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statistical Procedures for Estimating and Detecting Climate Changes

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Advances in Atmospheric sciences 2006年第1期23卷 61-68页

作者： s. s. P. sHEN Department of Mathematical and statistical sciences University of AlbertaEdmontonCanada

This paper provides a concise description of the philosophy, mathematics, and algorithms for estimating, detecting, and attributing climate changes. The estimation follows the spectral method by using empirical orthogonal functions, also called the method of reduced space optimal averaging. The detection follows the linear regression method, which can be found in most textbooks about multivariate statistical techniques. The detection algorithms are described by using the space-time approach to avoid the non-stationarity problem. The paper includes （1） the optimal averaging method for minimizing the uncertainties of the global change estimate, （2） the weighted least square detection of both single and multiple signals, （3） numerical examples, and （4） the limitations of the linear optimal averaging and detection methods.

关键词： Climate change detection optimal averaging optimal detection mean square error multivariate analysis linear regression inference

Development of anti-corrosive coating on AZ31 Mg alloy subjected to plasma electrolytic oxidation at sub-zero temperature

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Journal of Magnesium and Alloys 2022年第7期10卷 1915-1929页

作者： s.Fatimah M.P.Kamil D.I.Han W.Al-Zoubi Y.G.Ko Materials Electrochemistry Group School of Materials Science and EngineeringYeungnam UniversityGyeongsan 38541Republic of Korea

Plasma electrolytic oxidation(PEO)is a promising surface treatment to generate adherent and thick anti-corrosive coating on light-weight metals(Al,Mg,Ti,etc.)using an eco-friendly alkaline *** energy plasma,however,inevitably generates porous structures that limit their practical *** present study proposes a straight-forward simple method by utilizing sub-zero electrolyte(268 K)to alter the plasma characteristics during formation of the protective coating on AZ31 Mg alloy via PEO with a comparison to the electrolyte at room temperature(298 K).In refrigerated electrolyte,the formation of micro-defects is suppressed relatively at the expense of low coating growth,which is measured to be twice lower than that at 298 K due to the temperature-dependent soft plasma discharges contributing to the development of the present *** a consequence,corrosion resistance of the sample processed at 268 K is superior to that of 298K,implying that the effect of coating thickness is less dominant than that of *** phenomenon is interpreted in relation to the ionic movement and oxide solidification controlled by soft plasma discharges arising from the temperature gradient between electrolyte and surface of the substrate during PEO.

关键词： AZ31 Mg alloy Plasma electrolytic oxidation sub-zero electrolyte Anti-corrosive coating Corrosion

Particularities of Anemia in the Elderly: Experience in a Geriatrics Department in senegal

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Journal of biosciences and Medicines 2023年第8期11卷 71-81页

作者： Assane sall Massamba bâ Pascal Tienin babou Rokhaya Djajheté Dalahata bâ Mamadou Coumé Geriatrics Department Fann/Dakar University Hospital Dakar Senegal

background/Objective: Anemias are frequent conditions in geriatric practice. The etiologies are numerous, overlapping chronic and acute pathologies. it is also associated with high morbidity and mortality. In our context, few studies have addressed this issue, and none have been carried out in geriatric units with integrated geriatric dimensions. The aim of this study was to describe the particularities of anemia in old people in a geriatric short-stay service in senegal. Materials and methods: This was a retrospective, descriptive study from 01 May 2019 to 31 December 2021, involving people aged 60 or over, hospitalized in the geriatrics department of Fann Hospital (senegal) and presenting with anemia. Epidemiological, clinical and evolutionary characteristics were collected and analyzed using sPss 24.0 software. Results: The prevalence of anemia was 32.3%. The mean age of our sample was 78.7 ± 8.5 years. Arterial high blood pressure (59.3%), diabetes mellitus (22.8%), prostate disease (12.3%) were the most frequent comorbidities. Clinical manifestations were dominated by physical asthenia (80%) and severe alteration of general condition (72%). The geriatric syndromes were essentially represented by the loss of Activities Daily Living (ADL) autonomy (65%), undernutrition (59%) and frailty (46%). The mean hemoglobin level was 8.4 g/dl ± 2.1. The main etiologies were infections (32.7%), chronic kidney disease (20.9%), iron deficiency (7.4%). The mean hospital stay was 8 days ± 3.7 days and the mortality rate was 19%. Conclusion: Anemia is a frequent occurrence in geriatric medicine, with a high morbidity and mortality rate;its expression is often atypical, with frequent geriatric syndromes;the etiologies are multiple and often interrelated, requiring an exhaustive and multidimensional approach.

关键词： Anemia Geriatric senegal

Assessing Levels and Health Risks of Fluoride and Heavy Metal Contamination in Drinking Water

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Journal of Geoscience and Environment Protection 2022年第11期10卷 15-34页

作者： Ali sanou Namory Méité Amadou Kouyaté Elisephane Irankunda Alfred Niamien Kouamé Aka Eric Koffi Koffi Jean-Paul bohoussou Lébé Prisca M.-s. Kouakou Institut National Polytechnique Félix Houphouë t-boigny (INP-Hb) Laboratoire des Procédés Industriels de Synthèses de l’Environnement et des Energies Nouvelles (LAPISEN) Yamoussoukro C&#244 te d’Ivoire Institut National Polytechnique Félix Houphouë t-boigny (INP-Hb) Laboratoire de Thermodynamique Traitement et Sciences des Surfaces et Interfaces Ingénierie et Physicochimie des Procédés et de Mécanique des Matériaux (L2-TSIPM) Yamoussoukro C&#244 te d’Ivoire Ecole Normale supérieure (ENs) Laboratoire des Sciences Physiques Fondamentales et Appliquées (LSPFA) Abidjan C&#244 te d’Ivoire Université Félix Houphouë t-boigny (UFHb) UFR SSMT Laboratoire de Constitution et Réaction de la Matière (LCRM) Abidjan C&#244 te d’Ivoire Université Félix Houphouë t-boigny (UFHb) UFR SSMT Laboratoire de Constitution et Réaction de la Matière (LCRM) Abidjan C&#244te d’Ivoire Laboratoire des sciences et Technologies de l’Environnement UFR Environnement Université Jean Lorougnon Guédé Daloa C&#244 te d’Ivoire school of Computer science and Information Technology The East African University Kajiado Kenya

A systematic study was carried out to assess the level of contamination with fluorides and heavy metals in the drinking water of the city of Daloa as well as the risks to the health of consumers. The waters of 11.11% of the sites sampled exceeded the fluoride limit for drinking water with a contamination index (CI) greater than 0. All the waters recorded concentrations of cadmium (Cd), copper (Cu), iron (Fe), manganese (Mn) and lead (Pb) above the recommended values with CI > 0. However, 22.22% of the sites recorded concentrations below the standard for zinc (Zn) with IC ssessment of adverse effects on human health showed that the chronic daily intake (CDI) of fluorine and metals was less than 1 (CDI both adults and children except for Zn where the CDI > 1 for children in 22.22% of drinking water studied. HQs have an average of less than 1 for fluorine and greater than 1 for all metals. Moreover, the danger indices have values greater than 1. The incremental lifetime cancer risk (ILCR) and the total ILCR are above the recommended values. These results showed that the drinking water sampled is of poor quality due to higher levels of heavy metals, which can constitute a danger to human health. Long-term use of one of these poor quality waters can lead to cancer in consumers. It is therefore necessary to treat this water in order to eliminate the metals before using it for drinking. This study can help decision-makers and competent authorities in charge of water management.

关键词： Physico-Chemical Parameters Fluoride Heavy Metals Drinking Water sanitary Risks

A guide for selecting the appropriate plot design to measure ungulate browsing

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Forest Ecosystems 2023年第6期10卷 732-742页

作者： suzanne T.s.van beeck Calkoen Jerome Milch Andrea D.Kupferschmid Christian Fiderer Marco Heurich Department of Visitor Management and National Park Monitoring Bavarian Forest National ParkFreyunger Straße 294481 GrafenauGermany Wildlife Ecology and Management Albert-Ludwigs-University of FreiburgTennenbacher Str.479106 FreiburgGermany swiss Federal Research Institute WsL Zürcherstrasse 1118903 BirmensdorfSwitzerland Faculty of Applied Ecology Agricultural Sciences and BiotechnologyInstitute for Forest and Wildlife ManagementCampus EvenstadKoppangNorway

Ungulate browsing often impairs tree regeneration,thus preventing the achievement of economic or conservation *** ungulate management would thus benefit from a practical decision tool that facilitates method selection from a wide range of monitoring methods and indicators currently *** this study,we first provide an overview of the different browsing-impact monitoring methods and indicators currently *** then present a newly developed decision matrix for method evaluation that can assist forest stakeholders in choosing the browsing-impact monitoring method best suited to their needs,based on the selected *** first step involved two separate literature reviews to create an overview of the currently applied methods and to select the indicators best suited for measuring browsing *** types of indicator groups with their respective parameters were considered important for method evaluation:browsing indicators(*** density,browsing incidents),performance indicators(***,expertise)and data quality indicators(*** to measurement errors).subsequently,all parameters defined within each indicator group were categorised and a grade was assigned to each *** create the final method-indicator matrix,each browsing-impact monitoring method received a grade for each parameter within all indicator groups,reflecting the specific advantages and disadvantages of implementing the respective parameter within a specific *** utility of the matrix in selecting the most suitable monitoring method was then demonstrated using the example of Germany's national *** on the weights added to the method-indicator matrix,as defined by national park representatives,and considering local requirements the nearest-tree method was favoured over the other two *** newly developed matrix provides a more scientific objectification of ungulate browsing-impact measures and can be easily used by forest man

关键词： Ungulate browsing impact Monitoring Indicator Decision matrix Forest management

A study on Risk Factors for Venous Thromboembolism and the Requirement of Thromboprophylaxis in Pregnancy and Postpartum Period in a Tertiary Care Centre in south Asian Country: A Cross sectional study

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Open Journal of Obstetrics and Gynecology 2023年第3期13卷 403-413页

作者： P. L. A. sirisena s. N. samarakkody b. subhani D. Gunawardana M. A. K. Perera C. Rathnayake De soysa Hospital for Women Colombo Sri Lanka Colombo south Teaching Hospital Colombo Sri Lanka National Hospital of sri Lanka Colombo Sri Lanka Provincial Department of Health services Central Province Kandy Sri Lanka Department of Obstetrics and Gynaecology University of Peradeniya Kandy Sri Lanka

Introduction: Thrombosis is a major cause of maternal death worldwide. During pregnancy, the risk of venous thromboembolism (VTE) increases fourfold to five-fold and contributes towards maternal morbidity and mortality. sri Lanka does not have a proper assessment tool to detect and manage it in the antenatal care. Objectives: To identify risks factors for VTE among pregnant mothers, postpartum mothers according to RCOG (Royal College of Obstetricians) risk categorization and to assess the requirement of thromboprophylaxis. Method: A cross sectional study was conducted at the antenatal clinics and obstetrics and gynaecology wards (ward 2, 5, 8) of De soysa Hospital for Women in 2021. Obstetric thromboprophylaxis risk assessment tool recommended by the RCOG was used for the risk assessment of pregnant mothers during the antenatal and postpartum period. Results: In antenatal period, obesity (bMI > 35), age more than 35 years and parity more than 3 were the commonest risk factors. Out of 404 mothers, 67.33% did not have any risk factors. Among others, 18.56%, 0.40%, 2.72%, 0.99% had a score of 1, 2, 3 and 4 respectively. Patients with intermediate (0.99%) and high risk (2.72%) were commenced on thromboprophylaxis from 28 weeks. The low-risk category was not started on any treatment (28.96%, n = 97). Approximately 96% of mothers did not require any thromboprophylaxis during antenatal period. Another 404 postnatal mothers were recruited for the study group. Elective caesarean section and caesarean section during labour were the main risks identified other than pre-existing antenatal risks. 39.95 % of mothers did not have any risk factors and 37.22% of mothers had a score of 1. Conclusions: VTE risk assessment tool can be implemented at national level to detect patients at risk of VTE and improve maternal care.

关键词： Venous Thromboembolism Postpartum Thromboprophylaxis Cross-sectional study Maternal Morbidity and Mortality

La_(2-x)CexCu_(1-y)Zn_yO_4 perovskites for high temperature water-gas shift reaction

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Journal of Natural Gas Chemistry 2009年第2期18卷 131-138页

作者： s. s. Maluf E. M. Assaf Instituto de Química de so Carlos Universidade de So Paulo Av. Trabalhador Socarlense400 So Carlos SP 13560-970 Brazil

The performance of La2-xCexCu1-yZnyO4 perovskites as catalysts for the high temperature water-gas shift reaction （HT-WGsR） was investigated. The catalysts were characterized by EDs, XRD, bET surface area, TPR, and XANEs. The results showed that all the perovskites exhibited the La2CuO4 orthorhombic structure, so the Pechini method is suitable for the preparation of pure perovskite. However, the La1.90Ce0.10CuO4 perovskite alone, when calcined at 350/700℃, also showed a （La0.935Ce0.065）2CuO4 perovskite with tetragonal struc- ture, which produced a surface area higher than the other perovskites. The perovskites that exhibited the best catalytic performance were those calcined at 350/700℃ and, among these, La1.90Ce0.10CuO4 was outstanding, probably because of the high surface area associated with the presence of the （La0.935Ce0.065）2CuO4 perovskite with tetragonal structure and orthorhombic La2CuO4 phase.

关键词： perovskite shift reaction lanthanum copper cerium

Improvement of Plasma Performance with Lithium Wall Conditioning in Aditya Tokamak

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Plasma science and Technology 2013年第2期15卷 123-128页

作者： M. b. CHOWDHURI R. MANCHANDA J. GHOsH s. b. bHATT Ajai KUMAR b. K. DAs K. A. JADEJA P. A. RAIJADA Manoj KUMAR s. bANERJEE Nilam RAMAIYA Aniruddh MALI Ketan M. PATEL Vinay KUMAR P. VAsU R. bHATTACHARYAY R. L. TANNA Y. shankara JOIsA P. K. ATREY C. V. s. RAO D. Chenna REDDY P. K. CHATTOPADHYAY R. JHA Y. C. sAXENA Aditya team Institute for Plasma Research Bhat Gandhinagar 382 428 India

Lithiumization of the vacuum vessel wall of the Aditya tokamak using a lithium rod exposed to glow discharge cleaning plasma has been done to understand its effect on plasma performance. After the Li-coating, an increment of ~100 eV in plasma electron temperature has been observed in most of the discharges compared to discharges without Li coating, and the shot reproducibility is considerably improved. Detailed studies of impurity behaviour and hydrogen recycling are made in the Li coated discharges by observing spectral lines of hydrogen, carbon, and oxygen in the visible region using optical fiber, an interference filter, and PMT based systems. A large reduction in O I signal （up to ~40% to 50%） and a 20% to 30% decrease of Ha signal indicate significant reduction of wall recycling. Furthermore, VUV emissions from O V and Fe XV monitored by a grazing incidence monochromator also show the reduction. Lower Fe XV emission indicates the declined impurity penetration to the core plasma in the Li coated discharges. significant increase of the particle and energy confinement times and the reduction of Zeff of the plasma certainly indicate the improved plasma parameters in the Aditya tokamak after lithium wall conditioning.

关键词： lithiumization wall conditioning impurity Aditya tokamak

Topology Chemical Process Research on the Condensing and Growing Phase Multi Micro Oil Droplets based on Hydrodynamics

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Journal of beijing Institute of Technology 2009年第1期18卷 84-88页

作者：周毅李旋旗张东翔 TAPACOb b b Civil and Environment Engineering school University of Science and Technology Beijing Institute of New Economic Beijing Institute of Technology Institute of Urban Environment Chinese Academy of Sciences school of Chemical Engineering and Environment Beijing Institute of Technology D.I. Mendeleev University of Chemical Technology of Russia

The hydrodynamic research about the droplet condensing of the multi phase liquid state on the surface of the coal glass and water discusses the deepening process of convex shape curve and the formation of s shape, and puts emphasis on describing the diagram formation method of the later. In the induction period the active diagram of the micro droplet is decided by pH value forming as convex shape diagram or s shape diagram. When pH value is above 4.0, the damage of convex shape diagram cannot be recovered, in that case produce s shape activity diagram. When pH value is equal to or above 12.0, the hard surface with alkali liquid state loses adhesion, so that the micro droplet condensing of the multi phase liquid state stops completely. The research result shows that the water cleaning conditions of getting rid of the oil micro droplets can be decided by the pH value.

关键词： growing of micro oil droplet condensing of micro oil droplet topology chemical process convexshape diagram s shape diagram