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As a carbon-free fuel, hydrogen has received significant attention recently since it can help enable low-carbon-economy. Hydrogen has very broad flammability range and very low minimum ignition energy, and thereby there are severe safety concerns for hydrogen transportation and utilization. Cryo-compressed hydrogen is popularly used in practice. Therefore, it is necessary to investigate the combustion properties of hydrogen at extremely low or cryogenic temperatures. This study aims to assess and interpret the effects of cryogenic temperature on premixed hydrogen/air flame propagation and acceleration in a thin closed channel. Different initial temperatures ranging from normal temperature (T 0 = 300 K) to cryogenic temperature (T 0 = 100 K) are considered. Both one- and two-dimensional hydrogen/air flames are investigated through transient simulations considering detailed chemistry and transport. It is found that when the initial temperature decreases from T 0 = 300 K to T 0 = 100 K, the expansion ratio and equilibrium pressure both increase substantially while the laminar flame speeds relative to unburned and burned gasses decrease moderately. The one-dimensional flame propagation is determined by laminar flame speed and thereby the combustion duration increases as the initial temperature decreases. However, the opposite trend is found to happen to two-dimensional flame propagation, which is mainly controlled by the flame surface area increase due to the no-slip side wall constraint and flame instability. Based on the change in flame surface area, three stages including the initial acceleration, steady burning and rapid acceleration are identified and investigated. It is demonstrated that the large expansion ratio and high pressure rise at cryogenic temperatures can significantly increase the flame surface area in early stage and promote both Darrieus-Landau instability (hydrodynamic instability) and Rayleigh-Taylor instability in later stage. These two instabilities can substantially increase the flame surface area and thereby accelerate flame propagation in hydrogen/air mixtures at cryogenic temperatures. The present study provides useful insights into the fundamental physics of hydrogen flames at extremely low temperatures, and is closely related to hydrogen safety. [ABSTRACT FROM AUTHOR]

Aims: This study systematically evaluated cases of pneumonitis following combined immune checkpoint inhibitors (ICI) and chemoradiotherapy (CRT) for locally advanced non-small-cell lung cancer (LA-NSCLC). Methods: Studies from Embase, PubMed and the Cochrane Library on patients with LA-NSCLC who received CRT and ICIs were reviewed. The primary outcomes were rates of all-grade, grade 3–5 and grade 5 pneumonitis. Results: Overall, 35 studies involving 5000 patients were enrolled. The pooled rates of all-grade, grade 3–5 and grade 5 pneumonitis were 33.0% (95% CI: 23.5–42.6), 6.1% (95% CI: 4.7–7.4) and 0.8% (95% CI: 0.3–1.2), respectively, with 7.6% of patients discontinuing ICIs because of pneumonitis. Conclusion: The incidence rates of pneumonitis following combined CRT and ICIs for LA-NSCLC were acceptable. However, the pulmonary toxicity of concurrent CRT and nivolumab plus ipilimumab should be noted. Combined immune checkpoint inhibitors (ICI) and chemoradiotherapy (CRT) may cause severe pneumonitis due to overlapped pulmonary toxicity. However, the safety data on pneumonitis are limited to a small number of prospective clinical trials and retrospective studies with limited evidence. Thus we conducted a systematic review of pneumonitis in relation to the combination treatment. A total of 35 studies, involving 5000 patients, were included for the final analysis. The pooled rates of all-grade, grade 3–5 and grade 5 pneumonitis were 33.0, 6.1 and 0.8%, respectively, and 7.6% of patients stopped taking ICIs because of pneumonitis. The pneumonitis rates following combined CRT and ICIs for LA-NSCLC were acceptable, but the pulmonary toxicity of concurrent CRT and nivolumab plus ipilimumab should be noted. [ABSTRACT FROM AUTHOR]

Background: Most nursing interns have suffered some form of workplace violence in clinical settings, which has been linked to the jeopardizing of patient safety. Although previous research studies have examined the effect of workplace violence on patient safety, few studies have examined whether workplace violence is associated with patient safety through professional identity and professional burnout among nursing interns. Aims: To test whether professional identity and professional burnout play mediating roles in the relationship of workplace violence and patient safety among nursing interns. Design: Cross‐sectional study. Methods: The study included 466 nursing interns from three tertiary grade A hospitals. The Workplace Violence Scale, the Professional Identity Scale, the Maslach Burnout Inventory‐General Survey, and the Patient Safety Behaviour Scale were used to gather data. Associations among workplace violence, professional identity, professional burnout, and patient safety were assessed by correlation and the serial‐multiple mediation analysis. Results: Workplace violence, professional identity, professional burnout and patient safety were significantly correlated. Workplace violence can have a direct positive impact on patient safety of nursing interns, but also an indirect impact on patient safety through three paths: the independent mediating role of professional identity, the independent mediating role of professional burnout, and the chain mediating role of professional identity and professional burnout. Conclusions: Our findings suggest that workplace violence can affect patient safety through decreasing professional identity and increasing professional burnout among nursing interns. Interventions aimed at decreasing workplace violence among nursing interns would be beneficial for professional attitude and patient safety. [ABSTRACT FROM AUTHOR]

Background. The poor prognosis of the highly malignant tumor osteosarcoma stems from its drug resistance and therefore exploring its resistance mechanisms will help us identify more effective treatment options. However, the effects of miR-125b-5p on drug resistance in osteosarcoma cells are still unclear. Methods. To study the effects of miR-125b-5p on drug resistance in osteosarcoma cells. Osteosarcoma-resistant miR-125b-5p was obtained from the databases GeneCards and g:Profiler. CCK8, western blot, and transwell were applied for the detection of the miR-125b-5p effects on proliferation, migration, invasion, apoptosis, and drug resistance in osteosarcoma. Bioinformatics is aimed at demonstrating the targeting factor miR-125b-5p, performing protein interaction enrichment analysis by Metascape, and finally validating by binding sites. Results. Upregulation of miR-125b-5p restrains proliferation, migration, and invasion of osteosarcoma and promotes apoptosis. In addition, miR-125b-5p can restore drug sensitivity in drug-resistant osteosarcoma. miR-125-5p restrains the signal transducer and inhibits the transcription 3 (STAT3) expression activator via targeting its 3 ′ -UTR. STAT3 affects drug-resistant osteosarcoma to regulate the ABC transporter. Conclusion. miR-125b-5p/STAT3 axis mediates the drug resistance of osteosarcoma by acting on ABC transporter. [ABSTRACT FROM AUTHOR]

Polydopamine fluorescent organic nanomaterials present unique physicochemical and biological properties, which have great potential application in bio-imaging and chemical sensors. Here, folic acid (FA) adjustive polydopamine (PDA) fluorescent organic nanoparticles (FA-PDA FONs) were prepared by a facile one-pot self-polymerization strategy using dopamine (DA) and FA as precursors under mild conditions. The as-prepared FA-PDA FONs had an average size of 1.9 ± 0.3 nm in diameter with great aqueous dispersibility, and the FA-PDA FONs solution exhibit intense blue fluorescence under 365 nm UV lamp, and the quantum yield is ~8.27%. The FA-PDA FONs could be stable in a relatively wide pH range and high ionic strength salt solution, and the fluorescence intensities are constant. More importantly, here we developed a method for rapidly selective and sensitive detection of mercury ions (Hg2+) within 10 s using FA-PDA FONs based probe, the fluorescence intensities of FA-PDA FONs presented a great linear relationship to Hg2+ concentration, the linear range and limit of detection (LOD) were 0–18 µM and 0.18 µM, respectively. Furthermore, the feasibility of the developed Hg2+ sensor was verified by determination of Hg2+ in mineral water and tap water samples with satisfactory results. [ABSTRACT FROM AUTHOR]

The corrosion of carbon steel causes dramatic economic losses each year. Since conventional corrosion prevention approaches may cause pollution problems to the environment, ecofriendly and effective corrosion approaches are desired. Microbiologically influenced corrosion inhibition (MICI) has been reported as a sustainable corrosion prevention method. This work aims to evaluate the corrosion inhibition effect of two bacterial strains, Tenacibaculum mesophilum D-6 and Bacillus sp. Y-6 by choosing Q235 carbon steel as a model system. Scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM) and a series of electrochemical techniques were applied to study the corrosion prevention effect. The electrochemical and pitting results indicated that T. mesophilum D-6 displayed a better corrosion protection effect. T. mesophilum D-6 formed a denser and thicker biofilm on the Q235 surface than Bacillus sp. Y-6. The maximum thickness of the T. mesophilum D-6 biofilms was 11.6 ± 0.7 μm, which is about twice as thick than that of Bacillus sp. Y-6. The corrosion prevention mechanism was ascribed to the formation of biofilms as a barrier to block corrosive agents such as O2. This study provides a theoretical foundation for the application of biofilms as green and effective corrosion inhibitors for carbon steel. [ABSTRACT FROM AUTHOR]

Recently, multiple spark ignition has received great attention since it helps to increase thermal efficiency and to reduce misfire in engines. Multiple spark ignition also affects the combustion duration and thereby it can be used for knock control. However, previous studies reported opposite trends in terms of how multiple spark ignition affects engine knock. This work aims to assess and interpret the influence of flame propagation direction induced by different ignition configurations on combustion duration and end-gas autoignition/engine knock. Two simplified and idealised ignition configurations are studied theoretically and numerically. One is with infinite number of sparks at side circular wall, which induces an inwardly propagating flame (IPF); and the other is with a single central spark, which induces an outwardly propagating flame (OPF). In the asymptotic theoretical analysis, the canonical 1D formulations for IPF and OPF are reduced to 0D model. Based on the 0D model, OPF and IPF at different initial temperatures are studied and compared. Counterintuitively, it is found that the combustion duration of OPF is shorter than that of IPF when there is no end-gas autoignition. On the other hand, the combustion duration of IPF is shorter than that of OPF when end-gas autoignition occurs. Furthermore, end-gas autoignition is found to be more prone to occur in IPF than OPF. These interesting observations are interpreted through assessing the ignition delay time and different components of the absolute flame propagation speed. The theoretical results are validated by transient simulations considering detailed chemistry and transport which are conducted for IPF and OPF in an iso-octane/air mixture at different initial temperatures and pressures. Both theoretical and numerical results suggest that compared to infinite number of ignition sparks at side wall, the single central ignition has the advantages in shortening the combustion duration and reducing the tendency of end-gas autoignition. [ABSTRACT FROM AUTHOR]

The harvesting period is a critical period for the accumulation of flavonoids in the leaves of the important medicinal plant Epimedium sagittatum. In this study, we conducted an experiment on E. sagittatum leaves sprayed with mineral elements with the aim of improving the quality of the herbal leafage during the harvesting period. We elucidated the changes in flavonoids (icariin, epimedin A, epimedin B, and epimedin C) in E. sagittatum leaves. The sum of main flavonoids content reached a maximum (11.74%) at 20 days after the high-concentration Fe2+ (2500 mg·L−1) treatment. We analyzed the FT-IR spectra characteristics of E. sagittatum leaf samples using the FT-IR technique, and constructed an OPLS-DA model and identified characteristic peaks to achieve differentiated identification of E. sagittatum. Further, widely untargeted metabolomic analysis identified different classes of metabolites. As the most important characteristic flavonoids, the relative contents of icariin, icaritin, icariside I, and icariside II were found to be up-regulated by high-Fe2+ treatment. Our experimental results demonstrate that high-concentration Fe2+ treatment is an effective measure to increase the flavonoids content in E. sagittatum leaves during the harvesting period, which can provide a scientific basis for the improvement of E. sagittatum leaf cultivation agronomic measures. [ABSTRACT FROM AUTHOR]

Purpose: We assess real-world outcomes, including safety and efficacy, of concurrent or sequential treatment with radiotherapy plus programmed cell death protein 1 (PD-1) inhibitors in patients with oligometastatic esophageal cancer (OMEC). Methods: This cohort study retrospectively collected clinical data of patients with synchronous or metachronous OMEC. All patients underwent concurrent or sequential treatment with radiotherapy plus PD-1 inhibitors. Each patient had up to five measurable metastatic lesions and up to three organs involved. Study endpoints were progression-free survival (PFS), treatment-related toxicities, locoregional progression-free survival (LRPFS), objective response rate (ORR), and disease control rate (DCR). Description statistics and Kaplan–Meier models were used for statistical analysis. Results: A total of 86 patients were included, most of whom were diagnosed with squamous cell carcinoma histology (98%) and presented with synchronous OMEC (64%). The median follow-up period was 17 months (range: 6– 32 months), the median PFS was 15.2 months (95% confidence interval: 12.1– 18.2 months); and the 1- and 2-year PFS rates were 61.4% and 26.7%, respectively. The 1- and 2-year LRPFS were 91.3% and 57.3%, respectively. The ORR and DCR were 46.5% and 91.8%, respectively. Forty-two patients (48.8%) experienced grade 3 or higher treatment-related adverse events (TRAEs); a grade 5 treatment-related adverse event was observed in one patient (1.2%) who died of immune-related pneumonitis. Conclusion: Combining radiotherapy with PD-1 inhibitors is a safe and effective treatment option for patients with OMEC. No new safety concerns were identified in this study. However, due to the potential risk of cumulative toxicity, an individual risk-benefit assessment for each patient is required prior to treatment initiation. [ABSTRACT FROM AUTHOR]

In this paper, an improved VGG16 combined with depthwise group over-parameterized convolution (DGOVGG16) model is proposed to realize automatic furniture image classification. Firstly, depthwise over-parameterized convolution combined with group convolution is combined to construct depthwise group over-parameterized convolution, which is introduced to the VGG 16 model for reducing the number of parameters of the overall model while extracting more sufficient semantic features of furniture images. Then, this paper uses the ReLU activation function in the former part of the neural network to reduce the correlation between parameters and accelerate the weight update speed of the former part of the model. Meantime, the proposed model applies Leaky-ReLU activation function in the last layer to avoid the problem that some neurons do not update. Compared with the six furniture image classification methods based on MobileNetV2, AlexNet, ShuffleNetv2, GoogleNet, VGG 16 and GVGG16, the experimental results show the proposed DGOVGG16 with average accuracy (AA) of 95.51% has better classification performance. [ABSTRACT FROM AUTHOR]

Previous studies have shown that low birth weight (LBW) individuals are at higher risk of glucose metabolism disorders compared with normal birth weight (NBW) individuals under overnutrition conditions, but the mechanism remains unclear. To explore the underlying mechanism of glucose metabolism disorders induced by LBW under overnutrition in adulthood, the prenatal malnutrition method was applied to ICR mice to establish the LBW mice model and high-fat diets were used to mimic overnutrition conditions. Then the mechanism was further explored on Hepg2 cells treated with nutritional deprivation plus palmitic acid. The results showed that LBW plus high-fat interventions will cause glucose metabolism disorders and inhibit autophagy flux in adulthood. Moreover, the expression of TRPC5-regulated AMPK/mTOR autophagy pathway was downregulated by LBW with high-fat interventions. Collectively, LBW plus high-fat intervention increased the risk of glucose metabolism disorders, which may be related to the alteration of TRPC5 expression level and its regulation of the AMPKα/mTOR autophagy pathway. This study may provide a fundamental basis for the molecular mechanism of glucose metabolism disorders induced by LBW with high-fat diets in adulthood and a new target for the treatment of metabolic diseases in LBW individuals. • LBW mice induced by a high-fat diet are more prone to glucose metabolic disorders in adulthood. • The LBW mice model was established by the prenatal malnutrition method with a high-fat diet to explore the possible mechanism of metabolic disorders induced by LBW. • The mechanism was further explored on Hepg2 cells treated with nutritional deprivation plus palmitic acid. • Glucose metabolic disorders induced by LBW may be related to the alteration of TRPC5 expression level and its regulation of the CaMKKβ/AMPKα/mTOR autophagy pathway. [ABSTRACT FROM AUTHOR]

Background: Accurate prognostic prediction plays a crucial role in the clinical setting. However, the TNM staging system fails to provide satisfactory individual survival prediction for stage III non‐small cell lung cancer (NSCLC). The performance of the deep learning network for survival prediction in stage III NSCLC has not been explored. Objectives: This study aimed to develop a deep learning‐based prognostic system that could achieve better predictive performance than the existing staging system for stage III NSCLC. Methods: In this study, a deep survival learning model (DSLM) for stage III NSCLC was developed based on the Surveillance, Epidemiology, and End Results (SEER) database and was independently tested with another external cohort from our institute. DSLM was compared with the Cox proportional hazard (CPH) and random survival forest (RSF) models. A new prognostic system for stage III NSCLC was also proposed based on the established deep learning model. Results: The study included 16,613 patients with stage III NSCLC from the SEER database. DSLM showed the best performance in survival prediction, with a C‐index of 0.725 in the validation set, followed by RSF (0.688) and CPH (0.683). DSLM also showed C‐indices of 0.719 and 0.665 in the internal and real‐world external testing datasets, respectively. In addition, the new prognostic system based on DSLM (AUROC = 0.744) showed better performance than the TNM staging system (AUROC = 0.561). Conclusion: In this study, a new, integrated deep learning‐based prognostic model was developed and evaluated for stage III NSCLC. This novel approach may be valuable in improving patient stratification and potentially provide meaningful prognostic information that contributes to personalized therapy. [ABSTRACT FROM AUTHOR]

The larval distributions of the small-sized fishes Omobranchus elegans, Erisphex pottii, Benthosema pterotum, Acropoma japonicum, Upeneus bensasi, and Apogonichthys lineatus in the East China Sea ecosystem are important due to their ecological and economic benefits. To date, however, there have been few studies describing their population distributions and dynamics. In the current study, ichthyoplankton surveys were carried out from April to July 2018 to analyze variations in the larval abundance, distribution, and development stages of these species. In addition, the spatiotemporal larval distribution was investigated in terms of measured environmental variables. It was found that larvae were mainly distributed at depths of 5.00–66.00 m, in areas with sea surface temperature of 4.40–29.60 °C, sea surface salinity of 16.54–34.60 psu, pH of 7.00–9.00, and dissolved oxygen concentration of 2.54–8.70 mg/L. Benthosema pterotum and A. lineatus migrated from 30.00–31.00° N 123.17–123.50° E in June to 30.00–32.50° N 122.22–123.50° E in July. The results of this study can help to preserve spawning and nursery grounds and contribute to sustainable coastal fisheries management. [ABSTRACT FROM AUTHOR]

Sargassum beds ensure sustainable environmental, social, and economic benefits in the coastal areas around the world. They can provide shelter ground to different species of fish juveniles. To investigate these, we conducted field surveys in a peaking growth period of Sargassum horneri from May to June 2010 to evaluate them on Gouqi Island, Ma'an archipelago, China. The study indicated that the light attenuation rate inside the S. horneri beds was higher than that in the surrounding areas. The light attenuation rate was highest in Ganxie, the second highest in Huangshidong, and the lowest in Houtouwan. We found that the average length of Sebastiscus marmoratus corresponded to the average height of S. horneri. This study improves our understanding of the function of sheltering grounds provided by Sargassum beds. Additionally, this study is relevant to the development of the regulations and directives to ensure the sustainable exploitations and protection of wild seaweeds and the accompanying organisms resources. [ABSTRACT FROM AUTHOR]

Calcium signalling in platelets through store operated Ca2+ entry (SOCE) or receptor-operated Ca2+ entry (ROCE) mechanisms is crucial for platelet activation and function. Orai1 proteins have been implicated in platelet's SOCE. In this study we evaluated the contribution of Orai1 proteins to these processes using washed platelets from adult mice from both genders with platelet-specific deletion of the Orai1 gene (Orai1flox/flox; Pf4-Cre termed as Orai1Plt-KO) since mice with ubiquitous Orai1 deficiency show early lethality. Platelet aggregation as well as Ca2+ entry and release were measured in vitro following stimulation with collagen, collagen related peptide (CRP), thromboxane A2 analogue U46619, thrombin, ADP and the sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) inhibitor thapsigargin, respectively. SOCE and aggregation induced by Thapsigargin up to a concentration of 0.3 µM was abrogated in Orai1-deficient platelets. Receptor-operated Ca2+-entry and/or platelet aggregation induced by CRP, U46619 or thrombin were partially affected by Orai1 deletion depending on the gender. In contrast, ADP-, collagen- and CRP-induced aggregation was comparable in Orai1Plt-KO platelets and control cells over the entire concentration range. Our results reinforce the indispensability of Orai1 proteins for SOCE in murine platelets, contribute to understand its role in agonist-dependent signalling and emphasize the importance to analyse platelets from both genders. [ABSTRACT FROM AUTHOR]

As an important medicinal plant, we still do not know the effect of exogenous hormones on absorption of elements and accumulation of secondary metabolites in Artemisia argyi leaves. In this work, we analyzed the difference in 21 elements absorbed by A. argyi leaves under three exogenous hormone (MeJA, SA and ABA) treatments, and also clarified the correlation between 21 elements and eight bioactive components. Different hormone treatments changed the absorption and enrichment of elements, and the composition also changed significantly. The contents of eight bioactive components changed significantly under different hormone treatments. When A. argyi was stimulated by exogenous hormones, the content of secondary metabolites was adjusted in the leaves through changes in the absorption and enrichment of elements. The widely untargeted metabolomic analysis further confirmed that ABA changes the metabolic direction of secondary metabolites in A. argyi leaves and stimulates the biosynthesis of multiple secondary metabolites including phenylpropanoids, flavonoids, terpenoids, alkaloids and others. These results provide a new perspective for the changes in element absorption and the mechanism of secondary metabolic components in A. argyi leaves under exogenous hormone treatments, and also deepen people's understanding of the interaction mechanism between medicinal plants and hormones. [ABSTRACT FROM AUTHOR]

Bacterial fruit blotch (BFB) is a disease of cucurbit plants caused by Acidovorax citrulli. Although A. citrulli has great destructive potential, the molecular mechanisms of pathogenicity of A. citrulli are not clear, particularly with regard to its type III secreted effectors. In this study, we characterized the type III secreted effector protein, AopV, from A. citrulli strain Aac5. We show that AopV significantly inhibits reactive oxygen species and the expression of PTI marker genes, and helps the growth of Pseudomonas syringae D36E in Nicotiana benthamiana. In addition, we found that the aromatic dehydratase ADT6 from watermelon was a target of AopV. AopV interacts with ADT6 in vivo and in vitro. Subcellular localization indicated ADT6 and AopV were co-located at the cell membrane. Together, our results reveal that AopV suppresses plant immunity and targets ADT6 in the cell membrane. These findings provide an new characterization of the molecular interaction of A. citrulli effector protein AopV with host cells. [ABSTRACT FROM AUTHOR]

The combination of electrokinetic (EK) and permeable reactive barrier (PRB) is a potentially effective technology for the remediation of heavy-metal-contaminated soils, but high energy expenditure limits its application in practice. In order to further improve the remediation efficiency and reduce the cost, some improvements were made in this study in terms of new PRB material, the spatial configuration of the rod electrode, and the microbial enhancement. Differently from previous powder PRB materials, six thin-film PRB materials were prepared using cheap natural attapulgite (ATP) and metal salts. PRB is a tough material that can be plugged and pulled out in engineering. The heavy metals adsorbed on it can be extracted from the soil, eliminating the risk of subsequent secondary pollution. Therefore, it has a strong operational ability. Among them, the FeMn-ATP material exhibited the best adsorption performance (2521 ± 377.1 mg/kg) for Pb. The results of the transmission electron microscope, X-ray diffractometer, and Fourier-transform infrared spectroscopy showed that iron and manganese were successfully loaded on the material. The Burkholderia cepacia pre-treatment led to soil pH decrease and the dissolution of Pb, and the morphological composition of Pb in the soil was also changed. In the microbial group, the adsorption amount of Pb by PRB at the anode and cathode increased by 69.1% and 42.1%, respectively. The concentration of the residual lead in the anode soil was significantly lower than that in the control group without microorganisms, and the removal rate of Pb was increased by 26%. [ABSTRACT FROM AUTHOR]