Simulation of thermal stress in Er2O3 and Al2O3 tritium penetration barriers by finite-element analysis

The physical vapor deposition method is an effective way to deposit Al2O3 and Er2O3 on 316 L stainless steel substrates acting as tritium permeation barriers in a fusion reactor. The distribution of residual thermal stress is calculated both in Al2O3 and Er2O3 coating systems with planar and rough substrates using finite element analysis. The parameters influencing the thermal stress in the sputter process are analyzed, such as coating and substrate properties, temperature and Young＇s modulus. This work shows that the thermal stress in Al2O3 and Er2O3 coating systems exhibit a linear relationship with substrate thickness, temperature and Young＇s modulus.However, this relationship is inversed with coating thickness. In addition, the rough substrate surface can increase the thermal stress in the process of coating deposition. The adhesive strength between the coating and the substrate is evaluated by the shear stress. Due to the higher compressive shear stress, the Al2O3 coating has a better adhesive strength with a 316 L stainless steel substrate than the Er2O3 coating. Furthermore, the analysis shows that it is a useful way to improve adhesive strength with increasing interface roughness.

Association between intercellular adhesion molecule-1 to depression and blood-brain barrier penetration in cerebellar vascular disease

BACKGROUND Cerebral small vessel disease(CSVD)is a prevalent cerebrovascular disease in clinical practice that is often associated with macrovascular disease.A clear understanding of the underlying causes of CSVD remains elusive.AIM To explore the association between intercellular adhesion molecule-1(ICAM-1)and blood-brain barrier(BBB)penetration in CSVD.METHODS This study included patients admitted to Fuyang People’s Hospital and Fuyang Community(Anhui,China)between December 2021 and March 2022.The study population comprised 142 patients,including 80 in the CSVD group and 62 in the control group.Depression was present in 53 out of 80 patients with CSVD.Multisequence magnetic resonance imaging(MRI)and dynamic contrast-enhanced MRI were applied in patients to determine the brain volume,cortical thickness,and cortical area of each brain region.Moreover,neuropsychological tests including the Hamilton depression scale,mini-mental state examination,and Montreal cognitive assessment basic scores were performed.RESULTS The multivariable analysis showed that age[P=0.011;odds ratio(OR)=0.930,95%confidence interval(CI):0.880-0.983]and ICAM-1 levels(P=0.023;OR=1.007,95%CI:1.001-1.013)were associated with CSVD.Two regions of interest(ROIs;ROI3 and ROI4)in the white matter showed significant(both P<0.001;95%CI:0.419-0.837 and 0.366-0.878)differences between the two groups,whereas only ROI1 in the gray matter showed signi-ficant difference(P=0.046;95%CI:0.007-0.680)between the two groups.ICAM-1 was significantly correlated(all P<0.05)with cortical thickness in multiple brain regions in the CSVD group.CONCLUSION This study revealed that ICAM-1 levels were independently associated with CSVD.ICAM-1 may be associated with cortical thickness in the brain,predominantly in the white matter,and a significant increase in BBB permeability,proposing the involvement of ICAM-1 in BBB destruction.

Study on Physical Basis of Cold Fusion

In order to understand questions about the study on cold fusion in these years, we have studied physical basis of cold fusion. Results show that even though the cold fusion is feasible theoretically in the view of physics, but its reaction ratio is too small to be detected, so that it has no prospect for practical usage at present. However, in order to tackle urgent problem of being poor in energy resources, we have no choice but to pay more attention to controlled thermal nuclear fusion in a considerably long period of time

Carrier-free programmed spherical nucleic acid for effective ischemic stroke therapy via self-delivery antisense oligonucleotide

Antisense oligonucleotide(ASO)for anti-apoptosis is emerging as a highly promising therapeutic agents for ischemic stroke with complex pathological environment.However,its therapeutic efficacy is seriously limited by a number of challenges including inefficient internalization,low blood-brain barrier(BBB)penetration,poor stability,and potential toxicity of the carrier.Herein,a carrier-free programmed spherical nucleic acid nanostructure is developed for effective ischemic stroke therapy via integrating multifunctional modules into one DNA structure.By co-encoding caspase-3-ASO and transferrin receptor(TfR)aptamer into circle template,the spherical nucleic acid nanostructure(TD)was obtained via self-assembly.The experimental results demonstrated that the developed TD displayed efficient BBB penetration capability(6.4 times)and satisfactory caspase-3 silence effect(2.3 times)due to the dense DNA packaging in TD.Taken together,our study demonstrated that the carrier-free programmed spherical nucleic acid nanostructure could significantly improve the therapeutic efficacy of ischemic stroke and was a promising therapeutic tool for various brain damage-related diseases.

Medical micro-and nanomotors in the body

Attributed to the miniaturized body size and active mobility,micro-and nanomotors(MNMs)have demonstrated tremendous potential for medical applications.However,from bench to bedside,massive efforts are needed to address critical issues,such as cost-effective fabrication,on-demand integration of multiple functions,biocompatibility,biodegradability,controlled propulsion and in vivo navigation.Herein,we summarize the advances of biomedical MNMs reported in the past two decades,with particular emphasis on the design,fabrication,propulsion,navigation,and the abilities of biological barriers penetration,biosensing,diagnosis,minimally invasive surgery and targeted cargo delivery.Future perspectives and challenges are discussed as well.This review can lay the foundation for the future direction of medical MNMs,pushing one step forward on the road to achieving practical theranostics using MNMs.