•Postbuckling responses of multi-directional FGM plates with complex cutouts are investigated.•This method combines NURBS-based Isogeometric approach and Finite Cell Method.•The Finite Cell Method ...can flexible and efficient handle complex cutouts.•The cylinder arc-length method along with initial geometric imperfections is applied to track the postbuckling paths.
Geometric modeling and numerical analysis of multi-directional FGM (Functionally Graded Material) plate, whose material properties grade continuously both in its thickness and in-plane directions, are increasingly required. In this work, postbuckling behavior of this type of plates with multiple cutouts is, for the first time, numerically investigated through the combination of NURBS-based IGA (IsoGeonetric Analysis) and FCM (Finite Cell Method). The nonlinear deformation of plate is determined by TSDT (Third-order Shear Deformation Theory) and von Kármán nonlinear assumptions without the requirement of SCFs (shear correction factors). Besides, the higher continuity advantage of NURBS basis functions can easily meet the C1-continuous requirement of the displacement field. The main contribution is introducing the FCM to deal with the influence of complex cutouts on the postbuckling characteristics. The geometric interfaces of the cutouts are approached and approximated by adaptive quadrature procedure in the distinguished cut elements. The advantage of this implementation is that the previously tricky process of representing the geometry of perforated plate with multiple NURBS patches can be eliminated, which naturally avoids the imposition of C1-continuity condition across the patch boundaries. The cylinder arc-length method combined with modified Newton–Raphson iteration algorithm, which takes into account of the initial geometric imperfections, is applied to implement geometrically nonlinear stability analysis and track the postbuckling paths. The effectiveness and reliability of the presented method are verified with available solutions of isotropic and conventional perfect FGM plates. Subsequently, a series of factors, including material volume fraction, length-to-thickness ratio, boundary condition, cutout size, etc., affecting the postbuckling responses of multi-directional perforated FGM plates are considered and investigated.
Ultrathin, transparent, and flexible devices with multifunctionalities are indispensable for emerging technologies. However, the related reports are very few, and the efficiency is rather limited ...owing to material restriction and complicated fabrication processes. In this work, a light-responsive white light-emitting diode (LED) with ultrathin, transparency, dual-side emission, and flexible characteristics based on graphene-insulator-semiconductor (GIS) structure is demonstrated. The GIS light-responsive white LED consists of highly luminescent histidine-doped two-dimensional molybdenum disulfide (MoS2) quantum disks, an Al2O3 insulating layer, and a graphene transparent electrode. By applying an external bias, it enables to generate white light emission with a high emission efficiency of around 9%. The underlying mechanism can be well understood by quantum tunneling. In addition, the GIS structure also shows good durability under a bending test of 200 cycles. Unlike conventional white LEDs, which always required multiple emissive layers, our GIS light-responsive LED is only based on a single emissive material of histidine-doped MoS2 quantum disks, which possess a broadband emission property and low toxicity. Therefore, with the superior multiple functionalities, our study shown here is very useful for the future development of next-generation optoelectronic devices.
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Conventional treatments for functional dyspepsia (FD) are limited. Herbal medicine (HM) use is prevalent despite unclear comparative effectiveness among different formulae.
This network meta-analysis ...(NMA) aimed to evaluate the comparative effectiveness of HM formulae for FD against placebo.
Seven international and Chinese databases were searched for randomised controlled trials (RCTs) on HM versus placebo. Risk of bias among RCTs was assessed using Cochrane Risk-of-Bias Tool 2. Data from RCTs were extracted for random-effect pairwise meta-analyses. NMAs were performed to evaluate the comparative effectiveness of HM formulae. GRADE partially contextualised framework was adopted to facilitate NMA result interpretation.
Twelve different HM formulae were identified from fifteen RCTs of mediocre quality. At 8-week follow-up, pairwise meta-analyses indicated that HM was superior to placebo in alleviating global symptoms (pooled risk difference (RD): 0.20; 95% confidence interval (CI): 0.11–0.29), with effect size larger than the minimally clinically important difference of 0.20 RD. Sensitivity analysis showed no significant impact on results attributable to risk of bias. NMAs demonstrated that Xiao Yao Pill and Modified Ban Xia Xie Xin Decoction probably have a large beneficial effect on alleviating global symptoms (RD: 0.37; 95% CI: 0.03–0.99) and postprandial fullness (standardised mean difference: −0.93; 95% credible interval: −1.61 to −0.06), respectively. No serious adverse events were reported.
Xiao Yao Pill and Modified Ban Xia Xie Xin Decoction may be considered as an alternative among patients unresponsive to conventional treatments. The comparative effectiveness of these two formulae should be evaluated in future trials.
Three types of water pins are currently used in the water-assisted injection molding technologies to mold plastic parts, including orifice, ring and piercing type pins. Nevertheless, the former two ...types of pins have the disadvantages of a low flow rate and high pressure drop, while the drawbacks for the latter type are that timing the piercing pin into the cavity is a challenge and the cost of a mold is high. This report describes the development a novel high flow rate water pin for water-assisted injection molding of plastic parts. The pin, which consists of a sintered porous surface outlet, has been tested on parts with two different geometries: a plate with a channel across the center and a float-shaped tube part. The experimental results suggests that the proposed water injection pin can mold parts of a large size with a more uniform residual wall thickness distribution.
Both the Yangtze River Delta (YRD) and the Pearl River Delta (PRD), the two most rapidly developing areas in eastern China, have suffered from serious air pollution, and thus, numerous investigations ...were devoted to studying these problems. Other areas in eastern China have received less attention despite similar rapid development in their industries and economy. In this study, we analyzed air‐quality data from Kinmen Island (24°27′26″N, 118°19′36″E) located off Fujian Province and between the two above‐mentioned deltas. Our results clearly show that the study area is experiencing serious air quality deterioration. Particularly, high levels of suspended particulate matter (PM) were observed during winter, when the northeasterly monsoon prevails. For example, concentrations of wintertime PM10 (particles ≤ 10 μm in diameter) frequently exceeded 100 μg/m3 in the last three years. In addition to the air‐quality data analysis, aerosol samples were collected between 22 November 2007 and 6 March 2008 and subjected to chemical analyses of various species. Our findings show that the three principal PM components include organic, mineral, and sulfate species with moderate to minor fractions of nitrate, sea salt, elemental carbon, and trace metal oxides. The high PM levels observed over the island may be partly attributed to the transport from a mixed‐type industrial area located ∼40 km northeast of Kinmen. Our study could partially fill the air quality data gap between the YRD and PRD regions, and highlight the alarming fact that air pollution has gradually expanded along eastern China's coastal zone.
The Pearl River Delta (PRD) is one of the most industrialized and urbanized regions in China. With rapid growth of the economy, it is suffering from deteriorating air quality. Non-methane ...hydrocarbons (NMHCs) were investigated at urban and suburban sites in Guangzhou (GZ), a rural site in PRD and a clean remote site in South China, in April 2005. Additional roadside samples in GZ and Qingxi (QX, a small industrial town in PRD), ambient air samples at the rooftop of a printing factory in QX and exhaust samples from liquefied petroleum gas (LPG)—fueled taxis in GZ were collected to help identify the source signatures of NMHCs. A large fraction of propane (47%) was found in exhaust samples from LPG-fueled taxis in GZ and extremely high levels of toluene (2.0–3.1
ppmv) were found at the rooftop of the printing factory in QX. Vehicular and industrial emissions were the main sources of NMHCs. The effect of vehicular emission on the ambient air varied among the three PRD sites. The impact of industrial emissions was widespread and they contributed greatly to the high levels of aromatic hydrocarbons, especially toluene, at the three PRD sites investigated. Leakage from vehicles fueled by LPG contributed mainly to the high levels of propane and
n-butane at the urban GZ site. Ethane and ethyne from long-range transport and isoprene from local biogenic emission were the main contributors to the total hydrocarbons at the remote site. Diurnal variations of NMHCs showed that the contribution from vehicular emissions varied with traffic conditions and were more influenced by fresh emissions at the urban site and by aged air at the suburban and rural sites. Isoprene from biogenic emission contributed largely to the ozone formation potential (OFP) at the remote site. Ethene, toluene and
m/
p-xylene were the main contributors to the OFP at the three PRD sites.
Abstract
Objective
Air pollution had been reported to be associated with the reproductive health of women. However, the association of particulate matter (PM) and acid gases air pollution with ...premenstrual syndrome (PMS) warrants investigation. This study investigated the effects of air pollution on PMS risk.
Population
We combined data from the Taiwan Air Quality-Monitoring Database and the Longitudinal Health Insurance Database. In total, an observational cohort of 85 078 Taiwanese women not diagnosed as having PMS.
Methods
Air pollutant concentrations were grouped into four levels based on the concentration quartiles of several types of air pollutants.
Main outcome measures
We then applied univariable and multivariable Cox proportional hazard regression models to assess PMS risk in association with each pollutant type.
Results
Women exposed to Q4-level SO2 exhibited a 7.77 times higher PMS risk compared with those to Q1-level SO2 (95% confidence interval CI = 6.22–9.71). Women exposed to Q4-level NOx exhibited a 2.86 times higher PMS risk compared with those exposed to Q1-level NOx (95% CI = 2.39–3.43). Women exposed to Q4-level NO exhibited a 3.17 times higher PMS risk compared with women exposed to Q1-level NO (95% CI = 2.68–3.75). Finally, women exposed to Q4-level PM with a ≤2.5-µm diameter (PM2.5) exhibited a 3.41 times higher PMS risk compared with those exposed to Q1-level PM2.5 (95% CI = 2.88–4.04).
Conclusions
High incidences of PMS were noted in women who lived in areas with higher concentrations of SO2, NOx, NO, NO2 and PM2.5.
Telomeres, TTAGGGn DNA repeat sequences located at the ends of eukaryotic chromosomes, play a pivotal role in aging and are targets of DNA damage response. Although we and others have demonstrated ...presence of short telomeres in genetic cardiomyopathic and heart failure cardiomyocytes, little is known about the role of telomere lengths in cardiomyocyte. Here, we demonstrate that in heart failure patient cardiomyocytes, telomeres are shortened compared to healthy controls. We generated isogenic human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) with short telomeres (sTL-CMs) and normal telomeres (nTL-CMs) as model. Compared to nTL-CMs, short telomeres result in cardiac dysfunction and expression of senescent markers. Using Hi-C and RNASeq, we observe that short telomeres induced TAD insulation decrease near telomeric ends and this correlated with a transcription upregulation in sTL-CMs. FOXC1, a key transcription factor involved in early cardiogenesis, was upregulated in sTL-CMs and its protein levels were negatively correlated with telomere lengths in heart failure patients. Overexpression of FOXC1 induced hiPSC-CM aging, mitochondrial and contractile dysfunction; knockdown of FOXC1 rescued these phenotypes. Overall, the work presented demonstrate that increased chromatin accessibility due to telomere shortening resulted in the induction of FOXC1-dependent expression network responsible for contractile dysfunction and myocardial senescence.
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