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11.
Body donation is important for medical education and academic research. However, it is relatively rare in Hong Kong when compared with many Western countries. Comprehensive research has been performed on the motivation for body donation in Western countries; however, there is still insufficient research on body donation in Hong Kong to provide information on how to increase the body‐donation rate. To understand the factors involved in the decision to donate one's body, the authors interviewed a registered donor and the daughter of another donor in Hong Kong. The authors interpreted the information collected in light of the available published reports, which mostly focus on body donation in Western countries. Despite the consistency of some demographic factors and motivations between the participants in our study and those investigated in the published reports from Western countries, there are differences in education level and socioeconomic status between the donors in our study and those from Western studies. The authors also suggest that Confucianism and Buddhism in Chinese culture may motivate potential body donors in Hong Kong. Other important factors that influence the body‐donation decision may include family members' body donation, registration as organ donors, and good doctor–patient relationships. Although case report studies have their limitations, this study allows us to explore the complexity of events and establish the interconnectivity of factors involved in body donation, which could not be achieved in previous survey‐based studies. © 2012 American Association of Anatomists.  相似文献   
12.
Research on students’ views on nature of science (VNOS) in Asian countries such as China is notably lacking. This study aimed to develop and validate an instrument to measure South China high school students’ VNOS. Based on the previously acquired qualitative data, the instrument included seven VNOS dimensions which reflect the crucial aspects of NOS indicated by the literature and/or the dominating ideology in China (i.e., Marxism). A sample (N = 604) was randomly divided into two groups used for exploratory analyses and confirmatory analyses. The results indicated that the instrument expressed satisfactory reliability and validity and the seven NOS dimensions could be explained by a higher-order dimension. That is, the data of this study supported the multi-dimensional framework that treats VNOS as comprising several more-or-less correlated dimensions. Two distinct dimensions, namely “Accumulative-Empirical Source” and “Pragmatic Justification” which have not been explicitly specified in the past literature, were found. In addition, the Chinese high school students generally held a constructivist/relativist-oriented view of all seven dimensions. Differences in gender and grade level were hardly observed in any dimension of the instrument. The findings are further discussed through a socio-cultural lens to enrich the current understanding of VNOS.  相似文献   
13.

Objective

Heavy ion beam, which has emerged as a new mutagen in the mutation breeding of crops and ornamental plants, is expected to result in the induction of novel mutations. This study investigates the morphological and biochemical responses of Oryza sativa toward different doses of carbon ion beam irradiation.

Methods

In this study, the dry seeds of O. sativa were irradiated at 0, 20, 40, 60, 80, 100, and 120 Gy, followed by in-vitro germination under controlled conditions. Morphological and biochemical studies were conducted to investigate the morphological and physiological responses of O. sativa towards ion beam irradiation.

Results

The study demonstrated that low doses (10 Gy) of ion beam have a stimulating effect on the height, root length, and fresh weight of the plantlets but not on the number of leaves. Meanwhile, doses higher than 10 Gy caused reductions in all the morphological parameters studied as compared to the control samples. The highest total soluble protein content [(2.11±0.47) mg/g FW] was observed in plantlets irradiated at 20 Gy. All irradiated plantlets were found to have 0.85% to 58.32% higher specific activity of peroxidase as compared to the control samples. The present study also revealed that low doses of ion beam (10 and 20 Gy) had negligible effect on the total chlorophyll content of O. sativa plantlets while 40 Gy had a stimulating effect on the chlorophyll content. Plantlets irradiated between 40 to 120 Gy were shown to be 0.38% to 9.98% higher in total soluble nitrogen content which, however, was not significantly different from the control samples.

Conclusions

Carbon ion beam irradiation administered at low to moderate doses of 10 to 40 Gy may induce O. sativa mutants with superior characteristics.  相似文献   
14.
澳门特区自2007~2008学年开始实施15年免费教育,即9年义务教育、3年高中教育和3年学前教育免费.研究者运用网络调查及访谈法,对澳门特区免费幼儿教育政策进行研究,结果发现:(1)免费幼儿教育政策只适用于6家公办幼儿园和42家加入免费教育学校系统的私立幼儿园.(2)7家未加入免费教育学校系统的私立幼儿园需缴学费、补充服务费和选择性服务费,但可获政府发放的学费津贴和书簿费.家长很满意这一政策,并表示愿意继续送孩子上收费的私立幼儿园.(3)受访园(校)长、家长及教师对澳门的免费幼儿教育政策都很满意,教师特别满意政府推出的幼儿园教师津贴.(4)免费幼儿教育政策对私立园所的影响有所不同:有些私立园所为了生存而选择加入免费教育学校系统,有些私立园所则为了校政自主而选择不加入免费教育学校系统.客观上,高收费门槛令不同阶层家庭的幼儿自然分流.  相似文献   
15.
This study explored the differences in high school students’ scientific epistemological beliefs (SEBs), motivation in learning science (MLS), and the different relationships between them in Taiwan and China. 310 Taiwanese and 302 Chinese high school students’ SEBs and MLS were assessed quantitatively. Taiwanese students generally were more prone to believe that scientific reality is invented, the development of scientific knowledge is culture-dependent, and scientific knowledge is always changing and its status is tentative than the Chinese students were. Yet, the Taiwanese students perceived higher test anxiety in science than the Chinese students did. Moreover, Chinese students who have a stronger belief that science knowledge is changing and tentative are more likely to perceive themselves as having higher test anxiety in science. The results suggest that the role of culture might have an impact on students’ SEBs and their MLS.  相似文献   
16.
This paper presents a sampled-data predictive control strategy for a class of uncertain continuous-time Markovian jump linear system (MJLS) with time-varying delay. The system under consideration covers MJLS with completely known jump rates and arbitrary switched linear system. The predictive formulation utilizes both off-line and on-line optimization paradigms. The feasibility of the control scheme and the stability of the closed-loop system are investigated by introducing a modified stochastic invariant ellipsoid. The conditions for the existence of a stabilizing optimal controller for the underlying system are obtained via the semi-definite programming (SDP). A numerical example is given to verify efficiency and potential of the developed approach.  相似文献   
17.

Objective

This study examined the anti-adipogenic effects of extracts of Ficus deltoidea var. deltoidia and var. angustifolia, a natural slimming aid, on 3T3-L1 adipocytes.

Methods

Methanol and water extracts of leaves of the F. deltoidea varieties were analyzed to determine their total flavonoid content (TFC) and total phenolic content (TPC), respectively. The study was initiated by determining the maximum non-toxic dose (MNTD) of the methanol and water extracts for 3T3-L1 preadipocytes. Possible anti-adipogenic effects were then examined by treating 2-d post confluent 3T3-L1 preadipocytes with either methanol extract or water extract at MNTD and half MNTD (1/2MNTD), after which the preadipocytces were induced to form mature adipocytes. Visualisation and quantification of lipid content in mature adipocytes were carried out through oil red O staining and measurement of optical density (OD) at 520 nm, respectively.

Results

The TFCs of the methanol extracts were 1.36 and 1.97 g quercetin equivalents (QE)/100 g dry weight (DW), while the TPCs of the water extracts were 5.61 and 2.73 g gallic acid equivalents (GAE)/100 g DW for var. deltoidea and var. angustilofia, respectively. The MNTDs determined for methanol and water extracts were (300.0±28.3) and (225.0±21.2) μg/ml, respectively, for var. deltoidea, while much lower MNTDs [(60.0±2.0) μg/ml for methanol extracts and (8.0±1.0) μg/ml for water extracts] were recorded for var. angustifolia. Studies revealed that the methanol extracts of both varieties and the water extracts of var. angustifolia at either MNTD or 1/2MNTD significantly inhibited the maturation of preadipocytes. Conclusions: The inhibition of the formation of mature adipocytes indicated that leaf extracts of F. deltoidea could have potential anti-obesity effects.  相似文献   
18.
Journal of Educational Change - The quasi-market condition of education intensified the need to seek ongoing school improvements, manage uncertainty, and innovate school-wide pedagogy and...  相似文献   
19.
This study aims to elucidate the antiproliferative mechanism of hydroxychavicol(HC).Its effects on cell cycle,apoptosis,and the expression of c-Jun N-terminal kinase(JNK)and P38 mitogen-activated protein kinase(MAPK)in HT-29 colon cancer cells were investigated.HC was isolated from Piper betle leaf(PBL)and verified by high-performance liquid chromatography(HPLC),nuclear magnetic resonance(NMR),and gas chromatography-mass spectrometry(GC-MS).The cytotoxic effects of the standard drug 5-fluorouracil(5-FU),PBL water extract,and HC on HT-29 cells were measured after 24,48,and 72 h of treatment.Cell cycle and apoptosis modulation by 5-FU and HC treatments were investigated up to 30 h.Changes in phosphorylated JNK(pJNK)and P38(pP38)MAPK expression were observed up to 18 h.The half maximal inhibitory concentration(IC50)values of HC(30μg/mL)and PBL water extract(380μg/mL)were achieved at 24 h,whereas the IC50of 5-FU(50μmol/L)was obtained at 72 h.Cell cycle arrest at the G0/G1 phase in HC-treated cells was observed from12 h onwards.Higher apoptotic cell death in HC-treated cells compared to 5-FU-treated cells(P<0.05)was observed.High expression of pJNK and pP38 MAPK was observed at 12 h in HC-treated cells,but not in 5-FU-treated HT-29 cells(P<0.05).It is concluded that HC induces cell cycle arrest and apoptosis of HT-29 cells,with these actions possibly mediated by JNK and P38 MAPK.  相似文献   
20.
This study investigates the similarities and differences between high school students from Taiwan and China in terms of their scientific epistemological views. In addition, the effects of age and gender on scientific epistemological views were also examined. The results indicate that the students from these two localities, which signify two similar yet different cultures, are substantially different in five out of the six dimensions. Age and gender were also found to have significant effects in some dimensions. Implications for future research were discussed at the end of the paper.  相似文献   
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