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21.
P. López Varo J.A. Jiménez Tejada J.A. López Villanueva M.J. Deen 《Organic Electronics》2014,15(10):2536-2545
A method to characterize metal–organic contacts subjected to controlled technological treatments or unintentional degradation processes is proposed. The procedure is useful to characterize different fundamental aspects of a metal–organic structure such as the height of the interface energy barrier, the presence of impurities or trapping effects and the carrier mobility. Current–voltage curves in organic diodes are analyzed and the value of the free carrier density at the metal–organic interface is extracted and discussed. The charge carrier density is chosen for this analysis as this is one of the key physical parameters in the understanding of the physical processes involved in the device operation. The extracted charge, when described as a function of the current density, gives information about the doping and impurity concentration, the effective barrier seen by the carriers at the metal–organic interface or effective barriers seen by the carriers in the hopping processes across the organic material. An important advantage of the proposed procedure is the low computational time. Also, the procedure aims to provide a quick analysis for researchers on how the physical properties of the devices are evolving when they are technologically altered or degraded. 相似文献
22.
M Sàbat L Kolle G Soriano J Ortiz J Pamplona MT Novella C Villanueva S Sainz J Torras J Balanzó C Guarner 《Canadian Metallurgical Quarterly》1998,93(12):2457-2462
OBJECTIVE: Selective intestinal decontamination with norfloxacin is useful in the prevention of bacterial infections in cirrhotic patients with gastrointestinal bleeding. However, bleeding cirrhotic patients with ascites, encephalopathy, or shock are at high risk to develop bacterial infections in spite of prophylactic norfloxacin. The aim of this study was to assess whether the addition of intravenous ceftriaxone could improve the efficacy of prophylaxis with norfloxacin in these patients. METHODS: Fifty-six cirrhotic patients with gastrointestinal hemorrhage and ascites, encephalopathy, or shock were randomized into two groups: Group 1 (n = 28) received oral norfloxacin 400 mg/12 h for 7 days, and group 2 (n = 28) received norfloxacin plus intravenous ceftriaxone 2 g daily during the first 3 days of admission. RESULTS: Ten patients were excluded because of community-acquired infection, surgery, or death within the first 24 h. The incidence of bacterial infections during hospitalization was 18.1% in group 1 and 12.5% in group 2 (p = NS). The incidence of severe infections (spontaneous bacterial peritonitis, bacteremia, or pneumonia) was also similar in both groups: 9% in group 1 versus 8.3% in group 2 (p = NS). There were no statistical differences between the two groups with respect to duration of hospitalization or mortality. The cost of antibiotic therapy (including prophylaxis and treatment of infections) was significantly higher in group 2. CONCLUSION: These results suggest that the addition of intravenous ceftriaxone during the first 3 days of hospitalization does not improve the cost-efficacy of oral norfloxacin in the prevention of bacterial infections in cirrhotic patients with gastrointestinal bleeding and high risk of infection. 相似文献
23.
María-José Villanueva María-Dolores Rodríguez Araceli Redondo María-Dolores Saco 《European Food Research and Technology》1996,203(4):345-350
Modifications of dietary fibre in beetroot during autoclaving have been evaluated by different methods: acid detergent (raw=1.45%; processed=1.17%) and neutral detergent (raw=2.30%; processed=2.00%), the enzymatic-gravimetric method of Asp (raw=3.35%; processed=3.34%), HPLC (raw=1.42%; processed=1.60%) and 3,5-dimethylphenol (raw=0.36; processed=0.28%). The correlation between different methodologies was studied. Autoclaving was carried out at 121°C under pressure for 15 min. Variance analysis indicated that quantitative variations originating in the thermic treatment were not statistically significant (P>0.05). 相似文献
24.
25.
SS Samaan HR Schumacher T Villanueva R Levin BF Atkinson 《Canadian Metallurgical Quarterly》1994,38(4):582-588
We present the first report in which cells in synovial fluid from a patient with multicentric reticulohistiocytosis (MRH) were studied by immunocytochemistry for correlation with routine light and electron microscopy. MRH cells stained predominantly for lymphocyte-related surface antigens and not for the monocyte marker LEU M3 (CD14). These findings suggest a lymphocytic origin of MRH cells and not a histiocytic origin, as previously suggested. In addition, large numbers of membrane-bound, electron-dense, secretory-type granules were found ultrastructurally in the cytoplasm of these cells. 相似文献
26.
The inclusion of field bean (Vicia faba) in diets for growing experimental animals, reduced their growth performance in a similar way as compared with controls fed a casein diet, with 0.2% tannic acid. Hydroalcoholic extracts or isolated tannins obtained from Vicia faba seeds, decreased the intestinal transport of D-glucose. The addition of 0.05, 0.1 or 0.2% of tannic acid to the perfusion solutions containing D-glucose proportionally diminished the intestinal uptake of sugar according to its poliphenolic content. It has been postulated that polyphenols reduce, at least partially, the nutritive value of legumes, by altering monosaccharide absorption. Other constituents, however, could also be involved. 相似文献
27.
A. Villanueva J.M. Serrano 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》1986,1(3-4):237-241
Of all the possible alternatives for a link across the Straits of Gibraltar (bridge, tunnel, etc.), there is no doubt that building a subsurface tunnel under the seabed is one of the options being considered most seriously. Within this context, the geological and geotechnical work begun several years ago by Spain and Morocco is fulfilling the scheduled stages. This paper describes the basic criteria used in drawing up these schedules of studies and gives a report on the state of the research being carried out. 相似文献
28.
Frisch Michael B.; Cornell John; Villanueva Michael; Retzlaff Paul J. 《Canadian Metallurgical Quarterly》1992,4(1):92
Details the psychometric evaluation of the Quality of Life Inventory (QOLI), a measure of life satisfaction that may complement symptom-oriented measures of psychological functioning in evaluating the outcome of interventions aimed at ameliorating mental disorders, disabling physical illnesses, and community-wide social problems. Test–retest coefficients for the QOLI ranged from .80 to .91, and internal consistency coefficients ranged from .77 to .89 across 3 clinical and 3 nonclinical samples. QOLI item–total correlations were found to be adequate, and the QOLI had significantly positive correlations with 7 related measures of subjective well-being, including a peer rating and clinical interview measure. Significant negative correlations were obtained between the QOLI and measures of general psychopathology and depression. Clinical and nonclinical criterion groups differed significantly in mean QOLI scores. QOLI norms are presented, and the usefulness of the QOLI for assessing treatment outcome and for psychotherapy treatment planning is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
29.
C Villanueva J Balanzó MT Novella G Soriano S Sáinz X Torras X Cussó C Guarner F Vilardell 《Canadian Metallurgical Quarterly》1996,334(25):1624-1629
BACKGROUND: Patients who have bleeding from esophageal varices are at high risk for rebleeding and death. We compared the efficacy and safety of endoscopic sclerotherapy with the efficacy and safety of nadolol plus isosorbide mononitrate for the prevention of variceal rebleeding. METHODS: Eighty-six hospitalized patients with cirrhosis and bleeding from esophageal varices diagnosed by endoscopy were randomly assigned to treatment with repeated sclerotherapy (43 patients) or nadolol plus isosorbide-5-mononitrate (43 patients). The primary outcomes were rebleeding, death, and complications. The hepatic venous pressure gradient was measured at base line and after three months. RESULTS: Base-line data were similar in the two groups, and the median follow-up was 18 months in both. Eleven patients in the medication group and 23 in the sclerotherapy group had rebleeding. The actuarial probability of remaining free of rebleeding was higher in the medication group for all episodes related to portal hypertension (P = 0.001) and variceal rebleeding (P = 0.002). Four patients in the medication group and nine in the sclerotherapy group died (P = 0.07 for the difference in the actuarial probability of survival). Seven patients in the medication group and 16 in the sclerotherapy group had treatment-related complications (P = 0.03). Thirty-one patients in the medication group underwent two hemodynamic studies; 1 of the 13 patients with more than a 20 percent decrease in the hepatic venous pressure gradient had rebleeding, as compared with 8 of the 18 with smaller decreases in the pressure gradient (P = 0.04) for the actuarial probability of rebleeding at two years). CONCLUSIONS: As compared with sclerotherapy, nadolol plus isosorbide mononitrate significantly decreased the risk of rebleeding from esophageal varices. 相似文献
30.