Interfacial microstructure and shear strength of Ti-6Al-4V/TiAl laminate composite sheet fabricated by hot packed rolling

A two layer Ti-6Al-4V(wt%)/Ti-43Al-9V-Y(at%) laminate composite sheet with a uniform interfacial microstructure and no discernible defects at the interfaces has been prepared by hot-pack rolling, and its interfacial microstructure and shear strength were characterized. Characterization of the interfacial microstructure shows that there was an interfacial region of uniform thickness of about 250 μm which consisted of two layers: Layer I on the TiAl side which was 80 μm thick and Layer II on the Ti-6Al-4V side which was 170 μm thick. The microstructure of Layer I consisted of massive γ phases, needlelike γ phases and B2 phase matrix, while the microstructure of Layer II consisted of α₂ phase. The microstructure of the interfacial region is the result of the interdiffusion of Ti element from Ti-6Al-4V alloy layer into the TiAl alloy layer and Al element from the TiAl alloy layer into the Ti-6Al-4V alloy layer. The shear strength measurement demonstrated that the bonding strength between the TiAl alloy and Ti-6Al-4V alloy layers in the laminate composite sheet was very high. This means that the quality of the interfacial bonding between the two layers achieved by the multi-path rolling is high, and the interface between the layers is very effective in transferring loading, causing significantly improved toughness and plasticity of the TiAl/Ti-6Al-4V laminate composite sheet

Microstructure and mechanical properties of large size as-cast Ti-43Al-9V-0.2Y (at.%) alloy ingot from brim to centre

A Ti-43Al-9V-0.2Y (at.%) alloy ingot with the size of Ф160×400mm was prepared by vacuum arc remelting (VAR). The microstructure of the as-cast Ti-43Al-9V-0.2Y alloy was composed of B2/α₂/γ lamellar colonies and massive B2 and γ phases which were distributed along the boundaries of these lamellar colonies in the form of equiaxed grains. Based on the grain size variation along the radius direction of the ingot, the ingot could be divided into four ring regions from brim to centre. It has been understood that the grain size variation between these four regions was due to the interplay of the effects of the cooling rate and the yttrium content on solidified microstructures in these regions. Mechanical testing of the samples cut from these four regions showed that there existed a clear correlation between the yield strength and the average grain sizes of the four ring regions, which approximately conformed to a Hall-Petch relationship

Investigations into the Rock Dynamic Response under Blasting Load by an Improved DDA Approach

Evaluation of blasting-induced rock damage and fragmentation is very important for safety control of construction in the jointed rock mass. The discontinuous numerical models are commonly applied due to the advantages in modeling fragmentation and treating discontinuities. In this paper, the rock fracturing algorithm and rate dependent strength law are incorporated into the discontinuous deformation analysis (DDA) to study the wave propagation and rock fragmentation phenomena in dynamic problems. By reproducing Hopkinson pressure bar tests under different loading rates, the improved method is validated to be capable of solving dynamic failure problem. Finally, taking the Xiucun tunnel as an example, its failure process under the action of the explosive wave is simulated, and some failure features are captured. In addition, the explosion wave propagation and its induced particle vibration in surrounding rock are studied. The reasonable simulation results indicate that the modified DDA method can effectively model the stress wave propagation and joint growth process in the jointed rock under blasting load. © 2021 Biting Xie et al

Role of Selective Histone Deacetylase 6 Inhibitor ACY-1215 in Cancer and Other Human Diseases

The deacetylation process regulated by histone deacetylases (HDACs) plays an important role in human health and diseases. HDAC6 belongs to the Class IIb of HDACs family, which mainly modifies non-histone proteins located in the cytoplasm. HDAC6 plays a key role in tumors, neurological diseases, and inflammatory diseases. Therefore, targeting HDAC6 has become a promising treatment strategy in recent years. ACY-1215 is the first orally available highly selective HDAC6 inhibitor, and its efficacy and therapeutic effects are being continuously verified. This review summarizes the research progress of ACY-1215 in cancer and other human diseases, as well as the underlying mechanism, in order to guide the future clinical trials of ACY-1215 and more in-depth mechanism researches

Endoscopic full-thickness resection for a gastric angioleiomyoma.

Angioleiomyoma (ALM) is a rare benign tumor, which is generally occurs on extremity, particularly the lower legs. It is composed of varied smooth muscle bundles and vascular channels. In this letter to editor, we describe the first case report of gastric ALM

Shear-Wave Splitting Analysis Using Optimization Algorithms

AbstractShear-wave splitting (SWS) analysis is used to predict fractures in subsurface media. Specifically, two parameters relevant to SWS analysis (the azimuth of the fast shear wave and the time delay between the fast and slow shear waves) are used to quantify the main azimuth and degree of the fracture development, respectively. However, the algorithms of SWS analysis using a grid search have relatively low computational efficiency, as they need to calculate the objective function values of all grid points. To improve the efficiency of SWS analysis, we proposed new algorithms using the gradient descent, Newton, and advance-retreat methods. The new methods use the direction of the fastest gradient descent, the intersection points of the tangent plane of the first-order objective function with the zero plane, and narrowing the range of extremum points to determine the search path. Therefore, this removes the necessity to compare all grid points in the value region. We compared the three methods and the rotation-correlation method, and both synthetic and field data tests indicated that all three methods had higher computational efficiency than the traditional grid search method. Among the proposed methods, the gradient-descent method obtained the most accurate results for both synthetic and field data. Our study shows that SWS analysis combined with the gradient-descent method can accurately and efficiently obtain SWS parameters for fracture prediction

A Case of Penile Squamous Cell Carcinoma Associated with HPV58 Infection

We report the case of a 55-year-old man with penile squamous cell car- cinoma (SCC). We found a mass in the patient’s penis, which gradually increased in size. We performed a partial penectomy to remove the mass. Histopathology revealed a highly differentiated squamous cell carcinoma. Human papillomavirus (HPV) DNA was detected by polymerase chain reaction. HPV was found to be pres- ent in the squamous cell carcinoma, and sequencing analysis showed that it was type 58

Characteristic analysis of adverse reactions of five anti-TNFɑ agents: a descriptive analysis from WHO-VigiAccess

Introduction: Tumor necrosis factor (TNF) inhibitors (adalimumab, infliximab, etanercept, golimumab, and certolizumab pegol) have revolutionized the treatment of severe immune-mediated inflammatory diseases, including rheumatoid arthritis, Crohn’s disease, psoriatic arthritis, ankylosing spondylitis, and ulcerative colitis. This study assessed adverse drug reactions (ADRs) after the use of TNFα inhibitors in VigiAccess of the World Health Organization (WHO) and compared the adverse reaction characteristics of five inhibitors to select the drug with the least risk for individualized patient use.Methods: The study was a retrospective descriptive analysis method in design. We sorted out five marketed anti-TNFα drugs, and their ADR reports were obtained from WHO-VigiAccess. Data collection included data on the age groups, sex, and regions of patients worldwide covered by ADR reports, as well as data on disease systems and symptoms caused by ADRs recorded in annual ADR reports and reports received by the WHO. By calculating the proportion of adverse reactions reported for each drug, we compared the similarities and differences in adverse reactions for the five drugs.Results: Overall, 1,403,273 adverse events (AEs) related to the five anti-TNFα agents had been reported in VigiAccess at the time of the search. The results show that the 10 most commonly reported AE manifestations were rash, arthralgia, rheumatoid arthritis, headache, pneumonia, psoriasis, nausea, diarrhea, pruritus, and dyspnea. The top five commonly reported AE types of anti-TNFα drugs were as follows: infections and infestations (184,909, 23.0%), musculoskeletal and connective tissue disorders (704,657, 28.6%), gastrointestinal disorders (122,373, 15.3%), skin and subcutaneous tissue disorders (108,259, 13.5%), and nervous system disorders (88,498, 11.0%). The preferred terms of myelosuppression and acromegaly were obvious in golimumab. Infliximab showed a significantly higher ADR report ratio in the infusion-related reaction compared to the other four inhibitors. The rate of ADR reports for lower respiratory tract infection and other infections was the highest for golimumab.Conclusion: No causal associations could be established between the TNFα inhibitors and the ADRs. Current comparative observational studies of these inhibitors revealed common and specific adverse reactions in the ADR reports of the WHO received for these drugs. Clinicians should improve the rational use of these high-priced drugs according to the characteristics of ADRs