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The intrinsic variability of memristor switching behavior can be used as a natural source of randomness, this variability is valuable for safe applications in hardware, such as the true random number generator (TRNG). However, the speed of TRNG is still be further improved. Here, we propose a reliable Ag/SiNx/n-Si volatile memristor, which exhibits a typical threshold switching device with stable repeat ability and fast switching speed. This volatile-memristor-based TRNG is combined with nonlinear feedback shift register (NFSR) to form a new type of high-speed dual output TRNG. Interestingly, the bit generation rate reaches a high speed of 112 kb/s. In addition, this new TRNG passed all 15 National Institute of Standards and Technology (NIST) randomness tests without post-processing steps, proving its performance as a hardware security application. This work shows that the SiNx-based volatile memristor can realize TRNG and has great potential in hardware network security. [ABSTRACT FROM AUTHOR]

Neuromorphic computing aims to achieve artificial intelligence by mimicking the mechanisms of biological neurons and synapses that make up the human brain. However, the possibility of using one reconfigurable memristor as both artificial neuron and synapse still requires intensive research in detail. In this work, Ag/SrTiO3(STO)/Pt memristor with low operating voltage is manufactured and reconfigurable as both neuron and synapse for neuromorphic computing chip. By modulating the compliance current, two types of resistance switching, volatile and nonvolatile, can be obtained in amorphous STO thin film. This is attributed to the manipulation of the Ag conductive filament. Furthermore, through regulating electrical pulses and designing bionic circuits, the neuronal functions of leaky integrate and fire, as well as synaptic biomimicry with spike-timing-dependent plasticity and paired-pulse facilitation neural regulation, are successfully realized. This study shows that the reconfigurable devices based on STO thin film are promising for the application of neuromorphic computing systems. [ABSTRACT FROM AUTHOR]

Ferroptosis is an iron‐dependent cell death that has been found to aggravate the progression of osteoarthritis (OA) and gut microbiota‐ OA axis refers to the bidirectional information network between the gut microbiota and OA, which may provide a new way to protect the OA. However, the role of gut microbiota‐derived metabolites in ferroptosis‐relative osteoarthritis remains unclear. The objective of this study was to analyze the protective effect of gut microbiota and its metabolite capsiate (CAT) on ferroptosis‐relative osteoarthritis in vivo and in vitro experiments. From June 2021 to February 2022, 78 patients were evaluated retrospectively and divided into two groups: The health group (n = 39) and the OA group (n = 40). Iron and oxidative stress indicators were determined in peripheral blood samples. And then in vivo and in vitro experiments, a surgically destabilized medial meniscus (DMM) mice model was established and treated with CAT or Ferric Inhibitor‐1 (Fer‐1). Solute Carrier Family 2 Member 1 (SLC2A1) short hairpin RNA (shRNA) was utilized to inhibit SLC2A1 expression. Serum iron was increased significantly but total iron binding capacity was decreased significantly in OA patients than healthy people (p < 0.0001). The least absolute shrinkage and selection operator clinical prediction model suggested that serum iron, total iron binding capacity, transferrin, and superoxide dismutase were all independent predictors of OA (p < 0.001). Bioinformatics results suggested that SLC2A1, Metastasis‐Associated Lung Adenocarcinoma Transcript 1 (MALAT1), and HIF‐1α (Hypoxia Inducible Factor 1 Alpha)‐related oxidative stress signaling pathways play an important role in iron homeostasis and OA. In addition, gut microbiota 16s RNA sequencing and untargeted metabolomics were used to find that gut microbiota metabolites CAT in mice with osteoarthritis were negatively correlated with Osteoarthritis Research Society International (OARSI) scores for chondrogenic degeneration (p = 0.0017). Moreover, CAT reduced ferroptosis‐dependent osteoarthritis in vivo and in vitro. However, the protective effect of CAT against ferroptosis‐dependent osteoarthritis could be eliminated by silencing SLC2A1. SLC2A1 was upregulated but reduced the SLC2A1 and HIF‐1α levels in the DMM group. HIF‐1α, MALAT1, and apoptosis levels were increased after SLC2A1 knockout in chondrocyte cells (p = 0.0017). Finally, downregulation of SLC2A1 expression by Adeno‐associated Virus (AAV) ‐SLC2A1 shRNA improves osteoarthritis in vivo. Our findings indicated that CAT inhibited HIF‐1a expression and reduced ferroptosis‐relative osteoarthritis progression by activating SLC2A1. [ABSTRACT FROM AUTHOR]

This paper studies the automatic carrier landing controller design problem with output constraint and fixed-time convergence requirements. The proposed flight controller is separated into guidance, attitude control, and approach power compensation system. In each submodule, universal barrier Lyapunov function and fixed-time control scheme are applied in the controller design. In addition, adaptive estimation method is incorporated to improve the robustness to the external disturbances. The proposed controller ensures the position tracking error, attitude tracking error, and angle of attack tracking error not violate the predesigned boundaries, while the tracking errors will converge to a small set around zero in fixed-time. The output constraint and fixed-time convergence properties of the proposed controller improve the landing security to a narrow flight deck in a limited operation time. The simulation results verify the proposed controller in automatic carrier landing mission. [ABSTRACT FROM AUTHOR]

Backgrounds: Diabetic retinopathy (DR) is one of the most severe microvascular complications of diabetes mellitus (DM). Secreted protein acidic and rich in cysteine (SPARC) has been found to play an important role in many diseases, but its role and mechanism in DR remain unknown. Methods: We studied the role of SPARC and integrin β1 in vascular pathophysiology and identified potential therapeutic translation. The SPARC levels were tested in human serum and vitreous by ELISA assay, and then the Gene Expression Omnibus (GEO) dataset was used to understand the key role of the target gene in DR. In human retinal capillary endothelial cells (HRCECs), we analyzed the mRNA and protein level by RT-PCR, immunohistochemistry, and Western blotting. The cell apoptosis, cell viability, and angiogenesis were analyzed by flow cytometry, CCK-8, and tube formation. Results: In this study, we investigated the role of SPARC in the development and progression of human DR and high glucose-induced HRCEC cells and found that the SPARC-ITGB1 signaling pathway mimics early molecular and advanced neurovascular pathophysiology complications of DR. The result revealed that DR patients have a high-level SPARC expression in serum and vitreous. Knockdown of SPARC could decrease the expressions of inflammatory factors and VEGFR, inhibit cell apoptosis and angiogenesis, and increase cell viability by regulating integrin β1 in HRCECs. Conclusion: SPARC promotes diabetic retinopathy via the regulation of integrin β1. The results of this study can provide a potential therapeutic application for the treatment of DR. [ABSTRACT FROM AUTHOR]

Background: Total knee arthroplasty (TKA) is an important treatment for knee osteoarthritis, but the result of whole-body vibration (WBV) in knee function rehabilitation and bone loss with osteopenia was unknown. Therefore, the purpose of this study is to study whether low-frequency, low-amplitude WBV can improve the clinical outcome of knee osteoarthritis. Methods: This study was randomized and included 67 osteopenic patients (55–90 years, 85% women) for TKA surgery (control group N = 32, WBV group N = 35). All selected patients after TKA surgery tested clinical results, such as knee function and bone mass in baseline, 3 months after surgery, and 6 months after surgery. Results: Compared to the control group, the WBV group improved pain scores, thigh circumference, lower limb muscle strength, joint activity, and joint function in 6 months after surgery. WBV intervention also improves bone density in the spine, the microstructure of the radius and tibia, and the bone turnover marker. At 3 months after TKA surgery, the WBV group had no significant effect on knee function and bone loss. Conclusions: Whole-body vibration for osteopenic patients with knee arthroplasty showed good therapeutic results in 6 months after TKA surgery, but the long-term therapeutic effect still needs to be further observed. [ABSTRACT FROM AUTHOR]

Osteoporosis and osteoarthritis are common diseases in an aging society, are considered metabolic diseases, and affect the quality of life of older adults. In addition, the gut microbiome is considered an additional organ to regulate bone metabolism. In the past decade, people have been studying the relationship between gut microbiota and bone metabolism. The role and mechanism of the gut microbiota in regulating bone metabolism is very important to improve the development of osteoporosis and osteoarthritis. Depletion of the gut microbiota as a method of studying the role of the gut microbiota was provided strategies to enhance the role of the gut microbiota in regulating osteoporosis and osteoarthritis. In this review, we discuss how depletion of the gut microbiota affects osteoporosis and osteoarthritis. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to observe the effects of long-term alendronate pretreatment on the healing of osteoporotic calvarial defects, and further investigate the effect of alendronate combined with once-weekly parathyroid hormone following 12 weeks of alendronate treatment in ovariectomized rats. Materials and methods: Thirty 3-month-old female rats were ovariectomized, and 24 rats received alendronate for 12 weeks. Then, a critical defect was created in the calvaria of all animals. Immediately after osteotomy, the animals received one of five treatments for 8 weeks: (1) continuation of vehicle (group E), (2) alendronate followed by vehicle (group A), (3) continuation of alendronate (group B), (4) alendronate followed by once-weekly parathyroid hormone alone (group C), or (5) continuation of alendronate combined with once-weekly parathyroid hormone (group D). Calvarial defect healing was assessed using dual-energy X-ray absorptiometry, micro-computed tomography, histology, and sequential fluorescence labeling. Results: Group E showed a significantly higher volume of newly formed bone than groups A, B, C, and D. Evidence of new dense bone formation in group E was observed histologically. In addition, the immunohistochemical expression of runt-related transcription factor 2 was increased in group E but inhibited in groups A, B, C, and D. Sequential immunofluorescence also showed inhibited mineral apposition in groups A, B, C, and D compared with group E. Conclusion: The present study shows that long-term pretreatment with alendronate inhibited calvarial defect healing in osteoporotic rats, and this effect could not be reversed by stopping alendronate, switching to parathyroid hormone, or combining with once-weekly parathyroid hormone. [ABSTRACT FROM AUTHOR]

Purpose: There are few reports about minimally invasive decompression and fixation for patients with thoracolumbar fracture and neurological symptoms. The previously reported method requires complete laminectomy, and removal of the medial part of the pedicle to expose the spinal canal for reduction. Thus, some approach-related damage to the bony structure and soft tissue still occurs. This study was performed to describe a modified minimally invasive tube technique for decompression and reduction of thoracolumbar fracture with neurological symptoms. This modified technique preserves most of the posterior structures of the spine as well as the muscle. Methods: Percutaneous pedicle screws were placed on the vertebrae superior and inferior to the fracture and at the fracture segment on the side with less severe symptoms. After retraction, the tube for decompression was placed on the facet joint where the decompression was needed. Under microscopic vision, part of the lamina and ligamentum flavum were removed to expose the spinal canal, and an L-shaped probe was used to reduce the bone fragment. Results: The modified method was successfully used in eight patients. Complete decompression was achieved and the bone fragment was safely reduced through the tube under microscopy in all cases. Fluoroscopy confirmed that the positioning of the percutaneous pedicle screw was good and the bone fragment was reduced. The neurological status was improved in all patients at last follow up. Conclusion: The modified method of minimally invasive decompression and fusion is effective in treating thoracolumbar fractures with neurological symptoms and preserves most of the ligaments and bone structure. [ABSTRACT FROM AUTHOR]

This study examined the effect of once‐weekly parathyroid hormone (PTH) combined with alendronate upon osteoporotic fracture healing after long‐term alendronate anti‐osteoporosis therapy. Seventy‐six 12‐week‐old female Sprague–Dawley rats were either sham operated or bilaterally ovariectomized (OVX). Following confirmation of osteoporosis 3 months after OVX, the remaining 64 animals received alendronate therapy. After 3 months of alendronate treatment, all rats underwent unilateral transverse tibial osteotomy. Animals were immediately randomly assigned to one of four groups: (1) alendronate followed by vehicle (ALN‐VEH), (2) continuation of alendronate (ALN‐ALN), (3) alendronate followed by once‐weekly PTH alone (ALN‐PTH), (4) continuation of alendronate combined with once‐weekly PTH (ALN‐ALN + PTH) until collection at 4 or 8 weeks after osteotomy. The fractured tibia was assessed using x‐ray, dual‐energy x‐ray absorptiometry, microcomputed tomography, biomechanical testing, histology, and sequential fluorescence labeling. The ALN‐ALN + PTH treatment significantly increased total callus volume, mineralized callus volume, mineralized callus volume/total callus volume, and biomechanical strength of the callus relative to ALN‐VEH and ALN‐PTH treatments at both 4 and 8 weeks and produced more mature trabecular bone compared with ALN‐ALN treatment at 8 weeks. RANKL/osteoprotegerin (OPG) are osteoclastogenesis markers, while cluster of differentiation 31 (CD31) is an important marker of angiogenesis. Qualitative immunohistochemical analysis revealed that CD31 and OPG expression was was strong after ALN‐ALN + PTH compared with ALN‐ALN treatment, whereas RANKL expression was weak after ALN‐ALN + PTH versus ALN‐PTH treatment. Our study showed that once‐weekly PTH combined with alendronate was beneficial in promoting the healing of fractures acquired after long‐term alendronate therapy in OVX‐induced osteoporotic rats. [ABSTRACT FROM AUTHOR]

Systemic bone loss after initial fracture contributes to an increased risk of secondary fracture. Clinical research has revealed an association between the risk of future fracture and the number or magnitude of prior fractures. However, the change in systemic bone mass after single versus multiple fractures is unknown. We used ipsilateral femur and tibia fractures as multiple fractures and a femur or tibia fracture as a single fracture to investigate the influence of single versus multiple fractures on systemic bone mass. Seventy‐two adult male C57BL/6J mice underwent transverse osteotomies of the ipsilateral femur and/or tibia with subsequent internal fixation. The dynamic change of in vivo whole‐body BMD was assessed at 4 days, 2 weeks, and 4 weeks after fracture. The microstructure of the L5 vertebral body and contralateral femur was assessed using micro‐CT (μCT) and biomechanical tests (vertebral compression test and three‐point bending test) at 2 and 4 weeks. Tartrate‐resistant acid phosphatase (TRAP) staining, sequential fluorescence labeling, and systemic inflammatory cytokines were also quantified. A greater decrease in whole‐body BMD was observed after multiple than single fractures. The trabecular bone volume fraction, trabecular number, and trabecular thickness of the L5 vertebral body were significantly reduced. There were no significant differences in cortical thickness, trabecular bone microstructure, or bone strength in the contralateral femur. At 4 days and 2 weeks, we observed significant increases in the serum levels of IL‐6 and TNF‐α. We also observed an increase in the osteoclast number of the L5 vertebral body at 4 days. These data indicate that systemic bone loss might increase with the number or severity of prior fractures, and the mechanism may be partly associated with an increased osteoclast number and a more severe inflammatory response. © 2020 American Society for Bone and Mineral Research (ASBMR). [ABSTRACT FROM AUTHOR]

This article studies the moving path following (MPF) problem where a desired path attached to a moving object must be followed. Focusing on the problem that the classical guidance vector field is not suitable for an MPF, we present a time-varying vector field guidance law, which is qualified for following a path expressed with respect to a moving target frame. Moreover, a prescribed performance method is embedded to the time-varying vector field law to further enhance the control performance. By combining the prescribed performance, the tracking errors are ensured not to exceed the predefined arbitrary small residual sets. Subsequently, the proposed guidance laws are applied to a typical MPF mission—the automatic carrier landing. An active disturbance rejection attitude controller is designed as the "low-level" controller with backstepping as the main frame. To eliminate the potential problem of external disturbances and parameter uncertainties, extended state observers are adopted in the controller. Besides, tracking differentiators are integrated with the controller to avoid complex derivative calculations in backstepping. Finally, comparative simulations are conducted, the results clarify and verify the proposed methods. [ABSTRACT FROM AUTHOR]

Objectives: Does the manipulation of the off-pump CABG (OPCAB) in patient with depressed left ventricular function is better than on-pump CABG (ONCAB) approach in in-hospital mortality and morbidities? Here we undertook a meta-analysis of the best evidence available on the comparison of primary and second clinical outcomes of the off-pump and on-pump CABG.Design: Systematic literature reviewer and meta-analysis.Data Sources: PubMed, EMBASE, Web of science and Cochrane Center Registry of Controlled Trials were searched the studies which comparing the use of the off-pump CABG(OPCAB) and on-pump CABG (ONCAB) for patients with LVD during January 1990.1 to January 2018.Eligibility Criteria: All observation studies and randomized controlled trials comparing on-pump and off-pump as main technique for multi-vessel coronary artery disease (defined as severe stenosis (>70%) in at least 2 major diseased coronary arteries) with left ventricular dysfunction(defined as ejection fraction (EF) 40% or less) were included.Data Extraction and Synthesis: Authors will screen and select the studies extract the following data, first author, year of publication, trial characters, study design, inclusion and exclusion criteria, graft type, clinical outcome, assess the risk of bias and heterogeneity. Study-specific estimates will pool through the modification of the Newcastle-Ottawa scale for the quality of study and while leave-one-out analysis will be used to detect the impact of individual studies on the robustness of outcomes.Results: Among the 987 screened articles, a total of 16 studies (32,354 patients) were included. A significant relationship between patient risk profile and benefits from OPCAB was found in terms of the 30-day mortality (odds ratio [OR], 0.84; 95% confidence interval [CI], 0.73-0.97; P = 0.02), stroke (OR, 0.69; 95% CI, 0.55-0.86; P = 0.00), myocardial infarction (MI) (OR, 0.71; 95% CI, 0.53-0.96; P = 0.02), renal failure (OR, 0.71; 95% CI, 0.55-0.93; P = 0.01), pulmonary complication (OR, 0.68; 95% CI, 0.52-0.90; P = 0.01), infection (OR, 0.67; 95% CI, 0.49-0.91; P = 0.00),postoperative transfusion (OR, 0.25; 95% CI, 0.08-0.84; P = 0.02) and reoperation for bleeding (OR, 0.56; 95% CI, 0.41-0.75; P = 0.00). There was no significant difference in atrial fibrillation (AF) (OR, 0.96;95%; CI, 0.78-1.41; P = 0.56) and neurological dysfunction (OR, 0.88; 95% CI, 0.49-1.57; P = 0.65).Conclusions: Compared with the on-pump CABG with LVD, using the off-pump CABG is a better choice for patients with lower mortality, stroke, MI, RF, pulmonary complication, infection, postoperative transfusion and reoperation for bleeding. Further randomized studies are warranted to corroborate these observational data. [ABSTRACT FROM AUTHOR]

Background: OS is the most common malignant tumor of bone which was featured with osteoid or immature bone produced by the malignant cells, and biomarkers are urgently needed to identify patients with this aggressive disease. Methods: We downloaded gene expression profiles from GEO and TARGET datasets for OS, respectively, and performed WGCNA to identify the key module. Whereafter, functional annotation and GSEA demonstrated the relationships between target genes and OS. Results: In this study, we discovered four key genes—ALOX5AP, HLA-DMB, HLA-DRA and SPINT2 as new prognostic markers and confirmed their relationship with OS metastasis in the validation set. Conclusions: In conclusion, ALOX5AP, HLA-DMB, HLA-DRA and SPINT2 were identified by bioinformatics analysis as possible prognostic markers for OS metastasis. [ABSTRACT FROM AUTHOR]

This paper presents a novel automatic carrier landing controller which holds a constant angle of attack during final approach with prescribed performance in the presence of external disturbances and carrier deck motion. Based on the nonlinear model of the aircraft, backstepping technique is adopted as the main control frame. To improve the stability during final approach, a novel control structure which maintains a constant angle of attack is proposed. By using performance constrained guidance law, the proposed controller is capable of guaranteeing trajectory tracking errors within prescribed performance, which means that the tracking errors are confined within prescribed convergence rates and maximum overshoots. Moreover, considering the deck motion of the carrier and inherent phase lag of the aircraft, deck motion compensation is included. Furthermore, nonlinear disturbance observers are introduced to eliminate the affects of unknown disturbances, while command filters are employed as well, avoiding complicated computations for time derivatives of virtual controls. Finally, simulation results clarify and verify the proposed control scheme. [ABSTRACT FROM AUTHOR]