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In the process of mining, a large area of hard roof will be exposed above a goaf and may suddenly break. This can easily induce rock burst and has a significant impact on production safety. In this study, based on the engineering background of the hard roof of the 2102 working face in the Balasu coal mine, the spatial and temporal characteristics of the strain energy of the roof during the initial mining process were explored in depth. Based on a theoretical calculation, it is proposed that hydraulic fracturing should be carried out in the medium-grained sandstone layer that is 4.8–22.43 m above the roof, and that the effective fracturing section in the horizontal direction should be within 30.8 m of the cutting hole of the working face. The elastic strain energy fish model was established in FLAC3D to analyze the strain energy accumulation of the roof during the initial mining process. The simulation and elastic strain energy results show that, as the working face advances to 70–80 m, the hard roof undergoes significant bending deformation. The energy gradient increases with the rapid accumulation of strain energy to a peak value of 140.54 kJ/m3. If the first weighting occurs at this moment in time, the sudden fracture of the roof will be accompanied by the release of elastic energy, which will induce rock burst. Therefore, it is necessary to implement roof cutting and pressure relief before reaching the critical step of 77 m. To this end, the comprehensive hydraulic fracturing technology of ‘conventional short drilling + directional long drilling’ is proposed. A field test shows that the hydraulic fracturing technology effectively weakens the integrity of the rock layer. The first weighting interval is 55 m, and it continues until the end of the pressure at the 70 m position. The roof collapses well, and the mining safety is improved. This study provides an important reference for hard roof control.

[Objective] The village type identification was carried out scientifically to provide technical support and a decision-making reference for the formulation of the overall territorial space planning and the implementation of the rural revitalization strategy for Xingguo County, Jiangxi Province, in order to provide experience reference for the village type identification in the hills and mountains in Southern China. [Methods] Villages were taken as the research units. A village layout suitability evaluation index system and a rural revitalization potential evaluation index system were constructed. The village types in Xingguo County were identified by combining the AHP and CRITIC methods to determine the index weight. A coupling coordination model was constructed. [Results] ① The overall village layout suitability in Xingguo County was in the general level, and the suitability grades were mainly in the middle suitability level, with significant differences in spatial distribution, showing the spatial characteristics of "decreasing in a stepwise manner from the central part of the city to the surrounding areas" . ② The overall level of rural revitalization potential needs to be improved. The high-level areas were mainly located in the villages surrounding the urban areas and the resident villages of each township. ③ The coupling degree between the suitability of village layout and rural revitalization was high. The coordination degree needs to be improved from the average coupling coordination degree, with the largest number of villages at the primary coupling coordination degree. ④ The types of villages in Xingguo County were identified as suburban integration villages, clustered development villages, survival and upgrading villages, characteristic protection villages, and relocated and evacuated villages. Corresponding development strategies were proposed for different types of villages. [Conclusion] Village layout was closely related to local topography and social and economic development. The potential of rural revitalization was positively correlated with the suitability of rural layout. Therefore, different development strategies should be proposed for different village types.

Abstract Purpose This single-arm, prospective, exploratory study investigated the effectiveness of ultra-low-dose radiotherapy in the treatment of ocular adnexal lymphoma (OAL). Patients and methods Patients with pathologically confirmed ocular adnexal low-grade non-Hodgkin lymphoma (predominantly mucosa-associated lymphoid tissue, MALT or follicular lymphoma) were included and treated with ultra-low-dose radiotherapy consisting of 2 successive fractions of 2 Gy at our institution between 2019 and 2021. Disease response was assessed clinically and radiographically within 4 months and at 3 to 6-month intervals after treatment. Data collected included rates of overall response, complete response (CR), partial response (PR), lesion size, and acute/chronic ocular toxic effects. Results Sixteen patients with median age of 63 years (range 23–86 years) were included in the study. The histological subtypes included MALT (11 patients; 69%); follicular lymphoma (2 patients; 12%); Lymphoid hyperplasia (3 patient, 19%). At a median follow-up time of 15.5 months (range 5.0–30.0 months), the overall response rate was 88%, with a CR rate of 75% (n = 12) and a PR rate of 13% (n = 2). The average lesion area was reduced from 117.9 ± 60.4 mm2 before radiation therapy to 38.7 ± 46.0mm2 at initial evaluation post radiation therapy (P = 0.002, n = 16), and to 8.5 ± 21.2 mm2 (P

Uncontrolled hemorrhage caused by trauma can easily lead to death. Efficient and safe hemostatic materials are an urgent and increasing need for hemostatic research. Following a trauma, wound healing is induced by various cellular mechanisms and proteins. Hemostatic biomaterials that can not only halt bleeding quickly but also provide an environment to promote wound healing have been the focus of research in recent years. Mussel-inspired nanoparticle composite hydrogels have been propelling the development of hemostatic materials owing to their unique advantages in adhesion, hemostasis, and bacteriostasis. This review summarizes the hemostatic and antimicrobial fundamentals of polydopamine (PDA)-based nanomaterials and emphasizes current developments in hemorrhage-related PDA nanomaterials. Moreover, it briefly discusses safety concerns and clinical application problems with PDA hemostatic nanomaterials.

Abstract Ultrafine hollow nanoparticles‐based (7 nm) carbon nanoclusters (HNPCNCs) are developed by a facile and novel method. Benefiting from the ultrafine nanostructure, we have achieved close‐packed storage of K metallic clusters and a close‐packed K metallic clusters with a diameter of 7 nm has been observed for the first time through ex TEM. In K‐ion batteries, HNPCNCs anodes deliver an ultrahigh capacity of 269.8 mA h g−1 at 0.5 A g−1 after 200 cycles, outstanding rate performance of 150.5 mA h g−1 after 5000 cycles at 5 A g−1. Moreover, an excellent electrochemical performance has been obtained by HNPCNCs//potassium Prussian blue potassium‐ion full cells, highlighting the practicability of HNPCNCs. The unprecedented electrochemical performance is attributed to the close‐packed K metallic clusters achieved by unique ultrafine hollow nanoparticles in the carbon nanoclusters.

Abstract A facile strategy to fabricate gold nanorod@polyacrylic acid/calcium phosphate (AuNR@PAA/CaP) yolk–shell nanoparticles (NPs) composed with a PAA/CaP shell and an AuNR yolk is reported. The as-obtained AuNR@PAA/CaP yolk–shell NPs possess ultrahigh doxorubicin (DOX) loading capability (1 mg DOX/mg NPs), superior photothermal conversion property (26%) and pH/near-infrared (NIR) dual-responsive drug delivery performance. The released DOX continuously increased due to the damage of the CaP shell at low pH values. When the DOX-loaded AuNR@PAA/CaP yolk–shell NPs were exposed to NIR irradiation, a burst-like drug release occurs owing to the heat produced by the AuNRs. Furthermore, AuNR@PAA/CaP yolk–shell NPs are successfully employed for synergic dual-mode X-ray computed tomography/photoacoustic imaging and chemo-photothermal cancer therapy. Therefore, this work brings new insights for the synthesis of multifunctional nanomaterials and extends theranostic applications.

Bistatic scattering coefficient have important application of ocean active microwave remote sensing. In this paper, a general expression of the composite scattering coefficient for multiple dielectric targets of one-dimensional fractal sea surface is derived by MOM method. Secondly, the bistatic scattering coefficient is computed, there are two class missile targets and one class ship target of one-dimensional fractal sea surface, and the influence of the water dielectric constant, fractal dimension, wind speed, the target dielectric constant and spatial position is discussed, and the corresponding conclusions are given. The proposed algorithm is able to solve some composite scattering problems, such as 'dielectric or conductive object + rough surface', 'dielectric or conductive floating object +rough' and it has certain generalization and reference, and it lays a foundation for solving the composite scattering coefficient of multiple medium targets in two-dimensional fractal sea surface. [ABSTRACT FROM AUTHOR]

A facile strategy to fabricate gold nanorod@polyacrylic acid/calcium phosphate (AuNR@- PAA/CaP) yolk-shell nanoparticles (NPs) composed with a PAA/CaP shell and an AuNR yolk is reported. The asobtained AuNR@PAA/CaP yolk-shell NPs possess ultrahigh doxorubicin (DOX) loading capability (1 mg DOX/mg NPs), superior photothermal conversion property (26%) and pH/near-infrared (NIR) dual-responsive drug delivery performance. The released DOX continuously increased due to the damage of the CaP shell at low pH values. When the DOX-loaded AuNR@PAA/CaP yolk-shell NPs were exposed to NIR irradiation, a burst-like drug release occurs owing to the heat produced by the AuNRs. Furthermore, AuNR@PAA/CaP yolk-shell NPs are successfully employed for synergic dual-mode X-ray computed tomography/photoacoustic imaging and chemo-photothermal cancer therapy. Therefore, this work brings new insights for the synthesis of multifunctional nanomaterials and extends theranostic applications. [ABSTRACT FROM AUTHOR]

This paper presents experimental research and finite element analysis (FEA) on a new type of frame wall that has fiber cement pressure (FCP) panel as sheathing. Some new structural details for the connection and energy conservation are proposed. In order to evaluate the bending capacity of the FCP frame wall, eight specimens with the parameters of stud spacing, connection styles, window opening, and loading sides were tested under uniformly distributed loads. The measurements of each material property were taken before the bending tests. Failure modes, load-deformation curves, and the strain of some key points were all obtained. The results indicate that the designed parameters affected the ultimate bearing capacity and failure mode of the specimens. Moreover, a non-linear FE model was made and verified against the tests. Results of FEA agree well with the experiment in failure modes and load-deformation curves. Therefore, FEA was confirmed as reliable for the prediction of the loading process. Finally, extended parametric analysis of FCP frame wall was conducted. [ABSTRACT FROM AUTHOR]

Objective: To investigate the stroke risk and risk factors in patients with chronic schizophrenia. Patients and methods: This study was a large-sample, cross-sectional survey. A total of 363 patients with chronic schizophrenia were selected from the Changping Traditional Chinese Medicine Hospital, Beijing, in August 2014. The patients were divided into either stroke group or control group based on the presence of stroke. Clinical evaluation included positive and negative syndrome scale assessment and a detailed questionnaire to collect the general information and disease-related conditions. Results: The prevalence of stroke was 16.5% (60 cases). Stroke and control groups showed a significant difference in age, sex, smoking, combined medication, doses, negative factor score in positive and negative syndrome scale, body mass index, waist circumference, and systolic blood pressure. Multivariate analysis showed that a number of factors are significantly related to stroke, including age, sex, smoking, combined medication, doses, body mass index, and systolic blood pressure. Conclusion: The prevalence of stroke is relatively higher in Chinese patients with chronic schizophrenia. Chronic schizophrenia patients are more likely to suffer from stroke; meanwhile, a number of risk factors were identified, including old age, female sex, smoking history, combined medication with a variety of drugs, high doses, obesity, and high blood pressure. [ABSTRACT FROM AUTHOR]

In order to study the influence of web holes on axial compression behaviors of thin-walled columns with different section forms, a total of 10 pin-ended compression specimens with two section forms were tested. One section is channels with complex edge stiffeners and web holes, the other section is channels with complex edge stiffeners and Σ type web stiffeners and web holes. The ultimate load, buckling mode and deformation behavior of these specimens were studied. It was found that the axial compression loading efficiency of perforated Σ-section specimens can increase about 30% to 50%, which compared with channels with complex edge stiffeners and web holes under the same conditions. The tests were simulated by finite element analysis (FEA), and the analysis results agreed well with experimental data. It was shown that the loading efficiency of Σ-section models with holes decreased about 25% compared with the same section models without holes. While channel section models with complex edge stiffeners and holes decreased about 6% average. Furthermore, the direct strength method (DSM) was used to calculate the ultimate loading capacity of perforated channels with complex edge stiffeners. The results indicate that the existing DSM formulas for perforated members, developed mainly based on channel sections with simple edge stiffeners, are also valid for channels with complex edge stiffeners and web holes under axial compression. [ABSTRACT FROM AUTHOR]

A facile two-step strategy was developed to fabricate yellow fluorescent glutathione-Au nanoclusters/zeolitic imidazolate framework-8 nanoparticles (GSH-Au NCs/ZIF-8 NPs) and their derived Au/ZnO NPs, which exhibited visible light photocatalytic hydrogen evolution together with degradation of Rhodamine B (RhB). [ABSTRACT FROM AUTHOR]

A universal method was utilized to fabricate rhombic dodecahedral zeolitic imidazolate framework-8@SiO2 (ZIF-8@SiO2) nanoparticles (NPs) and their derivatives, ZnO@SiO2, ZIF-8@SiO2 yolk--shell and SiO2 hollow NPs, using ZIF-8 NPs as the template. [ABSTRACT FROM AUTHOR]

Rapid and sensitive detection of 2,4,6-trinitrotoluene (TNT) and 4-nitrophenol (4-NP) has attracted considerable attention due to their wide applications as nitroaromatic explosive materials. A novel fluorescence method for TNT and 4-NP based on bovine serum albumin functionalized fluorescent gold nanoclusters (BSA Au-NCs) has been developed. The detection probe BSA Au-NCs can be used as a fluorescent probe for the sensitive and selective detection of TNT and 4-NP simultaneously. A good linearity of fluorescence detection using BSA Au-NCs as a fluorescent probe was observed for TNT and 4-NP concentrations in the range of 10-8-5 × 10-5 M and 10-9-5 × 10-5 M, with a detection limit of 10 nM and 1 nM, respectively. The high specificity of TNT and 4-NP with BSA Au-NCs interactions provided excellent selectivity towards detecting TNT and 4-NP over other relevant nitroaromatic compounds. This system can be applied to test strips to detect TNT and 4-NP with high sensitivity and selectivity. The vapour of TNT and 4-NP can be detected using BSA Au-NCs test paper within 1 min with a detection limit of 10 pM and 1 pM. [ABSTRACT FROM AUTHOR]

The article discusses the facile two-step approach for the fabrication of green fluorescent carbon nanodots@zeolitic imidazolate framework-8 nanoparticles (C-dots@ZIF-8 NP) with tunable size and fluorescence intensity. The nanoparticles serve as platforms for simultaneous pH-responsive drug delivery and fluorescence imaging for cancer cells. It also compares the c-dots against toxic metal-based quantum dots (QD).

A method based on use of functionalized gold nanoparticles on polyethylenimine film has been developed for colorimetric detection of immunoglobulin G (IgG). The immunogold nanoparticles were immobilized on quartz slides by recognition between antibody and antigen, with the antigen chemically adsorbed on the polyethylenimine film. By measurement of the UV–visible spectra of the immobilized immunogold, detection of h-IgG was achieved. The detection limit for h-IgG by use of this method can be as low as 0.01 μg mL−1. This method is quite promising for numerous applications in immunoassay. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A simple, cost-effective yet rapid and sensitive colorimetric sensor for the detection of Hg2+ using L-cysteine functionalized gold nanoparticles induced by ultraviolet radiation was developed. The sensitivity and selectivity of detection was also investigated. The L-cysteine modified gold nanoparticles can be induced to aggregate quickly in the presence of Hg2+, especially with the assistance of ultraviolet radiation. The presence of Hg2+ can be monitored by the colorimetric response of gold nanoparticles. The detection of Hg2+ could be realized, after measuring the UV-vis spectra, with a detection limit of 100 nM. The selectivity of this method has been investigated by other divalent metal ions. The effective colorimetric sensor can be used for on-site and real-time Hg2+ detection. [ABSTRACT FROM AUTHOR]

A one-step rapid and ultrasensitive immunoassay capable of detecting proteins in blood serum is developed using gold nanoprobes and fluorescence correlation spectroscopy (FCS). In this approach we take advantage of the inherent photoluminescence property of gold nanoparticles (GNPs) to develop a fluorophore-free assay to observe binding entities by monitoring the diffusion of bound versus unbound molecules in a limited confocal volume. 40-nmGNPs conjugated separately with rabbit anti-IgG (Fc) and goat anti-IgG (Fab) when incubated in blood serum containing IgG forms a sandwich structure constituting dimers and oligomers that can be differentiated by to detect IgG in blood serum at a limit of detection (LOD) of 5 pgml. The novelty of integrating GNPs with FCS to develop a sensitive blood immunoassay brings single molecule methods one step closer to the clinic. [ABSTRACT FROM AUTHOR]

This paper reports for the first time that the shape of silver nanostructures on quartz slides, from a nanoprism to a nanodisc, can be easily realized within a few minutes simply by adjusting the pH value of the immersion solution. Different colours of the quartz slide covered with Ag nanostructures appeared, from deep blue to yellow, corresponding to the shapes of Ag nanostructures changing from nanoprisms to nanodiscs. Surface-enhanced Raman scattering (SERS) activities of the silver nanoprisms and nanodiscs (obtained through adjusting the pH values) were checked using p-aminothiophenol (p-ATP) as a probe molecule at both near-infrared (1064 nm) and visible light (514.5 nm) excitation. The results obtained further confirmed the enhancement mechanism of SERS based on the coupling between the surface plasmon resonance (SPR) of the substrates and the laser excitation wavelength. This work will be of great significance in understanding the SERS enhancement mechanism and in the fabrication of nanoparticle films for biosensing. [ABSTRACT FROM AUTHOR]