Anisotropy Dependence of Material Deformation Mechanisms in Nanoscratching Monocrystalline BaF: Experiments and Atomic Simulations.

Monocrystalline barium fluoride (BaF), known for its exceptional optical properties in the infrared spectrum, exhibits anisotropy that influences surface quality and material removal efficiency during ultraprecision machining. This research explores the impact of anisotropy on the deformation and removal mechanisms of monocrystalline BaF by integrating nanoscratch tests with molecular dynamics (MD) simulations. Nanoscratch tests conducted on variously oriented monocrystalline BaF surfaces using a ramp loading mode facilitated the identification of surface cracks and a systematic description of material removal behaviors.

Autoencoder assisted subcarrier optimization for nonlinear frequency division multiplexing.

Nonlinear frequency division multiplexing (NFDM) is a novel optical communication technique that can achieve nonlinear free transmission. However, current design of NFDM is analogous to orthogonal frequency division multiplexing (OFDM), where sinc function is utilized as subcarriers, which may not be optimal for nonlinear spectrums. In this paper, we propose an auto-encoder (AE) assisted subcarrier optimization scheme for dual-polarized (DP) NFDM systems.

Anisotropic Deformation Behavior and Indentation Size Effect of Monocrystalline BaF Using Nanoindentation.

In this study, our objective is to investigate the anisotropic deformation behavior and the indentation size effect (ISE) of monocrystalline barium fluoride (BaF) using nanoindentation experiments with a diamond Berkovich indenter. BaF is known for its anisotropy, which results in significant variations in its mechanical properties. This anisotropy poses challenges in achieving high processing quality in ultra-precision machining.

Improvement for a full-spectrum modulated nonlinear frequency division multiplexing transmission system.

Nonlinear frequency division multiplexing (NFDM), as a possible technique to overcome the limit imposed by Kerr nonlinearity in conventional coherent optical communication systems, has attracted widespread attention in the communication community in recent years. In order to fully utilize the available degrees of freedom in the nonlinear spectrum, this paper focuses on the full-spectrum (FS) modulated NFDM system. First, we maximize the data rate of discrete spectrum (DS) by optimizing the distribution of eigenvalues in DS part of FS.

Optimisation of Lapping Process Parameters for Single-Crystal 4H-SiC Using Orthogonal Experiments and Grey Relational Analysis.

Lapping is one of the standard essential methods to realise the global planarization of SiC and other semiconductor substrates. It is necessary to deeply study the mechanism to obtain SiC lapping process parameters with a strong comprehensive lapping performance (i.e.

Probabilistic shaping and neural network-based optimization for a nonlinear frequency division multiplexing system.

A joint scheme introducing probabilistic shaping (PS) at the transmitter and utilizing a neural network (NN) equalizer at the receiver is proposed to improve the performance of the -modulated nonlinear frequency division multiplexing (NFDM) system. Through a numerical simulation, we demonstrate that PS plays a leading role for low launch power case, which improves the performance of the system effectively, while the NN equalizer's superiority appears in a high launch power region, whose main role is to weaken the correlation among subcarriers for improving system performance. The proposed scheme would enlighten the optimum modulation and detection schemes of the NFDM system.

Scratch Behaviour of Bulk Silicon Nitride Ceramics.

SiN ceramic is generally recognized as being difficult to machine due to its hardness and brittleness. It is necessary to control the normal load applied and the machined depth of the abrasive particles in order to eliminate surface/subsurface damage and defects during the grinding or polishing. In this study, scratch experiments were conducted on the polished surface of SiN specimens to investigate the brittle-ductile transformation and the evolution of material removal mechanisms.

Effective prevention and management of COVID-19 in outpatient hemodialysis patients.

The authors introduce a mobile phone app that may effectively prevent and manage coronavirus disease 2019 (COVID-19) in outpatient hemodialysis patients in Sichuan Province, China.

Prevalence of Kaschin-Beck disease among Tibetan children in Aba Tibetan and Qiang Autonomous Prefecture: a 3-year epidemiological survey.

Background: Kaschin-Beck disease (KBD), a special type of osteoarthritis, is a disabling degenerative disease and it can cause severe dysarthrosis of joints. This study was undertaken to investigate the prevalence of KBD among Tibetan children in the Aba Tibetan and Qiang Autonomous Prefecture in Sichuan Province and to provide evidence for KBD control in the western regions of China.

Methods: Eleven counties were selected as the monitoring regions and all Tibetan children aged 6-13 years were selected as the study subjects.

Genetic variants in the HLA-DRB1 gene are associated with Kashin-Beck disease in the Tibetan population.

Objective: To investigate the association between variants in the HLA-DRB1 gene and Kashin-Beck disease (KBD), as well as associations of selenium and iodine deficiencies with KBD in a Tibetan population.

Methods: Fourteen single-nucleotide polymorphisms (SNPs) were genotyped around the HLA-DRB1 gene, and HLA-DRB1 allele genotyping was performed in a discovery cohort, composed of 605 patients with KBD and 393 control subjects, and/or a replication cohort, composed of 290 patients with KBD and 295 controls. Plasma concentrations of selenium and iodine were measured and compared by t-test in 299 patients with KBD and 280 controls from the same villages.

The effect of Kashin-Beck disease-affected feed and T-2 toxin on the bone development of Wistar rats.

Objective: To investigate the effect of Kashin-Beck disease (KBD)-affected feed and T-2 toxin on the bone development of Wistar rats.

Methods: Seventy-eight ablactation Wistal rats (50% male and 50% female) weighing approximately 65 g were obtained from Sichuan Medical Center (Chengdu, China), and were randomly assigned to three groups (Groups A, B and C). Group A had 24 rats and were fed with commercial rat feed (control); Group B had 30 rats and were fed with commercial rat feed and T2 toxin by intragastric administration; and Group C had 24 rats and were fed with the KBD-affected feed.

[Surveillance on Keshan disease from 1990 to 2008 in Sichuan province].

Objective: To study the epidemiological characteristics of Keshan disease (KD) and its trend so as to provide evidences for further research, prevention and treatment of the disease in Sichuan province.

Methods: Based on KD related data from 1990 to 2008, descriptive method was used to analyze the epidemiological characteristics of KD.

Results: 87 KD cases were identified during the 19 years.