The spontaneous strain associated with the structural change in the metal-insulator transition in VO 2 is orders of magnitude higher than thermal expansion mismatch used in bimetallic strips. Here we show that this strain can be leveraged to thermally activate bending of crystalline VO 2-based bilayer microcantilevers at extremely large curvatures, making them suitable for thermal sensors, energy transducers and actuators with unprecedented sensitivities. The single-crystallinity, deposition conditions, and postdeposition treatments were utilized to control the metal-insulator domain structure along the cantilever, by which we achieved bending curvatures a few hundred times higher than conventional bilayer cantilevers with the same geometry.
Objectives Ferroptosis is caused by iron-dependent lipid peroxide accumulation, the sensitivity of which might be regulated by acyl-CoA synthetase long chain family member 4 (ACSL4). Non-small-cell lung cancer (NSCLC) can resist oxidative stress and reduce the sensitivity of tumor cells to ferroptosis by changing the expression of some proteins. Mechanisms involving ferroptosis sensitivity in NSCLC are not fully understood. Methods A dual-luciferase reporter assay was used to confirm a targeting relationship between long non-coding (lnc)RNA NEAT1 and ACSL4. Overexpression and silencing assays of NEAT1 function were used to determine its roles in cell death (by TUNEL staining) and lipid peroxidation (by malondialdehyde levels). Expression of ferroptosis-related proteins (SLCA11, GPX4, and TFR4) was evaluated by western blot in NSCLC cells treated or not with the ferroptosis inducer erastin. Results Erastin-induced cell death was positively correlated with ACSL4 level. NEAT1 regulated levels of ACSL4 and proteins related to the ferroptosis and classical apoptosis pathways. Levels of ACSL4, SLC7A11, and GPX4 were decreased more by NEAT1 silencing plus erastin than by erastin alone. Conclusion NEAT1 regulates ferroptosis and ferroptosis sensitivity, with the latter depending on ACSL4, suggesting that targeting NEAT1 or ACSL4 may be a viable therapeutic approach to the treatment of NSCLC.
In 2003, the Chinese Government initiated a free antiretroviral therapy (ART) program focusing on adult AIDS patients. Pediatric antiretroviral (ARV) formulations were yet unavailable. It was not until July 2005, with the initiation of a two-stage program implemented by the Chinese Ministry of Health, that pediatric formulations became accessible in China. Initially, the pediatric ART program was piloted in six provinces with the highest incidences of pediatric HIV/AIDS. The pilot stage allowed the Chinese Center for Disease Control and Prevention (CCDC) to finalize entry criteria, treatment regimen, and patient monitoring and follow-up procedures. The second stage commenced at the end of 2006 when the program was scaled-up nationally. In order to guarantee treatment of pediatric patients, extensive training in the selection of appropriate ARV drug regimen and dosage was provided to doctors, often through on-site collaboration with domestic and international experts. The CCDC simultaneously established a pediatric ARV management system and a pediatric ART information system. CD4 count and other laboratory tests are being routinely performed on these pediatric patients. By the end of June 2009, 1529 pediatric patients had received ARV under the national program. However, challenges remain. Firstly, many children infected with HIV/AIDS live in rural areas where the treatment quality is hindered by the limited number of medical facilities and skilled medical workers. Secondly, much of the pediatric ARV drug supply depends on donation. An effort needs to be made by the Chinese Government to establish China's own drug procurement and supply system.
The equation of motion of mega-sub-isolation system is established. The working mechanism of the mega-sub-isolation system is obtained by systematically investigating its dynamic characteristics corresponding to various structural parameters. Considering the number and location of the isolated substructures, a procedure to optimally design the isolator parameters of the mega-sub-isolation system is put forward based on the genetic algorithm with base shear as the optimization objective. The influence of the number and locations of isolated substructures on the control performance of mega-sub-isolation system has also been investigated from the perspective of energy. Results show that, with increase in substructure mass, the working mechanism of the mega-sub-isolation system is changed from tuned vibration absorber and energy dissipation to seismic isolation. The locations of the isolated substructures have little influence on the optimal frequency ratio but have great influence on the optimal damping ratio, while the number of isolated substructures shows great impact on both the optimal frequency ratio and damping ratio. When the number of the isolated substructures is determined, the higher the isolated substructures, the more the energy that will be consumed by the isolation devices, and with the increase of the number of isolated substructures, the better control performance can be achieved.
BackgroundTo optimize treatment regimens, we assessed human immunodeficiency virus (HIV) diversity and the prevalence of transmitted drug resistance (TDR) among men who have sex with men (MSM) in Anhui province, China.MethodsA total of 139 MSM who were newly diagnosed and antiretroviral treatment-naive were enrolled in Anhui in 2011. A partial pol fragment was amplified and sequenced, and HIV subtypes were determined by phylogenetic analyses. Surveillance/transmitted drug resistance mutations (SDRMs) were identified according to the 2009 World Health Organization (WHO) list.ResultsA total of 133 (95.7%) samples were successfully amplified and sequenced. Based on phylogenetic analyses of the pol fragment, CRF01_AE accounted for 55.6% (74/133) of the infections, followed by CRF07_BC with 32.3% (43/133), B with 5.3% (7/133), and unique recombinant forms with 6.8% (9/133). A total of 3.0% (4/133) of the subjects were found to harbor HIV variants with SDRMs, including 1.5% with NRTI-related mutations and 1.5% with NNRTI-related mutations. PI-related mutations were absent. The SDRMs included L210W (1.5%), Y181C (0.8%), and G190A (0.8%).ConclusionsIn Anhui, CRF01_AE strains contributed to most of the HIV infections among MSM, and the prevalence of TDR was relatively low in this population. Further studies should be performed to evaluate the trend of TDR among MSM in Anhui and to inform first-line antiretroviral treatment.
As urban high-rise buildings increase, a mega-sub configuration is proposed by engineers, which consists of two major structural components, a megastucture as the load-bearing main structural frame and several functional substructures for residential or other usage. This paper presents a new mega-sub isolation structure, in which substructures are designed to isolate from megastructure using special isolation devices. The equations of motion of the mega-sub isolation structure are established, and its vibration mitigation mechanism is investigated systematically using a simplified lumped mass structural model. With the increase in substructure mass, working mechanism of mega-sub isolation structure is changed from tuned vibration absorber, mid-story isolation to base isolation. In the light of theoretical studies, three steel frame specimens of four mega frame stories were tested. The experimental results show that the isolated structure and lower substructure-consolidated structure perform better than aseismic structure, and transfer functions derived from the test data support the conclusion of theoretical analysis that the control mechanism of this novel mega-sub isolation structure is similar to mid-story isolated structure in the case of the mass ratio between the substructure and the megastructure closed to 1, which is the most general situation in engineering.
Background To infer transmission direction of a HIV transmission chain is helpful not only in legal jurisdiction but also in precise intervention to prevent HIV spread. Recently, the direction of transmission is inferred by whether paraphyletic-monophyletic (PM) or a combination of paraphyletic and polyphyletic (PP) topologies is observed or not between the sequences of source and recipient in the phylogenetic tree. However, paraphyly between them often declines over time and may disappear between spouses due to bidirectional transmission after primary infection. In this study, our aim is to test the reliability of inferring HIV transmission direction between epidemiologically linked HIV-1 positive couples using whether or not paraphyly is observed in phylogenetic tree. Methods HIV quasi-species were sequenced using PCR product clones, and then Bayesian analysis of molecular sequences with MCMC was employed to construct phylogenetic relationship of env, gag, pol gene fragments of HIV-1 positive couples using BEAST software. Results Our results showed that all sequences of seven couples except pol sequences of couple 12 and 13 form their own monophyletic cluster in phylogenetic tree including the closest control sequences from GenBank or other studies on local samples, which are supported by significant Bayesian posterior probabilities more than 0.9932. Of seven couples, paraphyly is only observed in phylogenetic tree constructed with env and po l gene sequences of three couples and gag gene sequences of four couples. Paraphyly is not observed in half of HIV positive couples. Pol sequences of couple 13 is separated by Blast selected controls; pol sequences of couple 12 in phylogenetic tree is supported by a lower Bayesian posterior value. Conclusion Paraphyly relationship between sequences of donator and recipient is only observed among partial HIV-1 positive couples with epidemiological link. Phylogenetic relationship is not always the same when various gene regions of HIV are used to conduct phylogenetic analysis. The combination of phylogenetic analysis based on various gene regions of HIV and enough epidemiology investigation is essential when inferring transmission direction of HIV in a transmission chain or in one couple. However, while observed paraphyly can be used to infer transmission direction in HIV-1 positive couple, no observed paraphyly cannot deny it.
Electro-hydraulic shaking table is an essential experimental apparatus to evaluate structural performance under actual vibration condition. The control-structure interaction (CSI) between shaking table and eccentric load has lately received considerable attention for causing the accuracy degradation of shaking table test. At present, the research gap of the influence of the eccentricity of load on the CSI makes it challenging to find the CSI effects. And an effect assessment is yet to be proposed to evaluate the CSI effects, which has impeded the development of test technology. To overcome those theoretical bottlenecks, in this research, an analytical transfer function matrix of shaking table and eccentric load is established to analyze the CSI effects. The analysis is conducted under such conditions as different mass ratio (MR), moment of inertia ratio (IR), and eccentric distance ratio (ER) conditions. Through the analysis, the role of the ER is identified, the sensitivities of the MR, IR, and ER to the transfer function matrix are revealed, and the CSI effects are found. Furthermore, a novelty effect assessment is proposed to appraise whether the CSI effects can be ignored in shaking table test. And the visualization expression of the effect assessment is obtained for convenient application.
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