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The amount of cosmic dust contributed by stellar sources in galaxies at all cosmic epochs remains a controversial topic, particularly whether or not supernovae (SNe) have an important role to play given the dust-hostile environments provided by SNe. To date, freshly-formed dust has been observed in a handful of core collapse (CC) SNe, both in the ejecta in-situ and in the interactions between the ejecta and circumstellar medium (CSM). As yet, there exists no clear observational evidence for dust formation in Type Ia SNe despite predictions of $3×10^{-4}$- $0.2$ Msun of dust forming per Ia. Here we report evidence of dust formation in the ejecta-CSM interaction in the Type Ia (SNIa) SN2018evt just three years after the explosion, characterized by a staggering rise in the mid-infrared (MIR) flux accompanied by an accelerated decline in the optical. This hypothesis is strengthened by the concurrent evolution of the profiles of the Hα emission lines. A preexisting hydrogen-rich torus which itself may be dusty before the SN explosion, provides a natural explanation of the observed data. SN 2018evt is the first SNIa with clear evidence of both dust destruction and formation in its ejecta and surroundings. The amount of the newly formed dust follows a steep power law rise of index 4 with time after the explosion. This steep rise indicates that the newly formed dust is formed in the SN ejecta, which is compressed by the shock interaction with the CSM.

We have obtained optical spectroscopy and photometry data during four years after the event. The long-term photometric light-curve and the equivalent widths of the Halpha and He I 6678 lines were used to monitor the state of the Be star disk. The Halpha line profiles show evidence for V/R variability that was accounted for by fitting the Halpha spectral line profile with two Gaussian functions. We divided our data into three phases according to the intensity of the X-ray, optical, and infrared emission. Phase I covers the rise and decay of the giant X-ray outburst that took place in October to November 2017. We interpret phase II as the dissipation of the Be star equatorial disk and phase III as its recovery. The timescale of a complete formation and dissipation process is about 1250 days. The epoch when the dissipation process stopped and the reformation period began is estimated to be around MJD 58530. We find a delay of about 100 to 200 days between the minimum of the optical or infrared intensity and the strength of the Halpha line after the X-ray outburst, which may indicate that the dissipation of the disk begins from the inner parts. The motion of the density perturbation inside the disk is prograde, with a V/R quasi-period of about four years. The source shows a positive correlation in the (B-V) color index versus V-band magnitude diagram, which implies that the system is seen at a small or moderate inclination angle., 15 pages, 5 figures

Epidemiological studies have reported an association between traffic-related pollution with risk of metabolic syndrome (MetS). However, evidence from prospective studies on the association of walkability and nitrogen dioxide (NOA total of 17,965 participants without MetS diagnosed within one year at baseline were included in our study from a population-based prospective cohort in Yinzhou District, Ningbo, Zhejiang Province, China. Participants were followed up by the regional Health Information System (HIS) until December 15, 2021. MetS was defined based on the criteria of Chinese Diabetes Society (CDS2004). We used walkscore tools, calculating with amenity categories and decay functions, and spatial-temporal land-use regression (LUR) models to estimate walkability and NOOverall, we followed up 77,303 person-years and identified 4040 incident cases of MetS in the entire cohort. Higher walkability was inversely associated with incident MetS (HR = 0.94, 95 % CI: 0.91-0.99), whereas NOIn summary, we found living in areas with lower walkability and higher concentrations of NO

As far as we know, the CO2 photoconversion reaction with H2O includes two important steps. One step is CO2 photoreduction (photogenerated electrons) while the other step is the oxidation of water (photogenerated holes). It is obvious that the oxidation of water is also the key step in the CO2 photoconversion reaction. However, little research has been done to improve the oxidation of water, thereby indirectly improving the photocatalytic CO2 reduction property of TiO2. Moreover, CO2 adsorption capacity is also considered as an important limiting factor for the CO2 photoconversion activity. Therefore, in this paper, CoPi (an amorphous cobalt-phosphate-based material) with high CO2 adsorption capacity was successfully immobilized on the surface of TiO2 nanosheets and served as a hole-cocatalyst to trap holes, thereby delaying the recombination of photogenerated electrons and holes and providing more CO2 gas to take part in the CO2 reduction reaction. Hence, the TiO2/CoPi exhibited much better CO2 photoconversion performance in water compared to pristine TiO2.

Exposure to residential greenness might affect population health through increasing physical activity and social engagement, improving mental health, and reducing harmful environmental exposure. However, evidence on the association of greenness with risk of diabetes is still controversial. In this study, we recruited a total of 22,535 participants aged ≥18 years from Yinzhou District, Ningbo, Zhejiang Province, China to investigate the associations between residential greenness and risk of diabetes incidence. Residential greenness was estimated using Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI), and Vegetation Continuous Field (VCF). We also calculated cumulative average NDVI, EVI and VCF values, and changes in NDVI, EVI and VCF during the follow-up period. We used Cox proportional hazards models controlling for demographic characteristics, lifestyles, individual socioeconomic status, history of diseases and particulate matter with an aerodynamic diameter ≤2.5 μm (PM

Walkability has been considered to be associated with metabolic and cardiovascular diseases, but the relationship between walkability and chronic obstructive pulmonary disease (COPD) remains unclear. Moreover, fine particulate matter (PMWe used prospective data of 29,572 participants from the Yinzhou cohort in Ningbo, China. COPD cases were diagnosed based on the Yinzhou Health Information System (YHIS). Walkability was measured using walk score in relation to the built environment based on geographic information systems (GIS). Air pollution levels were assessed by fitting land use regression (LUR) models. Cox proportional hazards models were used to evaluate the relationships of PMOverall, a total of 29,572 participants were included in the final analysis and 722 COPD incident cases were identified during 134,846 person-years of follow-up. Compared with subjects with lower walkability, individuals with higher walkability had a decreased risk of COPD (HR = 0.88, 95 % CI: 0.82-0.95) for every IQR increase. By contrast, exposure to PMLiving in a highly walkable neighborhood could decrease risk of COPD, whereas high levels of PM

Red blood cell (RBC) transfusion is a clinically effective therapy in anemia, for example in patients with malignancies (Shander et al., 2020), bleeding (Odutayo et al., 2017), and preoperative anemia (Padmanabhan et al., 2019). The past few decades have witnessed a shortage of blood for transfusion due to limited health insurance coverage for blood use and the rapid expansion of hospitals (Chen et al., 2011; Shi et al., 2014). Blood donation levels may easily be affected by general changes in the environment, policy, major events such as disasters, and public sentiment (Hu et al., 2019). Meanwhile, the transfusion of allogeneic RBC is a double-edged sword, increasing the possibility of infectious and immunological complications, and also leading to higher morbidity and mortality after transfusion (Frank et al., 2012). Considering that the continual shortfall has been increasingly prominent, identifying the factors associated with RBC transfusion could help blood transfusion departments to improve their supply of blood products as well as their inventory management (O'Donnell et al., 2018).

CdS and ZnS quantum dots were obtained via a modified gel crystal growth method using hydrogel (HR) as a kind of gel and a special substrate, which effectively suppressed the agglomeration of CdS and ZnS nanoparticles in the growth process via using chemical adsorption effect and utilizing the feature of gel crystal growth method (the sites of nuclei, growth and minimizing precipitation for the crystals were restricted spatially in the gel). The structural, growth mechanism and photocatalytic H2 evolution properties of these MS(M = Cd, Zn)/HR were investigated. The MS/HR composites exhibited high rates of H2 evolution compared to those of bulk MS, benefited to the synergistic effect of quantum dots and HR. The quantum dots extend the band gap and provide abundant catalytically-active sites and HR was used as a miniature hydrogen production reactor due to the large volumes of water in its swollen structure derived from its super H2O adsorption capacity, which efficiently avoided the agglomeration of MS quantum dots during the photocatalytic hydrogen evolution process. This work may provide an excellent approach for the preparation of quantum dots and miniature hydrogen production reactor shows a potential application in water splitting.

Black liquor, an industrial waste product of papermaking, is primarily used as a low-grade combustible energy source. Despite its high lignin content, the potential utility of black liquor as a feedstock in products manufacturing, remains to be exploited. Demonstrated here in is the use of black liquor as a primary feed-stock for synthesizing graphene quantum dots that exhibit both up-conversion and photoluminescence when excited using visible/near-infrared radiation, thereby enabling the photosensitization of ultraviolet-absorbing TiO2 nanosheets. In addition, these graphene quantum dots can trap photo-generated electrons to realize the effective separation of electron-hole pairs. Together, these two processes facilitate the solar-powered generation of H2 from H2 O, and CO from H2 O-CO2 , using broadband solar radiation.

We report experimental studies on the optical properties of an exciton polariton condensate confined in an optically defined trap at room temperature. As a result of the parabolic profile of the optical trap, the polariton condensate redistributes itself in simple harmonic oscillator states, forming an analog of the gravity pendulum. We observed the coexistence of two harmonic oscillator modes in a single trap, which were confirmed to be confined modes connected by longitudinal optical (LO) phonons using Raman spectroscopy. Clear features of mode competition behaviors were observed for these two harmonic oscillators when the injection rate of polaritons was varied. The observed mode competition was successfully simulated by a three-level rate equation model. In addition, as a result of the bosonic stimulation in the trap region, up to ∼88% of the injected polaritons were successfully trapped when polariton lasing takes place.

The coronavirus disease (COVID-19) has become a global public health threaten. A series of strict prevention and control measures were implemented in China, contributing to the improvement of air quality. In this study, we described the trend of air pollutant concentrations and the incidence of COVID-19 during the epidemic and applied generalized additive models (GAMs) to assess the association between short-term exposure to air pollution and daily confirmed cases of COVID-19 in 235 Chinese cities. Disease progression based on both onset and report dates as well as control measures as potential confounding were considered in the analyses. We found that stringent prevention and control measures intending to mitigate the spread of COVID-19, contributed to a significant decline in the concentrations of air pollutants except ozone (O3). Significant positive associations of short-term exposure to air pollutants, including particulate matter with diameters ≤2.5μm (PM2.5), particulate matter with diameters ≤10μm (PM10), and nitrogen dioxide (NO2) with daily new confirmed cases were observed during the epidemic. Per interquartile range (IQR) increase in PM2.5 (lag0-15), PM10 (lag0-15), and NO2 (lag0-20) were associated with a 7% [95% confidence interval (CI): (4 - 9)], 6% [95% CI: (3 - 8)], and 19% [95% CI: (13 - 24)] increase in the counts of daily onset cases, respectively. Our results suggest that there is a statistically significant association between ambient air pollution and the spread of COVID-19. Thus, the quarantine measures can not only cut off the transmission of virus, but also retard the spread by improving ambient air quality, which might provide implications for the prevention and control of COVID-19., Graphical abstract Image 1, Highlights • There is a statistically significant association between ambient air pollution and the spread of COVID-19. • The lag days from onset date to report date of COVID-19 were taken into account. • The quarantine measures can not only cut off the transmission of virus, but also retard the spread by improving ambient air quality., Short-term exposure to air pollutants, including PM2.5, PM10, NO2, may contribute to an increase in the counts of daily onset cases. Stringent prevention and control measures can not only cut off the transmission of virus, but also retard the virus spread by reducing air pollution, which might provide implications for the prevention and control of COVID-19.

Growing evidence has linked residential greenness to depression, the results from prospective cohort study are still limited. And it remains unclear whether particulate matter (PM) modify, mediate, or interact the greenness-depression relationship.We collected data from Yinzhou Cohort(N = 47,516) which was recruited between June 2015 and December 2017. Depression cases before April 2020 were ascertained from local Health Information System covered all residents' health care records. Residential greenness (the Normalized Difference Vegetation Index, NDVI, and the Enhanced Vegetation Index, EVI) and PM (particulate matters with diameters≤2.5 μm, PMDuring the 99,556 person-years of follow-up, 1043 incident depression cases occurred. In single exposure models, residential greenness was inversely associated with depression incidence (e.g. Hazard Ratio (HR) = 0.86, 95% confidence interval (CI): 0.79, 0.94 for per interquartile range (IQR) increase NDVI 250 m). The protective association between greenness was attenuated after introducing PMIn this longitudinal cohort study, residents living in greener neighborhoods had a lower risk of depression incidence and the benefits were interacted and partly mediated by PM. Improvement in residential greenness could be an actionable and planning intervention to prevent depression.

Background Long-term exposure to ambient air pollution was linked to depression incidence, although the results were limited and inconsistent. Objectives To investigate the effects of long-term air pollution exposure on depression risk prospectively in China. Methods The present study used data from Yinzhou Cohort on adults without depression at baseline, and followed up until April 2020. Two-year moving average concentrations of particulate matter with a diameter ≤ 2.5 μm (PM2.5), ≤10 μm (PM10) and nitrogen dioxide (NO2) were measured using land-use regression (LUR) models for each participant. Depression cases were ascertained using the Health Information System (HIS) of the local health administration by linking the unique identifiers. We conducted Cox regression models with time-varying exposures to estimate the hazard ratios (HRs) and 95% confidence intervals (95% CIs) of depression with each pollutant, after adjusting for a sequence of individual covariates as demographic characteristics, lifestyles, and comorbidity. Besides, physical activity, baseline potential depressive symptoms, cancer status, COVID-19 pandemic, different outcome definitions and air pollution exposure windows were considered in sensitivity analyses. Results Among the 30,712 adults with a mean age of 62.22 ± 11.25, 1024 incident depression cases were identified over totaling 98,619 person-years of observation. Interquartile range increments of the air pollutants were associated with increased risks of depression, and the corresponding HRs were 1.59 (95%CI: 1.46, 1.72) for PM2.5, 1.49 (95%CI: 1.35, 1.64) for PM10 and 1.58 (95%CI: 1.42, 1.77) for NO2. Subgroup analyses suggested that participants without taking any protective measures towards air pollution were more susceptible. The results remained robust in all sensitivity analyses. Conclusions Long-term exposure to ambient air pollution was identified as a risk factor for depression onset. Strategies to reduce air pollution are necessary to decrease the disease burden of depression.

Improving CO2 adsorption capacity, suppressing the recombination of carriers, and extending the light absorption range are key challenges for obtaining high efficiency photocatalytic conversion of CO2 with H2O as reducing agent. In this paper, we proposed using noble metal Ag and activated carbon obtained from biomass with high CO2 adsorption capacity to modify TiO2, thus assembling a TiO2/AC-Ag ternary composite photocatalyst via using ultrasonic and situ photodeposition methods. The TiO2/AC-Ag displayed six times increase in CO yield compared to that of pristine TiO2. The enhanced CO2 photoconversion performance can be attributed to the following three factors: (1) The activated carbon not only leads to enhanced CO2 adsorption capacity due to its properties and high surface area but also makes the electron transfer to its surface due to similar conductivity to metals derived from diverse electronic structures of activated carbon, thereby suppressing the recombination of photo-generated electron and hole pairs. (2) The oxidation reaction sites of H2O are located on the surface of TiO2 and the reduction reaction sites of CO2 are on the surface of activated carbon; the effective separation of two reaction sites remarkably inhibited the reverse reaction during CO generation. (3) The surface plasmon resonance (SPR) of Ag enables the materials to absorb light in a broader spectrum.

Discontinuous modulation of the modular multilevel converter can be used for reduction of submodule capacitor voltages and switching losses by clamping one of the arms to its corresponding dc-rail. In this paper, the impact of discontinuous modulation in the losses as well as the expected thermal performance of the devices in the submodules of the converter are evaluated by a direct comparison with a normal modulation strategy. Three loss estimation methods are also reviewed in order to identify the impact that the choice of a loss calculation method might have in the loss value as well as the temperature estimations of the converter. The extended simulation results provided demonstrate loss reduction in the MMC as a result of discontinuous modulation together with variations in maximum temperatures across the devices of a submodule.

Background Though growing evidence has linked air pollution to Parkinson's disease (PD), the results remain inconsistent. Less is known about the relevance of road proximity and surrounding green. We aimed to investigate the individual and joint associations of air pollution, road proximity and surrounding green with the incidence of PD in a prospective cohort study. Methods We used data from a prospective cohort of 47,516 participants recruited from July 2015 to January 2018 in Ningbo, China. Long-term exposure to particulate matter with aerodynamic diameter ≤2.5 μm (PM2.5) and ≤10 μm (PM10) and nitrogen dioxide (NO2) estimated by land-use regression models, road proximity and surrounding green assessed by Normalized Difference Vegetation Index (NDVI) were calculated based on the residential address for each participant. Cox proportional hazard models were used to analyze the individual and joint effects of air pollution, road proximity, and surrounding green on PD. Results In single-exposure models, PM2.5, PM10, NO2 and road proximity was associated with increased risk of PD (e.g. Hazard Ratio (HR) = 1.51, 95%CI:1.02, 2.24 per interquartile range (IQR) increase for PM2.5) while surrounding green was associated with decreased risk of PD (e.g. HR = 0.80, 95%CI:0.65, 0.98 per IQR increase for NDVI in 300 m buffer). In two-exposure models, the associations of PM2.5 and surrounding green persisted while the associations of NO2 and road proximity attenuated towards unity. Conclusions We found that PM2.5 were associated with increased risk of incident PD while surrounding green was associated with decreased risk of PD. Future studies about PD etiology may benefit from including multiple environmental exposures to address potential joint associations.

A carbon-based solid acid catalyst (CHACS) derived corncob residual was prepared by incomplete hydrothermal carbonization followed by activation with phosphoric acid impregnation and sulfuric acid sulfonation. The structure of the solid acid catalyst was characterized using Fourier transform infrared spectra (FTIR), thermogravimetric analyzer (TGA), X-ray diffraction (XRD), scanning electron microscope (SEM), specific surface area (SSA), and elemental analysis. The -SO3H, -COOH, and phenolic -OH functional groups were successfully introduced. Phosphoric acid activation facilitated formation of the porous structure in the solid acid catalyst. The specific surface area and acid density were 1569 m2/g and 1.030 mmol/g, respectively. The CHACS exhibited better catalytic activity for hydrolysis conversion of corn stalk in ionic liquid with water as solvent. A total reducing sugars (TRS) yield of 68.3% was obtained in water and a TRS yield of 52.5% was obtained in an ionic liquid of [BMIM][Cl] at 140 °C for 120 min. The CHACS expressed good catalytic activity in each of 4 separate instances of reuse.

Background The association between Alu methylation and risk of cancer remains uncertain. This meta-analysis was conducted to elucidate this issue. Materials and Methods PubMed and Web of Science up to December 31, 2018, and the reference lists of studies, as well as those presented in relevant meta-analyses and reviews were systematically searched. Standardized mean difference (SMD) in Alu methylation level between cases and controls were pooled using random effects model and assessed heterogeneity between strata by stratified factors using meta-regression model. Sensitivity analysis and publication bias test were also conducted. Results Twenty-five articles, including 2719 cases and 3018 controls were included in the meta-analysis. The significant difference in Alu methylation level between cancer cases and controls was greater in tissue (SMD = −1.89, 95% CI: −2.72, −1.05) than blood (SMD = −0.46, 95% CI: −0.82, −0.09), and heterogeneity was found in materials (P = 0.038). In tissue samples, Alu hypomethylation was found in carcinoma (SMD = −2.50, 95% CI: −3.51, −1.48), while not in non-carcinoma. The inverse associations were consistently found in subgroups stratified by data sources and quality score in tissue samples, and publication year was considered to be the potential source of between-study heterogeneity. Moreover, reduced Alu methylation level was found in the European subgroup, detection method of SIRPH and COBRA, and original data source in blood samples. Conclusions Alu hypomethylation was associated with increased risk of cancer, which could be a potential biomarker for cancer.

Exciton-polaritons, formed by the strong coupling between excitons and cavity-confined photons, are the building blocks of polaritonic devices. In this work, we report experimental realization of an all-optically controlled dynamic superlattice for polaritons working in the ultraviolet wavelength range at room temperature. The optical superlattice was realized on a one-dimensional (1D) ZnO microrod using an array of periodically arranged laser spots. Polaritonic mini-band features were clearly observed by both momentum- and real-space imaging spectroscopy. By controlling the periodicity of the laser spots, we demonstrated that the band structures of polaritons can be well controlled by external lasers. Theoretically, by extending the Kronig-Penney model to the polariton system, we calculated the polaritonic mini-bands and found it to be in good agreement with our experimental observations. By imaging the polariton flow in real space, the lifetime of polaritons and their relationship with their exitonic fractions were also extracted. The polaritonic superlattices demonstrated in this work are fully reconfigurable and optically controlled, and our results could thus stimulate the development of polaritonic all-optical devices.

We report experimental observation of strong coupling between surface plasmon polariton (SPP) propagating on a thin silver film and excitons from excited-subband transtitions of single-walled carbon nanotubes (SWNTs). Clear anti-crossing behaviors were observed from attenuated total reflection measurements when the SPP energy approaches the 2nd subband transition of (6,5) SWNTs. The maximum Rabi splitting of the plasmon-exciton mixed states was extracted to be up to ~166.2 meV. Moreover, the splitting was found to be dependent linearly on the square root of the SWNTs concentration, in good agreement with theoretical prediction.

Summary Background and objective Indoxyl sulphate (IS) and p-cresyl sulphate (PCS), which are difficult to excrete adequately out of the body, are closely related to the progression of chronic kidney disease (CKD) and various deuteropathy. Better than peritoneal dialysis (PD) and haemodialysis (HD), dietary fibre has been considered to reduce IS and PCS levels. In view of the absence of formal recommendations on fibre intake in CKD nutritional guidelines, we conducted this meta-analysis to assess the effects of dietary fibre on IS and PCS for CKD patients. Methods The effects were pooled and expressed in terms of weighted mean difference (WMD) with 95% confidence interval (95% CI). Q test and I2 statistics were used to assess the heterogeneity. Results A total of 12 relevant estimates from 7 reports, including 203 CKD patients, showed that dietary fibre significantly reduced their PCS level (WMD = −16.160, 95% CI: −23.824, −8.495). Conclusions The meta-analysis produced a strong corroboration that dietary fibre intake does have a good therapeutic effect on patients with CKD. The conclusions need to be validated by randomised controlled experiments (RCT) with better design, larger samples, longer course of treatment and higher quality.

The application of confinement potential is an efficient way to improve the optical properties of exciton polaritons. In this work, we report experimental studies on the effects of potential landscapes on confined polariton states. The spatial confinement of polaritons was realized by imposing two optically-controlled barriers on a one-dimensional ZnO microrod. Two types of quantized polariton states were observed, where energies of the levels depend either linearly or quadratically on their quantum number. The formation of optical traps with parabolic or square-well profiles was confirmed to be responsible for the observed different states. These results demonstrate the importance of the potential landscapes in tailoring the optical properties of exciton polaritons, which would be helpful in the design of polariton-based optoelectronic devices.

When all the parts of the wavefront imaging system are kept static after wavefront measuring, the target's images are blurry, because the depth of field (DOF) of the system affects the imaging quality. In this paper, the method for extending the DOF of the wavefront imaging system through an integrated architecture of a liquid-crystal microlens array (LCMLA) powered by electricity and a common photosensitive array, is presented. The DOF can be extended remarkably only by stitching together several sub-images of the LCMLA. The problem that the wavefronts and imaging results are insensitive to the objective depth is also solved. Optimal driving voltage signals are found out according to Sobel mean gradient to efficiently calibrate the depth of objective space in order to quantitatively measure the depth. The approach indicates a viable way to effectively extend the DOF of imaging micro-systems and to measure the geometrical depth of targets at the same time.

We report experimental studies on the Fabry-Perot (F-P) type polariton modes and their dynamics using a modified Young's double-slit interference technique. The technique was based on the angle-resolved micro-photoluminescence spectroscopy and optimized for nanostructure measurements. Using this technique, we directly revealed the parity of the F-P type polariton modes from the angle-dependent interference spectra. Moreover, clear features of mode competition were observed from the power dependence of the interference patterns. The observed competition behaviors can be well simulated by a five-level rate equation model.

Single-walled carbon nanotubes suffer severely from their extremely low luminescence quantum yield and spectral purity. In this work, we produced brightly and directionally luminescent, as well as spectrally pure, carbon nanotubes by embedding them into a wedge-shaped planar cavity. By controlling the detuning between the cavity mode and exciton emission, the photoluminescence of carbon nanotubes could be enhanced up to 60 times. Coupling efficiency, i.e., percentage of nanotube luminescence emitted into a cavity mode, was found to be detuning dependent with a maximum efficiency of ∼54%. Moreover, emission from nanotubes inside the cavity becomes highly directional. The emission angle was measured to be less than 1.8 °, demonstrating their great potential in device applications of future optoelectronics.