949 resultados para To-failure Method


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A simple extended finite field nuclear relaxation procedure for calculating vibrational contributions to degenerate four-wave mixing (also known as the intensity-dependent refractive index) is presented. As a by-product one also obtains the static vibrationally averaged linear polarizability, as well as the first and second hyperpolarizability. The methodology is validated by illustrative calculations on the water molecule. Further possible extensions are suggested

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An implicitly parallel method for integral-block driven restricted active space self-consistent field (RASSCF) algorithms is presented. The approach is based on a model space representation of the RAS active orbitals with an efficient expansion of the model subspaces. The applicability of the method is demonstrated with a RASSCF investigation of the first two excited states of indole

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Individuals sampled in hybrid zones are usually analysed according to their sampling locality, morphology, behaviour or karyotype. But the increasing availability of genetic information more and more favours its use for individual sorting purposes and numerous assignment methods based on the genetic composition of individuals have been developed. The shrews of the Sorex araneus group offer good opportunities to test the genetic assignment on individuals identified by their karyotype. Here we explored the potential and efficiency of a Bayesian assignment method combined or not with a reference dataset to study admixture and individual assignment in the difficult context of two hybrid zones between karyotypic species of the Sorex araneus group. As a whole, we assigned more than 80% of the individuals to their respective karyotypic categories (i.e. 'pure' species or hybrids). This assignment level is comparable to what was obtained for the same species away from hybrid zones. Additionally, we showed that the assignment result for several individuals was strongly affected by the inclusion or not of a reference dataset. This highlights the importance of such comparisons when analysing hybrid zones. Finally, differences between the admixture levels detected in both hybrid zones support the hypothesis of an impact of chromosomal rearrangements on gene flow.

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AIMS: BRAF is mutated in 50-60% of melanomas, but BRAF mutation in sarcomas has not been systematically evaluated. Some melanomas are spindled and may show no immunohistochemical evidence of melanocytic differentiation. Similarly, many sarcomas are undifferentiated, i.e. undifferentiated pleomorphic sarcomas (UPS). Diagnosing melanoma versus sarcoma in an undifferentiated spindle cell malignancy can be challenging. Our aim was to evaluate the prevalence of BRAF mutation in sarcomas and the use of BRAF mutational status in the diagnosis of spindle cell malignancies. METHODS AND RESULTS: BRAF mutational analysis was performed on tissue from 104 patients: 90 with sarcoma only (50 UPS) and 14 with sarcoma and melanoma (seven UPS). In the sarcoma-only group, BRAF mutation was absent. In the sarcoma-melanoma group, three sarcomas showed BRAF mutation; all were UPS, occurred after the melanomas and did not stain for melanocytic markers. One melanoma-sarcoma pair showed identical BRAF V600E mutations. CONCLUSIONS: The presence of BRAF mutation in these tumours raises the possibility that poorly differentiated spindle cell malignancies with BRAF mutation may represent melanomas, and BRAF mutational analysis should be considered in a patient with a spindle cell malignancy and a history of melanoma, as a positive result may indicate de-differentiated melanoma.

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The purpose of this paper is to describe the development and to test the reliability of a new method called INTERMED, for health service needs assessment. The INTERMED integrates the biopsychosocial aspects of disease and the relationship between patient and health care system in a comprehensive scheme and reflects an operationalized conceptual approach to case mix or case complexity. The method is developed to enhance interdisciplinary communication between (para-) medical specialists and to provide a method to describe case complexity for clinical, scientific, and educational purposes. First, a feasibility study (N = 21 patients) was conducted which included double scoring and discussion of the results. This led to a version of the instrument on which two interrater reliability studies were performed. In study 1, the INTERMED was double scored for 14 patients admitted to an internal ward by a psychiatrist and an internist on the basis of a joint interview conducted by both. In study 2, on the basis of medical charts, two clinicians separately double scored the INTERMED in 16 patients referred to the outpatient psychiatric consultation service. Averaged over both studies, in 94.2% of all ratings there was no important difference between the raters (more than 1 point difference). As a research interview, it takes about 20 minutes; as part of the whole process of history taking it takes about 15 minutes. In both studies, improvements were suggested by the results. Analyses of study 1 revealed that on most items there was considerable agreement; some items were improved. Also, the reference point for the prognoses was changed so that it reflected both short- and long-term prognoses. Analyses of study 2 showed that in this setting, less agreement between the raters was obtained due to the fact that the raters were less experienced and the scoring procedure was more susceptible to differences. Some improvements--mainly of the anchor points--were specified which may further enhance interrater reliability. The INTERMED proves to be a reliable method for classifying patients' care needs, especially when used by experienced raters scoring by patient interview. It can be a useful tool in assessing patients' care needs, as well as the level of needed adjustment between general and mental health service delivery. The INTERMED is easily applicable in the clinical setting at low time-costs.

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The application of the Fry method to measure strain in deformed porphyritic granites is discussed. This method requires that the distribution of markers has to satisfy at least two conditions. It has to be homogeneous and isotropic. Statistics on point distribution with the help of a Morishita diagram can easily test homogeneity. Isotropy can be checked with a cumulative histogram of angles between points. Application of these tests to undeformed (Mte Capanne granite, Elba) and to deformed (Randa orthogneiss, Alps of Switzerland) porphyritic granite reveals that their K-feldspars phenocrysts both satisfy these conditions and can be used as strain markers with the Fry method. Other problems are also examined. One is the possible distribution of deformation on discrete shear-bands. Providing several tests are met, we conclude that the Fry method can be used to estimate strain in deformed porphyritic granites. (c) 2006 Elsevier Ltd. All rights reserved.

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The research presented in this report provides the basis for the development of a new procedure to be used by the Iowa DOT and cities and counties in the state to deal with detours. Even though the project initially focused on investigating new tools to determine condition and compensation, the focus was shifted to traffic and the gas tax method to set the basis for the new procedure. It was concluded that the condition-based approach, even though accurate and consistent condition evaluations can be achieved, is not feasible or cost effective because of the current practices of data collection (two-year cycle) and also the logistics of the procedure (before and after determination). The gas tax method provides for a simple, easy to implement, and consistent approach to dealing with compensation for use of detours. It removes the subjectivity out of the current procedures and provides for a more realistic (traffic based) approach to the compensation determination.

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AIM: To prospectively study the intraocular pressure (IOP) lowering effect and safety of the new method of very deep sclerectomy with collagen implant (VDSCI) compared with standard deep sclerectomy with collagen implant (DSCI). METHODS: The trial involved 50 eyes of 48 patients with medically uncontrolled primary and secondary open-angle glaucoma, randomized to undergo either VDSCI procedure (25 eyes) or DSCI procedure (25 eyes). Follow-up examinations were performed before surgery and after surgery at day 1, at week 1, at months 1, 2, 3, 6, 9, 12, 18, and 24 months. Ultrasound biomicroscopy was performed at 3 and 12 months. RESULTS: Mean follow-up period was 18.6+/-5.9 (VDSCI) and 18.9+/-3.6 (DSCI) months (P=NS). Mean preoperative IOP was 22.4+/-7.4 mm Hg for VDSCI and 20.4+/-4.4 mm Hg for DSCI eyes (P=NS). Mean postoperative IOP was 3.9+/-2.3 (VDSCI) and 6.3+/-4.3 (DSCI) (P<0.05) at day 1, and 12.2+/-3.9 (VDSCI) and 13.3+/-3.4 (DSCI) (P=NS) at month 24. At the last visit, the complete success rate (defined as an IOP of < or =18 mm Hg and a percentage drop of at least 20%, achieved without medication) was 57% in VDSCI and 62% in DSCI eyes (P=NS) ultrasound biomicroscopy at 12 months showed a mean volume of the subconjunctival filtering bleb of 3.9+/-4.2 mm3 (VDSCI) and 6.8+/-7.5 mm3 (DSCI) (P=0.426) and 5.2+/-3.6 mm3 (VDSCI) and 5.4+/-2.9 mm3 (DSCI) (P=0.902) for the intrascleral space. CONCLUSIONS: Very deep sclerectomy seems to provide stable and good control of IOP at 2 years of follow-up with few postoperative complications similar to standard deep sclerectomy with the collagen implant.

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The pathophysiological role of an increase in circulating vasopressin in sustaining global and regional vasoconstriction in patients with congestive heart failure has not been established, particularly in patients with hyponatraemia. To assess this further, 20 patients with congestive heart failure refractory to digoxin and diuretics were studied before and 60 minutes after the intravenous injection (5 micrograms/kg) of the vascular antagonist of vasopressin [1(beta-mercapto-beta,beta-cyclopentamethylene-propionic acid), 2-(0-methyl) tyrosine] arginine vasopressin. Ten patients were hyponatraemic (plasma sodium less than 135 mmol/l) and 10 were normonatraemic. In both groups of patients the vascular vasopressin antagonist did not alter systemic or pulmonary artery pressures, right atrial pressure, pulmonary capillary wedge pressure, cardiac index, or vascular resistances. Furthermore, there was no change in skin and hepatic blood flow in either group after the injection of the vascular antagonist. Only one patient in the hyponatraemic group showed considerable haemodynamic improvement. He had severe congestive heart failure and a high concentration of plasma vasopressin (51 pmol/l). Plasma renin activity, vasopressin, or catecholamine concentrations were not significantly changed in response to the administration of the vasopressin antagonist in either the hyponatraemic or the normonatraemic groups. Patients with hyponatraemia, however, had higher baseline plasma catecholamine concentrations, heart rate, pulmonary pressure and resistance, and lower hepatic blood flow than patients without hyponatraemia. Plasma vasopressin and plasma renin activity were slightly, though not significantly, higher in the hyponatraemic group. Thus the role of vasopressin in sustaining regional or global vasoconstriction seems limited in patients with congestive heart failure whether or not concomitant hyponatraemia is present. Vasopressin significantly increases the vascular tone only in rare patients with severe congestive heart failure and considerably increased vasopressin concentrations. Patients with hyponatraemia do, however, have raised baseline catecholamine concentrations, heart rate, pulmonary arterial pressure and resistance, and decreased hepatic blood flow.

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This study aimed at assessing beliefs about the benefits and barriers to adherence to daily self-monitoring of weight/edema in patients with heart failure, and the influence of demographic and clinical variables on those beliefs. 105 patients were interviewed. The mean of the subscales Benefits and Barriers were 20.2 (± 5.7) and 30.1 (±7.1), respectively. Patients perceived that adherence to daily self-monitoring of weight/edema could keep them healthy, improve their quality of life and decrease the chances of readmission. Approximately half of patients (46.7%) reported forgetting this measure. Those who controlled weight once a month were more likely to have barriers to adherence (OR= 6.6; IC 95% 1.9-13.8; p=0.01), showing this measure to be the main factor related to perceived barriers. Education in health can contribute with the development of strategies aimed at lowering barriers and increasing benefits of this control.

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Objective This study assessed pharmacological treatment adherence using the Morisky-Green Test and identified related variables. Method A longitudinal and retrospective study examined 283 patients with hypertension (62.5% women, 73.4 [10.9] years old) who were being monitored by a chronic disease management program for 17 months between 2011 and 2012. Nurses performed all the actions of the program, which consisted of advice via telephone and periodic home visits based on the risk stratification of the patients. Results A significant increase in treatment adherence (25.1% vs. 85.5%) and a decrease in blood pressure were observed (p<0.05). Patients with hypertension and chronic renal failure as well as those treated using angiotensin-converting enzyme inhibitors were the most adherent (p<0.05). Patients with hypertension who received angiotensin receptor blockers were less adherent (p<0.05). Conclusions Strategies such as nurse-performed chronic disease management can increase adherence to anti-hypertensive treatment and therefore contribute to the control of blood pressure, minimizing the morbidity profiles of patients with hypertension.

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Introduction: Because it decreases intubation rate and mortality, NIV has become first-line treatment in case of hypercapnic respiratory failure (HRF). Whether this approach is equally successful for all categories of HRF patients is however debated. We assessed if any clinical characteristics of HRF patients were associated with NIV intensity, success, and outcome, in order to identify prognostic factors. Methods: Retrospective analysis of the clinical database (clinical information system and MDSi) of patients consecutively admitted to our medico-surgical ICU, presenting with HRF (defined as PaCO2 >50 mm Hg), and receiving NIV between January 2009 and December 2010. Demographic data, medical diagnoses (including documented chronic lung disease), reason for ICU hospitalization, recent surgical interventions, SAPS II and McCabe scores were extracted from the database. Total duration of NIV and the need for tracheal intubation during the 5 days following the first hypercapnia documentation, as well as ICU and hospital mortality were recorded. Results are reported as median [IQR]. Comparisons with Chi2 or Kruskal-Wallis tests, p <0.05 (*). Results: 164 patients were included, 45 (27.4%) of whom were intubated after 10 [2-34] hours, after having received 7 [2-19] hours of NIV. NIV successful patients received 15 [5-22] hours of NIV for up to 5 days. Intubation was correlated with increased ICU (20% vs. 3%, p <0.001) and hospital (46.7% vs. 30.2, p >0.05) mortality. Conclusions: A majority of patients requiring NIV for hypercapnic respiratory failure in our ICU have no diagnosed chronic pulmonary disease. These patients tend to have increased ICUand hospital mortality. The majority of patients were non-surgical, a feature correlated with increased hospital mortality. Beside usual predictors of severity such as age and SAPS II, absence of diagnosed chronic pulmonary disease and non-operative state appear to be associated with increased mortality. Further studies should explore whether these patients are indeed more prone to an adverse outcome and which therapeutic strategies might contribute to alter this course.

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PURPOSE: To evaluate the utility of inversion recovery with on-resonant water suppression (IRON) in combination with injection of the long-circulating monocrystalline iron oxide nanoparticle (MION)-47 for contrast material-enhanced magnetic resonance (MR) angiography. MATERIALS AND METhods: Experiments were approved by the institutional animal care committee. Eleven rabbits were imaged at baseline before injection of a contrast agent and then serially 5-30 minutes, 2 hours, 1 day, and 3 days after a single intravenous bolus injection of 80 micromol of MION-47 per kilogram of body weight (n = 6) or 250 micromol/kg MION-47 (n = 5). Conventional T1-weighted MR angiography and IRON MR angiography were performed on a clinical 3.0-T imager. Signal-to-noise and contrast-to-noise ratios were measured in the aorta of rabbits in vivo. Venous blood was obtained from the rabbits before and after MION-47 injection for use in phantom studies. RESULTS: In vitro blood that contained MION-47 appeared signal attenuated on T1-weighted angiograms, while characteristic signal-enhanced dipolar fields were observed on IRON angiograms. In vivo, the vessel lumen was signal attenuated on T1-weighted MR angiograms after MION-47 injection, while IRON supported high intravascular contrast by simultaneously providing positive signal within the vessels and suppressing background tissue (mean contrast-to-noise ratio, 61.9 +/- 12.4 [standard deviation] after injection vs 1.1 +/- 0.4 at baseline, P < .001). Contrast-to-noise ratio was higher on IRON MR angiograms than on conventional T1-weighted MR angiograms (9.0 +/- 2.5, P < .001 vs IRON MR angiography) and persisted up to 24 hours after MION-47 injection (76.2 +/- 15.9, P < .001 vs baseline). CONCLUSION: IRON MR angiography in conjunction with superparamagnetic nanoparticle administration provides high intravascular contrast over a long time and without the need for image subtraction.