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1.
The method of identifying first order plus time delay transfer function model proposed for unstable systems by Ananth and Chidambaram [Closed loop identification to transfer function model for unstable systems, J. Franklin Inst. 336 (1999) 1055-1061] is modified to avoid the stability problems [Cheres, Parameter estimation of an unstable system with a PID controller in a closed loop configuration, J. Franklin Inst., 2005, accepted for publication] of the method. Two modifications are proposed. In the first modification of the method, the under-determined algebraic equations problem is converted into an optimization problem for calculation of the three parameters of the first order plus time delay (FOPTD) model. A simple method is given for the initial guess values of the model parameters. In the second approach, from the definition of Laplace transform of the output response, a third equation is formulated. The resulted three equations, in terms of the three parameters of the transfer function model, are then numerically solved. Simulation results are given for the second order plus time delay transfer function considered by Cheres 2005 [Parameter estimation of an unstable system with a PID controller in a closed loop configuration, J. Franklin Inst., 2005, accepted for publication]. The responses of the identified models with the same PID controllers are compared with that of the actual system. PID controllers are designed based on the identified models. The closed loop responses of the controllers on the original system are evaluated and compared. The present methods give better control performances.  相似文献   
2.
Tubular damage is a complication associated with nephrotic syndrome and increased levels of urinary enzymes are of significant value in detection of the same. The aim of our study was to evaluate the use of urinary lysozyme and trehalase as markers of tubular dysfunction in nephrotic syndrome. This study assessed 35 nephrotic syndrome patients and 30 healthy controls matched for age and sex. Urine samples were examined at pretreatment and post treatment (8 weeks) stages for proteinuria, lysozyme and trehalase. At pretreatmant stage there was significant increase in urinary lysozyme and trehalase as compared to controls (p<0.001). A good correlation was observed between degree of proteinuria and urinary lysozyme (p<0.001;r=0.80) and trehalase (p<0.001; r=0.74). At the end of 8 weeks of treatment, the patients showed significant decrease in their urinary lysozyme and trehalase activity (p<0.001) but no correlation with degree of proteinuria was observed. Our results indicate that enzymes like lysozyme and trehalase can be used as markers of tubular dysfunction.  相似文献   
3.
The analysis of biochemical parameters in 162 patients with various neoplastic disorders along with 50 normal subjects showed significant rise in serum alkaline phosphatase and lactate dehydrogenase as compared to normal subjects. 21 patients with other monoclonal gammopathies which include infection and immunological diseases were also studied. Parameters such as serum calcium, uric acid, total protein, albumin and globulin were also analyzed in 42 (26%) cases of multiple myeloma, 27 (17%) cases of gastro-intestinal malignancies, 22 (14%) cases of urogenital malignancies, 11 (6%) cases of carcinoma breast, 4 (2%) cases of bone tumors, 21 (12%) cases of other monoclonal gammopathies, including 7 (4%) cases of infection and 14 (8%) cases of immunological diseases. The results indicate use of enzymes alkaline phosphatase and lactate dehydrogenase in neoplastic disorders.  相似文献   
4.
Twenty-four hour urinary albumin excretion (UAE) is considered as gold standard method for albuminuria measurement, but collection of 24-h urine is inconvenient. The aim of present study was to evaluate whether albumin: creatinine ratio (ACR) and urinary albumin concentration (UAC) in different spot urine samples correlate or not with 24-h UAE for screening of microalbuminuria in type 2 diabetic patients. We collected first morning void (FMV), random urine sample (RUS) and 24-h urine, separately on consecutive days from 104 type 2 diabetic patients. ACR and UAC in each spot urine sample compared with 24-h UAE with regard to Pearson correlation coefficient. Pearson’s correlation of albumin: creatinine ratio (ACR) with 24-h UAE was (r = 0.802 and 0.623) in first morning void (FMV) and random urine sample (RUS), respectively. Pearson’s correlation coefficient of urinary albumin concentration (UAC) compared with 24-h UAE was (r = 0.943 and 0.920), in FMV and RUS, respectively, P < 0.01. Results revealed that values in first morning void (FMV) were better correlated with 24-h urinary albumin excretion (UAE), than the values in random urine sample (RUS). We conclude that the first morning void (FMV) may be able to replace 24-h urine collection, preferably urinary albumin concentration (UAC) in the initial screening of microalbuminuria in diabetic patients.  相似文献   
5.
Pratham’s “Read India” initiative is a large-scale intervention to improve basic learning and arithmetic among children in primary school. It was started almost 10 years ago and has evolved considerably over time. Currently, this initiative uses two strategies. The first strategy is to work directly with village communities and local schools to improve children’s learning. “Learning camps” are organized in the local school or community for a period of 6–10 days at a time. Local village volunteers help to teach children who are organized in groups by their level of learning. These camps—intensive bursts of focused instruction—are repeated several times during the year. This model which has been rigourously evaluated shows that children’s learning levels improve significantly. The second strategy is to work with the government. This approach is used when school systems want to partner or collaborate with Pratham for improving basic learning. The key element here too is grouping children and teaching them from their level rather than by their grade. This approach also shows promising results. Independent evaluations and randomized control trials conducted on both models have indicated significant impact. Moving between the present set of conditions in India and past lessons, this case describes a decade-long journey of efforts to change teaching and learning at the ground level as well the efforts to bring about significant shifts in priority at the system level. The “Read India” case presented here contributes knowledge on strategies under which effective pedagogy can be brought to scale. It also discusses challenges of transforming instructional change in a context of low initial capacity at the school and system levels, where attention to rapid expansion of access to school had kept aside for a long time critical questions about teaching quality and learning outcomes. A second contribution of “Read India” to current knowledge on large-scale educational change relates to the role non-government actors such as Pratham can play in bringing effective pedagogy to scale to improve student learning.  相似文献   
6.
The total proteins in human urine have been compared by sulfosalicylic acid, sulfosalicylic acid with sodium sulphate and trichloroacetic acid methods with pyrogallol red molybdate method as there are no studies found quantifying imprecision and bias components. Fresh urine of 36 patients was analyzed by four methods. Imprecision and inaccuracy were determined by repeated analysis and method comparison studies using correlation plots, Bland and Altman, and Passing and Bablok regression analyses respectively. The coefficient of variation was 5.07 % for pyrogallol red molybdate; 6.84 % for sulfosalicylic acid; 3.97 % for sulfosalicylic acid with sodium sulphate and 5.93 % for trichloroacetic acid methods. Bland and Altman analysis showed a bias of 5.8, 1.7 and ?5.4 for pyrogallol red molybdate versus sulfosalicylic acid, sulfosalicylic acid with sodium sulphate and trichloroacetic acid methods respectively. Passing and Bablok regression revealed a constant bias for pyrogallol red molybdate versus all turbidimetric methods but a proportional bias only with trichloroacetic acid method. Sulfosalicylic acid with sodium sulphate method is preferred to sulfosalicylic acid and trichloroacetic acid methods.  相似文献   
7.
8.
Learning to read     
This paper traces the philosophical and programmatic evolution of Pratham's accelerated reading programme ‘Read India’. It outlines the experiences that led to the development of the accelerated reading technique and the organizational contexts in which this approach has been played out.  相似文献   
9.
Tooley,Dixon and Gomathi on private education in Hyderabad: a reply   总被引:1,自引:1,他引:0  
Tooley, Dixon and Gomathi maintain that private unrecognised unaided schools in Hyderabad, India, catering for children of the poor, provide a better level of education than do their government counterparts. We examine this contention and argue first that Tooley et al.’s conceptualisation of education and its benefits is flawed and second that the evidence selected and provided to prove the empirical side of the case is one‐sided and unrepresentative. We conclude that their case remains unproven and that flaws in the argument and its evidence provide no substantial case for their contention.  相似文献   
10.
Osteoporosis encompasses a wide spectrum of conditions associated with imbalance of osteoclastic and osteoblastic activities. The increased activity of osteoclasts leads to increased free radical formation and hence lipid peroxidation. Present study probes into the role of antioxidants as a palliative treatment for osteoporosis. It involved 50 healthy controls and 75 clinically diagnosed osteoporosis patients. Both the groups underwent baseline assessment of biochemical markers viz. osteoblastic markers: serum Alkaline phosphatase. Free or ionic calcium and Inorganic phosphorus, osteoclastic markers: serum Tartarate resistant acid phosphatase and Malondialdehyde and the antioxidant status: serum Superoxide dismutase and Erythrocyte reduced glutathione. The osteoporotic group was then divided into groups A (Vitamin E-Evinal 400 mg), B (Vitamin C-Celin 500 mg), C (Vitamin E+C-Evinal+Celin) for antioxidant supplementation for a period of 90 days. The results reveal that there is significant fall in concentration of serum MDA (p<0.001), TrACP (p<0.01). Improvement in antioxidant status is reflected by significant rise in concentration of serum SOD (p<0.001) and erythrocyte GSH (p<0.001) after 90 days of antioxidant supplementation in osteoporosis. The findings indicate that on the whole bone status improved with prolonged antioxidant vitamin supplementation, which can be used as a palliative treatment for osteoporosis. The efficacy is not affected whether the vitamins are administered singly or conjointly.  相似文献   
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