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Familial hypercholesterolemia (FH) is an inherited disorder of lipid metabolism characterized by significant elevation of low-density lipoprotein cholesterol, increasing the risk of atherosclerotic cardiovascular disease and causing serious consequences for FH patients and the whole society. The development of molecular biotechnology is crucial for screening, diagnosing, and treating patients with FH. This paper systematically summarizes how the development of genetic testing technologies, particularly next-generation sequencing, has improved the accuracy of diagnosis and efficiency of genetic screening for FH, while also introducing many variations of unknown significance. In contrast to pharmacotherapy, transgenic technology and gene editing technology offer the potential to rectify the molecular aberration within the patient's physiological system, holding promise for eradicating FH at the molecular level. However, preliminary results have shown that patients could suffer from side-effects, such as liver damage, and long-term follow-up is needed to clarify the efficacy of these technologies. Therefore, this article reviews the latest advances in molecular biotechnology, including genetic testing technology and gene therapy technology, in the diagnosis and treatment of FH, aiming to provide new perspectives for FH related research.

Island is a special area with natural and socio-economic vulnerability, which to some extent restricts the livelihood strategy choices and development of island residents. Relying on the rich tourism resources of the island, the tourism industry has become an important source of livelihood for farmers in the villages around the scenic spots in the island. However, The difference of tourism resource endowment of different villages will inevitably affect the livelihood capital level of farmers in different villages. This paper takes 15 villages of South Changshan Island and North Changshan Island of Changdao as the research area, constructs the livelihood capital evaluation index system, measures the total livelihood capital index of Yujiale farmers in the research area, analyzes the spatial distribution pattern and agglomeration characteristics of the total livelihood capital index, and put forward suggestions to improve the livelihood capital level of Yujiale farmers to promote the sustainable livelihood development of island farmers.

Pyroptosis induced by oxidative stress is a significant contributor to mental health disorders, including depression (+)-Catechin (CA), a polyphenolic compound prevalent in various food sources, has been substantiated by prior research to exhibit potent antioxidant properties and potential antidepressant effects. Nonetheless, the precise antidepressive mechanisms and effects of CA remain incompletely elucidated. In this study, we employed corticosterone (CORT) and PC12 cells to develop a cellular model of depression, aiming to investigate the protective effects of CA against CORT-induced cellular damage. Our objective was to elucidate the underlying mechanisms of protective action. We utilized transcriptomic analysis to identify differentially expressed genes and employed bioinformatics approaches to predict the potential mechanisms of CA’s protective effects in PC12 cells. These transcriptomic predictions were subsequently validated through western blot analysis. The findings indicated that CA possesses the capacity to mitigate oxidative stress and suppress pyroptosis in PC12 cells via the activation of the PI3K/AKT signaling pathway. This activation subsequently modulates the Nrf2/HO1/NF-κB pathways, thereby providing protection to PC12 cells against damage induced by CORT. Furthermore, we investigated the interaction between CA and the Keap1 protein employing molecular docking and protein thermal shift assays. We propose that CA can activate Nrf2 through two mechanisms to decrease reactive oxygen species (ROS) levels and inhibit pyroptosis: one mechanism involves the activation of the PI3K/AKT signaling pathway, and the other involves direct binding to Keap1, leading to an increase in p-Nrf2.

SignificanceCrop production is related to national food security, economic development and social stability, so timely information on the growth of major crops is of great significance for strengthening the crop production management and ensuring food security. The traditional crop growth monitoring mainly judges the growth of crops by manually observing the shape, color and other appearance characteristics of crops through the external industry, which has better reliability and authenticity, but it will consume a lot of manpower, is inefficient and difficult to carry out monitoring of a large area. With the development of space technology, satellite remote sensing technology provides an opportunity for large area crop growth monitoring. However, the acquisition of optical remote sensing data is often limited by the weather during the peak crop growth season when rain and heat coincide. Synthetic aperture radar (SAR) compensates well for the shortcomings of optical remote sensing, and has a wide demand and great potential for application in crop growth monitoring. However, the current research on crop growth monitoring using SAR data is still relatively small and lacks systematic sorting and summarization. In this paper, the research progress of SAR inversion of crop growth parameters were summarized through comprehensive analysis of existing literature, clarify the main technical methods and application of SAR monitoring of crop growth, and explore the existing problems and look forward to its future research direction.Progress]The current research status of SAR crop growth monitoring were reviewed, the application of SAR technology had gone through several development stages: from the early single-polarization, single-band stage, gradually evolving to the mid-term multi-polarization, multi-band stage, and then to the stage of joint application of tight polarization and optical remote sensing. Then, the research progress and milestone achievements of crop growth monitoring based on SAR data were summarized in three aspects, namely, crop growth SAR remote sensing monitoring indexes, crop growth SAR remote sensing monitoring data and crop growth SAR remote sensing monitoring methods. First, the key parameters of crop growth were summarized, and the crop growth monitoring indexes were divided into morphological indicators, physiological and biochemical indicators, yield indicators and stress indicators. Secondly, the core principle of SAR monitoring of crop growth parameters was introduced, which was based on the interaction between SAR signals and vegetation, and then the specific scattering model and inversion algorithm were used to estimate the crop growth parameters. Then, a detailed summary and analysis of the radar indicators mainly applied to crop growth monitoring were also presented. Finally, SAR remote sensing methods for crop growth monitoring, including mechanistic modeling, empirical modeling, semi-empirical modeling, direct monitoring, and assimilation monitoring of crop growth models, were described, and their applicability and applications in growth monitoring were analyzed.Conclusions and ProspectsFour challenges exist in SAR crop growth monitoring are proposed: 1) Compared with the methods of crop growth monitoring using optical remote sensing data, the methods of crop growth monitoring using SAR data are obviously relatively small. The reason may be that SAR remote sensing itself has some inherent shortcomings; 2) Insufficient mining of microwave scattering characteristics, at present, a large number of studies have applied the backward scattering intensity and polarization characteristics to crop growth monitoring, but few have applied the phase information to crop growth monitoring, especially the application study of polarization decomposition parameters to growth monitoring. The research on the application of polarization decomposition parameter to crop growth monitoring is still to be deepened; 3) Compared with the optical vegetation index, the radar vegetation index applied to crop growth monitoring is relatively less; 4 ) Crop growth monitoring based on SAR scattered intensity is mainly based on an empirical model, which is difficult to be extended to different regions and types of crops, and the existence of this limitation prevents the SAR scattering intensity-based technology from effectively realizing its potential in crop growth monitoring. Finally, future research should focus on mining microwave scattering features, utilizing SAR polarization decomposition parameters, developing and optimizing radar vegetation indices, and deepening scattering models for crop growth monitoring.

The 6061 aluminum alloy was prepared by powder metallurgy method, and the effects of ball milling time and solution-aging treatment on microstructure and mechanical properties of the extruded alloy were studied by means of optical microscopy, scanning electron microscopy, transmission electron microscopy, hardness test and tensile test, etc. The results show that with the prolongation of the ball milling time, the powder morphology gradually changes from spherical to flat sheet, and the powder particle size gradually increases. The sintered alloy has better density and comprehensive mechanical properties when milling for 2 h, but longer milling time will lead to the decrease of density and mechanical properties of the material. The better solution-aging process of sintered alloy after hot extrusion is 530 ℃×1 h+180 ℃×8 h, at which time the alloy precipitates a diffuse distribution and a fine β″ phase, and the alloy has high strength (442 MPa) and hardness (125HV), as well as suitable elongation. Its excellent mechanical properties are mainly the result of the combination of dispersion strengthening, fine grain strengthening and solid solution strengthening.

Objective To analyze the clinical characteristics of thyroid LCH to enhance understanding of the disease. Methods We retrospectively studied the clinical data from six thyroid LCH patients who hospitalized in Huashan Hospital Affiliated to Fudan University from January 2015 to January 2022.We analyzed the ultrasound and 18F FDG-PET/CT imaging characteristics of thyroid LCH. Results The six patients diagnosed (2 males and 4 females) were between 18 and 58 years old.All patients had diabetes insipidus.MRI revealed thickened pituitary stalk.Two cases had central hypothyroidism, while four cases euthyroidism.Three cases tested positive for thyroid antibodies.Ultrasound showed thyroid nodules of TI-RADS 3 in three cases, TI-RADS 4 in two cases, and 1 with nodular goiter.Ultrasound showed that all sic cases indicated low echogenicity, 5 of which clear boundaries, 4 of which uneven echo distribution, 5 of which irregular shape, and noen has calcification.18F FDG-PET/CT indicated high uptake nodules with SUVmax values all above 10.4 cases were diagnosed by surgical excision and the other 2 by coarse-needle aspiration biopsy.When diagnosed, two cases had liver and thymus involvement respectively.One case had lung and bone involvement respectively.After treatment, 4 cases showed that nodular goiter shrank, while the other two with liver involvement progressed fast and no assessment made. Conclusions Thyroid LCH presented low echogenicity, clear boundaries, irregular shape, without calcification, and high uptake in 18F FDG-PET/CT.A definite diagnosis of pituitary stalk thicking accompanied by thyroid nodules, especially those with hypoechoic and irregular nodules, can be achieved by coarse-needle aspiration biopsy and langerin-specific pathological staining.

Background As the prevalence of hypertension in China's rural areas is very high, hypertension management in these areas is particularly important. Objective To summarize the characteristics and weaknesses of hypertension management in Shandong's rural areas using the Innovative Care for Chronic Conditions Framework (ICCC) proposed by the WHO, and to put forward targeted recommendations. Methods According to the socio-economic level and geographical distribution of hypertension prevalence, three county-level centers for disease control and prevention, 9 town health centers and 36 village clinics were selected from A county of Heze, B district of Jinan and C city of Weihai in Shandong Province, from which 84 cases (including individuals responsible for hypertension management programs, medical workers and hypertensive patients) were selected from June to July 2021 using a purposive sampling method to attend a face-to-face semi-structured interview for understanding the status of hypertension management in Shandong's rural areas. NVivo 12 and Qualitative Data Analysis Model proposed by MILES and HUBERMAN, were used to encode and analyse the interview results using the macro-, meso- and micro-level components of the ICCC. Results A total of 13 themes and 51 subthemes were derived from the analysis at three levels. At the macro level, the implementation of hypertension management in Shandong's rural areas was generally in a positive policy environment, such as implementing national policies regarding chronic disease management and publicizing chronic disease management, but the policy framework was not complete, the integration within the departments in the health system was poor, and shortages of professional hypertension managers and sufficient financial support were serious. At the meso level, various medical institutions strived to promote the continuity of medical services, but the organization and deployment of family doctor teams and the promotion and use of information systems still needed to be further strengthened. At the micro level, the cooperation between patients and their families and the family doctor team needed to be improved, and the involvement of patients and their families in hypertension management should be enhanced as well. Conclusion The implementation of hypertension management in Shandong's rural areas is good generally, but the following efforts should be made for improvements: vigorously strengthening the leadership and supervision role of the government, formulating and integrating relevant policies, and promoting the integration of relevant departments; increasing financial support, and addressing the relatively shortage of health human resources and improving the weakness of informatization construction in rural areas to promote the delivery of high-quality medical services; attaching importance to the interaction between patients and families, health service team and community partners to promote patients' self-management.

The purpose of exploring the new theoretical system of college education development is to improve college students’ quality in all aspects. This paper constructs a new theoretical system of college education development based on the new theory of college education development--”three comprehensive education” theory. The fuzzy credibility measure and credibility distribution are used to explain the fuzzy processing theory, and the uncertainty index of the fuzzy processing model is optimized based on the cross-rhombus search algorithm to improve the search speed of the fuzzy processing model. Data experimental analysis is conducted for the fuzzy ICDS multi-optimization principle. Regarding search speed, the average search speed improvement of the algorithm in this paper relative to the CD algorithm saves about 1.37 to 4.69 points per block. It improves classification accuracy by 12.02% and 7.65% compared to the best fuzzy and GFCM algorithms, respectively. This shows that using the fuzzy ICDS multi-optimization principle can help analyze the effectiveness of the “three holistic education” theory in constructing the education development system and provide a reference for planning and implementing the new education development system.

The conventional approach for images encryption entails transforming a regular image into an encrypted image that resembles noise. However, this noise-like encrypted image is susceptible to drawing the attention of an attacker when transmitted through a public channel. Hence, there has been a recent surge in the interest of academics towards visually secure image encryption techniques. In a broad sense, encryption methods that include visual significance should prioritize four key elements: the resemblance between the cypher picture and the carrier image, the capacity for embedding, the attainment of good recovery quality, and resilience against many forms of attacks. To address the issues pertaining to inadequate visual security, limited resistance against attacks, and subpar quality of reconstructed images observed in contemporary image encryption and compression methodologies. This paper proposes a visually secure image encryption method based on improved semi-tensor product compressed sensing, two-way cross zigzag obfuscation, and IWT-HD-SVD embedding. Firstly, the plain image is sparsely represented in the Discrete Wavelet Transform (DWT) domain, and a two-way cross zigzag mismatch strategy is proposed to disarrange the coefficient vectors. Then the plain image is encrypted as a secret image by the improved semi-tensor product compression sensing technique. After that, IWT-HD-SVD embedding technique is proposed to embed the secret image into the carrier image to generate the final meaningful cryptographic image. This dramatically improves the visual security of the cryptographic image. Simulation results show that the quality of the decrypted image is approximately 36 dB and up to 44 dB. In addition, the cryptographic image is highly robust against common noise attacks of 0.05 %.

Cervical cancer is a typical cancer characterized by abnormal cell growth in the cervical area. Ginkgo biloba L. is a deciduous tree of the genus Ginkgo, possessing anti-cancer effects. The aim of this study was to explore the effect of strain J1 from Ginkgo biloba L. on apoptosis of cervical cancer cells. Bacteriostatic activity test, MTT assay and Flow cytometry were used in this study. Crude extract of J1 fermentation reduced cell growth in cervical cancer. The crude extract of the fermentation broth of strain J1 had a good inhibitory effect on Staphylococcus aureus. The crude extract of the J1 fermentation had no toxic effect on normal WISH cells in the range of anti-cervical cancer concentration. Crude extract of J1 fermentation induced apoptosis and regulated cell cycle in cervical cancer. The active compounds were separated and identified by preparative chromatography, and more than ten compounds were obtained. Our study suggests that the crude extract of J1 fermentation from Endophytic fungi of Ginkgo biloba reduced cell growth, and promoted apoptosis of cervical cancer, and is a potential therapeutic strategy for the treatment of cervical carcinoma.

Objective To explore the prognostic factors of the pathological complete response of internal mammary lymph node (ipCR) after neoadjuvant chemotherapy and its effect on breast cancer prognosis. Methods We retrospectively analyzed the clinical data of 70 patients with primary breast cancer with internal mammary lymph node metastasis who received neoadjuvant chemotherapy. Patients were divided into the ipCR group and non-ipCR group based on their postoperative pathology. χ2 test, Fisher, and Logistic regression were used for univariate and multivariate analysis. Meanwhile, the Kaplan-Meier curve and Cox regression were used for prognostic analysis. Results Of 70 patients, 31 obtained ipCR (44.3%). Univariate analysis showed that the expression levels of apCR, HR, and HER2 status were related to ipCR (P < 0.05). Multivariate analysis showed that age, apCR, and HER2 status were independent predictors of ipCR (P < 0.05). The average DFS of ipCR group was better than non-ipCR group (96.0 vs. 67.1 months, P < 0.05). The risk of recurrence and metastasis was 87% lower in the ipCR group than in the non-ipCR group (HR=0.13, 95%CI: 0.04-0.44, P < 0.01). ipCR, Ki67 expression level, and breast pCR (bpCR) were independent factors affecting patients' prognosis. Conclusion There is a correlation between clinico pathological factors and ipCR after neoadjuvant chemotherapy. ipCR can be used to predict the prognosis of patients with internal mammary lymph node metastasis.

In order to achieve China’s “30·60” decarbonization goal, the green and low-carbon transformation of the energy system is the fundamental support; the construction of new-type power system is the key step, and the green certificate is the important voucher to reflect the green value of renewable energy. Currently, the distribution mechanism of green certificates in China is oversimplified, which neither effectively measures the variability of green values generated by different types of renewable energy, nor balances the coordinated development of renewable energy. Therefore, to differentiate the exchange mechanism of green certificates by different types of renewable energy power in this paper, an evaluation index system is established, which describes the difference between green certificates, considering the comprehensive value of renewable energy, and an evaluation model is built with the criteria importance by using the intercriteria correlation (CRITIC) method, the entropy weight method, and the technique for order preference by similarity to an ideal solution (TOPSIS) method. Under the development scenario of peaking carbon emissions before 2030, the impact of the differentiated distribution model on the green incomes of centralized photovoltaic distributed photovoltaic power, onshore wind power, and offshore wind power is analyzed. Moreover, the development plan of renewable energy is modified in consideration of the effect of the differentiated distribution model, and policy suggestions on green certificates are proposed accordingly. The results show that the differentiated distribution model of green certificates is practical to provide corresponding decision-making support to the construction and improvement of green certificates trading mechanism in China.

Objective: This study aimed to realize the high-value utilization of pea protein. Methods: Using pea protein as raw material, ACE inhibitory peptide derived from pea protein was prepared by double-enzyme coordinated enzymatic hydrolysis method, and the ACE inhibition rate, hydrolysis degree and soluble protein content of the hydrolysate were used as indicators to determine the best enzymatic process for the pea ACE inhibitory peptide. Then the ACE inhibitory peptides produced under the optimal enzymatic digestion process were graded by ultrafiltration to explore the effect of molecular weight on the ACE inhibitory activity. Finally, the protective effect of the pea peptide with high ACE inhibitory activity against the injured EA.hy.926 cells was verified by measuring ET-1, MDA content, SOD and NO content levels. Results: The optimal preparation conditions of pea ACE inhibitory peptide by double-enzyme method were as follows: substrate concentration of 100 mg/mL, 3.0% alcalase enzymolysis for 2.0 h at pH 9.5 and 50 ℃, and then adding 3.0% compound protease for 2.0 h at pH 7.0 and 50 ℃. Under these conditions, the IC50 value of ACE inhibition rate of pea protein hydrolysate was 1.141 mg/mL. Peptide components less than 2.5 kDa had the strongest ACE inhibitory activity and could significantly reduce ET-1, MDA content and increase SOD and NO content levels of Ang-induced injured cells. Conclusion: The pea ACE inhibitory peptide was protective against Ang-induced damage to EA.hy.926 cells.

This paper systematically reviews literature related with digital supply chains (DSC) and investigates the application status and development trend of different digital technologies in supply chain management. The review is conducted from the perspective of seven key digital supply chain technologies, i.e. Internet of Things (IoT) & Radio Frequency Identification (RFID), 5th Generation Mobile Communication Technology (5G), 3D Printing, Big data (BD), Blockchain, Digital Twins (DT), and Intelligent autonomous vehicles (IAVs). It highlights the main limitations and opportunities of the various DSC technologies, provides an overview of prior studies, and identifies knowledge gaps by outlining the advantages, weaknesses and restrictions of individual technology. The paper also aims at providing a development framework as a roadmap for the match of different digital technologies with different strategic goals.

We propose how to achieve synthetic PT $\mathcal{PT}$ symmetry in optomechanics without using any active medium. We find that harnessing the Stokes process in such a system can lead to the emergence of exceptional point (EP), i.e., the coalescing of both the eigenvalues and the eigenvectors of the system. By encircling the EP, both nonreciprocal optical amplification and chiral mode switching can be achieved. As a result, our synthetic PT $\mathcal{PT}$ -symmetric optomechanics works as a topological optomechanical amplifier. This provides a surprisingly simplified route to realize PT $\mathcal{PT}$ -symmetric optomechanics, indicating that a wide range of EP devices can be created and utilized for various applications such as topological optical engineering and nanomechanical processing or sensing.

This study aims to explore the relationship between the iodine status and thyroid dysfunction (TD) in pregnant women and establish a model to guide them to prevent excessive iodine intake. A total of 515 pregnant women were enrolled in the study. Urinary iodine concentration (UIC), thyroid hormones, and thyroid autoantibodies were measured, and then a logistic regression model was established. The median UIC of pregnant women was 174 ± 120 μg/L. Multivariate logistic regression analysis indicated that multivitamin supplements containing iodine and frequent seafood consumption were risk factors for excessive iodine (UIC ≥500 μg/L). Besides, excessive iodine was a risk factor for TD. Iodine excess was associated with a high prevalence of TD in pregnant women, especially TPOAb-positive women (P < 0.05). A logistic regression model based on potential risk factors was established to predict the risk of excessive iodine intake among pregnant women and provide guidance to minimize the risk of excessive iodine intake, thus reducing the risk of TD.

ObjectiveTo develop an analytical method for determination of masked fumonisins in cereals by isotope dilution-ultra high performance liquid chromatography-tandem mass spectrometry.MethodsThe samples were extracted and diluted for determination of parental fumonisins. Another portion of extracted samples were alkaline hydrolyzed and cleaned up using strong anionic exchange adsorbent (MAX) for determination of hydrolyzed fumonisins. The chromatographic separation was performed on a CORTECS C18 column (2.1 mm×100 mm, 1.6 μm) using 0.2% formic acid aqueous solution and methanol with 0.2% formic acid as the mobile phase under gradient elution. The six fumonisins of FB1, FB2, FB3, HFB1, HFB2 and HFB3 were analyzed by tandem mass spectrometry using multiple reactions monitoring (MRM) mode. The isotope dilution method was applied for quantitative analysis.ResultsThe six fumonisins showed good linearity with relative coefficients above 0.99. Limits of quantitation (LOQs) were in the range of 5.0-10 μg/kg. At the low, medium and high-spiked levels, the recoveries of fumonisins in three types of cereals were from 88.01% to 114.21%, with precision (RSD) of 0.72%-11.5%.ConclusionThis method is accurate, sensitive and reproducible for the determination of masked fumonisins in cereals. It is suitable for the routine test in analytical chemistry laboratories for monitoring masked fumonisins levels in cereals.

Abstract Background Noninvasive prenatal testing (NIPT) has been widely used clinically to detect fetal chromosomal aneuploidy with high accuracy rates, gradually replacing traditional serological screening. However, the application of NIPT for monogenic diseases is still in an immature stage of exploration. The detection of mutations in peripheral blood of pregnant women requires precise qualitative and quantitative techniques, which limits its application. The bioinformatic strategies based on the SNP (single nucleotide polymorphism) linkage analysis are more practical, which can be divided into two types depending on whether proband information is needed. Hidden Markov Mode (HMM) and Sequential probability ratio test (SPRT) are suitable for families with probands. In contrast, methods based on databases and population demographic information are suitable for families without probands. Methods In this study, we proposed a Spearman rank correlation analysis method to infer the fetal haplotypes based on core family information. Allele frequencies of SNPs that were used to construct parental haplotypes were calculated as sets of nonparametric variables, in contrast to their theoretical values represented by a fetal fraction (FF). The effects on the calculation of the fetal concentration of two DNA enrichment methods, multiple‐PCR amplification, and targeted hybrid capture, were compared, and the heterozygosity distribution of SNPs within pedigrees was analyzed to reveal the best conditions for the model application. Results Predictions of the paternal haplotype inheritance were in line with expectations for both DNA library construction methods, while for maternal haplotype inheritance prediction, the rates were 96.55% for method multiple‐PCR amplification and 95.8% for method targeted hybrid capture. Conclusion Positive prediction rates showed that the maternal haplotype prediction was not as accurate as paternal one, due to the large amount of maternal noise in the mother's peripheral blood. Although this model is relatively immature, it provides a new perspective for noninvasive prenatal clinical tests of monogenic diseases.

BackgroundPostgraduates usually face more life challenges than undergraduate students, including social, emotional and financial issues, and the prevalence of mental health problems in postgraduates is higher than undergraduates. Therefore, the attention on postgraduates’ mental health status is needed.ObjectivesThe current study explored the relationship between postgraduates’ emotional intelligence and well-being by investigating the mediating effects of social support and psychological resilience and the relationship between them through the construction of a chain mediation model.Method1,228 postgraduates completed the Emotional Intelligence Scale, the Social Support Rate Scale, the Psychological Resilience Scale, and the Subject Well-being Scale.ResultsThere is a chain effect between postgraduates’ social support and psychological resilience mediated by their emotional intelligence and well-being, with a total effect value of 0.049.ConclusionEmotional intelligence has a predictive effect on postgraduates’ well-being. The mechanism of this effect includes the indirect effects of social support and psychological resilience. Study results revealed the relationship mechanism between emotional intelligence and postgraduates’ well-being, and provide reference for explorations of how to development postgraduates’ emotional intelligence and further improving their abilities to strengthen their emotional resilience.

Eplerenone is a drug that protects the cardiovascular system. 11α-Hydroxycanrenone is a key intermediate in eplerenone synthesis. We found that although the cytochrome P450 (CYP) enzyme system in Aspergillus ochraceus strain MF018 could catalyse the conversion of canrenone to 11α-hydroxycanrenone, its biocatalytic efficiency is low. To improve the efficiency of 11α-hydroxycanrenone production, the CYP monooxygenase-coding gene of MF018 was predicted and cloned based on whole-genome sequencing results. A recombinant A. ochraceus strain MF010 with the high expression of CYP monooxygenase was then obtained through homologous recombination. The biocatalytic rate of this recombinant strain reached 93 % at 60 h without the addition of organic solvents or surfactants and was 17–18 % higher than that of the MF018 strain. Moreover, the biocatalytic time of the MF010 strain was reduced by more than 30 h compared with that of the MF018 strain. These results show that the recombinant A. ochraceus strain MF010 can overcome the limitation of substrate biocatalytic efficiency and thus holds a high poten tial for application in the industrial production of eplerenone.

Yielding bolt can effectively solve the problem of deep roadway bolt breakage, Y-bolt is one of the common types, but at present, there is a lack of effective numerical simulation technology in engineering application. By analyzing the characteristics of typical static tensile test curve, the tensile mechanical model of Y-bolt is established. The secondary development of built-in cable element in FLAC3D is carried out by using FISH, and the numerical model of Y-bolt is established, forming a complete numerical simulation technology. The numerical simulation of tensile test shows that when the axial force of the bolt reaches 168 kN, it enters the yielding stage, the elongation increases from 10.51 mm to 29.48 mm, and the axial force remains 168 kN, which is in good agreement with the indoor test results. The numerical simulation of deep buried roadway shows that the broken number of Y-bolt is 80% less than that of normal bolt, and the roof settlement and side wall internal displacement are reduced by 50.6 mm and 26.5 mm respectively.

The concrete-filled steel tubular (CFST) arch is a new high-strength support form for a mine roadway in deep/soft rock stratum; however, the bearing characteristics have not been clearly elucidated for scientifically guiding field applications. Numerical simulation tests with 15 schemes shaped as a ‘half circle with two straight legs’ and 10 schemes shaped as a circle were conducted, and the main responses of the numerical model were verified by performing the laboratory tests to evaluate the basic CFST structures and global CFST arches. The bearing and failure behaviors of the CFST arches were studied, and the influence laws, in terms of the arch shape, size and lateral pressure coefficient λ, were further investigated. The results show that the bearing capacity of a circular arch is significantly higher than that of a straight-leg arch under a uniform load. Furthermore, the bearing capacity of the circular arch decreases considerably with the increase in the arch size or λ. In addition, the bearing capacity of a straight-leg arch decreases with the increase in the leg height and arch size; however, it first increases and later decreases with the increase in λ. The failure modes of all the arches correspond to the instability at the extreme point caused by the strength deterioration, except in the case of a circular arch under a uniform pressure, the failure mode of which corresponds to the instability at the branch points. Finally, the recommendations for the field practice are proposed and verified.

The silt-based foamed concrete, in which the cement is partially replaced with silt, has become a novel material in road construction projects. However, at the present time, only a few studies have been completed in which attention was paid the shear strength of the aforementioned type of material in subgrade applications. Therefore, in order to address those issues, this research investigation conducted triaxial shear tests. During the experimental testing processes, the mechanical behaviors of silt-based foamed concrete specimens were examined. Such influencing factors as wet density, silt content and confining pressure levels were considered in the experiments. As indicated by the stress-strain curves of the silt-based foamed concrete, the material had performed well in the elastoplastic model results. The stress-strain curves of the silt-based foamed concrete had displayed both hardening and softening phenomena. In addition, the peak strength and residual strength were observed to both increase to average levels of 0.82 MPa and 0.62 MPa, respectively, as the density increased to 100 kg/m3. Meanwhile, the peak and residual strength levels decreased the mean levels of 16.8% and 12.3%, respectively, when the silt content was increased by 10%. It has been found that the addition of silt will transform pore structures from uniformly distributed sphericity into irregular combined broken bubbles. In addition, increases in silt content could potentially increase the size of pores. The values of the cohesion and friction angles have been observed to greatly increase with higher density levels. The increases in silt content will decrease cohesion. However, the impacts of silt content on friction angles have been found to be complex. In the present research, the shear strength levels corresponding to different normal stress levels were determined.