Transcranial Direct Current Stimulation: Effects on Motor and Non-Motor Symptoms of Parkinson’s Disease

Introduction: In the last thirty years, brain neuromodulation techniques have been used as an alternative to pharmacological treatment of neurological disorders. Parkinson’s disease (PD) is a neurodegenerative disorder leading to bradykinesia, rest tremor, postural changes, and non-motor symptoms such as depression, anxiety, sleep disorders, pain, and cognitive decline that compromises executive functions (EFs), responsible for the orderly execution of behaviors and tasks of daily life and intentional and directed actions. To this date, a few studies with transcranial direct current stimulation (tDCS) have shown beneficial effects in PD patients concerning specific motor and non-motor symptoms, targeting the motor cortex and/or prefrontal regions. Objective: The main objective of this study was to evaluate the effects of left prefrontal tDCS across a broad spectrum of motor and non-motor symptoms of PD using established validated scales. Method: Single-blind randomized clinical trial with 18 volunteers with PD, aged between 45 and 80 years (66.1 ± 9.65), who met inclusion and exclusion criteria. Participants were submitted to assessments of motor and non-motor functions employing psychometric scales and tests to evaluate EFs and were randomly divided into two groups: control (sham stimulation) and experimental (active stimulation). All participants were involved in three separate tDCS sessions. The anode was positioned over the left dorsolateral prefrontal cortex and the cathode over the right supraorbital region, with a direct current intensity of 2 mA, lasting 20 minutes. At the end of the three sessions, all participants were reassessed. Results: Significant effects of tDCS on non-motor functions were observed for cognition (verbal fluency of actions, clock copy test, appointment by visual confrontation, and verbal memory with immediate free recall) and subjective assessment of sleep quality (overall restlessness and discomfort in the arms and legs at night, leg and arm cramps at night and distressing dreams). There was also an improvement in the rate of errors and successes for congruent and incongruent stimuli of the Stroop Test. The beneficial effects on motor function were decreased rigidity, improved gait, and greater agility in the finger-tapping test. Conclusion: Three tDCS sessions showed positive results for participants with PD, producing significant improvements in various motor and non-motor functions, including sleep quality, cognition, and EFs. Additionally, the present results indicate that tDCS neuromodulation of the left dorsolateral prefrontal cortex region is feasible, safe, and provides significant objective benefits for PD patients.

Cell reprogramming therapy for Parkinson’s disease

Parkinson’s disease is typically characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta.Many studies have been performed based on the supplementation of lost dopaminergic neurons to treat Parkinson’s disease.The initial strategy for cell replacement therapy used human fetal ventral midbrain and human embryonic stem cells to treat Parkinson’s disease,which could substantially alleviate the symptoms of Parkinson’s disease in clinical practice.However,ethical issues and tumor formation were limitations of its clinical application.Induced pluripotent stem cells can be acquired without sacrificing human embryos,which eliminates the huge ethical barriers of human stem cell therapy.Another widely considered neuronal regeneration strategy is to directly reprogram fibroblasts and astrocytes into neurons,without the need for intermediate proliferation states,thus avoiding issues of immune rejection and tumor formation.Both induced pluripotent stem cells and direct reprogramming of lineage cells have shown promising results in the treatment of Parkinson’s disease.However,there are also ethical concerns and the risk of tumor formation that need to be addressed.This review highlights the current application status of cell reprogramming in the treatment of Parkinson’s disease,focusing on the use of induced pluripotent stem cells in cell replacement therapy,including preclinical animal models and progress in clinical research.The review also discusses the advancements in direct reprogramming of lineage cells in the treatment of Parkinson’s disease,as well as the controversy surrounding in vivo reprogramming.These findings suggest that cell reprogramming may hold great promise as a potential strategy for treating Parkinson’s disease.

Recording the direct surgeon’s view with an operating microscopic view improves microscopic ophthalmic surgery training

AIM:To establish a recording system with a direct view of the surgeon to supplement video recording under an operating microscope,which lacks information on the movement and position of the surgeon’s hands,and to facilitate the reproduction of a skilled surgeon’s technique by a surgeon in training.METHODS:A small camera was attached to the operating microscope with a custom adapter.Microscopic surgeon’s view and direct surgeon’s view through this new camera were recorded in the surgical recording system.Both movies were synchronized and analyzed how do surgeons handle the instruments.RESULTS:A small camera attached to the operating microscope allowed the surgeon’s hands motion to be recorded without interfering with the surgeon’s movements.Different surgeons used different methods to manipulate the ultrasound handpiece and the irrigation/aspiration device.Even in the simple paracentesis procedure,different surgeons used different methods.Surgeons-in-training were able to identify and improve their weaknesses by watching synchronized movies of their hand motions and microscopic view.CONCLUSION:Simultaneous recording the surgical field out of the operating microscopic view by a small camera set on the microscope is comprehensive and improves surgeons-in-training understanding and learning surgeries.

Combinations of Right Half-Plane Mappings and Vertical Strip Mappings Convex in the Vertical Direction

In this paper, we explore the linear combinations of right half-plane mappings and vertical strip mappings. We demonstrate that the combinations of these harmonic mappings are convex in the vertical direction provided they are locally univalent and sense-preserving. Furthermore, we extend this analysis to a more general case by setting specific conditions. Additionally, we take some common parameters such as as the dilatation of these harmonic mappings, and prove the sufficient conditions that their combinations are locally univalent and convex in the vertical direction. Several examples are constructed by the Mathematica software to demonstrate our main results.

基于激光吸收光谱的CO/CO_(2)/H_(2)S浓度同步在线测量研究

CO、CO_(2)、H_(2)S是燃煤锅炉炉内气氛重要组成部分,其浓度不仅能够反映燃烧工况,还可作为水冷壁高温腐蚀程度判断依据,因此实现CO、CO_(2)、H_(2)S浓度的准确测量意义重大。首先采用波长调制-直接吸收(WM-DAS)方法结合约40 m长光程Herriott池,在室温低压下,开展不同CO/CO_(2)浓度配比下三种气体吸收率同步测量实验,结果表明三种气体的吸收率测量值与理论计算值相近,相对误差在6.82%以内,测量结果可靠性较高;然后对不同浓度CO/CO_(2)(0~2000μL·L^(-1))、H_(2)S(0~20μL·L^(-1))进行动态测量,结果表明,测量系统对三种组分浓度变化的响应具有较好的线性度。

EXPERIMENTAL RESEARCH ON DIRECTIONAL SOLIDIFICATION OF Al－4．5wt％Cu ALLOY BY ACRT METHOD

Accelerated crucible rotation technique(ACRT) has been used for the directional solidification of Al-4.5wt% Cu binary alloy.By rotating the crucible at varying rate and direction,forced liquid flows are aroused These flows include Ekman flow,Couette flow and Spiral Shear flow.Especially,Ekman flow acts directly at the L/S interface,changes diffusion and heat exchange conditions and has strong influences on the morphology of L/S interface.Experimental results show that,compared with normal Bridgman specimens,the solidification region is much narrower and the cell spacing is much smaller in ACRT specimens.These influences become much stronger when the accelerating rate is increased.

基于DirectShow的网络视频点播系统的设计与实现

随着计算机技术和Internet日新月异的的发展,宽带VOD视频点播技术因其良好的人机交互性和流媒体传输技术倍受教育、娱乐等行业的青睐。设计了一种基于Direct Show技术的视频点播系统,该系统采用VC编程语言实现,基于C/S架构搭建通信网络,通过套接字实现多台客户机与服务器间的通信。测试结果表明,系统能够正常运行,视频播放流畅,可以满足网络视频点播的需求。

Revised quantum direct communication scheme with mutual authentication

Based on mutual authentication and dense coding,a novel revised efficient quantum direct communication scheme is proposed.It is composed of two phases：the quantum state distribution process and the direct communication process.The purpose of the former is to authenticate Trent and users to each other,and let the two legitimate users（Alice and Bob）safely share the Bell states.While the latter aims to make direct communication to transmit a secret message between Alice and Bob.In order to prevent from Eve＇s eavesdropping as well as to authenticate each other simultaneously,a decoy photon checking technique is applied.Compared with other analogous protocols,the quantum state distribution process is more simple and feasible and the proposed scheme is more efficient;i.e.,the total efficiency is almost 100%.Security analysis shows that the proposed scheme is secure against the eavesdropping attacks,the impersonation attacks,and some special Trent＇s attacks,including the attacks by using different initial states.

四川地区场地放大系数特征分析及在强地震动模拟中的应用——以2022年芦山M_(S)6.1地震为例

基于四川地区62个强震动台站的场地资料,依据中国抗震规范及美国下一代衰减的Geomatrix(GMX)场地分类方法将台站场地进行了划分,并以台站的场地放大系数和高频衰减参数(κ0)为基础数据,研究了不同场地类型的场地放大系数平均特征.结果显示,在中国Ⅱ类场地中,受狭窄山间谷底地形效应影响,满足GMX的C类场地在大于10 Hz的高频段有明显放大;受深厚软弱沉积层影响,满足GMX的D类场地在小于5 Hz的低频段放大效应显著.考虑震源滑动模型、山区和盆地品质因子差异、局部场地效应,采用区域内余震平均应力降,通过随机有限断层法模拟了2022年芦山M_(S)6.1地震中9个断层距(Rrup)<100 km的强震动台站的加速度时程、傅里叶振幅谱(FAS)和反应谱(PSA).结果显示,模拟结果与观测加速度时程的S波部分符合良好.在8 s以下周期范围内模拟与观测FAS和PSA形状和幅值基本一致.较好地模拟结果支持此次地震为2013年芦山M_(S)7.0芦山地震的一次余震.另外,模拟结果体现了此次地震在Rrup<35 km范围内有明显的方向性效应,与观测数据相符.最后,考虑各类场地的场地放大系数和κ0的平均特性,比较了此次地震中Rrup<150 km的167个盆地和130个山区烈度台观测和模拟峰值加速度(PGA)和峰值速度(PGV),以及周期为0.5 s、1.0 s、5.0 s和8.0 s的PSA幅值随断层距的衰减特性.结果显示,山区和盆地的地震动参数随距离的衰减特性较为相似,山区和盆地的PGA、PGV强度相当.但是,在周期大于1.0 s的长周期段,盆地的反应谱幅值整体上大于山区.

一种S频段反射型可调模拟移相器的设计

设计了一种应用于S频段卫星通信相控阵系统的反射型可调模拟移相器。该移相器利用三分支线定向耦合器扩展了带宽,改善了工作频段内驻波;采用传输线和变容二极管构成的L型反射负载扩大了相移量。测试结果表明,在上行频段1.98~2.01 GHz内,相移量达到191°±1°,在下行频段2.17~2.2 GHz内,相移量达到186°±0.1°;插入损耗优于3.3 dB且插入损耗波动小于1 dB,回波损耗在整个电压调谐范围内均大于20 dB。该移相器结构简单、便于调节且价格低廉,在卫星通信领域有一定的应用价值。

ON THE EXISTENCE OF SINGULAR DIRECTIONS OF HOLOMORPHIC MAPS FROM THE UNIT DISK INTO P^n(C)

This article proves the existence of Julia directions of value distribution of holomorphic mapping f from the unit disk into the n-dimensional complex projective spacePn（C） under the assumption limsupT（r,f）/log 1/1-r = ＋∞ for hypersurfaces in general position. A heuristic principle concerning the existence of Julia directions of holomorphic mappings from the unit disk into Pn（C） is given also.

Global Inverse Optimal Tracking Control of Underactuated Omni-directional Intelligent Navigators （ODINs）

This paper presents a design of optimal controllers with respect to a meaningful cost function to force an underactuated omni-directional intelligent navigator （ODIN） under unknown constant environmental loads to track a reference trajectory in two-dimensional space. Motivated by the vehicle＇s steering practice, the yaw angle regarded as a virtual control plus the surge thrust force are used to force the position of the vehicle to globally track its reference trajectory. The control design is based on several recent results developed for inverse optimal control and stability analysis of nonlinear systems, a new design of bounded disturbance observers, and backstepping and Lyapunov＇s direct methods. Both state- and output-feedback control designs are addressed. Simulations are included to illustrate the effectiveness of the proposed results.

BOREL'S DIRECTIONS AND SHARED VALUES

In this article, we study the problems of Borel＇s directions of meromorphic func- tions concerning shared values and prove that if two meromorphie functions of infinite order share three distinct values, their Borel＇s directions are same.

A direct probabilistic approach to solve state equations for nonlinear systems under random excitation

In this paper, a direct probabilistic approach（DPA） is presented to formulate and solve moment equations for nonlinear systems excited by environmental loads that can be either a stationary or nonstationary random process.The proposed method has the advantage of obtaining the response＇s moments directly from the initial conditions and statistical characteristics of the corresponding external excitations. First, the response＇s moment equations are directly derived based on a DPA, which is completely independent of the It？/filtering approach since no specific assumptions regarding the correlation structure of excitation are made.By solving them under Gaussian closure, the response＇s moments can be obtained. Subsequently, a multiscale algorithm for the numerical solution of moment equations is exploited to improve computational efficiency and avoid much wall-clock time. Finally, a comparison of the results with Monte Carlo（MC） simulation gives good agreement.Furthermore, the advantage of the multiscale algorithm in terms of efficiency is also demonstrated by an engineering example.

Anodal transcranial direct current stimulation alleviates cognitive impairment in an APP/PS1 model of Alzheimer’s disease in the preclinical stage

Anodal transcranial direct current stimulation(AtDCS)has been shown to alleviate cognitive impairment in an APP/PS1 model of Alzheimer’s disease in the preclinical stage.However,this enhancement was only observed immediately after AtDCS,and the long-term effect of AtDCS remains unknown.In this study,we treated 26-week-old mouse models of Alzheimer’s disease in the preclinical stage with 10 AtDCS sessions or sham stimulation.The Morris water maze,novel object recognition task,and novel object location test were implemented to evaluate spatial learning memory and recognition memory of mice.Western blotting was used to detect the relevant protein content.Morphological changes were observed using immunohistochemistry and immunofluorescence staining.Six weeks after treatment,the mice subjected to AtDCS sessions had a shorter escape latency,a shorter path length,more platform area crossings,and spent more time in the target quadrant than sham-stimulated mice.The mice subjected to AtDCS sessions also performed better in the novel object recognition and novel object location tests than sham-stimulated mice.Furthermore,AtDCS reduced the levels of amyloid-β42 and glial fibrillary acidic protein,a marker of astrocyte activation,and increased the level of neuronal marker NeuN in hippocampal tissue.These findings suggest that AtDCS can improve the spatial learning and memory abilities and pathological state of an APP/PS1 mouse model of Alzheimer’s disease in the preclinical stage,with improvements that last for at least 6 weeks.

Does Foreign Direct Investment Affect S0_(2) Emissions in the Yangtze River Delta?A Spatial Econometric Analysis

As the major source of air pollution,sulfur dioxide(S0_(2))emissions have become the focus of global attention.However,existing studies rarely consider spatial effects when discussing the relationship between foreign direct investment(FDI)and S0_(2) emissions.This study took the Yangtze River Delta as the research area and used the spatial panel data of 26 cities in this region for 2004-2017.The study investigated the spatial agglomeration effects and dynamics at work in FDI and S0_(2) emissions by using global and local measures of spatial autocorrelation.Then,based on regression analysis using a results of traditional ordinary least squares(OLS)model and a spatial econometric model,the spatial Durbin model(SDM)with spatial-time effects was adopted to quantify the impact of FDI on S0_(2) emissions,so as to avoid the regression results bias caused by ignoring the spatial effects.The results revealed a significant spatial autocorrelation between FDI and S0_(2) emissions,both of which displayed obvious path dependence characteristics in their geographical distribution.A series of agglomeration regions were observed on the spatial scale.The estimation results of the SDM showed that FDI inflow promoted S0_(2) emissions,which supports the pollution haven hypothesis.The findings of this study are significant in the prevention and control of air pollution in the Yangtze River Delta.

ON A NEW SINGULAR DIRECTION OF QUASIMEROMORPHIC MAPPINGS

By applying Ahlfors＇ theory of covering surface, we establish a fundamental inequality for quasimeromorphic mapping in an angular domain. As an application, we prove the existence of a new singular direction for quasimeromorphic mapping f, namely, a precise S direction, for which the spherical characteristic function S（r, f） is used as a comparison function.

DFT Study on the (S)-Proline-catalyzed Direct Aldol Reaction between Acetone and 4-Nitrobenzaldehyde

DFT/6-31G^＊ calculations were applied to study the direct aldol reaction between acetone and 4-nitrobenzaldehyde catalyzed by （S）-proline. Four transition states associated with the stereo-controlling step, corresponding to syn and anti arrangements of methylene moiety related to the carboxylic acid group in enamine intermediate and re and si attacks to the aldehyde carbonyl carbon have been obtained. The solvent effect of DMSO was investigated with polarized continuum model. The computed energies of transition states reveal the stereo-selectivity of the reaction.

Symmetry and Exact Solutions of (2+1)-Dimensional Generalized Sasa-Satsuma Equation via a Modified Direct Method

In this paper, first, we employ classic Lie symmetry groups approach to obtain the Lie symmetry groupsof the well-known (2+1)-dimensional Generalized Sasa-Satsuma (GSS) equation. Second, based on a modified directmethod proposed by Lou [J. Phys. A: Math. Gen. 38 (2005) L129], more general symmetry groups are obtained andthe relationship between the new solution and known solution is set up. At the same time, the Lie symmetry groupsobtained are only special cases of the more general symmetry groups. At last, some exact solutions of GSS equationsare constructed by the relationship obtained in the paper between the new solution and known solution.

Rays’ Change of Directions between Inertial Frames and Stellar Aberration

The path of a light’s signal is one and the same in the universal space regardless of the inertial frame by which it is identified. However, only one frame can be taken stationary and identified with the universal space while all other frames are moving. The direction of the path of a light’s pulse in a moving frame is determined in terms of its direction in the stationary one;the result is utilized to explain stellar aberration and show that the tilted direction in the moving frame depends only on its velocity. The aberration increment vector is introduced and employed to determine the apparent position of a star at each point of the earth orbit. Aberration in an earth satellite relative to the geocentric frame is presented. The direction’s change of a light beam between graded inertial frames promotes explaining aberration in an earth’s satellite in parallel to stellar aberration on earth.