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Do model choice and sample ratios separately or simultaneously influence soil organic matter prediction?

International Soil and Water Conservation Research 2022年第3期10卷 470-486页

作者： Kingsley John Yassine Bouslihim Kokei Ikpi Ofem lahcen Hssaini Rachid Razouk Paul Bassey Okon Isong Abraham Isong Prince Chapman Agyeman Ndiye Michael Kebonye Chengzhi Qin Department of Soil Science and Soil Protection Faculty of AgrobiologyFoodand Natural ResourcesCzech University of Life SciencesKamýcka 12916500PragueCzech Republic National Institute of Agricultural Research Morocco Department of Soil Science Faculty of AgricultureForestry and Wildlife Resources ManagementUniversity of CalabarPMB 1115540004Etta Agbo RoadCalabarNigeria State Key Laboratory of Resources and Environmental Information System Institute of Geographical Sciences and Natural Resources ResearchCASBeijing100101China

This study was performed to examine the separate and simultaneous influence of predictive models’choice alongside sample ratios selection in soil organic matter(SOM).The research was carried out in northern Morocco,characterized by relatively cold weather and diverse geological *** dataset herein used accounted for 1591 soil samples,which were randomly split into the following ratios:10%(∼150 sample ratio),20%(∼250 sample ratio),35%(∼450 sample ratio),50%(∼600 sample ratio)and 95%(∼1200 sample ratio).Models herein involved were ordinary kriging(OK),regression kriging(RK),multiple linear regression(MLR),random forest(RF),quantile regression forest(QRF),Gaussian process regression(GPR)and an ensemble *** findings in the study showed that the accuracy of SOM prediction is sensitive to both predictive models and sample *** combined with 95%sample ratio performed equally to RF in conjunction with all the sample ratios,as the latter did not show much sensitivity to sample *** results revealed that RF with a∼10%sample ratio could also be optimum for predicting SOM in the study *** conclusion,the findings herein reported could be instrumental for producing cost-effective detailed and accurate spatial estimation of SOM in other ***,they could serve as a baseline study for future research in the region or ***,we recommend conducting series of simulation of all possible combinations between various predictive models and sample ratios as a preliminary step in soil organic matter prediction.

关键词： Analysis of variance Agriculture Digital soil mapping Predictive mapping Mediterranean

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Mapping soil nutrients via different covariates combinations:theory and an example from Morocco

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Ecological Processes 2022年第1期11卷 302-318页

作者： Kingsley John Yassine Bouslihim Isong Abraham Isong lahcen Hssaini Rachid Razouk Ndiye M.Kebonye Prince C.Agyeman Vit Penížek Tereza Zádorová Department of Soil Science and Soil Protection Faculty of AgrobiologyFoodand Natural ResourcesCzech University of Life SciencesKamýcká12916500 PragueCzech Republic National Institute of Agricultural Research RabatMorocco Department of Soil Science University of CalabarCalabarNigeria

Background:Mapping of soil nutrients using different covariates was carried out in northern *** study was undertaken in response to the region’s urgent requirement for an updated soil *** aimed to test various covariates combinations for predicting the variability in soil properties using ordinary kriging and kriging with external ***:A total of 1819 soil samples were collected at a depth of 0–40 cm using the 1-km grid sampling *** were screened for their pH,soil organic matter(SOM),potassium(K_(2)O),and phosphorus(P_(2)O_(5))using standard laboratory *** attributes(T)computed using a 30-m resolution digital elevation model,bioclimatic data(C),and vegetation indices(V)were used as covariates in the *** targeted soil property was modeled using covariates separately and then combined(e.g.,pH~T,pH~C,pH~V,and pH~T+C+V).k=tenfold cross-validation was applied to examine the performance of each employed *** statistical parameter RMSE was used to determine the accuracy of different ***:The pH of the area is slightly above the neutral level with a corresponding 7.82%of SOM,290.34 ppm of K_(2)O,and 100.86 ppm of P_(2)O_(5).This was used for all the selected targeted soil *** a result,the studied soil properties showed a linear relationship with the selected ***,SOM,and K 2O presented a moderate spatial autocorrelation,while P2O5 revealed a strong *** cross-validation result revealed that soil pH(RMSE=0.281)and SOM(RMSE=9.505%)were best predicted by climatic variables.P_(2)O_(5)(RMSE=106.511 ppm)produced the best maps with climate,while K_(2)O(RMSE=209.764 ppm)yielded the best map with terrain ***:The findings suggest that a combination of too many environmental covariates might not provide the actual variability of a targeted soil *** demonstrates that specific covariates with close relationships with certain soil properties might perform bet

关键词： Soil mapping Environmental variables Agriculture Soil properties Soil management

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Supplementing Conventional Treatment with Pycnogenol(R) May Improve Hepatitis C Virus-Associated Type 2 Diabetes:A Mini Review

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Journal of Clinical and Translational Hepatology 2016年第3期4卷 228-233页

作者： Sayeh Ezzikouri Fatima Zahra Jadid Salsabil Hamdi lahcen Wakrim Kyoko Tsukiyama-Kohara Soumaya Benjelloun Virology Unit Viral Hepatitis Laboratory Institut Pasteur du Maroc Casablanca Morocco Virology Unit Immunovirology Laboratory Institut Pasteur du Maroc Casablanca Morocco Laboratory of Animal Hygiene Joint Faculty of Veterinary MedicineKagoshima University Kagoshima Japan Transboundary Animal Diseases Centre Joint Faculty of Veterinary MedicineKagoshima University Kagoshima Japan

Hepatitis C virus (HCV) infection and type 2 diabetes mellitus (T2DM) present a significant health burden,with increasing complications and mortality rates ***(R) (PYC),a natural product,possesses antidiabetic and antiviral properties that may improve HCV-associated *** this review,we present previously published data on the effectiveness of PYC against HCV replication and *** believe that supplementing conventional treatment with PYC may improve the current HCV therapy,attenuate HCV-associated T2DM,and reduce the risk of complications such as cirrhosis or hepatocellular carcinoma and cardiovascular disease.

关键词： T2DM Hepatitis C Pycnogenol(R) Complementary medicine

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Evaluation of Stress among 100 Moroccan Orthodontists

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Open Journal of Stomatology 2011年第1期1卷 1-6页

作者： lahcen Ousehal Laila Lazrak Karima Hassani 不详

Stress is associated with many professions including dental surgery. It has been the subject of several studies. However, its evaluation in orthodontics has not been sufficiently studied. Some studies that have described the stressful aspects of dentistry have reported the involvement of orthodontists, but no studies have been conducted in Morocco. The purpose of this study is to evaluate professional stress in orthodontics in Morocco. We conducted a descriptive and sectional study through a survey distributed to one hundred private orthodontist practitioners in Casablanca, Morocco. Stress signs were observed in 44% of the orthodontists. The most prominent factors of stress in orthodontics are related to patients and time. Experience of practitioners has been identified as the only factor significantly influencing their perception of stress. Thus, clinical competence and proper management of practice are the best ways to deal with daily stress in orthodontic practice.

关键词： Orthodontics Stress Time Management

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The Role of DNA Mismatch Repair and Recombination in the Processing of DNA Alkylating Damage in Living Yeast Cells

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Advances in Bioscience and Biotechnology 2015年第6期6卷 408-418页

作者： Hernan Flores-Rozas lahcen Jaafar Ling Xia College of Pharmacy and Pharmaceutical Sciences Florida A&M University Tallahassee USA Institute of Molecular Medicine and Genetics Georgia Regents University Augusta USA

It is proposed that mismatch repair (MMR) mediates the cytotoxic effects of DNA damaging agents by exerting a futile repair pathway which leads to double strand breaks (DSBs). Previous reports indicate that the sensitivity of cells defective in homologous recombination (HR) to DNA alkylation is reduced by defects in MMR genes. We have assessed the contribution of different MMR genes to the processing of alkylation damage in vivo. We have directly visualized recombination complexes formed upon DNA damage using fluorescent protein (FP) fusions. We find that msh6 mutants are more resistant than wild type cells to MNNG, and that an msh6 mutation rescues the sensitivity of rad52 strains more efficiently than an msh3 mutation. Analysis of RAD52-GFP tagged strains indicate that MNNG increases repair foci formation, and that the inactivation of the MHS2 and MSH6 genes but not the MSH3 gene result in a reduction of the number of foci formed. In addition, in the absence of HR, NHEJ could process the MNNG-induced DSBs as indicated by the formation of NHEJ-GFP tagged foci. These data suggest that processing of the alkylation damage by MMR, mainly by MSH2-MSH6, is required for recruitment of recombination proteins to the damage site for repair.

关键词： DNA Mismatch Repair Recombination DNA Damage Non-Homologous End Joining

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Intensity Distribution of the Finite Olver Beams through a Paraxial ABCD Optical System with an Aperture of Basis Annular Aperture

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Optics and Photonics Journal 2015年第12期5卷 354-368页

作者： Salima Hennani lahcen Ez-Zariy Abdelmajid Belafhal Laboratory of Nuclear Atomic and Molecular Physics Department of Physics Faculty of Sciences Choua&#239 b Doukkali University El Jadida Morocco

Based on the Collins diffraction formula and by means of the expansion of a hard aperture function into a finite sum of complex Gaussian functions, two analytical approaches of the Finite Olver beams (FOBs) passing through a paraxial ABCD optical system with a circular annular aperture or a rectangular one are developed in this paper. The propagation properties of the FOBs through an unapertured ABCD optical system or through this last with a circular (or rectangular) aperture or a circular (or rectangular) black screen are deduced, from the main results, as particular cases. Also, the characteristics of Finite ordinary Airy beam passing through the all considered optical systems are derived here that correspond to zeroth-order of the FOBs. According to the predicted formulas, computer simulation examples are given to deepen the understanding of the characteristics of the FOBs passing through some optical systems of annular aperture basis.

关键词： Diffraction Finite Olver Beams Airy Beams ABCD Optical System Circular Annular Aperture Rectangular Annular Aperture Circular Black Screen Rectangular Black Screen

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Study of Tungsten Phosphate Glasses Containing Fe<sub>2</sub>O<sub>3</sub>

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New Journal of Glass and Ceramics 2019年第3期9卷 33-49页

作者： Hicham Es-Soufi lahcen Bih Meyrem Benzineb Equipe de Physico-Chimie de la Matière Condensée PCMC Faculté des Sciences de Meknès Université Moulay Ismail Meknès Morocco Département matériaux et procédés ENSAM Meknès Université Moulay Ismail Meknès Morocco

Glasses of the compositions 20Li2O-(50 - x)Li2WO4-xFe2O3-30P2O5 where (x = 0, 1, 5, 8, 10, 15 mol%) were elaborated by the melt-quenching route. Synthesized glasses are characterized using X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), differential scanning calorimetric?(DSC), and density determination. The XRD patterns confirmed the?amorphous nature of samples, and IR spectra showed the structural groups and highlight the depolymerization of phosphate network with the introduction of iron oxide. It is found that the structural unit Q2 converts to Q1 and Q0 as Fe2O3 replaces Li2WO4. Chemical durability tests on the glasses have shown that the compositions containing pyrophosphate (Q1) and orthophosphate (Q0) units are more water-resist. The electrical conductivity measurements were performed by complex impedance spectroscopy in the frequency range of 20 - 106 Hz at various temperatures from ambient to 400°C. It is found that the conductivity is activated thermally and follows an Arrhenius law. The obtained electrical data were analyzed by the modulus formalism and dielectric formalism. The determined asymmetric nature of? spectra suggested that the relaxation behavior is non-Debye and characterized by the stretched exponent parameter

关键词： Phosphate Glasses Thermal Analysis Structure Electrical Conductivity

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Discrete Pseudo Almost Periodic Solutions for Some Difference Equations

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Advances in Pure Mathematics 2011年第4期1卷 118-127页

作者： Elhadi Ait Dads Khalil Ezzinbi lahcen Lhachimi University Cadi Ayyad Faculty of Sciences Semlalia Department of Mathematics Marrakesh Morocco

In this work, we study the existence and uniqueness of pseudo almost periodic solutions for some difference equations. Firstly, we investigate the spectrum of the shift operator on the space of pseudo almost periodic sequences to show the main results of this work. For the illustration, some applications are provided for a second order differential equation with piecewise constant arguments.

关键词： Difference Equations Pseudo Almost Periodic Sequences Schift Operator

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Propagation Properties of Finite Olver-Gaussian Beams Passing through a Paraxial ABCD Optical System

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Optics and Photonics Journal 2015年第9期5卷 273-294页

In this paper, an exact analytical propagation formula of Finite Olver-Gaussian Beams (FOGBs) passing through a paraxial ABCD optical system is developed and some numerical examples are performed. The propagation properties of the FOGBs through general optical systems characterized by given ABCD matrix are studied on the basis of the generalized Huygens-Fresnel diffraction integral, which permits to show the behavior of this laser beams family and its properties de-pending of the laser parameters. This research is of interest to prove some investigations done in the past by other researchers.

关键词： Finite Olver-Gaussian Beams Generalized Huygens-Fresnel Diffraction ABCD Optical Systems

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New and Intelligent Embedding Algorithm and New Techniques for Information Hiding in Web Pages

New and Intelligent Embedding Algorithm and New Techniques f...

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作者： Mohamed lahcen Bensaad 湖南大学

学位级别：硕士

Nowadays, the fascinating art of Information hiding is one of the hottest reach fields due to its significance and importance in solving many rising problems in the ear of information and internet. Digital watermarking, as a branch of information hiding, is a promising technique for the protection of intellectual property rights. This technology is mainly advanced for multimedia but the same has not been done for text. Because of the varieties of file formats, there has been no attempt to make one unified general embedding algorithm which can be applied to different types of data. The most general method of embedding a message M into a set of cover-objects C is to break down M into small units (bits) Mi then embed each unit Mi into one cover-object Ci, which is in most cases, if not always, selected sequentially from the cover data stream. This way of selecting the cover-objects Ci can be enhanced to make it more intelligent by studying the properties and features of the different kinds of Ci and use them accordingly, and that is what will be shown here. Web pages, as one of the many kinds of file formats, can be used as cover documents to server different purposes. In this work, some new techniques are presented to show how to hide information in web pages using some features of the markup language used to describe these pages. Most of these techniques use the white space to hide information or some varieties of the language in representing elements. Experiments on a very small page and analysis of five thousands web pages show that these techniques provide a wide bandwidth available for hiding a quite big amount of data. Tests show that the use of the presented techniques applying the new proposed embedding algorithm will enhance the robustness of the hidden information. This work might serve to form a solid base to develop robust watermarking algorithms not only for web pages but also for all other types of data.

关键词： Steganography Information Hiding Covert Communication Digital Watermarking Robust HTML and Web Pages

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