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Abstract To address the problem of fault branch recognition in mine ventilation systems, a one-class classification algorithm is introduced to construct the MC-OCSVM ventilation system fault diagnosis model, which is integrated with multiple OCSVMs. This model adopts uniform hyperparameters and transforms the ventilation system fault diagnosis problem into a maximum decision distance problem, to realize the effective use of mine monitoring wind speed data. The experiments on public KEEL datasets verify that the one-class classification integration model can solve the multiclassification problem and that the MC-OCSVM model has better generalizability than other one-class classification integration models do. The experiment is carried out in the Buertai coal mine, and the results show that the proposed algorithm can identify fault branches quickly and accurately, with an accuracy of 93.2% and a single fault diagnosis time is 1.2 s, highlighting its strong robustness.

Abstract The relationship between serum uric acid and lung function has been controversial. This study aims to determine whether there is an independent relationship between serum uric acid and lung function in the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2012. Serum uric acid was considered the exposure variable, and lung function (FEV1 and FVC) was the outcome variable. Multivariable linear regression was conducted with adjustments for potential confounders. The total number of participants from NHANES (2007–2012) was 30,442, of which 7514 were included in our analysis after applying exclusion criteria. We observed that serum uric acid was negatively associated with FEV1 and FVC after adjusting for confounders (β for FEV1 [− 24.77 (− 36.11, − 13.43)] and FVC [− 32.93 (− 47.42, − 18.45)]). Similarly, serum uric acid showed a negative correlation with FEV1 and FVC after adjusting for confounding variables both in male and female populations. The relationship between serum uric acid and FEV1 and FVC remained consistent and robust in various subgroups within both male and female populations, including age, race, BMI, alcohol consumption, smoking status, and income-poverty ratio. Serum uric acid is negatively associated with FEV1 and FVC in the US general healthy population. This negative relationship is significant in both the male and female populations.

Abstract The neutron capture cross section of $$ ^{181} $$ 181 Ta is relevant to s-process of nuclear astrophysics, extraterrestrial samples analysis in planetary geology and new generation nuclear energy system design. The $$^{181}$$ 181 Ta( $$n,\gamma $$ n , γ ) cross section had been measured between 1 eV and 800 keV at the back-streaming white neutron facility (Back-n) of China spallation neutron source(CSNS) using the time-of-flight (TOF) technique and $$\hbox {C}_{6}\,\hbox {D}_{6}$$ C 6 D 6 liquid scintillator detectors. The experimental results are compared with the data of several evaluated libraries and previous experiments in the resolved and unresolved resonance region. Resonance parameters are extracted using the R-Matrix code SAMMY in the 1–700 eV region. The astrophysical Maxwell average cross section(MACS) from kT = 5 to 100 keV is calculated over a sufficiently wide range of neutron energies. For the characteristic thermal energy of an astrophysical site, at kT = 30keV the MACS value of $$^{181}$$ 181 Ta is 834 ± 75 mb, which shows an obvious discrepancy with the Karlsruhe Astrophysical Database of Nucleosynthesis in Stars (KADoNiS) recommended value 766 ± 15 mb. The new measurements strongly constrain the MACS of $$^{181}$$ 181 Ta( $$n,\gamma $$ n , γ ) reaction in the stellar s-process temperatures.

Abstract Early detection and appropriate medical treatment are of great use for ear disease. However, a new diagnostic strategy is necessary for the absence of experts and relatively low diagnostic accuracy, in which deep learning plays an important role. This paper puts forward a mechanic learning model which uses abundant otoscope image data gained in clinical cases to achieve an automatic diagnosis of ear diseases in real time. A total of 20,542 endoscopic images were employed to train nine common deep convolution neural networks. According to the characteristics of the eardrum and external auditory canal, eight kinds of ear diseases were classified, involving the majority of ear diseases, such as normal, Cholestestoma of the middle ear, Chronic suppurative otitis media, External auditory cana bleeding, Impacted cerumen, Otomycosis external, Secretory otitis media, Tympanic membrane calcification. After we evaluate these optimization schemes, two best performance models are selected to combine the ensemble classifiers with real-time automatic classification. Based on accuracy and training time, we choose a transferring learning model based on DensNet-BC169 and DensNet-BC1615, getting a result that each model has obvious improvement by using these two ensemble classifiers, and has an average accuracy of 95.59%. Considering the dependence of classifier performance on data size in transfer learning, we evaluate the high accuracy of the current model that can be attributed to large databases. Current studies are unparalleled regarding disease diversity and diagnostic precision. The real-time classifier trains the data under different acquisition conditions, which is suitable for real cases. According to this study, in the clinical case, the deep learning model is of great use in the early detection and remedy of ear diseases.

Abstract There is an increasing challenge to prevent illicit drug smuggling across borders and seaports. However, the existing techniques in-and-of-themselves are not sufficient to identify the illicit drugs rapidly and accurately. In the present study, combining nuclear resonance fluorescence (NRF) spectroscopy and the element (or isotope) ratio approach, we present a novel inspection method that can simultaneously reveal the elemental (or isotopic) composition of the illicit drugs, such as widely abused methamphetamine, cocaine, heroin, ketamine and morphine. In the NRF spectroscopy, the nuclei are excited by the induced photon beam, and measurement of the characteristic energies of the emitted $$\gamma $$ γ rays from the distinct energy levels in the excited nuclei provides “fingerprints” of the interested elements in the illicit drugs. The element ratio approach is further used to identify drug elemental composition in principle. Monte Carlo simulations show that four NRF peaks from the nuclei $$^{12}$$ 12 C, $$^{14}$$ 14 N and $$^{16}$$ 16 O can be detected with high significance of 7−24 $$\sigma $$ σ using an induced photon beam flux of $$10^{11}$$ 10 11 . The ratio of $$^{14}N$$ 14 N / $$^{12}C$$ 12 C and/or $$^{16}O$$ 16 O / $$^{12}C$$ 12 C for illicit drugs inspected are then extracted using the element ratio approach. It is found that the present results of simulations are in good agreement with the theoretical calculations. The feasibility to detect the illicit drugs, inside the 15-mm-thick iron shielding, or surrounded by thin benign materials, is also discussed. It is indicated that, using the state-of-the-art $$\gamma $$ γ -ray source of high intensity and energy-tunability, the proposed method has a great potential for identifying drugs and explosives in a realistic measurement time.

Abstract Nimesulide is an inhibitor of COX-2 with antioxidant and anti-inflammatory effects. However, few studies have explored the antidepressant mechanism of nimesulide. Here, we evaluated the therapeutic effects of nimesulide on CUMS rats. iTRAQ technology was used to identify the differentially expressed protein in the hippocampus between CUMS and nimesulide-treated rats to identify the possible molecular mechanism of its effects. We found that nimesulide had positive effects on depressive-like behaviors and inflammatory factors in depressed rats. Using proteomics technologies, we screened 16 differentially expressed proteins in CUMS-exposed rats after nimesulide treatment, 5 of which were related to inflammation. Overall, these results show that nimesulide might mediate its antidepressant effect on depressed rats through the inhibition of oxidative stress inflammatory response.

Abstract Ailanthus altissima (Mill.) Swingle and its variant A. altissima var. Qiantouchun are notorious invasive weeds. Two weevils, Eucryptorrhynchus scrobiculatus (ESC) and E. brandti (EBR) are considered as candidates for biological control of A. altissima. The aim of this study was to model the potential distributions of ESC and EBR using CLIMEX 4.0. The projected potential distributions of ESC and EBR included almost all current distribution areas of A. altissima, except Southeast Asia. Under historical climate, potential distribution area of EBR is larger than that of ESC, 46.67 × 106 km2 and 35.65 × 106 km2, respectively. For both ESC and EBR, climate change expanded the northern boundary of potential distributions northward approximately 600 km by the middle of 21st century, and 1000 km by the end of 21st century under RCP 8.5. However, the suitable range decreased to the south in the Southern Hemisphere because of heat stress. The modelled potential distributions of ESC and EBR in the United States demonstrated that the climate was suitable for both weevils. Therefore, considering only climate suitability, both ESC and EBR can be considered as potential biological control agents against A. altissima with some confidence that climatic conditions are likely suitable.

A layered nanostructure of a lead sulfide (PbS) quantum dot (QD)/multi-walled carbon nanotube (MWNT) hybrid was prepared by the electrostatic assembly after the phase transfer of PbS QDs from an organic to an aqueous phase. Well-crystallized PbS QDs with a narrow diameter (5.5 nm) was mono-dispersed on the sidewalls of MWNT by the electrostatic adsorption. Near-infrared absorption of PbS/MWNT nanostructures was improved and controlled by the packing density of PbS QDs. Efficient charge transfer between PbS and MWNT at the interface resulted in a remarkable quenching of photoluminescence up to 28.6% and a blue-shift of emission band by 300 nm. This feature was facilitated by band energy levels based on the intimate contact through the electrostatic interaction. Two-terminal devices using PbS/MWNT nanostructures showed an excellent on/off switching photocurrent and good stability during 20 cycles under light illumination due to electron transfer from PbS to MWNT. The photoswitch exhibited a high photo sensitivity up to 31.3% with the photocurrent of 18.3 μA under the light of 3.85 mW/cm2, which outperformed many QD/carbon-based nanocomposites. Results indicate that the electrostatic layered assembly of QD/MWNT nanostructure is an excellent platform for the fabrication of high-performance optoelectronic devices. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide-azobenzene (RGO-AZO) hybrids were prepared via covalent functionalization for long-term solar thermal storage. Thermal barrier (ΔEa) of cis to tran reversion and thermal storage (ΔH) were improved by molecular hydrogen bonds (H-bonds) through ortho- or para-substitution of AZO. Intramolecular H-bonds thermally stabilized cis-ortho-AZO on RGO with a long-term half-life of 5400 h (ΔEa 5 1.2 eV), which was much longer than that of RGO-para-AZO (116 h). RGO-para-AZO with one intermolecular H-bond showed a high density of thermal storage up to 269.8 kJ kg-1 compared with RGO-ortho-AZO (149.6 kJ kg-1) with multiple intra- and intermolecular H-bonds of AZO according to relaxed stable structures. Thermal storage in experiment was the same order magnitude to theoretical data based on ΔH calculated by density functional theory and packing density. Photoactive RGO-AZO hybrid can be developed for high-performance solar thermal storage by optimizing molecular H-bonds. [ABSTRACT FROM AUTHOR]

Abstract Demand for rapid and massive-scale exfoliation of bulky graphite remains high in graphene commercialization and property manipulation. We report a procedure utilizing “preformed acidic oxidizing medium (PAOM)” as a modified version of the Hummers’ method for fast and reliable synthesis of graphene oxide. Pre-mixing of KMnO4 and concentrated H2SO4 prior to the addition of graphite flakes enables the formation of effectively and efficiently oxidized graphene oxide (EEGO) featured by its high yields and suspension homogeneity. PAOM expedites diffusion of the Mn-oxidants into the graphite galleries, resulting in the rapid graphite oxidation, capable of oxidizing bulky graphite flakes (~0.8 mm in diameter) that can not be realized by the Hummers’ method. In the scale-up tests, ten-time amount of graphite can be completely exfoliated by PAOM without need of extended reaction time. The remarkable suspension homogeneity of EEGO can be exploited to deposit ultra-flat coating for wafer-scale nanopatterning. We successfully fabricated GO optical gratings with well-defined periodicity (300 nm) and uniform thickness (variation