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Switchgrass Biochar Effects on Plant Biomass and microbial Dynamics in Two Soils from Different Regions

Pedosphere 2015年第3期25卷 329-342页

作者： Charlene N.KELLY Francisco C.CALDERóN Verónica ACOSTA-mARTíNEZ maysoon m.mikha Joseph BENJAmIN David W.RUTHERFORD Colleen E.ROSTAD Western Carolina University Department of Geosciences and Natural Resources331 Stillwell HallCullowheeNC 28723 (USA) U.S.Geological Survey Denver CO 80225 (USA) USDA-ARS Akron CO 80720 (USA) USDA-ARS Lubbock TX 79403 (USA)

Biochar amendments to soils may alter soil function and fertility in various ways, including through induced changes in the microbial community. We assessed microbial activity and community composition of two distinct clayey soil types, an Aridisol from Colorado （CO） in the U.S. Central Great Plains, and an Alfisol from Virginia （VA） in the southeastern USA following the application of switchgrass （Panicum virgatum） biochar. The switchgrass biochar was applied at four levels, 0%,0, 2.5%, 5%, and 10%, approximately equivalent to biochar additions of 0, 25, 50, and 100 t ha^-1, respectively, to the soils grown with wheat （Triticum aestivum） in an eight-week growth chamber experiment. We measured wheat shoot biomass and nitrogen （N） content and soil nutrient availability and N mineralization rates, and characterized the microbial fatty acid methyl ester （FAmE） profiles of the soils. Net N mineralization rates decreased in both soils in proportion to an increase in biochar levels, but the effect was more marked in the VA soil, where net N mineralization decreased from -2.1 to -38.4 mg kg^-1. The 10% biochar addition increased soil pH, electrical conductivity, mehlich- and bicarbonate-extractable phosphorus （P）, and extractable potassium （K） in both soil types. The wheat shoot biomass decreased from 17.7 to 9.1 g with incremental additions of biochar in the CO soil, but no difference was noted in plants grown in the VA soil. The FAmE recovery assay indicated that the switchgrass biochar addition could introduce artifacts in analysis, so the results needed to be interpreted with caution. Non-corrected total FAmE concentrations indicated a decline by 457o and 34% with 10% biochar addition in the CO and VA soils, respectively, though these differences became nonsignificant when the extraction efficiency correction factor was applied. A significant decline in the fungi：bacteria ratio was still evident upon correction in the CO soil with biochar. Switchgrass biochar had the p

关键词： correction factor extraction efficiency fatty acid methyl ester profile nitrogen mineralization soil microbial community soil nutrient availability wheat

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Incorporation of Biochar Carbon into Stable Soil Aggregates:The Role of Clay mineralogy and Other Soil Characteristics

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Pedosphere 2017年第4期27卷 694-704页

作者： Charlene N. KELLY Joseph BENJAmIN Francisco C. CALDERON maysoon m. mikha David W. RUTHERFORD Colleen E. ROSTAD West Virginia University Division of Forestry and Natural Resources337 Percival HallMorgantownWV 26506USA USDA-ARS Central Great Plains Research Station40335 County RoadGGAkronCO 80720USA U.S.Geological Survey MS 408PO Box 25046Building 95Denver Federal CenterDenverCO 80225USA

Aggregation and structure play key roles in water-holding capacity and stability of *** this study,the incorporation of carbon(C) from switchgrass biochar into stable aggregate size fractions was assessed in an Aridisol(from Colorado,USA) dominated by 2:1 clays and an Alfisol(from Virginia,USA) containing weathered mixed 1:1 and 2:1 mineralogy,to evaluate the effect of biochar addition on soil *** biochar was applied at 4 levels,0,25,50,and 100 g kg^(-1),to the soils grown with wheat in a growth chamber *** changes in soil strength and water-holding capacity using water release curves were *** the Colorado soil,the proportion of soil occurring in large aggregates decreased,with concomitant increases in small size *** changes in aggregate size fractions occurred in the Virginia *** the Colorado soil,C content increased from 3.3 to 16.8 g kg^(-1),whereas in them fraction C content increased from 5.7 to 22.6 g kg^(-1) with 100 g kg^(-1)biochar *** the Virginia soil,C content within aggregate size fractions increased for each size fraction,except the>2 000 μm *** greatest increase(from 6.2 to 22.0 g kg^(-1)) occurred in the 53–250 μm *** results indicated that C was incorporated into larger aggregates in the Virginia soil,but remained largely unassociated to soil particles in the Colorado *** addition had no significant effect on water-holding capacity or strength *** biochar to more weathered soils with high native soil organic content may result in greater stabilization of incorporated C and result in less loss because of erosion and transport,compared with the soils dominated by 2:1 clays and low native soil organic content.

关键词： aggregate size fractions, aggregate stability, mineralogy, soil strength, water-holding capacity, weathered soil

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Pump Intensity Dependence of Two-Beam Coupling in Doped Lithium Niobate Crystals

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Chinese Physics Letters 2000年第6期17卷 431-432页

作者： Nouel Y.Kamber XU Jing-Jun Sonia m.mikha SONG Feng ZHANG Guo-Quan ZHANG Xin-Zheng LIU Si-min ZHANG Guang-Yin Photonics Research Center College of Physics ScienceNankai UniversityTianjin 300071

We demonstrated experimentally the dependence of two-beam coupling on the incident pump intensity in our samples of doped LiNbO_(3)*** results show that there is an optimum pump intensity for the signal beam amplification,which can be easily controlled by doping the LiNbO_(3)crystal with suitable concentrations of Fe and damage-resistant dopants such as mg,In,and Zn.

关键词： pump dopant beam

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Soil Carbon Changes Influenced by Soil management and Calculation method

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Open Journal of Soil Science 2013年第2期3卷 123-131页

作者： maysoon m. mikha Joseph G. Benjamin Ardell D. Halvorson David C. Nielsen US Department of Agricultural Agricultural Research Service Central Great Research Station Akron USA US Department of Agricultural Agricultural Research Service Northern Plains Soil Plant Nutrient Research Fort Collins USA

Throughout the years, many studies have evaluated changes in soil organic carbon (SOC) mass on a fixed-depth (FD) basis without considering changes in soil mass caused by changing bulk density (ρb). This study evaluates the temporal changes in SOC caused by two factors: 1) changing SOC concentration;and 2) changing equivalent soil mass (ESm) in comparison with FD. In addition, this study evaluates calculating changes in SOC stock over time using a minimum equivalent soil mass (ESmmin) basis from a single sampling event compared with the FD scenario. A tillage [no-tillage (NT) and chisel plow (CP)]-crop rotation (multiple crop and continuous corn), and irrigation (full and delayed)) study was initiated in 2001 on Weld silt loam soil. After seven years, SOC concentration in the 0 - 30 cm depth was 19.7% greater in 2008 compared with 2001. Standardizing the soil mass of 2001 to the ESm of 2008 for each individual treatment showed an average gain in SOC of 5.8 mg C·ha-1 in 2008 compared with 2001. However, the increase in SOC using ESm was twice the SOC gained with the FD calculation, where some treatments lost SOC after seven years of management. Estimating SOC levels using the ESmmin and, thereby, eliminating the confounding effect of soil ρb indicated that SOC stock was influenced by crop species and their interaction with irrigation, but not by tillage practices. Over all, the ESm calculation appears to be more effective in evaluating SOC stock than the FD calculation.

关键词： Soil Organic Carbon Stock Equivalent Soil mass minimum Equivalent Soil mass Fixed-Depth management Practices

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Efficient Computer Aided Diagnosis System for Hepatic Tumors Using Computed Tomography Scans

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Computers, materials & Continua 2022年第6期71卷 4871-4894页

作者： Yasmeen Al-Saeed Wael A.Gab-Allah Hassan Soliman maysoon F.Abulkhair Wafaa m.Shalash mohammed Elmogy Faculty of Computers and Information Mansoura UniversityMansoura35516Egypt Faculty of Computers&Artificial Intelligence South Valley UniversityHurghada84511Egypt Faculty of Computing and Information Technology King Abdulaziz UniversityJeddah21589Saudi Arabia Faculty of Computers and Artificial Intelligence Benha UniversityBanha13511Egypt

One of the leading causes of mortality worldwide is liver *** earlier the detection of hepatic tumors,the lower the mortality *** paper introduces a computer-aided diagnosis system to extract hepatic tumors from computed tomography scans and classify them into malignant or benign *** hepatic tumors from computed tomography scans is considered a challenging task due to the fuzziness in the liver pixel range,intensity values overlap between the liver and neighboring organs,high noise from computed tomography scanner,and large variance in tumors *** proposed method consists of three main stages;liver segmentation using Fast Generalized Fuzzy C-means,tumor segmentation using dynamic thresholding,and the tumor’s classification into malignant/benign using support vector machines *** performance of the proposed system was evaluated using three liver benchmark datasets,which are mICCAI-Sliver07,LiTS17,and *** proposed computer adided diagnosis system achieved an average accuracy of 96.75%,sensetivity of 96.38%,specificity of 95.20%and Dice similarity coefficient of 95.13%.

关键词： Liver tumor hepatic tumors diagnosis CT scans analysis liver segmentation tumor segmentation features extraction tumors classification FGFCm CAD system

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Control and Synchronization with Known and Unknown Parameters

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Applied mathematics 2016年第3期7卷 292-303页

作者： maysoon m. Aziz Saad Fawzi Al-Azzawi Department of mathematics College of Computer Sciences and Mathematics University of Mosul Mosul Iraq

In this paper, we consider the chaos control for 4D hyperchaotic system by two cases, known & unknown parameters based on Lyapunov stability theory via nonlinear control. We find that there are two cofactors that have an effect on determining any case to achieve the control, the two cofactors are proposed in the control and the matrix that produce from the time derivative of Lyapunov function. In adding, we find some weakness cases in Lyapunov stability theory. For this reason, we design with only one controller and perform a simple change in this control in order to recognize the difference between these cases although all of the controllers are almost similar.

关键词： 4D Hyperchaotic System Control Synchronization Lyapunov Stability Theory Nonlinear Control method

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Altered Levels of Blood Glucose and Serum Lipids in Sudanese Patients with Ovarian Cancer

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Open Journal of Obstetrics and Gynecology 2023年第5期13卷 896-906页

作者： maysoon A. Hassaan Atif H. Khirelsied Tagelsir m. Ali Ahmed A. Agab-Aldour Department of Biochemistry Faculty of Medicine Kordofan University El-Obeid Sudan Department of Biochemistry Faculty of Medicine Al-Baha University Al-Baha Saudi Arabia Department of Obstetrics and Gynecology Faculty of Medicine Al-Baha University Al-Baha Saudi Arabia Department of Pathology Faculty of Medicine Kordofan University El-Obeid Sudan

Background: The etiology of ovarian cancer is not well-understood;numerous metabolomics profiling, epidemiological, and hospital-based case control studies have associated abnormal levels of blood glucose and serum lipids with the risk and the prognosis of various types of cancers including ovarian cancer. The association between the risk of the incidence of ovarian cancer and the alterations in the levels of blood glucose and serum lipids is not well defined. Objective: In this study we aimed to compare the levels of blood glucose, triacylglycerols, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol in patients with different stages of ovarian cancer and healthy controls to determine how they relate to the risk and prognosis of ovarian cancer. methodology: In a case-control cross sectional study, we enrolled ninety-nine Sudanese women, diagnosed with ovarian cancer but had not received any kind of treatment as the study group, and a control group of forty-one age-matched, apparently healthy women. The patients were classified according to the International Federation of Obstetricians and Gynecologists staging system into two groups: early stages (stage I & II) and late stages (stages III & IV). Blood glucose and serum lipids;triacylglycerols, total cholesterol, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol were determined by enzymatic colorimetric methods using commercially available analytical kits. The IBm SPSS version 20 software was used for statistical analysis. A mann-Whitney U test was used for comparison of the median concentrations of blood glucose, triacylglycerols, total cholesterol, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol in the study groups. Logistic regression model was used to estimate the relative risk of ovarian cancer in relation to levels of blood glucose and serum lipids. P value of 0.05 was considered significant. Results: Our data indicated significa

关键词： Blood Glucose Cholesterol Ovarian Cancer Serum Lipids Triacylglycerol

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Water Deficit Stress Effects on Corn (<i>Zea mays</i>, L.) Root:Shoot Ratio

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Open Journal of Soil Science 2014年第4期4卷 151-160页

作者： J. G. Benjamin D. C. Nielsen m. F. Vigil m. m. mikha F. Calderon Central Great Plains Research Station USDA-ARS Akron USA

A study was conducted at Akron, CO, USA, on a Weld silt loam in 2004 to quantify the effects of water deficit stress on corn (Zea mays, L.) root and shoot biomass. Corn plants were grown under a range of soil bulk density and water conditions caused by previous tillage, crop rotation, and irrigation management. Water deficit stress (Dstress) was quantified by the number of days when the water content in the surface 0.3 m deviated from the water content range determined by the Least Limiting Water Range (LLWR). Root and shoot samples were collected at the V6, V12, and R1 growth stages. There was no significant correlation between Dstress and shoot or root biomass at the V6 growth stage. At the V12 and R1 growth stages, there were negative, linear correlations among Dstress and both root biomass and shoot biomass. The proportional decrease of shoot biomass was greater than the proportional decrease in root biomass, leading to an increase in the root:shoot ratio as water deficit stress increased at all growth stages. Determining restrictive soil conditions using the LLWR may be useful for evaluating improvement or degradation of the soil physical environment caused by soil management.

关键词： Shoot Ratio Least Limiting Water Range Water Stress Corn Root Development Soil Environment

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