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41.
Book reviews     
Summary The review article (with a selected bibliography) annotates, on the basis of Grotjahn'sLinguistische und statistische Methoden in Metrik und Textwissenschaft, some general methodological aspects of statistical methods in the analysis of literary texts and evaluates the attempt in metrical theory, to reconstruct the so-called ‘metrical competence’ with probabilistic evaluated metrical rules in the frame of a generative approach. Leopoldo Sáez-Godoy is a lecturer in Spanish in the Romance Seminar of the University of Bonn, chairman of the Specialist Group for Spanish Texts (ALLC), and member of the bibliography committee of this journal. recently editedFirst Person Female American, an annotated bibliography of autobiographies (Whitston, 1980), and has published articles on SF treatment of computers in government, dystopian uses of IQ testing, and Zamiatin'sWe.  相似文献   
42.
This article describes how the city of El Paso, Texas, initially used an application service provider (ASP) model, allowing the city to fast track its enterprise resource planning (ERP) system implementation. After a change in the ASP arrangements led to less responsiveness to its needs, the city government moved to a self-hosted ERP system. Lessons learned in the evolution from ASP hosting to self-hosting of the city's ERP system are compared to previously published literature.  相似文献   
43.
Fetal alcohol spectrum disorder is the main preventable cause of intellectual disability in the Western world. Although binge drinking is the most studied prenatal alcohol exposure pattern, other types of exposure, such as the Mediterranean, are common in specific geographic areas. In this study, we analyze the effects of prenatal alcohol exposure in binge and Mediterranean human drinking patterns on placenta and brain development in C57BL/6J mice. We also assess the impact of prenatal treatment with the epigallocatechin-3-gallate antioxidant in both groups. Study experimental groups for Mediterranean or binge patterns: (1) control; (2) ethanol; (3) ethanol + epigallocatechin-3-gallate. Brain and placental tissue were collected on gestational Day 19. The molecular pathways studied were fetal and placental growth, placental angiogenesis (VEGF-A, PLGF, VEGF-R), oxidative stress (Nrf2), and neurodevelopmental processes including maturation (NeuN, DCX), differentiation (GFAP) and neural plasticity (BDNF). Prenatal alcohol exposure resulted in fetal growth restriction and produced imbalances of placental angiogenic factors. Moreover, prenatal alcohol exposure increased oxidative stress and caused significant alterations in neuronal maturation and astrocyte differentiation. Epigallocatechin-3-gallate therapy ameliorated fetal growth restriction, attenuated alcohol-induced changes in placental angiogenic factors, and partially rescued neuronal nuclear antigen (NeuN), (doublecortin) DCX, and (glial fibrillary acidic protein) GFAP levels. Any alcohol consumption (Mediterranean or binge) during pregnancy may generate a fetal alcohol spectrum disorder phenotype and the consequences may be partially attenuated by a prenatal treatment with epigallocatechin-3-gallate.  相似文献   
44.
Bovine ruminal fluid (BRF) bioaugmented with Clostridium acetobutylicum (Clac) was assessed for hydrolyzing cellulose and produce biohydrogen (BioH2) simultaneously from pretreated corncob in a single step, without the use of external hydrolytic biocatalysts. The corncob was pretreated using three thermochemical methods: H2SO4 2%, 160 °C; NaOH 2%, 140 °C; NaOCl 2%, 140 °C; autohydrolysis: H2O, 190 °C. Subsequently, BioH2 production was carried out using the pretreated material with the highest digestibility applying a Taguchi experimental array to identify the optimal operating conditions. The results showed a higher glucose released from pretreated corncob with H2SO4 (134.7 g/L) compared to pretreated materials by autohydrolysis, NaOH and NaOCl (123 g/L, 89.8 g/L and 52.9 g/L, respectively). The mixed culture was able to hydrolyze the pretreated corncob and produce 575 mL of H2 (at 35 °C, pH 5.5, 1:2 ratio of BRF:Clac and 5% of solids loading) equivalent to 132 L H2/Kg of biomass.  相似文献   
45.
Candida tropicalis is an emergent pathogen with a high rate of mortality associated with it; however, less is known about its pathogenic capacity. Biofilm formation (BF) has important clinical repercussions, and it begins with adherence to a substrate. The adherence capacity depends principally on the cell surface hydrophobicity (CSH) and, at a later stage, on specific adherence due to adhesins. The ALS family in C. tropicalis, implicated in adhesion and BF, is represented in several CTRG genes. In this study, we determined the biofilm-forming ability, the primary adherence, and the CSH of C. tropicalis, including six isolates from blood and seven from urine cultures. We also compared the expression of four CTRG ALS-like genes (CTRG_01028, CTRG_02293, CTRG_03786, and CTRG_03797) in sessile versus planktonic cells, selected for their possible contribution to BF. All the C. tropicalis strains were biofilm producers, related to its filamentation capacity; all the strains displayed a high adherence ability correlated to the CSH, and all the strains expressed the CTRG genes in both types of growth. Urine isolates present, although not significantly, higher CSH, adherence, and biofilm formation than blood isolates. This study reveals that three CTRG ALS-like genes—except CTRG_03797—were more upregulated in biofilm cells, although with a considerable variation in expression across the strains studied and between the CTRG genes. C. tropicalis present a high biofilm capacity, and the overexpression of several CTRG ALS-like genes in the sessile cells suggests a role by the course of the biofilm formation.  相似文献   
46.
Olive fruits of three of the most important Spanish and Italian cultivars, ‘Picual’, ‘Hojiblanca’ and ‘Frantoio’, were harvested at bi‐weekly periods during three crop seasons to study their development and ripening process. Fresh and dry weights and ripening index were determined for fruit, while dry matter, oil and moisture contents were determined in both fruit and pulp (flesh). Fruit growth rate and oil accumulation were calculated. Each olive cultivar showed a different ripening pattern, ‘Hojiblanca’ being the last one to maturate. Fruit weight increased, decreasing its growth rate from the middle of November. Dry matter and moisture contents decreased during ripening in pulp and fruit, ‘Hojiblanca’ showing the highest values for both. Oil content, when expressed on a fresh weight basis, increased in all cultivars, although for the last time period showed variations due to climatic conditions. During ripening, oil content on a dry weight basis increased in fruit, but oil biosynthesis in flesh ceased from November. Olive fruits presented lower oil and higher dry matter contents in the year of lowest rainfall. Therefore fruit harvesting should be carried out from the middle of November in order to obtain the highest oil yield and avoid natural fruit drop. Copyright © 2004 Society of Chemical Industry  相似文献   
47.
48.
Matching dependencies (MDs) are used to declaratively specify the identification (or matching) of certain attribute values in pairs of database tuples when some similarity conditions on other values are satisfied. Their enforcement can be seen as a natural generalization of entity resolution. In what we call the pure case of MD enforcement, an arbitrary value from the underlying data domain can be used for the value in common that is used for a matching. However, the overall number of changes of attribute values is expected to be kept to a minimum. We investigate this case in terms of semantics and the properties of data cleaning through the enforcement of MDs. We characterize the intended clean instances, and also the clean answers to queries, as those that are invariant under the cleaning process. The complexity of computing clean instances and clean query answering is investigated. Tractable and intractable cases depending on the MDs are identified and characterized.  相似文献   
49.
From 2003 to 2004, we studied the impact of environmental influences on the microbiological quality of a hydroponic tomato farm. The presence of Salmonella was investigated on 906 samples of tomatoes and 714 environmental samples. The farm comprised 14 greenhouses and a technologically advanced packinghouse, and operated under a sanitary agricultural practices plan. The objective of the present study was to determine the operating sources of contamination. During the course of the study, two independent natural events affected the farm. In 2003, water runoff entered some of the greenhouses. A year later, wild animals (opossums, mice, and sparrows) gained entry into several of the greenhouses. Salmonella and Escherichia coli were found in samples of tomatoes, water puddles, soil, shoes, and the feces of local wild and farm animals. Salmonella Montevideo, Salmonella Newport, and strains of the F serogroup were isolated from tomatoes. Almost all of the Salmonella Newport strains were isolated from samples collected during or immediately after the flood. Analysis by pulsed-field gel electrophoresis revealed that some Salmonella Montevideo isolates from tomatoes, opossums, and mice displayed identical XbaI or AvrII patterns, suggesting that these wild animals represented one source of contamination. F serogroup strains were found mostly on samples of goat feces and personnel shoes when standard working practices were in place. Shoes were found to be an important vehicle for dissemination of Salmonella into the greenhouses. The level of protection provided by hydroponic greenhouses does not exclude the eventuality that enteric pathogenic bacteria can gain access through various avenues.  相似文献   
50.
Controlling the porosity, the shape, and the morphology of Kirkendall hollow nanostructures is the key factor to tune the properties of these tailor‐made nanomaterials which allow in turn broadening their applications. It is shown that by applying a continuous oxidation to copper nanowires following a temperature ramp protocol, one can synthesize cuprous oxide nanotubes containing periodic copper nanoparticles. A further oxidation of such nanoobjects allows obtaining cupric oxide nanotubes with a bamboo‐like structure. On the other hand, by applying a sequential oxidation and reduction reactions to copper nanowires, one can synthesize hollow nanoobjects with complex shapes and morphologies that cannot be obtained using the Kirkendall effect alone, such as necklace‐like cuprous oxide nanotubes, periodic solid copper nanoparticles or hollow cuprous oxide nanospheres interconnected with single crystal cuprous oxide nanorods, and aligned and periodic hollow nanospheres embedded in a cuprous oxide nanotube. The strategy demonstrated in this study opens new avenues for the engineering of hollow nanostructures with potential applications in gas sensing, catalysis, and energy storage.  相似文献   
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