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Discontinuation of therapy in inflammatory bowel disease: Current views

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World Journal of Clinical Cases 2024年第10期12卷 1718-1727页

作者： Antonio meštrović Marko Kumric Josko Bozic Department of Gastroenterology University Hospital of SplitSplit 21000Croatia Department of Pathophysiology University of Split School of MedicineSplit 21000Croatia

The timely introduction and adjustment of the appropriate drug in accordance with previously well-defined treatment goals is the foundation of the approach in the treatment of inflammatory bowel disease(IBD).The therapeutic approach is still evolving in terms of the mechanism of action but also in terms of the possibility of maintaining *** patients with achieved long-term remission,the question of de-escalation or discontinuation of therapy arises,considering the possible side effects and economic burden of long-term *** each of the drugs used in IBD(5-aminosalycaltes,immunomodulators,biological drugs,small molecules)there is a risk of ***,studies show that more than 50%of patients who discontinue therapy will *** on the findings of large studies and meta-analysis,relapse of disease can be expected in about half of the patients after therapy withdrawal,in case of monotherapy with aminosalicylates,immunomodulators or biological ***,longer relapse-free periods are recorded with withdrawal of medication in patients who had previously been on combination therapies immunomodulators and anti-tumor necrosis *** needs to be stressed that randomised clinical trials regarding withdrawal from medications are still *** making a decision on discontinuation of therapy,it is important to distinguish potential candidates and predictive factors for the possibility of disease *** calprotectin level has currently been identified as the strongest predictive factor for *** other predictive factors have also been identified,such as:High Crohn's disease activity index or Harvey Bradshaw index,younger age(40 years),smoking,young age of disease onset,steroid use 6-12 months before *** important factor in the decision to withdraw medication is the success of re-treatment with the same or other *** decision to discontinue therapy must be based on in

关键词： Inflammatory bowel disease Therapy discontinuation Therapy de-escalation Ulcerative colitis Crohn’s disease

Analysis of mid-spatial frequency wavefront distortions from a liquid-cooled flash-lamp pumped Nd:phosphate laser amplifier

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High Power Laser Science and Engineering 2024年第1期12卷 24-29页

作者： Pierre-Marie Dalbies Sandy Cavaro Edouard Bordenave Nathalie Blanchot Julien G.Moreau Jérôme Neauport CEA CESTA Le BarpFrance

Mid-spatial frequency wavefront deformation can be deleterious for the operation of high-energy laser systems. When fluid cooled high-repetition-rate amplifiers are used, the coolant flow is likely to induce such detrimental mid-spatial frequency wavefront deformations. Here, we describe the design and performance of a 90 mm × 90 mm aperture, liquid-cooled Nd:phosphate split-slab laser amplifier pumped by flash-lamps. The performance of the system is evaluated in terms of wavefront aberration and gain at repetition rates down to 1 shot per minute. The results show that this single cooled split-slab system exhibits low wavefront distortions in the medium to large period range, compatible with a focus on target, and despite the use of liquid coolant traversed by both pump and amplified wavelengths. This makes it a potential candidate for applications in large high-energy laser facilities.

关键词： flash-lamp pumping high-power laser laser cooling neodymium glass wavefront error

Lax-Oleinik-Type Formulas and Efficient Algorithms for Certain High-Dimensional Optimal Control Problems

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1428-1471页

作者： Paula Chen Jerome Darbon Tingwei meng Division of Applied Mathematics Brown UniversityProvidenceRIUSA Department of Mathematics UCLALos AngelesCAUSA

Two of the main challenges in optimal control are solving problems with state-dependent running costs and developing efficient numerical solvers that are computationally tractable in high *** this paper,we provide analytical solutions to certain optimal control problems whose running cost depends on the state variable and with constraints on the *** also provide Lax-Oleinik-type representation formulas for the corresponding Hamilton-Jacobi partial differential equations with state-dependent ***,we present an efficient,grid-free numerical solver based on our representation formulas,which is shown to scale linearly with the state dimension,and thus,to overcome the curse of *** existing optimization methods and the min-plus technique,we extend our numerical solvers to address more general classes of convex and nonconvex initial *** demonstrate the capabilities of our numerical solvers using implementations on a central processing unit(CPU)and a field-programmable gate array(FPGA).In several cases,our FPGA implementation obtains over a 10 times speedup compared to the CPU,which demonstrates the promising performance boosts FPGAs can *** numerical results show that our solvers have the potential to serve as a building block for solving broader classes of high-dimensional optimal control problems in real-time.

关键词： Optimal control Hamilton-Jacobi partial differential equations Grid-free numerical methods High dimensions Field-programmable gate arrays(FPGAs)

Dynamic Modelling of a Hybrid Variable Reluctance Machine Using the 3D Finite Element method

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Journal of Electromagnetic Analysis and Applications 2024年第7期16卷 103-113页

作者： Dingamadji Hilaire Belemdara Jérôme Mbaïnaïbeye Department of Physics and Engineering Sciences University of NDjamena NDjamena Chad Department of Physics University of Moundou Moundou Chad

This paper presents the work carried out to evaluate the dynamic performance of the Hybrid Variable Reluctance Motor (HVRM). The fourth-order Runge-Kutta integration algorithm was employed to solve the equations of the dynamic model, in conjunction with the three-dimensional finite element method. The 3D numerical data was calculated using Comsol Multiphysics, which accounts for the nonlinearity of the ferromagnetic material and the 3D nature of the HVRM. The outcomes of this study are precise and accurately predict the dynamic behaviour of the HVRM in terms of rotor position response, rotational speed and torque. The distinctive contribution of this work lies in the 3D numerical modelling of the HVRM and the subsequent evaluation and analysis of its dynamic operation. Analytical and numerical 2D studies are less resource-intensive and time-consuming, and are more straightforward and rapid to analyse and interpret. However, they are constrained in their capacity to examine spatial, volumetric interactions and intricate dynamics such as flux studies where three 3D effects cannot be disregarded, winding end effects and the configuration and positioning of the interposed permanent magnet.

关键词： Numerical Computing Complex Dynamic Flux Linkage 3D Effects Equilibrium Position

Contribution to the Full 3D Finite Element Modelling of a Hybrid Stepping Motor with and without Current in the Coils

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Journal of Electromagnetic Analysis and Applications 2024年第2期16卷 11-23页

作者： Belemdara Dingamadji Hilaire Mbaïnaïbeye Jérôme Guidkaya Golam Department of Physics and Engineering Sciences University of N&#8217Djamena N&#8217Djamena Chad Department of Physics University of Moundou Moundou Chad Department of Physics University of Ngaoundere Ngaoundere Cameroon

The paper presents our contribution to the full 3D finite element modelling of a hybrid stepping motor using COMSOL Multiphysics software. This type of four-phase motor has a permanent magnet interposed between the two identical and coaxial half stators. The calculation of the field with or without current in the windings (respectively with or without permanent magnet) is done using a mixed formulation with strong coupling. In addition, the local high saturation of the ferromagnetic material and the radial and axial components of the magnetic flux are taken into account. The results obtained make it possible to clearly observe, as a function of the intensity of the bus current or the remanent induction, the saturation zones, the lines, the orientations and the magnetic flux densities. 3D finite element modelling provide more accurate numerical data on the magnetic field through multiphysics analysis. This analysis considers the actual operating conditions and leads to the design of an optimized machine structure, with or without current in the windings and/or permanent magnet.

关键词： Modelling 3D Finite Elements Magnetic Flux Hybrid Stepping Motor

Ovarian Tumors in Senegalese Women: Impact of D-Loop Mutations between Healthy and Cancerous Tissues

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Open Journal of Genetics 2024年第2期14卷 37-46页

作者： Rouguiyatou Ka Fatimata Mbaye Bineta Kénéme Mbacké Sembène Genomics Laboratory Department of Animal Biology Faculty of Science and Technology Cheikh Anta Diop University Dakar Senegal

In Senegal in particular, ovarian cancer, which is one of the most common gynecological cancers, accounts for 2.8% of deaths. The most important risk factor is genetic, with 10% of cases occurring in a context of genetic predisposition. The sequencing of the human genome, which has led to the discovery of millions of sequence variations, makes it possible to study variations within sequences. These variations are limited to Single Nucleotide Polymorphisms (SNPs) and this common form of polymorphism occurs approximately every 1000 bases in the human genome and 1.8 million SNPs are currently listed according to [1]. The aim of this study is to gain a better understanding of the impact of mutations in the D-loop region of mtDNA on ovarian cancer in Senegalese women. This study involved searching for mutations in our study population after DNA extraction and sequencing. Mutations were found after a comparison of our sequences with the Cambridge reference sequence (NC_012920). The mutations found in the DNA studied extend from position 7 to position 16568 and most of these mutations are located in the hypervariate zones (HV1 and HV2). Heteroplasmy with three mutant alleles was also found in certain variants. Common mutations were found in both healthy and cancerous tissues, with almost identical frequencies in both types of tissue. This enabled us to understand the spread of tumor cells throughout the ovary.

关键词： Ovarian Cancer Mutations D-Loop Heteroplasmy

Flow Dynamics during the Hydrocarbon Exploitation for Prevention and Management of Water Venues in Oil Field: A Study Case of Crystal Field in Badila/Chad

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International Journal of Geosciences 2024年第5期15卷 433-448页

作者： Issakha Tidjani Djimet Huguette Christiane Emvoutou Nicodème Djiedeu Jean-Pierre Nguenang Laboratory of Fundamental Physics Department of Physics Faculty of Science University of Douala Douala Cameroon Laboratory of Geosciences Natural Resources and Environment Department of Earth Sciences Faculty of Science University of Douala Cameroon

The southern part of the Lake Chad basin is under the gas and oil petroleum industry due to its hydrocarbon potential for about twenty years. This project stands out as the main challenges of the hydrocarbon production and the management of fluxes particularly the groundwater venues. A comprehensive study is thus conducted to develop a dynamic and analytic model for diagnosing the production performances with a particular view on the management of groundwater venues. The three main concerned reservoirs subdivided on subunits evidence their proper characteristics. The porous media, their densities, the internal flows and the water injection techniques such as water flooding were thus adopted. The oil viscosity variability within the reservoirs creates different levels of mobility between water and oil, highlighting the challenges of water management. The material balance model and the behavior of the well analysis were taken in consideration within the identified aquifer, emphasizing the importance of keeping the pressure through injection. The control of water productions, the management of the reservoir, the well strategical position and the specific completions lead to the model functioning. In addition, the CO log and the Pulsed Neutron indicate their limitations as a result of the water salinity and the porosity of the aquifer. The management of groundwater venues at Badila requires various approaches throughout the lifetime of the Crystal field such as the data acquisition and remediation actions and prevention, under a permanent monitoring of the dynamic fluxes in the reservoirs.

关键词： Groundwater Venues Analytic and Dynamic Model Water Flooding Optimization of Production

Prevalence and Factors Associated with Positivity of Antinuclear Antibodies (ANA) Patterns, Native Anti-DNA and Extractable Nuclear Antigens (ENA) Antibodies: Experience from a Laboratory in Dakar

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Open Journal of Rheumatology and Autoimmune Diseases 2024年第1期14卷 26-36页

作者： Diop Abdou Diallo Thierno Abdoulaye Ndiaye Babacar Mahou Chantal Diop Marième Gaye Dubrous Phillippe Seck Abdoulaye medical Biology Laboratory Pasteur Institute of Dakar Dakar Senegal Cheikh Anta Diop University of Dakar Dakar Senegal

Background: Diagnosis of autoimmune diseases (AID) is challenging, due to overlapping features with other non-immune disorders. Anti-nuclear antibodies (ANA) are sensitive screening tests but anti-deoxyribonucleic acid-antibody (anti-DNA), and anti-extractable nuclear antigens (anti-ENA) are specific for AIDs. We aimed to look at ANA patterns in our patients and correlated them with anti-ENA for proper interpretation and better patient management cost-effectively. methods: A retrospective study was conducted over 1 year from January to December 2022 who were tested for ANA at biology medical laboratory of Pasteur Institute of Dakar. Anti-ENA and anti-DNA results were also analyzed for ANA-positive patients. Statistical analysis was performed using STATA 14.0, p Results: 216 patients were analyzed. Women predominated at 79.2% and mean age was 48 years [CI 95%, 46 - 50], with extremes of 10 and 89. Most represented age group was [41 - 60] with 38%. ANA was positive in 27 (12.5%) of patients, 59.2% of whom were strongly positive (titer of 1/1000, 1/3200 or 1/6400). The most common pattern was nuclear speckled, which was found in 77.8% of samples. Anti-ENA and anti-DNA positivity in ANA-positive patients was found respectively in 63% (17/27) and 1.4% (3/27) of the samples analyzed. Most commonly identified anti-ENA was anti-Sm 29.6%, anti-SSA 29.6%, anti-Ro-52 25.9%, anti-RNP 18.5% and anti-SSB 14.8% which was associated with speckled pattern. Association results indicated a significant relationship between both tests and between ANA titer in the anti-ENA- and ANA-positive patients (p 0.001). Conclusions: ANA, Anti-ENA and anti-DNA antibodies are essential for AIDS diagnosis. However, the testing repertoire should follow an algorithm comprising of clinical features, followed by ANA results with nuclear, mitotic, and cytoplasmic patterns, anti-ENA, and anti-DNA for a more meaningful, and cost-effective diagnostic approach.

关键词： Antinuclear Antibodies Extractable Nuclear antigen Autoimmune Disease Indirect Immunofluorescence

New Approach to Rock Classification Based on Sparse Representations

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Open Journal of Applied Sciences 2024年第1期14卷 145-158页

作者： Wognin Joseph Vangah Bi G. Théodore Toa Alico Nango Jerôme Ouattara Sie Alain Clément Unité de Recherche et d’expertise Numérique (UREN) Université Virtuelle de C&#244te d’Ivoire (UVCI) Abidjan C&#244te d’Ivoire UFR Sciences et technologique Département de Physique Université polytechnique de Man (UPM) Man C&#244te d’Ivoire Classe Préparatoire des Grandes Ecoles (CPGE) Université de San Pédro (USP) San Pédro C&#244te d’Ivoire Institut National Polytechnique Houphouë t (INPHB) Yamoussoukro C&#244te d’Ivoire Laboratoire Angevin de Recherche en Ingénierie des Systèmes (LARIS) Institut Universitaire de Technologie (IUT) Université d’Angers Angers France

In geology, classification and lithological recognition of rocks plays an important role in the area of oil and gas exploration, mineral exploration and geological analysis. In other fields of activity such as construction and decoration, this classification makes sense and fully plays its role. However, this classification is slow, approximate and subjective. Automatic classification curbs this subjectivity and fills this gap by offering methods that reflect human perception. We propose a new approach to rock classification based on direct-view images of rocks. The aim is to take advantage of feature extraction methods to estimate a rock dictionary. In this work, we have developed a classification method obtained by concatenating four (4) K-SVD variants into a single signature. This method is based on the K-SVD algorithm combined with four (4) feature extraction techniques: DCT, Gabor filters, D-ALBPCSF and G-ALBPCSF, resulting in the four (4) variants named K-Gabor, K-DCT, KD-ALBPCSF and KD-ALBPCSF respectively. In this work, we developed a classification method obtained by concatenating four (4) variants of K-SVD. The performance of our method was evaluated on the basis of performance indicators such as accuracy with other 96% success rate.

关键词： Rock Recognition Dictionary Signature Color Texture K-SVD Variants KD-ALBPCSF Et KG-ALBPCSF