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41.
Alternative splicing (AS) is an important part of regulation of eukaryotic gene expression. BAK1 (Brassinosteroid insensitive1-associated receptor kinase 1) is a specific type of plant serine/threonine protein kinases, and can regulate growth and development and natural immunization. To reveal the responses of sugarcane BAK1 gene to the adverse environment, a ScBAK1 gene and its alternative spliceosome, termed ScBAK1 (GenBank accession number: KP032226) and ScBAK1 S1 (GenBank accession number: KP032227), were cloned from leaf cDNA of Yacheng 05-179 utilizing the methods of electronic cloning and RT-PCR. The open reading frame (ORF) length of ScBAK1/ScBAK1 S1 gene was 1 860bp/1 770bp, encoding 619/589 amino acids residues. The predicted molecular weight of the protein was 69.28 kDa/ 65.76 kDa. Both proteins were located in plasma membrane, estimated as acid, hydrophikic and secretive proteins. Random coil and alpha helix gave priority to extended strand in their secondary structure without beta turn. The most important protein function was cell envelope, secondly biosynthesis of amino acids and cofactors. Real-time quantitative PCR analysis revealed that the expression of sugarcane ScBAK1 S1 gene exhibited the reduced expression trend under smut fungus stress and various abiotic exogenous stresses, including SA, CuCl2, PEG, ABA, NaCl and JA, while the expression of ScBAK1 gene was induced by SA, CuCl2, PEG, NaCl and smut fungus stresses. The phenomenon showed that the absent sequences or amounts of ScBAK1 S1 gene plays a key role in the response of ScBAK1 to the stress of sugarcane smut fungus, osmotic stress and cell growth. The differential expression of ScBAK1 and ScBAK1 S1 lays a foundation for further research on the function of ScBAK1 gene under biotic and abiotic stress.  相似文献   
42.
For a pilot-scale application, pH control in the treatment of highly contaminated dye industrial wastewater containing metallic compounds as the main pollutants has been investigated with a method using adaptive heuristic criticism control (AHCC). Subsequent experimentation on between 12 and 18 l of the wastewater was carried out using statistical experimental design methodology to evaluate the effects of three critical factors: slaked lime (calcium hydroxide, Ca(OH)(2)) concentration, iron chloride (FeCl(3)) concentration and wastewater volume. With these critical factors, the wastewater treatment process is modeled as an appropriate quadratic cost function of the turbidity of the clarified water. The model is optimized with Rosenbrock's method. Response surface topology of the wastewater treatment is given in terms of optimal concentrations of lime water and FeCl(3) and optimal wastewater volume at pH 11.  相似文献   
43.
A bench-scale pilot plant has been developed for the treatment of olive-mill water. The plant is fed in a continuous mode and implements a primary treatment (sand filtering and irradiation with UV-rays) and a secondary treatment (anoxic and aerobic biological treatment). Satisfactory results were obtained and the treated green water falls under the limits of the Italian legislation. Veratric and ferulic acid biodegradation were studied under anoxic conditions in order to verify the requirements for optimal biodegradation. Electronic Publication  相似文献   
44.
/ In 1990, the United States officially entered the era of pollution prevention with passage of the Pollution Prevention Act. This paper analyzes EPA's implementation of the Pollution Prevention Act from its passage in 1990 to the present. It examines the barriers EPA must overcome if it is to effectively integrate pollution prevention into its existing regulatory structure, including impediments created by statutory and organizational structure, the existing relationship between EPA and the groups it regulates, the fragmented implementation scheme of national environmental regulation, the balancing of conflicting demands advanced by powerful interests, industry's economic and technical concerns, and institutional inertia. It also examines issues such as industry commitment, the limits of prevention, and measurement concerns. The findings suggest that EPA's efforts at shifting to a pollution prevention regulatory ethic that holds primacy over pollution control are mixed. Its organizational structure, statutory authority, and incentives system still reflect a single-medium pollution control focus, appropriations for pollution prevention programs and activities are paltry compared to traditional pollution control programs, and participation in the program is voluntary. Yet, the findings also point to some promising programs that are working to institutionalize a pollution prevention regulatory ethic, and many states appear very committed to the concept.KEY WORDS: Pollution prevention; Source reduction; Pollution control; Alternative regulatory design; Barriers to implementation  相似文献   
45.
The author contributed to a short ‘in service’ course for staff engaged on a World Bank upgrading project for Ethiopian housing. The project includes both the building of new houses by self‐build co‐operatives on the periphery of Addis Ababa, and the upgrading of a dense inner city area in conditions of acute deprivation. The paper is a highly personal account of the author's impressions of the value of such initiatives.  相似文献   
46.
In the aftermath of the 1979 revolution, the new administration adopted a number of policies to address the question of land ownership, supply and allocation in order to tackle the acute shortage of housing in the urban areas. In 1982, the Five‐Year Urban Land Act was passed by the Parliament. Subsequently a body called the Urban Land Organisation (ULO) was set up to co‐ordinate the process of land preparation and allocation. The 1982 Urban Land act empowered the government to: (a) expropriate certain categories of abandoned urban land, and (b) to set a temporary time schedule of five years during which the act's work will be monitored.

This paper sets out to examine the policies related to urban land which have been introduced and implemented in the 1980s in Iran.  相似文献   

47.
Bates FL  Killian CD 《Disasters》1982,6(2):92-100
This paper reports on what has happened to earthen structures in 26 Guatemalan communities studied over a 4-year period since the 1976 earthquake. The data were obtained from three waves of personal interviews with 1472 randomly sampled household heads. The results show that adobe, which was the primary housing material before the earthquake was heavily damaged in that event. As a consequence the number of adobe structures and of other earthen structures has been drastically reduced. The people of Guatemala individually and because of agency housing programs have abandoned adobe as a building material and turned to concrete block and wood. Surviving earthen structures have not been improved substantially and remain with largely the same structural features as before the earthquake. The greatest improvement is in the use of comer posts or columns in the walls but most of these are made of untreated crude logs or lumber, subject to rot and termite damage. Little information on aseismic housing seems to have spread either within the earthquake area or in the unaffected areas surrounding it. A program to spread information on how to use adobe in aseismic designs needs to be conducted along with one to assist citizens to aquire the resources necessary to improve the earthquake vulnerability of houses.  相似文献   
48.
The objective of this study is to develop an alternative evaluation index (AEI) in order to determine the priorities of a range of alternatives using both the hydrological simulation program in FORTRAN (HSPF) and multicriteria decision making (MCDM) techniques. In order to formulate the HSPF model, sensitivity analyses of water quantity (peak discharge and total volume) and quality (BOD peak concentrations and total loads) are conducted and a number of critical parameters were selected. To achieve a more precise simulation, the study watershed is divided into four regions for calibration and verification according to landuse, location, slope, and climate data. All evaluation criteria were selected using the Driver–Pressure–State–Impact–Response (DPSIR) model, a sustainability evaluation concept. The Analytic Hierarchy Process is used to estimate the weights of the criteria and the effects of water quantity and quality were quantified by HSPF simulation. In addition, AEIs that reflected residents' preferences for management objectives are proposed in order to induce the stakeholder to participate in the decision making process.  相似文献   
49.
Rural, forested areas throughout the United States are experiencing strong housing growth with potentially detrimental impacts on the environment. In this paper, we quantify housing growth in Northern Wisconsin over the last sixty years to determine if growth rates were higher near public lands, which may represent an important recreational amenity. We used data from the U.S. Census to produce decadal housing density estimates, “backcasts,” from 1940 to 2000 for northern Wisconsin to examine “rural sprawl” in northern Wisconsin and its relationship to forested areas and public lands. We integrated housing density estimates with the 1992/1993 National Land Cover Dataset to examine the relationship between rural sprawl and land cover, especially forests. Between 1940 and 2000, private land with <2 housing units/km2 decreased from 47% to 21% of the total landscape. Most importantly, housing growth was concentrated along the boundaries of public lands. In 14 of the 19 counties that we studied, housing growth rates within 1 km of a public land boundary exceeded growth rates in the remainder of the county, and three of the five counties that did not exhibit this pattern, were the ones with the least amount of public land. Future growth can be expected in areas with abundant natural amenities, highlighting the critical need for additional research and effective natural resource management and regional planning to address these challenges.  相似文献   
50.
Titanium dioxide is the most important photocatalysts used for purifying applications. If a TiO2- containing material is left outdoors as a form of flat panels, it is activated by sunlight to remove harmful NOx gases during the day. The photocatalytic efficiency of a TiO2-treated mortar for removal of NOx was investigated in the frame of this work. For this purpose a fully equipped monitoring system was designed at a pilot site. This system allows the in situ evaluation of the de-polluting properties of a photocatalytic material by taking into account the climatologic phenomena in street canyons, accurate measurements of pollution level and full registration of meteorological data The pilot site involved three artificial canyon streets, a pollution source, continuous NOx measurements inside the canyons and the source as well as background and meteorological measurements. Significant differences on the NOx concentration level were observed between the TiO2 treated and the reference canyon. NOx values in TiO2 canyon were 36.7 to 82.0% lower than the ones observed in the reference one. Data arising from this study could be used to assess the impact of the photocatalytic material on the purification of the urban environment.  相似文献   
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