39.1% of EOPC cases. Densities of all PanIN grades in EOPC cases were larger than in young patients with NENs. Density of PanINs-1A in EOPC cases was larger than in older patients with PC, but densities of PanINs of other grades were comparable. IPMN was found only in a single patient with EOPC but in 20% of older patients with PC. PanINs are the most prevalent precursor lesions of EOPC. IPMNs are rarely precursor lesions of EOPC. Relatively high density of low-grade PanINs-1 in extratumoral parenchyma of patients with EOPC may result from unknown multifocal genetic alterations in pancreatic tissue in patients with EOPCs
Cognitive disorders in patients with chronic kidney disease: Approaches to prevention and treatment
Background: Cognitive impairment is common in patients with chronic kidney disease (CKD), and early intervention may prevent the progression of this condition. Methods: Here, we review interventions for the complications of CKD (anemia, secondary hyperparathyroidism, metabolic acidosis, harmful effects of dialysis, the accumulation of uremic toxins) and for prevention of vascular events, interventions that may potentially be protective against cognitive impairment. Furthermore, we discuss nonpharmacological and pharmacological methods to prevent cognitive impairment and/or minimize the latter's impact on CKD patients' daily lives. Results: A particular attention on kidney function assessment is suggested during work-up for cognitive impairment. Different approaches are promising to reduce cognitive burden in patients with CKD but the availabe dedicated data are scarce. Conclusions: There is a need for studies assessing the effect of interventions on the cognitive function of patients with CKD
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