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Abstract Under the condition that the working face was directly covered with hard roof, the abrupt breaking of hard roof release significant amount of energy, thus prone to triggering dynamic disasters such as roadway instability or rockburst. This paper based on the engineering background of the Xieqiao Coal Mine's 11,618 working face, a numerical simulation method was put forward to study the dynamic response of roadway under the disturbance of hard roof breaking and proposed an evaluation index I C for roadway stability. Research indicates that the elastic energy released during the periodic weighting of the hard roof is higher than that released during the first weighting. Under the dynamic disturbance caused by hard roof breaking, the peak stresses of the roadway was slight decreased, accompanied by a significant increase in the range of stress concentration and plastic zone expansion. Roadway deformation patterns are significantly influenced by hard roof breaking, with noticeable increases in deformation on the roof and right side. During the period of hard roof breaking, the possibility of instability of the roadway increase significantly due to the disturbance caused by the dynamic load. The research results reveal the instability mechanism of roadway under the condition of hard roof, and provide a more reliable basis for evaluating the stability of roadway.

The drilling identification technology of surrounding rock lithology can obtain the mechanical parameters of the surrounding rock of the roadway in real time, providing the basic guarantee for the surrounding rock support of the coal mine roadway. Based on the hydraulic anchor drilling rig for coal mine roadways, this paper developed the drilling parameter acquisition system of hydraulic anchor drilling rig in coal mine roadways, including the drilling system, power system, monitoring system and specimen platform. Drilling experiments of combined specimens of mortar of different strengths were carried out using this system. The experimental results indicate that the system shows good performance, obvious variation of the parameters with drilling, and obvious transitions of torque and propulsion pressure at the junction of different rock formations. In order to verify the feasibility of identifying rock strength while drilling, this study calculated the relationship between rock breaking specific energy by means of drilling parameters, and also analyzed the relationship between drilling parameters and compressive strength, it shows that based on the rock breaking specific energy method, the system can realize the identification of rock mechanical parameters by drilling parameters.

MicroRNAs (miRNAs) can participate in plant-insect interactions, which regulate plant defense networks. In this study, we analyzed the miRNA expression profiles of six rice varieties before and after brown planthopper (BPH)-feeding. We identified 45 differentially expressed miRNAs between BPH- susceptible and BPH-resistant rice varieties and 144 miRNAs that responded to BPH-feeding. Thus, miRNAs may be involved in multiple pathways regulating rice defense response against BPH. In addition, we found that the genetic history of rice varieties determined the regulation mode of the miRNA and affected the amounts, types, changing trends and response periods of miRNAs in response to BPH- feeding. To conclude, we scanned seven potential cross-kingdom miRNAs, of which miR5795 may target the vitellogenin gene in BPH, causing a 16.07% reduction in BPH oviposition. The results provide new miRNA information of rice-BPH interactions and BPH-resistant rice variety breeding.

C14H4O2S4, monoclinic, P21/n (no. 14), a = 3.85180(10) Å, b = 8.9728(2) Å, c = 18.0073(4) Å, β = 93.554(1)°, V = 621.16(3) Å3, Z = 2, R gt(F) = 0.0411, wR ref(F 2) = 0.1091, T = 301(2) K.

The (diphtheria, tetanus, and pertussis [acellular, component] [DTacP]) vaccine is a combined vaccine designed to prevent three potentially fatal diseases including pertussis, tetanus, and diphtheria in both children and adults. We utilized advanced technology to develop a novel DTacP vaccine that was previously unavailable in China. The nonclinical studies were performed to evaluate the immunogenicity, potential toxicity, and local tolerance of the vaccine in animal models. In the immunogenicity study, three batches of the vaccine were intraperitoneally administered to National Institutes of Health (NIH) mice, resulting in 100% seropositivity for all three batches. Additionally, antibody levels notably increased as the immunization dosage increased. In acute toxicity study, no mortality was observed among the animals during the 14‐day observation period, and no abnormalities in clinical signs were reported. Active systemic anaphylaxis assessment in guinea pigs showed no evidence of serious allergic reactions in the vaccine groups. In the repeat‐dose toxicity study, where five intramuscular doses were administered every 2 weeks, gross autopsy and histopathological examination revealed no vaccine‐related systemic pathological changes in rats, with dose site irritant reactions mostly recovered at the end of recovery period. In conclusion, the vaccine demonstrated good local and systemic tolerance, supporting its clinical development. We developed a novel DTacP vaccine that was previously unavailable in China and evaluated the immunogenicity, potential toxicity, and local tolerance of the vaccine in animal models. The seropositivity of vaccines reached 100% in mice. Acute toxicity study, active systemic anaphylaxis study, and repeat‐dose toxicity study showed no clinical signs abnormalities, and moderate irritant reactions were observed and mostly recovered at the end of recovery period. The DTacP vaccine demonstrated good local and systemic tolerance, supporting its clinical development. [ABSTRACT FROM AUTHOR]

Mutations in the non-structural protein regions of hepatitis C virus (HCV) are a cause of a non-sustained virological response (SVR) to treatment with direct-acting antivirals (DAAs) for chronic hepatitis; however, there are non-SVR cases without these mutations. In this study, we examined immune cell profiles in peripheral blood before and after ombitasvir/paritaprevir/ritonavir treatment and screened for genes that could be used to predict the therapeutic effects of DAAs. Fluorescence-activated cell sorting analysis indicated that the median frequencies of programmed cell death-1-positive (PD-1+) effector regulatory T cells (eTregs), PD-1+CD8+ T cells, and PD-1+Helper T cells were decreased significantly in SVR cases, but without significant changes in non-SVR cases. The frequency of PD-1+ naïve Tregs was significantly higher in the SVR group than in the non-SVR group before and after treatment. Similar results were found in patients treated with other DAAs (e.g., daclatasvir plus asunaprevir) and supported an immune response after HCV therapy. RNA-sequencing analysis indicated a significant increase in the expression of genes associated with the immune response in the SVR group, while genes related to intracellular and extracellular signal transduction were highly expressed in the non-SVR group. Therefore, we searched for genes associated with PD-1+ eTregs and CD8+ T cells that were significantly different between the SVR and non-SVR groups and found that T-box transcription factor 21 was associated with the non-SVR state. These results indicate that PD-1-related signaling pathways are associated with a non-SVR mechanism after DAAs treatment separate from mutation-related drug resistance. [ABSTRACT FROM AUTHOR]

Owing to the increasing need for green synthesis and environmental protection, the utilization of biological organism‐derived carbons as supports for noble‐metal electrocatalysts has garnered public interest. Nevertheless, the mechanism by which microorganisms generate nanometals has not been fully understood yet. In the present study, we used genetically engineered bacteria of Shewanella oneidensis MR‐1 (∆SO4317, ∆SO4320, ∆SO0618 and ∆SO3745) to explore the effect of surface substances including biofilm‐associated protein (bpfA), protein secreted by type I secretion systems (TISS) and type II secretion systems (T2SS), and lipopolysaccharide in microbial synthesis of metal nanoparticles. Results showed Pd/∆SO4317 (the catalyst prepared with the mutant ∆SO4317) shows better performance than other biocatalysts and commercial Pd/C, where the mass activity (MA) and specific activity (SA) of Pd/∆SO4317 are 3.1 and 2.1 times higher than those of commercial Pd/C, reaching 257.49 A g−1 and 6.85 A m−2 respectively. It has been found that the exceptional performance is attributed to the smallest particle size and the presence of abundant functional groups. Additionally, the absence of biofilms has been identified as a crucial factor in the formation of high‐quality bio‐Pd. Because the absence of biofilm can minimize metal agglomeration, resulting in uniform particle size dispersion. These findings provide valuable mechanical insights into the generation of biogenic metal nanoparticles and show potential industrial and environmental applications, especially in accelerating oxygen reduction reactions. [ABSTRACT FROM AUTHOR]

With its early start in urbanization, Europe has accumulated a wealth of practical experience in urban agriculture (UA), exploring various development models. This paper compares and analyzes the characteristic patterns of UA in Europe and China through theoretical research, academic frontier exploration, and case analysis. In order to investigate and analyze theoretical developments and the current state of academic frontiers in a systematic, accessible, and comprehensive approach, the methodology of bibliometric analysis has been utilized. A bibliometric method is applied to analyze relevant data from the Web of Science (WoS) core collection database and 2230 CNKI publications. The case study section conducts separate field research on nine representative European practices of urban food gardening and urban farming. Additionally, the study scrutinizes UA research development and its implementation in Hangzhou, China. Based on the findings of this study, the authors recommend that European approaches to the development of UA in China's future UA practice be taken into account, in particular their methods and strategies for realizing social and cultural benefits. It is imperative to integrate UA projects into urban green space system planning and to rationalize their construction types. Simultaneously, Chinese scholars are encouraged to explore the socio-cultural functions of UA, with a particular focus on urban agricultural heritage conservation. [ABSTRACT FROM AUTHOR]

The development of efficient catalysts for proton exchange membrane fuel cells (PEMFCs) is crucial for their commercial viability. This study introduces a method for synthesizing Pd nanoparticles on carbon supports as electrocatalysts using microbial synthesis, specifically employing the bacterium Shewanella oneidensis MR-1. The so-produced catalysts exhibit enhanced catalytic activity and stability for the oxygen reduction reaction (ORR). The microbial synthesis approach offers advantages, such as high purity, cost-effectiveness, and environmental friendliness. Additionally, the use of sodium alginate (SA) hydrogel in the synthesis process further improves the catalyst's performance due to its metal chelating properties. The resulting Pd/C electrocatalysts, especially those synthesized with a composite matrix of SA and CaCO3, demonstrate superior ORR performances outperforming that of commercial Pd/C catalysts. It was found that the composite substrate affected the palladium recovery rate, whose increasing palladium absorption, refined particle size, improved graphitization degree, and increasing pyridinic-N of the resultant catalyst synergistically enhanced the availability of active centers that eventually contributed to the superior ORR performances. This research paves the way for the development of high-performance and cost-effective catalysts for PEMFCs. [ABSTRACT FROM AUTHOR]

Background: Precise regulation of partial critical proteins in cancer cells, such as anti‐apoptotic proteins, is one of the crucial strategies for treating cancer and discovering related molecular mechanisms. Still, it is also challenging in actual research and practice. The widely used CRISPR/Cas9‐based gene editing technology and proteolysis‐targeting chimeras (PROTACs) have played an essential role in regulating gene expression and protein function in cells. However, the accuracy and controllability of their targeting remain necessary. Methods: Construction of UMUC‐3‐EGFP stable transgenic cell lines using the Sleeping Beauty system, Flow cytometry, quantitative real‐time PCR, western blot, fluorescence microplate reader and fluorescence inverted microscope analysis of EGFP intensity. Characterization of Survivin inhibition was done by using Annexin V‐FITC/PI apoptosis, calcein/PI/DAPI cell viability/cytotoxicity assay, cloning formation assay and scratch assay. The cell‐derived xenograft (CDX) model was constructed to assess the in vivo effects of reducing Survivin expression. Results: Herein, we established a synergistic control platform that coordinated photoactivatable split‐Cas9 targeted gene editing and light‐induced protein degradation, on which the Survivin gene in the nucleus was controllably edited by blue light irradiation (named paCas9‐Survivin) and simultaneously the Survivin protein in the cytoplasm was degraded precisely by a nanobody‐mediated target (named paProtacL‐Survivin). Meanwhile, in vitro experiments demonstrated that reducing Survivin expression could effectively promote apoptosis and decrease the proliferation and migration of bladder cancerous cells. Furthermore, the CDX model was constructed using UMUC‐3 cell lines, results from animal studies indicated that both the paCas9‐Survivin system and paProtacL‐Survivin significantly inhibited tumour growth, with higher inhibition rates when combined. Conclusions: In short, the coordinated regulatory strategies and combinable technology platforms offer clear advantages in controllability and targeting, as well as an excellent reference value and universal applicability in controlling the fate of cancer cells through multi‐level regulation of key intracellular factors. [ABSTRACT FROM AUTHOR]

The progress of commercial VR headsets largely depends on the progress of sensor technology, the iteration of which often means longer research and development cycles, and also higher costs. With the continuous maturity and increasing competition of VR headsets, designers need to create a balance among user needs, technologies, and costs to achieve commercial competition advantages. To make accurate judgments, consumer feedback and opinions are particularly important. Due to the increasing maturity in the technology of commercial VR headsets in recent years, the cost has been continuously decreasing, and potential consumers have gradually increased. With the increase in consumer demand for virtual reality headsets, it is particularly important to establish a perceptual quality evaluation system. The relationship between consumer perception and product quality determined by evaluations of experience is improving. Using the research method implemented in this work, through semi-structured interviews and big data analysis of VR headset consumption, the perceptual quality elements of VR headsets are proposed, and the order of importance of perceptual quality attributes is determined by questionnaire surveys, quantitative analysis, and verification. In this study, the perceptual quality elements, including technical perceptual quality (TPQ) and value perceptual quality (VPQ), of 14 types of VR headsets were obtained, and the importance ranking of the VR headsets' perceptual quality attributes was constructed. In theory, this study enriches the research on VR headsets. In practice, this study provides better guidance and suggestions for designing and producing VR headsets so that producers can better understand which sensor technology has met the needs of consumers, and which sensor technology still has room for improvement. [ABSTRACT FROM AUTHOR]

The superlarge Huaaobaote Ag–Pb–Zn deposit is located on the western slope of the southern Great Xing'an Range (SGXR). The deposit includes four ore blocks, namely, ore blocks I, II, III, and V. Except for the no. I orebody of ore block I, which is hosted in the contact zone between the Carboniferous serpentinized harzburgite and the Permian siltstone, the other orebodies all occur as veins controlled by faults. The mineralization process at the deposit can be divided into four stages: cassiterite–arsenopyrite–pyrite–quartz stage (stage I), cassiterite–chalcopyrite–pyrite–freibergite–arsenopyrite–pyrrhotite–quartz stage (stage II), sphalerite–galena–jamesonite–stibnite–freibergite–silver mineral–quartz–calcite–chlorite stage (stage III), and argentite–pyrargyrite–pyrite–quartz–calcite (stage IV). Cassiterite U–Pb dating of the Huaaobaote deposit yielded ages of 136.3–134.3 Ma, indicating that the deposit formed in the Early Cretaceous period. Two types of fluid inclusions (FIs), including liquid-rich and gas-rich FIs, have been distinguished in the quartz vein and sphalerite. The homogenization temperature during the four stages gradually decreases, with temperatures of 302–340 °C for stage I, 267–304 °C for stage II, 186–273 °C for stage III, and 166–199 °C for stage IV, respectively. The salinity (wt% NaCl eqv.) at stages I, II, III, and IV is 3.7–6.6, 0.2–4.5, 0.2–5.0, and 0.4–1.6, respectively, indicating that the ore-forming fluid is characterized by low salinity. The δ18Owater and δD values of the ore-forming fluid range from −11.9‰ to 7.9‰ and −168‰ to −76‰, respectively, indicating that the ore-forming fluid was dominantly derived from a mixture of magmatic and meteoric water. The calculated δ34SH2S values range from −3.6‰ to 1.2‰, indicating that the sulfur mainly came from granitic magma. The 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb ratios of sulfides are in the ranges of 18.195–18.317, 15.509–15.667, and 37.965–38.475, respectively, implying that the ore-forming material was mainly derived from felsic magma that may be formed by the partial melting of orogenic materials. Fluid mixing, cooling, and immiscibility were the three primary mechanisms for mineral precipitation in the Huaaobaote deposit. [ABSTRACT FROM AUTHOR]