As one of the world well-known high-stakes tests, CET-4 （College English Test Band 4） changed from being generally accepted to being widely questioned in the past 25 years. In spite of a series of reforms of CET-4, ...As one of the world well-known high-stakes tests, CET-4 （College English Test Band 4） changed from being generally accepted to being widely questioned in the past 25 years. In spite of a series of reforms of CET-4, the negative impact of CET-4 remains intense. Three main reasons are probed into here. Firstly, the objective of CET-4 is ambiguous. Secondly, the test objective does not accord with teaching objective. Finally, test contents do not match well with the practical language use. To improve the present passive state of CET-4, some suggestions are given.展开更多
A comparative study is conducted to compare the theory and application effect of two accident causation models, the human factors analysis and classification system（HFACS） and the accident causation ＂2-4＂ model（2...A comparative study is conducted to compare the theory and application effect of two accident causation models, the human factors analysis and classification system（HFACS） and the accident causation ＂2-4＂ model（24 Model）, as well as to provide a reference for safety researchers and accident investigators to select an appropriate accident analysis method. The two models are compared in terms of their theoretical foundations, cause classifications, accident analysis processes, application ranges, and accident prevention strategies. A coal and gas outburst accident is then analyzed using both models, and the application results are compared. This study shows that both the 24 Model and HFACS have strong theoretical foundations, and they can each be applied in various domains. In addition, the cause classification in HFACS is more practical, and its accident analysis process is more convenient. On the other hand, the 24 Model includes external factors, which makes the cause analysis more systematic and comprehensive. Moreover, the 24 Model puts forward more corresponding measures to prevent accidents.展开更多
Cancer is cell fleeing from death by blocking the intrinsic and extrinsic programs of cell death. The six elements that shut down those programs are: muc-1, muc-4, muc-16, Bcl-2, MMPs and decoy R3. The nuclear factor-...Cancer is cell fleeing from death by blocking the intrinsic and extrinsic programs of cell death. The six elements that shut down those programs are: muc-1, muc-4, muc-16, Bcl-2, MMPs and decoy R3. The nuclear factor-kappa B (NF-Kb) stimulates the expression of genes responsible for the production of those elements, which are used by cells to block those two programs. In other words, the nuclear factor kappa B (NF-KB) is responsible for blocking both programs. Therefore, the nuclear factor kappa B (NF-Kb) is the true cause of cancer.展开更多
<strong><em>Background: </em></strong>The appropriate time to initiate antiretroviral therapy (ART) in HIV/AIDS patients is determined by measurement of CD4+/CD8+ T cell count. The CD4/CD8+ T c...<strong><em>Background: </em></strong>The appropriate time to initiate antiretroviral therapy (ART) in HIV/AIDS patients is determined by measurement of CD4+/CD8+ T cell count. The CD4/CD8+ T cell count is also useful, together with viral load, in monitoring disease progression and effectiveness treatment regimens. Several factors may contribute to sample rejection during the CD4+/CD8+ T cells count, resulting in negative effects on patient management. <strong> <em>Objective: </em></strong>Evaluate the causes for CD4+CD8+ T cell count sample rejection at the Kenyatta National Hospital Comprehensive Care Center Laboratory. <strong><em>Method:</em></strong> A retrospective cross-sectional study was conducted between 2018 and 2020. Data was obtained from the “rejected samples” for Partec<sup>R</sup> FlowCyp flow cytometry file. Designed data collection sheet was used for data capture. A total of 3972 samples were submitted for CD4+/CD8+ T cell count during the study period. Causes for sample rejection were numbered 1 to 12, each representing a reason for sample rejection. Number 1 was sub-categorized into clotted, hemolyzed, short-draw and lipemic. Data was analyzed using excel, and presented using tables, graphs and pie charts. Approval to conduct the study was obtained from KNH/UoN ERC. <strong> <em>Results: </em></strong>In the study period, 81/3972 (2.0%) samples were rejected. Samples submitted more than 48 hours after collection were mostly rejected. Other factors included improper collection technique, delayed testing, patient identification error and incorrect use of vacutainer. A combination of clotted samples, specimen submission more than 48 hours caused the most frequent sample rejection, followed with combination of specimen submission more than 48 hours, delayed testing and delayed specimen processing. Together, clotted samples, incorrect vacutainer and poor specimen label caused the least sample rejection. <strong><em>Conclusion:</em></strong> Sample rejection rate for CD4/CD8+ T cell count was relatively low, and multiple factors contributed to rejection. However, improved quality assurance will enable more benefit to patients who seek this test in the laboratory.展开更多
文摘As one of the world well-known high-stakes tests, CET-4 （College English Test Band 4） changed from being generally accepted to being widely questioned in the past 25 years. In spite of a series of reforms of CET-4, the negative impact of CET-4 remains intense. Three main reasons are probed into here. Firstly, the objective of CET-4 is ambiguous. Secondly, the test objective does not accord with teaching objective. Finally, test contents do not match well with the practical language use. To improve the present passive state of CET-4, some suggestions are given.
基金support from the State Key Program of the National Natural Science Foundation of China (No. 51534008)
文摘A comparative study is conducted to compare the theory and application effect of two accident causation models, the human factors analysis and classification system（HFACS） and the accident causation ＂2-4＂ model（24 Model）, as well as to provide a reference for safety researchers and accident investigators to select an appropriate accident analysis method. The two models are compared in terms of their theoretical foundations, cause classifications, accident analysis processes, application ranges, and accident prevention strategies. A coal and gas outburst accident is then analyzed using both models, and the application results are compared. This study shows that both the 24 Model and HFACS have strong theoretical foundations, and they can each be applied in various domains. In addition, the cause classification in HFACS is more practical, and its accident analysis process is more convenient. On the other hand, the 24 Model includes external factors, which makes the cause analysis more systematic and comprehensive. Moreover, the 24 Model puts forward more corresponding measures to prevent accidents.
文摘Cancer is cell fleeing from death by blocking the intrinsic and extrinsic programs of cell death. The six elements that shut down those programs are: muc-1, muc-4, muc-16, Bcl-2, MMPs and decoy R3. The nuclear factor-kappa B (NF-Kb) stimulates the expression of genes responsible for the production of those elements, which are used by cells to block those two programs. In other words, the nuclear factor kappa B (NF-KB) is responsible for blocking both programs. Therefore, the nuclear factor kappa B (NF-Kb) is the true cause of cancer.
文摘<strong><em>Background: </em></strong>The appropriate time to initiate antiretroviral therapy (ART) in HIV/AIDS patients is determined by measurement of CD4+/CD8+ T cell count. The CD4/CD8+ T cell count is also useful, together with viral load, in monitoring disease progression and effectiveness treatment regimens. Several factors may contribute to sample rejection during the CD4+/CD8+ T cells count, resulting in negative effects on patient management. <strong> <em>Objective: </em></strong>Evaluate the causes for CD4+CD8+ T cell count sample rejection at the Kenyatta National Hospital Comprehensive Care Center Laboratory. <strong><em>Method:</em></strong> A retrospective cross-sectional study was conducted between 2018 and 2020. Data was obtained from the “rejected samples” for Partec<sup>R</sup> FlowCyp flow cytometry file. Designed data collection sheet was used for data capture. A total of 3972 samples were submitted for CD4+/CD8+ T cell count during the study period. Causes for sample rejection were numbered 1 to 12, each representing a reason for sample rejection. Number 1 was sub-categorized into clotted, hemolyzed, short-draw and lipemic. Data was analyzed using excel, and presented using tables, graphs and pie charts. Approval to conduct the study was obtained from KNH/UoN ERC. <strong> <em>Results: </em></strong>In the study period, 81/3972 (2.0%) samples were rejected. Samples submitted more than 48 hours after collection were mostly rejected. Other factors included improper collection technique, delayed testing, patient identification error and incorrect use of vacutainer. A combination of clotted samples, specimen submission more than 48 hours caused the most frequent sample rejection, followed with combination of specimen submission more than 48 hours, delayed testing and delayed specimen processing. Together, clotted samples, incorrect vacutainer and poor specimen label caused the least sample rejection. <strong><em>Conclusion:</em></strong> Sample rejection rate for CD4/CD8+ T cell count was relatively low, and multiple factors contributed to rejection. However, improved quality assurance will enable more benefit to patients who seek this test in the laboratory.
