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21.
Two modified minimal realization methods are suggested in this paper for getting reduced order models in time domain with the help of modified Hankel matrices. The methods are computationally simple, efficient and also applicable to Multiple-Input–Multiple-Output (MIMO) systems as well. The proposed methods are validated with the help of a few examples from literature.  相似文献   
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23.
Psoriasis is a common and an inflammatory skin disease. Trace elements play an important role in the skin metabolism such as keratinisation and melanin formation as well as immunological and inflammatory reactions. Henceforth, the present study was aimed to evaluate the essential metals with special reference to Cu and Zn. In this study, 72 psoriatic patients and 50 controls were enrolled. On the basis of PASI score psoriatic group comprising of 48 mild and 24 severe psoriatic patients were grouped. The serum trace elements analysis in the subjects revealed that serum Cu levels and Cu/Zn ratio was significantly higher in the psoriatic patients as compared to controls. Interestingly, severity of the psoriasis was well correlated with the serum Cu levels. Taking together, all these findings suggest that Cu may be a major culprit in the pathogenesis as well as in the severity of the disease.  相似文献   
24.
The mucopolysaccharidoses (MPSs) are a heterogeneous group of rare inherited disorders caused by deficiency of lysosomal enzyme necessary to break down mucopolysaccharides or glycosaminoglycans (GAGs). We had combined clinical findings and ophthalmological features. Biochemical test for urine glycosaminoglycans was done for confirmation of diagnosis in the patient. The case of Sanfillippo’s disease was characterized by delayed development, hyperactivity with aggressive behaviour. Coarse facial feature, hirsutism and sleep disorder. Urine GAG tests for MPS was positive in the case. Based on clinical findings and biochemical tests for MPS, this case was diagnosed as a type III mucopolysaccharidoses. Urinary GAG’s electrophoresis is an important screening test for MPS suspected cases.  相似文献   
25.
Evidence of the value of constructivist theory in the classroom is especially important for educational practice in areas of poverty and social challenge. Research was undertaken in 2010 into the application of constructivist theory on instructional design. The findings of this research are particularly relevant to the current curricular crisis in South Africa which threatens to side-line constructivist priorities and return learners to rote learning from textbooks. The findings are situated here within the national debate over curricular design and instructional models. Placing instructional design within the larger context of national pedagogical contestation provides important evidence of the central role of Freirean imperatives for South Africa’s educational future. This article indicates that a constructivist framework, when pertinently arranged, provides holistic and sustainable procedures for knowledge creation. The findings from the research project showed that, in an environment conducive to learning, learners become self-motivated and better able to master the next phase of the curriculum. As a result of the constructivist framing, participants grew into strategic and effective learners who took responsibility for their own learning. These findings add weight to the call for reconsideration of constructivist foundations in national curriculum design.  相似文献   
26.
The most important objectives that are frequently found in bio-analytical chemistry involve applying tools to relevant medical/biological problems and refining these applications. Developing a reliable sample preparation step, for the medical and biological fields is another primary objective in analytical chemistry, in order to extract and isolate the analytes of interest from complex biological matrices. Since, main inborn errors of metabolism (IEM) diagnosable through uracil analysis and the therapeutic monitoring of toxic 5-fluoruracil (an important anti-cancerous drug) in dihydropyrimidine dehydrogenase deficient patients, require an ultra-sensitive, reproducible, selective, and accurate analytical techniques for their measurements. Therefore, keeping in view, the diagnostic value of uracil and 5-fluoruracil measurements, this article refines several analytical techniques involved in selective recognition and quantification of uracil and 5-fluoruracil from biological and pharmaceutical samples. The prospective study revealed that implementation of molecularly imprinted polymer as a solid-phase material for sample preparation and preconcentration of uracil and 5-fluoruracil had proven to be effective as it could obviates problems related to tedious separation techniques, owing to protein binding and drastic interferences, from the complex matrices in real samples such as blood plasma, serum samples.  相似文献   
27.
The circadian periodicity of plasma lipid peroxide levels and activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were studied in 50 clinically, bacteriologically and radiologically proven fresh cases of pulmonary tuberculosis (age: 21–45 years) and 60 age-matched healthy volunteers with diurnal activity from 06∶00 to about 22∶00 and nocturnal rest. A marked circadian variation in plasma lipid peroxide level was recorded in healthy subjects and pulmonary tuberculosis patients with significant amplitude and acrophase around 16∶21 and 17∶12 respectively. The acrophase tended to be delayed in tuberculosis patients. Furthermore, a statistically significant circadian rhythm was found in SOD, CAT and GPx activities in normal volunteers and pulmonary tuberculopsis patients. SOD and CAT enzyme activity was noted to be maximum at 06∶00 and minimum at 00∶00 in tuberculosis patients. The circadian acrophase for GPx activity was recorded at 16∶15 in normals and around 22∶45 in patients. Moreover, the activity was found to be decreased at all sampling hours during 24-hours sleep-awake period in patients in comparison to healthy counterparts. The MESOR and circadian amplitude also decreased markedly. The decreased activity of measured antioxidant enzymes in pulmonary tuberculosis patients could probably be associated with oxidative stress and/or decreased anti-oxidant defensive mechanism in such patients.  相似文献   
28.
Human cadaveric tissue is the fundamental substrate for basic anatomic and surgical skills training. A qualitative assessment of the use of human cadavers preserved by Thiel's method for a British Association of Urological Surgeons-approved, advanced laparoscopic renal resection skills training course is described in the present study. Four trainees and four experienced laparoscopic surgeons participated in the course. All participants completed a five-point Likert scale satisfaction questionnaire after their training sessions. The quality of cadaveric tissue and the training session were assessed with particular emphasis placed on the ease of patient positioning, the ease of trocar placement, the preservation of tissue planes, the ease of renal pedicle dissection, and the quality of tissue preservation. All of the participants highly rated the quality of the cadaveric tissue embalmed by Thiel's method (mean scores for quality on the five-point Likert scale were 4.5 and 4.3 by the trainees and experienced laparoscopic surgeons, respectively). All of the steps of laparoscopic renal resection were rated 4.0 or more on the Likert scale by both trainees and faculty members. The initial response rates for using a human cadaver embalmed by Thiel's method as a training tool for laparoscopic nephrectomy showed encouraging results. The performance of a laparoscopic nephrectomy on a human cadaver embalmed by Thiel's method bears close resemblance to real laparoscopic nephrectomy procedures, and thus demonstrates added advantages to the previously reported models.  相似文献   
29.
Abstract

Purpose: The fields of competence development and capacity development remain isolated in the scholarship of learning and innovation despite the contemporary focus on innovation systems thinking in agricultural and rural development. This article aims to address whether and how crossing the conventional boundaries of these two fields provide new directions for developing learning and innovation competence in international development.

Design/methodology/approach: Using mixed methods research, this article assesses work environments for experiential learning and innovation, and investigates effective ways of enhancing core competence in agricultural research, education, extension and entrepreneurship.

Findings: Findings suggest that while the focus on input and output indicators are relevant for technological innovation competence development, outcome indicators, such as measures of changes in cognitive, affective and psychomotor domains of learning and innovation, would better serve the purpose of developing organisational and institutional learning and innovation competence.

Practical implications: This research concludes that crossing the conventional boundaries of competence development and capacity development serves as a way to renew the role of education within the innovation systems thinking. However, such an attempt to enhance human capabilities and functionings through education should integrate theory-based, competence-based and experiential learning components as a coherent whole.

Originality/value: This article demonstrates the value of crossing the conventional boundaries of the two seemingly unrelated fields—competence development through education and capacity development through extension—to provide new directions to operationalise innovation systems thinking in agricultural education and extension.  相似文献   
30.
Renal cell carcinoma is the most common form of the kidney cancer accounting for more than 85% of the cases of which clear cell renal cell carcinoma (ccRCC) is the major histological subtype. The central molecular signature for ccRCC pathogenesis is the biallelic inactivation of VHL gene due to the presence of mutations/hyper-methylation/complete gene loss, which results in the downstream HIF activation. These events lead to increased tyrosine kinase receptor signalling pathways (RAS/MEK/ERK pathway, PI3K/AKT/mTOR pathway and NF-κB pathway), which through their downstream effector proteins causes the cell to proliferate and migrate. Recent studies have shown that VHL inactivation alone is not sufficient to induce the tumor. Mutations in numerous other genes that codes for chromatin modifiers (PBRM1, SETD2 and BAP1) and signalling proteins (PTEN and mTOR) have been identified along with activation of alternate signalling pathways like STAT and Sonic Hedgehog (SHH) pathway. It has also been shown that STAT pathway also works cooperatively with HIF to enhance the tumor progression. However, SHH pathway reactivation resulted in tumor regardless of the VHL status, indicating the complex nature of the tumor at the molecular level. Therefore, understanding the complete aetiology of ccRCC is important for future therapeutics.  相似文献   
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