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In the context of China's urbanization and migration transformation, the phenomenon and trends of job-housing separation have shown new dynamics, necessitating a systematic review of research on this topic in Chinese cities. This study uses CiteSpace to conduct a quantitative analysis of literature on job-housing separation in China from 2000 to 2022. The review is structured according to stages of urban development, with a focus on summarizing and evaluating current research hotspots, themes, and methodologies. The findings indicate that the job-residence separation at different stages of population mobility has different characteristics. Firstly, the research area of job-housing separation has expanded from first-tier cities to second- and third-tier cities, reflecting the new phenomenon of population flow and transition in China's urbanization process. Second, the research perspective has gradually shifted from the macro level to the micro level, paying more attention to the job-housing separation. At the same time, the study actively adopts advanced technologies such as machine learning to process large-scale migration data, and combines multidisciplinary theories such as geography, urbanism, and transportation to conduct in-depth analyses.. Based on this comprehensive review, several key points are identified: (1) In the context of migration transformation, research needs to focus more on the new characteristics of job-housing separation and its spatial correlations from a lifecycle perspective. This involves investigating the social foundations of job-housing separation across multiple scales, including the urban-rural divide, intercity dynamics, and intracity variations. (2) Current research has not adequately explored the evolution of job-housing separation. It is necessary to incorporate life cycle theory to unify each stage of job-housing separation into a dynamic research framework. (3) The use of machine learning techniques should be encouraged to process large-scale migration data. Interdisciplinary approaches, combining geography, urban studies, and transportation, are essential to explore the mechanisms of job-housing separation more comprehensively. This will enable better analysis and prediction of trends, supporting urban planning and the optimization of transportation infrastructure. (4) Integrating migration theories with lifecycle theory can further illuminate the interrelationships between job-housing separation and migration behavior. Research should focus on the impacts of migration on job-housing separation and explore how to address these issues in the context of migration, providing better planning recommendations for urban development. In conclusion, multidimensional and interdisciplinary research is essential to fully understand the dynamics of job-housing separation within the broader context of China's urbanization and migration transformation. By incorporating theories and methodologies from various disciplines, a deeper understanding of the mechanisms and influencing factors can lead to more effective policymaking and sustainable urban development.

This study investigated the effects of the addition of Tremella fuciformis polysaccharides on the zeta potential, particle size, contact angle, storage stability, and rheological properties of curcumin-loaded Pickering emulsion. The results showed that the Pickering emulsion stabilized by T. fuciformis polysaccharides had good stability; its particle size decreased from (8.631 ± 0.057) to (6.031 ± 0.056) μm and its zeta potential increased (–51.60 ± 1.51) to (–65.16 ± 0.59) mV with increasing addition of T. fuciformis polysaccharides from 65% to 85% (V/V), showing improved storage stability. The retention rate of curcumin in the Pickering emulsion with 85% T. fuciformis polysaccharides was more than 80% after 21 days of storage. The rheological results showed that all emulsions exhibited weak gel properties and shear-thinning characteristics. As oil-in-water emulsions, they showed a contact angle of less than 90°. The emulsion retained more than 80% curcumin after heat treatment at 65 ℃. Meanwhile, the emulsion had antibacterial activity against both Escherichia coli and Staphylococcus aureus. The results of this study provide a theoretical reference for the development of new Pickering emulsions with T. fuciformis polysaccharides.

With the rapid development of space-terrestrial integrated communication technologies, the satellite and terrestrial cellular communication industry ecosystems are gradually converging to meet the needs of ubiquitous broadband communication. In order to achieve efficient collaboration between satellite and terrestrial networks in terms of coverage, resources and scheduling, and improve the overall network performance, satellite-terrestrial collaborative networking will be an important direction of space-terrestrial integrated network in the future. Aiming at the goal and vision of space-terrestrial integrated network, the development status and technical challenges of space-terrestrial integrated network were explained, and the satellite-terrestrial integrated network architecture and technical system based on satellite-terrestrial collaborative deployment were proposed innovatively. The key technical schemes of satellite-terrestrial network collaboration at beam-level, service-level and planning-level were analyzed deeply, which provided guidance for the following research on satellite-terrestrial network collaboration technology.

Primary hypertrophic osteoarthropathy(PHO) is a rare disease also known as pachydermoperiostosis. We reported a painless case whose diagnosis was confirmed by genetic test. A 24-year-old male presented a series of symptoms that first began at 14. He suffered from progressive clubbed-fingers accompanied by swelling of the wrist and ankle joints. Facial skin concentric thickening and alar nose broadening appeared simultaneously and increased progressively. He was also prone to acne and hyperhidrosis. X-rays showed thickening of the metacarpal and phalangeal bones, as well as symmetrical periosteal ossification of both the tibia and fibula. Clinical diagnosis of PHO is difficult because of the variable features. With acromegaly excluded, the diagnosis was confirmed by a genetic test. Whole exome sequencing revealed a heterozygous SLCO2A1 c.611C > T(p.Ser204Lue) and SLCO2A1 c.1602C > A(p.Asn534Lys) mutation from each parent. It suggests that primary hypertrophic osteoarthropathy should be considered for young limb hypertrophic patients especially when periosteal thickening signs were showed in X-ray. A confirmatory diagnosis can be made through the genetic test.

Abstract Background Glioblastoma (GBM) is the most aggressive malignant primary brain tumor. The transfer RNA-derived fragments (tRFs) are a new group of small noncoding RNAs, which are dysregulated in many cancers. Until now, the expression and function of tRFs in glioma remain unknown. Methods The expression profiles of tRF subtypes were analyzed using the Cancer Genome Atlas (TCGA)-low-grade gliomas (LGG)/GBM dataset. The target genes of tRFs were subjected to Gene Ontology, Kyoto Encyclopedia and Gene set enrichment analysis of Genes and Genomes pathway enrichment analysis. The protein-protein interaction enrichment analysis was performed by STRING. QRT-PCR was performed to detect the expressions of tRFs in human glioma cell lines U87, U373, U251, and human astrocyte cell line SVG p12. Western blot assay was used to detect to the expression of S100A11. The interaction between tRF-19-R118LOJX and S100A11 mRNA 3’UTR was detected by dual-luciferase reporter assay. The effects of tRF-19-R118LOJX, tRF-19-6SM83OJX and S100A11 on the glioma cell proliferation, migration and in vitro vasculogenic mimicry formation ability were examined by CCK-8 proliferation assay, EdU assay, HoloMonitor cell migration assay and tube formation assay, respectively. Results tRF-19-R118LOJX and tRF-19-6SM83OJX are the most differentially expressed tRFs between LGG and GBM groups. The functional enrichment analysis showed that the target genes of tRF-19-R118LOJX and tRF-19-6SM83OJX are enriched in regulating blood vessel development. The upregulated target genes are linked to adverse survival outcomes in glioma patients. tRF-19-R118LOJX and tRF-19-6SM83OJX were identified to suppress glioma cell proliferation, migration, and in vitro vasculogenic mimicry formation. The mechanism of tRF-19-R118LOJX might be related to its function as an RNA silencer by targeting the S100A11 mRNA 3’UTR. Conclusion tRFs would become novel diagnostic biomarkers and therapeutic targets of glioma, and the mechanism might be related to its post-transcriptionally regulation of gene expression by targeting mRNA 3’UTR.

ObjectiveTo establish an analytical method for determination of three types of citrate ester plasticizers in PVC plastic food contact materials using ultra-high performance liquid chromatography-tandem mass spectrometry.MethodsThe samples were extracted with n-hexane/dichloromethane （1∶1， V/V）， purified via silica gel solid phase extraction column， eluted using acetonitrile/ethyl acetate （1∶4， V/V）， added into a UPLC-MS/MS system， separated by BEH C18 column （2.1 mm × 50 mm， 1.7 μm） with acetonitrile and ultrapure water as mobile phase， detected using an ESI source in MRM positive ion mode， and quantified using an external standard.ResultsThe linear relationship of the method was good and the coefficient of determination （R2） was greater than 0.996. The limits of detection were 0.1-0.6 μg/kg， and the limits of quantitation were 0.3-2.2 μg/kg. The recoveries of the three types of citrate esters plasticizers were 70.3%-103.1%， and the relative standard deviations （RSDs） （n=6） were 0.9%-9.8%.ConclusionThe proposed method is highly sensitive， rapid， and highly applicable， and can meet the requirements for the detection of citrate ester plasticizers in plastic materials， which provides a means to supervise the addition of new plasticizers.

To improve the programming efficiency of a software database, this paper analyzes the possibility of running an embedded system in a software engineering database by constructing an embedded software data programming control system with the help of an independent time step algorithm and main function. By analyzing and calculating the format of DXF files and commonly used group code values, the format of file storage and the method of expressing data in the graphical element processing module are summarized to ensure the accuracy of software processing and the stability of the software processing process. According to the laws summarized in the analysis, the necessity of introducing an embedded system in the software data programming control process was proposed and simulated, and tested. In the test process, we focus on the process time consumption, space resource occupation rate, running accuracy, and step length data. The test results show that the maximum programming process time of the embedded software data programming control system is only 4.5s, the minimum software space resource occupation rate is 19.7%, the highest operation accuracy is 98.9%, and the calculation time per step is about 0.002s, which is significantly better than the programming system based on remote wireless synchronization system and the computer software programming system based on C language technology. The data calculation results of the independent time step algorithm and the main function prove the feasibility of introducing embedded systems in the software programming process and improving the reusability of software programming code for embedded systems.

Soil microorganism studies are crucial in ecological and biological research. However, the lack of standardized analytical methods for sampling makes it challenging to compare studies and obtain consistent results. Therefore, it is essential to establish standardized sampling methods in the field. Our study used a stratification method to collect 120 soil samples from various altitudinal ranges on Cangshan Mountain in China, with an altitude of 4122 m, and incredible microorganism biodiversity. This site provides an ideal landscape for studying elevation patterns in microorganisms. We conducted analyses on the variations of depth and stratification used in the sampling process, as these factors have been found to impact microbial diversity, elevation patterns, and community assembly mechanisms. We found that increasing the sampling depth provided more valuable research results by revealing elevation patterns of soil microorganisms. We therefore recommend sampling to a depth of 35 cm with stratification to determine the overall soil microbial diversity. A depth of 25 cm is suitable for studying elevation patterns with stratification. For investigating community assembly mechanisms without stratification, a depth of 15 cm is recommended. When exploring a specific taxon, the sampling depth can be adjusted accordingly. For studying the elevation pattern of archaea, a depth of 20 cm is appropriate. In the case of fungi, a depth of 40 cm is recommended, while a depth of 20 cm is suitable for studying elevation patterns. This study emphasizes the importance of standardization in sampling methods, particularly along the soil profiles, when studying soil microbiomes in montane areas. These recommendations should be adopted in future research to achieve more consistent and reliable results in the field.

Abstract With the conventional perturbation and observation (P&O) method, photovoltaic (PV) converters have long maximum power point (MPP) tracking times and three‐point oscillations at the steady state that can lead to output power losses and inefficiencies in grid connections. To overcome these drawbacks, a fast tracking and steady‐state‐oscillation‐free control strategy is proposed. The strategy first stores four random duty cycle values on the basis of the duty cycle variation characteristics of the PV panel power adjustment, then calculates the odd and even duty cycle difference and judges the steady state by varying the duty cycle difference threshold. The strategy next obtains the MPP duty cycle using a median filtering algorithm (MFA) to suppress the steady‐state oscillation and improves the tracking speed by resetting the appropriate duty cycle step according to the slope of the PV curve of the PV panel output and the corresponding adaptive coefficients. The proposed algorithm was simulated and experimentally validated under various irradiance conditions, and the results show that the algorithm can improve the PV panel output efficiency compared to both the conventional P&O and the adaptive P&O methods.

Microwave nonreciprocity is in high demand for applications in information processing. Here, we propose an effective approach to realize robust microwave transmission nonreciprocity in a three-mode non-Hermitian cavity magnetic system (CMS). We show that, around the exceptional point, robust microwave nonreciprocity can be achieved within a small detuning range between the cavity and the microwave field. It is fundamentally induced by means of the cavity-magnon interaction and the effective magnon Kerr nonlinearity. Moreover, in the vicinity of the exceptional point, robust microwave transmission nonreciprocity can be realized over an optimal magnetic field range. This greatly improves the operability for obtaining strong microwave nonreciprocity experimentally. This study may stimulate further investigations and applications of the non-Hermitian CMS in structuring high-performance nonreciprocal devices.

Renewable energy DC hydrogen production has become a new development trend. Due to the interaction between the weak damping of DC network and the negative impedance characteristics of power supply of hydrogen production, the actual available power of renewable and hydrogen energy DC interconnection system will be lower than its rated setting value. To solve this problem, this paper proposes an intelligent damping control to realize the rated power operation of hydrogen generation power source and significantly improve the hydrogen generation performance. In this paper, the nonlinear model under typical control strategies is established in order to adapt to different degrees of disturbance, and the damping controller is designed based on state feedback, including feedback control law and damping generation formula. On this basis, an intelligent method of damping control is proposed to support rapid decision-making. Finally, the intelligent damping control method is verified by simulation analysis. It realizes rated power of power supply of hydrogen production by generating only a small amount of damping power and superimposing it on the hydrogen production power.

Objective Bilateral medial medullary infarction (MMI) is prone to misdiagnosis. This study summarizes the clinical characteristics of MMI, in order to provide reference to clinicians. Methods and Results The clinical data of the 3 patients with acute bilateral MMI treated in Ruijin Hospital North Campus affiliated to Shanghai Jiaotong University School of Medicine from January 2017 to January 2022 were collected. All 3 patients had acute onset, one case had acute myelitis⁃like manifestations (rapidly progressive quadriplegia), one case had intractable hiccup, and the other one had unilateral limb numbness and fatigue as the first manifestation, accompanied by hypoglossal palsy. The head MRI showed acute bilateral MMI (one case without acute lesions on early MRI). Two cases were misdiagnosed because of either presenting lower motor neuron damage signs or having atypical symptoms. All patients improved after antithrombotic therapy for acute cerebral infarction. Conclusions The clinical manifestations of acute bilateral MMI are diverse, and it's easy to be misdiagnosed in the early stage. The diagnosis is mainly based on clinical manifestations and head MRI, which requires early recognition and timely antithrombotic treatment for acute cerebral infarction. The main distinguishing points are whether there are risk factors for stroke, upper motor neuron damage signs, and the treatment was effective.

Text classification is a basic and important task in natural language processing.Most of the text classification methods based on deep learning only focus on a single model structure.The single structure lacks the ability to simultaneously capture and utilize both global and local semantic features.Besides,the deepening of the network will lose more semantic information.In order to overcome the above problems,a text classification model FMNN which is a text classification model fused with multiple neural network is proposed in this paper.The model combines the performances of BERT,RNN,CNN and Attention while minimizing the network depth.BERT is used as the embedding layer to obtain the matrix representation of the text.BiLSTM and Attention are used to jointly extract the global semantic features of the text.CNN is used to extract the local semantic features of the text at multiple granularities.The global semantic features and local semantic features are applied to the softmax classifier respectively.The results are finally fused by arithmetic average.The experimental results on three public data sets and one judicial data set show that the proposed FMNN model achieves higher accuracy rate,and the accuracy rate on the judicial data set reaches 90.31%,which proves that the model has good practical value.

Objective To investigate the differences of peripheral blood DNA methylation in identical twin adolescents with different depressive phenotypes and explore whether these differentially expressed genes can be used as candidate genes involved in the occurrence of depression. Methods Three pairs of verified identical twin adolescents (12~18 years old) were recruited in this study. Phenotypic differences of depression between the twins were determined by Beck Depression Inventory-Ⅱ (BDI-Ⅱ) scores and emotional factor scores of Strength and Difficulty Questionnaire (SDQ) for students. After Infinium MethylationEPIC BeadChip Kit was used to interrogate over 850k methylation sites, those with P < 0.05 and the absolute value difference of methylation β value greater than 0.1 (|△β| >0.1) were selected as the differential methylation sites. Gene Ontology (GO) functional annotation analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, as well as protein-protein interaction (PPI) network were performed to identify important genes associated with major depressive disorder (MDD) and their methylation changes. Results Three pairs of identical twin adolescents with different depressive phenotypes were divided into depressive phenotype group and normal phenotype group. A total of 57 genes with different methylation levels were screened between the 2 groups, including 45 genes with increased and 12 genes with decreased DNA methylation levels. GO analysis showed that differential genes were most significantly enriched in biological processes such as central nervous system development and regulation of RNA metabolic process. KEGG analysis indicated that differential genes were significantly enriched in synaptic long-term depression (LTD), PI3K-Akt signaling pathway and TNF signaling pathway. Besides, direct or indirect interactions between RHOA and several differential methylated genes were found in PPI network. Conclusion Changes in DNA methylation levels of CSF1R, NOS1, AHR and other genes in peripheral blood of identical twins with different depressive phenotypes may regulate gene expression through synaptic long-term depression (LTD), PI3C-Akt and other signaling pathways involved in the occurrence of depression.

The Buck circuit is a common topology in DC-DC converter. The existing control strategies have the advantages of short modulation time and high dynamic performance, but they also have the disadvantages of poor active modulation of the working mode of the converter and large current stress. In response to the above problems, an improved frequency/amplitude modulation control strategy is proposed in this paper. The relationship between the output power and the peak inductor current in three modes, namely, Discontinuous Conduction Mode Critical Conduction Mode (CRM) and Continuous Conduction Mode is derived. The precise control strategy of the inductor peak current is introduced based on the traditional voltage loop control strategy to realize the free control of the system working mode and reduce the current stress during the working process. Finally, the experimental platforms of 100V/12V and 220/80V are established respectively. The experimental results show that the flexible switching circuit operating mode in the full load range can be realized under the new control method. In the 100/12V experimental platform, the current stress of the switch tube is optimized by at least 10.7%, and the average system efficiency is improved by 2.21%, with the same main circuit parameters.

ObjectiveTo analyze the characteristics of sudden death associated with sexual activity to provide recommendations for forensic identification.MethodsA retrospective analysis was conducted on autopsy cases accepted by Forensic Identification Center of Huazhong University of Science and Technology from 1998 to 2018, and a total of 15 cases of sudden death associated with sexual activity were screened out. The general information, case data and pathological changes of 15 cases were collected to find the relationship between sexual activity and sudden death.ResultsThe ratio of male to female was 1.5∶1. The average age of males was 50.1 years and that of females was 35.0 years. Coronary artery diseases and brain diseases accounted for most of the cases （12/15）. Sexual partners were associated with locations of deaths and body dumping behaviors.ConclusionSudden death associated with sexual activity, although rare, may occur in people over 30 years old with pre-existing heart or brain diseases, which should be paid attention to in forensic practice.

We describe IXPE polarization observations of the pulsar wind nebula (PWN) MSH 15−5 ^2 , the “Cosmic Hand.” We find X-ray polarization across the PWN, with B -field vectors generally aligned with filamentary X-ray structures. High-significance polarization is seen in arcs surrounding the pulsar and toward the end of the “jet,” with polarization degree PD > 70%, thus approaching the maximum allowed synchrotron value. In contrast, the base of the jet has lower polarization, indicating a complex magnetic field at significant angle to the jet axis. We also detect significant polarization from PSR B1509−58 itself. Although only the central pulse phase bin of the pulse has high individual significance, flanking bins provide lower-significance detections and, in conjunction with the X-ray image and radio polarization, can be used to constrain rotating vector model solutions for the pulsar geometry.

Vortex field in photonic metamaterials has been revealed in recent years, which provides an extra degree of freedom to control the behavior of electromagnetic waves, such as the unidirectional propagation in topological metamaterials and orbital angular momentum multiplexing in optical fibers. Achieving topologically protected unidirectionality needs an external source either with a vortex index of m = ±1 (i.e. 2πm phase winding around phase singularity) or with a spin index of ±1 (i.e. right- or left-handed circular polarization). However, it is still an open question on the relationship between higher-order (|m | > 1) vortex field and topological metamaterials. Here, we study the excitation of valley bulk states by a source with a higher-order vortex index in Kagome photonic crystals. The selection rule for the excitation of valley bulk states is derived and can be applied to predict the selective excitation of valley bulk states by a source with a higher-order vortex index. Interestingly, we find that the Fourier spectrum and the averaged Fourier spectrum of the Ez component enable us to identify the vortex index of the source. Besides, it is shown that the unidirectional edge states can be excited by a source with a vortex index of 1 or 2 in a straight or 120° detour waveguide. Our work paves the way for the demonstration of the selection rule and may have potential applications in optical mode identification.

The connecting rod breaked in the logo position at the middle of the connecting rod body, when it was subjected to cyclin load fatigue experiment. The material and manufacturing process of the experimental samples were checked and there was no defect. The three-dimension solid model of the experimental connecting rod was built by 3-D modeling software, and the stress concentration had occurred at the same location logo with the experimental sample connecting rod by using finite element method. Then three schemes were designed and the influence on the distance between the logo words, the height of logo to connecting rod body surface and the positing of the logo to stress were analysis, the results showed that: the stress was reduced by appropriately increasing the spacing between logo words. The depressing logo could greatly reduce the stress comparing with the protruding logo. The positon of the logo had the most influence to the stress, and the stress concentration of the connecting rod disappeared when the logo moved from middle of the connecting rod to the outside of the connecting rod cap.

Energy storage and virtual power plant technologies have been developed and become important technical means to enhance power system stability and reduce real-time dispatching costs. In this study, the dispatching capability and dispatching cost characteristics of the virtual power plants are analysed firstly in detail, as well as the dispatching difficulties under the traditional market modes. Hence, virtual power plant real-time bidding package model and virtual auction-based real-time power market mechanism are proposed. Data-driven virtual power plant real-time packing method and bidding package model integrated virtual Vickrey–Clarke–Groves auction model are put forward. Finally, the feasibility and validity of the proposed mechanism and method are verified by case studies and result in analyses of the IEEE-30 bus test system with multiple virtual power plants, providing a scientific foundation and a practical solution to the real-time power market.

Objectives Based on an analysis of the signal noise characteristics of an inertial measurement unit (IMU) accelerometer, the noise was studied in the wavelet domain.Methods In order to solve the limitations of the traditional Fourier filtering method for nonlinear noise processing such as Gaussian white noise, this paper uses the two aspects of wavelet threshold estimation and threshold processing function to optimize the existing wavelet theory, and proposes a new wavelet threshold denoising algorithm which can simplify the computational complexity of wavelet analysis while effectively improving the performance of small noise reduction. On this basis, the implementation of the new wavelet threshold algorithm on a field-programmable gate array (FPGA) is studied and the system's performance is tested.Results The results show that the effective resolution of the accelerometer acquisition circuit processed by the new wavelet algorithm can reach more than 22.4 bits, and the effective resolution is improved by 1.6 bits compared with the original signal.Conclusions The results show that the new wavelet algorithm is better than the traditional Fourier filtering and traditional wavelet filtering method in improving the signal-to-noise ratio or reducing the root mean square error, by virtue of which it meets the real-time requirements of signal processing.