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Abstract Hepatocyte growth factor (HGF) is a substance that stimulates the proliferation of hepatocytes which promote healing. We developed a macrophage membrane-encapsulated nanosphere drug delivery system containing HGF for the study of burn wound healing. Twenty-seven Sprague–Dawley rats were randomly divided into three groups: a saline control (NS) group, an engineered macrophage membrane-encapsulated nanospheres (ETMM@NPS) group, and an engineered macrophage membrane-encapsulated nanospheres treatment with HGF-loaded gene (HGF@ETMM@NPS) group.The wound tissue sections were examined histologically using hematoxylin and eosin (H&E) and Masson trichrome staining. Immunohistochemistry and Western blotting were performed to determine the expression of relevant proteins. The wound-healing, blood flow and complete epithelialization rates were significantly better in the HGF@ETMM@NPS group compared to the NS and ETMM@NPS groups. Expression of B-cell lymphoma 2-associated X-protein was significantly lower, and B-cell lymphoma 2, cluster of differentiation 31, HGF, alpha smooth muscle actin, and PCNA expression was significantly higher in the HGF@ETMM@NPS group compared with the other two groups. PCNA and HGF expression was significantly up-regulated in the HGF@ETMM@NPS group. The HGF@ETMM@NPS complex drug delivery system used in this research promoted wound healing via effective delivery of HGF to burn wounds, thereby accelerating skin cell growth and migration.

Rainfall and irrigation are the most common driving forces of geological disasters in loess areas. Generally, the infiltration depth is shallow and mainly controlled by microchannels. The pore structure has a significant influence on the seepage characteristics. Aiming to study the distribution of pore structure in shallow loess, this study analyzes the structural samples of loess using CT tomography and mercury intrusion methods in the southern plateau of Jingyang, Shaanxi Province. The changes in meso and micro pore structure characteristics with the burial depth of loess are observed and revealed. The results show that Jingyang shallow loess can be divided into three layers according to its pore structure characteristics: ① 1−2 m as the first layer, 3−4 m as the second layer, and 5 m as the third layer；② The diameter of more than 95% of the total pores are less than 1.0 mm, which mainly are spherical and columnar closed pores; ③ while more than 65% of the total pore are larger than 0.8 mm, and most of them are branched and columnar connected pores；④ With depth increasing, the pore connectivity gradually decreases, and the deformation and failure of macropores play a key role in the stability of loess structure；⑤ In the mercury intrusion test, intragranular pores are bounded by 0.2 μm. The proportion of pores on the left side shows insignificant change with depth, while on the right side, it increases with depth. This study provides a basis for further exploring the micro pore seepage mechanism of shallow loess in the future.

Due to the influence of extreme rainfall and high intensity human engineering activities, the advance speed of the gully head in the Loess Tableland is intensified, which seriously threatens the economic and social development of the Loess Tableland. In recent years, although large-scale Gully Consolidation and Highland Protection (GCHP) projects have effectively inhibited the development of traceable erosion on Loess tableland, there are still serious problems of soil and water erosion. Based on this situation, this study investigated and analyzed the soil erosion diseases of the typical GCHP Projects through field investigation, literature review, and comprehensive analysis. The results show that the hydrology regulation function of GCHP Projects can be divided into the table-land intercept area, gully head cut row area, gully slope cutting line of energy dissipation, and channel held area. Currently, the GCHP suffers from surface water erosion, subsurface erosion of loess engineering geological interface, blockage of drainage channels, and disaster chain of loess gully. The unclear hydrological control mechanism and the mechanism of soil and water mutual feeding erosion disasters are the key scientific challenges of the project. In the future, attention should be paid to the application of biological soil crust, new soil improvement materials, and the complete quality supervision of gully protection tableland engineering. This study can provide basic information for future research on the mechanism of soil and water erosion disasters and engineering planning and design of the Gugou Plateau.

Diabetic foot ulcers, pressure ulcers, and bedsores can easily develop into chronic wounds with bacterial infections, complicating wound healing. This work reports a two-step strategy for treating infected chronic wounds. Firstly, LL37 mimetic peptide-W379 peptides were rapidly released to eliminate the bacterial biofilm on the wound. Then, 3D radially aligned nanofiber scaffolds loaded with W379 antimicrobial peptide and PDGF-BB were used to treat the wound to prevent bacterial infection recurrence and promote angiogenesis and granulation tissue regeneration, thereby accelerating wound healing. In the presented study, we found that the combined use of burst and controlled release of W379 antimicrobial peptide effectively clears the bacterial biofilm and prevents the recurrence of bacterial infection. Additionally, we found that the removal of the bacterial biofilm contributed to modulating the local inflammatory response from a pro-inflammatory type to a pro-regenerative type. Furthermore, the use of PDGF-BB significantly promotes neovascularization and granulation tissue regeneration in the wound bed, resulting in accelerating re-epithelialization and wound closure. Our study provides a promising treatment method for the repair of infected chronic wounds.

This paper proposes a method for passive detection of autonomous underwater vehicle (AUV) wakes using a cilium-inspired wake sensor (CIWS), which can be used for the detection and tracking of AUVs. First, the characteristics of the CIWS and its working principle for detecting underwater flow fields are introduced. Then, a flow velocity sensor is used to measure the flow velocities of the “TS MINI” AUV’s wake at different positions, and a velocity field model of the “TS MINI” AUV’s wake is established. Finally, the wake field of the “TS MINI” AUV was measured at various positions using the CIWS. By analyzing the data, the characteristic frequency of the AUV’s propeller is identified, which is correlated with the AUV’s rotation speed and the number of blades. Through further analysis, a mapping model is established between the spectral amplitude of the characteristic frequency at different positions and the corresponding wake velocity. By substituting this mapping model into the AUV’s wake velocity field model, the possible position range of the sensor relative to the AUV propeller can be estimated. The research provides a technical foundation for underwater detection and tracking missions based on wake detection.

Background Individuals suffering from chronic kidney disease (CKD) frequently face a heightened likelihood of experiencing cardiovascular complications, including heart failure and cardiac mortality. Cardiovascular magnetic resonance feature tracking (CMR-FT) is utilized to assess the micro-contraction function of the myocardium. The objective of this research is to explore the relationship between the left ventricular anatomy, myocardial strain, and the clinical outcomes in patients with CKD. Methods A total of 77 patients with late-stage CKD were enrolled in this retrospective study. They underwent cardiac magnetic resonance imaging and were followed up, with no history of significant cardiac diseases. The patients were divided into two groups: those with a left ventricular global longitudinal strain (LVGLS) ≥ −15.2% (n = 49) and those with LVGLS < −15.2% (n = 28). The clinical endpoints were defined as hospitalization for heart failure or all-cause mortality. Results Over an average observation period of 22 ± 9 months, 11 (14%) patients passed away and 30 (39%) were admitted to the hospital for heart failure, with eight encountering both incidents. Those with LVGLS ≥ −15.2% had markedly lower rates of event-free survival concerning heart failure admissions and overall mortality than their counterparts (log-rank P = 0.014). Cox multivariable analysis indicated that reduced LVGLS consistently predicted a higher likelihood of combined outcomes of heart failure admissions and total mortality (HR: 3.40, 95% CI [1.35–8.56], P = 0.009), even when factoring in age, diabetes, left atrial diameter, and left ventricular mass index (LVMI). However, the LVMI showed no significant correlation with the risk of heart failure admissions or overall mortality. Conclusion Compared to patients with LVGLS < −15.2%, CKD patients with LVGLS ≥ −15.2% have an increased risk of heart failure hospitalization and all-cause mortality. The prognostic role of LVMI in assessing CKD patients among the Asian population requires further investigation.

IntroductionInternal erosion triggered by water pipeline leaks seriously threatens the stability of the urban ground. Hangzhou, a city in Zhejiang Province, China, is facing critical challenges due to urban ground collapse (UGC) caused by internal erosion. However, there is a lack of research on the prevention of UGC by improving the internal erodibility of underground soil. Addressing this issue is of utmost importance to ensure the city’s stability and safety. This paper proposes to improve the internal erodibility of typical sandy silt soils with chemical stabilisers.MethodsThe effects of three chemical stabilisers, lignosulphonate (LS), lime (LI), and lignin fibre (LF), on the critical shear stress (τc) and erosion coefficient (kd) of sandy silt soils were investigated, which from Hangzhou, Zhejiang, China, by the hole erosion test (HET) at different mixing amounts and at different conservation times.ResultsThe findings indicate that LF mainly improves the erosion resistance of sandy silt by increasing τc, and the maximum increase is 2.38 times; LI mainly improves the erosion resistance by decreasing kd, and the maximum decrease is 2.18 times. After adding LS, τc and kd did not change significantly. The scanning electron microscope (SEM) test revealed that the inclusion of LF led to the formation of larger agglomerates in the sandy silt soil. The microstructure of sandy silt soil remained dispersed even after adding LS. Various chemical stabilisers used to improve sandy silt soils exhibited distinct erosion mechanisms. Sandy silt soils improved with LF exfoliated into agglomerates, displaying high resistance to erosion. On the other hand, the sandy silt treated with LF still lacks a protective layer and shows minimal improvements in its ability to withstand erosion. In contrast, the LS-amended sandy silt remains stripped with individual soil particles with insignificant changes in erosion resistance.DiscussionThis study can provide a conceptual framework for choosing foundation treatment techniques in future urban development projects.

The formation mechanism of caves in fissured loess at the edge of the loess platform plateau is complex and is closely related to the occurrence of geological hazards such as landslides, which pose a serious threat to the production and life of people in this region. To address the scientific problem of how internal erosion caves are formed in the fissured loess, four sets of experiments on the formation mechanism of internal erosion caves in loess under different initial fissure opening conditions are carried out using the visualisation of the internal erosion caves formation mechanism model of the fissured loess in the South Plateau of Jingyang as a reference. The results show that the development process from the fractured loess to the internal erosion of caves under water flowing erosion can be divided into three stages, including the hydraulic erosion stage, the infiltration and erosion stage and the gravity collapse stage. The formation mechanism of the internal erosion caves in the fractured loess can be summarized as follows: Softening and sputtering, scouring and widening, erosion and cavitation, and collapsing by gravity. The development rate of seepage erosion in the fractured loess is reflected by the sediment quantity and transport characteristics, which can be divided into the rapid erosion stage, the fluctuation reduction stage and the slow and stable erosion stage. The fracture opening, the erodibility of loess and the ultimate groove depth are important factors affecting the formation of internal erosion caves in the fractured loess. The research results provide theoretical support to further reveal the disaster-causing effects of loess internal erosion.

BackgroundStreptococcus pneumoniae is a common pathogen that colonizes the human upper respiratory tract, causing high morbidity and mortality worldwide. This study aimed to investigate the prevalence status of S. pneumoniae isolated from patients of all ages in Southwest China, including serotype, antibiotic susceptibility and other molecular characteristics, to provide a basis for clinical antibiotic usage and vaccine development.MethodsThis study was conducted from January 2018 to March 2022 at West China Hospital, West China Second University Hospital, First People’s Hospital of Longquanyi District (West China Longquan Hospital), Meishan Women and Children’s Hospital (Alliance Hospital of West China Second University Hospital) and Chengdu Jinjiang Hospital for Women and Children Health. Demographic and clinical characteristics of 263 pneumococcal disease (PD) all-age patients were collected and analyzed. The serotypes, sequence types (STs), and antibiotic resistance of the strains were determined by next-generation sequencing, sequence analysis and the microdilution broth method.ResultsThe most common pneumococcal serotypes were 19F (17.87%), 19A (11.41%), 3 (8.75%), 23F (6.46%) and 6A (5.70%). Coverage rates for PCV10, PCV13, PCV15, PCV20 and PCV24 were 36.12, 61.98, 61.98, 63.12 and 64.26%, respectively. Prevalent STs were ST271 (12.55%), ST320 (11.79%), ST90 (4.18%), ST876 (4.18%) and ST11972 (3.42%). Penicillin-resistant S. pneumoniae (PRSP) accounted for 82.35 and 1.22% of meningitis and nonmeningitis PD cases, respectively. Resistance genes msrD (32.7%), mefA (32.7%), ermB (95.8%), tetM (97.3%) and catTC (7.6%) were found among 263 isolates. Most isolates showed high resistance to erythromycin (96.96%) and tetracycline (79.85%), with more than half being resistant to SXT (58.94%). A few isolates were resistant to AMX (9.89%), CTX (11.03%), MEN (9.13%), OFX (1.14%), LVX (1.14%) and MXF (0.38%). All isolates were susceptible to vancomycin and linezolid.ConclusionOur study provides reliable information, including the prevalence, molecular characterization and antimicrobial resistance of S. pneumoniae isolates causing pneumococcal diseases in Southwest China. The findings contribute to informed and clinical policy decisions for prevention and treatment.

To ensure the safety of life and property of residents on landslides and reveal the deformation and failure law of masonry buildings on landslides, it is necessary to carry out a simulation study on the deformation and failure process of masonry buildings under the action of landslide deformation. A refined model of a masonry building was established based on the contact separation modeling method in ABAQUS, and the viscous contact interface was used to simulate the effect of mortar in the wall. Comparing the results of the numerical simulation with the physical model test results, the main conclusion is as follows: through the comparison of macroscopic deformation characteristics and microscopic stress and strain data obtained from physical and numerical model tests, the load-strain curve of the numerical model test agrees well with that of the physical model test, and their strain clouds are consistent, proving the validity of the numerical simulation method. The law of crack propagation and strain distribution of building walls in landslide tension areas is revealed, which can provide a basis for the protection design of masonry buildings in landslide tension areas.

Pr-doped metal oxide polycrystalline transparent ceramics are highly desirable for photothermal window systems served in extreme environments; however, obtaining efficient photoluminescence (PL) together with high transparency in these ceramics is still posing serious challenges, which undoubtedly limits their applications. Here, Pr-doped Y2Zr2O7 (YZO) transparent ceramics, as an illustrative example, are prepared by a solid-state reaction and vacuum sintering method. Owing to the elimination of defect clusters [PrY4+−O2−−PrY4+] and [PrY4+−e′] without the introduction of impurities and additional defects, the fabricated YZO:Pr ceramics exhibit high transparency (74%) and efficient PL (39-fold enhanced) after air annealing plus vacuum re-annealing treatment. Moreover, upon 295/450 nm excitation, the emission bands (blue, green, red, and dark red) from YZO:Pr ceramics present different temperature-dependent properties due to the thermal-quenching channel generated by the intervalence charge transfer (IVCT) state between Pr3+ and Zr4+ ions. Furthermore, a self-calibrated temperature feedback window with the same fluorescence intensity ratio (FIR) model (I613/I503, where I represents the intensity) under different excitation light sources (295 and 450 nm) is designed. The developed photothermal window operated in a wide temperature range (303–663 K) shows relatively high sensitivities (absolute sensitivity (Sa) and relative sensitivity (Sr) reach 0.008 K−1 at 663 K and 0.47% K−1 at 363 K, respectively), high repeatability (> 98%), and low temperature uncertainty (δT < 3.2 K). This work presents a paradigm for achieving enhanced PL along with elevated transparency of lanthanide (Ln)-doped ceramics through vacuum re-annealing treatment engineering and demonstrates their promising potential for photothermal window systems.

Abstract Background The purpose of this study was to demonstrate both the four-year prevalence trend of healthcare-associated infections (HAIs) in a large tertiary hospital and the trend regarding the prevalence of HAIs following the outbreak of coronavirus disease 2019 (COVID-19) in order to provide evidence of hospital infection management during the COVID-19 pandemic. Methods Based on the hospital’s electronic nosocomial infection databases related to HAIs, we retrospectively identified the HAI cases to assess the epidemiological characteristics of HAIs from January 1, 2018, to December 31, 2021, in a large tertiary hospital in China. Similarly, the trends of HAIs after the COVID-19 outbreak and the seasonal variation of HAIs were further analyzed. Results The HAI cases (n = 7833) were identified from the inpatients (n = 483,258) during the 4 years. The most frequently occurring underlying cause of HAIs was respiratory tract infections (44.47%), followed by bloodstream infections (11.59%), and urinary tract infections (8.69%). The annual prevalence of HAIs decreased from 2.39% in 2018 to 1.41% in 2021 (P = 0.032), with the overall prevalence of HAIs significantly decreasing since the outbreak of COVID-19 (2.20% in 2018–2019 vs. 1.44% in 2020–2021, P

The CLP (Chinese Loess Plateau) is one of the most densely distributed landslides areas. The empirical relationships of the landslides in the CLP remain unclear, and its influencing factors are controversial. According to regional landslide data, this paper studies the relationships and discusses the factors affecting landslides in the CLP. The results show that the area (A) -volume (V) of landslides follows a power law trend described by V = 1.53 A1.19 and the frequency distribution range of H/L (height drop (H)/travel length (L)) is between 0.2 and 1.0, more specifically between 0.2 and 0.4, accounting for 26.1% of the total landslides, indicating that the landslides primarily belong to long run-out landslides. The function of V and H/L of the landslides is followed by H/L = 2.39 V−0.102. About 87% of the landslide is distributed within the equilibrium or mature stages of the watershed. The landslide’s size increases, and the slope of the landslides are steeper with an increase in HI (hypsometric integral). Meanwhile, the loess thickness, human activities, and slope effects on landslides induce landslide occurrence and have positive and negative effects on the landslides within the CLP. With climate change, the risk of landslides will increase in the CLP.

In the present study, the optimization design of the cubic nonlinear damping is conducted for a floating raft isolation system, which can be simplified as a multiple degree-of-freedom system with double parallel freedom inputs. The direct relationship between the power transmissibility and cubic nonlinear damping parameters is derived by taking advantage of the output frequency response function (OFRF) approach. The design requirements are proposed in order to achieve low resonant peak values, low power transmissibility over the high frequency range. The detailed step-by-step design process of the floating raft isolation system applied in a practical vessel is provided. A polynomial function, in terms of the required frequency range, is developed and validated from the simulation data. The case application indicates that the design method determined by the OFRF approach can effectively realize the design requirements of a floating raft isolation system, which can deal with the relationship of the power transmissibility and nonlinear damping parameters.

Multicomponent L12-type material has been shown to be one of the important precipitates used to enhance the properties of high entropy alloys. Its controllability is elusive due to the complexity of the content, which has led to slow progress in the study of their electronic structure. Here, we investigated the deformation mechanism of (Co, Fe, Ni)3Ti-type multicomponent intermetallics using first principles. Thermodynamic parameters, energy and electronic structure suggest that Fe favors a lower γSPF while Ni favors a higher γSPF, which is caused by the difference in the chemical bonding they contribute. The stable outermost electron orbital achieved by Ni-Ti contributes to the good mechanical properties, while the excess lone pair electrons provided by Fe would make the contribution of metallic bonding more significant. Adjustment of the intermetallics-favoring/alloys-favoring element ratio is an effective method to overcome the strength-ductility trade-off. This work provides electronic-level understanding and practical insights to better design and utilize the multicomponent intermetallics enhanced high entropy alloys.

Using bilayer graphene structures (L-type and disk-type structures), we numerically demonstrate a tunable single-band terahertz metamaterial absorber with nearly perfect (100%) absorption by continuously adjusting the graphene Fermi energy parameters to determine the maximum absorption rate, the corresponding center frequency, and bandwidth. Graphene distinct dielectric–metal transition properties make it possible to achieve tunable terahertz absorption. The maximum absorption rate increases from 18% to 100% when the Fermi energy is increased from 0.1 to 1 eV. At 1 eV, the absorption rate exceeds 90% in the range of 0.57–1.03 THz. The incident angle is also tested. When the angle is in the range of 60°, excellent adsorption performance is maintained.

The homojunction provides an effective way to extend the properties of stainless steel, but also leaves more weak points for small atoms to penetrate. In this study, the effects of hydrogen, carbon, and nitrogen atoms at the interface on the austenite/ferrite homojunction were investigated using first principles. This study found that low concentrations of carbon/nitrogen are favorable for the pairing of FCC with BCC compared to hydrogen, which can effectively improve the bonding energy and stability of homogeneous junctions. However, at high concentrations, the interfacial hydrogen can partially act as a mediator for interfacial bonding, which results in a slower decrease in bonding energy. On the contrary, nitrogen causes a sharp decrease in interfacial matching due to excessive strengthening of austenite, which reduces both the binding energy and the stability of the overall system. This study provides valid data and a unique perspective on the development of the austenite/ferrite homojunction.

Objective To investigate the presentations and related clinical characteristics of catatonic symptoms in children with autism spectrum disorder （ASD） by using the Attenuated Behavior Questionnaire （ABQ） and related functional and emotional behavior questionnaires. Methods Children who were diagnosed with ASD in the Third Affiliated Hospital of Sun Yat-sen University or other tertiary hospitals from November 2021 to December 2023 were selected. Reports from parents or long-term caregivers of children with ASD were collected through an online questionnaire. Children with ASD were divided into the ABQ screening positive and negative groups using ABQ questionnaire. Sheehan Disability Scale， Repetitive Behavior Scale-Revised， Children’s Simplified Emotion Scale and Spence children’s Anxiety Scale were used to assess children’s functional impairment and related emotional behavior. Results Four hundred and forty-one valid questionnaires were collected. 166 children with ASD were screened positive by using the ABQ. The total scores of the first six core symptoms， motor symptoms， emotional changes and behavior changes in the ABQ questionnaire of ASD children in the positive group were significantly higher than those in the negative group （all P < 0.001）. All six core motor symptoms were commonly reported in the positive group， with “requiring prompts to complete actions” being the most reported， followed by “immobility， getting stuck， slowness in movement， and problems stopping actions once started”. Over 50% of the children in the positive screening group exhibited these symptoms. The days of functional loss and inefficiency in study/work， social life， family life/family responsibilities， and the proportion of “moderate” or above degree of disability of ASD children in the ABQ-positive group were higher than those in the negative group， and the differences were statistically significant （all P < 0.001）. The scores of stereotypical behaviors， self-injurious behavior， compulsive behavior， sameness/ritual behavior （all P < 0.001）， simplified emotion scale （P < 0.001） and anxiety scale （both P < 0.01） in the ABQ-positive group were significantly higher than those in the ABQ-negative group， and the differences were statistically significant. Conclusions Catatonic symptoms are not uncommon in children with ASD. ASD children complicated with such symptoms tend to exhibit more emotional and behavioral problems， as well as more severe functional impairment， underscoring the need for early identification and intervention.