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A novel superhard structure of TiB3 is predicted and its phase transitions, mechanical properties and electronic structure up to 200 GPa are studied employing first-principles calculation. We propose a new structure by substituting the highly stable Amm2 structure with excellent mechanical properties in VB3. Enthalpy calculations demonstrate its superior energetic stability compared to the previously predicted C2/m structure via particle swarm optimization. Furthermore, it maintains stability up to 93.8 GPa and transforms into a P2/m structure under further compression. The Amm2 structure stands as a novel superhard phase with a hardness of 51.6 GPa by Chen’s model, surpassing the C2/m structure by 3.2 GPa. This disparity arises from structural distinctions, with the Amm2 structure featuring boron plates consisting of more layers, resulting in stronger B-B interactions. This novel superhard structure stands as the hardest reported Ti-B compound to date, poised to replace conventional superhard material c-BN in cutting tools and wear-resistant coatings.

Abstract Anterior cruciate ligament (ACL) injury, a common sports injury, is associated with a high risk of subsequent osteoarthritis (OA), which can cause serious pain and disability. Understanding the detailed mechanism underlying the predisposition of knee with ACL injury to secondary OA at an early stage is key to preventing future degradation and progression to a clinically significant disease. A total of 56 male Sprague Dawley rats (age, 8 weeks; weight, 180–220 g) were randomly divided into three experimental groups: control, ACL transection (ACLT; where surgical procedure was performed with ACLT), and sham (where surgical procedure was performed without ACLT). The ACLT and sham groups were further divided into three subgroups based on when the rats were sacrificed: 4, 8, and 12 weeks after the surgical procedure. The control group and the aforementioned subgroups contained 8 rats each. We used nuclear magnetic resonance (NMR)-based metabolomic analysis to analyze rat serum samples for the metabolic characteristics and the underlying mechanisms. In total, 28 metabolites were identified in the NMR spectra of the rat sera. At 4 and 8 weeks postoperatively, the sham group demonstrated metabolic profiles different from those of the ACLT group. However, this difference was not observed 12 weeks postoperatively. In total, five metabolites (acetate, succinate, sn-glycero-3-phosphocholine, glucose, and phenylalanine) and five metabolic pathways (phenylalanine, tyrosine, and tryptophan biosynthesis; phenylalanine metabolism; pyruvate metabolism; starch and sucrose metabolism; and histidine metabolism) demonstrated significant differences between the ACLT and sham groups. ACL injury was noted to considerably affect biochemical homeostasis and metabolism; however, these metabolic changes persisted briefly. Moreover, glucose was a characteristic metabolite, and several energy-related metabolic pathways were significantly disturbed. Therefore, an ACL injury may lead to considerable impairments in energy metabolism. Abnormal glucose levels facilitate chondrocyte function impairment and thereby lead to OA progression. Furthermore, lactate may aid in identifying metabolic changes specific to knee trauma not related to an ACL injury. Overall, the metabolic changes in rat serum after an ACL injury were closely related to disturbances in energy metabolism and amino acid metabolism. The current results may aid in understanding the pathogenesis of posttraumatic osteoarthritis.

In recent years, with the continuous improvement of computer science and technology, artificial intelligence(AI)technology based on deep learning(DL)has developed rapidly and attracted wide attention all over the world. Great progress has been made in the research and application of AI in the medical field. In the field of optometry, AI can assist the diagnosis of myopia, strabismus, amblyopia and other diseases, and has achieved good results in the screening and early diagnosis of keratoconus as well as in the prevention and correction of myopia. Nevertheless, there are some limitations and great challenges in the application of AI in optometry, including clinical and technical challenges, interpretability of algorithmic results, medical legal issues and so on. This paper reviews the application, limitation and prospect of AI in the field of optometry.

Myopia is a common ocular disorder. In recent years, the incidence of myopia presents an increasing trend year by year. Patients with high myopia are at an increased risk for severe visual impairment. The economic and societal impacts of complication associated with myopia are enormous. Therefore, it is essential and imminent for implementing effective myopia control strategies. The results of the current study suggest that uncontrolled axial elongation produced by periphral hyperopic defocus could be one of the possible mechanisms for myopia development, multiple strategies especially optical defocus technology based on this are increasingly becoming part of the mainstream clinical practice in myopia management. This article reviews the principle of optical defocus on myopia control, experimental research on defocus myopia animals, and the latest clinical applications of different optical defocus technologies on myopia control, summarizes the clinical research results of myopia control using progressive addition spectacle lenses, peripheral defocus spectacle lenses, defocus incorporated multiple segments spectacle lenses, orthokeratology contact lenses and multifocal soft contact lenses. It is proposed to provide a new option for the treatment plan to delay the progression of myopia.

AIM:To investigate the application of multi-mode teaching steered by “HOPE” in the clinical teaching of contact lens.METHODS: Prospective study. Two classes(totally 80 students)of 2018 grade major in optometry, Nanjing Medical University, were randomly selected as experimental group(40 students, 18 males, 22 females)using multi-mode teaching(including problem-based learning, case-based learning and flipped classroom),and control group(40 students, 19 males, 21 females)using traditional teaching mode. At the end of the course, the teaching effects were evaluated by usual performance, network examination, theory test, operation test and questionnaire.RESULTS: The assessment result at ordinary times: the points of experiment group(16.46±2.19)points was higher than the control group(13.81±2.95)points(t=6.36, P

Abstract Objective To investigate the response of the infrapatellar fat pad (IFP) to running at different intensities and further explore the underlying mechanisms of these responses under different running-induced loadings. Methods Animals were randomly assigned into the sedentary (SED), low-intensity running (LIR), medium-intensity running (MIR), and high-intensity running (HIR) groups. The rats in the LIR, MIR, and HIR groups were subjected to an 8-week treadmill running protocol. In each group, the IFP was examined at the baseline and at the 8th week to perform histomorphology, immunohistochemistry, and mRNA expression analyses. Results Compared with LIR and MIR, HIR for 8 weeks led to a substantial increase in the surface cellularity (1.67 ± 1.15), fibrosis (1.29 ± 0.36), and vascularity (33.31 ± 8.43) of the IFP but did not increase IFP inflammation or M1 macrophage polarization. Low-to-medium-intensity running resulted in unchanged or decreased fibrosis, vascularity, and surface cellularity in the IFP compared to those of the SED group. Furthermore, serum leptin and visfatin levels were significantly lower in the LIR and MIR groups than in the SED group or the HIR group (P < 0.05). Conclusion The effect of running on IFP remodeling was intensity dependent. In contrast to LIR and MIR, HIR increased the fibrosis and vascularity of the IFP. HIR-induced IFP fibrosis was probably due to mechanical stress, rather than pathological proinflammatory M1/M2 polarization.

Abstract Objective To perform a meta-analysis comparing the structural progression and clinical symptom outcomes as well as adverse events experienced from intra-articular injections of sprifermin compared to a placebo treatment for patients with knee osteoarthritis (KOA). Method We systematically searched the literature for studies that compared long-term outcomes between sprifermin and placebo injections for KOA treatment. Meta-analysis was performed with RevMan5.3 using an inverse variance approach with fixed or random effects models. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated. Results Eight studies were included. Overall, there was significantly less improvement of WOMAC total scores in patients receiving sprifermin, compared with the placebo (mean difference (MD) = 3.23, 95% CI 0.76–5.69; I 2 = 0%; P = 0.01). Further, sprifermin injection patients gained more, and lost less, cartilage thickness and volume in total femorotibial joint (cartilage thickness: standardized mean differences (SMD) = 0.55, 95% CI 0.26–0.84; I 2 = 78%; P = 0.0002; cartilage volume: SMD = 0.39, 95% CI 0.20–0.58; I 2 = 49%; P

AIM: To compare the consistency of IOL Master 700 with IOL Master 500 and A-mode ultrasound for biological measurements, and evaluate the measurements of IOL Master 700 in preoperative examinations of cataract patients. METHODS:In this prospective study, a total of 52 patients(100 eyes)diagnosed as age-related cataract were selected at the Nanjing Medical University Eye Hospital. All the patients were examined in turn by IOL Master 700, IOL Master 500 and A-mode ultrasound. Measurements by these three instruments were compared for axial length(AL), corneal curvature(Km), central anterior chamber depth(ACD), white-to-white(W-W)and pupil diameter(P). The results were analyzed by one-way ANOVA, Pearson correlation and Bland-Altman. RESULTS: The detection rates of AL and ACD with IOL Master 700, IOL Master 500 and A-mode ultrasound were 98%, 87%, 99% and 100%, 99%, 99%; respectively. The detection of Km with IOL Master 700 and IOL Master 500 were 100%, 99%. The detection of W-W and P were both 99%. Among them, 24 eyes had high myopia, posterior scleral grape swelling and axial length ≥26mm. The detection of AL with IOL Master 700, IOL Master 500 and A-mode ultrasound were 96%, 79%, 96%. There was a significant difference in AL and ACD between three instruments(F=11.58, P=0.03; F=12.46, P=0.02). There were no significant differences in Km, W-W and P parameters among three instruments(all P>0.05). The average difference between three instruments for AL measurement: IOL Master 700 and IOL Master 500 was 0.05±0.12mm, IOL Master 700 and A-mode ultrasound was 0.16±0.14mm; The average difference between three instruments for AL measurement in axial length≥26mm: IOL Master 700 and IOL Master 500 was 0.17±0.16mm, IOL Master 700 and A-mode ultrasound was 0.55±0.22mm. The Pearson's correlation analysis showed that there was a high correlation between the measured results of each equipment. The consistency of AL results using Bland-Altman analysis showed there was good consistency in the range of 95% consistency.CONCLUSION: There was high consistency in ocular biological measurements between three instruments in cataract eyes. However, the detection rate of IOL Master 700 in AL was higher than that of IOL Master 500, and the accuracy of the IOL Master 700 measurement was higher in the AL measurement in high myopia with posterior staphyloma. Compared with traditional examination equipment, IOL Master 700 has better penetration and accuracy to provide more accurate measurement parameters.

AIM: To observe the short-term efficacy of intravitreal injection of aflibercept on macular edema secondary to retinal vein occlusion(RVO). METHODS: Totally 24 patients(24 eyes)with macular edema secondary to RVO confirmed by ophthalmic clinical examination received intravitreal injection of aflibercept from May to October in 2019 in hospital. Before and after the 1wk, 1mo treatment, all the eyes of the sick were examined with best corrected visual acuity(BCVA), optical coherence tomography angiography(3x3mm scanning range model)BCVA, central macular thickness(CMT), vascular density of superficial capillary plexus(SCP), vascular density of deep capillary plexus(DCP), and the area, perimeter and the roundness index in foveal avascular zone(FAZ)were observed. RESULTS: Intravitreal injection of aflibercept for 1wk and 1mo, BCVA improved with the difference were statistically significant(PPP>0.05), and it revealed there was no obvious change for vascular density of SCP,DCP and FD-300(All P>0.05); The area and perimeter of FAZ after treatment increased obviously, and the roundness index of FAZ decreased than before with the difference were statistically significant(PCONCLUSION: For macular edema secondary to RVO, eyesight improved and edema absorbed obviously with the intravitreal injection of aflibercept in short-term clinical observation. At the same time, FAZ become regular and macular ischemia wasn't aggravated after treatment.

Abstract Post-traumatic osteoarthritis (PTOA) develops after joint injury. Specifically, patients with anterior cruciate ligament (ACL) injury have a high risk of developing PTOA. In this review, we outline the incidence of ACL injury that progresses to PTOA, analyze the role of ACL reconstruction in preventing PTOA, suggest possible mechanisms thought to be responsible for PTOA, evaluate current diagnostic methods for detecting early OA, and discuss potential interventions to combat PTOA. We also identify important directions for future research. Although much work has been done, the incidence of PTOA among patients with a history of ACL injury remains high due to the complexity of ACL injury progression to PTOA, the lack of sensitive and easily accessible diagnostic methods to detect OA development, and the limitations of current treatments. A number of factors are thought to be involved in the underlying mechanism, including structural factors, biological factors, mechanical factors, and neuromuscular factor. Since there is a clear “start point” for PTOA, early detection and intervention is of great importance. Currently, imaging modalities and specific biomarkers allow early detection of PTOA. However, none of them is both sensitive and easily accessible. After ACL injury, many patients undergo surgical reconstruction of ACL to restore joint stability and prevent excessive loading. However, convincing evidence is still lacking for the superiority of ACL-R to conservative management in term of the incidence of PTOA. As for non-surgical treatment such as anti-cytokine and chemokine interventions, most of them are investigated in animal studies and have not been applied to humans. A complete understanding of mechanisms to stratify the patients into different subgroups on the basis of risk factors is critical. And the improvement of standardized and quantitative assessment techniques is necessary to guide intervention. Moreover, treatments targeted toward different pathogenic pathways may be crucial to the management of PTOA in the future.

AIM: To observe vascular density and foveal avascular zone(FAZ)in macular area for diabetic macular edema(DME)with optical coherence tomography angiography(OCTA)when before and after intravitreal injection of rainbizumab.METHODS: For the 45 DME patients(52 eyes)whose diagnosis were confirmed by ophthalmic clinical examination, their sick eyes were examined by OCTA with macular area 3x3mm scanning range model when before and 1wk after intravitreal injection of rainbizumab, and obtain vascular density of superficial capillary plexus(SCP), deep capillary plexus(DCP), and the number of microaneurysm and the area, perimeter and the roundness index in FAZ, and do block matching t-test.RESULTS: There was no statistical difference for the vascular density of SCP before and after treatment(t=1.635, P=0.10). Vascular density(46.59%±4.91%)of DCP after treatment were more than before treatment(42.47%±4.16%), and it was statistically significant difference(t=1.014, P=0.02). There was no statistical difference for the number of microaneurysm in SCP when before and after treatment(t=1.623, P=0.21); But the number of microaneurysm(6.10±0.67)in DCP after treatment decreased obviously than before treatment(8.21±0.41),and the difference was statistically significant(t=1.124, P=0.01). The area and perimeter of FAZ after treatment increased than before treatment, but there was no statistical difference(P>0.05); The roundness index of FAZ after treatment was lower than before treatment,and there was also no statistical difference(P>0.05).CONCLUSION: The capillary circulation in DCP increased in short term for sick eyes of DME after intravitreal injection of rainbizumab, and the number of microaneurysm in DCP reduced, but the change in SCP is not obvious. At the same time, the area, perimeter and the roundness index of FAZ had no significant meaning of clinical observation for DME with injection of rainbizumab.

Abstract Here, we report a 41‐year‐old female with type II VUF after hysteromyomectomy.We report the diagnosis of VUF by imaging method, and provide a feasible treatment for this complication after pelvic surgery.

Various strategies have been designed to contain the COVID-19 pandemic. Among them, vaccine development is high on the agenda in spite of the unknown duration of the protection time. Various vaccines have been under clinical trials with promising results in different countries. The protective efficacy and the short-term and long-term side effects of the vaccines are of major concern. Therefore, comparing the protective efficacy and risks of vaccination is essential for the global control of COVID-19 through herd immunity. This study reviews the most recent data of 12 vaccines to evaluate their efficacy, safety profile and usage in various populations.

The carbon market is regarded as one of the important means to achieve China's dual carbon target. It has ancillary effect for reducing air pollution while regulating carbon emissions since climate change and air pollution share the same origin and homology. Research on how to design the carbon market mechanism in order to maximize the synergistic effect of reducing greenhouse gas and air pollution will have a very important practical impact for China. This study conducts a theoretical analysis of the collaborative emission reduction path of China's carbon market, and constructs an Energy-Economy-Environment (3E) model of the collaborative emission reduction effect of carbon trading system based on System Dynamics. After analyzing the feedback path of the core cycle of the model and verifying its performance, three main policy factors in the carbon market are explored, and their effects under the dual objectives of emission control and economic development are comprehensively evaluated. This study suggests that the exploration of the potential of carbon market for collaborative governance should be accelerated, and ensure the orderly expansion of coverage and precise setting of limits, so as to ensure the smooth achievement of carbon reduction targets while guaranteeing the social and economic development.

Osteoarthritis is the most prevalent arthritis typically characterized by degradation of cartilage. However, its pathogenesis is not fully understood. Currently, osteoarthritis is best considered a disease of the whole "joint organ". Infrapatellar fat pad (IFP), an adipose tissue near synovium, is now attaching importance to researchers for its inflammatory phenotype. In this narrative review, a large body of evidence has been gathered for the involvement of IFP in the development of knee osteoarthritis. Additionally, the underlying mechanisms of how IFP can be involved in this process have been proposed. However, further investigations are needed to better understand its precise role in this process and its underlying mechanism, and beyond that, to develop new strategies to slow down the degenerative process and explore an effective and timely diagnosis of the disease. [ABSTRACT FROM AUTHOR]

Tracking maneuvering target in real time autonomously and accurately in an uncertain environment is one of the challenging missions for unmanned aerial vehicles (UAVs). In this paper, aiming to address the control problem of maneuvering target tracking and obstacle avoidance, an online path planning approach for UAV is developed based on deep reinforcement learning. Through end-to-end learning powered by neural networks, the proposed approach can achieve the perception of the environment and continuous motion output control. This proposed approach includes: (1) A deep deterministic policy gradient (DDPG)-based control framework to provide learning and autonomous decision-making capability for UAVs; (2) An improved method named MN-DDPG for introducing a type of mixed noises to assist UAV with exploring stochastic strategies for online optimal planning; and (3) An algorithm of task-decomposition and pre-training for efficient transfer learning to improve the generalization capability of UAV’s control model built based on MN-DDPG. The experimental simulation results have verified that the proposed approach can achieve good self-adaptive adjustment of UAV’s flight attitude in the tasks of maneuvering target tracking with a significant improvement in generalization capability and training efficiency of UAV tracking controller in uncertain environments.

Blockchain is becoming more and more popular in various fields. Since the information transmission mode of the blockchain is data broadcasting, the traditional TCP/IP network cannot support the blockchain system well, but the Named-Data Networking (NDN) could be a good choice because of its multi-path forwarding and intra-network caching functions. In this article, we propose a new blockchain information transmission acceleration strategy (AITS) combining with graph theory and probability theory based on the NDN architecture. We select some more important nodes in the network as “secondary nodes”, and give them more bandwidth and cache space to assist the NDN network in data transmission. In order to select the correct node as the secondary node, we present a method to calculate the number of secondary nodes, and give the function to calculate the importance of each node. The simulation results show that in complex networks, the proposed method has superior performance in accelerating information transmission and reducing data overhead.

This study was carried out to evaluate the effects of graded levels of fiber from rice hull and the caecectomy on metabolizable energy (ME) and amino acid digestibility (AAD) in 42 Wuzong geese (21 intact and 21 caecectomized). The experiment was a 3×2 factorial randomized design with 3 fiber levels and 2 treatments of geese (caecectomized and intact). Each of the 3 diets was tube-fed (60 g) to 7 caecectomized and 7 intact adult Wuzong geese that had been fasted for 24 h. Excreta were collected for the next 48 h. The same geese were also fasted for estimation of endogenous losses of amino acids (AA) and energy after short period recovery. AA content and metabolizable energy value were determined in the excreta. In general, significant effects were found for fiber levels on apparent digestibility of Thr, Leu, Pro, Glu, Val, Ala and total AA (P0.05), except for Lys and Try (P

Ecohydrology and hydropedology are two emerging fields that are interconnected. In this study, we demonstrate stemflow hydrology and preferential water flow along roots in two desert shrubs (H. scoparium and S. psammophila) in the south fringe of Mu Us sandy land in North China. Stemflow generation and subsequent movement within soil-root system were investigated during the growing seasons from 2006 to 2008. The results indicated that the amount of stemflow in H. scoparium averaged 3.4% of incident gross rainfall with a range of 2.3–7.0%, while in S. psammophila stemflow averaged 6.3% with a range of 0.2–14.2%. Stemflow was produced from rainfall events with total amount more than 1 mm for both shrubs. The average funneling ratio (the ratio of rainfall amount delivered to the base of the tree to the rainfall that would have reached the ground should the tree were not present) was 77.8 and 48.7 for H. scoparium and S. psammophila, respectively, indicating that branches and stems were fully contributing to stemflow generation and thereby provided sources of water for possible preferential flow into deeper soil layer. Analysis of Rhodamine-B dye distribution under the shrubs showed that root channels were preferential pathways for the movement of most stemflow water into the soil. Distribution of soil water content under the shrubs with and without stemflow ascertained that stemflow was conducive to concentrate and store water in deeper layers in the soil profiles, which may create favorable soil water conditions for plant growth under arid conditions. Accordingly, a clear linkage between aboveground ecohydrology and belowground hydropedology in the desert shrubs is worth noticing, whereby an increase in stemflow would result in an increase in soil hydrologic heterogeneity.