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Influence of gaseous and particulate species on neutralization processes of polar aerosol and snow——A case study from Ny-?lesund

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Journal of Environmental Sciences 2019年第2期31卷 12-25页

作者： roseline C.Thakur Meloth Thamban ESSO-National Centre for Antarctic and Ocean Research Institute of Atmospheric and Earth System Research University of Helsinki

The inter-conversion of nitrogen and sulfur species between the gas and particulate phases and their interaction with alkaline species influences the acidity of the aerosols and surface snow. To better understand these processes, a short field campaign was undertaken in Ny-?lesund,Svalbard, during 13th April 2012 to 24th April 2012. Air measurements were carried out through a particulate sampler equipped with denuders and filter packs for simultaneous collection of trace gases(HNO_3, NO_2, SO_2 and reactive nitrogen compounds) and aerosols, with daily collection of snow samples. Ionic composition of the samples was analyzed using ion chromatography technique. The results suggested that nitrate-rich aerosols are formed when PAN(peroxy acetyl nitrate) disassociates to form NO_2 and HNO_3 which further hydrolyzes to form pNO_3^-(particulate nitrate). This resulted in a high contribution of pNO_3^-(62%) to the total nitrogen budget over the study area. The acidity of the aerosols and snow evaluated through cation/anion ratio(C/A)indicated alkaline conditions with C/A > 2. The bicarbonates/carbonates of Mg^(2+) played an important role in neutralization processes of surface snow while the role of NH_3 was dominant in aerosol neutralization processes. Such neutralization processes can increase the aerosol hygroscopicity causing warming. Chloride depletion in the snow was significant as compared to the aerosols, indicating two important processes, scavenging of coarse sea salt by the snow and gaseous adsorption of SO_2 on the snow surface. However, a more systematic and long term study is required for a better understanding of the neutralization processes and chemical interconversions.

关键词： Particulate Aerosol Scavenging Neutralization Arctic

Snowmelt Flood Mapping and Land Surface Short-Term Dynamics Assessment in a “Before-During-After” Scenario Based on Radar and Optical Satellite Imagery: Case Study Around the Lewisville Lake (Dallas/Fort Worth Metropolitan, Texas, USA)

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Advances in Remote Sensing 2023年第1期12卷 1-28页

作者： Alfred Homère Ngandam Mfondoum roseline Batcha Stats’NMaps Private Consulting Firm Dallas USA Department of Geography University of Yaoundé I Yaoundé Cameroon

The main goal of this study has been to map flood and assess land surface short-term dynamics in relation with snowy weather. The two recent snowfall events, which happened in, February 14th and 15th, of year 2021, and February 3rd and 4th, of year 2022, were chosen. A pre-analysis correlation was assumed between, the snow events, recurrency of floods, and changes in the land surface characteristics (i.e., wetness, energy, temperature), in a “Before-During-After” scenario. Active and passive microwave satellites data such as, Sentinel-1 synthetic aperture radar (SAR), Sentinel-2 multispectral instrument (MSI) and Landsat-9 Operation Land Imager-2/Thermal Infrared Sensors-2 (OLI-2/TIRS-2), as well as cloud databased global models for water and urban layers were used. The first step of processing was thresholding of SAR image, at 0.25 cutoff, based on bimodal histogram distribution, followed by the change analysis. The following processing consisted in the images transformation, by computing the tasseled cap transformation wetness (TCTw) and the surface albedo on MSI image. In addition, the land surface temperature (LST) was modeled from OLI-2/TIRS-2 image. Then, a 5th order polynomial regression was computed, between TCTw as dependent variable and, albedo and LST as independent variables. As a first result, an area of 5.6 km2 has been mapped as recurrently flooded from the two years assessment. The other output highlighted a constant increase of wetness (TCTw), considered most influential on land surface dynamics, comparatively to energy exchange (albedo) and temperature (LST). The “After” event dependency between the three indicators was highest, with a correlation coefficient, R2 = 0.682, confirming the persistence of wetness after-snowmelt. Validation over topographic layers confirmed that, recurrently flooded areas are mostly distributed on, lowest valley depth points, farthest distances

关键词： Snowmelt Flood Short-Term Dynamics Radar Optical Lewisville Lake

Do migrant remittances matter for financial development in Kenya?

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Financial Innovation 2019年第1期5卷 541-565页

作者： roseline Nyakerario Misati Anne Kamau Hared Nassir Research Department Central Bank of KenyaNairobi 60000-00200Kenya African Institute for Remittances Nairobi 52448-00200Kenya

The paper analyzes the relationship between remittances and financial development using Kenyan quarterly data from 2006 to *** different indicators of financial development are used:credit to the private sector as a share of GDP,the number of mobile transactions,the value of these mobile transactions,the number of mobile agents,and the number of bank *** results from using an autoregressive distributed lag demonstrate a strong,positive relationship between remittances and financial development in long-run *** suggests that higher levels of remittances provide opportunities for recipients to open bank accounts,enhance their savings,and access financial systems,in addition to exposing the previously unbanked to both new and existing financial *** results also confirm the potential advantage of embracing modern and advanced technology to facilitate international mobile *** international remittance transfers through mobile technology reduces costs by eliminating the need for physical branches and personnel to attend to walk-in *** from offering convenience and safety for remittance actors,this method also dominates traditional remittance business ***,a policy window exists for the government to leverage on remittances as a tool of financial inclusion and depth,and particularly through the continued expansion of regulatory space to accommodate the wider use of international mobile remittance transfer ***,given the strong,positive relationship between remittances and credit to the private sector as indicated by its share of GDP and number of bank accounts,commercial banks and other players in the remittance market may also find it useful to develop customized products for migrants to access their *** example,financial intermediaries can consider providing better deposit interest rates for diaspora deposits compared to deposits made in the local ***,these institut

关键词： Remittances Financial inclusion Technology

Evolving willingness and ability interfaces: An innovation led transformation journey

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International Journal of Innovation Studies 2020年第3期4卷 69-75页

作者： Douglas Grant Pushkar P.Jha roseline Wanjiru Ajay Bhalla HMRC Newcastle Upon TyneNE981ZZUK Newcastle Business School Northumbria UniversityNewcastle Upon TyneNE18STUK Cass Business School City UniversityLondonEC1Y 8TZUK

This paper discusses evolving willingness and ability during transformation initiatives in public sector organisations,a novel perspective contributing to addressing the need for better assessment and improved practice in managing transformation *** are formed by synthesising research,providing brief scenarios,and then through a summary narrative of transformation at a public sector organisation labelled PSO.A variation in willingness and ability levels and a divergence in these two variables across stakeholders comes across as an undercurrent to negotiate when the transformation is *** it manifests is captured in propositions,providing a view of key interactions and consequences.

关键词： Willingness Ability Performance Mediation

Iron Status of a People Living with HIV in Sub-Saharan Africa Using a Multi-Criteria Approach Based on the Determination of Blood Ferritin, sTfR, CRP and sTfR-F Index

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Journal of Biosciences and Medicines 2023年第5期11卷 239-246页

作者： Joelle Akissi Koffi Hugues Thierno Ahiboh Philémond By Delphine Gabillard Affi roseline Francisk Kouakou Inwoley Andre Centre de Diagnostic et de Recherche sur le SIDA et Autres Maladies Infectieuses CHU de Treichville Abidjan C&ocircte d’Ivoire Département de Biochimie et Biologie Moléculaire UFR Sciences Pharmaceutiques et Biologiques Université Félix Houphouet Boigny C&ocircte d’Ivoire Laboratoire de Biochimie Pharmacodynamie UFR Bosciences Université Félix Houphouet Boigny C&ocircte d’Ivoire Programme PAC-CI site ANRS DE Cô te d’Ivoire Abidjan C&ocircte d’Ivoire University of Bordeaux National Institute for Health and Medical Research (INSERM) UMR 1219 Research Institute for Sustainable Development (IRD) EMR 271 Bordeaux Population Health Centre Bordeaux France

Background: The assessment of iron status using a single biomarker of iron metabolism is not enough sensitive and specific to reliably diagnose iron deficiency associated with multiple comorbidities. The objective of this study was to describe the iron status of people living with HIV in sub-Saharan Africa using a multi-criteria approach based on the determination of blood ferritin, sTfR, CRP and the calculation of sTfR-F index. Methods: This study was conducted using a retrospective panel of 933 sera/plasmas. We determined serum ferritin concentration, serum sTfR concentration, and C-reactive protein (CRP) by immunoturbidimetry for each subject. The sTfR-F index was determined by calculating the sTfR/log ferritin ratio. The statistical test used was Chi2. Results: Regardless of the inflammatory syndrome, we determined 3.80%, 30.29%, and 42.70% iron deficiency based on the separate interpretation of ferritin concentration, sTfR, and sTfR-F calculation, respectively. We used those biomarkers in addition to CRP in an algorithm for the diagnosis of iron deficiency. Subjects without inflammatory syndrome, had iron deficiency of 2.89% (n = 26). Taking into account the presence of an inflammatory syndrome, the frequency obtained was n = 88 (9.78%). Overall, iron deficiency was diagnosed in 114 (12.67%) patients when we used the diagnostic algorithm. Conclusion: The use of diagnostic algorithms combining several biomarkers of iron metabolism and taking into account the presence or absence of an inflammatory syndrome is a good approach to detect a large number of iron deficiencies in a population. Therefore, an assessment of the effectiveness of different diagnostic algorithms is necessary.

关键词： Iron Deficiency Iron Metabolism Biomarkers HIV Infection CRP

Does Haptoglobin Phenotype Impact Infection Mortality?

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Advances in Biological Chemistry 2022年第5期12卷 143-150页

作者： Akissi Joelle Koffi Hugues Thierno Ahiboh Philémond By Delphine Gabillard roseline Affi Francisk Kouakou André Inwoley Département de Biochimie et Biologie Moléculaire UFR SPB Université Félix Houphouet Boigny Ivory Coast

Introduction: The physiological status of a subject and the pathophysiology in some diseases might be under the influence of haptoglobin phenotype. The objective of this work was to determine the relationship between mortality from HIV/AIDS infection and haptoglobin phenotype in a black population in Côte d’Ivoire. Methods: The study was conducted from a retrospective panel of 933 sera/plasma from the previous workup of the ANRS 12136 TEMPRANO trial at month 0 of patients in deferred-ART arms. For each subject, we determined the serum haptoglobin concentration, haptoglobin phenotype, and other variables from patient files from the TEMPRANO trial database. Statistical tests used were Chi-2, Fischer, and Kruskal-Wallis tests for non-gaussian distribution. We used the Kaplan-Meier method for survival analysis. Results: The distributions of the haptoglobin phenotypes were 32.3% for Hp 1-1, 39.5% for Hp 2-1 and 27.2% for Hp 2-2. The blood haptoglobin concentration seemed to be associated with haptoglobin phenotypes (p-value > 5%). The survival rate at M30 and for an extended follow-up up to 6 years was independent of haptoglobin phenotype (p-value > 5%). Besides, the haptoglobin phenotypes do not appear to be associated with CD4+ T-cell count and with hemoglobin concentration. Conclusion: Haptoglobin phenotype seems to not impact the mortality of HIV/AIDS infection. However, given the antioxidant and immunomodulatory properties of some haptoglobin phenotypes, it would be relevant to seek out possible confounding factors indirectly associated with haptoglobin phenotypes and clinical or biological infection variables.

关键词： HIV/AIDS Infection Phenotype of Haptoglobin CD4+ Cell Counts Hemoglobin Mortality

席夫碱作为缓蚀剂对盐酸溶液中AZ31镁合金的影响(英文)

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Transactions of Nonferrous Metals Society of China 2014年第6期24卷 1969-1977页

作者： S.THIRUGNANASELVI S.KUTTIRANI Amali roseline EMELDA Department of Chemistry Sri Ramanujar Engineering College Department of Chemistry BS Abdur Rahman University

在微波条件下,通过高纯度1-氨基-2萘酚4-磺酸与肉桂醛的缩合反应制备席夫碱(4Z)-4-(3-苯基烯丙叉氨基)-3-羟基萘-1-磺酸(AC)。采用红外光谱对制备的席夫碱进行分析。研究席夫碱作为缓蚀剂对AZ31镁合金在0.05mol/L盐酸中的缓蚀作用。通... 详细信息

在微波条件下,通过高纯度1-氨基-2萘酚4-磺酸与肉桂醛的缩合反应制备席夫碱(4Z)-4-(3-苯基烯丙叉氨基)-3-羟基萘-1-磺酸(AC)。采用红外光谱对制备的席夫碱进行分析。研究席夫碱作为缓蚀剂对AZ31镁合金在0.05mol/L盐酸中的缓蚀作用。通过质量损失法、动电位极化法和电化学交流阻抗谱(EIS)研究席夫碱化合物在AZ31镁合金腐蚀过程中的抑制作用。动电位极化曲线表明:席夫碱在所有浓度下能抑制阳极和阴极反应,是一种混合型缓蚀剂。EIS结果表明:随着添加剂浓度的增加,极化电阻增加而双电层电容减少。在0.05 mol/L盐酸中,席夫碱AC对AZ31镁合金表面的吸附符合Langmuir吸附等温式。

关键词：席夫碱 AZ31镁合金缓蚀剂动电位极化电化学交流阻抗谱

Detection, Biochemical and Molecular Characterization of Clostridium sporogens in Nono: A Nigerian Traditionally Fermented Yoghurt Drink

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Open Journal of Medical Microbiology 2023年第1期13卷 91-100页

作者： Nofisat Olaide Oyedokun Gbadebo Barnabas Olukotun Uchenna Iman Igwegbe Binta Buba Adamu roseline Rumi Ideh Olaitan Comfort Shekoni Amin Oderaa Igwegbe Department of Food and Industrial Biotechnology National Biotechnology Development Agency Musa Yar’adua Express Way Abuja Nigeria Department of Medical Microbiology University of Maiduguri Teaching Hospital (UMTH) Maiduguri Nigeria Department of Veterinary Medicine College of Food Agricultural and Environmental Science (CFAES) The Ohio State University Colombos USA Department of Food Science and Technology University of Maiduguri Maiduguri Nigeria

Nono is a traditionally fermented milk drink commonly consumed in the Northern parts of Nigeria. It is produced through the spontaneous fermentation of raw cow milk by Lactic Acid Bacteria (LAB), a process that could result to the contamination of the product with such pathogenic organisms as Clostridia spp. The aim of this research was therefore to determine the incidence of Clostridia species in thirty-two (32) ready-to-drink nono samples collected directly from a number of Fulani vendors in randomly selected locations within the Federal Capital Territory (FCT), Abuja, Nigeria. Isolated organisms were further subjected to some morphological and biochemical characterizations using standard microbiological procedures. The results obtained indicate that fourteen (14) isolates were putatively identified to be Clostridium sp., out of which five (5) isolates were confirmed to be Clostridium sporogens by a BLAST analysis of their respective 16SrRNA nucleotide sequence. It was concluded that, the detection of these pathogenic strains in frequently consumed product like nono could pose a public health risk and proactive measures to prevent an outbreak of food borne illness from nono consumption, were recommended.

关键词： Fermentation Nono Clostridium sporogens Pathogenic Food Borne Illness

Assessment of Heavy Metals and Radionuclide Concentrations in Mafikeng Waste Water Treatment Plant

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Journal of Water Resource and Protection 2016年第1期8卷 93-99页

作者： Manny Mathuthu roseline Olobatoke Centre for Applied Radiation Science and Technology North-West University Mafikeng Campus Mmabatho South Africa

A study was carried out to assess the heavy metal and radionuclide concentrations of water from the waste water treatment plant in Mafikeng Local Municipality. Ten water samples were collected from various stages of water treatment (n = 2 per stage) which included sewage delivered to the plant, the two treatment stages, the effluent and the community water. Samples were analyzed for heavy metal content using Inductive Coupled Plasma Mass Spectrometer. Gross α/β activity concentrations in water samples were evaluated by Liquid Scintillation Counting whereas the concentration of individual radionuclides was measured by gamma spectroscopy. The results showed marked reduction in the levels of heavy metal concentration from 3 μg/L (As) - 670 μg/L (Na) in sewage into the plant to 2 μg/L (As) - 170 μg/L (Fe) in the effluent. The gross α activity in all the water samples (7.7 - 8.02 Bq/L) exceeded the 0.1 Bq/L limit set by World Health Organization (WHO). Gamma spectroscopy revealed very high concentrations of 235U and 226Ra in water samples, with the lowest concentrations (9.35 and 5.44 Bq/L, respectively) in the in-coming sewage and highest concentrations (73.8 and 47 Bq/L, respectively) in the community water. All the values were considerably higher than the limits of South Africa Target Water Quality Range and WHO. However, the estimated total doses of the two radionuclides for the analyzed water samples (10.62 - 45.40 μSv·yr-1) were all well below the reference level of the committed effective dose of 100 μSv·yr-1 recommended by WHO.

关键词： Heavy Metals Radionuclides 235U 226Ra Water