In this paper, a new probability distribution is proposed by using Marshall and Olkin transformation. Some of its properties such as moments, moment generating function, order statistics and reliability functions are ...In this paper, a new probability distribution is proposed by using Marshall and Olkin transformation. Some of its properties such as moments, moment generating function, order statistics and reliability functions are derived. The method of </span><span style="font-family:Verdana;">maximum likelihood is used to estimate the model parameters. The graphs of the reliability function and hazard rate function are plotted by taken some values of the parameters. Three real life applications are introduced to compare the behaviour of the new distribution with other distributions.展开更多
In this paper, resonance energies and excitation energies of doubly 2<em>sns</em> <sup>1,3</sup><em>S</em><sup>e</sup>, 2<em>snp</em> <sup>1,3</sup&...In this paper, resonance energies and excitation energies of doubly 2<em>sns</em> <sup>1,3</sup><em>S</em><sup>e</sup>, 2<em>snp</em> <sup>1,3</sup><em>P</em><sup>0</sup>, 2<em>pnp</em> <sup>1,3</sup><em>D</em><sup>e</sup>, 2<em>pnd</em> <sup>1,3</sup><em>F</em><sup>0</sup> and 2<em>pnf</em> <sup>1,3</sup><em>G</em><sup>e</sup> excited states of the helium isoelectronic sequence with <em>Z</em> <span style="white-space:nowrap;">≤</span> 10 are calculated. Calculations are carried out in the framework of the variational procedure of the formalism of the Screening Constant per Unit Nuclear Charge (SCUNC). New correlated wave function of Hylleraas type is used. Precise resonance and excitation energies are tabulated and good agreement is obtained when a comparison is made with available literature values.展开更多
Quantitative analysis of digital images requires detection and segmentation of the borders of the object of interest. Accurate segmentation is required for volume determination, 3D rendering, radiation therapy, and su...Quantitative analysis of digital images requires detection and segmentation of the borders of the object of interest. Accurate segmentation is required for volume determination, 3D rendering, radiation therapy, and surgery planning. In medical images, segmentation has traditionally been done by human experts. Substantial computational and storage requirements become especially acute when object orientation and scale have to be considered. Therefore, automated or semi-automated segmentation techniques are essential if these software applications are ever to gain widespread clinical use. Many methods have been proposed to detect and segment 2D shapes, most of which involve template matching. Advanced segmentation techniques called Snakes or active contours have been used, considering deformable models or templates. The main purpose of this work is to apply segmentation techniques for the definition of 3D organs (anatomical structures) when big data information has been stored and must be organized by the doctors for medical diagnosis. The processes would be implemented in the CT images from patients with COVID-19.展开更多
In this study,we obtain the universal function corresponding to the diffractive process and show that the cross section exhibits geometrical scaling.It is observed that diffractive theory according to the color dipole...In this study,we obtain the universal function corresponding to the diffractive process and show that the cross section exhibits geometrical scaling.It is observed that diffractive theory according to the color dipole approach at small-x is a convenient framework that reveals the color transparency and saturation phenomena.We also calculate the contribution of heavy quark production in the diffractive cross section at high energy that is determined by the small size dipole configuration.The ratio of the diffractive cross section to the total cross section in electron-proton collision is the other important quantity that is computed in this work.展开更多
The traditional linear programming model is deterministic. The way that uncertainty is handled is to compute the range of optimality. After the optimal solution is obtained, typically by the simplex method, one consid...The traditional linear programming model is deterministic. The way that uncertainty is handled is to compute the range of optimality. After the optimal solution is obtained, typically by the simplex method, one considers the effect of varying each objective function coefficient, one at a time. This yields the range of optimality within which the decision variables remain constant. This sensitivity analysis is useful for helping the analyst get a sense for the problem. However, it is unrealistic because objective function coefficients tend not to stand still. They are typically profit contributions from products sold and are subject to randomly varying selling prices. In this paper, a realistic linear program is created for simultaneously randomizing the coefficients from any probability distribution. Furthermore, we present a novel approach for designing a copula of random objective function coefficients according to a specified rank correlation. The corresponding distribution of objective function values is created. This distribution is examined directly for central tendency, spread, skewness and extreme values for the purpose of risk analysis. This enables risk analysis and business analytics, emerging topics in education and preparation for the knowledge economy.展开更多
By applying nonequilibrium Green’s functions (NEGF) in combination with the density functional theory (DFT), we investigate the electronic transport properties of gated phenalenyl molecular devices with two different...By applying nonequilibrium Green’s functions (NEGF) in combination with the density functional theory (DFT), we investigate the electronic transport properties of gated phenalenyl molecular devices with two different contact geometries. The calculated results show that electronic transport properties of the two different devices can be modulated by external transverse gates. When the molecule contacts the Au electrodes through two second-nearest sites, the current-voltage (<em>I</em>-<em>V</em>) characteristic curves are symmetric and suppressed by the gate electrodes. However, a rectifying behavior will occur when the electrodes connect the molecule on both sides, one second-nearest site and one third-nearest site, respectively. Mechanisms for such phenomena are proposed and these findings suggest a new opportunity for developing molecular devices.展开更多
背景:血流限制训练作为一种新兴训练方式,可有效增加肌肉力量和容积、提高肌肉功能,为运动干预功能障碍提供一种新途径。而该领域目前从机制到应用存在诸多争议。目的:探究近年来血流限制训练应用的研究热点与主要内容,为该领域未来研...背景:血流限制训练作为一种新兴训练方式,可有效增加肌肉力量和容积、提高肌肉功能,为运动干预功能障碍提供一种新途径。而该领域目前从机制到应用存在诸多争议。目的:探究近年来血流限制训练应用的研究热点与主要内容,为该领域未来研究发展提供新的思路和方向。方法:运用CiteSpace 5.6.R3软件对Web of Science核心合集数据库中2009至2019年有关血流限制训练的441篇文献进行可视化分析,综合图谱和数据结果,结合关键文献分析研究热点。结果与结论:①血流限制训练研究自21世纪以来呈上升趋势,主要以美国、日本及其机构发表成果较多且影响力较高;②研究主题发展趋势逐渐从对局部组织器官的影响向对身体机能影响发展,从普通人群训练应用向特殊人群干预治疗发展;③热点关键词为血流限制、力量、骨骼肌、肌肥大、生长激素和适应,研究热点主要内容包括不同生理适应机制、训练方法学影响变量、功能障碍人群康复应用及心血管循环功能影响等;④低负荷血流限制训练作为一种运动干预的有效方法,逐渐被应用在骨骼肌肉、心血管、代谢及神经疾病的临床治疗或康复干预中,未来研究可围绕血流限制训练长期运动效益、运动生理适应机制、不同人群应用效果、训练方法安全性等内容发展。展开更多
Let S_s*be the class of normalized functions f defined in the open unit■such that the quantity zf’(z)/f(z)lies in an eight-shaped region in the right-half plane and satisfies the condition■.In this paper,we aim to ...Let S_s*be the class of normalized functions f defined in the open unit■such that the quantity zf’(z)/f(z)lies in an eight-shaped region in the right-half plane and satisfies the condition■.In this paper,we aim to investigate Toeplitz determinants for the inverse of this function classes S_s*associated with sine function.展开更多
In this paper,we consider the generalized Moser-type inequalities,sayφ(n)≥kπ(n),where k is an integer greater than 1,φ(n)is Euler function andπ(n)is the prime counting function.Using computer,Pierre Dusart’s ine...In this paper,we consider the generalized Moser-type inequalities,sayφ(n)≥kπ(n),where k is an integer greater than 1,φ(n)is Euler function andπ(n)is the prime counting function.Using computer,Pierre Dusart’s inequality onπ(n)and Rosser-Schoenfeld’s inequality involvingφ(n),we give all solutions ofφ(n)=2π(n)andφ(n)=3π(n),respectively.Moreover,we obtain the best lower bound that Moser-type inequalitiesφ(n)>kπ(n)hold for k=2,3.As consequences,we show that every even integer greater than 210 is the sum of two coprime composite,every odd integer greater than 175 is the sum of three pairwise coprime odd composite numbers,and every odd integer greater than 53 can be represented as p+x+y,where p is prime,x and y are composite numbers satisfying that p,and x and y are pairwise coprime.Specially,we give a new equivalent form of Strong Goldbach Conjecture.展开更多
Extreme values of wind speed were studied based on the highly detailed ERA5 dataset covering the central part of the Kara Sea. Cases in which the ice coverage of the cells exceeded 15% were filtered. Our study shows t...Extreme values of wind speed were studied based on the highly detailed ERA5 dataset covering the central part of the Kara Sea. Cases in which the ice coverage of the cells exceeded 15% were filtered. Our study shows that the wind speed extrema obtained from station observations, as well as from modelling results in the framework of mesoscale models, can be divided into two groups according to their probability distribution laws. One group is specifically designated as black swans, with the other referred to as dragons (or dragon-kings). In this study we determined that the data of ERA5 accurately described the swans, but did not fully reproduce extrema related to the dragons;these extrema were identified only in half of ERA5 grid points. Weibull probability distribution function (PDF) parameters were identified in only a quarter of the pixels. The parameters were connected almost deterministically. This converted the Weibull function into a one-parameter dependence. It was not clear whether this uniqueness was a consequence of the features of the calculation algorithm used in ERA5, or whether it was a consequence of a relatively small area being considered, which had the same wind regime. Extremes of wind speed arise as mesoscale features and are associated with hydrodynamic features of the wind flow. If the flow was non-geostrophic and if its trajectory had a substantial curvature, then the extreme velocities were distributed according to a rule similar to the Weibull law.展开更多
Exponential integral for real arguments is evaluated by employing a fast-converging power series originally developed for the resolution of Grandi’s paradox. Laguerre’s historic solution is first recapitulated and t...Exponential integral for real arguments is evaluated by employing a fast-converging power series originally developed for the resolution of Grandi’s paradox. Laguerre’s historic solution is first recapitulated and then the new solution method is described in detail. Numerical results obtained from the present series solution are compared with the tabulated values correct to nine decimal places. Finally, comments are made for the further use of the present approach for integrals involving definite functions in denominator.展开更多
In this article, we consider the construction of a SVIR (Susceptible, Vaccinated, Infected, Recovered) stochastic compartmental model of measles. We prove that the deterministic solution is asymptotically the average ...In this article, we consider the construction of a SVIR (Susceptible, Vaccinated, Infected, Recovered) stochastic compartmental model of measles. We prove that the deterministic solution is asymptotically the average of the stochastic solution in the case of small population size. The choice of this model takes into account the random fluctuations inherent to the epidemiological characteristics of rural populations of Niger, notably a high prevalence of measles in children under 5, coupled with a very low immunization coverage.展开更多
This paper considers the adaptive neuro-fuzzy control scheme to solve the output tracking problem for a class of strict-feedback nonlinear systems.Both asymmetric output constraints and input saturation are considered...This paper considers the adaptive neuro-fuzzy control scheme to solve the output tracking problem for a class of strict-feedback nonlinear systems.Both asymmetric output constraints and input saturation are considered.An asymmetric barrier Lyapunov function with time-varying prescribed performance is presented to tackle the output-tracking error constraints.A high-gain observer is employed to relax the requirement of the Lipschitz continuity about the nonlinear dynamics.To avoid the"explosion of complexity",the dynamic surface control(DSC)technique is employed to filter the virtual control signal of each subsystem.To deal with the actuator saturation,an additional auxiliary dynamical system is designed.It is theoretically investigated that the parameter estimation and output tracking error are semi-global uniformly ultimately bounded.Two simulation examples are conducted to verify the presented adaptive fuzzy controller design.展开更多
Individuals with amnestic mild cognitive impairment(aMCI)have a high risk of developing Alzheimer’s disease.Although repetitive transcranial magnetic stimulation(rTMS)is considered a potentially effective treatment f...Individuals with amnestic mild cognitive impairment(aMCI)have a high risk of developing Alzheimer’s disease.Although repetitive transcranial magnetic stimulation(rTMS)is considered a potentially effective treatment for cognitive impairment in patients with aMCI,the neuroimaging mechanisms are poorly understood.Therefore,we performed a double-blind randomized sham-controlled trial in which rTMS was applied to the left dorsolateral prefrontal cortex of aMCI patients recruited from a community near the Third Hospital Affiliated to Sun Yat-sen University,China.Twenty-four patients with aMCI were randomly assigned to receive true rTMS(treatment group,n=12,6 men and 6 women;age 65.08±4.89 years)or sham stimulation(sham group,n=12,5 men and 7 women;age 64.67±4.77 years).rTMS parameters included a stimulation frequency of 10 Hz,stimulation duration of 2 seconds,stimulation interval of 8 seconds,20 repetitions at 80%of the motor threshold,and 400 pulses per session.rTMS/sham stimulation was performed five times per week over a period of 4 consecutive weeks.Our results showed that compared with baseline,Montreal Cognitive Assessment scores were significantly increased and the value of the amplitude of low-frequency fluctuation(ALFF)was significantly increased at the end of treatment and 1 month after treatment.Compared with the sham group,the ALFF values in the right inferior frontal gyrus,triangular part of the inferior frontal gyrus,right precuneus,left angular gyrus,and right supramarginal gyrus were significantly increased,and the ALFF values in the right superior frontal gyrus were significantly decreased in the treatment group.These findings suggest that high-frequency rTMS can effectively improve cognitive function in aMCI patients and alter spontaneous brain activity in cognitive-related brain areas.This study was approved by the Ethics Committee of Shenzhen Baoan Hospital of Southern Medical University,China(approval No.BYL20190901)on September 3,2019 and registered in the Chinese Clinical Trials Registry(regi展开更多
This paper provides a review of methods of assessing a fragmentation weapon’s effectiveness against a point target or an area target with keeping the focus on the necessity of using the Carleton damage function with ...This paper provides a review of methods of assessing a fragmentation weapon’s effectiveness against a point target or an area target with keeping the focus on the necessity of using the Carleton damage function with the correct shape factor.First,cookie-cutter damage functions are redefined to preserve the shape factor of and to have the same lethal area as the corresponding Carleton damage function.Then,closed-form solutions of the effectiveness methods are obtained by using those cookie-cutter damage functions and the Carleton damage function.Finally,the closed-form solutions are applied to calculate the probability of damaging a point target and the expected fractional damage to an area target for several attack scenarios by using cookie-cutter damage functions and the Carleton damage functions with different shape factors.The comparison of the calculation results shows that using cookie-cutter damage functions or the Carleton damage function with a wrong shape factor results in quite significant differences from using the original Carleton damage function with a correct shape factor when weapon’s delivery error deviations are less than or comparable to the lengths of the lethal area and the aim point is far from a target.The effectiveness methods improved in this paper will be useful for mission planning utilizing the precision-guided munitions in circumstances where the collateral damage should be reduced.展开更多
<strong>Background:</strong> Cell replacement therapies have been evaluated in recent years as an alternative for various retinal pathologies to evaluate the therapeutic efficacy of cell therapy, it is imp...<strong>Background:</strong> Cell replacement therapies have been evaluated in recent years as an alternative for various retinal pathologies to evaluate the therapeutic efficacy of cell therapy, it is important to measure the severity of the disease. The aim of this study was to evaluate the effect of umbilical cord derived Mesenchymal Stem Cell (UC-MSC) implantation on severity of Retinitis Pigmentosa (RP). <strong>Methods:</strong> This single-center, clinical study included data of 138 eyes of 92 patients who had a confirmed diagnosis of RP and received stem cell implantation to the suprachoroidal area with a surgical procedure. Patients were evaluated before and 1 year after the surgery regarding to the outcome measures of Best Corrected Visual Acuity (BCVA), Optical Coherence Tomography (OCT) and Visual Field (VF) tests. BCVA, VF width and ellipsoid zone (EZ) width on OCT were recorded for each patient and a scoring criterion was established for each variable varying from 0 to 5 depending on its distribution. The cumulative score (from 0 to 15) was used to classify disease severity from grade 0 to 5. <strong>Results:</strong> All of the patients completed 12-month follow-up period. The median age of the patients was 40.8 years, 46% were female, 77% had been diagnosed within 10 years and 41% had a family history. 79% of the patients with family history had autosomal recessive inheritance pattern. There were statistically significant improvements in the mean BCVA and VF scores during the study (p < 0.05). The mean score and the mean grade of the disease also improved after the treatment (p < 0.05). There was a negative correlation between BCVA improvement and scoring and grading of the disease. <strong>Conclusions:</strong> This study demonstrated beneficial effect of suprachoroidally applied UC-MSCs on BCVA, VF and the severity score and grade of the disease during 12-month follow-up period. Cell mediated therapy based on the secretion of Growth Factors (GFs) seems to be an effective and safe option for the 展开更多
The Gauss-linking integral for disjoint oriented smooth closed curves is derived linking integrals from the Biot-Savart description of the magnetic field. DeTurck and Gluck extend this linking from 3-space <em>R...The Gauss-linking integral for disjoint oriented smooth closed curves is derived linking integrals from the Biot-Savart description of the magnetic field. DeTurck and Gluck extend this linking from 3-space <em>R</em><sup>3</sup> to <em>SU</em> (2) space of the unit 3-sphere and hyperbolic space in Minkowski <em>R</em><sup>1,3</sup>. I herein extend Gauss-linking to self-linking and develop the concept of self-dual, which is then applied to gravitomagnetic dynamics. My purpose is to redefine Wheeler’s <em>geon</em> from unstable field structures based on the electromagnetic field to self-stabilized gravitomagnetic field structures.展开更多
<strong>Background:</strong> <span><span><span style="font-family:""><span style="font-family:Verdana;">Pilates has been shown to be an effective interventi...<strong>Background:</strong> <span><span><span style="font-family:""><span style="font-family:Verdana;">Pilates has been shown to be an effective intervention for adults with musculoskeletal conditions with only a few examples available in the li</span><span style="font-family:Verdana;">terature for children. As musculoskeletal pain is a major symptom expe</span><span style="font-family:Verdana;">rienced by children with Hypermobility Spectrum Disorder (HSD), they may benefit from practicing Pilates to improve postural alignment, strength and motor control to effectively distribute movement load and decrease adverse load through involved joints. </span><b><span style="font-family:Verdana;">Method:</span></b><span style="font-family:Verdana;"> This study aims to evaluate the impact of a Physiotherapy-led Pilates intervention on school aged children with HSD and the benefits of this approach on pain, physical function and quality of life when delivered in a community-based model of care. A single-case experimental design (SCED) that incorporates a multiple baseline design will be used. Children with HSD, aged from 8 to 12 years, will commence concurrently in this study. Participants will undergo multiple assessments through all phases of the study which incorporates an A-B-A withdrawal design. The initial baseline period will be randomised from 5 to 7 weeks duration, then participants will enter the intervention period for 8 weeks followed by a withdrawal period of 5 weeks. The Physiotherapy-led Pilates intervention will consist of individual, 45 minute bi-weekly sessions, performed on both mat and the Pilates Reformer with an additional home program of mat exercises performed weekly. The study hypotheses are that children will show: 1) a decrease in pain;2) an increase in their physical function as measured by muscle strength, postural control, fatigue and physical activity levels;and 3) an improvement in their Health Related Quality of Life in the domains of physical, emotional, social and school functioning. </s展开更多
文摘In this paper, a new probability distribution is proposed by using Marshall and Olkin transformation. Some of its properties such as moments, moment generating function, order statistics and reliability functions are derived. The method of </span><span style="font-family:Verdana;">maximum likelihood is used to estimate the model parameters. The graphs of the reliability function and hazard rate function are plotted by taken some values of the parameters. Three real life applications are introduced to compare the behaviour of the new distribution with other distributions.
文摘In this paper, resonance energies and excitation energies of doubly 2<em>sns</em> <sup>1,3</sup><em>S</em><sup>e</sup>, 2<em>snp</em> <sup>1,3</sup><em>P</em><sup>0</sup>, 2<em>pnp</em> <sup>1,3</sup><em>D</em><sup>e</sup>, 2<em>pnd</em> <sup>1,3</sup><em>F</em><sup>0</sup> and 2<em>pnf</em> <sup>1,3</sup><em>G</em><sup>e</sup> excited states of the helium isoelectronic sequence with <em>Z</em> <span style="white-space:nowrap;">≤</span> 10 are calculated. Calculations are carried out in the framework of the variational procedure of the formalism of the Screening Constant per Unit Nuclear Charge (SCUNC). New correlated wave function of Hylleraas type is used. Precise resonance and excitation energies are tabulated and good agreement is obtained when a comparison is made with available literature values.
文摘Quantitative analysis of digital images requires detection and segmentation of the borders of the object of interest. Accurate segmentation is required for volume determination, 3D rendering, radiation therapy, and surgery planning. In medical images, segmentation has traditionally been done by human experts. Substantial computational and storage requirements become especially acute when object orientation and scale have to be considered. Therefore, automated or semi-automated segmentation techniques are essential if these software applications are ever to gain widespread clinical use. Many methods have been proposed to detect and segment 2D shapes, most of which involve template matching. Advanced segmentation techniques called Snakes or active contours have been used, considering deformable models or templates. The main purpose of this work is to apply segmentation techniques for the definition of 3D organs (anatomical structures) when big data information has been stored and must be organized by the doctors for medical diagnosis. The processes would be implemented in the CT images from patients with COVID-19.
文摘In this study,we obtain the universal function corresponding to the diffractive process and show that the cross section exhibits geometrical scaling.It is observed that diffractive theory according to the color dipole approach at small-x is a convenient framework that reveals the color transparency and saturation phenomena.We also calculate the contribution of heavy quark production in the diffractive cross section at high energy that is determined by the small size dipole configuration.The ratio of the diffractive cross section to the total cross section in electron-proton collision is the other important quantity that is computed in this work.
文摘The traditional linear programming model is deterministic. The way that uncertainty is handled is to compute the range of optimality. After the optimal solution is obtained, typically by the simplex method, one considers the effect of varying each objective function coefficient, one at a time. This yields the range of optimality within which the decision variables remain constant. This sensitivity analysis is useful for helping the analyst get a sense for the problem. However, it is unrealistic because objective function coefficients tend not to stand still. They are typically profit contributions from products sold and are subject to randomly varying selling prices. In this paper, a realistic linear program is created for simultaneously randomizing the coefficients from any probability distribution. Furthermore, we present a novel approach for designing a copula of random objective function coefficients according to a specified rank correlation. The corresponding distribution of objective function values is created. This distribution is examined directly for central tendency, spread, skewness and extreme values for the purpose of risk analysis. This enables risk analysis and business analytics, emerging topics in education and preparation for the knowledge economy.
文摘By applying nonequilibrium Green’s functions (NEGF) in combination with the density functional theory (DFT), we investigate the electronic transport properties of gated phenalenyl molecular devices with two different contact geometries. The calculated results show that electronic transport properties of the two different devices can be modulated by external transverse gates. When the molecule contacts the Au electrodes through two second-nearest sites, the current-voltage (<em>I</em>-<em>V</em>) characteristic curves are symmetric and suppressed by the gate electrodes. However, a rectifying behavior will occur when the electrodes connect the molecule on both sides, one second-nearest site and one third-nearest site, respectively. Mechanisms for such phenomena are proposed and these findings suggest a new opportunity for developing molecular devices.
文摘背景:血流限制训练作为一种新兴训练方式,可有效增加肌肉力量和容积、提高肌肉功能,为运动干预功能障碍提供一种新途径。而该领域目前从机制到应用存在诸多争议。目的:探究近年来血流限制训练应用的研究热点与主要内容,为该领域未来研究发展提供新的思路和方向。方法:运用CiteSpace 5.6.R3软件对Web of Science核心合集数据库中2009至2019年有关血流限制训练的441篇文献进行可视化分析,综合图谱和数据结果,结合关键文献分析研究热点。结果与结论:①血流限制训练研究自21世纪以来呈上升趋势,主要以美国、日本及其机构发表成果较多且影响力较高;②研究主题发展趋势逐渐从对局部组织器官的影响向对身体机能影响发展,从普通人群训练应用向特殊人群干预治疗发展;③热点关键词为血流限制、力量、骨骼肌、肌肥大、生长激素和适应,研究热点主要内容包括不同生理适应机制、训练方法学影响变量、功能障碍人群康复应用及心血管循环功能影响等;④低负荷血流限制训练作为一种运动干预的有效方法,逐渐被应用在骨骼肌肉、心血管、代谢及神经疾病的临床治疗或康复干预中,未来研究可围绕血流限制训练长期运动效益、运动生理适应机制、不同人群应用效果、训练方法安全性等内容发展。
基金Supported by the National Natural Science Foundation of China(Grant No.11561001)the Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(Grant No.NJYT-18-A14)+5 种基金the Natural Science Foundation of Inner Mongolia of China(Grant No.2018MS01026)the Higher School Foundation of Inner Mongolia of China(Grant No.NJZY19211)the Natural Science Foundation of Anhui Provincial Department of Education(Grant No.KJ2018A0833)Provincial Quality Engineering Project of Anhui Colleges and Universities(Grant No.2018mooc608)the Key Cultivated Project at School Level of the National Science Fund of Guangzhou Civil Aviation College(Grant Nos.18X042818X0433)。
文摘Let S_s*be the class of normalized functions f defined in the open unit■such that the quantity zf’(z)/f(z)lies in an eight-shaped region in the right-half plane and satisfies the condition■.In this paper,we aim to investigate Toeplitz determinants for the inverse of this function classes S_s*associated with sine function.
基金the National Natural Science Foundation of China(11401050)Scientific Research Innovation Team Project Affiliated to Yangtze Normal University(2016XJTD01)。
文摘In this paper,we consider the generalized Moser-type inequalities,sayφ(n)≥kπ(n),where k is an integer greater than 1,φ(n)is Euler function andπ(n)is the prime counting function.Using computer,Pierre Dusart’s inequality onπ(n)and Rosser-Schoenfeld’s inequality involvingφ(n),we give all solutions ofφ(n)=2π(n)andφ(n)=3π(n),respectively.Moreover,we obtain the best lower bound that Moser-type inequalitiesφ(n)>kπ(n)hold for k=2,3.As consequences,we show that every even integer greater than 210 is the sum of two coprime composite,every odd integer greater than 175 is the sum of three pairwise coprime odd composite numbers,and every odd integer greater than 53 can be represented as p+x+y,where p is prime,x and y are composite numbers satisfying that p,and x and y are pairwise coprime.Specially,we give a new equivalent form of Strong Goldbach Conjecture.
文摘Extreme values of wind speed were studied based on the highly detailed ERA5 dataset covering the central part of the Kara Sea. Cases in which the ice coverage of the cells exceeded 15% were filtered. Our study shows that the wind speed extrema obtained from station observations, as well as from modelling results in the framework of mesoscale models, can be divided into two groups according to their probability distribution laws. One group is specifically designated as black swans, with the other referred to as dragons (or dragon-kings). In this study we determined that the data of ERA5 accurately described the swans, but did not fully reproduce extrema related to the dragons;these extrema were identified only in half of ERA5 grid points. Weibull probability distribution function (PDF) parameters were identified in only a quarter of the pixels. The parameters were connected almost deterministically. This converted the Weibull function into a one-parameter dependence. It was not clear whether this uniqueness was a consequence of the features of the calculation algorithm used in ERA5, or whether it was a consequence of a relatively small area being considered, which had the same wind regime. Extremes of wind speed arise as mesoscale features and are associated with hydrodynamic features of the wind flow. If the flow was non-geostrophic and if its trajectory had a substantial curvature, then the extreme velocities were distributed according to a rule similar to the Weibull law.
文摘Exponential integral for real arguments is evaluated by employing a fast-converging power series originally developed for the resolution of Grandi’s paradox. Laguerre’s historic solution is first recapitulated and then the new solution method is described in detail. Numerical results obtained from the present series solution are compared with the tabulated values correct to nine decimal places. Finally, comments are made for the further use of the present approach for integrals involving definite functions in denominator.
文摘In this article, we consider the construction of a SVIR (Susceptible, Vaccinated, Infected, Recovered) stochastic compartmental model of measles. We prove that the deterministic solution is asymptotically the average of the stochastic solution in the case of small population size. The choice of this model takes into account the random fluctuations inherent to the epidemiological characteristics of rural populations of Niger, notably a high prevalence of measles in children under 5, coupled with a very low immunization coverage.
基金supported in part by the National Natural Science Foundation of China(61903028,62073030)in part by the China Post-Doctoral Science Foundation(2019M660463)+1 种基金in part by the Fundamental Research Funds for the China Central Universities of University of Science and Technology Beijing(FRF-TP-18-031A1,FRF-BD-19-002A)in part by the Postdoctor Research Foundation of Shunde Graduate School of University of Science and Technology Beijing(2020BH002)。
文摘This paper considers the adaptive neuro-fuzzy control scheme to solve the output tracking problem for a class of strict-feedback nonlinear systems.Both asymmetric output constraints and input saturation are considered.An asymmetric barrier Lyapunov function with time-varying prescribed performance is presented to tackle the output-tracking error constraints.A high-gain observer is employed to relax the requirement of the Lipschitz continuity about the nonlinear dynamics.To avoid the"explosion of complexity",the dynamic surface control(DSC)technique is employed to filter the virtual control signal of each subsystem.To deal with the actuator saturation,an additional auxiliary dynamical system is designed.It is theoretically investigated that the parameter estimation and output tracking error are semi-global uniformly ultimately bounded.Two simulation examples are conducted to verify the presented adaptive fuzzy controller design.
基金This work was supported by the National Natural Science Foundation of China,No.81874032(to GZH)the Science and Technology Planning Project of Shenzhen of China,No.JCYJ20160427191726109(to FZ)+1 种基金the Science and Technology Planning Project of Guangdong Province of China,No.2016A020215202(to SHC)Shenzhen Health and Family Planning System Research Project of China,No.SZXJ2017069(to SHC).
文摘Individuals with amnestic mild cognitive impairment(aMCI)have a high risk of developing Alzheimer’s disease.Although repetitive transcranial magnetic stimulation(rTMS)is considered a potentially effective treatment for cognitive impairment in patients with aMCI,the neuroimaging mechanisms are poorly understood.Therefore,we performed a double-blind randomized sham-controlled trial in which rTMS was applied to the left dorsolateral prefrontal cortex of aMCI patients recruited from a community near the Third Hospital Affiliated to Sun Yat-sen University,China.Twenty-four patients with aMCI were randomly assigned to receive true rTMS(treatment group,n=12,6 men and 6 women;age 65.08±4.89 years)or sham stimulation(sham group,n=12,5 men and 7 women;age 64.67±4.77 years).rTMS parameters included a stimulation frequency of 10 Hz,stimulation duration of 2 seconds,stimulation interval of 8 seconds,20 repetitions at 80%of the motor threshold,and 400 pulses per session.rTMS/sham stimulation was performed five times per week over a period of 4 consecutive weeks.Our results showed that compared with baseline,Montreal Cognitive Assessment scores were significantly increased and the value of the amplitude of low-frequency fluctuation(ALFF)was significantly increased at the end of treatment and 1 month after treatment.Compared with the sham group,the ALFF values in the right inferior frontal gyrus,triangular part of the inferior frontal gyrus,right precuneus,left angular gyrus,and right supramarginal gyrus were significantly increased,and the ALFF values in the right superior frontal gyrus were significantly decreased in the treatment group.These findings suggest that high-frequency rTMS can effectively improve cognitive function in aMCI patients and alter spontaneous brain activity in cognitive-related brain areas.This study was approved by the Ethics Committee of Shenzhen Baoan Hospital of Southern Medical University,China(approval No.BYL20190901)on September 3,2019 and registered in the Chinese Clinical Trials Registry(regi
文摘This paper provides a review of methods of assessing a fragmentation weapon’s effectiveness against a point target or an area target with keeping the focus on the necessity of using the Carleton damage function with the correct shape factor.First,cookie-cutter damage functions are redefined to preserve the shape factor of and to have the same lethal area as the corresponding Carleton damage function.Then,closed-form solutions of the effectiveness methods are obtained by using those cookie-cutter damage functions and the Carleton damage function.Finally,the closed-form solutions are applied to calculate the probability of damaging a point target and the expected fractional damage to an area target for several attack scenarios by using cookie-cutter damage functions and the Carleton damage functions with different shape factors.The comparison of the calculation results shows that using cookie-cutter damage functions or the Carleton damage function with a wrong shape factor results in quite significant differences from using the original Carleton damage function with a correct shape factor when weapon’s delivery error deviations are less than or comparable to the lengths of the lethal area and the aim point is far from a target.The effectiveness methods improved in this paper will be useful for mission planning utilizing the precision-guided munitions in circumstances where the collateral damage should be reduced.
文摘<strong>Background:</strong> Cell replacement therapies have been evaluated in recent years as an alternative for various retinal pathologies to evaluate the therapeutic efficacy of cell therapy, it is important to measure the severity of the disease. The aim of this study was to evaluate the effect of umbilical cord derived Mesenchymal Stem Cell (UC-MSC) implantation on severity of Retinitis Pigmentosa (RP). <strong>Methods:</strong> This single-center, clinical study included data of 138 eyes of 92 patients who had a confirmed diagnosis of RP and received stem cell implantation to the suprachoroidal area with a surgical procedure. Patients were evaluated before and 1 year after the surgery regarding to the outcome measures of Best Corrected Visual Acuity (BCVA), Optical Coherence Tomography (OCT) and Visual Field (VF) tests. BCVA, VF width and ellipsoid zone (EZ) width on OCT were recorded for each patient and a scoring criterion was established for each variable varying from 0 to 5 depending on its distribution. The cumulative score (from 0 to 15) was used to classify disease severity from grade 0 to 5. <strong>Results:</strong> All of the patients completed 12-month follow-up period. The median age of the patients was 40.8 years, 46% were female, 77% had been diagnosed within 10 years and 41% had a family history. 79% of the patients with family history had autosomal recessive inheritance pattern. There were statistically significant improvements in the mean BCVA and VF scores during the study (p < 0.05). The mean score and the mean grade of the disease also improved after the treatment (p < 0.05). There was a negative correlation between BCVA improvement and scoring and grading of the disease. <strong>Conclusions:</strong> This study demonstrated beneficial effect of suprachoroidally applied UC-MSCs on BCVA, VF and the severity score and grade of the disease during 12-month follow-up period. Cell mediated therapy based on the secretion of Growth Factors (GFs) seems to be an effective and safe option for the
文摘The Gauss-linking integral for disjoint oriented smooth closed curves is derived linking integrals from the Biot-Savart description of the magnetic field. DeTurck and Gluck extend this linking from 3-space <em>R</em><sup>3</sup> to <em>SU</em> (2) space of the unit 3-sphere and hyperbolic space in Minkowski <em>R</em><sup>1,3</sup>. I herein extend Gauss-linking to self-linking and develop the concept of self-dual, which is then applied to gravitomagnetic dynamics. My purpose is to redefine Wheeler’s <em>geon</em> from unstable field structures based on the electromagnetic field to self-stabilized gravitomagnetic field structures.
文摘<strong>Background:</strong> <span><span><span style="font-family:""><span style="font-family:Verdana;">Pilates has been shown to be an effective intervention for adults with musculoskeletal conditions with only a few examples available in the li</span><span style="font-family:Verdana;">terature for children. As musculoskeletal pain is a major symptom expe</span><span style="font-family:Verdana;">rienced by children with Hypermobility Spectrum Disorder (HSD), they may benefit from practicing Pilates to improve postural alignment, strength and motor control to effectively distribute movement load and decrease adverse load through involved joints. </span><b><span style="font-family:Verdana;">Method:</span></b><span style="font-family:Verdana;"> This study aims to evaluate the impact of a Physiotherapy-led Pilates intervention on school aged children with HSD and the benefits of this approach on pain, physical function and quality of life when delivered in a community-based model of care. A single-case experimental design (SCED) that incorporates a multiple baseline design will be used. Children with HSD, aged from 8 to 12 years, will commence concurrently in this study. Participants will undergo multiple assessments through all phases of the study which incorporates an A-B-A withdrawal design. The initial baseline period will be randomised from 5 to 7 weeks duration, then participants will enter the intervention period for 8 weeks followed by a withdrawal period of 5 weeks. The Physiotherapy-led Pilates intervention will consist of individual, 45 minute bi-weekly sessions, performed on both mat and the Pilates Reformer with an additional home program of mat exercises performed weekly. The study hypotheses are that children will show: 1) a decrease in pain;2) an increase in their physical function as measured by muscle strength, postural control, fatigue and physical activity levels;and 3) an improvement in their Health Related Quality of Life in the domains of physical, emotional, social and school functioning. </s