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Growing economies have the dual challenge of economical and industrial growing, but in a sustainable way and with protection of Ecosystems, all prior requirements are a must that are either satisfied or Human Kind will suffer the irreparable loss of Earth Biosphere. Prospective studies show that for the period 1990–2010 the petroleum will be heavier and richer in sulphur. In order to make a more sustainable use of Mexican heavy petroleum the actual “Life Cycle” of Mexican Bottom of Barrel crude oil can be modified through the proposal of producing an activated carbon (CAFOB) from Mexican petroleum vacuums residue and Mexican petroleum coke applied in the flue gases desulphuration, therefore, experimental activated carbon was made from Mexican petroleum vacuums residue and petroleum coke and desulphuration adsorption tests of a synthetic flue gas mixture similar in composition to flue gases produced from the burning of Mexican heavy fuel oil were made. Commercial activated carbons were used as reference materials. The CAFOB180M experimental activated carbon showed a good desulphuration capacity compared to commercial activated carbon, showing its potentiality in the process of evolving the actual “Life Cycle” of Mexican Bottom of Barrel crude oil to a more sustainable one.  相似文献   
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Modern construction has been characterized as a complex and fragmented process. These characteristics have produced a decrease in the quality and cost efficiency of projects. It has been proven that this problem can be partially overcome by implementing constructability, which is based on the integration of construction knowledge into design (as was done in the past). The implementation of constructability is not easy because it represents a change in the way things have been done in the last century. Prior research has found a lack of constructability efforts among participants in the construction industry, especially general contractors. Because builders can play an important role in implementing constructability, this paper assesses constructability practices among general contractors. The data were obtained from a mailed survey. It was found that contractors applied constructability concepts and participated during the earliest phase of the projects more often than is thought. In addition, the findings showed that constructability practices differed depending on the characteristics of the organization, the type of work performed, and the type of contractual arrangement.  相似文献   
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OBJECTIVES: To assess the in vitro adherence of Candida albicans to heat-cured hard and soft denture-base materials with varying surface roughness, and to observe the effect of a mixed salivary pellicle on candidal adhesion to these surfaces. METHODS: In vitro adhesion assays on heat-cured acrylic resin (Trevalon), Molloplast B and Novus using the type strain of C. albicans (NCPF 3153A). Surfaces for the assays were prepared using clinically appropriate rotary instruments. Unstimulated, pooled and clarified whole saliva was used to assess its effect on adhesion. RESULTS: Significantly greater adhesion of C. albicans to rough rather than smooth surfaces was found (P < 0.001), as well as increased adhesion to the machined soft lining materials compared with acrylic. Pre-coating denture-base materials with saliva reduced candidal adhesion on all materials. CONCLUSIONS: Rough surfaces on denture-base materials promote the adhesion of C. albicans in vitro. However, saliva reduces adhesion of C. albicans and thus diminishes the effect of surface roughness and free surface energy differences between materials.  相似文献   
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Extended the research of F. L. Schmidt et al (see record 1976-29035-001) and P. R. Sackett and B. E. Wade (see record 1983-31752-001), who examined the n-size requirements for validity studies to reach a specified level of power under 2 forms of restriction of range to include 2 different types of range restriction (bidimensional direct truncation and combined indirect and direct truncation). Results indicate that sample size requirements are more stringent under these 2 paradigms than under unidimensional direct truncation as applied by Schmidt et al or unidimensional indirect truncation as applied by Sackett and Wade. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Survey data from 113 female physicians, 634 male physicians, and 41 female dentists were compared. Instruments designed to assess work satisfaction, work stress, marital satisfaction, family competence, and psychiatric symptoms and treatment were used, thereby exploring important life domains concurrently. The results suggest that female physicians are much more like both male physicians and female dentists than anticipated. Generally, female physicians describe high levels of work satisfaction, moderate levels of work stress, average-to-high levels of marital satisfaction, and relatively low levels of psychiatric distress. Their lower levels of practice income remain something of an enigma as gender remains the most powerful predictor of income and is not replaced in statistical analyses by specialty, hours worked, or other significant variables. Finally, female physicians who find higher levels of satisfaction in work also report higher levels of marital satisfaction and fewer psychiatric symptoms. For these women, a highly satisfying medical career does not apparently need to be experienced at the cost of marital or personal distress.  相似文献   
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