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Modelling Plant Disease Risk Areas Based on Brazilian Climate Change scenarios

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Journal of Environmental science and Engineering 2011年第3期5卷 333-343页

作者： M. de C. Alves L.G. de Carvalho E.A. Pozza L. sanches J.C. de s. maia Department of soil and Rural Engineering Federal University of Mato Grosso Brazil Av. Fernando Correa da Costa Boa Esperanca 2367 Cuiaba Brazil. Department of Engineering Federal University of Lavras Brazil Cx. 3037. Department of Phytopathology Federal University of Lavras Brazil Cx. 3037. Department of sanitary and Environmental Engineering Federal University ofMato Grosso Av. Fernando Correa da Costa Boa Esperanga 2367 Cuiaba Brazil.

Geosciences and statistics were applied to develop predictive models to study the areas of risk to soybean rust （Phakopsora pachyrhizi sydow） in soybean （Glycine max L.）, coffee leaf rust （Hemileia vastatrix Berk ＆ Br） in coffee and Black sigatoka （Mycosphaerella fijiensis var. difformis） in banana, considering to Brazilian climatic characterization and distribution of soybean, coffee and banana crops in the period of observed data of 1950 to 2000 and A2 climate change scenarios of simulated data of 2020, 2050 and 2080. The technique of principal components allowed generating 1 variable based on 57 variables in order to determine an index explaining 87%, 88% and 90% of the variability of soybean, coffee and banana crops in Brazilian municipal districts. The climatic model of each disease was used to generate the zoning of the coffee rust, soybean rust and black sigatoka based on temperature and leaf wetness. Areas of favorability of the diseases were plotted inside to the main coffee, soybean and banana growing in Brazil. The applied methodology enabled to visualize the variation of favorable areas of epidemics according to the studied scenarios of climate change.

关键词： Plant disease geographic information systems statistics agroecosystems Brazil.

Relativistic Landau quantization in the spiral dislocation spacetime

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Communications in Theoretical Physics 2021年第2期73卷 68-72页

作者： A V D M maia K Bakke Departamento de Fisica Universijade Federal da ParaibaCaixa Postal 500858051-900Joao PessoaPBBrazil

We analyse the interaction of a relativistic electron with a uniform magnetic field in the spiral dislocation *** show that analytical solutions to the Dirac equation can be obtained,where the spectrum of energy corresponds to the relativistic Landau *** also analyse the influence of the spiral dislocation on the relativistic Landau levels by showing that there exists an analogue of the Aharonov–Bohm effect for bound states.

关键词： spiral dislocation spacetime relativistic Landau quantization Aharonov-Bohm effect relativistic wave equations Dirac equation

Novel experimental techniques to assess the time-dependent deformations of geosynthetics under soil confinement

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第2期13卷 410-419页

作者： Carina maia Lins Costa Jorge Gabriel Zornberg Department of Civil Engineering Federal University of Rio Grande do NorteAv.Senador Salgado Filho 3000NatalRio Grande do Norte59078-970Brazil Department of Civil Architectural and Environmental Engineering The University of Texas at Austin301 E.Dean KeetonAustinTX78712-0280USA

A new experimental approach to assess the impact of soil confinement on the long-term behavior of geosynthetics is presented in this *** experimental technique described herein includes a novel laboratory apparatus and the use of different types of tests that allow generation of experimental data suitable for evaluation of the time-dependent behavior of geosynthetics under soil *** soil-geosynthetic interaction equipment involves a rigid box capable of accommodating a cubic soil mass under plane strain conditions.A geosynthetic specimen placed horizontally at the mid-height of the soil mass is subjected to sustained vertical pressures that,in turn,induce reinforcement axial loads applied from the soil to the *** previously reported studies on geosynthetic behavior under soil confinement,the equipment was found to be particularly *** minor setup modifications,not only interaction tests but also in-isolation geosynthetic stress relaxation tests and soil-only tests under a constant strain rate can be conducted using the same ***,the time histories of the reinforcement loads and corresponding strains are generated throughout the *** from typical tests conducted using sand and a polypropylene woven geotextile are presented to illustrate the proposed experimental *** testing procedure was found to provide adequate measurements during tests,including good repeatability of test *** soilegeosynthetic interaction tests were found to lead to increasing geotextile strains with time and decreasing reinforcement tension with *** test results highlighted the importance of measuring not only the time history of displacements but also that of reinforcement loads during *** approach of using different types of tests to analyze the soilegeosynthetic interaction behavior is an innovation that provides relevant insight into the impact of soil confinement on the time-dependent deformations of geos

关键词： Geosynthetics Geotextile Creep stress relaxation Reinforced soil Long-term deformation

Global stability for a Heroin Model with Age-Dependent susceptibility

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Journal of systems science & Complexity 2015年第6期28卷 1243-1257页

作者： FANG Bin LI Xuezhi MARTCHEVA maia CAI Liming Department of Mathematics Xinyang Normal University Beijing Institute of Information and Control Department of Mathematics University of Florida

This paper considers global asymptotic properties for an age-structured model of heroin use based on the principles of mathematical epidemiology where the incidence rate depends on the age of susceptible individuals. The basic reproduction number of the heroin spread is obtained. It completely determines the stability of equilibria. By using the direct Lyapunov method with Volterra type Lyapunov function, the authors show that the drug-free equilibrium is globally asymptotically stable if the basic reproduction number is less than one, and the unique drug spread equilibrium is globally asymptotically stable if the basic reproduction number is greater than one.

关键词： Age-structured basic reproduction number equilibrium global stability heroin model

Intestinal ultrasound as a non-invasive tool to monitor inflammatory bowel disease activity and guide clinical decision making

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World Journal of Gastroenterology 2023年第15期29卷 2272-2282页

作者： Michael T Dolinger maia Kayal Department of Pediatric Gastroenterology Icahn School of Medicine at Mount SinaiNew YorkNY 10029United States Department of Medicine Division of GastroenterologyIcahn School of Medicine at Mount SinaiNew YorkNY 10029United States

Intestinal ultrasound(IUs)is a non-invasive,real-time,cross-sectional imaging tool that can be used at the point-of-care to assess disease activity in patients with Crohn’s disease or ulcerative *** promotes quick and impactful treatment decisions that can modify disease progression and enhance patient *** review will summarize the technical aspects of IUs,the evidence to support the use of IUs in disease activity monitoring,the comparison of IUs to current standard of care monitoring modalities such as colonoscopy and calprotectin,and the optimal positioning of IUs in a tight-control monitoring strategy.

关键词： Crohn’s disease Ulcerative colitis Disease monitoring Intestinal ultrasound

Numerical modeling of local scour of non-uniform graded sediment for two arrangements of pile groups

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International Journal of sediment Research 2023年第4期38卷 597-614页

作者： saeid Okhravi saeed Gohari Mahdi Alemi Rodrigo maia Institute of Hydrology Slovak Academy of Sciences Department of Water Engineering College of Agriculture Bu-Ali Sina University Departamento de Engenharia Civil Faculdadede Engenharia Universidade do Porto CIIMAR-Interdisciplinary Centre of Marine and Environmental Research University of Porto

A three-dimensional(3D) non-hydrostatic numerical model is established to investigate local scour around four aligned circular piles in uniform and non-uniform sediment mixtures and to provide information for improving scour countermeasures design. In the current study, unsteady Reynolds averaged Navier-stokes(URANs) equations along with a Re-normalization Group(RNG) k-ε model were applied to simulate the flow field. A non-uniform sediment transport model was applied to estimate the bedload transport. The simulations lasted up to 8 h. The laboratory results of a reference single pile case in uniform and non-uniform sediment were utilized to validate the simulation results of bed elevation changes and time evolution of scour depth and reflected a good agreement. The influence of pile spacing for two arrangements of pile groups, one column(tandem) and two columns(nontandem) of four aligned piles, on spatial/temporal variations of the bed surface in both sediment bed configurations are discussed in detail. The results reveal the significant effects of the pile spacing on the flow field and patterns of scour hole formation and sediment deposition. In general, lower pile spacing results in more scour upstream of the front pile(s) and shifts deposition more downstream due to the existence of higher energy in the wake region of the piles for both sediment types. side scouring dominates for non-uniform sediment around each pile due to flow deviating because of the presence of relatively larger particles in front of the pile(s). For non-uniform sediment, deposition begins to develop at the exit area of the scour hole and enhances boundary resistance to scour. The knowledge gained from this study is suitable for the accurate determination of riprap dimensions around the front pile(s)and rear piles in a pile group.

关键词： Local bridge pier scour Non-uniform sediment Numerical modeling Pile groups Pile spacing sediment transport

MARDIA's COEFFICIENT OF KURTOsIs IN ELLIPTICAL POPULATIONs

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Acta Mathematicae Applicatae sinica 1990年第4期6卷 289-294页

作者： maia BERKANE P.M.BENTLER University of California Los AngelesUniversity of CaliforniaLos Angeles

Mardia (1970) defined a measure of multivariate kurtosis and derived its asymptotic distributionfor samples from a multivariate normal population. some new results on elliptical distributions areused to extend Mardia's results to samples from an elliptical distribution. These results provide amethod for testing hypotheses on the kurtosis parameter of elliptical distributions. An appendixprovides extensions of Kendall and stuart's (1977) standard errors of bivariate moments to the thirdand fourth order.

关键词： MARDIA’s COEFFICIENT OF KURTOsIs IN ELLIPTICAL POPULATIONs 云脚

Factors predicting poor prognosis in ischemic colitis

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World Journal of Gastroenterology 2006年第30期12卷 4875-4878页

作者： Ramón A■ón Marta maia Boscá Vicente sanchiz Joan Tosca Pedro Almela Cirilo Amorós Adolfo Benages Department of Gastroenterology of the University Clinical Hospital of Valencia University of Valencia Spain

AIM： To determine the clinical, analytical and endoscopic factors related to ischemic colitis （IC） severity. METHODs： A total of 85 patients were enrolled in a retrospective study from January 1996 to May 2004. There were 53 females and 32 males （age 74.6 ± 9.4 years, range 45-89 years）. The patients were diagnosed as IC. The following variables were analyzed including age, sex, period of time from the appearance of symptoms to admission, medical history, medication, stool frequency, clinical symptoms and signs, blood tests （hemogram and basic biochemical profile）, and endoscopic findings. Patients were divided in mild IC group and severe IC group （surgery and/or death）. Qualitative variables were analyzed using chi-square test and parametric data were analyzed using student＇s t test （P 〈 0.05）. REsULTs： The mild IC group was consisted of 69 patients （42 females and 27 males, average age 74.7 ± 12.4 years）. The severe IC group was composed of 16 patients （11 females and 5 males, average age of 73.8 ± 12.4 years）. One patient died because of failure of medical treatment （no surgery）, 15 patients underwent surgery （6 after endoscopic diagnosis and 9 after peroperatory diagnosis）. Eight of 85 patients （9.6%） died and the others were followed up as out-patients for 9.6 ± 3.5 mo. Demographic data, medical history, medication and stool frequency were similar in both groups （P 〉 0.05）. seriously ill patients had less hematochezia than slightly ill patients （37.5% vs 86.9%, P = 0.000）. More tachycardia （45.4% vs 10.1%, P = 0.011） and a higher prevalence of peritonism signs （75% vs 5.7%, P = 0.000） were observed in the severe IC group while the presence and intensity of abdominal pain were similar between two groups. Two patients with severe IC had shock when admitted. Regarding analytical data, more seriously ill patients were found to have anemia and hyponatremia than the mildly ill patients （37.5% vs 10.1%, P = 0.014 and 46.6% vs 14.9%, P = 0.012, respectively）. steno

关键词： Ischemic colitis Hematochezia Tachycardia Peritonism Anemia Hyponatremi stenosis

stability and convergence of the variable directions difference scheme for one nonlinear two-dimensional model

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International Journal of Biomathematics 2015年第5期8卷 31-51页

作者： Temur Jangveladze Zurab Kiguradze Mikheil Gagoshidze maia Nikolishvili Ilia Vekua Institute of Applied Mathematics of Ivane Javakhishvili Tbilisi state University2 University street 0186 Tbilisi Georgia Ilia Vekua Institute of Applied Mathematics of Ivane Javakhishvili Tbilisi state University 2 University street 0186 Tbilisi Georgia sokhumi state University12 Politkovskaya street 0186 Tbilisi Georgia Ivane Javakhishvili Tbilisi state University 2 University street 0186 Tbilisi Georgia

The system of two-dimensional nonlinear partial differential equations is considered. This system describes the vein formation in meristematic tissues of young leaves. Variable directions difference scheme is constructed and investigated. Absolute stability regarding space and time steps of scheme is shown. The convergence statement for the constructed scheme is proved. Rate of convergence is given. Various numerical experiments are carried out and results of some of them are considered in this paper. Comparison of numerical experiments with the results of the theoretical investigation is given too.

关键词： Variable directions difference scheme nonlinear partial differential equations stability convergence vein formation.