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Symmetry-protected bound states in the continuum (SP-BICs) are one of the most intensively studied BICs. Typically, SP-BICs must be converted into quasi-BICs (QBICs) by breaking the unit cell’s symmetry so that they can be accessed by the external excitation. The symmetry-broken usually results in a varied resonance wavelength of QBICs which are also highly sensitive to the asymmetry parameters. In this work, we demonstrate that QBICs with a stable resonance wavelength can be realized by breaking translational symmetry in an all-dielectric metasurface. The unit cell of metasurface is made of a silicon nanodisk dimer. The Q-factor of QBICs is precisely tuned by changing the interspacing of two nanodisks while their resonance wavelength is quite stable against the interspacing. We also find that such BICs show weak dependence on the shape of the nanodisk. Multiple decompositions indicate that the toroidal dipole dominates this type of QBIC. The resonance wavelengths of QBICs can be tuned only by changing either the lattice constants or the radius of nanodisk. Finally, we present experimental demonstrations on such a QBIC with a stable resonance wavelength. The highest measured Q-factor of QBICs is >3000. Our results may find promising applications in enhancing light–matter interaction.

Background Although a large number of studies have shown that QTc interphase prolongation is common in patients with cirrhosis, there are few studies on the relationship between QTc interphase prolongation and Acute-on-Chronic liver (ACLF) patients in China. In addition, the cause of liver failure that our country causes are different from abroad. This paper attempts to discuss the incidence and potential risk factors of QTc interphase prolongation of HBV-ACLF patients in China. Methods A retrospective analysis was performed on the clinical data of 206 HBV-ACLF patients admitted to our study from January 2016 to December 2021 and 94 healthy controls during the same period. The heart rate (HR) and QT interval of 12-lead electrocardiogram (ECG) of patients after admission were collected, and the corrected QTc interval was calculated by Bazett formula. According to the QTc interval > 440milliseconds, patients were divided into extended group. Results Among 206 HBV-ACLF patients, 68 cases (33%) showed prolonged QTc interval, which was significantly different from 3 cases (3.19%) in the healthy control group (P

Electro-optic modulation based on a graphene nanoelectromechanical system (NEMS) with superlubricity is proposed and systematically theoretical investigated. We demonstrate that the superlubricity greatly improve the performance of photoelectric modulators based on graphene NEMS due to its extremely low coefficient of friction. The modulation voltage of graphene NEMS electro-optic modulation with superlubricity can be reduced to 200 mV, which is 1–3 orders of magnitude larger lower than that of the traditional electro-optical modulator, giving rise to a dramatic reduction of the power consumption of the modulator by approximately 3 orders of magnitude. The modulation response speed can reach nanoseconds, which is 4 orders of magnitude higher than the speed of traditional mechanical electro-optic modulation. At the same time, this modulator has a very wide modulation wavelength range and is not sensitive to the angle of incident light. Two-dimensional material devices, incorporated with mechanical modulation and superlubricity, will have important applications in optoelectronics and optical communication.

Bound states in continuum (BICs) are believed to have the ability to achieve high quality factor (Q factor) resonances, which is very important for plasmonics. However, the study of plasmonic BICs is not sufficient. Herein, we design and fabricate a metal−insulator−metal (MIM) metasurface and demonstrate a one-dimensional plasmonic BIC experimentally. The even-order localized surface plasmon resonance (LSPR) modes have even parity at normal incidence. The symmetry-protected BIC can be achieved at Γ point. The band structure can be tuned by strong coupling between the localized plasmonic resonance and plasmonic lattice mode. Interestingly, two of the hybrid modes are also BICs. Although BICs cannot interact with the far field, we successfully demonstrate BIC splitting through far-field excitation. By further tuning the pitch of the MIM grating, the Friedrich–Wintgen BIC is also observed. Finally, we propose and preliminarily demonstrate an ultrathin bandpass spatial filter. These findings provide a new platform to study optical multipole BICs and can have applications in fields such as nano lasers, ultrasensitive sensors, filters, nonlinearity enhancement, and quantum optics.

A toroidal dipole is a fundamental electromagnetic excitation independent of electric and magnetic dipoles. At present, a great deal of attention has been paid to the characteristics and applications of electric toroidal dipole resonance, while investigation of magnetic toroidal dipole (MTD) resonance is limited. The dielectric metasurface provides a good platform for the excitation of MTD. In this work, we numerically study the MTD response on a silicon tetramer metasurface. The near-field distribution and multipole decomposition fully confirm that the MTD dominates the resonance mode. Also, by integrating the phase-change material G e 2 S b 2 T e 5 film onto this metasurface, the modulation properties of relative transmission, MTD far-field scattering, phase, and local electric and magnetic fields of this hybrid device are effectively studied. The maximum modulation depth of transmission reaches 88%, which is attributed to the strong resonance of MTD. Our work provides a route for the achievement of actively tunable optical nano-devices.

Bile acids (BAs) are classically known to play a vital role in the metabolism of lipids and in absorption. It is now well established that BAs act as signaling molecules, activating different receptors (such as farnesoid X receptor, vitamin D receptor, Takeda G-protein-coupled receptor 5, sphingosine-1-phosphate, muscarinic receptors, and big potassium channels) and participating in the regulation of energy homeostasis and lipid and glucose metabolism. In addition, increased BAs can impair cardiovascular function in liver cirrhosis. Approximately 50% of patients with cirrhosis develop cirrhotic cardiomyopathy. Exposure to high concentrations of hydrophobic BAs has been shown to be related to adverse effects with respect to vascular tension, endothelial function, arrhythmias, coronary atherosclerotic heart disease, and heart failure. The BAs in the serum BA pool have relevant through their hydrophobicity, and the lipophilic BAs are more harmful to the heart. Interestingly, ursodeoxycholic acid is a hydrophilic BA, and it is used as a therapeutic drug to reverse and protect the harmful cardiac effects caused by hydrophobic elevated BAs. In order to elucidate the mechanism of BAs and cardiovascular function, abundant experiments have been conducted in vitro and in vivo. The aim of this review was to explore the mechanism of BAs in the cardiovascular system.

Uterine artery pseudoaneurysm (UAP) is rare but can cause life-threatening postpartum hemorrhage (PPH). To evaluate a novel sandwich embolization technique as a treatment for PPH caused by UAP. This retrospective study included 10 patients with PPH caused by UAP who were treated using a modified sandwich embolization technique at the Radiology Department, Third Affiliated Hospital of Guangzhou Medical University between April 2009 and September 2018. Baseline clinical characteristics, intraoperative data (including treatment effectiveness) and postoperative data (including re-bleeding events and complications) were extracted from the medical records. Uterine arterial angiography showed cystic shadowing of the vascular wall during the arterial phase in all patients. Spraying of contrast agent into the pseudoaneurysm was observed for large UAPs, and the pseudoaneurysm disappeared in the venous phase. The pseudoaneurysm blood supply was from the uterine artery in 9 patients (90%) and the uterine, superior vesical, internal pudendal and nameless little arteries in 1 patient (10%). Bleeding symptoms were completely relieved in all patients after sandwich embolization. Eight patients experienced painful contractions in the perioperative period, but there were no other postoperative complications. During the 1-year postoperative follow-up, 9 patients (90%) had no re-bleeding symptoms/signs. One patient (10%), who had a pseudoaneurysm supplied by the uterine, superior vesical, internal pudendal and nameless little arteries, experienced re-bleeding 20 days after surgery and was treated by hysterectomy. Modified sandwich embolization is an effective treatment for PPH caused by UAP.

Accurate and gridded emission inventories are crucial for better air quality modeling and air pollution policy making. As the economic center of the Shandong province and part of the first batch of open coastal cities in China, Qingdao has been frequently plagued by volatile organic compound (VOC) pollution along with its rapid economic development and urbanization in recent years. In this study, a high spatiotemporal resolution VOC emission inventory for Qingdao was established for the year 2016 using updated source-specific emission factors and the latest activity data for different sources. The anthropogenic sources considered in this study are classified into seven major sources and 46 subcategories. The results indicated that a total of 151.5 kt of VOCs were emitted in Qingdao in 2016. The three largest emission sources, industrial process, on-road mobile, and solvent use sources accounted for 49.9% 20.1%, and 14.1% of the total VOC emissions, respectively. Spatially, the Huangdao District (57.9 kt), the Chengyang District (15.4 kt), and Pingdu City (15.1 kt) were the top three emitters of VOCs. The high concentration of VOCs was mainly distributed in the central areas of Qingdao city and the emissions distribution was highly consistent with its road network. The maximum monthly VOC emissions occurred in June (14.4 kt) and the minimum monthly VOC emissions occurred mainly in February (9.5 kt). The uncertainties in the emission inventory were quantified using a Monte Carlo simulation provided by the Oracle Crystal Ball software. There exist relatively high uncertainties in the on-road mobile (-84.79%, 252.07%), biomass burning (-65.38%, 134.77%) and industrial process (-36.08%, 133.62%) sources. For the complicated species and different reaction rates of ozone formation, the control of the amount of VOCs emitted and the highly reactive VOCs are equally important. Based on the emissions of individual VOC species and the corresponding maximum incremental reactivity (MIR), the ozone formation potential (OFP) profiles of Qingdao City were constructed. The results indicated that alkenes/alkynes and aromatics contributed the most to the OFP and that m/p-xylene, ethylene, propylene, formaldehyde, toluene, trans-2-butene, cis-2-butene, 1-butene, o-xylene, and 1-pentene were the top 10 individual VOC species contributing to the OFP. The contribution of industrial process and on-road mobile sources accounted for 37.5% and 24.5% of the total OFP in Qingdao City, respectively. Both the large VOC emission and OFP indicate that the focus of VOC emission control should be on industrial process and on-road mobile sources in Qingdao City.

Active light manipulation plays a critical role in nanophotonics. In this Letter, we investigate the modulation properties of magnetic dipole (MD) emission based on the phase change material

Hg emission inventory for the coal combustion sector in China during the year 2015 was established according to the most recent emission activity data and emission factors from national official statistics and scientific research. Our results show that Hg emission from coal combustion in China in 2015 reached 264.49 tons, and the emission growth rate during the past 10 years began to slow down due to the extensive use of efficient air pollution control devices and the enhanced proportion of cleaned coal in large power plants. Therein, industry was still the biggest emitter, and the Hg emissions of industry, the thermal power sector, the residential sector and other uses were 154.59, 70.40, 15.67 and 23.83 tons respectively. The five largest Hg-emitting provinces were Shandong, Inner Mongolia, Hebei, Shanxi and Jiangsu, due to their great coal consumption. And five provinces with the biggest per capita Hg emission were Inner Mongolia, Ningxia, Shanxi, Guizhou and Hebei. The monthly variation was analyzed according to the sector characteristic, and results indicate that the industrial sector's emission peak appeared in summer; the thermal power sector had two emission peaks, in January and August; Hg emission from residential and other uses exhibited a weak U shape, and a high-emission-intensity region was mainly concentrated in the east of China year-round.

Clinical development of Hu5c8, a monoclonal antibody against CD40L intended for treatment of autoimmune disorders, was terminated due to unexpected thrombotic complications. These life-threatening side effects were not discovered during preclinical testing due to the lack of predictive models. In the present study, we describe the development of a microengineered system lined by human endothelium perfused with human whole blood, a "Vessel-Chip." The Vessel-Chip allowed us to evaluate key parameters in thrombosis, such as endothelial activation, platelet adhesion, platelet aggregation, fibrin clot formation, and thrombin anti-thrombin complexes in the Chip-effluent in response to Hu5c8 in the presence of soluble CD40L. Importantly, the observed prothrombotic effects were not observed with Hu5c8-IgG2σ designed with an Fc domain that does not bind the FcγRIIa receptor, suggesting that this approach may have a low potential risk for thrombosis. Our results demonstrate the translational potential of Organs-on-Chips, as advanced microengineered systems to better predict human response.

The dosing of anti-Parkinson drugs is considered as the optimal control of the symptoms of PD, and increasing the dose of drugs is a common method to treat the aggravate state of PD. However, this is a case of PD elderly patient who had nephritic syndrome, with an increase in the dose, the symptoms did not get improved，but a series of other adverse effects appeared.

The Yellow River Economic Belt (YREB) plays an important role in China's socio-economic development and ecological security. However, this region has suffered from serious atmospheric pollution in recent years due to intense human activity. Identifying and qualifying the spatio-temporal characteristics of the region's air pollution and its driving forces would help in the formulation of effective mitigation policies. Here, the YREB's spatio-temporal characteristics of air quality were meticulously investigated using air pollution observation, synchronous meteorological, and socio-economic data from 103 cities, for the period of 2014–2019. Furthermore, the factors influencing air pollution were analyzed and qualified. Although air quality improved in the cities of the YREB following the implementation of the Air Pollution Action Plan, the region's quality index (AQI) remained higher than the national average. Annual variations of AQI in the YREB followed a U-shaped pattern, being high in autumn and winter and low in spring and summer; this U shape became shallower following improvements in air quality during autumn and winter. From 2014 to 2019, the annual average AQI values of cities in the eastern, middle, and western YREB dropped from 109.66, 111.70, and 94.65 to 92.00, 103.85, and 73.95, respectively. The air pollution trends of cities revealed obvious spatial agglomeration, and those cities with poor air quality were primarily the western cities of Shandong province, most cities in Henan province, and the eastern cities of Shanxi province. Due to the improvement of air quality in eastern cities, the pollution center of gravity moved gradually from Changzhi (113°3411ʺE, 36°040ʺN) to Linfen (110°5222″E, 36°2344″N). The results of the spatial Durbin model (SDM) indicated that air pollution had an apparent spillover effect in the YREB at the watershed scale, and that government technical expenditure, gross domestic product (GDP) per capita, population density, annual wind speed, and relative humidity all had significant negative overall effects on the AQI values of cities. The green cover rate, ratio of secondary industry, and temperature, meanwhile, all had significant positive total effects. Due to differences the natural conditions and stages of socio-economic development between the eastern, middle, and western cities of the YREB, the impact directions and functional strengths of their key factors differed greatly.

BackgroundThere is lack of clinical evidence supporting the value of the Kyoto classification of gastritis for the diagnosis of Helicobacter pylori (H. pylori) infection in Chinese patients, and there aren’t enough specific features for the endoscopic diagnosis of past infections, which is of special significance for the prevention of early gastric cancer (GC).MethodsThis was a prospective and multicenter study with 650 Chinese patients. The H. pylori status and gastric mucosal features, including 17 characteristics based on the Kyoto classification and two newly-defined features unclear atrophy boundary (UAB) and RAC reappearance in atrophic mucosa (RAC reappearance) were recorded in a blind fashion. The clinical characteristics of the subjects were analyzed, and the diagnostic odds ratio (DOR), sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), area under the receiver operating characteristics curve (ROC/AUC), and 95% confidence intervals were calculated for the different features, individually, and in combination.ResultsFor past infection, the DOR of UAB was 7.69 (95%CI:3.11−19.1), second only to map-like redness (7.78 (95%CI: 3.43−17.7)). RAC reappearance showed the highest ROC/AUC (0.583). In cases in which at least one of these three specific features of past infection was considered positive, the ROC/AUC reached 0.643. For current infection, nodularity showed the highest DOR (11.7 (95%CI: 2.65−51.2)), followed by diffuse redness (10.5 (95%CI: 4.87−22.6)). Mucosal swelling showed the highest ROC/AUC (0.726). Regular arrangement of collecting venules (RAC) was specific for no infection.ConclusionsThis study provides evidence of the clinical accuracy and robustness of the Kyoto classification of gastritis for the diagnosis of H. pylori in Chinese patients, and confirms UAB and RAC reappearance partly supplement it for the diagnosis of past infections, which is of great benefit to the early prevention of GC.

Objective: To estimate the related factors of hysterectomy in patients with Placenta accreta spectrum (PAS) after uterine artery embolization (UAE), and try to evaluate the effectiveness and safety of UAE in patients with PAS.Methods: From January 2012 to July 2020, a retrospective analysis was performed in 85 patients undergoing TAE for PAS. Information regarding clinical data, angiography as well as embolization details, and clinical outcomes was obtained. Univariate and multivariate analyses were performed to determine the factors related to hysterectomy.Results: Bleeding greater than or equal to 500ml during the delivery(p = 0.037), the placenta type by MR or US(placenta increta vs placenta percreta, P = 0.01) and the type of ovarian artery(No vs Bilateral, P = 0.005; Unilateral vs Bilateral, P = 0.01) were independent risk factors of hysterectomy in PAS patients treated with UAE. The area under the curve (AUC) of the predictive model that incorporated the independent risk factors was 0.844. Abnormal collateral vessels communicating with uterine artery were observed on angiography in 24 patients (28.2%) with 31 abnormal collateral vessels. The major abnormal collateral vessel was the abnormal branches of the internal iliac artery(n = 13), followed by the inferior vesical artery (n = 11), internal pudendal artery(n = 3), obturator artery (n = 2), vaginal artery(n = 1) and the abnormal branches of the external iliac artery(n = 1).Conclusions: TAE is safe and effective for patients with PAS. Bleeding greater than or equal to 500ml during the delivery, the placenta type by MR or US and the type of ovarian artery were related to the hysterectomy. For patients with hypertrophic ovarian-uterine artery anastomosis and no fertility requirements, Ovarian artery embolization(OAE) could be a feasible choice.

Background A series of evidence revealed that body mass index was an important confounding factor in the research of uric acid and ischemic heart disease/hypertension. The objective of this study was to investigate whether obesity status can modify the association between serum uric acid and the severity of liver damage in NAFLD, and the possible interactive effect of hyperuricemia and obesity. Methods We conducted a cross-sectional study in a total of 557 ultrasound diagnosed-NAFLD. The hepatic steatosis and liver fibrosis were quantitatively evaluated by transient elastography. Hyperuricemia was defined as serum uric acid > 420 μmol/L in men, > 360 μmol/L in women and obesity was defined as body mass index ≥ 25 kg/m2. The adjusted OR values of hyperuricemia and obesity were analyzed by multivariate logistic regression analysis, and the additive model was used to investigate the possible interactive effect. Results Multivariate regression analysis showed that hyperuricemia was associated with serious hepatic steatosis (1.74[1.09–2.79]) and elevated ALT (2.17[1.38–3.41]), but not with advanced fibrosis (1.61[0.91–2.85]). The association was further investigated in different BMI group. Hyperuricemia was associated with higher odds of serious hepatic steatosis (2.02[1.14–3.57]) and elevated ALT (2.27[1.37–3.76]) only in obese NAFLD, not in non-obese subjects. Similarly, patients with hyperuricemia had higher odds of advanced fibrosis in obese subjects (2.17[1.13–4.18]), not in non-obese subjects (0.60[0.14–2.70]). Furthermore, there was an additive interaction between hyperuricemia and obesity on the odds of serious hepatic steatosis (AP: 0.39[0.01–0.77]) and advanced fibrosis. (AP: 0.60[0.26–0.95]). Conclusions Hyperuricemia and obesity had a significantly synergistic effect on the hepatic steatosis and fibrosis. Thus, management of uric acid may need to be targeted in obese NAFLD.

Shandong is the most populous and highly industrialized province in eastern China, and the resultant poor air quality is a cause for widespread concern. This study combines bottom–up and top–down approaches to develop a high-resolution anthropogenic emission inventory of air pollutants for 2017. The inventory was developed based on updated emission factors and detailed activity data. The emissions of sulfur dioxide (SO2), nitrogen oxides (NOx), particulate matter with aerodynamic diameters smaller than 2.5 and 10 μm (PM2.5 and PM10, respectively), carbon monoxide (CO), volatile organic compounds (VOCs), and ammonia (NH3) were estimated to be 1387.8, 2488.6, 5281.7, 3193.0, 9250.7, 2254.7, and 1210.6 kt, respectively. Power plants were the largest contributors of SO2 and NOx emissions accounting for 43.7% and 41.9% of the total emissions, respectively. CO emissions mainly originated from industrial processes (40.1%), mobile sources (24.8%), and fossil fuel burning (21.2%). The major sources of PM10 and PM2.5 emissions were industrial processes and fugitive dust, contributing 83.0% and 86.9% of their total emissions, respectively. Industrial processes (60.0%) contributed the largest VOC emissions, followed by mobile sources (16.8%) and solvent use (14.5%). Livestock and N-fertilizers were major emitters of NH3, accounting for 69.9% and 21.2% of the total emissions, respectively. Emissions were spatially allocated to grid cells with a resolution of 0.05 ° × 0.05 ° based on spatial surrogates, using Geographic Information System (GIS). Heavy pollutant emissions were mainly concentrated in the central and eastern areas of Shandong, while high NH3–emissions occurred in the western region. Most pollutant emissions from industrial sectors occurred in June and July, while low emissions were recorded between January and February. Range uncertainties in emission inventory were quantified using Monte Carlo simulations. Our inventory provides effective information to understand local pollutant emission characteristics, perform air quality simulations, and formulate pollution control measures.

Lysobacter enzymogenesOH11 is a non-flagellated, ubiquitous soil bacterium with broad-spectrum antifungal activities. Although lacking flagella, it employs another type of motile behavior, known as twitching motility that is powered by type IV pilus (T4P) to move towards neighboring crop fungal pathogens to kill them as food. At present, little is known about how this non-flagellated bacterium controls twitching motility that is crucial for its predatory lifestyle. Herein, we present a report on how a non-canonical PilZ domain, PilZLe3639, controls such motility in the non-flagellatedL. enzymogenes; it failed to bind with c-di-GMP but seemed to be required for twitching motility. Using bacterial two-hybrid and pull-down approaches, we identified PilBLe0708, one of the PilZLe3639-binding proteins that are essential for the bacterial twitching motility, could serve as an ATPase to supply energy for T4P extension. Through site-mutagenesis approaches, we identified one essential residue of PilZLe3639that is required for its binding affinity with PilBLe0708and its regulatory function. Besides, two critical residues within the ATPase catalytic domains of PilBLe0708were detected to be essential for regulating twitching behavior but not involved in binding with PilZLe3639. Overall, we illustrated that the PilZ-PilB complex formation is indispensable for twitching motility in a non-flagellated bacterium.

Kruppel-like factor 10 (KLF10) has been identified as an important regulator in carcinogenesis and cancer progression. However, the role of KLF10 in multiply myeloma (MM) development and progression remains unknown. In present study, we found that KLF10 mRNA and protein were down-regulated in MM tissues and cell lines. Notably, KLF10 inhibited cell proliferation, cell cycle progression and promoted apoptosis in vitro and in vivo. Furthermore, we confirmed that KLF10 inhibited β-catenin nuclear translocation and inhibited PTTG1 transcription. PTTG1 knockdown could mimic the biological effects of KLF10. Moreover, we demonstrated that KLF10 expression was regulated by miR-106b-5p. In MM tissues, miR-106b-5p has an inverse correlation with KLF10 expression. Conclusively, our results demonstrated that KLF10 functions as a tumor suppressor in regulating tumor growth of MM under regulation of miR-106b-5p, supporting its potential therapeutic target for MM.

BACKGROUND Case Based Learning (CBL) is being hottly used in student-centered medical education worldwide. In China, Wechat is the most popular communication app in China and is widely used in all walks of life. We have practiced several years combining Wechat and CBL in the clinical training of oral medicine, promoting outcomes in traditional bedside training. OBJECTIVE This study aimed to demonstrate the acceptability and merits of Wechat CBL in the clinical training of oral medicine. METHODS A total of eighty students and two tutors participated in this study within a 2-month training during Jan. 2018 and Jan. 2020. The control group used bedside mode and the experimental group used bedside plus Wechat CBL mode. The evaluations included participation passion and routine and finial test. The students of clerkship as 10 and residents as 30 in same number respectively between experiment and control groups. RESULTS The participants in the experimental group had a higher degree of participation in the discussion. And the daily assessment and final examination scores of the participants in the experimental group were significantly better than those in the control group (P CONCLUSIONS Wechat CBL mode has a positive effect on students’ learning enthusiasm and knowledge assessments & technology evaluations in clinical training of oral medicine.

SnO2 and CeO2–SnO2 nanocomposites were fabricated using a facile hydrothermal method. The morphology and structure of the prepared SnO2 nanoparticles and CeO2–SnO2 nanosheets were characterized by X-ray diffraction, Raman spectra, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. Furthermore, the gas sensing properties of these nanocomposites were systematically investigated. Gas sensing results suggested that the SnO2 sensing composite with the optimal Ce content of 5 wt% possessed the highest sensor response of 47–750 ppm acetone at the optimum operating temperature of 280 °C. The sensor response improved over 4 times compared to that of the pure SnO2 nanoparticles. Meanwhile, the response time and recovery time of 5 wt% Ce doped SnO2 nanosheets sensor were about 9 s and 5 s, respectively. Moreover, the 5 wt% Ce doped SnO2 nanosheets sensor exhibited a high acetone selectively against methanal, methanol, ethanol and benzene. The enhanced acetone gas sensing performance of CeO2–SnO2 nanosheets can be related to the addition of CeO2 and consequently the modification of morphology and lesser oxidized surface of the nanocomposite. Thus, the facile CeO2–SnO2 nanosheets present significant promise for acetone detection applications.

Active light manipulation plays a critical role in nanophotonics. In this Letter, we investigate the modulation properties of magnetic dipole (MD) emission based on the phase change material G e 2 S b 2 T e 5 hollow nanodisk (GST-HND). The results show that the amorphous GST-HND supports a strong MD response with a radiative decay enhancement of 282 times and quantum efficiency of 100%. More importantly, by tuning the crystallization rate of GST, the active manipulation of MD radiation is achieved with a quantum efficiency modulation depth of up to 95% at a specific wavelength. Our work may provide significant instruction for the active tuning of optical nanodevices.

Lysobacter enzymogenes (L. enzymogenes) is an agriculturally important Gram-negative bacterium that employs T4P (type IV pili)-driven twitching motility to exhibit its antifungal function. Yet, it is still unclear how this bacterium regulates its twitching motility. Here, by using strain OH11 as the working model organism, we showed that a hybrid two-component system ChpA acts as a positive regulator in controlling twitching motility in L. enzymogenes. ChpA is a hybrid TCS (two-component transduction system) contains 7 domains including those for auto-phosphorylation and phosphate group transfer, as well as a phosphate receiver (REC) domain. Mutation of chpA completely abolished the wild-type twitching motility, as evidenced by the absence of mobile cells at the margin of the mutant colonies. Further studies of domain-deletion and phenotypic characterization reveal that domains responsible for phosphorylation and phosphotransfer, but not the REC domain, were indispensable for ChpA in regulating twitching motility. Transcriptome analyses of the chpA knockout strain indicated that ChpA was extensively involved in controlling expression of a wide variety of genes (totaling 243). The products of these differentially expressed genes were involved in multiple physiological and biological functions in L. enzymogenes. Thus, we have not only identified a new regulator controlling twitching motility in L. enzymogenes, but also provided the first report demonstrating the broad impact of the conserved ChpA in gene regulation in Gram-negative bacteria.