The aim of this study is to develop a high-efficiency single-input multiple-output (SIMO) dc-dc converter. The proposed converter can boost the voltage of a low-voltage input power source to a ...controllable high-voltage dc bus and middle-voltage output terminals. The high-voltage dc bus can take as the main power for a high-voltage dc load or the front terminal of a dc-ac inverter. Moreover, middle-voltage output terminals can supply powers for individual middle-voltage dc loads or for charging auxiliary power sources (e.g., battery modules). In this study, a coupled-inductor-based dc-dc converter scheme utilizes only one power switch with the properties of voltage clamping and soft switching, and the corresponding device specifications are adequately designed. As a result, the objectives of high-efficiency power conversion, high step-up ratio, and various output voltages with different levels can be obtained. Some experimental results via a kilowatt-level prototype are given to verify the effectiveness of the proposed SIMO dc-dc converter in practical applications.
The mechanical characteristics presented in cancer microenvironment are known to have pivotal roles in cancer metastasis, which accounts for the leading cause of death from malignant tumors. However, ...while a uniformly distributed high interstitial fluid pressure (IFP) is a common feature in solid tumors, the effects of high IFP on the motility and invasiveness of cancer cells remain obscure. Using cell-culture devices that simulated increased IFP conditions by applying hydrostatic pressure (HP) ranging from 0 to 20 mm Hg to the cells, we found that the elevated HPs increased the migration speeds, invasiveness, cell volume, filopodial number and aquaporin-1 (AQP1), Snail and vinculin expression levels, as well as phosphorylation of caveolin-1 and extracellular signal-regulated kinase1/2 (ERK1/2), in the lung cancer cells CL1-5 and A549. The increases of migration speed and cell volume correlated temporally with the increase of AQP1 expression. The elevated HP-induced migration acceleration was hindered by AQP1 knockdown using small interfering RNA (siRNA) transfection. Inhibition of ERK1/2 phosphorylation using the mitogen-activated protein kinase kinase inhibitor PD98059 abrogated the elevated HP-induced AQP1 upregulation and migration acceleration in the cancer cells. Caveolin-1 knockdown by siRNA transfection attenuated the HP-induced, ERK1/2-depedent AQP1 upregulation and migration acceleration. Further biochemical studies revealed that the caveolin-1 activation-driven ERK1/2 signaling is mediated by Akt1/2 phosphorylation. By contrast, the elevated HPs had negligible effects on the migration speed and volume of normal bronchial epithelial cells. These results disclose a novel mechanism relating high IFP to the invasiveness of cancer cells and highlight potential targets to impede cancer spreading.
Strontium ranelate (SrR) is an oral pharmaceutical agent for osteoporosis. In recent years, numerous unwanted side effects of oral SrR have been revealed. Therefore, its clinical administration and ...applications are limited. Hereby, this study aims to develop, formulate, and characterize an effective SrR carrier system for spinal bone regeneration.
Herein, glycol chitosan with hyaluronic acid (HA)-based nanoformulation was used to encapsulate SrR nanoparticles (SrRNPs) through electrostatic interaction. Afterward, the poly(ethylene glycol) diacrylate (PEGDA)-based hydrogels were used to encapsulate pre-synthesized SrRNPs (SrRNPs-H). The scanning electron microscope (SEM), TEM, rheometer, Fourier-transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS) were used to characterize prepared formulations. The rabbit osteoblast and a rat spinal decortication models were used to evaluate and assess the developed formulation biocompatibility and therapeutic efficacy.
In vitro and in vivo studies for cytotoxicity and bone regeneration were conducted. The cell viability test showed that SrRNPs exerted no cytotoxic effects in osteoblast in vitro. Furthermore, in vivo analysis for new bone regeneration mechanism was carried out on rat decortication models. Radiographical and histological analysis suggested a higher level of bone regeneration in the SrRNPs-H-implanted groups than in the other experimental groups.
Local administration of the newly developed formulated SrR could be a promising alternative therapy to enhance bone regeneration in bone-defect sites in future clinical applications.
Poly(vinylidene fluoride) (PVDF) was extensively used as the filtration material because of its stable thermal and chemical capabilities. However, hydrophobic surface of PVDF membrane induces the ...restriction for its manufacturing uses. In light of this, the plasma at atmospheric pressure was used for the PVDF membrane surface treatment with argon/methane gas mixture in this paper. The variation in hydrophilicity of the plasma-treated PVDF membrane was analyzed by the contact angle analysis. It shows that this plasma is operative in membrane surface modification. The argon/methane gas mixture cyclonic plasma-treated PVDF membrane also showed the enhanced filtration behavior rather than the untreated PVDF membrane.
Antipyretic and toxin-eliminating traditional Chinese herbs are believed to possess antiviral activity. In this study, we screened extracts of 22 herbs for activity against enterovirus 71 (EV71). We ...found that only extracts of Houttuynia cordata Thunb. could neutralize EV71-induced cytopathic effects in Vero cells. The 50% inhibitory concentration of H. cordata extract for EV71 was 125.92 +/- 27.84 mug/ml. Antiviral screening of herb extracts was also conducted on 3 genotypes of EV71, coxsackievirus A16 and echovirus 9. H. cordata extract had the highest activity against genotype A of EV71. A plaque reduction assay showed that H. cordata extract significantly reduced plaque formation. Viral protein expression, viral RNA synthesis and virus-induced caspase 3 activation were inhibited in the presence of H. cordata extract, suggesting that it affected apoptotic processes in EV71-infected Vero cells by inhibiting viral replication. The antiviral activity of H. cordata extract was greater in cells pretreated with extract than those treated after infection. We conclude that H. cordata extract has antiviral activity, and it offers a potential to develop a new anti-EV71 agent.
Hot QCD White Paper Arslandok, M; Bass, S A; Bautista, I ...
arXiv (Cornell University),
03/2023
Paper, Journal Article
Odprti dostop
Hot QCD physics studies the nuclear strong force under extreme temperature and densities. Experimentally these conditions are achieved via high-energy collisions of heavy ions at the Relativistic ...Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC). In the past decade, a unique and substantial suite of data was collected at RHIC and the LHC, probing hydrodynamics at the nucleon scale, the temperature dependence of the transport properties of quark-gluon plasma, the phase diagram of nuclear matter, the interaction of quarks and gluons at different scales and much more. This document, as part of the 2023 nuclear science long range planning process, was written to review the progress in hot QCD since the 2015 Long Range Plan for Nuclear Science, as well as highlight the realization of previous recommendations, and present opportunities for the next decade, building on the accomplishments and investments made in theoretical developments and the construction of new detectors. Furthermore, this document provides additional context to support the recommendations voted on at the Joint Hot and Cold QCD Town Hall Meeting, which are reported in a separate document.
Walking as a basic ability of human beings enables independent activity. For people with a walking disability, however, walking can be very difficult and often requires a walker. Most mechanical or ...mechanical-electrical walkers available today come with various defects and fail to offer satisfactory movement support. The strategy to maintain a constant distance between the user and walker, as proposed by Goro, has good potential for implementing an ideal walker, but it still has some problems in terms of reference points to the human body and its framework design. Thus, the purpose of this research is to solve these problems by developing a walker with dynamic support and verify its clinical feasibility. In this study, a specific relationship between the person's ankle and the walker position was identified. Consequently, the distance between the ankle and walker was detected and then used to control walker movement. In addition, a powered transmission device and omni-directional wheels were utilized to ensure sturdy support and good turning functionality. The results of the experiments in this study indicated the maximal force of pushing forward of this new walker was 58.3N, or 5-8 times as high as a 4-wheeled walker, and its lateral pushing force was up to 84N. In terms of turning functionality, the new walker had a radial range of 12-13.1 cm, which was the same as that of the 4-wheeled walker, and there was an improvement in terms of functionality compared to Goro's walker.
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