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181.
R. G. Cochrane J. Elkins Dawn M. Richmond 《International Journal of Disability, Development & Education》1969,16(3):131-142
Three hundred and ninety‐nine Grade 4 Brisbane children were given a battery o1 general ability and achievement tests. Means and standard deviations allowed construction of 15‐point scales for a Queensland Grade 4. A correlation matrix included indices concerning sub‐tests of general ability and achievement tests. Comparisons with original A.C.E.R. co‐efficients were made. The matrix was factor sub‐tests of general ability and achievement tests. Comparisons with analysed and rotated, three factors emerging ‐‐ verbal, performance and computational. A canonical correlation was performed and three significant elements emerged ‐‐ a verbal, a computational (or integrative or automatic sequential) and a problem‐solving element. 相似文献
182.
Modeling of D-STATCOM in distribution systems load flow 总被引:1,自引:0,他引:1
HOSSEINI Mehdi SHAYANFAR Heidar Ali FOTUHI-FIRUZABAD Mahmud 《浙江大学学报(A卷英文版)》2007,8(10):1532-1542
This paper presents modeling of Distribution STATCOM (D-STATCOM) in load flow calculations for the steady- state voltage compensation. An accurate model for D-STATCOM is derived to use in load flow calculations. The rating of this device as well as the direction of required reactive power injection for voltage compensation in the desired value (1 p.u.) is de- rived and discussed analytically and mathematically by the phasor diagram method. Furthermore, an efficient method for node and line identification used in load flow calculations is presented. The validity of the proposed model is examined by using two standard distribution systems consisting of 33 and 69 nodes, respectively. The best location of D-STATCOM for under voltage problem mitigation approach in the distribution networks is determined. The results validate the proposed model for D- STATCOM in large distribution systems. 相似文献
183.
184.
Leon IG 《Child development》2002,73(2):652-663
The American definition of kinship based on biological ties, the practice of closed adoption, and stigmas associated with adoption may decisively influence adoption-related losses. Cross-cultural and historical accounts of adoption that do not apply to these contemporary American constructs of parenthood and practices of adoption suggest outcomes that are not as integrally based on loss. Adoption in infancy is defined as parenting a child with one set of (adoptive) parents and two (adoptive and birth) families. Implications for adoption research, policy, and practice are discussed. 相似文献
185.
Do young boys and girls understand what leads to academic success (e.g., talent, effort, good teaching, luck) in the same way? Do young girls and boys have equivalent perceptions of their academic competence? Are these beliefs engendered in the same way across sociocultural contexts? In a cross-cultural study of over 3,000 children in grades 2 to 6, ages 7.2 to 13.6, we discovered that boys and girls around the world have very similar ideas about what generally leads to academic success. Moreover, in the few contexts where boys' and girls' academic performances were equal, their beliefs were also equal. However, when girls outperformed boys, their beliefs in their own talent were no greater than boys' beliefs, even though they did have stronger beliefs than boys in other facets of their achievement potential (e.g., putting forth effort, being lucky, getting their teacher's help). Our findings support the generally close correspondence between children's achievement and their competence-related beliefs, with the exception that young girls appear to specifically discount their talent. The effects held regardless of the children's achievement, intelligence, or age (approximately 8 to 13 years). Girls were more biased in some contexts than in others, however, suggesting that competence-related biases are rooted in culture-specific aspects of school settings. 相似文献
186.
Perception of sign language and its application to visual communications for deaf people 总被引:1,自引:0,他引:1
Video communication systems for deaf people are limited in terms of quality and performance. Analysis of visual attention mechanisms for sign language may enable optimization of video coding systems for deaf users. Eye-movement tracking experiments were conducted with profoundly deaf volunteers while watching sign language video clips. Deaf people are found to fixate mostly on the facial region of the signer to pick up small detailed movements associated with facial expression and mouth shapes. Lower resolution, peripheral vision is used to process information from larger, rapid movements of the signer in the video clips. A coding scheme that gives priority to the face of the signer may be applied to improve perception of video quality for sign language communication. 相似文献
187.
188.
G. N. Raval L. J. Parekh D. D. Patel F. P. Jha R. N. Sainger P. S. Patel 《Indian journal of clinical biochemistry : IJCB》2004,19(2):60-71
Sialic acid, the end moieties of the carbohydrate chains are biologically important and essential for functions of glycoconjugates
and are reported to be altered in cancer patients. Two hundred and twenty five breast cancer (BC) patients, 100 patients with
benign breast disease (BBD) and 100 healthy females (controls) were enrolled for the study. Eight hundred and twenty four
follow-up samples of 225 breast carcinoma patients were also evaluated. The association of sialic acid forms, sialyltransferase
and α-2–6 sialoproteins levels with presence and extent as well as prognosis of breast carcinoma was studied. Serum sialic
acid forms and sialyltransferase revealed significantly elevated levels among untreated breast cancer patients as compared
to the controls, patients with BBD as well as cancer patients in remission. Non-responders showed comparable levels of the
markers with those found in breast cancer patients at the time of diagnosis. Higher levels of sialic acid forms at diagnosis
were associated with poor prognosis. A positive correlation between serum levels of different forms of sialic acids and extent
of malignant disease was observed. The changes in serum proteins with terminal α-2–6 sialic acid correlated well with alterations
in the levels of sialic acid forms and sialyltransferase. Malignant tissues showed elevated levels of sialic acid and sialyltransferase
as compared to surrounding normal tissues.
The results suggested potential utility of these markers in evaluation of clinical outcome. 相似文献
189.
Serap ?uhadar Mehmet K?seo?lu Yasemin ?inpolat Güler Bu?dayc? Murat Usta Tuna Semerci 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2016,26(1):53-60
Introduction
Extremely high glucose concentrations have been shown to interfere with creatinine assays especially with Jaffe method in peritoneal dialysate. Because diabetes is the fastest growing chronic disease in the world, laboratories study with varying glucose concentrations. We investigated whether different levels of glucose spiked in serum interfere with 21 routine chemistry and thyroid assays at glucose concentrations between 17-51 mmol/L.Materials and methods
Baseline (group I) serum pool with glucose concentration of 5.55 (5.44-5.61) mmol/L was prepared from patient sera. Spiking with 20% dextrose solution, sample groups were obtained with glucose concentrations: 17.09, 34.52, and 50.95 mmol/L (group II, III, IV, respectively). Total of 21 biochemistry analytes and thyroid tests were studied on Abbott c8000 and i2000sr with commercial reagents. Bias from baseline value was checked statistically and clinically.Results
Creatinine increased significantly by 8.74%, 31.66%, 55.31% at groups II, III, IV, respectively with P values of < 0.001. At the median glucose concentration of 50.95 mmol/L, calcium, albumin, chloride and FT4 biased significantly clinically (-0.85%, 1.63%, 0.65%, 7.4% with P values 0.138, 0.214, 0.004, < 0.001, respectively). Remaining assays were free of interference.Conclusion
Among the numerous biochemical parameters studied, only a few parameters are affected by dramatically increased glucose concentration. The creatinine measurements obtained in human sera with the Jaffe alkaline method at high glucose concentrations should be interpreted with caution. Other tests that were affected with extremely high glucose concentrations were calcium, albumin, chloride and FT4, hence results should be taken into consideration in patients with poor diabetic control.Key words: assay interference, glucose interference, preanalytical phase, creatinine, Jaffe kinetic assay, thyroid function tests 相似文献190.
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