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Protonic ceramic electrolysis cells (PCECs) have attracted significant attention as a promising technology for green hydrogen production and conversion. However, traditional PCECs oxygen electrodes exhibit poor electrochemical performance because of their limited hydration ability and lack of intrinsic protonic conductivity. In this study, a W-doped perovskite oxide, Sr 2 Fe 1.5 Mo 0.4 W 0.1 O 6-δ (SFMW), with a strong hydration capacity and an accelerated proton mobility, was designed to serve as the oxygen electrode in PCECs. The results indicate that W doping enhances the concentration of oxygen vacancies in Sr 2 Fe 1.5 Mo 0.5 O 6-δ (SFM) and facilitates the adsorption of H 2 O onto the oxygen electrode, thereby significantly accelerating proton mobility. The bulk diffusion coefficient of protons (D H) in SFMW, estimated through electrical conductivity relaxation measurement, can reach up to 2.86 × 10−5 cm∙s−1 at 750 °C, which is significantly higher than that of SFM (7.96 × 10−6 cm∙s−1). Consequently, SFMW exhibited impressive electrochemical performance, as evidenced by its lower polarization resistance (0.072 Ω⋅cm2, 700 °C in air) and higher current density (945 mA/cm2 with a voltage of 1.3 V at 650 °C) in PCECs. These results suggest that accelerating bulk proton transfer by W doping is highly feasible and holds great potential for the development of oxygen electrodes for high-activity PCECs. [ABSTRACT FROM AUTHOR]

Ferroptosis-based nanoplatforms have shown great potential in cancer therapy. However, they also face issues such as degradation and metabolism. Carrier-free nanoplatforms consisting of active drugs can effectively avoid the security issues associated with additional carrier ingredients. Herein, a biomimetic carrier-free nanoplatform (HESN@CM) was designed to treat cancer by modulating cascade metabolic pathways of ferroptosis. CCR2-overexpressing macrophage membrane-modified HESN can target cancer cells via the CCR2-CCL2 axis. The acidic tumor microenvironment (TME) can disrupt the supramolecular interaction of HESN, releasing hemin and erastin. Then, erastin could induce cancer cells ferroptosis by inhibiting system X C − pathways, while hemin, a vital component of blood to transport oxygen, could be broken down by heme oxygenase-1 (HO-1), increasing the intracellular Fe2+ concentration to induce cancer cells' ferroptosis further. Meanwhile, erastin could enhance the activity of HO-1, further promoting the release of Fe2+ from hemin. As a result, HESN@CM demonstrated superior therapeutic efficacy in both primary and metastatic tumors in vitro and in vivo. The carrier-free HESN@CM provided cascade ferroptosis tumor therapy strategies for potential clinical application. CCR2-overexpressing biomimetic carrier-free nanoplatform (HESN@CM) was designed for cancer treatment by modulating metabolic pathways of ferroptosis. HESN modified with CCR2-overexpressing macrophage membrane can target tumor cells via the CCR2-CCL2 axis. HESN was composed of hemin and erastin without additional vectors. Erastin could directly induce ferroptosis, while hemin could be broken down by heme oxygenase-1 (HO-1), increasing the intracellular Fe2+ concentration to enhance ferroptosis further. Meanwhile, erastin could improve the activity of HO-1, promoting the release of Fe2+ from hemin. Therefore, HESN@CM with good bioavailability, stability, and simple preparation can realize cascade ferroptosis tumor therapy and have the potential prospect of clinical translation. [Display omitted] [ABSTRACT FROM AUTHOR]

Due to the influence of time, load, and external environmental factors, many reinforced concrete beams have been damaged and require repair. Tailings are waste generated during mineral production, resulting in substantial environmental pollution and economic losses due to the excessive generation of tailings and low comprehensive utilization. In the UHDC, tailings replaced quartz sand, while BFRP grids itself is an environmentally friendly material. Two repair methods were evaluated in this study, Tailings Sand Ultra-High Ductile Concrete (TSUHDC) and Basalt Fiber Reinforced Polymer (BFRP) grid-TSUHDC, grounded in the principles of green and sustainable development. Five reinforced concrete beam specimens were designed and fabricated for bending performance tests and finite element simulations. The effects of different repair methods and levels of damage on the flexural performance of reinforced concrete beams were investigated. The results reveal that, compared to untreated reinforced concrete beams, both TSUHDC and BFRP grid-TSUHDC repair methods enhanced bending load-bearing capacity. However, the stiffness of specimens repaired with TSUHDC decreased when subjected to 80 % of the pre-applied failure load. When the pre-applied failure load is less than 80 %, the recommended repair approach is the use of TSUHDC for repair. For cases where the pre-applied failure load exceeds 80 %, BFRP grid-TSUHDC is the preferable option. The flexural bearing capacity formula for this type of repair method was derived by improving existing formulas, yielding prediction results in close alignment with the experimental results. • TSUHDC and BFRP grid-TSUHDC repair methods were evaluated in this study. • The effects of different repair methods and levels of damage on the flexural performance of RC beams were investigated. • TSUHDC is suitable for repairing minor damage structures. For major damage, the preferred option is BFRP grid-TSUHDC. [ABSTRACT FROM AUTHOR]

Graphene-like boron nitride (h -BN) has the large surface area. The h -BN/CdS composite was successfully synthesized by one-step hydrothermal method. In this work, the physical structure, morphology, optic and electronic property of the h -BN/CdS photocatalyst were characterized and explored via XRD, SEM, TEM, XPS, UV–vis DRS, EIS and transient photocurrent. The heterojunction between h -BN and CdS could enhance the efficiency of charge transfer and significantly suppress the recombination of electrons and holes. The photocatalytic performance of the h -BN/CdS composite was evaluated by degrading rhodamine B (RhB) and photocatalytic reducing Cr (Ⅵ) ion, respectively. Moreover, 1.0 wt% h -BN/CdS composite could effectively inhibit the agglomeration of CdS nanospheres, which displayed the optimum photocatalytic activity under visible light irradiation. Meanwhile, 1.0 wt% h -BN/CdS composite had outstanding feature in recycling stability. The results indicated that two-dimensional (2D) h -BN as a substrate of CdS nanospheres was beneficial to prolong photoexcited electrons lifetime. The heterostructure interfaces of the h -BN/CdS composites resulted in photocatalytic performance promotion. However, the excessive h-BN caused the serious aggregation of CdS nanospheres. This work showed a facile method for the rational design of photocatalyst via optimizing their structure and surface. [ABSTRACT FROM AUTHOR]

Abstract Self-piercing riveted (SPR) connections are gradually being used in cold-formed steel structures due to higher tensile strength, shear strength and connection efficiency compared to those of self- drilling connections. With the purpose of investigating the flexural behavior of truss beams with SPR connections and studying the effects of height and span, as well as diagonal web arrangement, on their flexural stiffness and ultimate bearing capacity, the symmetric vertical static load test was conducted for 5 cold-formed thin-walled truss beam specimens with SPR connections. The finite element software was adopted to simulate the test models, and the more parameters were additionally analyzed. The research indicated that the failure modes of the specimens can be divided into two types: the local strength failure mode occurred when the upper chord flange plate was cracked, the other one occurred when the rivets at joints of truss beams were stripped from the plate. The span-height ratio, spacing of web members, chord thickness and number of rivets had great influence on the flexural stiffness and ultimate bearing capacity of truss beams with SPR connections, while the thickness of web members and the arrangement of diagonal web members had less influence. The truss beam was a simply supported beam with a weak web. A theoretical formula was proposed to calculate the equivalent flexural stiffness of the truss beam with SPR connections based on parametric analysis, and it agreed with the experiment results, so the proposed theoretical formula is valid and can be applied to practical engineering. Highlights • Pilot research on self-piercing rivet connections in cold-formed steel truss beams. • The failure mechanism and failure modes of truss beams using self-piercing rivets are analyzed. • The influence of various factors on the flexural behavior of truss beams with SPRs is investigated and design suggestions are developed. • A theoretical formula calculated the equivalent flexural stiffness of truss beam based on test results and parametric analysis is proposed. [ABSTRACT FROM AUTHOR]

Abstract The earth has abundant water resources, and efficient harvesting of energy from waves is always a research hotspot. In this paper, we fabricate a box-like triboelectric-electromagnetic hybrid nanogenerator for harvesting water wave energy, which is composed of the triboelectric nanogenerator (TENG) and the electromagnetic generator (EMG). In the case of TENG, the contact and separation between the aluminum film-coated PMMA cylinder and the silicone film covered interdigitated Ag electrodes is formed by ocean waves. In the case of EMG, a rolling magnetic ball is placed on the four coils to generate magnetic flux changes, thus generating electricity. Several experiments are conducted to validate the availability. Experimental results show that the instantaneous maximum output power of TENG is 0.08 mW at a load of 100 MΩ, and the instantaneous maximum output power of EMG is 14.9 mW at a load of 1 kΩ. The hybrid nanogenerator can light up 60 LEDs at the same time. After storing energy in the capacitor, the output DC signal can provide a continuous energy supply with the temperature sensor. More important, the nanogenerator can power the wireless acoustic sensing system. Graphical abstract fx1 Highlights • Combined with TENG and EMG, it can harvest more energy at wider frequencies. • A new rolling structure to harvest two-dimensional direction random wave energy. • It has potential applications in self-powered wireless acoustic sensing system. [ABSTRACT FROM AUTHOR]

Atmospheric PM 2.5 poses a variety of health and environmental risks to urban environments. Ammonium is one of the main components of PM 2.5 , and its role in PM 2.5 pollution will likely increase in the coming years as NH 3 emissions are still unregulated and rising in many cities worldwide. However, partitioning urban NH 4 + sources remains challenging. Although the 15N natural abundance (δ15N) analysis is a promising approach for this purpose, it has seldom been applied across multiple cities within a given region. This limits our understanding of the regional patterns and controls of NH 4 + sources in urban environments. Here, we collected PM 2.5 samples using an active sampling technique during winter at six cities in the North China Plain to characterize the concentrations, δ15N and sources of NH 4 + in PM 2.5. We found substantial variations in both the concentrations and δ15N of NH 4 + among the sites. The mean NH 4 + concentrations across the six cities ranged from 3.6 to 12.1 μg m−3 on polluted days and from 0.9 to 10.6 μg m−3 on non-polluted days. The δ15N ranged from 6.5‰ to 13.9‰ on polluted days and from 8.7‰ to 13.5‰ on non-polluted days. The δ15N decreased with increasing NH 4 + concentrations at all six sites. We found that non-agricultural sources (vehicle exhaust, ammonia slip and urban wastes) contributed 72%–94% and 56%–86% of the NH 4 + on polluted and non-polluted days, respectively, and that during polluted days, combustion-related emissions (vehicle exhaust and ammonia slip) were positively associated with the proportion of urban area, population density and number of vehicles, highlighting the importance of local sources of particulate pollution. This study suggests that the analysis of 15N in aerosol NH 4 + is a promising approach for apportioning atmospheric NH 3 sources over a large region, and this approach has potential for mapping rapidly and precisely the sources of NH 3 emissions. [Display omitted] • Non-agricultural and agricultural sources contributed 82% and 18% to NH 4 + in PM 2.5. • Aerosol NH 4 + on polluted winter days in six cities was mainly of local origin. • Combustion-derived NH 4 + positively related to urban area size and vehicle numbers. • Agricultural contribution to NH 4 + increased with increasing agricultural coverage. [ABSTRACT FROM AUTHOR]

Radiotherapy is a compatible regimen for synergizing immune checkpoint blockade therapy by promoting immunogenic cell death. To improve the efficiency of irradiation-induced neoantigen generation, we designed and developed an ozone-carrying liposome perfluorodecalin (PFD) nano-system (O 3 _PFD@Liposome) which promoted ozone solubility by 18.4-fold compared to that in water solution. The O 3 _PFD@Liposome particle remarkably improved the irradiation-induced hydroxyl radical generation. Evaluation of sub-cellular biodistribution indicated that the nano-system could be efficiently internalized by tumor cells. Upon released inside tumor cells, ozone generated reactive oxygen species under the stimulation of X-ray irradiation. Notably, O 3 _PFD@Liposome significantly prompted anti-tumor efficacy of radiotherapy without inducing severe adverse effects. The combo regimen with radiotherapy and ozone potently enhanced the infiltration of lymphocytes in the tumor microenvironment by inducing immunogenic cell death, releasing neoantigens, and relieving hypoxia symptom. Consequently, the combination of ozone-fueled irradiation and PD-1 blockade synergistically inhibited the growth of primary and abscopal tumors. [Display omitted] • Ozone may serve as an efficient donor of ROS and oxygen under the agitation of irradiation. • Ozone-loaded perfluorodecalin liposome sensitizes radiotherapy by enhancing ROS productivity and attenuating hypoxia. • Combination of O 3 _PFD@Liposome and irradiation promotes tumor-infiltrating lymphocyte by augmenting immunogenic cell death. • On top of ozone-fueled irradiation, PD-1 blockade further enhances growth inhibition of primary and abscopal tumors. [ABSTRACT FROM AUTHOR]

Therapeutic strategies based on an enhanced hepatitis B virus (HBV)-specific cytotoxic T lymphocyte (CTL) activity may eradicate HBV. We previously verified that a fusion protein ubiquitin (Ub)-hepatitis B core antigen (HBcAg)-cytoplasmic transduction peptide (CTP) can enter the cytoplasm of dendritic cells and enhance T cell response to generate HBV-specific CTLs efficiently in vitro . Ub, a marker of protein degradation, may promote the generation of peptides appropriate for major histocompatibility complex class I presentation. In the present study, the specific immune responses of the fusion protein Ub-HBcAg-CTP in BALB/c mice were evaluated and the underlying mechanisms were investigated. Results showed that Ub-HBcAg-CTP increased the anti-HBcAg titer and produced the cytokines IFN-γ and IL-2. This fusion protein also induced higher percentages of IFN-γ + CD8 + cells and specific CTL responses. Ub-HBcAg-CTP could also upregulate the expressions of Jak2, Tyk2, STAT1, and STAT4 in T lymphocytes. In conclusion, Ub-HBcAg-CTP enhanced cellular and humoral immune responses and induced robust HBV-specific CTL activities in BALB/c mice. [ABSTRACT FROM AUTHOR]

Effects of human activities on atmospheric nitrate (NO 3 -) formation remain unclear, though the knowledge is critical for improving atmospheric chemistry models and nitrogen deposition reduction strategies. A potentially useful way to explore this is to compare NO 3 - oxidation processes in urban and rural atmospheres based upon the oxygen stable isotope composition of NO 3 - (Δ17O–NO 3 -). Here we compared the Δ17O–NO 3 - from three-years of daily-based bulk deposition in urban (Shenyang) and forested rural sites (Qingyuan) in northeast China and quantified the relative contributions of different formation pathways based on the SIAR model. Our results showed that the Δ17O in Qiangyuan (26.2 ± 3.3‰) is significantly higher (p < 0.001) than in Shenyang (24.0 ± 4.0‰), and significantly higher in winter (Shenyang: 26.1 ± 6.7‰, Qingyuan: 29.6 ± 2.5‰) than in summer (Shenyang: 22.7 ± 2.9‰, Qingyuan: 23.8 ± 2.4‰) in both sites. The lower values in the urban site are linked with conditions that favored a higher relative contribution of nitrogen dioxide reaction with OH pathway (0.76-0.91) than in rural site (0.47-0.62), which should be induced by different levels of human activities in the two sites. The seasonal variations of Δ17O–NO 3 - in both sites are explained by a higher relative contribution of ozone-mediated oxidation chemistry and unfavorable conditions for the OH pathway during winter relative to summer, which is affected by human activities and seasonal meteorological condition change. Based on Δ17O, wintertime conditions led to a contribution of O 3 related pathways (NO 3 + DMS/HC and N 2 O 5 hydrolysis) of 0.63 in Qingyuan and 0.42 in Shenyang, while summertime conditions led to 0.15 in Qingyuan and 0.05 in Shenyang. Our comparative study on Δ17O–NO 3 - between urban and rural sites reveals different anthropogenic effects on nitrate formation processes on spatial and temporal scales, illustrating different responses of reactive nitrogen chemistry to changes in human activities. [Display omitted] • Δ17O of bulk deposited NO 3 − was lower in urban versus rural atmosphere. • Δ17O–NO 3 - was lower in summer and higher in winter in both urban and rural sites. • Urban nitrate yielded lower Δ17O than the rural site due to chemistry differences. • Lower Δ17O values are due to higher contributions of the OH formation pathway. [ABSTRACT FROM AUTHOR]

Abstract: Fiber-shaped solar cells (FSCs) have attracted increasing interest in recent years due to their numerous advantages. Herein we report the first prototype of highly flexible all-solid-state single-wire FSCs by using CuInSe2 (CIS) as the model photoactive semiconductor. CIS layer is electrodeposited on a flexible Mo wire as the substrate. Subsequently, CdS, ZnO and ITO layers are orderly deposited on the Mo/CIS wire, and each upper layer ensures full contact with the underlying layer, resulting in an excellent structural uniformity along circumference of the FSC. This Mo/CIS/CdS/ZnO/ITO single-wire FSC exhibits a power conversion efficiency of 2.31%, which is one of the highest values in all reported FSCs. More importantly, the present all-solid-state single-wire FSC exhibits stable conversion efficiency (2.16–2.32%) during rotation (0∼360°), bending (0∼360°) and long-time aging (stored at 60°C for 600h) processes, which makes it possible to fabricate very long single-wire FSC with stable efficiency for weaving large-area devices and/or the stereoscopic cell textiles. Our method provides a new and general approach for fabricating flexible single-wire FSC with various kinds of photovoltaic semiconductor materials, and it also would be applicable to develop other flexible electronic circuits. [Copyright &y& Elsevier]

Vehicular exhaust has been identified as an important ammonia (NH 3) emission source in urban areas using the stable isotope tracer technique (δ15N); however, its δ15N signature remains poorly constrained due to difficulties in concentrating and speciating NH x (NH 3 + particulate NH 4 +). In this study, we deployed two active sampling techniques, MCIs (Multi-nozzle Cascade Impactor sampler; "particle-gas" order) and CCSCs (ChemComb Speciation Cartridge sampler; "gas-particle" order), to collect vehicular exhaust NH x in a long urban tunnel in Shenyang, China, and quantified the 15N from the collected NH 3 and NH 4 +. While no significant difference in tunnel NH 3 concentrations between the two samplers was observed (n = 21), the δ15N-NH 3 was slightly higher using the MCIs (6.3 ± 1.6‰) compared to the CCSCs (4.8 ± 2.3‰) during the tunnel operation period. This minor absolute difference of 1.5 ± 2.8‰ may derive from denuder-saturation used within the CCSCs that lead to NH x speciation ambiguity, which also caused significant δ15N-pNH 4 + differences between the two sampling approaches. Our results suggest that both active samplers can well characterize the δ15N-NH x in the ambient environment, but the "particle - gas" sampling approach performs better in elevated NH 3 concentration environments. We recommend that the δ15N value of 6.3‰ is used as the isotope end member for vehicle NH 3 when performing NH 3 source apportionment. [Display omitted] • Two types of active samplers were used to collect vehicular exhaust NH x in urban tunnel. • Minor δ15N–NH 3 difference (~1.5‰) was observed between two types of active samplers. • The "particle - gas" sampling type may perform better in high NH 3 environments. • A value of 6.3‰ is recommended as the δ15N signatures of vehicle NH 3 for source apportionment. [ABSTRACT FROM AUTHOR]

Study Objective: Our hypothesis was that a pre-operative posteromedial quadratus lumborum (QL) block would reduce postoperative morphine consumption and provide superior analgesia in the setting of multimodal analgesia compared with a lateral transversus abdominis plane (TAP) block for laparoscopic colorectal surgery.Design: A randomized controlled study.Setting: A single tertiary hospital. March to August 2018.Patients: 80 ASA I-II colorectal cancer patients undergoing laparoscopic radical resection were enrolled. 77 patients (group QL 38, group TAP 39) were included in the analysis.Intervention: Pre-operatively, patients were randomized to receive either a QL or TAP block (0.375% ropivacaine 20 ml bilaterally for each group).Measurements: The primary outcome was cumulative morphine consumption 24 h postoperatively. Secondary outcomes included postoperative pain scores, clinical recovery, and side-effect profiles of the blocks.Main Results: For the primary outcome measure, morphine consumption 24 h postoperatively was significantly lower in the QL group than in the TAP group (estimated median difference -8 mg, adjusted 95% confidential interval -12 to -6 mg, P < 0.001). The pain visual analogue scores at rest and during movement were found to be statistically significantly lower in the QL group than in the TAP group 8, 12, and 24 h postoperatively (P < 0.006). The QL group reported higher overall satisfaction scores regarding postoperative analgesia than the TAP group (P = 0.014). One patient in the QL group experienced moderate back pain close to the needle entry site postoperatively. There was no statistically significant difference in postoperative nausea and vomiting, bowel recovery or length of hospital stay between the groups.Conclusions: The pre-operative bilateral, ultrasound-guided posteromedial QL block reduces morphine consumption and improves analgesia in the setting of multimodal analgesia compared with the lateral TAP block after laparoscopic colorectal surgery. [ABSTRACT FROM AUTHOR]

Introduction: Shock has been established as a disorder of the microcirculation. Despite various treatments, the mortality rate of infectious shocks remains 30–50%. The study was designed to explore the effects of scopolamine on the survival time, microcirculation and inflammatory cytokine secretion in rats with septic shock. Methods: SD rats were randomly divided into seven groups: a sham group, a control group, a saline group and four scopolamine group. The rat septic shock model was induced by cecal ligation, perforation and drainage, while the operation in the sham group involved opening and closing the abdominal cavity. The survival time was recorded to determine a suitable dose for the subsequent experiments. The microcirculation of the terminal ileum was observed. The concentrations of IL-10, IL-6 and TNF-α in the plasma and lungs were detected by ELISA, and the wet-dry ratio of the lung was calculated. Results: Compared to the control and saline group, the septic shock rats treated in the scopolamine group had a longer survival time, a lower reduction in arteriolar blood flow, and a decreased change in the average diameter of arterioles and venules. The rat wet–dry lung ratio was less in the sham, control and scopolamine groups compared to the saline group. The plasma and lung cytokine concentrations of the rats belonging to the scopolamine group were less than those of the control and saline groups; however, all of the cytokine concentrations were higher than those of the sham group. Conclusions: Scopolamine reduced the plasma and lung concentrations of specific cytokines, improved the function of the microcirculation and prolonged the survival time of rats with septic shock. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Predominant T helper cell type 1 (Th1) immune responses accompanied by boosted HBV-specific cytotoxic T lymphocyte (CTL) activity are essential for the clearance of hepatitis B virus (HBV) in chronic hepatitis B (CHB) patients. Ubiquitin (Ub) serves as a signal for the target protein to be recognized and degraded through the ubiquitin-proteasome system (UPS). Ubiquitinated hepatitis B core antigen (Ub-HBcAg) has been proved to be efficiently degraded into the peptides, which can be presented by major histocompatibility complex (MHC) class I resulting in stimulating cell-mediated responses. In the present study, lentiviral vectors encoding Ub-HBcAg (LV-Ub-HBcAg) were designed and constructed as a therapeutic vaccine for immunotherapy. HBcAg-specific cellular immune responses and anti-viral effects induced by LV-Ub-HBcAg were evaluated in HBV transgenic mice. We demonstrated that immunization with LV-Ub-HBcAg promoted the secretion of cytokines interleukin-2 (IL-2), interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α), generated remarkably high percentages of IFN-γ-secreting CD8 + T cells and CD4 + T cells, and enhanced HBcAg-specific CTL activity in HBV transgenic mice. More importantly, vaccination with LV-Ub-HBcAg could efficiently decreased the levels of serum hepatitis B surface antigen (HBsAg), HBV DNA and the expression of HBsAg and HBcAg in liver tissues of HBV transgenic mice. In addition, LV-Ub-HBcAg could upregulate the expression of T cell-specific T-box transcription factor (T-bet) and downregulate the expression of GATA-binding protein 3 (GATA-3) in spleen T lymphocytes. The therapeutic vaccine LV-Ub-HBcAg could break immune tolerance, and induce potent HBcAg specific cellular immune responses and therapeutic effects in HBV transgenic mice. [ABSTRACT FROM AUTHOR]

Identifying the sources of increased ammonia (NH 3) in the atmosphere has important implications for air quality, ecosystems, and climate. While analysis of the nitrogen isotopic composition (δ15N) can aid in the apportionment of NH 3 emission sources, the widely-used passive collection methods have not been verified for their ability to accurately characterize δ15N-NH 3. In this study, three types of passive samplers (ALPHA, Analyst, and Radiello) were employed and collocated with a denuder based active sampler (DELTA, serves as a reference method) to compare and contrast their ability in collecting atmospheric NH 3 for subsequent concentration and δ15N-NH 3 analysis in urban Beijing during the summer of 2018. The results showed that NH 3 concentrations determined using passive collection samplers that included ALPHA (n = 11), Analyst (n = 12), and Radiello (n = 7) samplers were 13.4%, 14.4%, and 27.5% lower than that of the active sampler (n = 12), respectively. The low NH 3 concentration bias in the passive collection samplers was suggested to be the result of inaccurate effective sampling rates due to incorrect mass transfer correction factors for the environmental conditions of this study. The δ15N-NH 3 values did not show significant differences between passive samplers, with weekly means of −31.0 ± 1.0‰ (n = 4), −28.4 ± 5.5‰ (n = 4), and −29.1 ± 0.9‰ (n = 4) for the ALPHA, Analyst, and Radiello, respectively. Notably, the overall mean δ15N-NH 3 values collected by these passive samplers (−29.5 ± 3.2‰, n = 12) was significantly lower than that of the active sampler (−14.1 ± 1.6‰, n = 4), with a difference of 15.4 ± 3.5‰. The large underestimation of δ15N-NH 3 values by passive samplers can be explained by the diffusive isotope fractionation of NH 3 isotopologues, which is driven by relative mass differences of 14NH 3 and 15NH 3. Overall, these findings highlight a potential low bias in NH 3 concentrations and a substantial uncertainty in previous source interpretation using δ15N-NH 3 as previous studies have almost exclusively characterized δ15N-NH 3 using passive samplers. We suggest that the denuder-based active sampler should be used in the future for characterizing δ15N-NH 3 whether at the source or in an atmospheric environment with mixed sources. This work also has important implications for characterizing δ15N of other gaseous nitrogen compounds. Unlabelled Image • Nitrogen isotopic composition of ammonia (δ15N-NH 3) aids in source apportionment. • Conventional collection methods for δ15N-NH 3 were almost based on passive samplers. • δ15N-NH 3 obtained by passive and active samplers were respective −29.5‰ and −14.1‰. • The low bias of 15.4‰ by passive δ15N-NH 3 was due to diffusive isotope fractionation. • Source apportionment based on passive δ15N-NH 3 might mislead mitigation strategy. [ABSTRACT FROM AUTHOR]

Nanomaterials employed for enhanced drug delivery and therapeutic effects have been extensively investigated in the past decade. The outcome of current anticancer treatments based on conventional nanoparticles is suboptimal, due to the lack of biocompatibility, the deficient tumor targeting, the limited drug accumulation in the diseased region, etc. Alternatively, DNA-based nanocarriers have emerged as a novel and versatile platform to integrate the advantages of nanotechnologies and biological sciences, which shows great promise in addressing the key issues for biomedical studies. Rather than a genetic information carrier, DNA molecules can work as building blocks to fabricate programmable and bio-functional nanostructures based on Watson Crick base-pairing rules. The DNA-based materials have demonstrated unique properties, such as uniform sizes and shapes, pre-designable and programmable nanostructures, site-specific surface functionality and excellent biocompatibility. These intrigue features allow DNA nanostructures to carry functional moieties to realize precise tumor recognition, customized therapeutic functions and stimuli-responsive drug release, making them highly attractive in many aspects of cancer treatment. In this review, we focus on the recent progress in DNA-based self-assembled materials for the biomedical applications, such as molecular imaging, drug delivery for in vitro or in vivo cancer treatments. We introduce the general strategies and essential requirements for fabricating DNA-based nanocarriers. We summarize the advances of DNA-based nanocarriers according to their functionalities and structural properties for cancer diagnosis and therapy. Finally, we discuss the challenges and future perspectives regarding the detailed in vivo parameters of DNA materials and the design of intelligent DNA nanomedicine for individualized cancer therapy. Over the past decade, DNA nanocarriers have emerged as a novel and versatile platform to integrate the advantages of nanotechnologies and biological sciences. Based on Watson Crick base-pairing rules, DNA molecules can work as building blocks to fabricate programmable and bio-functional nanostructures. As a promising candidate for nanocarrier, self-assembled DNA architecture holds distinct advantages, e.g., inherent biocompatibility, precisely designed nanoscale shapes and sizes, tailored functionality, and responsive reconfiguration. These intrigue features allow DNA nanostructures to carry functional moieties to realize precise tumor recognition, customized therapeutic functions and stimuli-responsive drug release, making them highly attractive in many aspects of cancer treatment. Unlabelled Image [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A strategy is proposed to improve the performance of triboelectric nanogenerators. • The maximum continuous power can be boosted dramatically by electrostatic discharge. • This design reduces the optimal impedance that is important for circuit matching. • With this design triboelectric nanogenerators can directly drive low-power devices. • This work is also significant for macro-energy conversion, such as ocean energy. Abstract There is plenty of exploitable energy in the ambient environments. Triboelectric nanogenerator is an innovative electricity generation technology to convert the wasted mechanical energy into electrical energy. However, the output of conventional triboelectric nanogenerators cannot be employed efficiently because their tremendous internal resistance limits the current of electrons. Inspired by the principle of lightning rods, for the first time we propose the utilization of electrostatic discharge to improve the performance of triboelectric nanogenerators, which is realized by an opposite needles structure enclosed in an inert atmosphere. When this structure is connected in series with a vertical contact-separation triboelectric nanogenerator, the strong electric field near tips of two needles ionizes the gas around them, forming a conductive plasma channel between the tips, and releasing a mass of free charges. As a result, some exciting performances are obtained in triboelectric nanogenerator. The output peak-to-peak voltage is increased from 300 V to 1300 V, and the equivalent impedance of energy harvesting circuit is reduced from 100 MΩ to 10 kΩ. Especially in the optimal conditions, the maximum continuous power can even be significantly improved by 330.76%. Therefore, this work provides a new strategy for the energy conversion technology, which is significant for the advancement and application of triboelectric nanogenerators. [ABSTRACT FROM AUTHOR]

In order to introduce self-piercing rivet (SPR) technique to component connections of thin-walled steel structures, 78 SPR joints were tested to evaluate their quality and the shear strength. Parameters included in this test program were the sheet thickness, and the rivet. Based on test results, the research developed an empirical formula between the combination thicknesses of sheet and rivet length, and proposed quality evaluation standard of SPR connections and a new design method of shear strength. The test results showed that sheet thickness and sheet thickness ratio had a great effect on failure mode, and rivet length was a key factor on shear properties of SPR connections. The proposed quality evolution standard and design calculation method of shear strength in this paper had certain reasonability and reliability. [ABSTRACT FROM AUTHOR]

With the purpose of introducing a new connection to cold-formed steel structure, this paper presents an experimental investigation of cold-formed steel (CFS) shear walls with self-piercing riveted (SPR) connections under monotonic and reversed cyclic loading. The effects of loading type (Monotonic and Cyclic), rivet spacing at the steel sheet edges, rivet number at CFS framing joints, axial compression ratio, and the steel sheathing types (steel sheet sheathing and corrugated steel sheathing) on mechanical behavior and failure modes of CFS shear walls were investigated. The shear strength, initial stiffness, and ductility of CFS shear walls with SPR connections were evaluated by comparing to the results of CFS shear walls with self-drilling screw connections under the same condition. Lateral loading, safety factor, and resistance factor under the wind and seismic loads were determined in accordance with test results of CFS shear wall with SPR connections. The research indicated that the rivet spacing at the sheet edges was a key factor affecting failure modes and mechanical properties of CFS shear walls. The relationship of shear strength and ultimate deformation decreased linearly with the increase of the rivet spacing. Compared to CFS shear walls with self-drilling screw, CFS shear walls with SPR have significantly improved shear strength and stiffness. Safety factor and resistance factor recommended by AISI Seismic Design Standard are conservative for the wind and seismic design of CFS shear wall using SPR connections. [ABSTRACT FROM AUTHOR]

The paper presents an experimental investigation on the tensile behavior and strength of self-piercing rivet (SPR) connections used in cold-formed thin-walled steel structures. The sheet thickness ratio, the sheet combination type, and the rivet length were analyzed for their effects on the tensile performance of SPR connections. The research also studied the feasibility of the existing calculation method of SPR connections and the other design methods of self-tapping screw connections for the SPRs investigated herein. Based on the test results and analyses, a new design method for the tensile capacity was proposed. The test results showed that the sheet thickness ratio, the sheet combination type, and the rivet length were the key factors controlling the failure mode and the tensile capacity of SPR connections. The proposed design method for the tensile capacity of SPR connections considers those primary factors as well as the different failure modes. [ABSTRACT FROM AUTHOR]

The paper presents an experimental investigation on the shear strength of self-piercing rivet connections used in thin-walled steel structures. The test program included specimen variations in the number of rivets in each connection, rivet spacing, end distance, and steel sheet thickness. According to the experimental results, the curve of load-slip, peak load, and failure mechanism for all specimens were analyzed. Parameters of riveting in terms of end distance, spacing, arrangement, length, and thickness difference between connection components were studied on their effects for shearing performances of self-piercing rivet connections. A design method based on the model of transmission dynamics of infectious diseases was proposed for calculating the shear strength of the rivet connections. The strength reduction due to the effect of group rivets was considered in the new method. [ABSTRACT FROM AUTHOR]

The goal of this study was to verify the ultrasound features of hyper-echoic rims in thyroid nodules and to evaluate their diagnostic value in predicting thyroid malignancies. We retrospectively analyzed 228 pathologically proven thyroid nodules (137 malignant and 91 benign nodules). Forty-eight thyroid nodules had a hyper echogenic rim. All malignant nodules (137) were papillary carcinomas, which were studied to identify the correlation between the hyper-echoic rim (detected by ultrasound) and other histologic features. Presence of a hyper-echoic rim had high specificity (94.51%), but low sensitivity (31.39%) in predicting malignancy (p < 0.05). Thirty-seven of 43 malignant nodules had boundary zones of mixed structure (apparent fibrous stroma bands or dense collagenous border with a mixed population of cancerous cells) under microscopic examination. In conclusion, the hyper-echogenic rim could be one additional ultrasound parameter in the diagnosis of thyroid lesions. [ABSTRACT FROM AUTHOR]

Fusarium verticillioides is a key maize pathogen and produces fumonisins, a group of mycotoxins detrimental to humans and animals. Unfortunately, our understanding on how this fungus interacts with maize to trigger mycotoxin biosynthesis is limited. We performed a systematic computational network-based analysis of large-scale F. verticillioides RNA-seq datasets to identify gene subnetwork modules associated with virulence and fumonisin regulation. F. verticillioides was inoculated on two different maize lines, moderately resistant line hybrid 33K44 and highly susceptible line maize inbred line B73, to generate time-course RNA-Seq data. Among the highly discriminative subnetwork modules, we identified a putative hub gene FvLCP1 , which encodes a putative a type-D fungal LysM protein with a signal peptide, three LysM domains, and two chitin binding domains. FvLcp1 is a unique protein that harbors these domains amongst five representative Fusarium species. FvLcp1 is a secreted protein important for fumonisin production with the LysM domain playing a critical role. The chitin-binding domain was essential for in vitro chitin binding. Using Magnaporthe oryzae , we learned that FvLcp1 accumulates in appressoria, suggesting that FvLcp1 is involved in host recognition and infection. Full length FvLcp1 suppressed BAX-triggered plant cell death in Nicotiana benthamiana. This unique type-D LysM secreted protein with a chitin-binding domain in F. verticillioides was shown to be potentially involved in suppressing host cell death and promoting fumonisin biosynthesis while the pathogen colonizes maize kernels. [ABSTRACT FROM AUTHOR]

[Display omitted] • Size-controllable copper-silver core–shell nanoparticles were synthesized. • The nanoparticles could remain steady in air for 40 days and at 156℃. • Its electrochemical failure time was 4.6 times higher than sintered silver. • The novel sintering mechanism generated by 'dewetting' behavior was proposed. • Its ultralow resistivity was only up to 3.21 μΩ∙cm even sintered at 140 °C. Metallic conductive nanoink with the sensitivity of temperature, oxygen, and electrochemical migration is a great challenge for printed electronics. Here, the size-controllable Cu@Ag core–shell nanoparticles (NPs) conductive films with effective cost, excellent electrical conductivity, high electrochemical migration (ECM) and oxidation resistance were obtained successfully. The novel mechanism of lower temperature sintering for Cu@Ag NPs was proposed due to radius of curvature between a large amount of tiny Ag nanobumps generated by 'dewetting' behavior. The Cu@Ag NPs also exhibited extreme ECM and oxidation resistance. It could remain steady in air for 40 days and hardly oxide at a high temperature of 156℃, and its failure time of ECM was 4.6 times higher than that of Ag NPs. Besides, the resistivity was up to 3.21 μΩ∙cm (55% of the bulk conductivity of Cu) even sintered at 140 °C, which enjoyed a great advantage. Ultimately, serial flexible organic light emitting diodes were integrated by high precision inkjet printing, and their excellent bending resistance and printable performance were fully exhibited. Accordingly, integrating the advantages of controllable nanoscale, lower temperature sintering, optimized conductivity, high antioxidation, excellent ECM resistance, flexibility, and printability, we enlighten the practical applications of flexible printed electronics. [ABSTRACT FROM AUTHOR]

Highlights: [•] Purified & identified novel antioxidative peptides from oyster protein hydrolysate. [•] The novel peptides are Pro-Val-Met-Gly-Asp and Gln-Hist-Gly-Val. [•] Novel technique nano-ESI-MS/MS applied to analyse the amino acid sequences. [•] Determined optimum protein hydrolytic reaction conditions using subtilisin. [•] Findings assist Chinese industry in utilizing cheap source of bioactive materials. [Copyright &y& Elsevier]

Abstract: Rare earth nanoparticles (RENPs) have great superiority as luminescent materials for broad applications, and a prerequisite for most of their application is to obtain hydrophilic RENPs with efficient luminescence and small diameter (<10nm). To address this problem, we report a facile one-pot sonochemical route with tetraethylene glycol as the solvent and tetrafluoroborate-based ionic liquid as the fluorine source for the synthesis of LaF3:Ce,Tb as the model of RENPs. LaF3:Ce,Tb nanoparticles with the diameter of about 6nm were prepared in a very short ultrasound time (10min). Fourier transform infrared spectrum reveals the presence of tetraethylene glycol ligands on their surface, which confers high solubility of LaF3:Ce,Tb nanoparticles in water. Under 254nm UV excitation, the aqueous dispersion of LaF3:Ce,Tb nanoparticles exhibits strong green emission with luminescent quantum yield of ∼50%. This work probably contributes to not only the fundamental research of shape-controlled LaF3:Ce,Tb nanoparticles but also new methods of producing other RENPs for broad applications. [Copyright &y& Elsevier]

Abstract: Cathodic protection (CP) is usually combined with organic coatings to protect metallic structures exposed to seawater. However, the application of CP would enhance coating failure, such as cathodic delamination. To date, there has been few works characterizing the impedance models and water transport behaviors of cathodically polarized coating. In the present article, the analyses of impedance models and water uptake processes of chlorinated rubber coating subjected to various levels of cathodic protection were studied during coatings aging process by electrochemical impedance spectroscopy (EIS). Four distinguished electrical equivalent circuits (EEC) were used to fit the EIS plots of coatings without CP, while only two were employed for samples with CP. Since no corrosion was expected to take place at the metal/coating interface for sample which was polarized cathodically. Coating capacitance was used to investigate the sorption characteristic of water in coating since the increase of C c was associated with water penetration into the coating. Compared with the sample without CP, those coating systems under CP have a smaller water diffusion coefficient and a further water uptake process after the saturation period. [Copyright &y& Elsevier]