This study was focused to assess major and trace elements in bauxitic duricrusts from Ngaoundal and its surroundings in order to establish their mining interest. To this end, fieldworks, mineralogical and geochemical ...This study was focused to assess major and trace elements in bauxitic duricrusts from Ngaoundal and its surroundings in order to establish their mining interest. To this end, fieldworks, mineralogical and geochemical analyses were carried out. Four facies of duricrust were identified and characterized from the summit to the top of the slope of the Ngaoundal mountain: scoriaceous, pisolitic, nodular and massive. Mineralogical and geochemical analyses performed on 16 samples, revealed a significant concentration of Al<sub>2</sub>O<sub>3</sub> mainly in the scoriaceous facies (over 45% in grade), moderate in Fe<sub>2</sub>O<sub>3</sub> (averaging 23.69%) and SiO<sub>2</sub> (averaging 21.7%). Trace elements were generally low, excluding Cr (421 ppm on average), Zr (327 ppm on average and V (213 ppm on average). In addition, the limited quantities of alkalis (Na<sub>2</sub>O, K<sub>2</sub>O) and alkaline earths metals (MgO, CaO) coupled with the very high values of Chemical Index of Alteration (CIA) and Mineralogical Index of Alteration (MIA), (more than 99%) attest to the intense weathering of the studied materials. Allitization and monosiallitization constituted the crystallochemical phenomena that have led to the development of bauxitic minerals. More than 90% of gibbsite in scoriaceous facies, 52.21% - 76.01% of kaolinite in pisolitic facies and more than 40% of hematite in nodular facies were quantified. The relationships between the constitutive components indicated their interdependency during the bauxitization phenomenon. The mineralogical and geochemical properties highlighted the mining interest of the studied duricrusts to be valorized.展开更多
Objective: The Surgical Apgar Score (SAS) is a tool for intraoperative stratification of the risk of serious complications in the early postoperative period. It varies from 0 to 10 points divided into three risk categ...Objective: The Surgical Apgar Score (SAS) is a tool for intraoperative stratification of the risk of serious complications in the early postoperative period. It varies from 0 to 10 points divided into three risk categories (0 to 4 high, 5 to 7 moderate, 8 to 10 low). The aim of the study was to evaluate its relevance in predicting the appearance of these complications. Material and methods: This descriptive and analytical study was carried out at the “Laquintinie” Hospital in Douala and at the Central Hospital in Yaounde, Cameroon. The main data were collected on a population of patients over 18 years old and recorded on a survey form. They consisted of variables of main interest and exposure variables. Univariate and multivariate statistical analysis using top-down logistic regression models made it possible to evaluate the association of each variable of main interest and each exposure variable. The association was significant at P Results: Of the 88 patients studied, the SAS was 3 hours. In multivariate, this link persisted only and strongly for the SAS OR (IC) 0.1 (0.1 - 0.2) and p = 000. Conclusion: The study found a specific and powerful link between the SAS score < 4 and the occurrence of complications in the early postoperative period, in favor of its relevance in predicting them.展开更多
采用PHA体内注射肾细胞直接制片法及银染法研究真鲷和黑鲷的核型及Ag—NOR带。指出这两种鱼的核型公式分别为2n=48,2st+46t,NF=48和2n=48,4m+4sm+2st+38t,NF=56。两种鱼的核型中各自唯一的一对亚端部着丝点染色体(st染色体)为典型的具...采用PHA体内注射肾细胞直接制片法及银染法研究真鲷和黑鲷的核型及Ag—NOR带。指出这两种鱼的核型公式分别为2n=48,2st+46t,NF=48和2n=48,4m+4sm+2st+38t,NF=56。两种鱼的核型中各自唯一的一对亚端部着丝点染色体(st染色体)为典型的具次缢痕的染色体。银染结果显示该次缢痕部位即为银染核仁组织者区域(Ag—Nucleolusorganizer regions NORs),并表现出多态性。同时,在这两种鱼的中期分裂相中普遍观察到了NORs联合现象。此外,还讨论了这两种鱼的亲缘关系和鲷科鱼类中两个类群及其核型的分化问题,认为从细胞遗传学角度看,鲷科鱼类的两个类群在演化过程中是分支进化的。展开更多
Based on the construction of urban landscape forest and application of stereoscopic landscapes in CAST(Chongqing Academy of Science and Technology),Ginkgo biloba L.,Ficus virens Ait.var.sublanceolata(Miq.) Corner,Cinn...Based on the construction of urban landscape forest and application of stereoscopic landscapes in CAST(Chongqing Academy of Science and Technology),Ginkgo biloba L.,Ficus virens Ait.var.sublanceolata(Miq.) Corner,Cinnamomum camphora and Magnolia liliflora were selected as major tree species and stereoscopic landscaping plants for the "CAST Stereoscopic Landscape Demonstration Project".Through investigating landscapes and functions of all these species in the urban landscaping,the authors anaiyzed stereoscopic plant landscapes of the CAST project,summarized application of these tree species in the stereoscopic landscapes,and concluded representativeness of these species in the CAST project.Finally,deficiencies of tree species in the CAST project,their maintenance and management were analyzed to ensure the reasonable application of tree species,and to provide references for the construction of urban landscape forest and popularization of stereoscopic landscapes.展开更多
文摘This study was focused to assess major and trace elements in bauxitic duricrusts from Ngaoundal and its surroundings in order to establish their mining interest. To this end, fieldworks, mineralogical and geochemical analyses were carried out. Four facies of duricrust were identified and characterized from the summit to the top of the slope of the Ngaoundal mountain: scoriaceous, pisolitic, nodular and massive. Mineralogical and geochemical analyses performed on 16 samples, revealed a significant concentration of Al<sub>2</sub>O<sub>3</sub> mainly in the scoriaceous facies (over 45% in grade), moderate in Fe<sub>2</sub>O<sub>3</sub> (averaging 23.69%) and SiO<sub>2</sub> (averaging 21.7%). Trace elements were generally low, excluding Cr (421 ppm on average), Zr (327 ppm on average and V (213 ppm on average). In addition, the limited quantities of alkalis (Na<sub>2</sub>O, K<sub>2</sub>O) and alkaline earths metals (MgO, CaO) coupled with the very high values of Chemical Index of Alteration (CIA) and Mineralogical Index of Alteration (MIA), (more than 99%) attest to the intense weathering of the studied materials. Allitization and monosiallitization constituted the crystallochemical phenomena that have led to the development of bauxitic minerals. More than 90% of gibbsite in scoriaceous facies, 52.21% - 76.01% of kaolinite in pisolitic facies and more than 40% of hematite in nodular facies were quantified. The relationships between the constitutive components indicated their interdependency during the bauxitization phenomenon. The mineralogical and geochemical properties highlighted the mining interest of the studied duricrusts to be valorized.
文摘Objective: The Surgical Apgar Score (SAS) is a tool for intraoperative stratification of the risk of serious complications in the early postoperative period. It varies from 0 to 10 points divided into three risk categories (0 to 4 high, 5 to 7 moderate, 8 to 10 low). The aim of the study was to evaluate its relevance in predicting the appearance of these complications. Material and methods: This descriptive and analytical study was carried out at the “Laquintinie” Hospital in Douala and at the Central Hospital in Yaounde, Cameroon. The main data were collected on a population of patients over 18 years old and recorded on a survey form. They consisted of variables of main interest and exposure variables. Univariate and multivariate statistical analysis using top-down logistic regression models made it possible to evaluate the association of each variable of main interest and each exposure variable. The association was significant at P Results: Of the 88 patients studied, the SAS was 3 hours. In multivariate, this link persisted only and strongly for the SAS OR (IC) 0.1 (0.1 - 0.2) and p = 000. Conclusion: The study found a specific and powerful link between the SAS score < 4 and the occurrence of complications in the early postoperative period, in favor of its relevance in predicting them.
文摘采用PHA体内注射肾细胞直接制片法及银染法研究真鲷和黑鲷的核型及Ag—NOR带。指出这两种鱼的核型公式分别为2n=48,2st+46t,NF=48和2n=48,4m+4sm+2st+38t,NF=56。两种鱼的核型中各自唯一的一对亚端部着丝点染色体(st染色体)为典型的具次缢痕的染色体。银染结果显示该次缢痕部位即为银染核仁组织者区域(Ag—Nucleolusorganizer regions NORs),并表现出多态性。同时,在这两种鱼的中期分裂相中普遍观察到了NORs联合现象。此外,还讨论了这两种鱼的亲缘关系和鲷科鱼类中两个类群及其核型的分化问题,认为从细胞遗传学角度看,鲷科鱼类的两个类群在演化过程中是分支进化的。
基金Supported by Key Scientific and Technological Program of Chongqing City(CSTC2010AB1105)~~
文摘Based on the construction of urban landscape forest and application of stereoscopic landscapes in CAST(Chongqing Academy of Science and Technology),Ginkgo biloba L.,Ficus virens Ait.var.sublanceolata(Miq.) Corner,Cinnamomum camphora and Magnolia liliflora were selected as major tree species and stereoscopic landscaping plants for the "CAST Stereoscopic Landscape Demonstration Project".Through investigating landscapes and functions of all these species in the urban landscaping,the authors anaiyzed stereoscopic plant landscapes of the CAST project,summarized application of these tree species in the stereoscopic landscapes,and concluded representativeness of these species in the CAST project.Finally,deficiencies of tree species in the CAST project,their maintenance and management were analyzed to ensure the reasonable application of tree species,and to provide references for the construction of urban landscape forest and popularization of stereoscopic landscapes.
