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排序方式: 共有193条查询结果,搜索用时 15 毫秒
1.
H.C. Reddy C.P. Reddy M.N.S. Swamy V. Ramachandran 《Journal of The Franklin Institute》1982,313(4):197-206
In this paper a method for the realization of RC transfer immittance functions with an unsymmetrical lattice is presented. The method yields minimal capacitor realizations for Z12(s) with no pole at s = 0 and ?y12(s) having no pole at s = ∞. The number of resistors needed are only two more than the minimum needed. 相似文献
2.
Lakshmi Lavanya Reddy Swarup A. V. Shah Alpa J. Dherai Chandrashekhar K. Ponde Tester F. Ashavaid 《Indian journal of clinical biochemistry : IJCB》2016,31(1):87-92
Acute coronary syndrome (ACS) is a term for a range of clinical signs and symptoms suggestive of myocardial ischemia. It results in functional and structural changes and ultimately releasing protein from injured cardiomyocytes. These cardiac markers play a major role in diagnosis and prognosis of ACS. This study aims to assess the efficacy of heart type fatty acid binding protein (h-FABP) as a marker for ACS along with the routinely used hs-TropT. In our observational study, plasma h-FABP (cut-off 6.32 ng/ml) and routinely done hs-Trop T (cutoff 0.1 and 0.014 ng/ml) were estimated by immunometric laboratory assays in 88 patients with acute chest pain. Based on the clinical and laboratory test findings the patients were grouped into ACS (n = 41) and non-ACS (n = 47). The diagnostic sensitivity, specificity, NPV, PPV and ROC curve at 95 % CI were determined. Sensitivity of hs-TropT (0.1 ng/ml), hs-TropT (0.014 ng/ml) and h-FABP were 53, 86 and 78 % respectively and specificity for the same were 98, 73 and 70 % respectively. Sensitivity, specificity and NPV calculated for a cut-off combination of hs-TropT 0.014 ng/ml and h-FABP was 100, 51 and 100 % respectively. These results were substantiated by ROC analysis. Measurement of plasma h-FABP and hs-TropT together on admission appears to be more precise predictor of ACS rather than either hs-Trop T or h-FABP. 相似文献
3.
T. Malati G. Rajani Kumari P. V. L. N. Murthy Ch. Ram Reddy B. Surya Prakash 《Indian journal of clinical biochemistry : IJCB》2006,21(1):34-40
Prostate Specific Antigen (PSA) has emerged as the most applicable and important tumor marker for carcinoma prostate. In the
present study PSA was determined in serum of healthy subjects, patients of benign prostate hypertrophy (BPH) and Carcinoma
Prostate (Ca−P) to evaluate its diagnostic efficiency in day to day management of prostate cancer patients and in differentiating
patients of early prostate cancer from those with BPH. Receiver operating characteristic curve (ROC) revealed 2 ng/ml and
10 ng/ml cut off serum PSA level for BPH and untreated carcinoma prostate patients (Ca−P). An extremely significant increase
(P<0.0001) was observed in mean PSA concentration in BPH patients and adenocarcinoma prostate patients when compared to healthy
males. Clinical relevance of PSA was highlighted by a case study of cancer patient prior to any therapy till death. 相似文献
4.
Chère Campbell Gibson 《The American journal of distance education》2013,27(1):23-36
Abstract Academic self‐concept has been demonstrated to influence student success in distance education. The purpose of this study was to examine the nature of academic self‐concept in distance education and to determine its enhancers and detractors. It was determined that this construct is dynamic and multi‐faceted: the process of both learning as an adult and learning at a distance, as well as the content studied, influences academic self‐concept. Implications for both practice and further research are discussed. 相似文献
5.
6.
Lynn Meltzer Tamar Katzir Lynne Miller Ranjini Reddy Bethany Roditi 《Learning disabilities research & practice》2004,19(2):99-108
This study investigated changes in teachers' and students' perceptions of students' effort, strategy use, and academic difficulties when strategy instruction was infused into the classroom curriculum. The sample consisted of 201 students with learning disabilities, 210 average achievers, and 57 teachers from Grades 4–9 in two urban and suburban communities. After six months of classroom‐based strategy instruction, students with learning disabilities reported more consistent use of strategies with their schoolwork and perceived themselves as struggling less in reading, writing, and spelling. Teachers perceived the students with learning disabilities as more strategic and as applying more effort to their schoolwork. Teachers also perceived their students as showing significant improvements in spelling, regardless of whether they had learning disabilities. These findings extended the results of previous investigations and indicated the small, positive impact of classroom‐based strategy instruction. Further investigations are critical to evaluate the generalizability of these findings. 相似文献
7.
Minerva S. Chávez 《Journal of Latinos & Education》2015,14(4):336-344
This autoethnography posits that my presence as a working-class Chicana obtaining an education in the United States consequently created a Thirdspace environment I recognize as Nepantla. Thirdspace allowed me to navigate urban schooling and elite institutions of higher education. Two narratives demonstrate opposing forms of acquired dominant and nondominant forms of cultural capital to interrogate the value of Thirdspace when considering unique knowledge generated by an insider along the margins. This article articulates that strategic construction of bridges into Nepantla may assist Latino students to successfully navigate the schooling experience and offer the potential to reframe educational discourse. 相似文献
8.
Droplet-based microfluidics has gained extensive research interest as it overcomes several challenges confronted by conventional single-phase microfluidics. The mixing performance inside droplets/slugs is critical in many applications such as advanced material syntheses and in situ kinetic measurements. In order to understand the effects of operating conditions on the mixing performance inside liquid slugs generated by a microfluidic T-junction, we have adopted the volume of fluid method coupled with the species transport model to study and quantify the mixing efficiencies inside slugs. Our simulation results demonstrate that an efficient mixing process is achieved by the intimate collaboration of the twirling effect and the recirculating flow. Only if the reagents are distributed transversely by the twirling effect, the recirculating flow can bring in convection mechanism thus facilitating mixing. By comparing the mixing performance inside slugs at various operating conditions, we find that slug size plays the key role in influencing the mixing performance as it determines the amount of fluid to be distributed by the twirling effect. For the cases where short slugs are generated, the mixing process is governed by the fast convection mechanism because the twirling effect can distribute the fluid to the flow path of the recirculating flow effectively. For cases with long slugs, the mixing process is dominated by the slow diffusion mechanism since the twirling effect is insufficient to distribute the large amount of fluid. In addition, our results show that increasing the operating velocity has limited effects on improving the mixing performance. This study provides the insight of the mixing process and may benefit the design and operations of droplet-based microfluidics. 相似文献
9.
Elisa S. Shernoff Adam J. Lekwa Linda A. Reddy Candace Coccaro 《Journal of educational and psychological consultation》2017,27(4):459-485
The purpose of this qualitative study was to examine teachers’ attitudes and experiences with coaching. This study was conducted in advance of a planned randomized controlled trial of a coaching intervention to better align the model with teachers’ needs and goals. Thirty-four K–5 general (n = 26), special education (n = 6), and educational support staff (n = 2) working in two high-poverty schools participated in focus groups. Interrater reliability between independent coders was high (К = 0.92; range: 0.76–1.0). Thematic analyses identified facilitators and barriers to teacher participation in the planned intervention and were used to improve upon the existing coaching model. Themes focused on advantages and disadvantages to coaching and characteristics of effective coaches and coaching models. Implications of findings for research and practice are discussed. 相似文献
10.