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Unsteady MHD Casson Nanofluid Flow Past an Exponentially Accelerated Vertical Plate:An Analytical Strategy
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作者 T.Aghalya R.Tamizharasi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期431-460,共30页
In this study,the characteristics of heat transfer on an unsteady magnetohydrodynamic(MHD)Casson nanofluid over an exponentially accelerated vertical porous plate with rotating effects were investigated.The flow was d... In this study,the characteristics of heat transfer on an unsteady magnetohydrodynamic(MHD)Casson nanofluid over an exponentially accelerated vertical porous plate with rotating effects were investigated.The flow was driven by the combined effects of the magnetic field,heat radiation,heat source/sink and chemical reaction.Copper oxide(CuO)and titanium oxide(TiO2)are acknowledged as nanoparticle materials.The nondimensional governing equations were subjected to the Laplace transformation technique to derive closed-form solutions.Graphical representations are provided to analyze how changes in physical parameters,such as the magnetic field,heat radiation,heat source/sink and chemical reaction,affect the velocity,temperature and concentration profiles.The computed values of skin friction,heat and mass transfer rates at the surface were tabulated for various sets of input parameters.It is perceived that there is a drop in temperature due to the rise in the heat source/sink and the Prandtl number.It should be noted that a boost in the thermal radiation parameter prompts an increase in temperature.An increase in the Prandtl number,heat source/sink parameter,time and a decrease in the thermal radiation parameter result in an increase in theNusselt number.The computed values of the skin friction,heat andmass transfer rates at the surface were tabulated for various values of the flow parameters.The present results were compared with those of previously published studies andwere found to be in excellent agreement.This research has practical applications in areas such as drug delivery,thermal medicine and cancer treatment. 展开更多
关键词 Thermal radiation radiative flux NANOFLUID copper oxide titanium oxide accelerated plate
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Clinical Practice of Evidence-Based PDCA Cycle Management Model in Accelerated Recovery of Lung Cancer Patients
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作者 Lu Kang Juan Yuan +1 位作者 Dandan Liu Bo Deng 《Journal of Cancer Therapy》 2024年第4期130-140,共11页
Objective: To explore the nursing effect of evidence-based PDCA cycle management mode in accelerated rehabilitation of patients undergoing thoracoscopic lung cancer radical surgery. Methods: 104 patients who underwent... Objective: To explore the nursing effect of evidence-based PDCA cycle management mode in accelerated rehabilitation of patients undergoing thoracoscopic lung cancer radical surgery. Methods: 104 patients who underwent thoracoscopic lung cancer radical surgery in our hospital from June 2022 to February 2023 were randomly divided into control group and intervention group, with 52 cases in each group. The control group implemented evidence-based ERAS clinical pathway management, while the intervention group implemented evidence-based PDCA cycle quality management. The postoperative recovery of the two groups of patients was compared. Results: The postoperative recovery of the intervention group was significantly better than that of the control group. The first time to get out of bed, the first time to eat, the duration of chest drainage tube placement, and the length of hospital stay were significantly shorter than those of the control group. The incidence of postoperative chest complications and hospitalization costs were significantly lower than those of the control group, and patient satisfaction was significantly higher than that of the control group (P Conclusion: Evidence-based PDCA cycle quality management mode can effectively improve the implementation quality of accelerated rehabilitation nursing for patients undergoing thoracoscopic lung cancer radical surgery, and it is worthy of clinical promotion. 展开更多
关键词 EVIDENCE-BASED PDCA Cycle Thoracoscopic Lung Cancer Radical Surgery accelerated Rehabilitation
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Accelerated Primal-Dual Projection Neurodynamic Approach With Time Scaling for Linear and Set Constrained Convex Optimization Problems
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作者 You Zhao Xing He +1 位作者 Mingliang Zhou Tingwen Huang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1485-1498,共14页
The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence rates.Most previous studies in this field have primarily concentrated on... The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence rates.Most previous studies in this field have primarily concentrated on unconstrained smooth con-vex optimization problems.In this paper,on the basis of primal-dual dynamical approach,Nesterov accelerated dynamical approach,projection operator and directional gradient,we present two accelerated primal-dual projection neurodynamic approaches with time scaling to address convex optimization problems with smooth and nonsmooth objective functions subject to linear and set constraints,which consist of a second-order ODE(ordinary differential equation)or differential conclusion system for the primal variables and a first-order ODE for the dual vari-ables.By satisfying specific conditions for time scaling,we demonstrate that the proposed approaches have a faster conver-gence rate.This only requires assuming convexity of the objective function.We validate the effectiveness of our proposed two accel-erated primal-dual projection neurodynamic approaches through numerical experiments. 展开更多
关键词 accelerated projection neurodynamic approach lin-ear and set constraints projection operators smooth and nonsmooth convex optimization time scaling.
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Almost Sure Convergence of Proximal Stochastic Accelerated Gradient Methods
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作者 Xin Xiang Haoming Xia 《Journal of Applied Mathematics and Physics》 2024年第4期1321-1336,共16页
Proximal gradient descent and its accelerated version are resultful methods for solving the sum of smooth and non-smooth problems. When the smooth function can be represented as a sum of multiple functions, the stocha... Proximal gradient descent and its accelerated version are resultful methods for solving the sum of smooth and non-smooth problems. When the smooth function can be represented as a sum of multiple functions, the stochastic proximal gradient method performs well. However, research on its accelerated version remains unclear. This paper proposes a proximal stochastic accelerated gradient (PSAG) method to address problems involving a combination of smooth and non-smooth components, where the smooth part corresponds to the average of multiple block sums. Simultaneously, most of convergence analyses hold in expectation. To this end, under some mind conditions, we present an almost sure convergence of unbiased gradient estimation in the non-smooth setting. Moreover, we establish that the minimum of the squared gradient mapping norm arbitrarily converges to zero with probability one. 展开更多
关键词 Proximal Stochastic accelerated Method Almost Sure Convergence Composite Optimization Non-Smooth Optimization Stochastic Optimization accelerated Gradient Method
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The Accelerated Expansion of the Universe in the Light of the Maximum Ordinality Principle
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2024年第2期585-602,共18页
The main aim of the paper is to present (and at the same time offer) a differ-ent perspective for the analysis of the accelerated expansion of the Universe. A perspective that can surely be considered as being “in pa... The main aim of the paper is to present (and at the same time offer) a differ-ent perspective for the analysis of the accelerated expansion of the Universe. A perspective that can surely be considered as being “in parallel” to the tradition-al ones, such as those based, for example, on the hypotheses of “Dark Matter” and “Dark Energy”, or better as a “com-possible” perspective, because it is not understood as being “exclusive”. In fact, it is an approach that, when con-firmed by experimental results, always keeps its validity from an “operative” point of view. This is because, in analogy to the traditional perspectives, on the basis of Popper’s Falsification Principle the corresponding “Generative” Logic on which it is based has not the property of the perfect induction. The basic difference then only consists in the fact that the Evolution of the Universe is now modeled by considering the Universe as a Self-Organizing System, which is thus analyzed in the light of the Maximum Ordinality Principle. 展开更多
关键词 accelerated Expansion of the Universe Maximum Ordinality Principle Incip-ient Differential Calculus
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Clinical outcomes at one year following keratoconus treatment with accelerated transepithelial cross-linking
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作者 Alberto Artola 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第4期652-655,共4页
This study evaluated the clinical outcomes in keratoconus corneas following accelerated transepithelial corneal collagen cross-linking(CXL)(Avedro KXL system,Waltham,MA,USA) over one year of follow-up.The mean de... This study evaluated the clinical outcomes in keratoconus corneas following accelerated transepithelial corneal collagen cross-linking(CXL)(Avedro KXL system,Waltham,MA,USA) over one year of follow-up.The mean depth of the demarcation line measured by optical coherence tomography(OCT) was 205.19 μm.One month after surgery,a non-statistically significant change was noted in sphere(P= 0.18) and in spherical equivalent(P= 0.17),whereas a significant improvement was observed in corrected distance visual acuity(P=0.04).A significant change was observed in topographic astigmatism(P= 0.03) and posterior corneal a sphericity(P= 0.04).Accelerated transepithelial CXL may be a useful technique for the management of progressive keratoconus. 展开更多
关键词 comeal collagen cross-linking KERATOCONUS transepithelial cross-linking accelerated transepithelial cross-linking corneal ectasia
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Cross-linking density and aging constitutive model of HTPB coating under prestrain thermal accelerated aging
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作者 Yong-qiang Du Jian Zheng Chao Xiong 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第2期439-446,共8页
In order to study the cross-linking density and aging constitutive relationship of HTPB coating during storage,the thermal accelerated aging tests at 0%,3%,6%and 9%prestrains were carried out.The crosslinking density ... In order to study the cross-linking density and aging constitutive relationship of HTPB coating during storage,the thermal accelerated aging tests at 0%,3%,6%and 9%prestrains were carried out.The crosslinking density of HTPB coating at different aging stages were tested using low-field^1 H NMR and the variation of cross-linking density was analyzed.The aging model of cross-linking density considering the chemical aging and the physical stretching factors was established.The uniaxial tensile tests were carried out on HTPB coating at different aging stages and the cross-linking density was introduced into Ogden hyperelastic constitutive model as a characterization parameter of correction coefficient.Combined with uniaxial tensile test results,a prestrain aging constitutive model of HTPB coating was established.The results show that the cross-linking density of HTPB coating increases rapidly at first and then slowly with the increase of thermal accelerated aging time without prestrain.Under prestrain conditions,the crosslinking density of HTPB coating decreases at the early stage,and increases rapidly at first and then slowly at the middle and late stages of thermal accelerated aging.The correlation coefficients of aging model of cross-linking density and aging constitutive model with test results are R>0.9500 and R>0.9900 respectively,which can be used to accurately describe the cross-linking density and aging constitutive relationship of HTPB coating under prestrain accelerated thermal aging conditions. 展开更多
关键词 PRESTRAIN THERMAL accelerated AGING Low-field^1H NMR cross-linking density AGING CONSTITUTIVE model
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Trans-epithelial accelerated corneal cross-linking for keratoconus in children
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作者 Andrew Olivo-Payne Juan Carlos Serna-Ojeda +6 位作者 Erick Hernandez-Bogantes Alexandra Abdala-Figuerola Lueero Pedro-Aguilar Alejandro Liehtinger Arturo Ramirez-Miranda Alejandro Navas Enrique O. Graue-Hernandez 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第12期1919-1921,共3页
The aim of the study is to evaluate the safety and effi cacy of trans-epithelial accelerated corneal cross-linking(TE-ACXL) in children with progressive keratoconus.Retrospective,case-series of 23 eyes of 14 childre... The aim of the study is to evaluate the safety and effi cacy of trans-epithelial accelerated corneal cross-linking(TE-ACXL) in children with progressive keratoconus.Retrospective,case-series of 23 eyes of 14 children who underwent TE-ACXL.Evaluations were performed at baseline and 1,3,6,12 and 18 mo postoperatively.Mean follow-up time of 23.82±3.15 mo and mean age was 13.7±1.4 y(range 11 to 16 y).Mean preoperative uncorrected distance visual acuity changed from 0.92±0.45 log MAR(20/160) to 0.71±0.40 log MAR(20/100)(P=0.001).Mean keratometry(Km) changed from 53.87± 6.03 to 53.00±5.81(P=0.001).Pachymetry did not have significant changes at last follow-up(P=0.30).The mean preoperative sphere was-5.58±2.48 and-4.89±4.66 D(P=0.11) at last follow-up;refractive cylinder from-5.58±2.48 to-5.02±2.23(P=0.046).In conclusion,tomographic and refractive stability are shown in over 91% of eyes with pediatric progressive keratoconus who underwent TE-ACXL. 展开更多
关键词 corneal cross-linking KERATOCONUS acceleratedcross-linking pediatric keratoconus
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Subclinical inflammatory response after accelerated corneal cross-linking
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作者 Hassan Hashemi Nahid Ashraf +2 位作者 Ebrahim Jafarzadehpur Alireza Hedayatfar Soheila Asgari 《Eye Science》 CAS 2016年第2期107-110,共4页
Background:To evaluate the inflammatory response after accelerated collagen cross-linking(CXL)in eyes with keratoconus.Methods:Consecutive eyes with keratoconus undergoing CXL surgery were included in this nonrandomiz... Background:To evaluate the inflammatory response after accelerated collagen cross-linking(CXL)in eyes with keratoconus.Methods:Consecutive eyes with keratoconus undergoing CXL surgery were included in this nonrandomized interventional study.Aqueous flare was measured pre-and post-operatively with a laser flare photometer at 1 week,1,3 and 6 months after CXL.Results:Sixty eyes of 60 patients were entered into the study.Before CXL,the mean flare value was4.5 photons per millisecond(ph/ms).The flare values observed at week 1(7.1 ph/ms;P=0.008),month 1(6.5 ph/ms;P=0.04),month 3(6.7 ph/ms;P=0.004)and month 6(6.7 ph/ms;P=0.004)were significantly higher compared to baseline.Flare values were not significantly different from week 1 up to 6 months after CXL(P=0.930).No statistically significant correlation was detected between the amount of inflammation and keratometric indices.Conclusions:Accelerated CXL in patients with keratoconus may cause a subclinical inflammatory response which is evident as slight but rather long-lasting rise of aqueous flare. 展开更多
关键词 炎症反应 角膜 临床 交联 火焰光度计 pH值 相关性检测 毫秒
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Construction of all-organic low dielectric polyimide hybrids via synergistic effect between covalent organic framework and cross-linking structure 被引量:1
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作者 Wanjing Zhao Zhaoyang Wei +6 位作者 Chonghao Lu Yizhang Tong Jingshu Huang Xianwu Cao Dean Shi Robert KYLi Wei Wu 《Nano Materials Science》 EI CAS CSCD 2023年第4期429-438,共10页
Polyimide(PI)is a promising electronic packaging material,but it remains challenging to obtain an all-organic PI hybrid film with decreased dielectric constant and loss without modifying the monomer.Herein,a series of... Polyimide(PI)is a promising electronic packaging material,but it remains challenging to obtain an all-organic PI hybrid film with decreased dielectric constant and loss without modifying the monomer.Herein,a series of allorganic PI hybrid films were successfully prepared by introducing the covalent organic framework(COF),which could induce the formation of the cross-linking structure in the PI matrix.Due to the synergistic effects of the COF fillers and the cross-linking structure,the PI/COF hybrid film containing 2 wt%COF exhibited the lowest dielectric constant of 2.72 and the lowest dielectric loss(tanδ)of 0.0077 at 1 MHz.It is attributed to the intrinsic low dielectric constant of COF and a large number of mesopores within the PI.Besides,the cross-linking network of PI prevents the molecular chains from stacking and improves the fraction of free volume(FFV).The molecular dynamics simulation results are well consistent with the dielectric properties data.Furthermore,the PI/COF hybrid film with 5 wt%COF showed a significant enhancement in breakdown strength,which increased to 412.8 kV/mm as compared with pure PI.In addition,the PI/COF hybrid film achieve to reduce the dielectric constant and thermal expansion coefficient(CTE).It also exhibited excellent thermal,hydrophobicity,and mechanical performance.The all-organic PI/COF hybrid films have great commercial potential as next-generation electronic packaging materials. 展开更多
关键词 POLYIMIDE Covalent organic framework All-organic cross-linking structure Dielectric property Hybrid film
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Designing Adaptive Multiple Dependent State Sampling Plan for Accelerated Life Tests 被引量:1
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作者 Pramote Charongrattanasakul Wimonmas Bamrungsetthapong Poom Kumam 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期1631-1651,共21页
A novel adaptive multiple dependent state sampling plan(AMDSSP)was designed to inspect products from a continuous manufacturing process under the accelerated life test(ALT)using both double sampling plan(DSP)and multi... A novel adaptive multiple dependent state sampling plan(AMDSSP)was designed to inspect products from a continuous manufacturing process under the accelerated life test(ALT)using both double sampling plan(DSP)and multiple dependent state sampling plan(MDSSP)concepts.Under accelerated conditions,the lifetime of a product follows the Weibull distribution with a known shape parameter,while the scale parameter can be determined using the acceleration factor(AF).The Arrhenius model is used to estimate AF when the damaging process is temperature-sensitive.An economic design of the proposed sampling plan was also considered for the ALT.A genetic algorithm with nonlinear optimization was used to estimate optimal plan parameters to minimize the average sample number(ASN)and total cost of inspection(TC)under both producer’s and consumer’s risks.Numerical results are presented to support the AMDSSP for the ALT,while performance comparisons between the AMDSSP,the MDSSP and a single sampling plan(SSP)for the ALT are discussed.Results indicated that the AMDSSP was more flexible and efficient for ASN and TC than the MDSSP and SSP plans under accelerated conditions.The AMDSSP also had a higher operating characteristic(OC)curve than both the existing sampling plans.Two real datasets of electronic devices for the ALT at high temperatures demonstrated the practicality and usefulness of the proposed sampling plan. 展开更多
关键词 accelerated life test acceleration factor adaptive of multiple dependent state sampling plan average sample number total cost of inspection weibull distribution
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The acceleration of a high-charge electron bunch to 10 GeV in a 10-cm nanoparticle-assisted wakefield accelerator 被引量:1
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作者 Constantin Aniculaesei Thanh Ha +24 位作者 Samuel Yoffe Lance Labun Stephen Milton Edward McCary Michael M.Spinks Hernan J.Quevedo Ou Z.Labun Ritwik Sain Andrea Hannasch Rafal Zgadzaj Isabella Pagano Jose A.Franco-Altamirano Martin L.Ringuette Erhart Gaul Scott V.Luedtke Ganesh Tiwari Bernhard Ersfeld Enrico Brunetti Hartmut Ruhl Todd Ditmire Sandra Bruce Michael E.Donovan Michael C.Downer Dino A.Jaroszynski Bjorn Manuel Hegelich 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第1期15-24,共10页
An intense laser pulse focused onto a plasma can excite nonlinear plasma waves.Under appropriate conditions,electrons from the background plasma are trapped in the plasma wave and accelerated to ultra-relativistic vel... An intense laser pulse focused onto a plasma can excite nonlinear plasma waves.Under appropriate conditions,electrons from the background plasma are trapped in the plasma wave and accelerated to ultra-relativistic velocities.This scheme is called a laser wakefield accelerator.In this work,we present results from a laser wakefield acceleration experiment using a petawatt-class laser to excite the wakefields as well as nanoparticles to assist the injection of electrons into the accelerating phase of the wakefields.We find that a 10-cm-long,nanoparticle-assisted laser wakefield accelerator can generate 340 pC,10±1.86 GeV electron bunches with a 3.4 GeV rms convolved energy spread and a 0.9 mrad rms divergence.It can also produce bunches with lower energies in the 4–6 GeV range. 展开更多
关键词 accelerATION NANOPARTICLE CHARGE
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Cross-Linking of Sago Starch with Furan and Bismaleimide via the Diels-Alder Reaction
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作者 Henky Muljana Ivana Hasjem +5 位作者 Merianawati Sinatra Dicky Joshua Pesireron MichaelWilbert Puradisastra Ryan Hartono Kevin Yovan Hermanto Tony Handoko 《Journal of Renewable Materials》 EI 2023年第12期4039-4060,共22页
This research paper describes the synthesis of thermo-reversible cross-linking of sago starch by grafting a furan pendant group(methyl 2-furoate)onto the starch backbone,followed by a Diels-Alder(DA)reaction of the fu... This research paper describes the synthesis of thermo-reversible cross-linking of sago starch by grafting a furan pendant group(methyl 2-furoate)onto the starch backbone,followed by a Diels-Alder(DA)reaction of the furan functional group with 1,1′-(methylenedi-4,1-phenylene)bismaleimide(BM).The proof of principles was provided by FTIR and 1H-NMR analyses.The relevant FTIR peaks are the carbonyl peak(υC=O sym)at 1721 cm^(−1);the two peaks appeared after DA cross-linking,i.e.,at 1510 cm^(−1)(corresponding toυCH=CH BM aromatic rings,stretching vibrations),and at 1173 cm^(−1)(assigned to cycloadduct(C-O-C,δDA ring))while the^(1)H-NMR result shows evidence for the presence of a furan ring in the starch matrices(in the range ofδ6.3-7.5 ppm).The crosslinked starch product is indeed thermally reversible,as is evident from the appearance of exothermal(DA,temperature range of 50℃-70℃)and endothermal(retro DA,temperature range of 125℃-150℃)transitions in the DSC thermograms.This paper not only proves the thermal reversibility but also demonstrates that the final product properties(chemical,morphology,and thermal stability)can be tuned by varying the annealing temperature,BM intake,and reaction time. 展开更多
关键词 DIELS-ALDER STARCH biopolymers thermal-reversible cross-linking
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A Rare Entity of Accelerated Chronic Lymphocytic Leukemia: A Report of Two Cases and Review of Literature
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作者 Zahra Kmira Ben Yahya Noura +7 位作者 Chembah Wafa Ben Sayed Nesrine Chiba Dorra Bouteraa Walid Zaier Monia Ben Youssef Yosra Haifa Regaieg Khelif Abderrahim 《Health》 2023年第8期861-870,共10页
Background: Accelerated-chronic lymphocytic leukemia (A-CLL) is a rare disease entity as it represents less than 1% of all reported cases of chronic lymphoid leukemia (CLL). Moreover, it is most likely an under diagno... Background: Accelerated-chronic lymphocytic leukemia (A-CLL) is a rare disease entity as it represents less than 1% of all reported cases of chronic lymphoid leukemia (CLL). Moreover, it is most likely an under diagnosed entity due to its rarity and the non-standardized practice of lymph node biopsy in CLL. Purpose: The aims of our work are to establish the diagnosis of A-CLL and to study the prognosis and treatment of this rare entity. Method: here, we report the clinical presentation and the follow up of two cases of A-CLL. Results: Distinguishing Richter transformation (RT) from A-CLL is important as it may result in a major change in disease management. The prognosis of A-CLL is intermediate between CLL and RT. The prognosis is mainly poor due to a predominance of poor prognostic markers including an increasing number of p53-positive cases. Conclusion: To this date, no prospective study has been led to define the best treatment for A-CLL. The shorter survival of A-CLL when compared to typical CLL implies the need of a more aggressive treatment. 展开更多
关键词 accelerated Chronic Lymphocytic Leukemia Richter Transformation PROGNOSIS Treatment
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A study of grid failure mode drivers and methods for accelerated life testing of a 30cm diameter ion thruster
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作者 孙明明 龙建飞 +3 位作者 陈娟娟 杨威 郭伟龙 陈新伟 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第11期122-132,共11页
In view of the high cost caused by the 1:1 lifetime verification test of ion thrusters,the lifetime acceleration test should be considered.This work uses the PIC-MCC(Particle-in-Cell MonteCarlo Collision)method to ana... In view of the high cost caused by the 1:1 lifetime verification test of ion thrusters,the lifetime acceleration test should be considered.This work uses the PIC-MCC(Particle-in-Cell MonteCarlo Collision)method to analyze the five failure factors that lead to the failure of the accelerator grid of a 30 cm diameter ion thruster under the working mode of 5 k W.Meanwhile,the acceleration stress levels corresponding to different failure factors are obtained.The results show that background pressure has the highest stress level on the grid's erosion.The accelerator grid aperture's mass sputtering rate under the rated vacuum degree(1×10^(-4)Pa)of 5 k W work mode is 8.78 times that of the baseline vacuum degree(1×10^(-6)Pa),and the mass sputtering rate under worse vacuum degree(5×10^(-3)Pa)is 5.08 times that of 1×10^(-4)Pa.Under the influence of the other four failure factors,namely,the voltage of the accelerator grid,upstream plasma density,the screen grid voltage and mass utilization efficiency,the mass sputtering rates of the accelerator grid hole are 2.32,2.67,1.98 and 2.51 times those of the accelerator grid hole under baseline condition,respectively.The ion sputtering results of two 30 cm diameter ion thrusters(both installed with new grids assembly)after working for 1000 h show that the mass sputtering rate of the accelerator grid hole under vacuum conditions of 5×10^(-3)Pa is 4.54 times that under the condition of 1×10^(-4)Pa,and the comparison error between simulation results and test results of acceleration stress is about 10%.In the subsequent ion thruster lifetime verification,the working vacuum degree can be adjusted according to the acceleration stress level of background pressure,so as to shorten the test time and reduce the test cost. 展开更多
关键词 ion thruster failure factors acceleration stress level
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A Novel Process of CO_(2) Reduction and CO_(2) Sequestration Through an Innovative Accelerated Carbonation Technique
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作者 Akshay Ramesh Bura B Kondraivendhan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第5期1105-1117,共13页
The efiect of an innovative accelerated carbonation curing technique was evaluated on concrete containing natural zeolite powder and fine aggregate as partial replacement to alleviate the CO_(2) emission up to a certa... The efiect of an innovative accelerated carbonation curing technique was evaluated on concrete containing natural zeolite powder and fine aggregate as partial replacement to alleviate the CO_(2) emission up to a certain extent from the concrete production industry and improve sequestration of CO_(2) into the concrete matrix in a stable form.An accelerated carbonation curing was accomplished by subjecting the concrete specimens to 0.5 and 0.75 M concentrations of sodium bicarbonate(NaHCO_(3)) solutions up to a curing age of 180 days after the initial 28 days of normal water curing.Tests for carbonation depth,pH value,compressive strength,calcium carbonate(CaCO_(3))content,X-ray difiraction,and thermogravimetric(TGA)analyses and Fourier transform infrared spectroscopy(FTIR)were performed to measure the extent of carbonation.The obtained results showed an increment in average compressive strength for the zeolite concrete(ZLC)mixes exposed to accelerated carbonation curing.The ZLC mixes exposed to increasing NaHCO_(3) solution concentration and exposure period exhibited greater carbonation depth and decreased pH at each depth interval indicating higher CO_(2) sequestration within the concrete matrix.The results obtained from the microstructural analysis(XRD,TGA,and FTIR)and CaCO_(3) content measurements confirm that the higher amount of CaCO_(3) formation provides a clear indication of the carbonation enhancement and CO_(2) sequestration within the concrete matrix and in turn contributing to the global warming reduction. 展开更多
关键词 CO_(2)sequestration accelerated carbonation natural zeolite calcium carbonate
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The Accelerated Expansion of the Universe
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作者 Ardeshir Irani 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第2期407-410,共4页
We use experimental data from Distant Type 1a Supernovae to calculate the Observed Magnitude (m - M) which is the Apparent Magnitude (m) minus the Absolute Magnitude (M) for different values of the Redshift ... We use experimental data from Distant Type 1a Supernovae to calculate the Observed Magnitude (m - M) which is the Apparent Magnitude (m) minus the Absolute Magnitude (M) for different values of the Redshift z which gives us the Distance Modulus. Then, we calculate the average velocity and average acceleration for different z values and plot them as a function of time. The expansion of the space of our 3-D Universe is exponential and it will end with a Big Bang as four 3-D Universes of which we are one will come together to form one 4-D expanding spatial Universe. 展开更多
关键词 Distance Modulus REDSHIFT accelerated Expansion Exponentially Expanding Space Big Bang
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Inference for accelerated bivariate dependent competing risks model based on Archimedean copulas under progressive censoring
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作者 ZHANG Chun-fang SHI Yi-min WANG Liang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第4期475-492,共18页
Dependent competing risks model is a practical model in the analysis of lifetime and failure modes.The dependence can be captured using a statistical tool to explore the re-lationship among failure causes.In this pape... Dependent competing risks model is a practical model in the analysis of lifetime and failure modes.The dependence can be captured using a statistical tool to explore the re-lationship among failure causes.In this paper,an Archimedean copula is chosen to describe the dependence in a constant-stress accelerated life test.We study the Archimedean copula based dependent competing risks model using parametric and nonparametric methods.The parametric likelihood inference is presented by deriving the general expression of likelihood function based on assumed survival Archimedean copula associated with the model parameter estimation.Combining the nonparametric estimation with progressive censoring and the non-parametric copula estimation,we introduce a nonparametric reliability estimation method given competing risks data.A simulation study and a real data analysis are conducted to show the performance of the estimation methods. 展开更多
关键词 dependent competing risks model accelerated life tests Archimedean copula nonparametric reliability estimation
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Quality Improvement of Recycled Concrete Aggregate by Accelerated Carbonation under Different Pressure
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作者 丁亚红 武军 +3 位作者 ZHANG Xianggang XU Ping NING Wei LI Yajing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第3期623-631,共9页
Due to the presence of old mortar (OM) and interfacial transition zone (ITZ),recycled concrete aggregate (RCA) is inferior to natural aggregate (NA).The purpose of this paper was to study the effect of accelerated car... Due to the presence of old mortar (OM) and interfacial transition zone (ITZ),recycled concrete aggregate (RCA) is inferior to natural aggregate (NA).The purpose of this paper was to study the effect of accelerated carbonation on the macro-properties and micro-properties of RCA under different pressure(0.05,0.15,0.30 MPa).The macro-property tests included colour change,apparent density,water absorption,and crushing value of RCA.The micro-property tests included scanning electron microscopy (SEM),X-ray diffraction (XRD),thermogravimetry-differential scanning calorimetry (TG-DSC),and Vickers micro-hardness(VMH).The results showed that the change trends of apparent density,water absorption,and crushing value of RCA displayed exponential relationships as pressure increasing,with the optimum pressure of 0.30 MPa.SEM images indicated that the calcite caused by the hydration products in RCA and the Ca(OH)_(2) derived from saturated lime water improved the properties of RCA;as the apparent density increased,the water absorption and crushing value decreased.The results of XRD and TG-DSC indicated that,as the pressure increased,the masses of Ca(OH)_(2) in carbonated RCA gradually decreased,while those of CaCO_(3) gradually increased,which demonstrated that the carbonation degree gradually increased.Besides,ITZ-2 was the weakest phase in RCA,but its improvement degree of VMH by accelerated carbonation was higher than that of OM.However,RCA was not completely carbonated,but only carbonated in a certain depth after 24 h accelerated carbonation. 展开更多
关键词 recycled concrete aggregate treatment method accelerated carbonation interfacial transition zone saturated lime water CALCITE
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Molecular insight into the GaP(110)-water interface using machine learning accelerated molecular dynamics
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作者 Xue-Ting Fan Xiao-Jian Wen +1 位作者 Yong-Bin Zhuang Jun Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期239-247,I0006,共10页
GaP has been shown to be a promising photoelectrocatalyst for selective CO_(2)reduction to methanol.Due to the relevance of the interface structure to important processes such as electron/proton transfer,a detailed un... GaP has been shown to be a promising photoelectrocatalyst for selective CO_(2)reduction to methanol.Due to the relevance of the interface structure to important processes such as electron/proton transfer,a detailed understanding of the GaP(110)-water interfacial structure is of great importance.Ab initio molecular dynamics(AIMD)can be used for obtaining the microscopic information of the interfacial structure.However,the GaP(110)-water interface cannot converge to an equilibrated structure at the time scale of the AIMD simulation.In this work,we perform the machine learning accelerated molecular dynamics(MLMD)to overcome the difficulty of insufficient sampling by AIMD.With the help of MLMD,we unravel the microscopic information of the structure of the GaP(110)-water interface,and obtain a deeper understanding of the mechanisms of proton transfer at the GaP(110)-water interface,which will pave the way for gaining valuable insights into photoelectrocatalytic mechanisms and improving the performance of photoelectrochemical cells. 展开更多
关键词 PHOTOELECTROCATALYSIS GaP(110)-water interface Machine learning accelerated molecular dynamics
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