Arsenic, Cd, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn total concentrations and bioaccessibilities in 15 urban park dust samples were determined. The oral bioaccessibility measured by the Simple ...Bioaccessibility Extraction Test (SBET) decreased in the order of Pb>Cd>Zn>Mn>Cu>Co>V>Ni>As>Cr. The Tomlinson pollution load index (PLI) and geoaccumulation index (Igeo) were calculated to evaluate the pollution extent to which the samples were contaminated. Sources were identified using principal component analysis and Pb isotope compositions. Most elements except Co and V were considered to mainly originate from anthropogenic sources. Non-carcinogenic and carcinogenic risks to humans through urban park dust exposure were assessed using the oral bioaccessibilities of the elements. Ingestion was the main pathway for non-carcinogenic risk. The hazard quotients were below the safe level (=1) for all elements, however, Pb (0.154) and As (0.184) posed potential higher risks to children than adults. The carcinogenic effects occurring were below the acceptable level (10−4) for As and <10−6 for Cd, Co, Cr, and Ni.
Display omitted
•Bioaccessibility of trace metal was measured in urban park dust of Nanjing.•Sources of trace metals in dust were identified using Pb isotopes and PCA.•Human health risk was assessed combining with the SBET-extractable results of elements.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The aim of the present study was to assess the toxic effects of pyraclostrobin on DNA damage and antioxidant enzymatic activities in the zebrafish (Danio rerio) liver. Based on the 96-h median lethal ...concentration (96 h LC50, 0.056 mg/L) of this chemical, fish were exposed to three doses (0.001, 0.01, and 0.02 mg/L) and sampled on days 7, 14, 21 and 28 after the initiation of a subchronic toxicity test. The levels of superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), glutathione S-transferase (GST), reactive oxygen species (ROS) and DNA damage were determined. The amount of pyraclostrobin residue in the water was also measured. The concentrations in the three treatment groups varied no more than 5% during the exposure periods, indicating that pyraclostrobin is relatively stable during this time in an aquatic environment. ROS and MDA levels significantly changed in a dose dependent manner during the experiment. Enzymatic activities were inhibited to a certain extent. DNA damage was significantly enhanced. These results collectively indicate that pyraclostrobin induces oxidative stress and DNA damage in zebrafish.
•Acute and subchronic toxic effects of pyraclostrobin on zebrafish were investigated.•Pyraclostrobin can cause oxidative stress and oxidative damage in zebrafish.•The comet assay was the most sensitive of all biomarkers used in the present study.•The doses of pyraclostrobin are at a relatively stable level in the present study.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Non-regression-based inferences, such as discriminant analysis, can account for the effect of predictor distributions that may be significant in big data modeling. We describe bbl, an R package for ...Boltzmann Bayes learning, which enables a comprehensive supervised learning of the association between a large number of categorical predictors and multi-level response variables. Its basic underlying statistical model is a collection of (fully visible) Boltzmann machines inferred for each distinct response level. The algorithm reduces to the naive Bayes learner when interaction is ignored. We illustrate example use cases for various scenarios, ranging from modeling of a relatively small set of factors with heterogeneous levels to those with hundreds or more predictors with uniform levels such as image or genomic data. We show how bbl explicitly quantifies the extra power provided by interactions via higher predictive performance of the model. In comparison to deep learning-based methods such as restricted Boltzmann machines, bbl-trained models can be interpreted directly via their bias and interaction parameters.
In the last five years, China has seen the technological development of intelligent mining and the application of the longwall automation technology developed by the Longwall Automation Steering ...Committee. This paper summarizes this great achievement, which occurred during the 12th Five-Year Plan （2011-2015）, and which included the development of a set of intelligent equipment for hydraulic-powered supports, information transfers, dynamic decision-making, performance coordination, and the achievement of a high level of reliability despite difficult conditions. Within China, the intelligent system of a set of hydraulic-powered supports was completed, with our own intellectual property rights. An intelligent mining model was developed that permitted unmanned operation and single-person inspection on the work face. With these technologies, the number of miners on the work face can now be significantly reduced. Miners are only required to monitor mining machines on the roadway or at the surface control center, since intelligent mining can be applied to extract middle-thick or thick coal seams. As a result, miners＇ safety has been improved. Finally, this Darter discusses theprospects and challenges of intelligent mining over the next ten years.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The programmed cell death 1 (PD-1) receptor on the surface of immune cells is an immune checkpoint molecule that mediates the immune escape of tumor cells. Consequently, antibodies targeting PD-1 ...have shown efficacy in enhancing the antitumor activity of T cells in some types of cancers. However, the potential effects of PD-1 on tumor cells remain largely unknown. Here, we show that PD-1 is expressed across a broad range of tumor cells. The silencing of PD-1 or its ligand, PD-1 ligand 1 (PD-L1), promotes cell proliferation and colony formation in vitro and tumor growth in vivo. Conversely, overexpression of PD-1 or PD-L1 inhibits tumor cell proliferation and colony formation. Moreover, blocking antibodies targeting PD-1 or PD-L1 promote tumor growth in cell cultures and xenografts. Mechanistically, the coordination of PD-1 and PD-L1 activates its major downstream signaling pathways including the AKT and ERK1/2 pathways, thus enhancing tumor cell growth. This study demonstrates that PD-1/PD-L1 is a potential tumor suppressor and potentially regulates the response to anti-PD-1/PD-L1 treatments, thus representing a potential biomarker for the optimal cancer immunotherapeutic treatment.
Full text
Available for:
BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
The self-acceleration of spherically expanding flames were investigated using a constant volume combustion chamber for CO/H2/O2/N2 mixtures over a wide range of initial pressure from 0.2 to 0.6 MPa, ...CO/H2 ratio from 50/50 to 10/90 and equivalence ratio from 0.4 to 1.5. The adiabatic flame temperature was kept constant by adjusting O2/N2 ratio at different equivalence ratios. Schlieren images were recorded to investigate the flame front evolution of spherically expanding flames. Local acceleration exponents were extracted using a proper equation to study the process of flame self-acceleration. Results show that the flame cells develop on the smooth flame fronts and finally reach fractal-like structures due to the hydrodynamic and diffusional-thermal instabilities, resulting in flame self-accelerative propagation. The critical Peclet number corresponding to the onset of self-acceleration, Pecr increases nonlinearly with the Markstein length, Ma. The observation further reveals that the onset of self-acceleration is mainly controlled by the diffusional-thermal effect. There exists two distinct flame propagation regimes in the self-acceleration, namely quick transition accelerative and quasi self-similar accelerative regimes. The quick transition regime is controlled by the destabilization effect of hydrodynamic perturbation and stabilization effect of flame stretch. While the quasi self-similar regime is primarily affected by the cascading process of flame front cells controlled by hydrodynamic instability. The self-similar acceleration exponent, αs varies with the initial pressure and Lewis number, Le. The values of αs are measured to be 1.1–1.25 (smaller than 1.5), indicating the flame dose not attain self-turbulization.
•Effects of intrinsic instability on flame front evolution were investigated systematically.•Three distinct regimes in flame propagation were observed and analyzed in detail.•Critical onset and transition Peclet numbers in flame self-acceleration were obtained.•Accurate self-similar acceleration exponent of syngas flames was measured.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
A population of Natural Killer (NK) cells expressing the activating receptor NKG2C and the maturation marker CD57 expands in response to human cytomegalovirus (HCMV) infection. CD3-CD56dimCD57+NKG2C+ ...NK cells are similar to CD8+ memory T cells with rapid and robust effector function upon re-stimulation, persistence, and epigenetic remodeling of the IFNG locus. Chronic antigen stimulation drives CD8+ memory T cell proliferation while also inducing genome-wide epigenetic reprograming and dysfunction. We hypothesized that chronic stimulation could similarly induce epigenetic reprograming and dysfunction in NK cells. Here we show that chronic stimulation of adaptive NK cells through NKG2C using plate-bound agonistic antibodies in combination with IL-15 drove robust proliferation and activation of CD3-CD56dimCD57+NKG2C+ NK cells while simultaneously inducing high expression of the checkpoint inhibitory receptors LAG-3 and PD-1. Marked induction of checkpoint inhibitory receptors was also observed on the surface of adaptive NK cells co-cultured with HCMV-infected endothelial cells. Chronically stimulated adaptive NK cells were dysfunctional when challenged with tumor targets. These cells exhibited a pattern of epigenetic reprograming, with genome-wide alterations in DNA methylation. Our study has important implications for cancer immunotherapy and suggest that exhausted NK cells could be targeted with inhibitory checkpoint receptor blockade.
Azoxystrobin is a frequently used fungicide in agriculture. Its toxicological effects on non-target organisms have aroused attention. In the present work, the toxic effects of azoxystrobin on ...zebrafish (Danio rerio) were investigated. Male and female zebrafish were separately exposed to a control solution and three azoxystrobin treatments (1, 10, and 100μg/L) and were sampled on days 7, 14, 21, and 28. Reactive oxygen species (ROS) were accumulated in excess in the zebrafish livers. Superoxide dismutase (SOD) activity was significantly inhibited in the male zebrafish. Moreover, a notable decrease was also observed after day 21 in the female zebrafish. Catalase (CAT) activity was induced by the azoxystrobin treatments with the exception of the 1μg/L treatment. A significant increase in glutathione-S-transferase (GST) activity was observed after day 21. Lipid peroxidation (LPO) was generated, and DNA damage was enhanced in a concentration-dependent manner. In conclusion, azoxystrobin induced oxidative stress and genotoxicity in zebrafish livers.
Display omitted
•Azoxystrobin induced oxidative stress and genotoxicity in zebrafish livers.•ROS was generated in excess.•SOD was inhibited, CAT and GST were stimulated at most azoxystrobin treatments.•Lipid peroxidation increased as a consequence of oxidative stress.•The excess ROS was one of the causes for the DNA damage.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Display omitted
Baicalein is the main active compound of Scutellaria baicalensis Georgi, a medicinal herb with multiple pharmacological activities, including the broad anti-virus effects. In this ...paper, the preclinical study of baicalein on the treatment of COVID-19 was performed. Results showed that baicalein inhibited cell damage induced by SARS-CoV-2 and improved the morphology of Vero E6 cells at a concentration of 0.1 μM and above. The effective concentration could be reached after oral administration of 200 mg/kg crystal form β of baicalein in rats. Furthermore, baicalein significantly inhibited the body weight loss, the replication of the virus, and relieved the lesions of lung tissue in hACE2 transgenic mice infected with SARS-CoV-2. In LPS-induced acute lung injury of mice, baicalein improved the respiratory function, inhibited inflammatory cell infiltration in the lung, and decreased the levels of IL-1β and TNF-α in serum. In conclusion, oral administration of crystal form β of baicalein could reach its effective concentration against SARS-CoV-2. Baicalein could inhibit SARS-CoV-2-induced injury both in vitro and in vivo. Therefore, baicalein might be a promising therapeutic drug for the treatment of COVID-19.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
DNA nanotechnology offers a versatile toolbox for precise spatial and temporal manipulation of matter on the nanoscale. However, rendering DNA‐based systems responsive to light has remained ...challenging. Herein, we describe the remote manipulation of native (non‐photoresponsive) chiral plasmonic molecules (CPMs) using light. Our strategy is based on the use of a photoresponsive medium comprising a merocyanine‐based photoacid. Upon exposure to visible light, the medium decreases its pH, inducing the formation of DNA triplex links, leading to a spatial reconfiguration of the CPMs. The process can be reversed simply by turning the light off and it can be repeated for multiple cycles. The degree of the overall chirality change in an ensemble of CPMs depends on the CPM fraction undergoing reconfiguration, which, remarkably, depends on and can be tuned by the intensity of incident light. Such a dynamic, remotely controlled system could aid in further advancing DNA‐based devices and nanomaterials.
The spatial configuration and optical properties of non‐photoresponsive DNA‐origami‐based plasmonic assemblies can be controlled with light using a photoresponsive medium. Upon exposure to visible light, the medium's pH decreases, inducing the formation of DNA triplex links in the plasmonic assemblies, leading to their spatial reconfiguration, which can be reversed by turning the light off.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
PDF
