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Chemical Research in Chinese Universities 1989年第4期5卷 357-362页

作者： He Binglin(Ho Ping-lum), Sun Juntan, Li Hong, Sang Junjie and Zhao Fenzhi (Institute of Polymer Chemistry, Nankai University, Tianjin)

Tetranuclear Rh-Co bimetallic cluster was synthesized and characterized by IR and XPS. The properties of the anchored catalysts, its stability and the ligand effect were also studied. The experimental results show that the optimal conditions for the hydroformylation of hexene-1 are as follows: the temperature is 80℃, reaction time 8 h, pressure 5. 88×105 Pa, and molar ratio of H2/CO 1. 2/1. 0. Functional groups attached to the donor atom(N) possess more or less some influence on the catalytic behavior. Compared with the homogeneous cluster, the polymer-supported bimetallic cluster is more stable. After the catalytic reaction, the structure of the anchored catalysts was not destroyed. X-ray photoelectron spectroscopy characterization indicates that there is a weak interaction between the polymer support and the active metals.

关键词： Rhodium-cobalt cluster Polymer-supported catalysts Hydroformylation

An Assessment of Predisposing Factors of Atherogenic Dyslipidemia in an Urban Pediatric Population in Cameroon

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Journal of Biosciences and Medicines 2022年第7期10卷 1-18页

作者： Lifoter Kenneth Navti Loveline lum Niba Choumessi Tchewonpi Aphrodite Mary Bih Atanga Department of Biochemistry The University of Bamenda Bambili Cameroon Nutrition and Health Research Group (NHRG) Bamenda Cameroon Department of Public Health The University of Bamenda Bambili Cameroon Department of Nursing and Midwifery The University of Bamenda Bambili Cameroon

Background: Dyslipidemia in childhood contributes to an increased risk of cardiovascular diseases later in life. This study sets out to determine the prevalence of dyslipidemia and describe the associations between selected variables and dyslipidemia in Cameroon urban children. Methods: This cross-sectional hospital-based study included 415 children (188 boys and 227 girls) between the ages of 5 and 16 years. Dyslipidemia was defined as an abnormal value of one or more of the following lipids: Total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C). Percentage body fat (%BF) was estimated using bio-electric impedance analysis. A structured questionnaire was used by parents to report physical activity, screen time and eating habits of the children. Relationships between predictors and dyslipidemia were assessed using multiple binary logistic regression analyses. Results: The prevalence of dyslipidemia was 46.0%. Dyslipidemic children had significantly higher %BF, TG and LDL-C and lower HDL-C than the normal children (p p = 0.004), short stature (OR 2.8, 95% CI 1.1 - 6.8, p = 0.041), physical activity p Conclusion: This study confirms that obesity, short stature, physical activity les were associated with dyslipidemia. Also, a high proportion of children had one or more lipid disorders. This is concerning and indicates the importance of assessing dyslipidemia in pre-school children in future studies.

关键词： Dyslipidemia Children Percentage Body Fat Stature Cameroon

MRI成像参数对腰椎间盘突出症患者经皮椎间孔镜术后疗效的预测价值

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中国当代医药 2024年第21期31卷 99-102页

作者：康乐廖文军欧阳斯娟廖文伟新余钢铁集团有限公司中心医院临床营养科江西新余338000 新余钢铁集团有限公司中心医院心内科江西新余338000 新余钢铁集团有限公司中心医院院办公室江西新余338000 新余钢铁股份有限公司数智化部IT系统开发室江西新余338000

目的探讨MRI成像参数对腰椎间盘突出症(LDH)患者经皮椎间孔镜(PTED)术后疗效的预测价值,以指导临床治疗措施的拟定,提高对LDH患者的治疗效果。方法回顾性收集2021年1月至2022年12月在新余钢铁集团有限公司中心医院经PTED术后疗效良好的4... 详细信息

目的探讨MRI成像参数对腰椎间盘突出症(LDH)患者经皮椎间孔镜(PTED)术后疗效的预测价值,以指导临床治疗措施的拟定,提高对LDH患者的治疗效果。方法回顾性收集2021年1月至2022年12月在新余钢铁集团有限公司中心医院经PTED术后疗效良好的40例LDH患者作为良好组,并收集同期经PTED术后疗效不佳的40例LDH患者作为不良组。所有患者资料均完整,统计两组患者的基线资料及MRI成像参数并进行比较,重点分析MRI成像参数预测LDH患者经PTED术后疗效的价值。结果不良组两侧腰大肌、多裂肌横截面面积差值均高于良好组,差异有统计学意义(P0.80,预测价值较为理想,且以联合预测价值最佳,联合预测的AUC=0.891,灵敏度为0.800,特异度为0.850。结论LDH患者PTED术前MRI成像参数中两侧腰大肌、多裂肌横截面面积差值过表达,可能提示术后疗效不佳。

关键词：腰椎间盘突出症经皮椎间孔镜术 MRI 疗效预测价值

Modified method of single cell analysis by Quadrupole ICP-MS

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Modified method of single cell analysis by Quadrupole ICP-MS

第五届全国原子光谱及相关技术学术会议

作者： Judy Tsz-Shan lum Kelvin Sze-Yin leung Department of Chemistry Hong Kong Baptist University Partner State Key Laboratory of Environmental and Biological Analysis Hong Kong Baptist University

Single cell-ICP-MS or single particle-ICP-MS is an emerging technique for the analysis of nanoparticles or cells.[1,2] It is well known that conventional ICP-MS with a quadrupole mass analyzer has limitation in such analysis,due to the one mass measurement at a *** contrasts with the simultaneous multi-elemental analysis performed by ICP-TOF-MS,in which a broad range of isotopes can be *** this project,a modified method of single cell analysis using ICP-QMS was *** masses were monitored（2-mass mode） during the analysis in comparison to that of single mass in the conventional approach in single particle-ICP-MS *** such as particle size,number of particles and the size distribution profile obtained by the two modes were *** proposed method was proved successful in mixtures of AgNP and AuNP with different particle *** sizes determined by the two analysis modes were in a good agreement with each *** percentage difference of the evaluated parameters of the two modes are within the acceptable range,demonstrating the potential of 2-mass mode in comparing two elements in cells or ***,the developed method was used in the analysis of single-cell algae treated with nanoparticles,to study the nanoparticle uptake of the cells after ***-TOFMS was also employed to supplement the information obtained by the *** the amount of information retrieved is not comparable to that by ICP-TOF-MS,the success of the current approach can extend the capability of ICP-QMS for multi-elemental detection in single cell level,offering useful information for single particle/cell analysis.

关键词： Single cell-ICP-MS nanoparticles inductively coupled plasma-quadrupole-mass spectrometry inductively coupled plasma time-of-flight mass spectrometry

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中国抗震设计之我见

建筑结构学报 1989年第5期10卷 77-80页

作者：林秉旋美国夏威夷林氏岩石工程顾问公司总裁

根据墨西哥地震(1985)资料,大多数建筑物的破坏是由柱的破坏造成的,而柱配筋占用了近整个建筑物钢筋用量的一半。本文提出在柱的设计中采用有如桩那样的一种新的设计思想,即柱中配筋采用预应力受拉钢筋和螺旋形箍筋;以及采用预制的预应... 详细信息

根据墨西哥地震(1985)资料,大多数建筑物的破坏是由柱的破坏造成的,而柱配筋占用了近整个建筑物钢筋用量的一半。本文提出在柱的设计中采用有如桩那样的一种新的设计思想,即柱中配筋采用预应力受拉钢筋和螺旋形箍筋;以及采用预制的预应力剪力墙墙板来抵抗侧移。这样也许能减轻震害,节约钢筋。

关键词：中国抗震设计建筑物螺旋形箍筋预应力剪力墙

A Pilot Study of Singapore＇s Young Chinese Parent＇sPerceptions, Attitude and Behaviours Towards Bilingual learning

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Sino-US English Teaching 2017年第9期14卷 523-538页

作者： Aw GuatPoh Connie lum PENG Xuan-hui CHEN Yuan TONG Qi-ying Nanyang Technological University Singapore Singapore

This study aims to study parents＇ attitude, perceptions, and behaviours towards bilingual education in Singapore＇sbilingual social context. The study involves 78 young Singapore＇s Chinese parents, using mixed methodologiesincluding multiple choice questionnaire, interview, checklist, and focus group discussion to collect data. Qualitativeand quantitative researches have shown four important findings. First, young parents acknowledge the importanceof learning mother tongue to maintain cultural heritage. They also realize that Chinese could become their nextgeneration＇s crucial social capital in the future. Those families have great potential in raising bilingual ***, more attention should be paid to the gap between young parents＇ positive attitude and passive behaviourin supporting children＇s bilingual learning. Third, there are some misunderstandings about bilingual learning.

关键词： Singapore, bilingual education, parents' attitude, parents' perceptions, parents' behaviours

The Contribution of Linear Growth Components to Hypertension in Secondary School Adolescents in an Urban Setting in Cameroon

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Journal of Biosciences and Medicines 2022年第12期10卷 151-166页

作者： Loveline lum Niba Lifoter Kenneth Navti Afahnwi Alvine Takem Mary Bi Suh Atanga Department of Public Health The University of Bamenda Bambili Cameroon Nutrition and Health Research Group (NHRG) Bamenda Cameroon Department of Biochemistry The University of Bamenda Bambili Cameroon Department of Nursing and Midwifery The University of Bamenda Bambili Cameroon

Background: Components of height have been found to be positively associated with blood pressure (BP) both in developed and developing nations. However, amongst Cameroon secondary school adolescents, the relationship between heights, SH and SH/H with BP has rarely been studied. The purpose of this study was to determine the proportion of secondary school adolescents with elevated BP and high BP and to evaluate the relationship between the different components of linear growth with BP. Methods: An institution-based cross-sectional study involving 602 adolescents (399 girls and 203 boys, mean age 14.9 ± 2.3 years) attending some public and private secondary schools in the Bamenda municipality of the North West Region of Cameroon. Anthropometric and BP measurements were carried out following standard procedures. Pearson correlation and linear regression were used to determine the relationship between the various components of height (height, SH, SH/H) with BP amongst the children. Results: The overall prevalence of elevated BP and hypertension amongst the study participants was 21.9% and 15.6% respectively (with 8.3% and 7.3% of the hypertensive children in Stage I and Stage II respectively). However, there were no significant gender differences in the prevalence of elevated BP and high BP (p = 0.497). Girls had a significantly (p Conclusion: This study has demonstrated that height was positively associated with SBP amongst children and adolescents. Thus, height can be used in predicting adolescents with a high risk of developing high BP in our setting.

关键词： Linear Growth Components Hypertension Secondary School Adolescents Cameroon

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空间智能及自主系统

控制工程（北京） 1990年第5期 33-42页

作者： lum,H 卢欣

Evaluation of Regeneration Stock Alternatives for Optimization of Growth and Survival of Field-Grown Forest Trees

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Journal of Life Sciences 2013年第5期7卷 507-516页

作者： Titus Fondo Ambebe lum.ayeoffe Fontem Balgah Roland Azibo Njoya Moses Tita Mogho Department of Botany and Plant Physiology Faculty of Science University ofBuea Buea Cameroon Faculty of Agriculture and Veterinary Medicine University of Buea Buea Cameroon Department of Biological Sciences Faculty of Science University ofBamenda Bamenda Cameroon

Successful reforestation depends on the use of stock material that has a high potential for growth and survival in the environment where it is out-planted. This study is aimed at raising awareness on plant traits that are useful in evaluating the reforestation potential of seedlings and cuttings. The authors reviewed relevant literature on the assessment of quality of seedlings and cuttings and on the comparison of field performance of the two stock types. Results indicated that root-collar diameter, shoot height, root mass, number of first-order lateral roots and shoot-root ratio are morphological parameters whereas root growth potential, water relations, photosynthetic capacity and dormancy status are physiological traits that could be used as a basis for rating and comparing the suitability of seedlings and cuttings for reforestation. There is a discrepancy among studies on the field performance of seedlings and cuttings. It is concluded that a combination of morphological and physiological parameters should be used in evaluating the relative value of cuttings and seedlings. In addition, the age of the parent plant of a cutting should be taken into consideration when comparing the reforestation potential of the two stock alternatives.

关键词： Cutting donor plant age reforestation seedling growth and survival.

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适用于汽车和电信的电源解决方案

今日电子 2017年第4期 27-30页

作者： Meilissa lum 凌力尔特公司

隔离二极管广泛地应用于电源以解决诸多的问题。在汽车系统中,当更换电池或车辆助推起动时,一个串联隔离二极管可提供针对意外电池反接的保护作用。高可用性系统和电信配电使用隔离二极管以通过电源的并联实现冗余。另外,二极管还用于... 详细信息

隔离二极管广泛地应用于电源以解决诸多的问题。在汽车系统中,当更换电池或车辆助推起动时,一个串联隔离二极管可提供针对意外电池反接的保护作用。高可用性系统和电信配电使用隔离二极管以通过电源的并联实现冗余。另外,二极管还用于防止储能电容器在需要进行某种短暂的输出电压保持以安然度过输入压降或噪声尖峰的场合中放电,或者在输入电源突发故障时使负载能够平稳地断电。

关键词：电源解决方案输入电源冗余电源储能电容器汽车系统肖特基二极管输出电压正向电流正向电压反向电流