893 resultados para multi-component and multi-site adsorption


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Traditionally, desertification research has focused on degradation assessments, whereas prevention and mitigation strategies have not sufficiently been emphasised, although the concept of sustainable land management (SLM) is increasingly being acknowledged. SLM strategies are interventions at the local to regional scale aiming at increasing productivity, protecting the natural resource base, and improving livelihoods. The global WOCAT initiative and its partners have developed harmonized frameworks to compile, evaluate and analyse the impact of SLM practices around the globe. Recent studies within the EU research project DESIRE developed a methodological framework that combines a collective learning and decision-making approach with use of best practices from the WOCAT database. In-depth assessment of 30 technologies and 8 approaches from 17 desertification sites enabled an evaluation of how SLM addresses prevalent dryland threats such as water scarcity, soil and vegetation degradation, low production, climate change, resource use conflicts and migration. Among the impacts attributed to the documented technologies, those mentioned most were diversified and enhanced production and better management of water and soil degradation, whether through water harvesting, improving soil moisture, or reducing runoff. Water harvesting offers under-exploited opportunities for the drylands and the predominantly rainfed farming systems of the developing world. Recently compiled guidelines introduce the concepts behind water harvesting and propose a harmonised classification system, followed by an assessment of suitability, adoption and up-scaling of practices. Case studies go from large-scale floodwater spreading that make alluvial plains cultivable, to systems that boost cereal production in small farms, as well as practices that collect and store water from household compounds. Once contextualized and set in appropriate institutional frameworks, they can form part of an overall adaptation strategy for land users. More field research is needed to reinforce expert assessments of SLM impacts and provide the necessary evidence-based rationale for investing in SLM. This includes developing methods to quantify and value ecosystem services, both on-site and off-site, and assess the resilience of SLM practices, as currently aimed at within the new EU CASCADE project.

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Intensity modulated radiation therapy (IMRT) is a technique that delivers a highly conformal dose distribution to a target volume while attempting to maximally spare the surrounding normal tissues. IMRT is a common treatment modality used for treating head and neck (H&N) cancers, and the presence of many critical structures in this region requires accurate treatment delivery. The Radiological Physics Center (RPC) acts as both a remote and on-site quality assurance agency that credentials institutions participating in clinical trials. To date, about 30% of all IMRT participants have failed the RPC’s remote audit using the IMRT H&N phantom. The purpose of this project is to evaluate possible causes of H&N IMRT delivery errors observed by the RPC, specifically IMRT treatment plan complexity and the use of improper dosimetry data from machines that were thought to be matched but in reality were not. Eight H&N IMRT plans with a range of complexity defined by total MU (1460-3466), number of segments (54-225), and modulation complexity scores (MCS) (0.181-0.609) were created in Pinnacle v.8m. These plans were delivered to the RPC’s H&N phantom on a single Varian Clinac. One of the IMRT plans (1851 MU, 88 segments, and MCS=0.469) was equivalent to the median H&N plan from 130 previous RPC H&N phantom irradiations. This average IMRT plan was also delivered on four matched Varian Clinac machines and the dose distribution calculated using a different 6MV beam model. Radiochromic film and TLD within the phantom were used to analyze the dose profiles and absolute doses, respectively. The measured and calculated were compared to evaluate the dosimetric accuracy. All deliveries met the RPC acceptance criteria of ±7% absolute dose difference and 4 mm distance-to-agreement (DTA). Additionally, gamma index analysis was performed for all deliveries using a ±7%/4mm and ±5%/3mm criteria. Increasing the treatment plan complexity by varying the MU, number of segments, or varying the MCS resulted in no clear trend toward an increase in dosimetric error determined by the absolute dose difference, DTA, or gamma index. Varying the delivery machines as well as the beam model (use of a Clinac 6EX 6MV beam model vs. Clinac 21EX 6MV model), also did not show any clear trend towards an increased dosimetric error using the same criteria indicated above.

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Background Working hour limitations and tight health care budgets have posed significant challenges to emergency surgical services. Since 1 January 2010, surgical interventions at Berne University Hospital between 23:00 and 08:00 h have been restricted to patients with an expected serious adverse outcome if not operated on within 6 h. This study was designed to assess the safety of this new policy that restricts nighttime appendectomies (AEs). Methods The patients that underwent AE from 1 January 2010 to 31 December 2011 (“2010-2011 group”) were compared retrospectively with patients that underwent AE before introduction of the new policy (1 January 2006–31 December 2009; “2006-2009 group”). Results Overall, 390 patients were analyzed. There were 255 patients in the 2006–2009 group and 135 patients in the 2010–2011 group. Patients’ demographics did not differ statistically between the two study groups; however, 45.9 % of the 2006–2009 group and 18.5 % of the 2010–2011 group were operated between 23:00 and 08:00 h (p < 0.001). The rates of appendiceal perforations and surgical site infections did not differ statistically between the 2006–2009 group and the 2010–2011 group (20 vs. 18.5 %, p = 0.725 and 2 vs. 0 %, p = 0.102). Additionally, no difference was found for the hospital length of stay (3.9 ± 7.4 vs. 3.4 ± 6.0 days, p = 0.586). However, the proportion of patients with an in-hospital delay of >12 h was significantly greater in the 2010–2011 group than in the 2006–2009 group [55.6 vs. 43.5 %, p = 0.024, odds ratio (95 % confidence interval 1.62 (1.1–2.47)]. Conclusions Restricting AEs from 23:00 to 08:00 h does not increase the perforation rates and occurrence of clinical outcomes. Therefore, these results suggest that appendicitis may be managed safely in a semielective manner.

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Ore-forming and geoenviromental systems commonly involve coupled fluid flowand chemical reaction processes. The advanced numerical methods and computational modeling have become indispensable tools for simulating such processes in recent years. This enables many hitherto unsolvable geoscience problems to be addressed using numerical methods and computational modeling approaches. For example, computational modeling has been successfully used to solve ore-forming and mine site contamination/remediation problems, in which fluid flow and geochemical processes play important roles in the controlling dynamic mechanisms. The main purpose of this paper is to present a generalized overview of: (1) the various classes and models associated with fluid flow/chemically reacting systems in order to highlight possible opportunities and developments for the future; (2) some more general issues that need attention in the development of computational models and codes for simulating ore-forming and geoenviromental systems; (3) the related progresses achieved on the geochemical modeling over the past 50 years or so; (4) the general methodology for modeling of oreforming and geoenvironmental systems; and (5) the future development directions associated with modeling of ore-forming and geoenviromental systems.

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BACKGROUND Facial appearance is important for normal psychosocial development in children with cleft lip and palate (CLP). There is conflicting evidence on how deficient maxillary growth may affect nasolabial esthetics. METHODS We retrospectively investigated nasolabial appearance in two groups, the Langenback (35 children; mean age 11.1 years; range: 7.9-13.6) and Vomerplasty (58 children; mean age 10.8 years; range: 7.8-14), who received unilateral CLP surgery by the same surgeon. The hard palate repair technique differed between the two groups. In the Langenback group, palatal bone on the non-cleft side only was left denuded, inducing scar formation and inhibiting maxillary growth. In the Vomerplasty group, a vomerplasty with tight closure of the soft tissues on the palate was applied. Thirteen lay judges rated nasolabial esthetics on photographs using a modified Asher-McDade's index. RESULTS Nasolabial esthetics in both groups was comparable (p > 0.1 for each nasolabial component). Inferior view was judged as the least esthetic component and demonstrated mean scores 3.18 (SD = 0.63) and 3.13 (SD = 0.47) in the Langenback and Vomerplasty groups, respectively. Mean scores for other components were from 2.52 (SD = 0.63) to 2.81 (SD = 0.62). Regression analysis showed that vomerplasty is related with slight improvement in the nasal profile only (coefficient B = -0.287; p = 0.043; R(2 ) = 0.096). CONCLUSIONS This study demonstrates that the use of vomerplasty instead of the Langenbeck technique is weakly associated with the nasolabial appearance among pre-adolescent patients with UCLP.

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Contracted flexor tendon leading to flexural deformity is a common congenital defect in cattle. Arthrogryposis is a congenital syndrome of persistent joint contracture that occurs frequently in Europe as a consequence of Schmallenberg virus infection of the dam. Spastic paresis has a hereditary component, and affected cattle should not be used for breeding purposes. The most common tendon avulsion involves the deep digital flexor tendon. Tendon disruptions may be successfully managed by tenorrhaphy and external coaptation or by external coaptation alone. Medical management alone is unlikely to be effective for purulent tenosynovitis.

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BackgroundThe aim of the present study was to evaluate the feasibility of using a telephone survey in gaining an understanding of the possible herd and management factors influencing the performance (i.e. safety and efficacy) of a vaccine against porcine circovirus type 2 (PCV2) in a large number of herds and to estimate customers¿ satisfaction.ResultsDatasets from 227 pig herds that currently applied or have applied a PCV2 vaccine were analysed. Since 1-, 2- and 3-site production systems were surveyed, the herds were allocated in one of two subsets, where only applicable variables out of 180 were analysed. Group 1 was comprised of herds with sows, suckling pigs and nursery pigs, whereas herds in Group 2 in all cases kept fattening pigs. Overall 14 variables evaluating the subjective satisfaction with one particular PCV2 vaccine were comingled to an abstract dependent variable for further models, which was characterized by a binary outcome from a cluster analysis: good/excellent satisfaction (green cluster) and moderate satisfaction (red cluster). The other 166 variables comprised information about diagnostics, vaccination, housing, management, were considered as independent variables. In Group 1, herds using the vaccine due to recognised PCV2 related health problems (wasting, mortality or porcine dermatitis and nephropathy syndrome) had a 2.4-fold increased chance (1/OR) of belonging to the green cluster. In the final model for Group 1, the diagnosis of diseases other than PCV2, the reason for vaccine administration being other than PCV2-associated diseases and using a single injection of iron had significant influence on allocating into the green cluster (P¿<¿0.05). In Group 2, only unchanged time or delay of time of vaccination influenced the satisfaction (P¿<¿0.05).ConclusionThe methodology and statistical approach used in this study were feasible to scientifically assess ¿satisfaction¿, and to determine factors influencing farmers¿ and vets¿ opinion about the safety and efficacy of a new vaccine.

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BACKGROUND: Clinical disorders often share common symptoms and aetiological factors. Bifactor models acknowledge the role of an underlying general distress component and more specific sub-domains of psychopathology which specify the unique components of disorders over and above a general factor. METHODS: A bifactor model jointly calibrated data on subjective distress from The Mood and Feelings Questionnaire and the Revised Children's Manifest Anxiety Scale. The bifactor model encompassed a general distress factor, and specific factors for (a) hopelessness-suicidal ideation, (b) generalised worrying and (c) restlessness-fatigue at age 14 which were related to lifetime clinical diagnoses established by interviews at ages 14 (concurrent validity) and current diagnoses at 17 years (predictive validity) in a British population sample of 1159 adolescents. RESULTS: Diagnostic interviews confirmed the validity of a symptom-level bifactor model. The underlying general distress factor was a powerful but non-specific predictor of affective, anxiety and behaviour disorders. The specific factors for hopelessness-suicidal ideation and generalised worrying contributed to predictive specificity. Hopelessness-suicidal ideation predicted concurrent and future affective disorder; generalised worrying predicted concurrent and future anxiety, specifically concurrent generalised anxiety disorders. Generalised worrying was negatively associated with behaviour disorders. LIMITATIONS: The analyses of gender differences and the prediction of specific disorders was limited due to a low frequency of disorders other than depression. CONCLUSIONS: The bifactor model was able to differentiate concurrent and predict future clinical diagnoses. This can inform the development of targeted as well as non-specific interventions for prevention and treatment of different disorders.

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BACKGROUND: The role of laparoscopy in the setting of perforated appendicitis remains controversial. A retrospective study was conducted to evaluate the early postoperative outcomes of laparoscopic appendectomy (LA) compared to open appendectomy (OA) in patients with perforated appendicitis. METHODS: A total of 1,032 patients required an appendectomy between January 2005 and December 2009. Among these patients, 169 presented with perforated appendicitis. Operation times, length of hospital stay, overall complication rates within 30 days, and surgical site infection (SSI) rates were analyzed. RESULTS: Out of the 169 evaluated patients, 106 required LA and 63 OA. Although operation times were similar in both groups (92 ± 31 min for LA vs. 98 ± 45 for OA, p = 0.338), length of hospital stay was shorter in the LA group (6.9 ± 3.8 days vs. 11.5 ± 9.2, p < 0.001). Overall complication rates were significantly lower in the LA group (32.1 vs. 52.4 %, p < 0.001), as were incisional SSI (1.9 vs. 22.2 %, p < 0.001). Organ/space SSI rates were similar in both groups (23.6 % after LA vs. 20.6 % after OA, p = 0.657). CONCLUSIONS: For perforated appendicitis, LA results in a significantly shorter hospital stay, fewer overall postoperative complications, and fewer wound infections compared to OA. Organ/space SSI rates were similar for both procedures. LA provides a safe option for treating patients with perforated appendicitis.

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The T2K experiment has reported the first observation of the appearance of electron neutrinos in a muon neutrino beam. The main and irreducible background to the appearance signal comes from the presence in the neutrino beam of a small intrinsic component of electron neutrinos originating from muon and kaon decays. In T2K, this component is expected to represent 1.2% of the total neutrino flux. A measurement of this component using the near detector (ND280), located 280 m from the target, is presented. The charged current interactions of electron neutrinos are selected by combining the particle identification capabilities of both the time projection chambers and electromagnetic calorimeters of ND280. The measured ratio between the observed electron neutrino beam component and the prediction is 1.01±0.10 providing a direct confirmation of the neutrino fluxes and neutrino cross section modeling used for T2K neutrino oscillation analyses. Electron neutrinos coming from muons and kaons decay are also separately measured, resulting in a ratio with respect to the prediction of 0.68±0.30 and 1.10±0.14 , respectively.

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Eph receptors and their ligands (ephrins) play an important role in axonal guidance, topographic mapping, and angiogenesis. The signaling pathways mediating these activities are starting to emerge and are highly cell- and receptor-type specific. Here we demonstrate that activated EphB1 recruits the adaptor proteins Grb2 and p52Shc and promotes p52Shc and c-Src tyrosine phosphorylation as well as MAPK/extracellular signal-regulated kinase (ERK) activation. EphB1-mediated increase of cell migration was abrogated by the MEK inhibitor PD98059 and Src inhibitor PP2. In contrast, cell adhesion, which we previously showed to be c-jun NH2-terminal kinase (JNK) dependent, was unaffected by ERK1/2 and Src inhibition. Expression of dominant-negative c-Src significantly reduced EphB1-dependent ERK1/2 activation and chemotaxis. Site-directed mutagenesis experiments demonstrate that tyrosines 600 and 778 of EphB1 are required for its interaction with c-Src and p52Shc. Furthermore, phosphorylation of p52Shc by c-Src is essential for its recruitment to EphB1 signaling complexes through its phosphotyrosine binding domain. Together these findings highlight a new aspect of EphB1 signaling, whereby the concerted action of c-Src and p52Shc activates MAPK/ERK and regulates events involved in cell motility.

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Regular physical activity beneficially impacts the risk of onset and progression of several chronic diseases. However, research regarding the effects of exercising on chronic liver diseases is relatively recent. Most authors focused on non-alcoholic fatty liver disease (NAFLD), in which increasing clinical and experimental data indicate that skeletal muscle cross-talking to the adipose tissue and the liver regulates intrahepatic fat storage. In this setting physical activity is considered required in combination with calories restriction to allow an effective decrease of intrahepatic lipid component, and despite that evidence is not conclusive, some studies suggest that vigorous activity might be more beneficial than moderate activity to improve NAFLD/NASH. Evidence regarding the effects of exercise on the risk of hepatocellular carcinoma is scarce; some epidemiological studies indicate a lower risk in patients regularly and vigorously exercising. In compensated cirrhosis exercise acutely increases portal pressure, but in longer term it has been proved safe and probably beneficial. Decreased aerobic capacity (VO2) correlates with mortality in patients with decompensated cirrhosis, who are almost invariably sarcopenic. In these patients VO2 is improved by physical activity, which might also reduce the risk of hepatic encephalopathy through an increase in skeletal muscle mass. In solid organ transplantation recipients exercise is able to improve lean mass, muscle strength and as a consequence, aerobic capacity. Few data exist in liver transplant recipients, in whom exercise should be object of future studies given its high potential of providing long-term beneficial effects. Despite evidence is far from complete, physical activity should be seen as an important part of the management of patients with liver disease in order to improve their clinical outcome. This article is protected by copyright. All rights reserved.

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Background. A review of the literature suggests that Hypertension (HTN) in older adults is associated with sympathetic stimulation that results in increasing blood pressure (BP) reactivity. If clinical assessment of BP captured sympathetic stimulation, it would be valuable for hypertension management. ^ Objectives. The study examined whether reactive change scores from a short BPR protocol, resting blood pressure (BP), or resting pulse pressure (PP) is a better predictor of 24 hour ambulatory BP and BP load in cardiac patients. ^ Method. The study used a single-group design, with both an experimental clinical component and an observational field component. Both components used repeated measurement methods. The study population consisted of 45 adult patients with a mean age of 64.6 ± 8.5 years who were diagnosed with cardiac disease and who were taking anti-hypertensive medication. Blood pressure reactivity was operationalized with a speech protocol. During the speech protocol, BP was measured with an automatic device (Dinamap 825XT) while subjects talked about their health and about their usual day. Twenty-four hour ambulatory BP measurement (Spacelabs 90207 monitor) followed the speech protocol. ^ Results. Resting SBP and resting PP were significant predictors of 24-hour SBP, and resting SBP was a significant predictor of SBP load. No predictors were significant of 24-hour DBP or DBP load. ^ Conclusions. Initial resting BP and PP may be used in clinical settings to assess hypertension management. Future studies are necessary to confirm the ability of resting BP to predict ABP and BP load in older, medicated hypertensives. ^

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Objectives. To investigate procedural gender equity by assessing predisposing, enabling and need predictors of gender differences in annual medical expenditures and utilization among hypertensive individuals in the U.S. Also, to estimate and compare lifetime medical expenditures among hypertensive men and women in the U.S. ^ Data source. 2001-2004 the Medical Expenditure Panel Survey (MEPS);1986-2000 National Health Interview Survey (NHIS) and National Health Interview Survey linked to mortality in the National Death Index through 2002 (2002 NHIS-NDI). ^ Study design. We estimated total medical expenditure using four equations regression model, specific medical expenditures using two equations regression model and utilization using negative binomial regression model. Procedural equity was assessed by applying the Aday et al. theoretical framework. Expenditures were estimated in 2004 dollars. We estimated hypertension-attributable medical expenditure and utilization among men and women. ^ To estimate lifetime expenditures from ages 20 to 85+, we estimated medical expenditures with cross-sectional data and survival with prospective data. The four equations regression model were used to estimate average annual medical expenditures defined as sum of inpatient stay, emergency room visits, outpatient visits, office based visits, and prescription drugs expenditures. Life tables were used to estimate the distribution of life time medical expenditures for hypertensive men and women at different age and factors such as disease incidence, medical technology and health care cost were assumed to be fixed. Both total and hypertension attributable expenditures among men and women were estimated. ^ Data collection. We used the 2001-2004 MEPS household component and medical condition files; the NHIS person and condition files from 1986-1996 and 1997-2000 sample adult files were used; and the 1986-2000 NHIS that were linked to mortality in the 2002 NHIS-NDI. ^ Principal findings. Hypertensive men had significantly less utilization for most measures after controlling predisposing, enabling and need factors than hypertensive women. Similarly, hypertensive men had less prescription drug (-9.3%), office based (-7.2%) and total medical (-4.5%) expenditures than hypertensive women. However, men had more hypertension-attributable medical expenditures and utilization than women. ^ Expected total lifetime expenditure for average life table individuals at age 20, was $188,300 for hypertensive men and $254,910 for hypertensive women. But the lifetime expenditure that could be attributed to hypertension was $88,033 for men and $40,960 for women. ^ Conclusion. Hypertensive women had more utilization and expenditure for most measures than hypertensive men, possibly indicating procedural inequity. However, relatively higher hypertension-attributable health care of men shows more utilization of resources to treat hypertension related diseases among men than women. Similar results were reported in lifetime analyses.^ Key words: gender, medical expenditures, utilization, hypertension-attributable, lifetime expenditure ^

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The cytochromes P450 comprise a superfamily of heme-containing mono-oxygenases. These enzymes metabolize numerous xenobiotics, but also play a role in metabolism of endogenous compounds. The P450 1A1 enzyme generally metabolizes polycyclic aromatic hydrocarbons, and its expression can be induced by aryl hydrocarbon receptor (AhR) activation. CYP1A1 is an exception to the generality that the majority of CYPs demonstrate highest expression in liver; CYP1Al is present in numerous extrahepatic tissues, including brain. This P450 has been observed in two forms, wildtype (WT) and brain variant (BV), arising from alternatively spliced mRNA transcripts. The CYP1A1 BV mRNA presented an exon deletion and was detected in human brain but not liver tissue of the same individuals. ^ Quantitative PCR analyses were performed to determine CYP1A1 WT and BV transcript expression levels in normal, bipolar disorder or schizophrenic groups. In our samples, we show that CYP1A1 BV mRNA, when present, is found alongside the full-length form. Furthermore, we demonstrate a significant decrease in expression of CYP1A1 in patients with bipolar disorder or schizophrenia. The expression level was not influenced by post-mortem interval, tissue pH, age, tobacco use, or lifetime antipsychotic medication load. ^ There is no indication of increased brain CYP1A1 expression in normal smokers versus non-smokers in these samples. We observed slightly increased CYP1A1 expression only in bipolar and schizophrenic smokers versus non-smokers. This may be indicative of complex interactions between neuronal chemical environments and AhR-mediated CYP1A1 induction in brain. ^ Structural homology modeling demonstrated that P450 1A1 BV has several alterations to positions/orientations of substrate recognition site residues compared to the WT isoform. Automated substrate docking was employed to investigate the potential binding of neurological signaling molecules and neurotropic drugs, as well as to differentiate specificities of the two P450 1A1 isoforms. We consistently observed that the BV isoform produced energetically favorable substrate dockings in orientations not observed for the same substrate in the WT isoform. These results demonstrated that structural differences, namely an expanded substrate access channel and active site, confer greater capacity for unique compound docking positions suggesting a metabolic profile distinct from the wildtype form for these test compounds. ^