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21.
Abdul Wahid Mir 《AI & Society》2012,27(3):417-420
Students’ Quality Circles (SQCs) are considered in the context of English Language Teaching in Pakistan, with a focus on oral expression. SQCs offer many educational benefits. 相似文献
22.
23.
Elyas Sadeq Alaghbari Zulkarnain Zainal Imad Hamadneh Mohd Zobir Bin Hussein Mohd Haniff Bin Wahid 《Journal of Superconductivity and Novel Magnetism》2012,25(2):255-260
Zn- and Ca-doped ErBa2Cu3O7−δ
were successfully prepared via coprecipitation method using metal acetates as the starting salts. The precipitated samples
were calcined for 20 h at 900 °C and sintered at 920 °C for 24 h. All heat treatments were carried out under oxygen environment.
Results show that there is a selectivity of the doping site depending on the ionic radius of the dopant. Furthermore, increase
in the critical temperature, T
c
, was observed in 0.05 mole of calcium and zinc doped samples. The difference in ionic radius of the dopant led to the increase
in porosity as the ionic radius decreases. On the other hand, structural distortion increased as the difference of ionic radius
became larger. 相似文献
24.
The present investigation examined the effects of placebo (P), low dose (LD), and high dose (HD) ethanol on auditory event-related potential (AEP) recovery functions in a group of males at high risk to develop alcoholism (HR; n = 23, mean = 22.3 years) and a low risk (LR; n = 27, mean = 23.0 years) control group. Condition order was randomized, with one condition (P, LD, or HD) per day and a minimum 1-day interval between conditions. For each subject, both blood alcohol levels (BALs) measured via breathalyzer, and event-related potentials recorded with the entire 10/20 International System, were assessed prior to and at mean intervals of 20, 60, 90, and 130 min after P, LD, or HD administration. A series of binaural auditory stimuli with randomly interposed interstimulus intervals of 0.5, 1.0, and 10.0 sec were used to elicit the N100 and P200 components of the AEP. Between-groups comparisons indicated that ethanol elicited risk group differences in recovery functions not present at baseline. The differences were manifested in the HR group as larger decrements in P200 amplitude during the ascending blood alcohol curve (acute sensitivity) and more rapid returns of both N100 and P200 to baseline levels during the descending blood alcohol curve (acute tolerance). These findings support Newlin and Thomson's (1990) Differentiator Model, suggesting that LR and HR individuals are differentially sensitive to the effects of ethanol. 相似文献
25.
National leprosy control programmes currently face a number of changes to the environment within which they operate. This paper examines the issues arising from these. It focuses, in particular, on those arising from changes in the structure of the health sector as a result of policies of health sector reform which are being considered or adopted in many developing countries. These include decentralization, financing strategies, greater role for the private and NGO sectors and the integration of vertical programmes. The paper is structured around a number of key steps in the development of a strategy for sustainability of appropriate leprosy services. These are the assessment of the epidemiological, social and health services context, development of programme objectives, planning of human and financial resources, development of the strategy, mapping the roles of potential actors, development of regulatory and incentive mechanism, action planning and managing change and, finally, re-evaluation of the programme objectives and service delivery organization. The paper stresses the importance of process in developing ownership of a strategy. It concludes with a set of key questions which it suggests need to be addressed by leprosy programme managers in the development of a proactive response to the changes. 相似文献
26.
EA Hassink AT Brugman-Boezeman LM Robbroeckx PN Rieu EM van Kuyk PM Wels C Festen 《Canadian Metallurgical Quarterly》1998,13(5-6):377-383
Parents play a crucial role in the life of a child suffering from an anorectal malformation (ARM), since their guidance contributes to the degree to which the child learns to cope with his or her disability. We investigated whether they experience stress in parenting such a child and also attempted to identify somatic or behavioral characteristics in the child that influence the stress of parenting. The parents of 109 children (69 males, 40 females; median age 5.9 years, range 1-18 years) with an ARM (58 low, 10 intermediate, 41 high) were studied. The Nijmegen Questionnaire on Child-rearing Situations (NQCS) was used to investigate the existing parenting situation. Behavioral characteristics of the children were studied by means of the Child Behaviour Checklist (CBCL) and the Teacher Report Form (TRF). In a semi-structured interview, we investigated how parents experienced the implications of the disability in everyday life with their child. Our study showed that as far as the perception of parenting stress is concerned, parents of children with an ARM do not differ from those with healthy primary-school children. Within the group of parents with ARM-afflicted children, the parents of older, incontinent children experienced relatively more stress, especially when the child concerned was male. With regard to the children's behavior, the parents and teachers under investigation did not report a higher than normal incidence of deviant behavior. However, when individual parents observed difficult behavior in their child, they found it harder to deal with than the incontinence for feces. Regarding the implications of the disorder for their everyday lives, parents were concerned and indicated a need for specific counselling. We conclude that having a child with a somatic affliction, in this case an ARM, does not automatically imply that the parents experience child-rearing problems. However, certain groups of parents are more at risk, i.e., parents with older, incontinent sons and parents with children exhibiting behavioral problems. In addition, our study shows that parents do have difficulties in coping with the implications of the disorder and express a need for support. We feel that patient care can be improved if aid is tailored to these specific problems. 相似文献
27.
PURPOSE: Despite its common use as an indicator of apoptosis, little is known about the mechanisms controlling apoptotic DNA fragmentation in irradiated cells. This review discusses the pathways of chromatin fragmentation, and the role of both nucleases and chromatin structure in this process. DEFINITIONS: DNA fragmentation linked to apoptosis is a combination of cleavage events excising both large DNA fragments within the range 0.4-1.0 Mbp and 50 kbp followed by random cuts within internucleosomal regions (i.e. DNA laddering). The first two cleavage steps can be detected in virtually all apoptotic cells, but DNA laddering is not ubiquitously observed. Endonucleases that mediate this cleavage of chromatin may be classified by substrate specificity, mode of DNA cleavage and their cofactor requirements. CONCLUSIONS: Three major pathways of DNA fragmentation are proposed and discussed: (1) upregulation of endonucleases, (2) their intranuclear/intracellular redistribution and (3) primary changes of chromatin structure. 相似文献
28.
J Sinkora Z Reháková M Sinkora B Cukrowska H Tlaskalová-Hogenová AT Bianchi B De Geus 《Canadian Metallurgical Quarterly》1998,95(3):443-449
BACKGROUND/AIMS: Deposition of paramagnetic substances in basal ganglia, resulting in increased signals in T1-weighted magnetic resonance images (bright basal ganglia), is frequently seen in liver cirrhosis. The present study describes the prevalence of bright basal ganglia and its clinical significance in patients with long-standing portal vein thrombosis in the absence of liver cirrhosis. METHODS: Six patients with angiographically proven complete portal vein thrombosis and cavernomatous transformation without signs of acute or chronic liver disease were studied by magnetic resonance imaging of the brain, neuropsychiatric evaluation, psychometric tests, electroencephalography, and determination of arterial ammonia levels and of serum manganese concentrations from peripheral venous blood. RESULTS: Five out of six patients demonstrated increased signal intensity in the basal ganglia. Overt portal-systemic encephalopathy was not noted prior to or at the time of evaluation. Normal EEG results were recorded in all patients. Only one of the six patients had pathological results in at least two out of four psychometric tests. This latter patient had had a large right-sided brain infarction. Arterial ammonia concentrations were normal in four of the six patients; one patient with increased ammonia levels had concomitant renal insufficiency with azotemia. The other four patients had no relevant concomitant diseases. Serum manganese levels were non-significantly increased compared with a control group (p=0.06), but they were significantly correlated to basal ganglia signal intensity (R=0.88; p=0.02). CONCLUSIONS: Our results demonstrate that bright basal ganglia primarily represent shunt-induced alterations. They are not directly associated with disturbed liver function nor with portal-systemic encephalopathy. 相似文献
29.
SF Stamatelopoulos NS Saridakis AK Chatzis AT Kalandaridou NM Desses A Lymperidis NM Giannopoulos SD Moulopoulos 《Canadian Metallurgical Quarterly》1998,22(11):993-997
This study examines whether a catheter mounted left intraventricular balloon may prevent left ventricular (LV) dysfunction following acute experimental myocardial infarction. In 10 anesthetized pigs, multiple coronary arterial ligations were applied around the apex of the heart. LV end-diastolic pressure (LVEDP), aortic flow (AF), and LV long and short axis fractional shortening (FS) were measured before and at 15 min intervals after ligations. At the 60th min after ligation, the LV long axis FS and AF decreased by 7.2 +/- 2.6% (p < 0.05) and 13.25 +/- 2.68% (p < 0.01), respectively, and the LVEDP increased by 4.3 +/- 1.1 mm Hg (p < 0.01) while no change was noted in the LV short axis FS. An intraventricular catheter mounted nonpulsating balloon was positioned over the endocardium of the infarcted area at the LV apex. Inflation of the nonpulsating balloon to an optimal volume, which was found to be equal to 8-10% of the LV end-diastolic volume, resulted in a reduction (by 3.8 +/- 1.2 mm Hg, p < 0.01) of the already increased LVEDP and in an increase (by 6.6 +/- 2.1%, p < 0.05) in the LV short axis FS while no statistically significant change was noted in the AF and LV long axis FS. It is concluded that an intraventricular catheter mounted balloon patch positioned over the endocardium of the infarcted area may ameliorate early LV dysfunction, possibly by interfering with the functional geometry of the LV contraction. 相似文献
30.
G- and C-banded karyotypes of Damaliscus hunteri, D. lunatus and D. pygargus were compared using the standard karyotype of Bos taurus. Chromosomal complements were 2n = 36 in D. lunatus jimela, 2n = 38 in D. pygargus phillipsi and D. p. pygargus, and 2n = 44 in D. hunteri. The fundamental number in all karyotypes was 60. Among the three species of Damaliscus, seven autosomal pairs and the X chromosomes were conserved. Y-chromosome differences were attributed to heterochromatic additions or deletions. Banded karyotypes of the two subspecies of D. pygargus exhibited complete homology. Chromosomal complements of D. pygargus and D. lunatus differed by a simple centric fusion. However, karyotypes of D. pygargus and D. lunatus differed from D. hunteri by numerous centric fusions, several of which were related by monobrachial chain complexes. Between the karyotypes of D. hunteri and D. pygargus or D. lunatus, there were two chain complexes, one involving five chromosomes (chain V) and the other involving 12 in pygargus (chain XII) or 13 in lunatus (chain XIII). There were also two simple centric fusions between D. hunteri and D. lunatus/D. pygargus; acrocentric chromosomes 13, 15, 20 and 22 in D hunteri were fused as 13;15 and 20;22 in D. lunatus and D. pygargus. 相似文献