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151.
Botzan Tudor M. Necula Angelica I. Mariño Miguel A. Başağaoğlu Hakan 《Water Resources Management》1999,13(3):189-203
A competitive irrigated agriculture in the San Joaquin Valley of California, under semiarid to arid climate and repetitive drought conditions, relies on groundwater resources to a great extent. As a result of rapid agricultural development and intense operation of ground water resources over the years, the Valley has been exposed to severe land subsidence and pesticide and fertilizer induced ground water contamination problems. In this paper, based on historical drought recurrences in the region, a model of aridity quantification and climatic scenario for the period 2000–2030 is described. Moreover, a schematic economics model is set up to analyze the potential benefits from artificially recharging the underlying aquifer nearby the San Joaquin River, as compared to the ongoing management plans in the Valley. The approach presented in this paper is based on cost assessment simulation and employs weighting coefficients instead of marketing prices. For the climatic scenario considered in this paper, the comparative benefit-cost analysis reveals significant benefits from artificially recharging the aquifer adjacent to the San Joaquin River. 相似文献
152.
Dayane Alcântara Marcio N. Rodrigues André L. R. Franciolli Erika T. Da Fonseca Fernanda M. O. Silva Rafael C. Carvalho Paula Fratini Carlos Alberto P. Sarmento Antonio José P. Ferreira Maria Angelica Miglino 《Microscopy research and technique》2013,76(8):803-803
The poultry industry is a sector of agribusiness which represents an important role in the country's agricultural exports. Therefore, the study about embryogenesis of the domestic chicken (Gallus gallus domesticus) has a great economic importance. The aim of this study was to evaluate embryonic development of the endoderm in chicken (Gallus gallus domesticus). Forty fertilized eggs of domestic chickens, starting from the 1st day of gestation and so on until the 19 days of the incubation were collected from the Granja São José (Amparo, SP, Brazil). Embryos and fetus were fixed in 10% formaldehyde solution, identified, weighed, measured, and subjected to light and scanning electron microscopy. The endoderm originates the internal lining epithelium of the digestive, immune, respiratory systems, and the organs can be visualized from the second day (48 h) when the liver is formed. The formation of the digestive system was complete in the 12th day. Respiratory system organs begin at the fourth day as a disorganized tissue and undifferentiated. Their complete differentiation was observed at the 10 days of incubation, however, until the 19 days the syrinx was not observed. The formation of immune system at 10th day was observed with observation of the spleen, thymus, and cloacal bursa. The study of the organogenesis of the chicken based on germ layers is very complex and underexplored, and the study of chicken embryology is very important due the economic importance and growth of the use of this animal model studies such as genetic studies. Microsc. Res. Tech. 76:803–810, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
153.
Diaz-Martinez Angelica M.; Interian Alejandro; Waters Deirdre M. 《Canadian Metallurgical Quarterly》2010,20(3):312
Socorro was a 35-year-old Venezuelan woman who attempted suicide by overdose. The psychotherapeutic approach relied on identifying the social context, constructs, and working within Socorro's cultural framework. Cultural issues related to immigration, acculturation, and culturally based gender issues were identified. The integration of cognitive–behavioral, feminist, and multicultural approaches helped to identify how migratory stressors oppressed her sense of self. Tenets of multiracial feminism were incorporated to better understand how her social context affected her perception of relationships, how she made choices and interpreted them. Future work with Latinas should address the development of models for treatment that fuse these perspectives. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
154.
155.
Ilenia Severi Marco Fosca Georgia Colleluori Federico Marini Luca Imperatori Martina Senzacqua Angelica Di Vincenzo Giorgio Barbatelli Fabrizio Fiori Julietta V. Rau Antonio Giordano 《International journal of molecular sciences》2021,22(15)
Hypothalamic dysfunction is an initial event following diet-induced obesity, primarily involving areas regulating energy balance such as arcuate nucleus (Arc) and median eminence (ME). To gain insights into the early hypothalamic diet-induced alterations, adult CD1 mice fed a high-fat diet (HFD) for 6 weeks were studied and compared with normo-fed controls. Transmission and scanning electron microscopy and histological staining were employed for morphological studies of the ME, while Raman spectroscopy was applied for the biochemical analysis of the Arc-ME complex. In HFD mice, ME β2-tanycytes, glial cells dedicated to blood-liquor crosstalk, exhibited remarkable ultrastructural anomalies, including altered alignment, reduced junctions, degenerating organelles, and higher content of lipid droplets, lysosomes, and autophagosomes. Degenerating tanycytes also displayed an electron transparent cytoplasm filled with numerous vesicles, and they were surrounded by dilated extracellular spaces extending up to the subependymal layer. Consistently, Raman spectroscopy analysis of the Arc-ME complex revealed higher glycogen, collagen, and lipid bands in HFD mice compared with controls, and there was also a higher band corresponding to the cyanide group in the former compared to the last. Collectively, these data show that ME β2-tanycytes exhibit early structural and chemical alterations due to HFD and reveal for the first-time hypothalamic cyanide presence following high dietary lipids consumption, which is a novel aspect with potential implications in the field of obesity. 相似文献
156.
Branco E Guimarães JP Miglino MA Lacreta AN Ishizaki MN Gomes BD Muniz JA Imbeloni A Fioretto ET De Lima AR 《Microscopy research and technique》2011,74(6):484-487
Saimiri sciureus is one of the smallest Cebidae native of Amazon region and also found at the biological reserve of northeast Atlantic forest. It is an omnivore animal, with diversified diet that directly influences the lingual mucosa, which includes certain types of papillae with different organization levels. The present study attempted to describe the morphological and ultrastructure aspects of the dorsal surface of the S. sciureus. Five tongues of de S. sciureus were analyzed from three males and two females who died from natural causes and were obtained from breeding colonies of CENP-Ananindeua-PA. Main macroscopic features were a general triangular shape with a craniocaudal elongation pointed apex. Tissue samples--apex, body, and root of tongue--were fixed in modified Karnovsky solution, following standard scanning protocol, mounted in stubs, coated by gold, and analyzed by Scanning Electron Macroscopy (SEM). Four types of papillae were described: filiform (along all tissue extension with 154 μm of diameter), fungiform (along all tissue extension with 272 μm of diameter), vallate [just three units in caudal (dorsal) portion with 830 μm of diameter] and foliate (one pair at caudolateral surface with ~ 13 projections and 3000 μm in length). Data analysis indicates that the distribution and ultra structural morphology of the S. sciureus lingual papillae are some similar to other primates. 相似文献
157.
Maria Angelica Andrade Leite Ivan Luiz Marques Ricarte 《Knowledge and Information Systems》2013,34(3):619-651
More people than ever before have access to information with the World Wide Web; information volume and number of users both continue to expand. Traditional search methods based on keywords are not effective, resulting in large lists of documents, many of which unrelated to users’ needs. One way to improve information retrieval is to associate meaning to users’ queries by using ontologies, knowledge bases that encode a set of concepts about one domain and their relationships. Encoding a knowledge base using one single ontology is usual, but a document collection can deal with different domains, each organized into an ontology. This work presents a novel way to represent and organize knowledge, from distinct domains, using multiple ontologies that can be related. The model allows the ontologies, as well as the relationships between concepts from distinct ontologies, to be represented independently. Additionally, fuzzy set theory techniques are employed to deal with knowledge subjectivity and uncertainty. This approach to organize knowledge and an associated query expansion method are integrated into a fuzzy model for information retrieval based on multi-related ontologies. The performance of a search engine using this model is compared with another fuzzy-based approach for information retrieval, and with the Apache Lucene search engine. Experimental results show that this model improves precision and recall measures. 相似文献
158.
In this work, a class of switching systems known as integrator is studied. Such systems have the feature of being very simple and allow us to gain insight on the effect that the switching sequence has on system stability. Three problems are analyzed. First, the practical stabilizability problem under system uncertainty is studied. Confinement regions are explicitly computed, and switching sequences based on the nominal behavior of the systems are derived. Second, the practical stabilizability problem using output feedback is solved; in this case, sufficient conditions are proposed. Finally, by joining both results, sufficient conditions for practical stabilizability of uncertain systems under output feedback are given. The results are illustrated with examples and some extensions for uncertain linear system and event‐based switching are given. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
159.
Maria Cazacu Mircea Ignat Carmen Racles Angelica Vlad Mihaela Alexandru George Zarnescu 《Polymer International》2009,58(7):745-751
BACKGROUND: Among polymers, elastomers can achieve very large deformations and deliver relatively high forces when an electric field is applied to them. In addition, a number of active components, such as carbon black, multi‐walled nanotubes or metallic powders, can be used to obtain increased effects. One elastomer used as a host for these active fillers is polydimethylsiloxane. RESULTS: Pyrite powders were physically incorporated in a polymeric matrix consisting of interconnected polydimethylsiloxane/silica networks. The mixtures were processed as films by casting on a Teflon substrate before crosslinking. The films thus formed were investigated from the point of view of their mechanical behaviour and were tested as active elements in an actuation system. CONCLUSION: Electromechanical tests of the polymeric membranes under investigation revealed a very good behaviour for applications in nano‐ and micro‐actuation. Some of the prepared films showed significant displacements at reasonable voltages (i.e. 56 000 nm at 460 V or 1000 nm at 6 V). Sensitivities between 2.608 and 333.33 nm V?1 were obtained in inverse dependence on the Young's modulus values. Copyright © 2009 Society of Chemical Industry 相似文献
160.
Casler Krista; Eshleman Angelica; Greene Kimberly; Terziyan Treysi 《Canadian Metallurgical Quarterly》2011,47(3):857
Children sometimes make scale errors, attempting to interact with tiny object replicas as though they were full size. Here, we demonstrate that instrumental tools provide special insight into the origins of scale errors and, moreover, into the broader nature of children's purpose-guided reasoning and behavior with objects. In Study 1, 1.5- to 3.5-year-olds made frequent scale errors with tools in a free-play session. Study 2 utilized a novel forced-choice method, representing a stronger test by handing 2-year-olds a feasible alternative for goal achievement, but children continued to make scale errors. Study 3 confirmed that errors were not based in perceptual immaturity. Results are explained using a framework of teleofunctional (purpose-based) reasoning as a powerful and early developing influence on children's actions. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献