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21.
The eigenface method that uses principal component analysis (PCA) has been the standard and popular method used in face recognition. This paper presents a PCA - memetic algorithm (PCA-MA) approach for feature selection. PCA has been extended by MAs where the former was used for feature extraction/dimensionality reduction and the latter exploited for feature selection. Simulations were performed over ORL and YaleB face databases using Euclidean norm as the classifier. It was found that as far as the recognition rate is concerned, PCA-MA completely outperforms the eigenface method. We compared the performance of PCA extended with genetic algorithm (PCA-GA) with our proposed PCA-MA method. The results also clearly established the supremacy of the PCA-MA method over the PCA-GA method. We further extended linear discriminant analysis (LDA) and kernel principal component analysis (KPCA) approaches with the MA and observed significant improvement in recognition rate with fewer features. This paper also compares the performance of PCA-MA, LDA-MA and KPCA-MA approaches.  相似文献   
22.
Potential high-risk freshmen for three core courses (BasicMath, Calculus, and Computing) in the university were identified based on the “College Students’ Adjustment Check List (CSACL)” data available with the Student Development Centre in the Office of Students’ Affairs of the university. The study demonstrates that to ameliorate the problem of unpreparedness of freshmen, to check failure rates, and efficient use of limited resources, an effective remedial system could be developed by the combined inputs from the Office of Students’ Affairs, Computer Centre, Academic Affairs, and the Institutional Research. Our study corroborates the findings of other researchers that gender, teacher, department, high school performance, enrolment channel, and loads during remedial course influence the learning outcome. Also, it was found that the use of multi-evaluation approaches in different enrolment channels can attain higher retention rates.  相似文献   
23.
Oxidative stress plays an important role in the development of malarial anemia. The present study was undertaken to study the role of oxidant and antioxidants in the patients ofPlasmodium falciparum malaria (n=25),Plasmodium vivax malaria (n=25) as against the normal control subjects (n=25). The parameters included are the hematological [hemoglobin, erythrocyte adenosine deaminase (ADA) activity, ADP-induced platelet aggregation] and serum total lipid peroxide as an index of oxidative stress and antioxidants [erythrocytic superoxide dismutase (SOD) activity, serum vitamin E] & serum iron. Significant alterations in all above parameters were noted in both groups of malaria patients as compared to control subjects. Maximum significant alterations in hematological parameters were noticed inP. falciparum infection as compared toP. vivax malaria (p<0.001). Substantial rise in serum total lipid peroxides and a significant reduction in antioxidants such as serum vitamin E and serum iron were noted inP. falciparum malaria as compared toP. vivax malaria (p<0.001), whereas maximum decline in erythrocytic SOD activity was observed inP. vivax infection as compared toP. falciparum malaria (p<0.05). Follow-up examination revealed the restoration of the levels of all biochemical parameters to the normal level after 20 days of antimalarial therapy. The study specified severity ofP. falciparum malaria and also functional duality of oxidant.  相似文献   
24.
In a pilot study with five oral cancer patients undergoing radiotherapy (RT) three were given Granulocyte Macrophage Colony Stimulating Factor (GM-CSF) as a protective agent to reduce the mucosal inflammation during radiotherapy. The myeloperoxidase (MPO) enzyme activity in WBC was quantitated. The three patients showed a significant increase in the MPO activity when compared with two untreated controls indicating the efficacy of GM-CSF as a protective agent. It is suggested that further detailed studies with larger number of patients would be useful.  相似文献   
25.
Core and infrastructure business activities are vital to the organization, and are growing more and more dependent on information systems. Theory suggests that more core and infrastructure business activities would inspire more strategic information systems planning which in turn would result in greater planning effectiveness. One hundred thirty chief information officers in manufacturing companies completed a questionnaire about the extent that their organization performed core and infrastructure business activities, and carried out technical, personnel, and procedures planning. The findings showed that infrastructure activities lead to all three types of planning whereas core activities lead only to procedures planning. Moreover, they showed that technical planning leads to planning effectiveness whereas personnel and procedures planning do not. The findings suggest that future researchers might try to uncover the reasons that core activities do not lead to more information systems planning. For practitioners, the findings suggest that managers reconsider how their organizations respond to core and infrastructure needs, and whether they should adjust their information systems planning.  相似文献   
26.
The purpose of this study was to find out the effect of lead exposure on systolic and diastolic blood pressure, heme biosynthesis related and hematological parameters of automobile workers. For this study 30 automobile workers were selected and compared with 30 age matched healthy control subjects. Significantly increased blood lead (364%, P < 0.001) and urinary lead (176%, P < 0.001) levels were observed in automobile workers (study group) as compared to controls. Systolic blood pressure (5.32%, P < 0.05) and diastolic blood pressure (5.87%, P < 0.05) were significantly increased in the automobile workers as compared to controls. The significantly decreased non-activated erythrocyte δ-aminolevulinic acid dehydratase (δ-ALAD) (−18.51%, P < 0.01) and activated δ-ALAD (−13.29%, P < 0.05) levels were observed in automobile workers as compared to normal healthy control subjects. But the ratio of activated/non-activated δ-ALAD was significantly increased (43.83%, P < 0.001) in automobile workers as compared to controls. Excretions of δ-aminolevulinic acid (83.78%, P < 0.001) and porphobilinogen (37%, P < 0.001) in urine were significantly increased in the study group as compared to the controls. In automobile workers heamoglobin (−11.51%, P < 0.001), hematocrit (−4.06%, P < 0.05), mean corpuscle volume (−3.34%, P < 0.05), mean corpuscle hemoglobin (−5.66%, P < 0.01), mean corpuscle hemoglobin concentration (−7.67%, P < 0.001), red blood cell count (−14.6%, P < 0.001) were significantly decreased and total white blood cell count (11.44%, P < 0.05) increased as compared to the controls. The results of this study clearly indicate that the absorption of lead is more in automobile workers and it affects on blood pressure, heme biosynthesis and hematological parameters observed in this study group.  相似文献   
27.
We have studied the expression of lactate dehydrogenase and its isoforms in gall bladder cancer, cholelithiasis and chronic cholecystitis. Quantitative and qualitative assays of lactate dehydrogenase and its various isoforms were carried out in the blood sera of patients and healthy controls along with parallel estimation of various liver function test enzymes. Statistical analysis was done using the software Graph Pad Prism. Significantly high expression of lactate dehydrogenase along with alkaline phosphatase and total bilirubin (P ≤ 0.05) was observed in all the three clinical conditions as compared to controls. LDH showed an increasing trend from stage I to stage IV of GBC indicating a significant positive association with the disease progression. The levels of LDH 3 and 4 isoforms appeared significantly more elevated in GBC than cholelithiasis or chronic cholecystitis. We suggest that a careful estimation of total LDH and its isoforms 3 and 4 alone or along with alkaline phosphatase and total bilirubin during different clinical stages, like chronic cholecystitis, cholelithiasis and GBC, may prove to be a potentially useful biomarker in the prognostic management of gall bladder diseases, specifically GBC.  相似文献   
28.
A number of preparations are available in Ayurved for treatment of anemia and iron deficiency. This study was designed to evaluate efficacy of some of them. Six most commonly used Ayurvedic iron containing preparations (Navayasa Curna, Punarnavadi Mandura, Dhatri Lauha, Pradarantaka Lauha, Sarva-Juara-Hara Lauha and Vrihat Yakrdari Lauha) were given in a dose of 250 mg b.d. for 30 days to six groups of iron deficient anemic patients; each group consisting of 20 patients. A control group was given Allopathic preparation—Irex-12, (containing—ferrous fumarate, vitamin C, folic acid and vitamin B12); 1 capsule daily for 30 days for comparison. All hematological and iron parameters were determined before and after completion of treatment. The results showed that there was statistically significant rise (p<0.001) in all of them—Hb, PCV, TRBC, MCV, MCH, MCHC and plasma iron, percent saturation and plasma ferritin. Total iron binding capacity decreased significantly (p<0.001). The response of most of Ayurvedic preparations was better than Allopathic preparation and there was no side effect as observed with iron salts The Hb regeneration rate was 0.10 g/dl/day for Allopathic preparation; while it was above this value for all Ayurvedic preparations exceptPradarantaka Lauha which was least effective.Sarva-Juara-Hara Lauha was the drug of choice as Hb regeneration with it was highest 0.16 g/dl/day. Upon analysis of Ayurvedic drugs, these results were found to be consistent and correlated with iron content of the preparation.  相似文献   
29.
Oxidants (NADPH oxidase and myeloperoxidase) and antioxidants (GSH,GSH peroxidase, SOD and glucose 6 phosphate dehydrogenase, that provides NADPH for antioxidants) were assayed in the neutrophils from oral cancer patients, in three stages viz, baseline samples,15 days after radiation and 30 days following radiation. These samples were obtained from 2 groups of patients. Group A that received radiation alone and Group B that received radiation and ocimum flavonoids,a radioprotector. The results showed a significant fall in the SOD levels in the second follow up of group B.Glucose 6 phosphate dehydrogenase showed significant increase only in the first follow up of patients who received Ocimum flavonoids. Except for these findings all other parameters remained statistically nonsignificant.  相似文献   
30.
Anatomy is an important component in the vertical integration of basic science and clinical practice. Two common pedagogies are cadaveric dissection and examination of prosected specimens. Comparative studies mostly evaluate their immediate effectiveness. A randomized controlled trial design was employed to compare both the immediate and long-term effectiveness of dissection and prosection. Eighty third-year medical students undergoing their surgical rotation from the Yong Loo Lin School of Medicine were randomized into two groups: dissection and prosection. Each participated in a one-day hands-on course following a similar outline that demonstrated surgical anatomy in the context of its clinical relevance. A pre-course test was conducted to establish baseline knowledge. A post-course test was conducted immediately after and at a one-year interval to evaluate learner outcome and knowledge retention. A post-course survey was conducted to assess participant perception. Thirty-nine and thirty-eight participants for the dissection and prosection groups, respectively, were included for analysis. There was no significant difference between mean pre-course test scores between the dissection and prosection groups [12.6 (3.47) vs. 12.7 (3.16), P > 0.05]. Both the mean immediate [27.9 (4.30) vs. 24.9 (4.25), P < 0.05] and 1 year [23.9 (4.15) vs. 19.9 (4.05), P < 0.05] post-course test scores were significantly higher in the dissection group. However, when adjusted for course duration [dissection group took longer than prosection group (mean 411 vs. 265 min)], these findings were negated. There is no conclusive evidence of either pedagogy being superior in teaching surgical anatomy. Based on learner surveys, dissection provides a greater learner experience.  相似文献   
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