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Applying Source Parameter Imaging (SPI) to Aeromagnetic Data to Estimate Depth to Magnetic Sources in the Mamfe Sedimentary Basin

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International Journal of Geosciences 2024年第1期15卷 1-11页

作者： eric n. ndikum Charles T. Tabod Department of Physics HTTC Bambili The University of Bamenda Bamenda Cameroon Department of Fundamental Sciences Higher Technical Teacher Training College (HTTTC) Bamenda Cameroon Department of Physics University of Yaoundé 1 Yaoundé Cameroon Department of Physics Faculty of Science The University of Bamenda Bamenda Cameroon

Aeromagnetic data over the Mamfe Basin have been processed. A regional magnetic gridded dataset was obtained from the Total Magnetic Intensity (TMI) data grid using a 3 × 3 convolution (Hanning) filter to remove regional trends. Major similarities in magnetic field orientation and intensities were observed at identical locations on both the regional and TMI data grids. From the regional and TMI gridded datasets, the residual dataset was generated which represents the very shallow geological features of the basin. Processing this residual data grid using the Source Parameter Imaging (SPI) for magnetic depth suggests that the estimated depths to magnetic sources in the basin range from about 271 m to 3552 m. The highest depths are located in two main locations somewhere around the central portion of the study area which correspond to the area with positive magnetic susceptibilities, as well as the areas extending outwards across the eastern boundary of the study area. Shallow magnetic depths are prominent towards the nW portion of the basin and also correspond to areas of negative magnetic susceptibilities. The basin generally exhibits a variation in depth of magnetic sources with high, average and shallow depths. The presence of intrusive igneous rocks was also observed in this basin. This characteristic is a pointer to the existence of geologic resources of interest for exploration in the basin.

关键词： Mamfe Basin Aeromagnetic Data Source Parameter Imaging (SPI) Depth to Magnetic Sources

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Regional Intrusive Signature from the Cameroon Coastal Basins to Bioko Island in Equatorial Guinea (Gulf of Guinea) Using Gravity Studies

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Journal of Geoscience and Environment Protection 2023年第1期11卷 1-14页

The Gulf of Guinea constitutes an area of great petroleum potential yet with very limited geophysical research information. Consequently in this study, a Bouguer anomaly map has been computed from gravity data covering regions stretching from the Cameroon coastal basins to Bioko island (formerly Fernando Po) which is part of Equatorial Guinea. The data were further processed for Source Edge Detection (SED), Euler 3D deconvolution, 3D surface oriented models and 3D voxel solutions. The results confirmed the presence of previously identified intrusive bodies around the Douala and Kribi/Campo sedimentary sub-basins and went ahead to suggest a probable continuity between these two. A possible extension of this body offshore the Gulf of Guinea right up to Bioko island with very striking similarities was also highlighted and it shows characteristic variations in the depth to the surface of the body at different locations.

关键词： Intrusive Body 3D Surface-Oriented Model Gulf of Guinea

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First episode psychosis with extrapyramidal signs prior to antipsychotic drug treatment

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Chinese Science Bulletin 2011年第32期56卷 3361-3371页

作者： HOnER William G LAnG Donna J KOPALA Lili C MACEWAn G William SMITH Geoffrey n CHEn eric Y H CHAn Raymond C K Department of Psychiatry University of British Columbia Vancouver BC Canada Department of Radiology University of British Columbia Vancouver BC Canada Department of Psychiatry Dalhousie University Halifax NS Canada Department of Psychiatry University of Hong Kong Key Laboratory of Mental Health Institute of Psychology Chinese Academy of Sciences

Extrapyramidal movement disorders are common in chronic schizophrenia, and may be an intrinsic feature of the illness as well as related to antipsychotic drug treatment. Similar dysfunctions at illness onset may have implications for outcome, and for under- standing the mechanisms of illness. The objectives were to examine the clinical correlates of pre-treatment movement disorders at first episode of psychosis, and determine associations with neuropsychological function and striatal structure. never medicated subjects were recruited from consecutive admissions to Early Psychosis Programs with defined catchment areas in Hong Kong, China, and Halifax, Canada. Standardized clinical, neuropsychological and brain imaging assessments were carried out at baseline and following acute and long term treatment with typical or atypical antipsychotic drugs. At the Hong Kong site, we studied 84 subjects with first episode psychosis (n = 10 with EPS). At the Halifax site, we studied 40 subjects with first episode psychosis (n = 17 with EPS), and 23 healthy comparison subjects. Subjects with movement disorders prior to treatment (EPS+) had higher total PAnSS scores at baseline (mean elevation 19.9% Hong Kong, P = 0.016; 14.7% Halifax, P = 0.049). In subjects treated with atypical antipsychotics (all Halifax), EPS+ status at baseline predicted more movement disorders at long term follow up (P = 0.0005). In both cohorts, EPS+ subjects had poorer acute symptomatic treatment response assessed with the PAnSS (Hong Kong P = 0.005; Halifax P = 0.017). neuropsychological impairment related to executive dysfunction appeared greater in a small sam- ple of EPS+ subjects (Hong Kong, effect size 0.26-0.27, P n EPS+ compared with EPS-subjects (Halifax P = 0.042), and correlations between striatal volumes and age were different in the EPS+ group. In conclu- sion, pre-treatment EPS is present in a substantial minority of subjects with first episode psych

关键词：药物治疗精神病体外症状运动障碍每股收益神经功能精神分裂症

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Effect of Baroclinicity on Vortex Axisymmetrization. Part Ⅱ:Baroclinic Basic Vortex

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Advances in Atmospheric Sciences 2014年第6期31卷 1267-1278页

作者： Jiayi PEnG Melinda S.PEnG Tim LI eric HEnDRICKS IMSG at Environmental Modeling Center NCEP/NOAA College Park Maryland USA naval Research Laboratory Monterey California USA Department of Meteorology and IPRC University of Hawaii at Manoa Honolulu Hawaii USA

The effect of baroclinicity on vortex axisymmetrization is examined within a two-layer dynamical *** basic state vortices are constructed with varying degrees of baroclinicity：（i） barotropic,（ii） weak baroclinic,and （iii） strong *** linear and nonlinear evolution of wavenumber-2 baroclinic disturbances are examined in each of the three basic state *** results show that the radial propagating speed of the vortex Rossby wave at the lower level is larger with the stronger baroclinicity,resulting in a faster linear axisymmetrization process in the stronger baroclinic *** is found that the nonlinear axisymmetrization process takes the longest time in the strongest baroclinic vortex among the three different basic vortices due to the weaker kinetic energy transfer from asymmetric to symmetric circulations at the lower level.A major finding in this study is that the same initial asymmetric perturbation can have different effects on symmetric vortices depending on the initial vortex *** numerical weather prediction models,this implies that there exists a sensitivity of the subsequent structural and intensity change solely due to the specification of the initial vertical shear of the tropical cyclone vortex.

关键词： vortex axisymmetrization asymmetry baroclinicity

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Phase separating Rho:a widespread regulatory function of disordered regions in proteins revealed in bacteria

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Signal Transduction and Targeted Therapy 2023年第7期8卷 3203-3205页

作者： eric Schumbera Pablo Mier Miguel A.Andrade-navarro Institute of Organismic and Molecular Evolution Faculty of BiologyJohannes Gutenberg University of Mainz55128 MainzGermany

A recent study published in Science by Krypotou et *** the role of an intrinsically disordered region(IDR)in the transcription termination Rho protein from Bacteroides thetaiotaomicron:in response to starvation Rho phase separated,which triggered an increase in Rho activity and expression changes.1 These results demonstrate that a highly conserved protein can acquire new regulatory properties in evolution by gaining an IDR that leads to protein phase separation.

关键词： al. disordered separating

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The Coherent-Constructible Correspondence and Fourier-Mukai Transforms

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Acta Mathematica Sinica,English Series 2011年第2期27卷 275-308页

作者： Bohan FAnG Chiu-Chu Melissa LIU David TREUMAnn eric ZASLOW Department of Mathematics Columbia University 2990 Broadway New York NY 10027 USA Department of Mathematics Northwestervt University 2033 Sheridan Road Evanston IL 60208 USA

As evidence for his conjecture in birational log geometry, Kawamata constructed a family of derived equivalences between toric orbifolds. In a previous paper, the authors showed that the derived category of a toric orbifold is naturally identified with a category of polyhedrally-constructible sheaves on R^n. In this paper we investigate and reprove some of Kawamata＇s results from this perspective.

关键词： Toric orbifolds coherent sheaves constructible sheaves Fourier-Mukai transforms

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Effect of Baroclinicity on Vortex Axisymmetrization. Part Ⅰ:Barotropic Basic Vortex

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Advances in Atmospheric Sciences 2014年第6期31卷 1256-1266页

作者： Melinda S.PEnG Jiayi PEnG Tim LI eric HEnDRICKS naval Research Laboratory Monterey California USA IMSG at Environmental Modeling Center NCEP/NOAA College Park Maryland USA Department of Meteorology and IPRC University of Hawaii at Manoa Honolulu Hawaii USA

The barotropic and baroclinic disturbances axisymmetrized by the barotropic basic vortex are examined in an idealized modeling framework consisting of two *** a Wentzel-Kramers-Brillouin approach,the radial propagation of a baroclinic disturbance is shown to be slower than a barotropic disturbance,resulting in a slower linear axisymmetrization for baroclinic *** slower-propagating baroclinic waves also cause more baroclinic asymmetric kinetic energy to be transferred directly to the barotropic symmetric vortex than from barotropic disturbances,resulting in a faster axisymmetrization process in the nonlinear baroclinic wave case than in the nonlinear barotropic wave case.

关键词： vortex axisymmetrization asymmetry baroclinicity

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Enantioconvergent photoredox radical-radical coupling catalyzed by a chiral-at-rhodium complex

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Science China Chemistry 2019年第11期62卷 1512-1518页

作者： Zijun Zhou Xin nie Klaus Harms Radostan Riedel Lilu Zhang eric Meggers Fachbereich Chemie Philipps-Universit?t Marburg

Racemicα-chloro imidazol-2-yl-ketones undergo an enantioconvergent photoactivated C–C bond formation with n-aryl glycines catalyzed by a single bis-cyclometalated chiral-at-rhodium catalyst in yields of up to 80%and up to 98%enantiomeric excess(ee).Control experiments support a mechanism which is initiated by a single electron transfer from n-aryl glycinate to the photochemically excited rhodium-boundα-chloro imidazol-2-yl-ketone,followed by chloride fragmentation of theα-chloroketone,decarboxylation of the glycinate,and a subsequent highly stereocontrolled radical-radical *** work showcases the ability of the chiral rhodium catalyst to serve a dual function as chiral Lewis acid and at the same time as the photoredox active species upon substrate binding.

关键词： photoredox catalysis asymmetric catalysis visible light enantioconvergent radical recombination chiral-at-metal rhodium

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Evaluating Emissions of nitrous Oxide from Cropland Soils Under Different Rotations in Mato Grosso, Brazil:A Scenario Simulation Study

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Pedosphere 2019年第4期29卷 432-443页

作者： Katharina H. E. MEURER eric BOEnECKE Uwe FRAnKO Department of Ecology Swedish University of Agricultural Sciences Uppsala 75007 (Sweden) Department of Soil System Science Helmholtz Center for Environmental Research (UFZ) Halle (Saale) 06120 (Germany)

Expansion of cropland involves immense land use changes, and the resulting intensified management practices have a strong influence on the functioning of the underlying soil. For instance, increased application of nitrogen(n) fertilizer is known to enhance fluxes of nitrous oxide(n2O) from the soil to the atmosphere. The emission factor(EF) proposed by the Intergovernmental Panel on Climate Change(IPCC) assumes a linear relationship between added n and n2O-n fluxes, but it does not account for environmental factors, such as soil properties or climate. Due to the high spatial and temporal variability of n2O-n fluxes, mechanistic models are preferable in terms of extrapolation to larger scales. In this study, we evaluated simulated n2O-n fluxes from soils under agricultural use in the Brazilian state, Mato Grosso, using the CAnDY(Carbon and nitrogen Dynamics) model. A control tool was developed in order to enable the simulation of 1 650 scenarios covering different sites(soil + climate) and management regimes(crop rotation +amount of applied fertilizer + sowing and harvesting dates). Results suggested that the sites had a very strong influence on calculated emissions, which is not accounted for by static EF. Furthermore, most fertilizer-induced n2O-n fluxes derived from the scenario simulations were best described by a non-linear function. For sounder budgeting on the federal and national scale, there is still a strong need for long-term observations of continuous crop rotations and spatial distribution of soil types and their specific characteristics. The presented results provide a valuable starting point for developing further scenario simulations and adapting experimental campaigns for n2O emission study.

关键词： agricultural systems Carbon and nitrogen Dynamics CAnDY model climate emission factor management soil property soil types

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Enantioselective and Enantioconvergent Iron-Catalyzed C(sp^(3))-H Aminations to Chiral 2-Imidazolidinones

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Chinese Journal of Chemistry 2023年第17期41卷 2065-2070页

作者： Tianjiao Cui Chen-Xi Ye Jordan Thelemann Daniel Jenisch eric Meggers Fachbereich Chemie Philipps-Universitat MarburgHans-Meerwein-Strasse 435043MarburgGermany

Comprehensive Summary Enantioselective or enantioconvergent iron-catalyzed ring-closing C(sp^(3))-H aminations of n-aroyloxyurea through intermediate iron nitrene species provide chiral 2-imidazolidinones in up to 99%yield and with up to 95%ee(40 examples).This is a rare example in which sustainable iron catalysis is combined with C(sp^(3))-H amination and asymmetric catalysis.

关键词： Iron Asymmetric catalysis C-H activation Amination nitrenes Heterocycles

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