914 resultados para purely sequential procedure
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A 54-year-old patient who had an isolated small polar thalamic infarct and acute global amnesia with slight frontal type dysfunction but without other neurological dysfunction was studied. Memory improved partially within 8 months. At all stages the impairment was more severe for verbal than non-verbal memory. Autobiographic recollections and newly acquired information tended to be disorganised with respect to temporal order. Procedural memory was unaffected. Both emotional involvement and pleasure in reading were lost. On MRI, the infarct was limited to the left anterior thalamic nuclei and the adjacent mamillothalamic tract. The regional cerebral metabolic rate of glucose (measured with PET) was decreased on the left in the thalamus, amygdala, and posterior cingulate cortex 2 weeks after the infarct, and in the thalamus and posterior cingulate cortex 9 months later. These findings stress the specific role of the left anterior thalamic region in memory and confirm that longlasting amnesia from a thalamic lesion can occur without significant structural damage to the dorsomedial nucleus. Furthermore, they suggest that the anterior thalamic nuclei and possibly their connections with the posterior cingulate cortex play a role in emotional involvement linked to ipsilateral hemispheric functions.
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Purpose: Letrozole (LET) has recently been shown to be superior to tamoxifen for postmenopausal patients (pts). In addition, LET radiosensitizes breast cancer cells in vitro. We conducted a phase II randomized study to evaluate concurrent and sequential radiotherapy (RT)-LET in the adjuvant setting. We present here clinical results with a minimum follow-up of 24 months. Patients and Methods: Postmenopausal pts with early-stage breast cancer were randomized after conservative surgery to either: A) concurrent RT-LET (LET started 3 weeks before the first day of RT) or B) sequential RT-LET (LET started 3 weeks after the end of RT). Whole breast RT was delivered to a total dose of 50 Gy. A 10-16 Gy boost was allowed according to age and pathological prognostic factors. Pts were stratified by center, adjuvant chemotherapy, boost, and radiation-induced CD8 apoptosis (RILA). RILA was performed before RT as previously published (Ozsahin et al. Clin Cancer Res, 2005). An independent monitoring committee reviewed individual safety data. Skin toxicities were evaluated by two different clinicians at each medical visit (CTCAE v3.0). Lung CT-scan and functional pulmonary tests were performed regularly. DNA samples were screened for SNPs in candidate genes as recently published (Azria et al., Clin Cancer Res, 2008). Results: A total of 150 pts were randomized between 01/05 and 02/07. Median follow-up is 26 months (range, 3-40 months). No statistical differences were identified between the two arms in terms of mean age; initial TNM; median surgical bed volume; post surgical breast volume. Chemotherapy and RT boost were delivered in 19% and 38% of pts, respectively. Nodes received 50 Gy in 23% of patients without differences between both arms. During RT and within the first 6 weeks after RT, 10 patients (6.7%) presented grade 3 acute skin dermatitis during RT but no differences were observed between both arms (4 and 6 patients in arm A and B, respectively). At 26 month of follow-up, grade 2 and more radiation-induced subcutaneous fibrosis (RISCF) was present in 4 patients (3%) without any difference between arm A (n = 2) and B (n = 2), p=0.93. In both arms, all patients that presented a RICSF had a RILA lower than 16%. Sensitivity and specificity were 100% and 39%, respectively.No acute lung toxicities were observed and quality of life was good to excellent for all patients.SNPs analyses are still on-going (Pr Rosenstein, NY). Conclusion: Acute and early late grade 2 dermatitis were similar in both arms. The only factor that influenced RISCF was a low radiation-induced lymphocyte apoptosis yield. We confirmed prospectively the capacity of RILA for identifying hypersensitive patients to radiation. Indeed, patients with RILA superior to 16% did not present late effects to radiation and confirmed the first prospective trial we published in 2005 (Ozsahin et al., Clin Cancer Res).
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We study the problem of the partition of a system of initial size V into a sequence of fragments s1,s2,s3 . . . . By assuming a scaling hypothesis for the probability p(s;V) of obtaining a fragment of a given size, we deduce that the final distribution of fragment sizes exhibits power-law behavior. This minimal model is useful to understanding the distribution of avalanche sizes in first-order phase transitions at low temperatures.
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A method for characterizing the microroughness of samples in optical coating technology is developed. Measurements over different spatial-frequency ranges are composed into a single power spectral density (PSD) covering a large bandwidth. This is followed by the extraction of characteristic parameters through fitting of the PSD to a suitable combination of theoretical models. The method allows us to combine microroughness measurements performed with different techniques, and the fitting procedure can be adapted to any behavior of a combined PSD. The method has been applied to a set of ion-beam-sputtered fluoride vacuum-UV coatings with increasing number of alternative low- and high-index layers. Conclusions about roughness development and microstructural growth are drawn.
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The multiscale finite-volume (MSFV) method is designed to reduce the computational cost of elliptic and parabolic problems with highly heterogeneous anisotropic coefficients. The reduction is achieved by splitting the original global problem into a set of local problems (with approximate local boundary conditions) coupled by a coarse global problem. It has been shown recently that the numerical errors in MSFV results can be reduced systematically with an iterative procedure that provides a conservative velocity field after any iteration step. The iterative MSFV (i-MSFV) method can be obtained with an improved (smoothed) multiscale solution to enhance the localization conditions, with a Krylov subspace method [e.g., the generalized-minimal-residual (GMRES) algorithm] preconditioned by the MSFV system, or with a combination of both. In a multiphase-flow system, a balance between accuracy and computational efficiency should be achieved by finding a minimum number of i-MSFV iterations (on pressure), which is necessary to achieve the desired accuracy in the saturation solution. In this work, we extend the i-MSFV method to sequential implicit simulation of time-dependent problems. To control the error of the coupled saturation/pressure system, we analyze the transport error caused by an approximate velocity field. We then propose an error-control strategy on the basis of the residual of the pressure equation. At the beginning of simulation, the pressure solution is iterated until a specified accuracy is achieved. To minimize the number of iterations in a multiphase-flow problem, the solution at the previous timestep is used to improve the localization assumption at the current timestep. Additional iterations are used only when the residual becomes larger than a specified threshold value. Numerical results show that only a few iterations on average are necessary to improve the MSFV results significantly, even for very challenging problems. Therefore, the proposed adaptive strategy yields efficient and accurate simulation of multiphase flow in heterogeneous porous media.
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A computer-aided method to improve the thickness uniformity attainable when coating multiple substrates inside a thermal evaporation physical vapor deposition unit is presented. The study is developed for the classical spherical (dome-shaped) calotte and also for a plane sector reversible holder setup. This second arrangement is very useful for coating both sides of the substrate, such as antireflection multilayers on lenses. The design of static correcting shutters for both kinds of configurations is also discussed. Some results of using the method are presented as an illustration.
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Phosphate release kinetics from manures are of global interest because sustainable plant nutrition with phosphate will be a major concern in the future. Although information on the bioavailability and chemical composition of P present in manure used as fertilizer are important to understand its dynamics in the soil, such studies are still scarce. Therefore, P extraction was evaluated in this study by sequential chemical fractionation, desorption with anion-cation exchange resin and 31P nuclear magnetic resonance (31P-NMR) spectroscopy to assess the P forms in three different dry manure types (i.e. poultry, cattle and swine manure). All three methods showed that the P forms in poultry, cattle and swine dry manures are mostly inorganic and highly bioavailable. The estimated P pools showed that organic and recalcitrant P forms were negligible and highly dependent on the Ca:P ratio in manures. The results obtained here showed that the extraction of P with these three different methods allows a better understanding and complete characterization of the P pools present in the manures.
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OBJECTIVES: Thirty-two consecutive isolated modified Blalock Taussig (BT) shunts performed in infancy since 2004 were reviewed and analysed to identify the risk factors for shunt intervention and mortality. METHODS: Sternotomy was the only approach used. Median age and weight were 10.5 (range 1-74) days and 2.9 (1.9-4.4) kg, respectively. Shunt palliation was performed for biventricular hearts (Tetralogy of Fallot/double outlet right ventricle/transposition of great arteries_ventricular septal defect_pulmonary stenosis/pulmonary atresia_ventricular septal defect/others) in 21, and univentricular hearts in 11, patients. Hypoplastic left heart syndrome patients were excluded. Two procedures required cardiopulmonary bypass. Median shunt size was 3.5 (3-4) mm and median shunt size/kg body weight was 1.2 (0.9-1.7) mm/kg. Reduction in shunt size was necessary in 5 of 32 (16%) patients. RESULTS: Three of 32 (9%) patients died after 3 (1-15) days due to cardiorespiratory decompensation. Lower body weight (P = 0.04) and bigger shunt size/kg of body weight (P = 0.004) were significant risk factors for mortality. Acute shunt thrombosis was observed in 3 of 32 (9%), none leading to death. Need for cardiac decongestive therapy was associated with univentricular hearts (P < 0.001), bigger shunt size (P = 0.054) and longer hospital stay (P = 0.005). Twenty-eight patients have undergone a successful shunt takedown at a median age of 5.5 (0.5-11.9) months, without late mortality. CONCLUSIONS: Palliation with a modified BT shunt continues to be indicated despite increased thrust on primary corrective surgery. Though seemingly simple, it is associated with significant morbidity and mortality. Effective over-shunting and acute shunt thrombosis are the lingering problems of shunt therapy.
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In general, Latosols have low levels of available P, however, the influence of the parent material seems to be decisive in defining the pool and predominant form of P in these soils. This study evaluated P availability by extraction with Mehlich-1 (M-1) and Ion Exchange Resin (IER), from samples of B horizons of Ferric and Perferric Latosols developed from different parent materials. To this end, in addition to the physical and chemical characterization of soils, 10 sequential extractions were performed with M-1 and IER from samples of B horizons (depth between 0.8 and 1.0 m). Total contents of Ca, P, Fe, Al, and Ti were determined after digestion with nitric, hydrofluoric and perchloric acids. The effects of sequential P extractions on Fe oxides were also evaluated from the analyses of dithionite-citrate-bicarbonate and ammonium acid oxalate. The high similarity between contents of P accumulated after sequential extractions with M-1 and IER in soils developed on tuffite indicated a predominance of P-Ca. Higher contents of P after a single IER extraction show greater efficiency in P removal from highly weathered soils, as from the Latosols studied here. The P contents also show the high sensitivity of extractant M-1 in highly buffered soils. Furthermore, a single extraction with extractant M-1 or IER is not sufficient to estimate the amount of labile P in these soils.
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Report of agreed upon procedure of the Medicaid demonstration project, entitled IowaCare, for the year ended June 30, 2011
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The present research project was designed to identify the typical Iowa material input values that are required by the Mechanistic-Empirical Pavement Design Guide (MEPDG) for the Level 3 concrete pavement design. It was also designed to investigate the existing equations that might be used to predict Iowa pavement concrete for the Level 2 pavement design. In this project, over 20,000 data were collected from the Iowa Department of Transportation (DOT) and other sources. These data, most of which were concrete compressive strength, slump, air content, and unit weight data, were synthesized and their statistical parameters (such as the mean values and standard variations) were analyzed. Based on the analyses, the typical input values of Iowa pavement concrete, such as 28-day compressive strength (f’c), splitting tensile strength (fsp), elastic modulus (Ec), and modulus of rupture (MOR), were evaluated. The study indicates that the 28-day MOR of Iowa concrete is 646 + 51 psi, very close to the MEPDG default value (650 psi). The 28-day Ec of Iowa concrete (based only on two available data of the Iowa Curling and Warping project) is 4.82 + 0.28x106 psi, which is quite different from the MEPDG default value (3.93 x106 psi); therefore, the researchers recommend re-evaluating after more Iowa test data become available. The drying shrinkage (εc) of a typical Iowa concrete (C-3WR-C20 mix) was tested at Concrete Technology Laboratory (CTL). The test results show that the ultimate shrinkage of the concrete is about 454 microstrain and the time for the concrete to reach 50% of ultimate shrinkage is at 32 days; both of these values are very close to the MEPDG default values. The comparison of the Iowa test data and the MEPDG default values, as well as the recommendations on the input values to be used in MEPDG for Iowa PCC pavement design, are summarized in Table 20 of this report. The available equations for predicting the above-mentioned concrete properties were also assembled. The validity of these equations for Iowa concrete materials was examined. Multiple-parameters nonlinear regression analyses, along with the artificial neural network (ANN) method, were employed to investigate the relationships among Iowa concrete material properties and to modify the existing equations so as to be suitable for Iowa concrete materials. However, due to lack of necessary data sets, the relationships between Iowa concrete properties were established based on the limited data from CP Tech Center’s projects and ISU classes only. The researchers suggest that the resulting relationships be used by Iowa pavement design engineers as references only. The present study furthermore indicates that appropriately documenting concrete properties, including flexural strength, elastic modulus, and information on concrete mix design, is essential for updating the typical Iowa material input values and providing rational prediction equations for concrete pavement design in the future.
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A radiochemical procedure was developed for the sequential determination of Pu and Am radioisotopes in environmental samples. The radioisotope activities were then used to assess the origin and release date of the environmental plutonium. The radioanalytical procedure is based on the separation of Pu and Am on selective extraction chromatographic resins (Eichrom TEVA and DGA). Alpha sources were prepared by electrodeposition on stainless steel discs, and the alpha emitting radionuclides (238Pu, 239,240Pu and 241Am) were measured by alpha spectrometry. For the determination of the beta emitting 241Pu, the Pu alpha source was leached in hot concentrated nitric acid and the Pu fraction further purified by extraction chromatography on a small column of TEVA resin (100 μg of resin in a pipette tip). 241Pu is then measured by ultra low level liquid scintillation counting. Due to the lack of reference material for 241Pu, the proposed radiochemical method was nevertheless validated using four IAEA reference sediments with information values of 241Pu. The proposed method was then used to determine the 238Pu, 239,240Pu, 241Pu and 241Am activity concentrations in alpine soils of France and Switzerland. The soil is the primary receptor of the atmospheric radioactive fallout and, because of the strong binding interaction with soils particles, the isotopes are little fractionated. Therefore, the activity ratios 241Pu/239+240Pu and 238Pu/239,240Pu in soil samples were used to determine the origin (source) and date of the Pu contamination in the investigated alpine sites. The 241Pu/239,240Pu and 238Pu/239,240Pu activity ratios confirmed that the main origin of Pu in the alpine soils was the global fallout from the nuclear bomb tests (NBT) in the fifties and sixties. Furthermore, the 241Pu/241Am activity ratios were used to determine the age of the Pu contamination, which is also an important data for distinguishing the Pu sources. The estimation of the date of the contamination, by the 241Pu/241Am age-dating method, further confirmed the NBT as the Pu source. However, the 241Pu/241Am dating method was limited to samples where Pu-Am fractionation was insignificant. If any, the contribution of the Chernobyl accident in the studied sites is negligible.