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Volatile organic compounds (VOCs) are key components of tropospheric chemistry. We investigated ambient VOCs in an industrial area in Nanjing, China, between July 2018 and May 2020. The sum of the suite of measured total VOC (TVOC) concentrations was 59.8 ± 28.6 ppbv (part per billion by volume) during the investigation period. About twice the TVOC concentrations were observed in the autumn (83 ± 20 ppbv) and winter (77.5 ± 16.8 ppbv) seasons compared to those in spring (39.6 ± 13.1 ppbv) and summer (38.8 ± 10.2 ppbv). In previous studies in Nanjing, oxygenated VOCs (OVOCs) and halocarbons were not measured, and the current TVOC concentration without halocarbons and OVOCs was similar to the previous investigation in the same study area. However, it was twofold higher than the one reported in the nonindustrial suburban area of Nanjing. Due to the industrial influence, the halocarbons VOC group (14.3 ± 7.3 ppbv, 24 %) was the second-largest contributor to the TVOCs after alkanes (21 ± 7 ppbv, 35 %), which is in contrast with the previous studies in Nanjing and also in almost all other regions in China. Relatively high proportions of halocarbons and aromatics were observed in autumn (25.7 % and 19.3 %, respectively) and winter (25.8 % and 17.6 %, respectively) compared to those in summer (20.4 % and 11.8 %, respectively) and spring (20.3 % and 13.6 %, respectively). According to the potential source contribution function (PSCF), short-distance transport from the surrounding industrial areas and cities was the main reason for the high VOC concentrations in the study area. According to positive matrix factorization (PMF) model results, vehicle-related emissions (33 %–48 %) contributed to the major portion of the ambient VOC concentrations. Aromatics, followed by alkenes, were the top contributors to the loss rate of OH radicals (LOH; 37 % and 32 %, respectively). According to the empirical kinetic modelling approach (EKMA) and relative incremental reactivity (RIR) analysis, the study area was in the VOC-sensitive regime for ozone (O3) formation during all measurement seasons. Therefore, alkenes and aromatics emissions from automobiles need to be decreased to reduce secondary air pollution formation in the study area.

Acoustic patterning of micro-particles has many important biomedical applications. However, fabrication of such microdevices is costly and labor-intensive. Among conventional fabrication methods, photolithography provides high resolution but is expensive and time consuming, and not ideal for rapid prototyping and testing for academic applications. In this work, we demonstrate a highly efficient method for rapid prototyping of acoustic patterning devices using laser manufacturing. With this method we can fabricate a newly designed functional acoustic device in 4 hours. The acoustic devices fabricated using this method can achieve sub-wavelength, complex and non-periodic patterning of microparticles and biological objects with a spatial resolution of 60 μm across a large active manipulation area of 10 × 10 mm(2).

Carbonaceous aerosols have great influence on the air quality, human health and climate change. Except for organic carbon (OC) and elemental carbon (EC), brown carbon (BrC) mainly originates from biomass burning as a group of OC, with strong absorption from the visible to near-ultraviolet wavelengths, and makes a considerable contribution to global warming. Large numbers of studies have reported long-term observation of OC and EC concentrations throughout the world, but studies of BrC based on long-term observations are rather limited. In this study, we established a two-wavelength method (658 and 405 nm) applied in the Sunset thermal–optical carbon analyzer. Based on a 1-year observation, we firstly investigated the characteristics, meteorological impact and transport process of OC and EC. Since BrC absorbs light at 405 nm more effectively than 658 nm, we defined the enhanced concentrations (dEC = EC405 nm − EC658 nm) and gave the possibility of providing an indicator of BrC. The receptor model and MODIS fire information were used to identify the presence of BrC aerosols. Our results showed that the carbonaceous aerosol concentrations were the highest in winter and lowest in summer. Traffic emission was an important source of carbonaceous aerosols in Nanjing. Receptor model results showed that strong local emissions were found for OC and EC; however, dEC was significantly affected by regional or long-range transport. The dEC/OC and OC/EC ratios showed similar diurnal patterns, and the dEC/OC increased when the OC/EC ratios increased, indicating strong secondary sources or biomass burning contributions to dEC. A total of two biomass burning events both in summer and winter were analyzed, and the results showed that the dEC concentrations were obviously higher on biomass burning days; however, no similar levels of the OC and EC concentrations were found both in biomass burning days and normal days in summer, suggesting that biomass burning emissions made a great contribution to dEC, and the sources of OC and EC were more complicated. Large number of open fire counts from the northwestern and southwestern areas of the study site were observed in winter and significantly contributed to OC, EC and dEC. In addition, the nearby Yangtze River Delta area was one of the main potential source areas of dEC, suggesting that anthropogenic emissions could also be important sources of dEC. The results proved that dEC can be an indicator of BrC on biomass burning days. Our modified two-wavelength instrument provided more information than the traditional single-wavelength thermal–optical carbon analyzer and gave a new idea about the measurement of BrC; the application of dEC data needs to be further investigated.

Numerous biomarkers of diabetic kidney disease (DKD) are associated with renal prognosis but head-to-head comparisons are lacking. This study aimed to examine the association of soluble tumor necrosis factor receptor type 1 (sTNFR1), fibroblast growth factor 21 (FGF-21), endocan, N-terminal pro-brain natriuretic peptide (NT-pro-BNP), and renal outcomes of patients with or without clinical signs of DKD. A total of 312 patients were enrolled in a prospective observational study that excluded individuals with estimated glomerular filtration rates (eGFR) 30% decline in eGFR and worsening albuminuria or both from consecutive tests of blood/urine during a 3.5-year follow-up period. Higher sTNFR1 and FGF-21, rather than endocan and NT-pro-BNP, levels were associated with renal outcomes but the significance was lost after adjusting for confounders. However, sTNFR1 levels ≥ 9.79 pg/dL or FGF-21 levels ≥ 1.40 pg/dL were associated with renal outcomes after adjusting for the confounders (hazard ration [HR] 2.76, 95% confidence interval [CI] 1.36–5.60, p = 0.005 for sTNFR1 level; HR 1.95, 95% CI 1.03–3.69, p = 0.03 for FGF-21 level). The combination of both levels exhibited even better association with renal outcomes than did either one alone (adjusted HR 4.45, 95% CI 1.86–10.65, p = 0.001). The results were consistent among patients with preserved renal function and normoalbuminuria. Both sTNFR1 and FGF-21 levels were associated with renal outcomes of in patients with type 2 diabetes, and the combination of the abovementioned markers exhibits better predictability.

Mesenchymal stromal cells (MSCs) are multipotent cells that have great potential for regenerative medicine, tissue repair, and immunotherapy. Unfortunately, the outcomes of MSC-based research and therapies can be highly inconsistent and difficult to reproduce, largely due to the inherently significant heterogeneity in MSCs, which has not been well investigated. To quantify cell heterogeneity, a standard approach is to measure marker expression on the protein level via immunochemistry assays. Performing such measurements non-invasively and at scale has remained challenging as conventional methods such as flow cytometry and immunofluorescence microscopy typically require cell fixation and laborious sample preparation. Here, we developed an artificial intelligence (AI)-based method that converts transmitted light microscopy images of MSCs into quantitative measurements of protein expression levels. By training a U-Net+ conditional generative adversarial network (cGAN) model that accurately (mean $$r_s$$ r s = 0.77) predicts expression of 8 MSC-specific markers, we showed that expression of surface markers provides a heterogeneity characterization that is complementary to conventional cell-level morphological analyses. Using this label-free imaging method, we also observed a multi-marker temporal-spatial fluctuation of protein distributions in live MSCs. These demonstrations suggest that our AI-based microscopy can be utilized to perform quantitative, non-invasive, single-cell, and multi-marker characterizations of heterogeneous live MSC culture. Our method provides a foundational step toward the instant integrative assessment of MSC properties, which is critical for high-throughput screening and quality control in cellular therapies.

In the present work, the influence of plastic deformation on the properties of a 3004 Al-alloy was studied with different techniques. Crystallite size, dislocation density, defect density, micro-strain, and stored dislocation energy are presented and compared for different three techniques. Methodology Many techniques for detecting defects have been developed, such as the positron annihilation lifetime technique (PALT), the positron annihilation Doppler broadening technique (PADBT), and the Vickers hardness test (HV). Implications The positron mean lifetime value of a non-deformed sample is 173±4.8 ps, which increases until the thickness reduction reaches a 10% deformation then saturated at saturation trapping of the positron in defect states with a mean of 221±5 ps. At an S-parameter of 0.3709±0.0031, a W-parameter of 0.5885±0.0057 was obtained at zero deformation: this decreases until saturation at 10% deformation. Findings A good correlation between the three techniques is observed for mean crystallite size. A good correlation was also noted between PALT and PADBT from 0 to 10% thickness reduction. HV has good correlations with PALT and PADBT from 0 to 6% thickness reduction: then a clear difference was found from 6 to 15% thickness reduction. Originality such results confirm the fact that the used technique can effects on the obtained results in some limitations.

The concern about gene doping has remained high in horseracing and other equestrian competitions. Our laboratory has previously developed a duplex quantitative polymerase chain reaction (qPCR) assay capable of detecting in equine blood the human erythropoietin (hEPO) transgene and equine tubulin α 4a (TUBA4A) gene as an internal control the latter providing quality control over DNA extraction and qPCR. This study aimed to optimize the method for routine testing of regulatory samples. The use of an automated DNA extraction system has increased the sample throughput, consistency of DNA extraction, and recovery of reference materials. The use of reduced concentration of primers and hydrolysis probe for internal control minimized their competition with transgene amplification and improved the assay sensitivity. Spike-in of an exogenous internal control at low concentration for plasma analysis has also been validated. Using the new workflow, four duplex qPCR assays have been developed for the detection of transgenes, namely, hEPO, human growth hormone (hGH), insulin-like growth factor 1 (hIGF-1), and equine EPO (eEPO). The estimated limits of detection (LODs) of each transgene were 2000 copies/mL of blood and 200 copies/mL of plasma. This method could detect the presence of transgene in blood and plasma collected from a horse administered intramuscularly (IM) with recombinant adeno-associated virus (rAAV) carrying the hEPO transgene. A longer detection time was observed in blood than in plasma. The methods have been applied to the screening of over a thousand official racehorse samples since June 2020 for the presence of these transgenes.

The cortical collecting duct (CCD) of the mammalian kidney plays a major role in the maintenance of total body electrolyte, acid/base, and fluid homeostasis by tubular reabsorption and excretion. The mammalian CCD is heterogeneous, composed of Na+-absorbing principal cells (PCs) and acid-base-transporting intercalated cells (ICs). Perturbations in luminal flow rate alter hydrodynamic forces to which these cells in the cylindrical tubules are exposed. However, most studies of tubular ion transport have been performed in cell monolayers grown on or epithelial sheets affixed to a flat support, since analysis of transepithelial transport in native tubules by in vitro microperfusion requires considerable expertise. Here, we report on the generation and characterization of an in vitro, perfusable three-dimensional kidney CCD model (3D CCD), in which immortalized mouse PC-like mpkCCD cells are seeded within a cylindrical channel embedded within an engineered extracellular matrix and subjected to luminal fluid flow. We find that a tight epithelial barrier composed of differentiated and polarized PCs forms within 1 wk. Immunofluorescence microscopy reveals the apical epithelial Na+channel ENaC and basolateral Na+/K+-ATPase. On cessation of luminal flow, benzamil-inhibitable cell doming is observed within these 3D CCDs consistent with the presence of ENaC-mediated Na+absorption. Our 3D CCD provides a geometrically and microphysiologically relevant platform for studying the development and physiology of renal tubule segments.

Background & Aims Tenofovir disoproxil fumarate (TDF) is the preferred treatment to prevent maternal transmission of HBV, owing to its efficacy and safety. However, data are lacking on the long-term safety outcomes in children following fetal exposure to TDF. Methods Children participating in a prospective, multisite trial of maternal TDF treatment during late pregnancy were recruited for follow-up visits once a year. Growth parameters, serum biochemistry, HBV serology, and bone mineral density (BMD) by dual-energy x-ray absorptiometery scan were measured. Results One hundred and twenty-eight children, 71 in the TDF and 57 in the control group, completed 255 follow-up visits at the age of 2 to 7 (median, 4.08) years. No differences in z-scores for weight-for-age (0.26 ± 0.90 vs. 0.22 ± 0.99, p = 0.481), z-scores for height-for-age (0.20 ± 1.02 vs. 0.25 ± 0.98, p = 0.812), and estimated glomerular filtration rate (169.12 ± 50.48 vs. 169.06 ± 34.46 ml/min/1.73m2, p = 0.479) were detected. After adjustment for age, sex and HBV status by multiple linear regression, children in the TDF and control group had comparable levels of serum calcium, phosphorus, bone-specific alkaline phosphatase, calcidiol and BMD of lumbar spines (0.55 ± 0.01 vs. 0.57 ± 0.01 g/cm2, p = 0.159) and left hip (0.56 ± 0.01 vs. 0.56 ± 0.01 g/cm2, p = 0.926). Conclusions Children of HBV-infected mothers who did or did not receive tenofovir disoproxil fumarate treatment during late pregnancy had comparable long-term growth, renal function, and bone development up to 6–7 years after delivery. Clinical trial number NCT01312012 ( ClinicalTrials.gov ) Lay summary Currently there are insufficient long-term safety data in children born to mothers who took antiviral agents during pregnancy to prevent mother-to-infant transmission of hepatitis B virus (HBV). In this study, we found that children of HBV-infected mothers who did or did not receive tenofovir disoproxil fumarate treatment during late pregnancy had comparable long-term growth, renal function, and bone development up to 6-7 years after delivery.

Particulate nitrate (NO3-) not only influences regional climates but also contributes to the acidification of terrestrial and aquatic ecosystems. In 2016 and 2017, four intensive online measurements of water-soluble ions in PM2.5 were conducted in Nanjing City in order to investigate the potential formation mechanisms of particulate nitrate. During the sampling periods, NO3- was the predominant species, accounting approximately for 35 % of the total water-soluble inorganic ions, followed by SO42- (33 %) and NH4+ (24 %). Significant enhancements of nitrate aerosols in terms of both absolute concentrations and relative abundances suggested that NO3- was a major contributing species to high-PM2.5 events (hourly PM2.5≥150 µg m−3). High NO3- concentrations mainly occurred under NH4+-rich conditions, implying that the formation of nitrate aerosols in Nanjing involved NH3. During the high-PM2.5 events, the nitrogen conversion ratios (Fn) were positively correlated with the aerosol liquid water content (ALWC; R>0.72 and p). Meanwhile, increasing NO3- concentrations regularly coincided with increasing ALWC and decreasing Ox (Ox=O3+NO2). These results suggested that the heterogeneous reaction was probably a major mechanism of nitrate formation during the high-PM2.5 events. Moreover, the average production rate of NO3- by heterogeneous processes was estimated to be 12.6 % h−1 (4.1 µg m−3 h−1), which was much higher than that (2.5 % h−1; 0.8 µg m−3 h−1) of gas-phase reactions. This can also explain the abrupt increases in nitrate concentrations during the high-PM2.5 events. Utilizing the ISORROPIA II model, we found that nitrate aerosol formation in Nanjing during the high-PM2.5 events was HNO3 limited. This indicated that control of NOx emissions will be able to efficiently reduce airborne particulate nitrate concentrations and improve the air quality in this industrial city.

Assessing trends of sea surface wave, wind, and coastal wave setup is of considerable scientific and practical importance in view of recent and projected long-term sea level rise due to global warming. Here we analyze global significant wave height (SWH) and wind data from 1993 to 2015 and a wave model to (i) calculate wave age and explain the causal, or the lack thereof, relationship between wave and wind trends; and (ii) estimate trends of coastal wave setup and its contributions to secular trends of relative sea level at coastal locations around the world. We show in-phase, increasing SWH and wind trends in regions dominated by younger waves, and decreasing SWH trends where older waves dominate and are unrelated to the local wind trends. In the central North Pacific where wave age is transitional, in-phase decreasing wave and wind trends are found over the west-northwestern region, but wave and wind trends are insignificantly correlated in the south-southeastern region; here, a reversed, upward momentum flux from wave to wind is postulated. We show that coastal wave setup depends primarily on open-ocean SWH but only weakly on wind, varying approximately like SWH/(wind speed)1/5. The wave-setup trends are shown to be increasing along many coastlines where the local relative sea level trends are also increasing: the North and Irish Seas, Mediterranean Sea, East and South Asian seas, and eastern United States, exacerbating the potential for increased floods along these populated coastlines.

The TCR is consisted of four chains: α (TCRα), β (TCRβ), γ (TCRγ), and δ (TCRδ) that are present in all jawed vertebrates. Birds are very important in terms of evolutionary aspects of the adaptive immune system, in which it bridges the evolutionary gap between mammals and other vertebrates. To gain better understanding into the genomic organization and complexity of birds’ TCR loci, we applied cross-reference error-correction sequencing approach by using Illumina and single-molecule real-time sequencing technology to resequence genomic regions of chicken TCR loci based on 10 mapped bacterial artificial chromosome clones. We did de novo classification of V and J genes for all four chains of the TCR loci according to our sequencing results using the Immunogenetics nomenclature. In sum, we identified 85, 8, and 37 TCR V gene segments in the chicken TCRα/TCRδ, TCRβ, and TCRγ loci, respectively. The phylogenetic analysis showed the Vα 7 and Vα family 4 gene sequences shared greater sequence similarity with mammalian species, whereas the other Vα segment sequences are evolutionary closer with sequences from bony fishes. The organization of chicken TCRβ locus is more similar to fish TCRβ locus over mammalian species, as chicken TCRβ locus has a single translocon of its V–D–J–C and exhibits significantly fewer Vβ gene segments. In this study, we present a highly precise genomic map for chicken TCR loci and phylogenetic relationships of TCR variable gene segments against other animal species and verified the relative stability of the receptor structure during evolutional process.

A coating/contact dual-layer structure is fabricated via co-sintering in simulated interconnect/coating/contact/cathode test cells. Two different precursors are utilized to form Mn1.25Co1.75O4 and Ce-doped Mn1.25Co1.75O4 spinel coatings, while a mixture of Mn oxide and Co metal powders is employed as the contact material. After thermal conversion into a dense coating and a porous contact layer at 900 °C in air simultaneously, both test cells exhibit excellent electrical performance during the 1500-h area-specific resistance (ASR) measurement at 800 °C, due to the unique dual-layer structure via co-sintering. The cell with Ce-containing coating precursor shows better cell ASR behavior and lower degradation rate. Cross-sectional observation of the tested cells is conducted to assess the compatibility of the dual-layer structure with adjacent components as well as its effectiveness in inhibiting chromia scale growth and blocking Cr migration from the interconnect to the cathode.

The plastic forming of titanium alloy tubes at room temperature exhibits strong anisotropy, low elongation, and large deformation resistance. Numerical control warm bending assisted forming technology can improve the stability of the titanium alloy tube bending process, increase the bending limit and reduce the springback angle. This technology promotes the wide application of high-precision titanium alloy bent tubes in many high-end fields such as aerospace, shipbuilding, chemical industry, and military industry. However, the titanium alloy tube bending at high temperatures involves complex material rheological behavior and microstructure characteristics. The coupling relationship between the stress-strain properties of the material and the temperature field makes it difficult to predict the springback behavior of titanium alloy tubes after warm bending. In this paper, based on the mechanical behavior of titanium alloy tubes at high temperatures, a constitutive model of titanium alloy suitable for local heating is improved. The theoretical model of springback for warm rotary draw bending of titanium alloy tube is established. The influence of warm bending strategies on the springback of bending is studied. The theoretical model is verified by establishing a thermal-mechanical coupling finite element model for the whole process of warm bending under the state of heat balance. The results show that the bending springback theory based on the modified John-Cook model can accurately simulate the temperature change of titanium alloy tube section, adapt to local heating strategies and provide high prediction accuracy of bending springback.

Our calculation shows that negative refractive index (NRI), which was known to exist only in metamaterials in the past, can be found in Dirac semimetals (DSM). Electrons in DSM have zero effective mass and hence the system carries no nominal energy scale. Therefore, unlike those of ordinary materials, the electromagnetic responses of the electrons in DSM will not be overwhelmed by the physical effects related to electron mass. NRI is induced by the combination of the quantum effect of vacuum polarization and its finite temperature correction which is proportional to $T^4$ at low temperature. It is a phenomenon of resonance between the incident light and the unique structure of Dirac cones, which allows numerous states to participate in electron-hole pair production excited by the incident light with similar dispersion relation to that of Dirac cones. NRI phenomenon of DSM manifests in an extensive range of photon frequency and wave number and can be observed around giga Hertz range at temperature slightly higher than room temperature., Accepted by Physical Review Letters ( https://journals.aps.org/prl/accepted/47073Yc9P1b18c84c34f8d016596af92c6645e364 )