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Science China(Physics,mechanics & Astronomy) 2004年第2期47卷 146-153页

作者： r. Nicolsky r. de Andrade Jr LASUP-DEE UFRJ Ilha do Fundao Cx.P.68515 21945-970 Rio de Janeiro RJ Brasil Correspondence should be addressed to Yang Wanmin LASUP-DEE UFRJ Ilha do Fundao Cx.P.68515 21945-970 Rio de Janeiro RJ Brasil Correspondence should be addressed to Yang Wanmin

A novel layer deletion method is used to experimentally investigate the effect of induced shielding current transmission (ISCT) in the longitudinal direction on the levitation force of a single-domain YBa2Cu3O7-x (YBCO) cylindrical superconductor (f30? mm). In the experiment the sample was gradually sliced into two equal sheets, at the middle height along a diameter with 5 mm every step. The experimental results show that the levitation force is closely related with the ISCT in the longitudinal direction. Any layer deletion, even a small piece of layer deletion can reduce the levitation force of the sample. After the whole layer was deleted the levitation force can diminish about 50%. It is also found that the levitation force is directly proportional to the effective factor of surface area, which is equal to the top surface area divided by the total surface area parallel to the top surface of the sample.

关键词： melt growth, single domain YBCO, levitation force, induced current distribution.

A review of the dual-wavelength technique for phase imaging and 3D topography

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Light(Advanced manufacturing) 2022年第2期3卷 136-156页

作者： Haowen Zhou mallik m.r.Hussain Partha P.Banerjee Department of Electro-Optics and Photonics University of DaytonDaytonOH 45469USA. Department of Electrical Engineering California Institute of TechnologyPasadenaCA91125USA. Halo Industries Inc. Palo AltoCA95303USA

Optically transmissive and reflective objects may have varying surface profiles,which translate to arbitrary phase profiles for light either transmitted through or reflected from the *** high-throughput applications,resolving arbitrary phases and absolute heights is a key *** extend the ability of measuring absolute phase jumps in existing 3D imaging techniques,the dual-wavelength concept,proposed in late 1800s,has been developed in the last few *** adopting an extra wavelength in measurements,a synthetic wavelength,usually larger than each of the single wavelengths,can be simulated to extract large phases or height variations from micron-level to tens of centimeters *** review a brief history of the developments in the dualwavelength technique and present the methodology of this technique for using the phase difference and/or the phase *** applications of the dual-wavelength technique are discussed,including height feature extraction from micron scale to centimeter scale in holography and interferometry,single-shot dual-wavelength digital holography for high-speed imaging,nanometer height resolution with fringe subdivision method,and applications in other novel phase imaging techniques and optical *** noise sources for dualwavelength techniques for phase imaging and 3D topography are discussed,and potential ways to reduce or remove the noise are mentioned.

关键词： Topography 3D imaging Phase unwrapping Dual wavelength

Virological and molecular Profile of People Living with HIV after 24 Weeks of Treatment with Dolutegravir in Kinshasa

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World Journal of AIDS 2023年第4期13卷 161-170页

作者： Berry I. Bongenya Charlotte Tshinguta Benoit O. Kabengele marie-Thérèse A. S. Sombo Guy m. m. Bumoko mariano m. Lusakibanza Gauthier K. mesia Erick N. Kamangu Faculty of medicine Bel Campus Technological University Kinshasa Democratic Republic of Congo “HIV/AIDS Focus” research Group Kinshasa Democratic Republic of Congo Department of Internal medicine Faculty of Medicine University of Kinshasa Kinshasa Democratic Republic of Congo Department of Neurology Faculty of Medicine University of Kinshasa Kinshasa Democratic Republic of Congo Clinical Pharmacology Unit Department of Pharmacology Faculty of Medicine and Pharmaceutical Sciences University of Kinshasa Kinshasa Democratic Republic of Congo Service of molecular Biochemistry Department of Basic Sciences Faculty of Medicine University of Kinshasa Kinshasa Democratic Republic of Congo

Context: The appointment of the m6 is crucial because it is an indicator of the prognosis of the evolution of the care and the decision-making on the continuation of the AntiretroViral Treatment. Objective: The objective of this study is therefore to present the virological and molecular profile of People Living with HIV under treatment with Dolutegravir 6 months after being put on ArT in Kinshasa. methods: The present study is a cross-sectional view at the sixth month of a prospective cohort to determine the virological and molecular profile of People Living with HIV (PLHIV) after 6 months of ArT based on Dolutegravir (DTG) in Kinshasa. A sample of 5 mL of blood was taken from all HIV patients included. The collection of biological data was carried out under the same conditions as at inclusion. After extraction, Quantitative real-Time PCr was carried out to determine the quantity of HIV rNA in the samples according to the protocols previously described. reverse Transcription PCr (rT-PCr) and Nested PCr were carried out to amplify the regions of interest for Protease and reverse Transcriptase for sequencing. results: The median VL value was 2.92 log10 rNA copies/mL. With 17.75% of patients experiencing major failure of first-line treatment. Subtype A is dominant with 13 cases (20.98%);followed by CrF_02AG (16.13%), subtypes C (14.52%), D (9.68%) and K (6.45%). The K65r (3 cases), T69P/N (6 cases), K70r (9 cases) and m184V (8 cases) mutations were listed as existing mutations for Nucleotide reverse Transcriptase Inhibitors. Conclusion: After 6 months of ArT, 59.67% of People Living with HIV on Tenofovir-Lamivudine-Dolutegravir is in therapeutic success while 40.33% are in a state of treatment failure. Subtype A remains dominant in the population of PLHIV. resistance mutations were detected for Lamivudine and Tenofovir, but none for Dolutegravir.

关键词： Virological Profile molecular PLHIV 6 months of ArT Dolutegravir Kinshasa

Preparation and Properties of Self-reinforced L-and D,L-lactide Copolymer rods

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Chinese Chemical Letters 2000年第11期11卷 1023-1026页

作者： Hu Y.S. Zhang Z.P. Song D. Wang Y.m. Bai D.r. Institute of Polymer Chemistry State Key Lab. Funct. Polymeric M. Nankai University Tianjin 300071 China

Since highly crystalline poly (L-lactide) (PLLA) degrades rather slowly in a biological environment and the crystalline domains remaining after partial degradation of the implant material give rise to an inflammatory response of the surrounding tissue, L- and D,L-lactide copolymer [P(L-DL)LA] having a low crystallinity is preferred in surgical applications. The thermal transitions and the mechanical properties of P(L-DL)LA rods were discussed in this paper. It was found that the self-reinforced P(L-DL)LA [Sr-P(L-DL)LA] was strong enough in terms of mechanical properties compared with the self-reinforced PLLA [Sr-PLLA].

关键词： DL Preparation and Properties of Self-reinforced L-and D,L-lactide Copolymer rods PLLA

Low Grade Appendiceal mucinous Neoplasm Presenting as a mucocoele of the Appendix

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Case reports in Clinical medicine 2022年第9期11卷 380-385页

作者： m. r. Vennila P. Pavan Goud S. Seshasayee S. N. Saravana Sundaram rekha Arcot Saveetha medical College and Hospital Saveetha Institute of Medical and Technical Sciences Tamilnadu India

Low grade appendiceal mucinous neoplasm (LAmN) is a rare malignancy with incidence of 0.7% to 1.7% of all appendicectomies [1]. LAmN has the worst complication of mucin seeding into adjacent peritoneum leading to pseudomyxoma peritonei. LAmN lacks standardised treatment approach where only appendicectomy is preferred for resection of non metastatic disease. Case Presentation A 38 yr old female presented with right lower quadrant where CT Abdomen revealed mucocele of Appendix. Patient underwent Laparoscopic Appendicectomy and Histopathological examination revealed Low grade appendiceal mucinous neoplasm. Patient is on regular follow up and is disease free. Conclusion low grade appendiceal mucinous neoplasm is usually an incidental finding where treatment depends on staging and histology of the tumour.

关键词： Low Grade Appendiceal mucinous Neoplasm Pseudomyxoma Peritonei Appendicectomy

microstructural evolution of mg-14Gd-0.4Zr alloy during compressive creep

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Journal of magnesium and Alloys 2023年第9期11卷 3161-3173页

作者： Hui Shi Yuanding Huang Lixiang Yang Chunquan Liu Hajo Dieringa Chong Lu Lv Xiao regine Willumeit-römer Norbert Hort Institute of metallic Biomaterials Helmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht 21502Germany research and Development Center Shanghai Spaceflight Precision Machinery Research InstituteShanghai 201600China School of mechanical Engineering Guizhou UniversityGuiyang 550025China Institute of material and Process Design Helmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht 21502Germany The Instrument Analysis Center Shanghai Jiaotong UniversityShanghai 200240China Institute of Product Technology and Systems Leuphana University LüneburgUniversitätsallee 1Lüneburg D 21335Germany

The present work reports the creep behavior and microstructural evolution of the sand-cast mg-14Gd-0.4Zr alloy(wt.%) prepared by the differential pressure casting machine. Their compressive creep tests at 250 ℃ were performed under various applied stresses(i.e., 60, 80 and100 mPa). Among them, the sand-cast mg-14Gd-0.4Zr samples examined under 250 ℃/80 mPa for 39 and 95 h, respectively, were chosen to systemically analyze their creep mechanisms using high-angle annular dark field-scanning transmission electron microscopy(HAADF-STEm).The obtained results showed that the enhancement of creep resistance can be mainly attributed to the coherent β' and β'_F phases with an alternate distribution, effectively impeding the basal dislocations movement. However, with the creep time increasing, the fine β'+β'_F precipitate chains coarsened and transformed to semi-coherent β_1 phase and even to large incoherent β phase(surrounded by precipitate-free areas) in grain interiors. The precipitate-free zones(PFZs) at grain boundaries(GBs) were formed, and they could expand during creep deformation. Apart from the main cross-slip of basal and prismatic dislocations, type dislocations were activated and tended to distribute near the GBs. The aforementioned phenomena induced the stress concentrations, consequently leading to the increment of the creep strain.

关键词： magnesium alloys Creep property microstructures Precipitate chains Dislocation

Approximate solutions for the problem of liquid film flow over an unsteady stretching sheet with thermal radiation and magnetic field

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Applied mathematics and mechanics(English Edition) 2018年第6期39卷 867-876页

作者： m.m.KHADEr Department of mathematics and Statistics College of ScienceAl-Imam Mohammad Ibn Saud Islamic University(IMSIU) Department of mathematics Faculty of ScienceBenha University

The proposed method is based on replacement of the unknown function by a truncated series of the shifted Legendre polynomial expansion. An approximate formula of the integer derivative is introduced. Special attention is given to study the convergence analysis and derive an upper bound of the error for the presented approximate formula. The introduced method converts the proposed equation by means of collocation points to a system of algebraic equations with shifted Legendre coefficients. Thus, after solving this system of equations, the shifted Legendre coefficients are obtained. This efficient numerical method is used to solve the system of ordinary differential equations which describe the thin film flow and heat transfer with the effects of the thermal radiation, magnetic field, and slip velocity.

关键词： liquid film thermal radiation unsteady stretching sheet Legendrecollocation method convergence analysis

Suicidal Behaviours in Sickle Cell Patients at the Douala Sickle Cell Care Centre in Cameroon

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Open Journal of Psychiatry 2024年第3期14卷 265-281页

作者： Christian Eyoum Léonce Kengno Kologne Charlotte Eposse Ekoube Annick mélanie magnerou Joséphine manga Befolo Cindy Laura Ndepa Daniel Gams massi Aurore Nzesseu Djomo Guy Jonas Basseguin Atchou Guy Calvin mbongo’O rihta mbono mbekoto Iyawa Hassanatou Fabiola Tchouankeu Kounga Christiane medi Sike Josiane Essola Jacques Narcisse Doumbe Erero Njiengwe Callixte Kuate Tegueu Faculty of medicine and Pharmaceutical Sciences University of Douala Douala Cameroon Laquintinie Hospital Douala Cameroon Faculty of Health Sciences University of Buea Buea Cameroon Faculty of medicine and Biomedical Sciences University of Yaound&#233 1 Yaound&#233 Cameroon

Introduction: Sickle cell anaemia is a hereditary disease that combines physical and psychological manifestations, including suicidal tendencies. So far, to our knowledge, no study has been conducted on suicidal behaviours among people with sickle cell disease in Cameroon. This is what justifies our study on the prevalence and factors related to suicidal behaviors in our study population. methods: We conducted a cross-sectional, analytical study of 171 sickle cell patients aged from 12 years upwards who came to the sickle cell disease care service of the Laquintinie Hospital in Douala, over a period of 6 months, that is, from 1 January to 31 June 2022. Data were collected using a structured questionnaire with questions on suicidal behaviours based on the “mINI” (mini International Neuropsychiatric Interview). The data were processed using the SPSS 26.0 software. The related factors were studied in both a bivariate and multivariate analysis. results: Female sickle cell patients accounted for 60.2% of the sample. The mean age was 23.36 ± 8.42 years. Suicidal ideation was prevalent in 56% of cases and 13% attempted suicide. The factors most associated with suicidal ideation were: primary level of education (Or = 0.08 (0.09 - 0.79);p = 0.03), feeling unworthy of life (Or = 0.40 (0.08 - 1.96);p = 0.02), not often being considered by those around them (Or = 2.97 (1.26 - 6.99);p = 0.01), lack of family support (Or = 0.34 (0.15 - 0.77);p = 0.01). meanwhile, the factors associated with suicide attempts were: the fact of being rarely exposed to suicide-related media (Or = 4.17 (1.40 - 71.80);p = 0.03), and a constant feeling of sadness when returning home (Or = 18.02 (1.59 - 20.55);p = 0.01). Conclusion: more than half of sickle cell patients had had suicidal thoughts and 1/6 had made at least one suicide attempt, women and young adults being the most concerned. It is therefore necessary to ensure optimum psychological care for patients with sickle cell disease.

关键词： Sickle Cell Disease Suicidal Behaviours Self-Harm

The development of a high-performance Ni-superalloy additively manufactured heat pipe

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Advances in manufacturing 2022年第4期10卷 610-624页

作者： Sheng Li Khamis Essa James Carr States Chiwanga Andrew Norton moataz m.Attallah School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006People’s Republic of China School of Engineering University of BirminghamEdgbastonBirmingham B152TTUK Henry moseley X-ray Imaging Facility Henry Royce Institute for Advanced MaterialsDepartment of MaterialsUniversity of ManchesterManchester M139PLUK European Thermodynamics Ltd 8 Priory Business ParkWistow RoadKibworthLeicestershire LE80RXUK rolls-royce plc P.O.Box 31Derby DE248BJUK School of metallurgy and materials University of BirminghamEdgbastonBirmingham B152TTUK

Additively manufacturing(Am)has been used to manufacture fine structures with structured/engineered porosity in heat management *** this study,laser powder bed fusion(LPBF)was used to manufacture a high-performance Ni-superalloy heat pipe,through tailoring LPBF process parameters to fabricate thin wall and *** using novel laser scanning strategies,wick structure heat pipes with maximised surface-area-to-volume ratio,fine features size around 100µm,and controlled porosity were successfully *** and X-ray microtomography(micro-CT)were used to investigate the 3D structure of the void space within the *** test results showed that most of the heat pipes made by LPBF had better performance than the conventionally manufactured *** study also investigated the influences of the process parameters on the porosity volume fraction and the feature *** results showed that LPBF process could fabricate thin structure due to the change of melt pool contact *** relationship between process parameters and bead size reported in this study could help design and manufacture heat pipe with complex fine structure.

关键词： Laser powder bed fusion(LPBF) Heat pipe melt pool microtomography(micro-CT)

regression analysis and features of negative activation energy for mHD nanofluid flow model:A comparative study

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Propulsion and Power research 2023年第2期12卷 273-283页

作者： B.Kumara Prachi Abhinav Singhal r.Nandkeolyar Pulkit Kumar Ali J.Chamkha School of mathematics Thapar Institute of Engineering and TechnologyPatiala 147004PunjabIndia Department of Applied Sciences and Humanities RITRoorkee 247667India School of Sciences Christ(Deemed to be University)Delhi NCR 201003India Department of mathematics National Institute of TechnologyJamshedpur 831014India Department of Applied mechanics Indian Institute of TechnologyDelhi 110016India Faculty of Engineering Kuwait College of Science and TechnologyDoha DistrictKuwait

This article elucidates the impact of activation energy on magnetohydrodynamic(mHD)stagnation point nanofluid flow over a slippery surface in a porous regime with thermophoretic and Brownian *** activation energy is scarce in practice,but the impact of negative activation energy could not be neglected as it is noticed in chemical *** rate of some Arrhenius-compliant reactions is retarded by increasing the temperature and is therefore associated with negative activation energies,such as exothermic binding of urea or *** some processes,the temperature dependence of the pressure-induced unfolding and the urea-induced unfolding of proteins at ambient pressure give negative activation *** present mathematical model is solved with successive linearization method(a spectral technique).A comparison of results is made for negative and positive values of activation *** from it,the quadratic multiple regression model is discussed briefly and explained with bar *** is observed that with rise in unsteadiness parameter from 0 to 1(taking positive activation energy),skin friction and Sherwood number are increased by 9.36%and 19%respectively,and Nusselt number is decreased by 26%.However,for negative activation energy,9.36%and 112%enhancement is observed in skin friction and Sherwood number,respectively.

关键词： Negative activation energy regression analysis Successive linearization method Porous medium