99 research outputs found

    Ab initio study of the formation of transparent carbon under pressure

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    A body-centered tetragonal carbon (bct-Carbon) allotrope has been predicted to be a transparent carbon polymorph obtained under pressure. The structural transition pathways from graphite to diamond, M-Carbon, and bct-Carbon are simulated and the lowest activation barrier is found for the graphite-bct transition. Furthermore, bct-Carbon has higher shear strength than diamond due to its perpendicular graphene-like structure. Our results provide a possible explanation for the formation of a transparent carbon allotrope via the cold compression of graphite. We also verify that this allotrope is hard enough to crack diamond.Comment: [email protected] or [email protected]

    Identifying Critical State of Complex Diseases by Single-Sample-Based Hidden Markov Model

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    The progression of complex diseases is generally divided as a normal state, a pre-disease state or tipping point, and a disease state. Developing individual-specific method that can identify the pre-disease state just before a catastrophic deterioration, is critical for patients with complex diseases. However, with only a case sample, it is challenging to detect a pre-disease state which has little significant differences comparing with a normal state in terms of phenotypes and gene expressions. In this study, by regarding the tipping point as the end point of a stationary Markov process, we proposed a single-sample-based hidden Markov model (HMM) approach to explore the dynamical differences between a normal and a pre-disease states, and thus can signal the upcoming critical transition immediately after a pre-disease state. Using this method, we identified the pre-disease state or tipping point in a numerical simulation and two real datasets including stomach adenocarcinoma and influenza infection, which demonstrate the effectiveness of the method

    Investigation for synchronization characteristics of double cam vibrating screen

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    Aiming at the shortcomings of traditional vibrating screens with large vibration mass, a double eccentric cam self-synchronous vibrating screen is proposed. The motion differential equation of the vibrating screen system is derived by using Lagrange equation and the steady state solution is obtained. According to Hamilton principle, the synchronization condition of the vibration system is deduced, and the stability condition of the self-synchronization motion is obtained. The influencing factors of synchronization and stability are investigated by using numerical calculation and simulation analysis methods. The results show that stable self-synchronous motion of the vibration system is implemented when the synchronization and stability conditions are satisfied; the value of the stable phase difference of two cams varies in the range of (–1.5 rad, 0), and compared with the residual torque difference, the eccentricity of eccentric cams has a greater impact on the stable phase difference; additionally, a linear motion track of the vibrating screen is achieved

    Agricultural Education for Sustainable Rural Development in Developing Countries – Challenges and Policy Options

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    Governments all over the world have focused upon sustainable rural development in an organized way. Rural locations, in particular, need more economic development in order to match urban centric development. Poverty in rural areas has remained by and large, the main focal point of governments and development agencies. Sustainable rural development is the most effective way to eliminate this curse. Environment friendly growth stimulators have been provided to rural populations. This paper aims to: (a) give an insight into the linkages between the agricultural education and sustainable rural development, and (b) present strategies for sustainable rural development. Challenges in sustainable rural development for developing countries in the 21st century have also been looked into. The paper concludes that agricultural education institutions in developing countries will need to address not only immediate production needs, but also long-term food security, sustainable agriculture and rural development needs

    Sodium Valproate Inhibits the Growth of Human Cholangiocarcinoma In Vitro

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    Background. None of treatment options for Cholangiocarcinoma (CCA), including surgery, adjuvant radiotherapy and chemotherapy, and ultimately liver transplantation, have been shown to substantially improve the survival rate in patients with CCA. Valproic acid (VPA), a histone deacetylase inhibitor, has been shown to display potent antitumor effects. In this study, sodium valproate, the clinically available form of VPA, was tested for its ability to inhibit the growth of cholangiocarcinoma cells, both in vitro and in vivo. Materials and Methods. Cholangiocarcinoma cells (TFK-1, QBC939, and CCLP1) of different origins were treated with sodium valproate to determine their effects on cell proliferation and differentiation, cell cycle regulation, apoptosis, and autophagy. The in vivo effects of sodium valproate on cholangiocarcinoma growth were assessed using a xenograft mouse model injected with TFK-1 cells. Results. Sodium valproate inhibited cholangiocarcinoma cell growth by inducing cell cycle arrest, cell differentiation, and apoptosis; sodium valproate effects were independent of autophagy. Tumor growth inhibition was also observed in vivo using TFK-1 xenografts. Conclusion. The in vitro and in vivo outcomes provide preclinical rationale for clinical evaluation of sodium valproate, alone or in combination with other drugs, to improve patient outcome in cholangiocarcinoma

    The significance of wrist immobilization for endoscopic carpal tunnel release

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    BackgroundOver the years, endoscopic carpal tunnel release (ECTR) has gained significant interest as an alternative to surgery. However, no consensus has been reached on the necessity of postoperative wrist immobilization. This study aims to compare the outcomes of wrist immobilization for a period of 2 weeks to immediate wrist mobilization after ECTR.MethodsA total of 24 patients with idiopathic carpal tunnel syndrome undergoing dual-portal ECTR from May 2020 to Feb 2022 were enrolled and randomly divided into two groups postoperatively. In one group, patients wore a wrist splint for 2 weeks. In another group, wrist mobilization was allowed immediately after surgery. The two-point discrimination test (2PD test); the Semmes–Weinstein monofilament test (SWM test); the occurrence of pillar pain, digital and wrist range of motion (ROM); grip and pinch strength; the visual analog score (VAS), the Boston Carpal Tunnel Questionnaire (BCTQ) score; the Disabilities of the Arm, Shoulder, and Hand (DASH) score; and complications were evaluated at 2 weeks and 1, 2, 3, and 6 months after the surgery.ResultsAll 24 subjects finished this study with no dropouts. During the early follow-up, patients with wrist immobilization demonstrated lower VAS scores, lower occurrence of pillar pain, and higher grip and pinch strength compared with the immediate mobilization group. No significant difference was obtained between these two groups in terms of the 2PD test, the SWM test, digital and wrist ROM, BCTQ, and the DASH score. In total, two patients without splints reported transient scar discomfort. No one complained of neurapraxia, injury of the flexor tendon, median nerve, and major artery. At the final follow-up, no significant difference was found in any parameters between both groups. The local scar discomfort mentioned above disappeared and left no serious sequela.ConclusionWrist immobilization during the early postoperative period demonstrated significant pain alleviation along with stronger grip and pinch strength. However, wrist immobilization yielded no obvious superiority regarding clinical outcomes at the final follow-up
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