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The Potential of Quartzitic Veins in SW Cameroon for High-Purity Quartz

International Journal of Geosciences 2022年第4期13卷 281-302页

作者： Ngambu Aloysius Afahnwie arnold chi kedia Cheo Emmanuel Suh Cyrille Sigue Elisha Mutum Shemang Department of Geology Mining and Environmental Science Faculty of Science University of Bamenda Bamenda Cameroon Economic Geology Unit Department of Geology University of Buea Buea Cameroon Department of Earth and Environmental Sciences Botswana International University of Science and Technology Palapye Botswana

High-purity quartz (HPQ), the prime source of silica, is increasingly considered a strategic mineral in the world market because it is the raw material for special applications in high-tech industries owing to its unique physical and chemical properties. The expected growth in demand for HPQ implies that more sources have to be found. This is the primary motivation for this study which targets the Supe area, SW Region of Cameroon. The structural occurrences of quartz veins were mapped and samples collected. The chemical nature and textural features of these samples were subsequently analyzed by X-ray tomography, scanning electron microscopy (SEM), and electron microprobe analysis (EMPA). Three deformation events, D1 - D3 are recorded. D1 is marked by the development of the strong S1 foliation defined by the gneissic layering and schistosity. D2 is a NE-SW ductile to brittle sinistral shear that controlled the formation of tension gashes that served as subsequent pathways for quartz-rich hydrothermal fluids to circulate and eventually precipitate quartz. The presence of rutile, tourmaline, and mica inclusions in the Supe veins affects the purity of the quartz. However, quartz can be treated to improve its quality. Taking into consideration the nine determinant trace elements used to classify HPQ, three (Li, P, and B) are below detection limits, Al concentrations are within the HPQ, quartz market standard, and average natural abundance;Ti values are high above all three standards in all except one sample, while Na, Ca, K, and Fe values fluctuate, thus classifying one of the samples as high purity quartz and the others as low purity quartz. These veins define tension gashes which usually occur in an echelon arrangement covering a large surface area, suggesting that more of such veins probably exist in the Supe area. Consequently, the quality and potential quantity of HPQ veins in this area suggest a high potential

关键词： Quartz Veins High Purity Quartz X-Ray Tomography Rutile Tourmaline

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An Assessment and Geostatistics of Land-Use and Selected Physico-Chemical Properties of Soils in the Mount Cameroon Area

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Journal of Geographic Information System 2023年第2期15卷 244-266页

作者： Nchia Peter Ghong Ngwa Martin Ngwabie Godswill Azinwie Asongwe arnold chi kedia Cheo Emmanuel Suh Department of Agriculture and Environmental Engineering College of Technology University of Bamenda Bambili North West Region Cameroon Department of Environmental Science University of Buea Buea South West Region Cameroon School of Geographical Sciences and Urban Planning Arizona State University Tempe AZ USA Department of Geology Faculty of Science University of Bamenda Bambili North West Region Cameroon Economic Geology Unit Department of Geology University of Buea Buea South West Region Cameroon

This work investigated the land-use/land-cover and some physico-chemical properties of the soils of Mt Cameroon and presented same in maps. ArcGIS Pro mapping software, Landsat images, Global Positioning Systems (GPS) coordinates collected from the field combined with updated shape files from competent services were used to produce the location and land-use/land-cover maps. Sixteen topsoil samples (0 - 20 cm) were collected, 4 from each land use/cover category: farmland, forest, plantation and settlement, and analysed for soil pH, cation exchange capacity (CEC), bulk density, moisture content and soil texture, in the laboratory using standard analytical procedures. This data was used to produce spatial distribution maps using ordinary kriging, in ArcGIS Pro. The main terrestrial land use/cover categories comprised of the forest (mangrove, lowland, montane and sub-montane), agroforestry, plantations, grassland, settlement, cropland, shrubby savannah, and bare lava. Bulk density showed the highest values in settlement areas and least values under forest land-use categories. Soil moisture content exhibited a reverse trend compared to that of soil bulk density. Forest soils were the sandiest while soils in plantation agricultural land were the most clayey. The soils were slightly acidic to neutral with soils from agricultural land being more acidic (pH(water) = 5.43). It is discernible from the results that the conversion from forest to other land use/cover classes enhances soil degradation and that soil physico-chemical properties adequately serve as indicators of soil quality in the Mt Cameroon area.

关键词： Geographic Information Systems Geostatistics Land-Use Mt Cameroon Soil Quality Thematic Maps

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Magnetic-Field Effects on Donor Impurity States in a Quantum Well

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World Journal of Condensed Matter Physics 2012年第4期2卷 188-191页

作者： arnold Abramov Kuang-chi Institute of Advanced Technology Shenzhen China Department of Applied Mathematics Donbass State Engineering Academy Kramatorsk Ukraine

Green’s function technique is used to obtain the solution of Shredinger equation for impurity states in a quantum well (QW) under the magnetic field. Binding energy of impurity states is defined as poles of the wave function. We studied effects of the magnetic field magnitude and impurity position on the binding energy. The calculations were performed for both ground and excited states. The dependences of binding energies versus impurity position and magnetic field are presented for GaAs/Al0.3Ga0.7As QW.

关键词： Quantum Well Impurity Binding Energy Magnetic Field

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Propagation of Electromagnetic Wave through Anisotropic Graded Refractive Index Profile

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Journal of Applied Mathematics and Physics 2014年第1期2卷 47-50页

作者： arnold Abramov Lin Luan Kuang-chi Institute of Advanced Technology Shenzhen China

Propagation of electromagnetic wave (EW) through multilayer structure consisting anisotropic layers with gradient refractive index material is studied theoretically. Analytical solution for linear dependence of refractive index profile is examined. The structure consist the forbidden gaps, which are sensitive to parameters of refractive index profile.

关键词： Electromagnetic Refractive Index Gradient Layer

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Platelets Levels before and after Surgical Intervention in Patients with Oral and Maxillofacial Tumors at MNH, Tanzania

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Surgical Science 2015年第1期6卷 7-11页

作者： Jeremiah Moshy Karpal Singh Sohal Sira Stanslaus Owibingire arnold Augustino Department of Oral and Maxillofacial Surgery MUHAS Dar es Salaam Tanzania Department of Oral and Maxillofacial Surgery MNH Dar es Salaam Tanzania

Background: There are documented effects of platelets on the solid tumors which need further study. The elevated platelet counts have been described for majority of cancers. There is inadequate information of effect of benign and malignant oral and maxillofacial tumors on the regulation of platelets. The aim of this study was to investigate the changes in platelet counts among patients with oral and maxillofacial benign and malignant tumors following surgical interventions. Methods: A descriptive postoperative study was done whereby patients with benign and malignant oral and maxillofacial tumors who met the inclusion criteria were included. The included patients were those who had no history of blood transfusion prior, during or after surgery, not on haemoglobin-boosting or bone marrow suppressing medications, not seropositive to human immunodeficiency virus also without clinical findings suggestive of lymphadenopathy, splenomegaly, ecchymosis and petechiae. Demographic data, Platelet counts and haemoglobin levels before and after surgery were documented and analysed by chi-square test and values were considered to be significant if p < 0.05. Results: A total of 61 patients were included in the study. The mean age of participants was 37.03 ± 16.6 years with range of 7 to 77 years. Majority 82.5% (n = 52) had benign tumors with a leading diagnosis of ameloblastoma followed by ossifying fibroma. In general there was an increase of platelet counts following surgery from the mean of 276.38 ± 109.40 K/uL to 308.51 ± 117.24 K/uL. Looking at benign and malignant separately, following surgery there was an increase of platelet counts for benign tumors (278.87 ± 106.37 to 305.96 ± 123.12) but a decrease for malignant tumors group (282.33 ± 147.03 to 232 ± 78.48). The haemoglobin level changed from the mean of 12.60 ± 1.71 g/dl before surgery to 11.69 ± 1.70 g/dl after surgery. Conclusion: The mean postoperative increase in platelet counts in benign and malignant tumors was d

关键词： Oral Maxillofacial Tumors Pre-Operative Platelets Levels Post-Operative Platelets Levels

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Whispering Gallery Modes Formed by Scattering of an Electromagnetic Plane Wave by Two Cylinders

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Journal of Applied Mathematics and Physics 2017年第4期5卷 785-791页

作者： arnold Abramov Yutao Yue Chunlin Ji Ruopeng Liu Xue Li Juehui Zhou Alexander Kostikov Kuang-chi Institute of Advanced Technology Shenzhen China Shenzhen Kuang-chi Innovative Technology Co. Ltd. Shenzhen China Donbass State Engineering Academy Kramatorsk Ukraine

We report the effect of scattering of electromagnetic plane waves by two cylinders on whispering gallery mode (WGM) formation in a cylinder. WGM can occur because of the presence of additional cylinder scatterers at specific location, while WGMs can only form in a single cylinder for specific cylinder radius and/or wavelength values, the matching accuracy required would be much greater than that required in our model for the additional cylinders locations. Analysis of the general solution to the problem showed that the effect can be explained by the interference of waves scattered by additional cylinders and incident on the main cylinder.

关键词： Scattering Wave Cylinder WGM

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Survival characteristics of fibrolamellar hepatocellular carcinoma:A Surveillance,Epidemiology,and End Results database study

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World Journal of Clinical Oncology 2022年第5期13卷 352-365页

作者： Tomoki Sempokuya arnold Forlemu Muaataz Azawi Krixie Silangcruz Nathalie Khoury Jihyun Ma Linda L Wong Division of Gastroenterology and Hepatology Department of Internal MedicineUniversity of Nebraska Medical CenterOmahaNE 68198United States Division of Gastroenterology and Hepatology Sanford Center for Digestive HealthSioux FallsSD 57105United States Department of Medicine John A.Burns School of MedicineUniversity of Hawaii at ManoaHonoluluHI 96813United States Department of Biostatistics College of Public HealthUniversity of Nebraska Medical CenterOmahaNE 68198United States Department of Surgery John A.Burns School of MedicineUniversity of Hawaii at ManoaHonoluluHI 96813United States

BACKGROUND Fibrolamellar hepatocellular carcinoma(FL-HCC)is a rare and distinct type of hepatocellular carcinoma that frequently presents in an advanced stage in younger patients with no underlying liver ***,there is a limited understanding of factors that impact outcomes in *** To characterize the survival of FL-HCC by age,race,and surgical *** This is a retrospective study of The Surveillance,Epidemiology,and End Results *** identified patients with FL-HCC between 2000-2018 by using an ICD-O-3 site code C22.0 and a histology code 8171/3:Hepatocellular carcinoma,*** addition,demographics,tumor characteristics,types of surgical procedure,stages,and survival data were *** conducted three separate survival analyses by age groups;≤19,20-59,and≥60-year-old,and race;White,Black,Hispanic,Asian and Pacific islanders(API),and surgical types;Wedge resection or segmental resection,lobectomy,extended lobectomy(lobectomy+locoregional therapy or resection of the other lobe),and *** chi-Square test analyzed categorical variables,and continuous variables were examined using the Mann-Whitney U *** Kaplan-Meier survival curve was used to compare *** analysis was done with Cox regression *** We identified 225 FL-HCC patients with a mean age of *** median survival was 34(95%CI:27-41)***≤19-years-old had more advanced disease with positive lymph nodes ***,they received more surgical interventions such as a wedge,segmental resection,lobectomy,extended lobectomy,and *** for≤19 was 85(95%CI:37-137)mo,age 20-59 was 29(95%CI:18-41)mo,and age≥60 years was 12(95%CI:7-31)mo(P<0.001).There were no differences in stage,lymph node status,metastasis status,and surgical treatment among *** median survival were;Whites had 39(95%CI:29-63),Blacks 26(95%CI:5-92),Hispanics 31(95%CI:11-54),and APIs 28(95%CI:5-39)mo(P=0.28).Of 225 patients,111

关键词： Fibrolamellar hepatocellular carcinoma Transplant Race Age Survival

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Nutritional Correlates of Women with a History of Gestational Diabetes and Insulin Resistance in the National Health and Nutrition Examination Survey (NHANES) 2000-2010

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Journal of Diabetes Mellitus 2016年第1期6卷 69-76页

作者： Dotun Ogunyemi Amy Whitten arnold M. Mahesan Anthea B. M. Paul Judy Boura Beaumont Health System Royal Oak USA William Beaumont School of Medicine Oakland University Rochester USA Department of OBGYN St. John Hospital Medical Center Detroit USA

Objective: To evaluate the associations of gestational diabetes (GDM) history with dietary intake, nutritional status, insulin resistance, demographic, and anthropometrical data. Materials & Methods: This cross-sectional study used data from the National Health and Nutrition Examination Survey for the years 2000-2010. Data analysis was based on 290 women who reported a history of GDM compared to 4239 women who denied a GDM history. Insulin resistance [HOMA_IR = (fasting insulin in mU/mL × fasting glucose in mmol/L)/405] was calculated. Pearson correlation, Wilcoxon rank sum tests, Student’s t-tests, and chi-square analysis were used while linear regression assessed independent associations. Results: The median time-lapse from the diagnosis of GDM was 15 years. Women with a GDM history had significantly higher body mass index (BMI), other anthropometric measurements, diastolic blood pressures and insulin resistance. They were also more likely to be Hispanic, have delivered macrosomic infants, and delivered via cesarean. Previous GDM history compared to non-GDM subjects had significantly higher dietary intakes of energy calories, protein, total fat, saturated fatty acids, mono-saturated fatty acids, and cholesterol. Within the entire cohort, increasing insulin resistance was also associated with lower income, less college education, Hispanic or African American ethnicity, obesity, higher systolic and diastolic blood pressures, and with higher dietary cholesterol but lower intake of dietary fiber and micronutrients. Regression analyses showed that GDM history, Hispanic ethnicity, BMI, dietary intake of cholesterol and decreasing income were independently predictive of insulin resistance. Conclusion: The data confirm that even many years after a pregnancy associated with GDM, women with a history of GDM still report significantly higher dietary intakes of energy calories, protein, and fat with no corresponding increase in consumption of dietary fiber or minerals and vit

关键词： Macrosomia Gestational Diabetes Insulin Resistance Nutrition

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定性映射极化恒等式及其在数字图像加密中的应用

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西昌学院学报（自然科学版） 2015年第3期29卷 35-38页

作者：国红军陈黎黎池学东宿州学院智能信息处理实验室安徽宿州234000 安徽大学智能计算与信息处理教育部重点实验室安徽合肥230039

针对信息安全领域的数据加密问题,结合密码学、属性论方法学等相关学科知识,以静止的灰度图像为研究对象,提出了一种基于arnold变换和极化恒等式的数字图像加密算法,并利用Matlab工具对算法进行了仿真实验,实验结果验证了该算法对二维... 详细信息

针对信息安全领域的数据加密问题,结合密码学、属性论方法学等相关学科知识,以静止的灰度图像为研究对象,提出了一种基于arnold变换和极化恒等式的数字图像加密算法,并利用Matlab工具对算法进行了仿真实验,实验结果验证了该算法对二维数字图像加密的可行性和安全性。

关键词：定性映射极化恒等式 arnold变换数字图像加密

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