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The Omicron variant has become the dominant COVID-19 variant worldwide due to its rapid and cryptic spread; therefore, successful early warning is of great importance to be able to control epidemics in their early phase, before developing into large outbreaks. COVID-19-related Baidu search index, which reflects human behavior to a certain degree, was used to retrospectively detect the warning signs for Omicron variant outbreaks in China in 2022. The characteristics and effects of warning signs were analyzed in detail. We detected the presence of early warning signs (both high and low thresholds) and found that these occurred 4-7 days earlier than traditional epidemiological surveillance and20 days earlier than the implementation of the local "lockdown" policy. Compared with the "high threshold" warning, the early warning effect of the "low threshold" is also vital because it indicates a complacency about epidemic prevention and control. However, there is obvious heterogeneity in the optimal threshold for detecting early warning signs and their distribution in different cities. Multi-source and multi-point early warning systems should be established via combining internet-based big data in the future to conduct effective and early real-time warning. This would create precious time for the early control of COVID-19 outbreaks. This article is protected by copyright. All rights reserved.

In March 2022, the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) surged during the Coronavirus Disease 2019 (COVID-19) pandemic in Shanghai, but over 90% of patients were mild. This study included 1139 COVID-19 patients mildly infected with the Omicron variant of SARS-CoV-2 in Shanghai from May 1 to 10, 2022, aiming to clarify the demographic characteristics and clinical symptoms of patients with mild Omicron infection. The clinical phenotypes of Omicron infection were identified by model-based cluster analysis to explore the features of different clusters. The median age of the patients was 41.0 years [IQR: 31.0-52.0 years] and 73.0% were male. The top three clinical manifestations are cough (57.5%), expectoration (48.3%), and nasal congestion and runny nose (43.4%). The prevalence of nasal congestion and runny nose varied significantly across the doses of vaccinations, with 23.1% in the unvaccinated population and 30%, 45.9%, and 44.3% in the 1-dose, 2-dose and 3-dose vaccinated populations, respectively. In addition, there were significant differences for fever (23.1%, 26.0%, 28.6%, 18.4%), head and body heaviness (15.4%, 14.0%, 26.7%, 22.4%), and loss of appetite (25.6%, 30.0%, 33.6%, 27.7%). The unvaccinated population had a lower incidence of symptoms than the vaccinated population. Cluster analysis revealed that all four clusters had multisystemic symptoms and were dominated by both general and respiratory symptoms. The more severe the degree of the symptoms was, the higher the prevalence of multisystemic symptoms will be. The Omicron variant produced a lower incidence of symptoms in mildly infected patients than previous SARS-CoV-2 variants, but the clinical symptoms caused by the Omicron variant are more complex, so that it needs to be differentiated from influenza.

Objective Dexmedetomidine (DEX) exhibits neuroprotective effects as a multifunctional neuroprotective agent in numerous neurological disorders. However, in traumatic brain injury (TBI), the molecular mechanisms of these neuroprotective effects remain unclear. The present study investigated whether DEX, which has been reported to exert protective effects against TBI, could attenuate neuroinflammatory‐induced apoptosis and clarified the underlying mechanisms. Methods A weight‐drop model was established, and DEX was intraperitoneally injected 30 min after inducing TBI in rats. The water content in the brain tissue was measured. Terminal deoxynucleotidyl transferase‐mediated dUTP nick‐end labeling (TUNEL) assays were performed on histopathological tissue sections to evaluate neuronal apoptosis. Enzyme‐linked immunosorbent assay and PCR were applied to detect the levels of the inflammatory factors, TNF‐α, IL‐1β, IL‐6, and NF‐κB. Results TBI–challenged rats exhibited significant neuronal apoptosis, which was characterized via the wet‐to‐dry weight ratio, neurobehavioral functions, TUNEL assay results and the levels of cleaved caspase‐3, Bax upregulation and Bcl‐2, which were attenuated by DEX. Western blot, immunohistochemistry, and PCR results revealed that DEX promoted Nrf2 expression and upregulated expression of the Nrf2 downstream factors, HO‐1 and NQO‐1. Furthermore, DEX treatment markedly prevented the downregulation of inflammatory response factors, TNF‐α, IL‐1β and NF‐κB, and IL‐6. Interpretation Administering DEX attenuated inflammation‐induced brain injury in a TBI model, potentially via the Nrf2 signaling pathway.

Breviscapine (BVP) has been widely used in the treatment of several systemic diseases, including those of the cardiovascular and cerebrovascular systems. But, few studies have looked at the neuroprotective effects of BVP and its potential effect in treating traumatic brain injury (TBI). The present study investigated the neuroprotective effect of BVP following TBI and illuminated the underlying mechanism. The weight drop-induced closed diffuse traumatic brain injury method was used to induce TBI in rats. BVP was injected intraperitoneally 30 minutes after TBI. Neurologic scores were performed to measure behavioral outcomes. Nissl staining and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assays were performed on histopathologic tissue sections to evaluate neuronal apoptosis. The nuclear factor erythroid 2-related factor 2 (Nrf2) and its related downstream proteins, including heme oxygenase-1 (HO-1) and quinine oxidoreductase-1 (NQO1) were detected with Western blots. BVP treatment alleviated or attenuated TBI-induced neuron cell apoptosis and improved neurobehavioral functions through the upregulated expression of Nrf2 and its related downstream proteins. This study, using the drug, BVP, we present new mechanisms responsible for neuronal apoptosis in TBI with possible involvement of the Nrf2 pathway.

There is growing evidence that climatic factors could influence the evolution of the current COVID‐19 pandemic. Here, we build on this evidence base, focusing on the southern hemisphere summer and autumn period. The relationship between climatic factors and COVID‐19 cases in New South Wales, Australia was investigated during both the exponential and declining phases of the epidemic in 2020, and in different regions. Increased relative humidity was associated with decreased cases in both epidemic phases, and a consistent negative relationship was found between relative humidity and cases. Overall, a decrease in relative humidity of 1% was associated with an increase in cases of 7–8%. Overall, we found no relationship with between cases and temperature, rainfall or wind speed. Information generated in this study confirms humidity as a driver of SARS‐CoV‐2 transmission.

Previous research has identified a relationship between climate and occurrence of SARS‐CoV and MERS‐CoV cases, information that can be used to reduce the risk of infection. Using COVID‐19 notification and postcode data from New South Wales, Australia during the exponential phase of the epidemic in 2020, we used time series analysis to investigate the relationship between 749 cases of locally acquired COVID‐19 and daily rainfall, 9 a.m. and 3 p.m. temperature, and 9 a.m. and 3 p.m. relative humidity. Lower 9 a.m. relative humidity (but not rainfall or temperature) was associated with increased case occurrence; a reduction in relative humidity of 1% was predicted to be associated with an increase of COVID‐19 cases by 6.11%. During periods of low relative humidity, the public health system should anticipate an increased number of COVID‐19 cases.

Noncoding RNAs, including long non-coding RNAs (lncRNAs) and microRNAs, are involved in the development of neuropathic pain. Currently, we investigated that lncRNA X inactive-specific transcript (XIST) and toll-like receptor 5 (TLR5) were greatly upregulated in chronic constriction injury rat models, whereas miR-154-5p (microRNA-154-5p) was significantly downregulated. Bioinformatics analysis was used to predict miR-154-5p as a target gene of XIST, and dual-luciferase reporter tests proved the correlation between them. We observed that miR-154-5p was negatively modulated by XIST in vitro. XIST overexpression markedly induced neuropathic pain development in rats with chronic constriction injury, whereas the upregulation of miR-154-5p could reverse this phenomenon. Furthermore, TLR5 was demonstrated to be a target gene of miR-154-5p by using bioinformatics predictions. miR-154-5p negatively regulated TLR5 expression in vitro, and TLR5 was able to promote neuropathic pain development. In addition, overexpressing miR-154-5p can reverse the role of TLR5 neuropathic pain in vivo. Taken these together, we indicated that XIST could increase TLR5 expression by acting as a sponge of miR-154-5p in neuropathic pain development. This study revealed that XIST can contribute to neuropathic pain progression in rats through decreasing miR-154-5p and increasing TLR5. The XIST/miR-154-5p/ TLR5 axis can be provided as a novel therapeutic target in treating neuropathic pain.

Extensive research papers of three-dimensional computational techniques are widely used for the investigation of human brain pathophysiology. Eddy current analyzing could provide an indication of conductivity change within a biological body. A significant obstacle to current trend analyses is the development of a numerically stable and efficiency-finite element scheme that performs well at low frequency and does not require a large number of degrees of freedom. Here, a custom finite element method (FEM) solver based on edge elements is proposed using the weakly coupled theory, which separates the solution into two steps. First, the background field (the magnetic vector potential on each edge) is calculated and stored. Then, the electric scalar potential on each node is obtained by FEM based on Galerkin formulations. Consequently, the electric field and eddy current distribution in the object can be obtained. This solver is more efficient than typical commercial solvers since it reduces the vector eddy current equation to a scalar one, and reduces the meshing domain to just the eddy current region. It can therefore tackle complex eddy current calculations for models with much larger numbers of elements, such as those encountered in eddy current computation in biological tissues. An example is presented with a realistic human brain mesh of 2 million elements. In addition, with this solver, the equivalent magnetic field induced from the excitation coil is applied, and therefore there is no need to mesh the excitation coil. In combination, these significantly increase the efficiency of the solver. Bioelectromagnetics. 39:604-616, 2018. © 2018 Wiley Periodicals, Inc.

AIM To date, reported associations between methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and preterm delivery are conflicting. The present meta-analysis summarized the existing evidence and evaluated these associations. METHODS Eligible studies were retrieved from Medline (PubMed), EMBASE, the Chinese Biomedical Literature Database and the Cochrane Library. We calculated pooled odds ratios (ORs) and 95% confidence interval (CIs) within five genetic models using either random-effects or fixed-effects models dependent on study heterogeneity. Potential publication bias was assessed using a Begg's test. Sensitivity analysis was performed to evaluate the stability of the results. RESULTS Thirteen studies involving 4816 mothers who experienced preterm delivery and 34 506 normal controls were finally included. Significant associations between MTHFR C677T polymorphism and the risk of preterm delivery were detected overall (ORT/C = 1.34, 95% CI 1.12-1.61; ORTT/CC = 1.60, 95% CI 1.21-2.11; ORCT/CC = 1.33, 95% CI 1.07-1.65; ORTT/(CC + CT) = 1.41, 95% CI 1.11-1.78; OR(TT + CT)/CC = 1.36, 95% CI 1.11-1.66) and in an Asian population (ORT/C = 1.80, 95% CI 1.24-2.62; ORTT/CC = 2.13, 95% CI 1.27-3.57; ORCT/CC = 1.93, 95% CI 1.37-2.71; OR(TT + CT)/CC = 2.03, 95% CI 1.49-2.77). Negative associations of the A1298C polymorphism were only observed among Asian pregnant women (ORC/A = 0.66, 95% CI 0.50-0.88; ORCC/AA = 0.10, 95% CI 0.02-0.53; ORCC/(AA + AC) = 0.11, 95% CI 0.02-0.57; OR(CC + AC)/AA = 0.68, 95% CI 0.49-0.94). CONCLUSIONS MTHFR 677 T may play a significant role in regard to the risk of preterm delivery, especially in the Asian population.

Aberrant mechanical properties and immunosuppression are the two key factors that limit the antitumor efficacy of T cell immune checkpoint blockade inhibitors, e.g., programmed cell death‐1 antibody (PD‐1 Ab), against solid tumors in the clinic. This study leverages hyperbaric oxygen (HBO) for the first time to address these two issues and reports the PD‐1‐Ab‐mediated immune responses against various stroma‐rich solid malignancies. The results demonstrate that HBO promoted PD‐1 Ab delivery and T cells infiltration into tumor parenchyma by depleting the extracellular matrix's main components, such as collagen and fibronectin. Furthermore, HBO disrupts hypoxia‐mediated immunosuppression and helps PD‐1 Ab trigger robust cytotoxic T lymphocytes and long‐lasting immunological memory to inhibit tumor relapses. Such enhanced immune responses are effective in solid tumors from rodents and the cancer cells from hepatocellular carcinoma patients. The results illustrate that HBO bolsters antitumor efficacy of PD‐1 Ab, and the HBO–PD‐1 Ab combination is a promising stroma‐rich solid tumors’ treatment in the clinic., It is revealed that hyperbaric oxygen (HBO) depleted extracellular matrix's major components, including collagen and fibronectin, thereby promoting the delivery of PD‐1 Ab and the infiltration of T cell into tumor parenchyma. Furthermore, HBO disrupted hypoxia‐mediated immunosuppression and helped PD‐1 Ab trigger robust cytotoxic T lymphocytes and long‐lasting immunological memory effect for the inhibition of tumor relapses.

Mullite whiskers are potential candidates for improving the mechanical and thermal properties of ceramic, glass, and composite material. In this work, well-developed whisker-shaped mullite has been produced by adding tribasic calcium phosphate (Ca3(PO4)2) into kaolin before calcining in air. In the raw kaolin, rod-like mullite crystal of ~0.5-1.0 μm length and ~0.05-0.2 μm diameter formed at 1350°C, and mullite whiskers were not be observed; however, by doping 6 wt% Ca3(PO4)2 into kaolin, mullite whiskers of ~5.5 μm length and ~0.05-0.10 μm diameter grew at 1250°C. The formation of high aspect ratio of mullite whiskers can probably be explained by the synergistic effect of P2O5 and CaO, resulting in the formation of liquid phase with a relatively higher content of Si and a lower viscosity at low temperature of 1250°C, which facilitates the growth of mullite displaying acicular morphology. The results are of interest in producing high aspect ratio of mullite whiskers from kaolin at reduced calcination temperatures.

A simple and convenient copper-catalyzed direct oxyphosphorylation of enamides with P(O)-H compounds and dioxygen has been developed under mild conditions. This methodology can allow the synthesis of a series of valuable β-ketophosphine oxides/β-ketophosphonates in moderate to good yields with a broad substrate scope simply by using readily-available starting materials.

Carbon quantum dots (CQDs), as a new class of carbon nanomaterials, have attracted considerable interest because of their low cost, low toxicity, chemical inertness, superiority in water solubility, ease of functionalization and simple synthetic routes. In recent years, the excellent light harvesting capability and unique photo-induced electron transfer ability have greatly inspired the perspectives of CQDs in photocatalysis applications. Herein, a comprehensive overview on the recent progresses of CQDs with an emphasis on their applications in photocatalysis is presented. Strategies that have been employed to increase their photocatalytic activities are discussed in detail, including doping, surface modulation, and design of composite structures. Moreover, some perspectives on the challenges and new directions are proposed to stimulate further research into this exciting and promising field.

Introduction The beneficial health effects of traditional Chinese medicines are often attributed to their potent antioxidant activities, usually established in vitro. However, these wet chemical methods for determining antioxidant activities are time-consuming, laborious, and expensive. Objectives This study was conducted to establish a rapid determination of antioxidant activity of Radix Scutellariae using near-infrared (NIR) and mid-infrared (MIR) spectroscopy. Material and methods Antioxidant capabilities were evaluated using 2,2-diphenyl-1-picrylhydrazyl hydrazyl (DPPH) and oxygen radical absorbance capacity (ORAC) assays. The total flavonoid contents (TFCs) of Radix Scutellariae were measured by the aluminium chloride colorimetric method. The same sample was then scanned using NIR and MIR spectroscopy. Chemometrics analysis using partial least-squares (PLS) regression was performed to establish the models for predicting the antioxidant activities of Radix Scutellariae. Results A better predictive performance was achieved using PLS models based on NIR data. The determination coefficient (R2) and the residual predictive deviation (RPD) for the validation set were 0.9298 and 2.84 for DPPH, and 0.9436 and 2.66 for TFCs, respectively. MIR-PLS algorithms gave a slightly lower reliability (R2 = 0.9090 and 0.9374, RPD = 2.01 and 2.42, for DPPH and TFC, respectively). Very comparable results for ORAC were obtained with the two methods. Conclusion The developed spectroscopic method can be successfully applied in high-throughput screening of the antioxidant capability of Radix Scutellariae samples. It can also be a viable and advantageous alternative to laborious chemical procedures. Copyright © 2015 John Wiley & Sons, Ltd.

Trifluoropropylmethylsiloxane–phenylmethylsiloxane gradient copolysiloxanes were synthesized by anionic and cationic ring-opening polymerization (ROP) of 1,3,5-tris(trifluoropropylmethyl)cyclotrisiloxane ( D3F) and phenylmethylcyclotrisiloxane ( D3Ph). The analysis of reactivity ratios revealed that the reactivity of D3F toward anionic ROP was higher than that of D3Ph; however, D3F exhibited lower reactivity compared with D3Ph during the cationic ROP. AB and BAB type gradient copolymers were obtained because of a difference in the reactivity of the monomers. The microstructure of copolymers was characterized by 29Si NMR spectroscopy, gel permeation chromatography, and differential scanning calorimetry. Furthermore, the mechanism for kinetics inverse of copolymerization was proposed based on the results of the optimized molecular configuration. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015

Insight is a salient psychotherapeutic progress but has rarely been measured in a controlled experimental setting. This study aimed to assess whether textual micro-counseling dialogue could validly evoke insight and to explore the characteristics of insight. The guessing riddle of cognitive psychology was used as a reference of the experimental paradigm. Specifically, textual micro-counseling dialogues applying cognitive restructuring techniques were presented. The participant first read a description of a psychological distress ("problem") and then an explanation ("solution"). Zero-, low-, and high-restructuring solutions were randomly matched to the problems and it was expected that they would trigger different levels of insight experiences. Experts and students evaluated the adaptability and emotional valence of problems, and the insightfulness, novelty, adaptability, and emotional valence of solutions. For both experts and students, different intensities of insightfulness were produced across high-, low- and zero-restructuring solutions. Novelty significantly discriminated the high-restructuring solutions from the other two solution types. Adaptability and emotional valence could discriminate the high- and low-restructuring solutions types from the zero-restructuring solution. Insightfulness had high correlations with novelty and adaptability. These results indicated that textual micro-counseling dialogues with a high-restructuring solution could validly produce the greatest insightfulness and the features of high-restructuring solutions may have reference meaning for improving psychotherapeutic effect.

Raspberry-like SiO2@Polymer composite particles, prepared by one-pot Pickering emulsion polymerization in aqueous medium, were used to reinforce silicone rubber. Bearing both polymer moieties and Si-OH groups on the surface, these raspberry-like particles were better dispersed in the silicone rubber matrix; therefore the mechanical performance of the resultant particle - silicone rubber composites was significantly enhanced. With 25 phr SiO2@Polymer composite particles, the tensile strength, elongation at break and hardness were 2.02 MPa, 129% and 38, respectively. Further increasing the filler amount resulted in decrease of the tensile strength and modulus. In the meantime, although there was a large fraction of polymeric phase in the composite particles, the thermal stability of the resultant particle - silicone rubber composites was not significantly reduced, especially for particle loading exceeding 10 phr. These raspberry-like SiO2@Polymer composite particles are easily produced on a large scale in an environmentally friendly and cost-effective way; thus these are promising novel fillers to reinforce silicone rubber. (c) 2015 Society of Chemical Industry

A series of random copolysiloxanes (PCDMS) containing various amount of γ-cyanopropyl groups are prepared by a new method under mild conditions. Structures of the synthesized polymers are fully characterized by FTIR, 1H NMR, 29Si NMR, and GPC. Rheological properties of PCDMS are tested by cone and plate rheometer, and thermal properties by differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA). Damping properties as well as fuel resistance of the cured PCDMS elastomers are also tested. The correlation between chemical structure, content of cyanopropyl group and properties are discussed. With the increasing amount of polar cyanopropyl group introduced, glass transition temperatures (Tg) of the synthesized PCDMS gradually increases from −121 to −65 °C, residual weight increases from 0 to 36% at 800°C, loss factor reaches as high as 1.74, mass increase under fuel immersion for 14 days can be as low as 3.6%. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1408–1421

In the work reported, we utilized a facile flash nanoprecipitation process to generate Ag nanoparticles@nanospheres polymer composites. Ag nanoparticles can be loaded onto the polymeric polystyrene (PS) nanosphere surface using a simple and inexpensive method through in situ growth; the amount of loaded Ag nanoparticles and the size of holes on the PS surface prepared by flash nanoprecipitation can be fine‐tuned by changing the pH of the water medium and the PS nanoparticles should have a greater specific area. The as‐synthesized Ag@PS composite nanoparticles obtained via the one‐step and continuous preparation route show high catalytic activity in the reduction reaction of 4‐nitrophenol. Importantly, the nanoparticles show no loss of catalytic performance over five cycles.

Patellofemoral pain is a common orthopedic condition in the athletic population. Previous investigators focused on exploring the etiology and investigating the effectiveness of different treatment approaches for patellofemoral pain. However, the severity of symptoms and its corresponding impact on quality of life (QOL) in athletes at different skill levels have not been explored. Such information may help in formulating rehabilitation strategies targeting different levels of athletes.To compare the perception of patellofemoral symptoms and its impact on QOL between professional and amateur athletes with patellofemoral pain.Cross-sectional study.Thirty-eight athletes with patellofemoral pain: 19 professional athletes from the Chinese national track and field team and 19 matched amateur participants recruited from a local track and field club.All participants completed the Chinese version of Kujala scale and Medical Outcomes Study 36-Item Short Form Health Survey (SF-36), which we used to quantify the severity of patellofemoral symptoms and QOL, respectively.Professional athletes demonstrated a significantly higher level of patellofemoral symptoms (P.001) and lower physical functioning subscore of SF-36 (P.014) than did the amateur athletes. We also found a trend of a lower mental health subscore of SF-36 in professional athletes than in the amateurs (P = .07). The Kujala scale score was positively correlated with the subscore of "physical functioning" in both professional athletes (rs = 0.688, P = .001) and amateurs (rs = 0.751, P.001). We also observed a trend of correlation between the subscore in the mental health domain and the severity of patellofemoral symptoms in professional athletes.Athletes at different elite levels might have varied perceptions of patellofemoral pain and the corresponding impact on physical aspects of quality of life. The results of this study may highlight the necessity of addressing psychosocial factors when formulating rehabilitation strategies in the athletic population with patellofemoral pain.

Adiponectin is an important insulin-sensitizing adipokine with multiple beneficial effects on obesity-associated medical complications. It is secreted from adipocytes into circulation as high, medium, and low molecular weight forms (HMW, MMW, and LMW). Each oligomeric form of adiponectin exerts non-overlapping biological functions, with the HMW oligomer possessing the most potent insulin-sensitizing activity. In this study, we reported that emodin, a natural product and active ingredient of various Chinese herbs, activates AMPK in both 3T3-L1 adipocytes and 293T cells. Activation of AMPK by emodin promotes the assembly of HMW adiponectin and increases the ratio of HMW adiponectin to total adiponectin in 3T1-L1 adipocytes. Emodin might activate AMPK by an indirect mechanism similar to berberine. We also found that emodin activates PPARγ and promotes differentiation and adiponectin expression during differentiation of 3T3-L1 preadipocytes. Therefore, emodin is a novel AMPK activator with PPARγ-agonist activity. Our results demonstrate that the effects of emodin on adiponectin expression and multimerization are the ultimate effects resulting from both AMPK activation and PPARγ activation. The dual-activity makes emodin or the derivatives potential drug candidates for the treatment of type 2 diabetes and other obesity-related metabolic diseases.

Annealing is thought to be an effective method to promote chain rearrangement in semicrystalline polymers and improve their physical properties. However, little attention has been paid to the annealing of flow-oriented semicrystalline polymers despite its importance in polymer processing. In this work, the microstructural evolution of injection-moulded polypropylene with an oriented shish-kebab structure upon annealing has been explored with differential scanning calorimetry, small-angle X-ray scattering and scanning electron microscopy, Fourier transform infrared spectroscopy and dynamic mechanical analysis. The results show that annealing gives rise to a chain rearrangement in both the crystalline and amorphous phases. Accompanied by the growth and perfecting of the kebabs, relaxation of the initially oriented chains in the amorphous phase is observed. Then, the relationship between the structure and the resulting mechanical properties is established. (C) 2011 Society of Chemical Industry

A new configuration of an X-band planar microstrip antenna is presented.As the base element a single layer cavity-backed microstrip patch antenna is chosen, and the proposed antenna is optimized by Ansoft HFSS. A metallic cavity is introduced for expanding the frequency band. The simulated and measured results show that the impedance bandwidth with −15 dB return loss is about 24.6%. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2831–2834, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26436

Poly(dimethylsiloxane) (PDMS) composites were prepared by simple blending process using palygorskite (PG) or modified palygorskite (MP). This study has been designed to determine the influences of PG or MP on the thermal stability and the mechanical properties of PDMS composites. The thermal stability of PG and MP were also studied by thermogravimetric analysis (TGA). The results showed that MP had the similar thermal stability to PG, and PG or MP not only increased the thermal stability but also improved the mechanical properties of PDMS composites. Meanwhile, compared with PG/PDMS composites, MP/PDMS composites had better thermal stability and mechanical properties owing to the better dispersion of MP into the matrix, the stronger chemical interfacial interaction between MP and the matrix. Copyright © 2010 John Wiley & Sons, Ltd.