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31.
Electricity has played a pivotal role in the development of Punjab economy. Of late there has been a steep rise in the demand for electricity in the state. The present study undertakes a holistic view of growth of demand for electricity in the state. The technique applied is multiple regression and secondary data is used for the purpose of analysis. The study concludes that demand for electricity in the state is price inelastic but income elastic for majority of consuming sectors. An important policy implication thereof is that price hike will be ineffective in regulating and managing demand unless price is varied in an hourly basis. Therefore, the state has to resort to other demand-side management (DSM) measures, such as improving efficiency of electricity use and its conservation. Considering the high income elasticity of electricity demand, sufficient electricity-generating capacity needs to be created, since demand is expected to grow at an accelerated rate in future. This calls for a comprehensive electricity policy. The study further concludes that in the long run, price-demand as well as income-demand relationship in case of electricity is likely to remain uncertain especially in the post-reform era.  相似文献   
32.
Melt-quenched 15(ZnO,Fe2O3) 50SiO2·20(CaO,P2O5) 15Na2O bioactive glass was heat treated at temperatures (TA) ranging from 550°C to 850°C for different time periods (tA=1, 2 and 3 hours) to understand its devitrification characteristics. Crystallization of calcium sodium phosphate, zinc ferrite, magnetite, and hematite phases depended on heat treatment conditions. Decrease in saturation magnetizations (Ms) with increase in tA of glass heat treated at TA≥750°C is attributed to the formation of hematite which is a weak magnetic material. Magnetic properties as functions of TA and tA are interpreted on the basis of clustering of Fe ions, super-exchange interaction between Fe2+ and Fe3+ ions and formation of ferrimagnetic and weakly magnetic iron oxide phases with different heat treatment conditions. Electron paramagnetic resonance parameters reveal the variations in site distortions and randomness in Fe ion environment in the matrix upon heat treatment. In vitro mineralization ability of the glass-ceramics was evaluated by immersion in simulated body fluid (SBF) and monitoring both the pH variation of SBF and formation of hydroxyapatite surface layer as a function of immersion time. These studies help in assessing these glass-ceramics for hyperthermia treatment and in optimizing the processing conditions for this application.  相似文献   
33.
A novel series of sulfur-containing dihydrochromeno[8,7-e][1,3]oxazine-2(8H)-thiones has been synthesized through an eco-friendly Mannich-type condensation cyclization reaction of 7-hydroxy-4-methyl-2-thiocoumarin or 6-chloro-7-hydroxy-4-methyl-2-thiocoumarin with formaldehyde and primary amines in water at 80–90°C for 2 h. All the synthesized compounds were screened for their in vitro anti-bacterial efficacy against two Gram-positive and three Gram-negative bacterial strains by using the disc diffusion method. The compound (8c) was found to be most potent with the zone of inhibition of 16 and 15 mm against Staphylococcus aureus ATCC 2937 and Klebsiella pneumoniae ATCC 31488, respectively.  相似文献   
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OBJECTIVE: To identify characteristics associated with provision of bystander CPR in witnessed out-of-hospital cardiac arrest cases. METHODS: An observational, prospective, cohort study was performed using cardiac arrest cases as identified by emergency medical services (EMS) agencies in Oakland County. MI, from July 1, 1989, to December 31, 1993. All patients who sustained a witnessed arrest prior to arrival of EMS personnel were reviewed. RESULTS: Of the 927 patients meeting entry criteria, the 229 patients receiving bystander CPR were younger: 60.9 +/- 14.7 vs 67.9 +/- 14.7 years (p < 0.01). Most (76.6%) cardiac arrests occurred in the home. In a multivariate logistic model, only the location of arrest outside the home was a significant predictor of receiving bystander CPR [odds ratio (OR) 3.8; 99% CI 2.5, 5.9]. Arrests outside the home were associated with significantly improved outcome, with 18.2% of out-of-home and 8.2% of in-home victims discharged from the hospital alive (OR 2.5; 99% CI 1.4, 4.4). CONCLUSION: Patients who have had witnessed cardiac arrests outside the home are nearly 4 times more likely to receive bystander CPR, and are twice as likely to survive. This observation emphasizes the need for CPR training of family members in the authors' locale. This phenomenon may also represent a significant confounder in studies of out-of-hospital cardiac arrest and resuscitation.  相似文献   
37.
Various growth factors and basement membrane proteins have been implicated in the pathobiology of astrocytomas. The goal of this study was to determine the relative contribution of these two factors in modulating the phenotype of U-373 MG glioblastoma cells as determined by the expression of the intermediate filament proteins glial fibrillary acidic protein, vimentin, and nestin. For these determinations, cells plated in serum-free medium were treated either with growth factors binding to tyrosine kinase receptors including transforming growth factor-alpha, epidermal growth factor, platelet-derived growth factor-AA, basic fibroblast growth factor, and insulin-like growth factor-1 or with basement membrane proteins including collagen IV, laminin, and fibronectin. The changes in the expression levels of intermediate filament proteins in response to these treatments were analyzed by quantitation of immunoblots. The results demonstrate that collagen IV and growth factors binding to tyrosine kinase receptors decrease the glial fibrillary acidic protein content of U-373 MG cells. Growth factors binding to tyrosine kinase receptors also decrease the vimentin content of these cells but do not affect their nestin content. On the other hand, basement membrane proteins decrease the nestin content of U-373 MG cells but do not affect their vimentin content. The significance of these results with respect to the role played by different factors in modulating the phenotype of neoplastic astrocytes during tumor progression is discussed.  相似文献   
38.
Lei Xu  Papia Sultana  Xuhong Zhou 《Thin》2009,47(6-7):807-815
Presented in this paper is a study involving finite element analysis to investigate the flexural strength of built-up box sections which have been extensively used in residential and commercial construction in North America. In the North American Specification for the Design of Cold-Formed Steel Structural Members [CSA, North American specification for the design of cold-formed steel structural members, S136, Canadian Standard Association, 2002], there is no guideline or design equation to calculate the flexural strength of this type of section. Both the Lightweight Steel Framing Design Manual [CSA, Supplement 2004 to the North American specification for the design of cold-formed steel structural members, S136, Canadian Standard Association, 2004] and Cold-Formed Steel Framing Design Guide [AISI, Cold-formed steel framing design guide", American Iron and Steel Institute, 1st ed., 2002, 2nd ed., 2007] have recommended that the flexural strength and moment of inertia of the built-up sections to be taken as the sum of the two components based on deflection compatibility of the components. However, this design approximation has yet to be justified by experimental or numerical study especially for the cases of eccentric and concentric loading. In this study, the proposed finite element model of the built-up box sections was validated with the experimental tests carried out by Beshara and Lawson [Beshara B, Lawson TJ. Built-up girder screw connection variation flexural tests, Internal Report, Dietrich Design Group, 2002]. The flexural strengths obtained from the finite element analysis were then compared with the nominal strength evaluated based on the current design method in order to assess its suitability. Parametric studies were carried out for more than 30 specimens to identify factors affecting the flexural strength of cold-formed steel built-up box sections. A recommendation is made for current design practice of evaluating the flexural strength of the box section when subjected to eccentric loading.  相似文献   
39.
The selective catalytic reduction of NOx with NH3 in the presence of decane over Cu/ZSM-5 catalysts prepared from H+ and Na+ZSM-5 precursors were investigated. Cu/NaZSM-5 catalyst showed significantly higher NOx conversion compared to Cu/HZSM-5. However, the presence of decane decreased the activity of both the catalysts, due to coke formation. Cu/HZSM-5 catalyst showed a larger decline in NOx conversion with time on stream compared to Cu/NaZSM-5. The higher activity of Cu/NaZSM-5 is attributed, to the promoting effect of Na+ cations in the formation of active Cu+ and nitrite and nitrate intermediates species and retardation of coke formation.  相似文献   
40.
In present study, the schizocarp morphology of 14 species belonging to Apiaceae family has been investigated. Light microscopy (LM) and scanning electron microscopy (SEM) have been utilized to highlight qualitative and quantitative features of studied species. Variations have been observed in macro‐ and micro‐morphological features such as color, shape, symmetry, length, width, apex, epicuticular projections, surface patterns, anticlinal, and periclinal wall patterns. Schizocarp shapes observed were oval, round, triangular, linear, elliptic, and globose. Fruit was either homomorphic or heteromorphic. Crystalloids, stellate hair, multicellular spines, and platelets were mostly observed epicuticular projections. Surface patterns on the fruit surface were striate, rugulate‐striate, reticulate, and striato‐knotted. Both macro‐ and micro‐morphological characters can serve as an important tool in classifying Apiaceae family at various taxonomic ranks. Substantial variations observed can assist as useful constraints at various taxonomic levels as they provide reliable and constant details. Disparities observed in schizocarp features can pave a path for Apiaceae family classification based on phylogenetic and molecular studies.  相似文献   
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