Preparation of Electrode Array by Electrochemical Etching Based on FEM

Process technology of multiple cylindrical micro-pins by wire-electrical discharge machining （wire-EDM） and electrochemical etching was presented. A row of rectangular micro-columns were machined by wire-EDM and then machined into cylindrical shape by electrochemical etching. However, the shape of the multiple electrodes and the consistent sizes of the electrodes row are not easy to be controlled. In the electrochemical process, the shape of the cathode electrode determines the current density distribution on the anode and so the forming of multiple electrodes. This paper proposes a finite element method （FEM） to accurately optimize the electrode profile. The microelectrodes row with uniformity diameters with size from hundreds micrometers to several decades could be fabricated, and mathematical model controlling the shape and diameter of multiple microelectrodes was provided. Furthermore, a good agreement between experimental and theoretical results was confirmed.

Updated Understanding of the Glial-Vascular Unit in Central Nervous System Disorders

The concept of the glial-vascular unit(GVU)was raised recently to emphasize the close associations between brain cells and cerebral vessels,and their coordinated reactions to diverse neurological insults from a“glio-centric”view.GVU is a multicellular structure composed of glial cells,perivascular cells,and perivascular space.Each component is closely linked,collectively forming the GVU.The central roles of glial and perivascular cells and their multi-level interconnections in the GVU under normal conditions and in central nervous system(CNS)disorders have not been elucidated in detail.Here,we comprehensively review the intensive interactions between glial cells and perivascular cells in the niche of perivascular space,which take part in the modulation of cerebral blood flow and angiogenesis,formation of the blood-brain barrier,and clearance of neurotoxic wastes.Next,we discuss dysfunctions of the GVU in various neurological diseases,including ischemic stroke,spinal cord injury,Alzheimer’s disease,and major depression disorder.In addition,we highlight the possible therapies targeting the GVU,which may have potential clinical applications.

Digoxin Ameliorates Glymphatic Transport and Cognitive Impairment in a Mouse Model of Chronic Cerebral Hypoperfusion

The glymphatic system plays a pivotal role in maintaining cerebral homeostasis.Chronic cerebral hypoperfusion,arising from small vessel disease or carotid stenosis,results in cerebrometabolic disturbances ultimately manifesting in white matter injury and cognitive dysfunction.However,whether the glymphatic system serves as a potential therapeutic target for white matter injury and cognitive decline during hypoperfusion remains unknown.Here,we established a mouse model of chronic cerebral hypoperfusion via bilateral common carotid artery stenosis.We found that the hypoperfusion model was associated with significant white matter injury and initial cognitive impairment in conjunction with impaired glym・phatic system function.The glymphatic dysfunction was associated with altered cerebral perfusion and loss of aquaporin 4 polarization.Treatment of digoxin rescued changes in glymphatic transport,white matter structure,and cognitive function.Suppression of glymphatic functions by treatment with the AQP4 inhibitor TGN-020 abolished this protective effect of digoxin from hypoperfusion injury.Our research yields new insight into the relationship between hemodynamics,glymphatic transport,white matter injury,and cognitive changes after chronic cerebral hypoperfusion.

Targeting polarized phenotype of microglia via IL6/JAK2/ STAT3 signaling to reduce NSCLC brain metastasis

Tumor-associated macrophages have emerged as crucial factors for metastases.Microglia are indispensable components of the brain microenvironment and play vital roles in brain metastasis(BM).However,the underlying mechanism of how activated microglia promote brain metastasis of non-small cell lung cancer(NSCLC)remains elusive.

3D multiphysic simulations of energy field and material process in radial ultrasonic rolling electrochemical micromachining

The radial ultrasonic rolling electrochemical micromachining(RUR-EMM)combined rolling electrochemical micromachining(R-EMM)and ultrasonic vibration was studied in this paper.The fundamental understanding of the machining process especially the interaction between multiphysics in the interelectrode gap(IEG)was investigated and discussed by the finite element method.The multiphysics coupling model including flow field model,Joule heating model,material dissolution model and vibration model was built.3D multiphysics simulation based on micro dimples process in RUR-EMM and R-EMM was proposed.Simulation results showed that the electrolyte flowed into and out IEG periodically,gas bubbles were easy to squeeze out and the gas void fraction deceased about 16%to 54%,the maximum current density increased by 1.36 times in RUR-EMM than in R-EMM in one vibration period of time.And application of the ultrasonic vibration increased the electrolyte temperature about 1.3–4.4%in IEG.Verification experiments of the micro dimple process denoted better corrosion consistency of array dimples in RUR-EMM,there was no island at the micro dimple bottom which always formed in R-EMM,and an aggregated deviation of less than 8.7%for the micro dimple depth and 4%for the material removal amount between theory and experiment was obtained.