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Impact of Different Rates of Nitrogen Supplementation on Soil PhysicochemicalProperties and Microbial Diversity in Goji Berry
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作者 Xiaojie Liang Wei An +4 位作者 Yuekun Li Yajun Wang Xiaoya Qin Yanhong Cui Shuchai Su 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期467-486,共20页
Goji berry(Lycium barbarum L.)is substantially dependent on nitrogen fertilizer application,which can signifi-cantly enhance fruit yield and Goji berry industrial development in Ningxia,China.This study aimed to analyz... Goji berry(Lycium barbarum L.)is substantially dependent on nitrogen fertilizer application,which can signifi-cantly enhance fruit yield and Goji berry industrial development in Ningxia,China.This study aimed to analyze the functions of differential nitrogen application rates including low(N1),medium(N2),and high(N3)levels in soil microbial community structure(bacterial and fungal)at 2 diverse soil depths(0-20,20-40 cm)through high-throughput sequencing technology by targeting 16S RNA gene and ITS1&ITS2 regions.All the observed physicochemical parameters exhibited significant improvement(p<0.05)with increased levels of nitrogen and the highest values for most parameters were observed at N2.However,pH decreased(p<0.05)gradually.The alpha and beta diversity analyses for bacterial and fungal communities’metagenome displayed more similarities than differences among all groups.The top bacterial and fungal phyla and genera suggested no obvious(p>0.05)differences among three group treatments(N1,N2,and N3).Furthermore,the functional enrichment analysis demonstrated significant(p<0.05)enrichment of quorum sensing,cysteine and methionine metabolism,and transcriptional machinery for bacterial communities,while various saprotrophic functional roles for fungal communities.Conclusively,moderately reducing the use of N-supplemented fertilizers is conducive to increasing soil nitrogen utilization rate,which can contribute to sustainable agriculture practices through improved soil quality,and microbial community structure and functions. 展开更多
关键词 Goji berry production Ningxia China differential nitrogen supplementation rates 16S RNA gene and IT1&IT2 region sequencing soil physicochemical properties
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The Convergence Rate of Fréchet Distribution under the Second-Order Regular Variation Condition
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作者 Xilai Dai 《Journal of Applied Mathematics and Physics》 2024年第5期1597-1605,共9页
In this article we consider the asymptotic behavior of extreme distribution with the extreme value index γ>0 . The rates of uniform convergence for Fréchet distribution are constructed under the second-order ... In this article we consider the asymptotic behavior of extreme distribution with the extreme value index γ>0 . The rates of uniform convergence for Fréchet distribution are constructed under the second-order regular variation condition. 展开更多
关键词 convergence Rate Second-Order Regular Variation Condition Fréchet Distribution Extreme Value Index
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OPTIMAL CONVERGENCE RATES OF LANDAU EQUATION WITH EXTERNAL FORCING IN THE WHOLE SPACE 被引量:6
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作者 杨彤 喻洪俊 《Acta Mathematica Scientia》 SCIE CSCD 2009年第4期1035-1062,共28页
In this paper, we combine the method of constructing the compensating function introduced by Kawashima and the standard energy method for the study on the Landau equation with external forcing. Both the global existen... In this paper, we combine the method of constructing the compensating function introduced by Kawashima and the standard energy method for the study on the Landau equation with external forcing. Both the global existence of solutions near the time asymptotic states which are local Maxwellians and the optimal convergence rates are obtained. The method used here has its own advantage for this kind of studies because it does not involve the spectrum analysis of the corresponding linearized operator. 展开更多
关键词 compensating function energy method Landau equation optimal convergence rates
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STRONG CONVERGENCE RATES OF SEVERAL ESTIMATORS IN SEMIPARAMETRIC VARYING-COEFFICIENT PARTIALLY LINEAR MODELS 被引量:1
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作者 周勇 尤进红 王晓婧 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1113-1127,共15页
This article is concerned with the estimating problem of semiparametric varyingcoefficient partially linear regression models. By combining the local polynomial and least squares procedures Fan and Huang (2005) prop... This article is concerned with the estimating problem of semiparametric varyingcoefficient partially linear regression models. By combining the local polynomial and least squares procedures Fan and Huang (2005) proposed a profile least squares estimator for the parametric component and established its asymptotic normality. We further show that the profile least squares estimator can achieve the law of iterated logarithm. Moreover, we study the estimators of the functions characterizing the non-linear part as well as the error variance. The strong convergence rate and the law of iterated logarithm are derived for them, respectively. 展开更多
关键词 partially linear regression model varying-coefficient profile leastsquares error variance strong convergence rate law of iterated logarithm
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Some Improvement on Convergence Rates of Kernel Density Estimator 被引量:1
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作者 Xiaoran Xie Jingjing Wu 《Applied Mathematics》 2014年第11期1684-1696,共13页
In this paper two kernel density estimators are introduced and investigated. In order to reduce bias, we intuitively subtract an estimated bias term from ordinary kernel density estimator. The second proposed density ... In this paper two kernel density estimators are introduced and investigated. In order to reduce bias, we intuitively subtract an estimated bias term from ordinary kernel density estimator. The second proposed density estimator is a geometric extrapolation of the first bias reduced estimator. Theoretical properties such as bias, variance and mean squared error are investigated for both estimators. To observe their finite sample performance, a Monte Carlo simulation study based on small to moderately large samples is presented. 展开更多
关键词 KERNEL Density Estimation GEOMETRIC EXTRAPOLATION BIAS Reduction Mean Squared Error convergence Rate
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Strong Convergence Rates of Double Kernel Estimates of Conditional Desity Under Stationary Sequences 被引量:1
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作者 薛留根 李雪臣 马全甫 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第2期1-10, ,共10页
In the paper,we study the strong convergence rates of double kernel estimates of conditional density under stationary sequences.
关键词 conditional density double kernel estimates strong convergence rates stationary sequences
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Inequalities of Maximum of Partial Sums and Convergence Rates in the Strong Laws for ρ^-mixing Random Variables 被引量:1
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作者 TAN Cheng-liang WU Qun-ying HE Yan-mei 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第1期114-119,共6页
In this paper,we establish a Rosenthal-type inequality of partial sums for ρ~mixing random variables.As its applications,we get the complete convergence rates in the strong laws for ρ^-mixing random variables.The re... In this paper,we establish a Rosenthal-type inequality of partial sums for ρ~mixing random variables.As its applications,we get the complete convergence rates in the strong laws for ρ^-mixing random variables.The result obtained extends the corresponding result. 展开更多
关键词 convergence rates rosenthal type inequality ρ—-mixing random variables ρ~mixing random variables negatively associated random variables
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Pearl S. Buck’s Values of “Cultural Convergence” and Their Application
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作者 WANG Yan ZHU Ze-yuan SHI Hui-ge 《Cultural and Religious Studies》 2023年第1期9-18,共10页
The typical features of internal and external integration of cultures as revealed by the conception of“cultural convergence”provide a new perspective on the study of cultural exchanges and mutual learning.In the con... The typical features of internal and external integration of cultures as revealed by the conception of“cultural convergence”provide a new perspective on the study of cultural exchanges and mutual learning.In the context of“a global community of shared future for humankind”,this paper adopts the novel idea of“cultural convergence”to probe the growth of Pearl S.Buck’s cultural values and the specific contents and representation of Pearl S.Buck’s conception of“cultural convergence”,highlighting the application of Pearl S.Buck’s values to cultural education,growth and success,family education,cultural exchanges,humanistic practices,etc.Feasible suggestions and countermeasures are put forward to better promote the cultural exchanges and mutual learning as well as the convergence of different cultures. 展开更多
关键词 Pearl S.Buck values of“cultural convergence applied research
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THE LONG TIME BEHAVIOR OF THE FRACTIONAL ORNSTEIN-UHLENBECK PROCESS WITH LINEAR SELF-REPELLING DRIFT
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作者 夏晓宇 闫理坦 杨晴 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期671-685,共15页
Let B^(H) be a fractional Brownian motion with Hurst index 1/2≤H<1.In this paper,we consider the equation(called the Ornstein-Uhlenbeck process with a linear self-repelling drift)dX_(t)^(H)=dB_(t)^(H)+σ X_(t)^(H)... Let B^(H) be a fractional Brownian motion with Hurst index 1/2≤H<1.In this paper,we consider the equation(called the Ornstein-Uhlenbeck process with a linear self-repelling drift)dX_(t)^(H)=dB_(t)^(H)+σ X_(t)^(H)dt+vdt-θ(∫_(0)^(t)(X_(t)^(H)-X_(s)^(H))ds)dt,whereθ<0,σ,v∈ℝ.The process is an analogue of self-attracting diffusion(Cranston,Le Jan.Math Ann,1995,303:87–93).Our main aim is to study the large time behaviors of the process.We show that the solution X^(H)diverges to infinity as t tends to infinity,and obtain the speed at which the process X^(H)diverges to infinity. 展开更多
关键词 fractional Brownian motion stochastic difference equations rate of convergence ASYMPTOTIC
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Higher-order expansions of powered extremes of logarithmic general error distribution
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作者 TAN Xiao-feng LI Li-hui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期47-54,共8页
In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥1.Higher-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of nor... In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥1.Higher-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of normalizing constants.It is shown that M_(n)^(p),when v=1,converges to the Frechet extreme value distribution at the rate of 1/n,and if v>1 then M_(n)^(p)converges to the Gumbel extreme value distribution at the rate of(loglogn)^(2)=(log n)^(1-1/v). 展开更多
关键词 logarithmic general error distribution convergence rate higher-order expansion powered ex-treme
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Seasonal Variation of the Sea Surface Temperature Growth Rate of ENSO
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作者 Xinyi XING Xianghui FANG +1 位作者 Da PANG Chaopeng JI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期465-477,共13页
El Ni?o–Southern Oscillation(ENSO) exhibits a distinctive phase-locking characteristic, first expressed during its onset in boreal spring, developing during summer and autumn, reaching its peak towards winter, and de... El Ni?o–Southern Oscillation(ENSO) exhibits a distinctive phase-locking characteristic, first expressed during its onset in boreal spring, developing during summer and autumn, reaching its peak towards winter, and decaying over the next spring. Several studies have demonstrated that this feature arises as a result of seasonal variation in the growth rate of ENSO as expressed by the sea surface temperature(SST). The bias towards simulating the phase locking of ENSO by many state-of-the-art climate models is also attributed to the unrealistic depiction of the growth rate. In this study, the seasonal variation of SST growth rate in the Ni?o-3.4 region(5°S–5°N, 120°–170°W) is estimated in detail based on the mixed layer heat budget equation and recharge oscillator model during 1981–2020. It is suggested that the consideration of a variable mixed layer depth is essential to its diagnostic process. The estimated growth rate has a remarkable seasonal cycle with minimum rates occurring in spring and maximum rates evident in autumn. More specifically, the growth rate derived from the meridional advection(surface heat flux) is positive(negative) throughout the year. Vertical diffusion generally makes a negative contribution to the evolution of growth rate and the magnitude of vertical entrainment represents the smallest contributor. Analysis indicates that the zonal advective feedback is regulated by the meridional immigration of the intertropical convergence zone, which approaches its southernmost extent in February and progresses to its northernmost location in September, and dominates the seasonal variation of the SST growth rate. 展开更多
关键词 SST growth rate intertropical convergence zone zonal advective feedback mixed layer depth ENSO seasonal variation
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SUBGEOMETRIC RATES OF CONVERGENCE OF THE GI/G/1 QUEUEING SYSTEM
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作者 李晓花 侯振挺 《Acta Mathematica Scientia》 SCIE CSCD 2012年第5期1983-1996,共14页
The article deals with the waiting time process of the GI/G/1 queueing system.We shall give that the rate of convergence to the stationary distribution and the decay of the stationary tail only depend on the tail of t... The article deals with the waiting time process of the GI/G/1 queueing system.We shall give that the rate of convergence to the stationary distribution and the decay of the stationary tail only depend on the tail of the service distribution,but not on the interarrival distribution.We shall also give explicit criteria for the rate of convergence and decay of stationary tail for three specific types of subgeometric cases(Case 1:the rate function r(n)=exp(sn1/1+α),α〉0,s〉0;Case 2:polynomial rate function r(n)=nα,α〉0;Case 3:logarithmic rate function r(n)=logαn,α〉0). 展开更多
关键词 GI/G/1 queueing system subgeometric rate of convergence polynomial rate of convergence logarithmic rate of convergence
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CONVERGENCE RATES FOR A CLASS OF EVOLUTIONARY ALGORITHMS WITH ELITIST STRATEGY
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作者 丁立新 康立山 《Acta Mathematica Scientia》 SCIE CSCD 2001年第4期531-540,共10页
This paper discusses the convergence rates about a class of evolutionary algorithms in general search spaces by means of the ergodic theory in Markov chain and some techniques in Banach algebra. Under certain conditio... This paper discusses the convergence rates about a class of evolutionary algorithms in general search spaces by means of the ergodic theory in Markov chain and some techniques in Banach algebra. Under certain conditions that transition probability functions of Markov chains corresponding to evolutionary algorithms satisfy, the authors obtain the convergence rates of the exponential order. Furthermore, they also analyze the characteristics of the conditions which can be met by genetic operators and selection strategies. 展开更多
关键词 convergence rate Markov chain Banach algebra genetic operator elitist selection evolutionary algorithms
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GLOBAL EXISTENCE AND CONVERGENCE RATES OF SMOOTH SOLUTIONS FOR THE 3-D COMPRESSIBLE MAGNETOHYDRODYNAMIC EQUATIONS WITHOUT HEAT CONDUCTIVITY
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作者 高真圣 谭忠 吴国春 《Acta Mathematica Scientia》 SCIE CSCD 2014年第1期93-106,共14页
In this paper, we are concerned with the global existence and convergence rates of the smooth solutions for the compressible magnetohydrodynamic equations without heat conductivity, which is a hyperbolic-parabolic sys... In this paper, we are concerned with the global existence and convergence rates of the smooth solutions for the compressible magnetohydrodynamic equations without heat conductivity, which is a hyperbolic-parabolic system. The global solutions are obtained by combining the local existence and a priori estimates if H3-norm of the initial perturbation around a constant states is small enough and its L1-norm is bounded. A priori decay-in-time estimates on the pressure, velocity and magnetic field are used to get the uniform bound of entropy. Moreover, the optimal convergence rates are also obtained. 展开更多
关键词 MAGNETOHYDRODYNAMICS optimal convergence rate decay-in-time estimates
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CONVERGENCE RATES IN THE LAW OF LARGE NUMBERS FOR B-VALUED RANDOM ELEMENTS
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作者 梁汉营 王丽 《Acta Mathematica Scientia》 SCIE CSCD 2001年第2期229-236,共8页
The author discusses necessary and sufficient conditions of the complete con- vergence for sums of B-valued independent but not necessarily identically distributed r.v.'s in Banach space of type p, and obtains cha... The author discusses necessary and sufficient conditions of the complete con- vergence for sums of B-valued independent but not necessarily identically distributed r.v.'s in Banach space of type p, and obtains characterization of Banach space of type p in terms of the complete convergence. A series of classical results on iid real valued r.v.'s are ex- tended. As application authors give the analogous results for randomly indexed sums. 展开更多
关键词 convergence rate random element Banach space of type p slowly varying function
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ON THE RATES OF CONVERGENCE IN THE CENTRAL LIMIT THEOREM FOR TWO-PARAMETER MARTINGALE DIFFERENCES
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作者 龙红卫 《Acta Mathematica Scientia》 SCIE CSCD 1996年第3期287-295,共9页
In this paper we obtain the uniform bounds on the rate of convergence in the central limit theorem (CLT) for a class of two-parameter martingale difference sequences under certain conditions.
关键词 noncomplete half-plane martingale difference central limit theorem rates of convergence uniform bound
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Convergence Rates of Density Estimation in Besov Spaces
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作者 Huiying Wang 《Applied Mathematics》 2011年第10期1258-1262,共5页
The optimality of a density estimation on Besov spaces Bsr,q(R) for the Lp risk was established by Donoho, Johnstone, Kerkyacharian and Picard (“Density estimation by wavelet thresholding,” The Annals of Statistics,... The optimality of a density estimation on Besov spaces Bsr,q(R) for the Lp risk was established by Donoho, Johnstone, Kerkyacharian and Picard (“Density estimation by wavelet thresholding,” The Annals of Statistics, Vol. 24, No. 2, 1996, pp. 508-539.). To show the lower bound of optimal rates of convergence Rn(Bsr,q, p), they use Korostelev and Assouad lemmas. However, the conditions of those two lemmas are difficult to be verified. This paper aims to give another proof for that bound by using Fano’s Lemma, which looks a little simpler. In addition, our method can be used in many other statistical models for lower bounds of estimations. 展开更多
关键词 Optimal Rate of convergence Density Estimation BESOV SPACES WAVELETS
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CONVERGENCE RATE FOR ITERATES OF q-BERNSTEIN POLYNOMIALS
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作者 Xueyan Xiang Qian He Wenshan Yang 《Analysis in Theory and Applications》 2007年第3期243-254,共12页
Recently, q-Bernstein polynomials have been intensively investigated by a number of authors. Their results show that for q ≠ 1, q-Bernstein polynomials possess of many interesting properties. In this paper, the conve... Recently, q-Bernstein polynomials have been intensively investigated by a number of authors. Their results show that for q ≠ 1, q-Bernstein polynomials possess of many interesting properties. In this paper, the convergence rate for iterates of both q-Bernstein polynomials and their Boolean sum are estimated. Moreover, the saturation of {Bn(., qn)} when n → ∞ and convergence rate of Bn(f,q;x) when f ∈ C^n-1 [0, 1], q → ∞ are also presented. 展开更多
关键词 q-Bernstein operator convergence rate saturation of positive lienar operator iterates
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A Comprehensive Analysis of Efficacy and Safety of Probiotics in Inflammatory Bowel Disease
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作者 Feruza Abraamyan Neeladri Misra 《Open Journal of Gastroenterology》 CAS 2024年第6期213-225,共13页
Introduction: Inflammatory bowel disease (IBD) affects approximately 7 million people worldwide. In the U.S. alone, per the CDC, 1.3% of adults, which is approximately 3,000,000 people, are diagnosed with inflammatory... Introduction: Inflammatory bowel disease (IBD) affects approximately 7 million people worldwide. In the U.S. alone, per the CDC, 1.3% of adults, which is approximately 3,000,000 people, are diagnosed with inflammatory bowel disease-either, Crohn’s disease, or ulcerative colitis. The estimated cost of treatment can be close to $23,000 annually, with treatment regimens comprising biologic agents and anti-inflammatory therapies. Probiotics have recently gathered interest as a low-cost additional therapy option that, in addition to the current regimen of IBD management, allows for reductions in rates of IBD flare-ups by significantly reducing the number of emergency room visits and avoiding the need to constantly escalate treatment by addition of biologic agents in achieving remission. The Analysis Goal: Our research project aimed to see if there was a significant difference in the addition of probiotics to standard therapy in inflammatory bowel disease by comparing existing research studies and trials. We analyzed RCTs published in PubMed to assess the efficacy and safety of probiotics in patients with IBD in preventing frequent disease flare-ups and reducing the cost of care. Research Methods: We did a comparative analysis of available RCTs using a PubMed search and included studies that researched the addition of probiotic strains in patients with IBD (ulcerative colitis and Crohn’s disease). After reviewing the inclusion and exclusion criteria, the trials selected for analysis were reviewed by two independent reviewers. Results: We analyzed 21 RCTs, and 16 RCTs (76.2%) showed that probiotics are an effective therapy for IBD, inducing remission and reducing flare-up rates in patients on a standard treatment regimen. Conclusion: Probiotics given in combination with standard therapy in IBD are effective in decreasing disease activity rates and reducing remission rates. No significant adverse reactions to probiotics were noticed. 展开更多
关键词 PROBIOTICS Inflammatory Bowel Disease Crohn’s Disease Ulcerative Colitis Remission rates
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Design of a Biomedical Device to Reduce Anxiety Experienced by Patients Diagnosed with Parkinson’s Disease
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作者 Madhini Vigneswaran Anjali Menon 《Journal of Biomedical Science and Engineering》 2024年第3期57-71,共15页
Parkinson’s disease (PD) is a neurodegenerative disease that occurs due to loss of nerve cells that produce dopamine in the brain, affecting approximately 4 million people worldwide. PD patients often feel an increas... Parkinson’s disease (PD) is a neurodegenerative disease that occurs due to loss of nerve cells that produce dopamine in the brain, affecting approximately 4 million people worldwide. PD patients often feel an increase in anxiety levels daily. While there are medications/exercises to help relieve anxiety, there are limited methods to reduce anxiety without the help of a caretaker. As a result, MEDIC Foundation, a non-profit organization in British Columbia, Canada, is designing an automated system that consists of a wristband and an application which uses vi-bration therapy to help reduce anxiety of PD patients. Literature reviews were conducted to document the project’s needs. Phase I of the project focused on de-veloping a prototype for the application and phase II on developing the wrist-band. The team developed prototypes of a wristband that automatically applies vibration near the median nerve as the heart rate variability (HRV) deviates away from the normal threshold of the user, and an application that displays real-time heart rate variability signals as well as provides for relaxation. The development of the prototype is still in early progress. By creating this automated system, we aim to provide a solution to senior PD patients to relieve anxiety independently. . 展开更多
关键词 Vibration Therapy Healthcare Application Parkinson’s Disease ANXIETY WRISTBAND Heart Rate Variability
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