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101.
Iñaki ZalakainJose Angel Ramos Raquel FernandezHaritz Etxeberria Iñaki Mondragon 《Thin solid films》2011,519(6):1882-1885
Highly oriented pyrolitic graphite (HOPG) is a useful substrate to visualize epitaxial formation due to its crystallographic structure. The morphology of a poly(styrene-b-isoprene-b-styrene) block copolymer thin film on a HOPG substrate was investigated by atomic force microscopy. Block copolymer domains generated a morphology with triangular regularity. This arrangement was induced by the HOPG substrate structure due to van der Waals attraction between the HOPG π-conjugated system and aromatic ring of polystyrene domains. However, increasing the film thickness, the substrate effect on the surface morphology decreased. As a consequence, film surfaces showed the coexistence of different structures such as highly aligned cylinders and perforated lamellae. When film thickness exceeded a threshold value, the substrate did not have effect in the surface arrangements and the surface showed a similar morphology to that existing in bulk. 相似文献
102.
Degradation of the antibiotic amoxicillin by photo-Fenton process--chemical and toxicological assessment 总被引:1,自引:0,他引:1
The influence of iron species on amoxicillin (AMX) degradation, intermediate products generated and toxicity during the photo-Fenton process using a solar simulator were evaluated in this work. The AMX degradation was favored in the presence of the potassium ferrioxalate complex (FeOx) when compared to FeSO4. Total oxidation of AMX in the presence of FeOx was obtained after 5 min, while 15 min were necessary using FeSO4. The results obtained with Daphnia magna biossays showed that the toxicity decreased from 65 to 5% after 90 min of irradiation in the presence of FeSO4. However, it increased again to a maximum of 100% after 150 min, what indicates the generation of more toxic intermediates than AMX, reaching 45% after 240 min. However, using FeOx, the inhibition of mobility varied between 100 and 70% during treatment, probably due to the presence of oxalate, which is toxic to the neonates. After 240 min, between 73 and 81% TOC removal was observed. Different pathways of AMX degradation were suggested including the opening of the four-membered β-lactamic ring and further oxidations of the methyl group to aldehyde and/or hydroxylation of the benzoic ring, generating other intermediates after bound cleavage between different atoms and further oxidation to carboxylates such acetate, oxalate and propionate, besides the generation of nitrate and ammonium. 相似文献
103.
104.
F Herranz Amo F Camú?ez JM Díez Cordero F Verdú Tartajo E Lledo García G Bueno Chamon 《Canadian Metallurgical Quarterly》1998,51(8):818-820
OBJECTIVE: To describe a case of uretero-iliac fistula, an extremely rare condition that is not easily diagnosed. METHODS/RESULTS: Herein we describe a 76-year-old female who had undergone repeated pelvic surgery for adenocarcinoma of the sigmoid. She had a right ureteral fistula that had been managed conservatively by insertion of a ureteral catheter. Diagnosis was made by selective arteriography of the iliac arteries. The patient was submitted to surgery; primary closure of the arterial fistula and nephroureterectomy were performed. CONCLUSIONS: Uretero-iliac fistula should be suspected in patients with a history of repeated pelvic surgery and ureteral catheter placement that present with massive hematuria. 相似文献
105.
Raquel Urtasun Pascal Glardon Ronan Boulic Daniel Thalmann Pascal Fua 《Computer Graphics Forum》2004,23(4):799-812
Representing motions as linear sums of principal components has become a widely accepted animation technique. While powerful, the simplest version of this approach is not particularly well suited to modeling the specific style of an individual whose motion had not yet been recorded when building the database: it would take an expert to adjust the PCA weights to obtain a motion style that is indistinguishable from his. Consequently, when realism is required, the current practice is to perform a full motion capture session each time a new person must be considered. In this paper, we extend the PCA approach so that this requirement can be drastically reduced: for whole classes of cyclic and noncyclic motions such as walking, running or jumping, it is enough to observe the newcomer moving only once at a particular speed or jumping a particular distance using either an optical motion capture system or a simple pair of synchronized video cameras. This one observation is used to compute a set of principal component weights that best approximates the motion and to extrapolate in real‐time realistic animations of the same person walking or running at different speeds, and jumping a different distance. 相似文献
106.
E Lledó García C Hernández Fernández G Escribano Pati?o JM Díez Cordero I Moncada Iribarren F Verdú Tartajo F Herranz Amo R Durán Merino J Jara Rascón A Luque A Fernández Escribano A de Palacio Espa?a F González Chamorro 《Canadian Metallurgical Quarterly》1996,20(7):648-654
We present 11 lymphoceles in 180 consecutive kidney transplants (6%). We study the potential etiologic factors, symptoms, diagnostic evaluation and treatment, stressing the role of laparoscopy in management of bulky and loculated symptomatic lymphoceles. This technique allows to reduce morbidity, increasing efficacy and shortening hospitalization. 相似文献
107.
The treatment of orbital complications of nasosinusal processes has seen numerous modifications. Traditionally, cases with purulent collections were treated by external drainage. Currently, the introduction of new optical systems allows such complications to be approached from within the nasal cavity. We report a case of a 3-year-old girl with a subperiosteal orbital abscess secondary to ethmoiditis, which was cured by minimally aggressive endoscopic management and medical treatment. 相似文献
108.
Raquel Ibáñez Marco Peluso Armelle Munnia Sara Piro Carlos A. González Pilar Amiano M. J. Tormo Eva Ardanaz Aurelio Barricarte Antonio Berenguer M. Dolores Chirlaque Miren Dorronsoro Paula Jakszyn Nerea Larrañaga Carmen Martínez Carmen Navarro J. Ramón Quirós M. José Sánchez Antonio Agudo 《European Food Research and Technology》2009,229(4):549-559
The aim of this study was to assess the relationship between bulky DNA adducts in white blood cells (WBC) and lifestyle factors
in a sample from the Spanish cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC). 296 subjects
aged between 35 and 64 years, from five regions, were included. Food intake was estimated with a computerized version of dietary
history questionnaire. Daily intake of polycyclic aromatic hydrocarbons (PAH) was estimated using a database with information
on food content of potential carcinogens. Data on lifestyle and health factors were collected and DNA adducts measured using
the nuclease P1 32P-postlabelling technique. Geometric means of adducts were similar for men and women (4.11/109 and 3.94/109 nucleotides, respectively). Highest levels of adduct were observed in non-smokers and non-occupationally exposed. Meat intake,
oils and fats were associated with higher levels of adducts, but all non-statistically significant. Higher intakes of calcium,
sodium and phosphorus were associated with lower adducts levels. Summarising, our study shows that bulky adducts measured
by 32P-postlabelling in DNA from WBC do not correlate with the usual diet of healthy Spanish adults. Although it has been proposed
that diet be the main source of PAH in nonsmokers without occupational exposure, DNA adducts do not seem to be suitable biomarkers
of dietary PAH in general population. 相似文献
109.
Raquel Vigil de la Villa Moiss Frías María Isabel Snchez de Rojas Iigo Vegas Rosario García 《Applied Clay Science》2007,36(4):279-286
This work reports the project of thermal effects in mineralogy and texture of the paper sludge to employ them as pozzolanic material.For this reason, the chemistry and mineralogical composition has been studied, as well as its morphology by XRD, SEM and EDX.The initial sludge has been treated to 700, 750 and 800 °C during 2 and 5 h being observed that initial kaolinite becomes metakaolinite and that its pozzolanic activity with a paper sludge treated to 700 °C for 2 h is comparable to that of a commercial metakaolinite. The transformation of kaolinite after the dehydroxylation is to convert in amorphous metakaolinite. At the temperature mentioned above, calcite from the initial sludge is maintained active.It is concluded that the pozzolanic activity of metakaolinite is strongly related to the crystallinity of the original kaolinite. Well-ordered kaolinite is transformed into more reactive metakaolinite. 相似文献
110.
A new general method is derived for reduction of linear systems of equations with symbolic polynomial coefficients suitable for using sparse matrix techniques. Its implementation in a program for symbolic analysis of circuits offers significant advantages over the existing reduction method. 相似文献