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The Laasraoui segmented and Arrhenius flow stress model, dynamic recrystallization (DRX) model, grain size prediction model, and hot processing map (HPM) of Fe-Cr-Mo-Mn steels were established through isothermal compression tests. The models and HPM were proven by experiment to be highly accurate. As the deformation temperature decreased or the strain rate increased, the flow stress increased and the grain size of the Fe-Cr-Mo-Mn steel decreased, while the volume fraction of DRX (Xdrx) decreased. The optimal range of the hot processing was determined to be 1050-1200 °C/0.369-1 s-1. Zigzag-like grain boundaries (GBs) and intergranular cracks were found in the unstable region, in which the disordered martensitic structure was observed. The orderly packet martensite was formed in the general processing region, and the mixed structure with incomplete DRX grains was composed of coarse and fine grains. The microstructure in the optimum processing region was composed of DRX grains and the multistage martensite. The validity of the Laasraoui segmented flow stress model, DRX model, grain size prediction model, and HPM was verified by upsetting tests.
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The coastal zone serves as a crucial hub for economic and population concentration. Amid the context of high-intensity development and global climate change, uncertain risks from diverse sources-including extreme weather events (i.e., high temperatures, typhoons, and excessive precipitation), natural disasters (i.e., floods, tsunamis, landslides, and mudslides), and societal disruptions (i.e., economic crises and viral diseases)-are escalating rapidly. Enhancing coastal resilience to minimize these risk impacts is progressively becoming a mandatory requirement for the sustainable development of coastal zones. However, existing research primarily focuses on distinct disasters, the ecological environment, or specific socio-economic aspects, thereby lacking a comprehensive theoretical framework and thorough analysis of the factors influencing coastal resilience. Here, we construct a theoretical framework centered on the unique traits and processes of coastal resilience, analyze the spatiotemporal evolution characteristics of coastal resilience from a grid and administrative division standpoint, and utilize geographic detectors to determine the factors influencing coastal resilience while considering the modifiable areal unit problem (MAUP). Our findings indicate that: (1) Coastal resilience in the East China Sea (ECS) initially declined but then increased, transitioning from a lower to a medium level. Barring the pressure index, other dimensional indices had an upward trend; (2) Continuous improvements were observed in coastal resilience across different land uses. Forests, waters, and oceans demonstrated higher resilience levels than other lands, with construction land resilience developing swiftly. The effect of changes in land use types on coastal resilience showed a rapid initial increase and subsequent decrease; (3) The change pattern of coastal resilience in the ECS is mainly unchanged and slightly increased. Areas with the most drastic changes were concentrated in Shanghai, northern Zhejiang, and central Fujian, with the main change patterns continuously rising; (4) The primary factors influencing coastal resilience in the ECS included gross domestic product and infrastructure construction level. Advanced industrial structure, technological and educational prowess, and effective government management are important determinants of coastal resilience development. The significance of human factors continues to grow. Our findings offer valuable insights for optimizing national spatial planning of coastal zones, responding to internal and external impacts, achieving resilient coastal zones, and implementing a comprehensive sustainable management approach.
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Several studies have suggested an association between exposure to various metals and the onset of type 2 diabetes (T2D). However, the results vary across different studies. We aimed to investigate the associations between serum metal concentrations and the risk of developing T2D among 8734 participants using a prospective cohort study design. We utilized inductively coupled plasmamass spectrometry (ICP-MS) to assess the serum concentrations of 27 metals. Cox regression was applied to calculate the hazard ratios (HRs) for the associations between serum metal concentrations on the risk of developing T2D. Additionally, 196 incident T2D cases and 208 healthy control participants were randomly selected for serum metabolite measurement using an untargeted metabolomics approach to evaluate the mediating role of serum metabolite in the relationship between serum metal concentrations and the risk of developing T2D with a nested casecontrol study design. In the cohort study, after Bonferroni correction, the serum concentrations of zinc (Zn), mercury (Hg), and thallium (Tl) were positively associated with the risk of developing T2D, whereas the serum concentrations of manganese (Mn), molybdenum (Mo), barium (Ba), lutetium (Lu), and lead (Pb) were negatively associated with the risk of developing T2D. After adding these eight metals, the predictive ability increased significantly compared with that of the traditional clinical model (AUC: 0.791 vs. 0.772, P=8.85×10-5). In the nested casecontrol study, a machine learning analysis revealed that the serum concentrations of 14 out of 1579 detected metabolites were associated with the risk of developing T2D. According to generalized linear regression models, 7 of these metabolites were significantly associated with the serum concentrations of the identified metals. The mediation analysis showed that two metabolites (2-methyl-1,2-dihydrophthalazin-1-one and mestranol) mediated 46.81% and 58.70%, respectively, of the association between the serum Pb concentration and the risk of developing T2D. Our study suggested that serum Mn, Zn, Mo, Ba, Lu, Hg, Tl, and Pb were associated with T2D risk. Two metabolites mediated the associations between the serum Pb concentration and the risk of developing T2D.
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Diabetes Mellitus Tipo 2 , Metales , Humanos , Diabetes Mellitus Tipo 2/sangre , Estudios Prospectivos , Masculino , Femenino , Persona de Mediana Edad , China , Metales/sangre , Adulto , Anciano , Contaminantes Ambientales/sangre , Estudios de Cohortes , Metabolómica , Estudios de Casos y Controles , Talio/sangre , Exposición a Riesgos Ambientales/estadística & datos numéricos , Pueblos del Este de AsiaRESUMEN
Partial discharge detection is considered a crucial technique for evaluating insulation performance and identifying defect types in cable terminals of high-speed electric multiple units (EMUs). In this study, terminal samples exhibiting four typical defects were prepared from high-speed EMUs. A cable discharge testing system, utilizing high-frequency current sensing, was developed to collect discharge signals, and datasets corresponding to these defects were established. This study proposes the use of the convolutional neural network (CNN) for the classification of discharge signals associated with specific defects, comparing this method with two existing neural network (NN)-based classification models that employ the back-propagation NN and the radial basis function NN, respectively. The comparative results demonstrate that the CNN-based model excels in accurately identifying signals from various defect types in the cable terminals of high-speed EMUs, surpassing the two existing NN-based classification models.
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This paper addresses the resilient event-triggering adaptive neural network (NN) control problem for networked control systems under mixed cyber attacks. Compared with the conventional event-triggered mechanism (ETM) with constant threshold, a novel resilient ETM is designed to withstand the affect of denial-of-service attacks and conserve communication resources. Different from the energy-bounded deception attacks, an unknown state-dependent nonlinear attack signal is considered in this work. To identify the deception attack, the NN technique is utilized to approximate the unknown attack signal. Subsequently, an adaptive controller is established to compensate for the malicious affects of deception attacks on the system. Furthermore, sufficient conditions for the boundedness of the system are derived via applying the Lyapunov functional, and a co-design strategy for control gain and event-triggering parameter is provided. Finally, the feasibility of the proposed approach is validated through a robot manipulator system.
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Comunicación , Resiliencia Psicológica , Redes Neurales de la ComputaciónRESUMEN
OBJECTIVE: To analyze the clinical and genetic characteristics of ten Chinese pedigrees affected with 7q11.23 duplication syndrome. METHODS: From December 2017 to January 2022, ten pedigrees diagnosed with 7q11.23 duplication syndrome at the First Affiliated Hospital of Zhengzhou University were enrolled as the study subjects. Clinical data of all subjects were collected, and some had subjected to copy number variation sequencing or single nucleotide polymorphism array to analyze the pattern of inheritance. RESULTS: The probands had included six fetuses and four adolescents. Four of the six prenatal cases showed abnormal ultrasound indicators, including three with soft indicators and one with abnormal fetal structural development. The clinical phenotype of the four adolescent cases had included mental retardation, delayed language development, and attention deficit hyperactivity disorder. The size of the copy number variations had ranged from 1.31 to 1.42 Mb, involving the classic region of 7q11.23 duplication syndrome. Of these, five cases had undergone parental origin testing, three cases were de novo, and two were hereditary. CONCLUSION: Individuals with 7q11.23 duplication syndrome may show substantial clinical phenotypic heterogeneity, hence the affected families should be provided with pre-pregnancy consultation and reproductive guidance.
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Variaciones en el Número de Copia de ADN , Discapacidad Intelectual , Embarazo , Femenino , Adolescente , Humanos , Linaje , Discapacidad Intelectual/genética , Síndrome , ChinaRESUMEN
Inflammatory bowel disease (IBD) is a chronic and recurrent intestinal inflammatory disease, mainly including Crohn's disease (CD) and ulcerative colitis (UC). In recent years, the incidence and prevalence of IBD have been on the rise worldwide and have become a significant concern of health and a huge economic burden on patients. The occurrence and development of IBD involve a variety of pathogenic factors. The changes in short-chain fatty acids (SCFAs) are considered to be an important pathogenic mechanism of this disease. SCFAs are important metabolites in the intestinal microbial environment, which are closely involved in regulating immune, anti-tumor, and anti-inflammatory activities. Changes in metabolite levels can reflect the homeostasis of the intestinal microflora. Recent studies have shown that SCFAs provide energy for host cells and intestinal microflora, shape the intestinal environment, and regulate the immune system, thereby regulating intestinal physiology. SCFAs can effectively reduce the incidence of enteritis, cardiovascular disease, colon cancer, obesity, and diabetes, and also play an important role in maintaining the balance of energy metabolism (mainly glucose metabolism) and improving insulin tolerance. In recent years, many studies have shown that numerous decoctions and natural compounds of traditional Chinese medicine have shown promising therapeutic activities in multiple animal models of colitis and thus attracted increasing attention from scientists in the study of IBD treatment. Some of these traditional Chinese medicines or compounds can effectively alleviate colonic inflammation and clinical symptoms by regulating the generation of SCFAs. This study reviews the effects of various traditional Chinese medicines or bioactive substances on the production of SCFAs and their potential impacts on the severity of colonic inflammation. On this basis, we discussed the mechanism of SCFAs in regulating IBD-associated inflammation, as well as the related regulatory factors and signaling pathways. In addition, we provide our understanding of the limitations of current research and the prospects for future studies on the development of new IBD therapies by targeting SCFAs. This review may widen our understanding of the effect of traditional medicine from the view of SCFAs and their role in alleviating IBD animal models, thus contributing to the studies of IBD researchers.
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Colitis , Enfermedades Inflamatorias del Intestino , Animales , Humanos , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Medicina Tradicional , Medicina Tradicional China , InflamaciónRESUMEN
Lithium metal batteries (LMBs) are expected to upgrade their energy density to meet the growing battery market demand; however, intractable lithium dendrites and prominent electrode-electrolyte interface problems have been the stumbling block to their practical applications. Electrolytes play a crucial role in LMBs and are directly involved in the establishment of the electrode-electrolyte interface. In particular, low-concentration electrolytes (LCEs) can significantly save electrolyte costs, but the interface issue is more noteworthy. Here, multifunctional acetamide (N-methyl-N-(trimethylsilyl)-trifluoroacetamide, MTA) and lithium nitrate (LiNO3) additives were introduced together to enhance the performance of LMBs in LCEs. The MTA additive effectively removes the trace water and corrosive HF from the electrolyte, thus suppressing lithium salt decomposition and enhancing the stability of LCEs. Moreover, the MTA additive can construct an inorganic-rich interphase layer on the cathode/anode surface to protect the electrode. Especially, MTA can cooperate with LiNO3 additive to suppress lithium dendrites and reduce interfacial impedance, thus effectively enhancing lithium metal anode stability. Benefiting from the introduction of MTA and LiNO3 additives in the LCEs, the Li||NMC811 metal battery still has a capacity of 110 mA h g-1 after 500 cycles at room temperature, while the reference batteries have failed. The rate capacity and high temperature (50 °C) performance of the Li||NCM811 batteries have also been significantly improved. Significantly, this research explores a cost-effective method of using multifunctional additives to enhance LMBs' stability in LCEs.
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Thermo-optic phase shifters (TOPSs) are commonly used in large-scale silicon photonic integrated optical phased arrays (OPAs). However, fast-response TOPSs consume relatively high power; the elevated temperature floor in the dense region of the TOPSs introduces thermal crosstalk between optical paths, which undermines the control accuracy. We propose a combined method that involves subarray design in the optical power distribution network and array control method to predict, optimize, and redistribute the phase shifts and mitigates thermal crosstalk. Thermal simulations and an array control method for generic OPA models are discussed. A silicon photonic chip prototype of a 4 × 4 OPA with three-level cascaded subarrays is fabricated to demonstrate the proposed method. The experimental and statistical results show that the method effectively reduces the average total power consumption by 31%, the maximum local temperature by 18.4%, and the thermal crosstalk within the OPA.
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BACKGROUND: Portulaca grandiflora is a tiny, upright herb that contains a variety of chemical components, including alkaloids, glycosides, mucilage, proteins, tannins, flavonoids, saponins, polysaccharides, and triterpenoids possessing properties that may help with atherosclerosis. The reported pharmacological properties of Portulaca grandiflora are antioxidant, antidiabetic, antiasthmatic, antibacterial, antiulcer and anti-inflammatory properties. OBJECTIVES: The yield of methanol extract is higher than that of ethanol and acetone, and its phytoconstituents, like flavonoids and polyphenols, and has potent antioxidant properties. In order to determine the effectiveness ofPortulaca grandiflora methanol extract fraction against high-fat diet (HFD)-induced hyperlipidemia, hemodynamic change, antioxidant levels, and vascular dysfunction in rats, a study was carried out on a flavonoid-rich methanol extract fraction of the aerial part of Portulaca grandiflora Hook. METHODS: This method involves a study of 30 days involving male Wistar rats (240-250 g) (n=5) that were fed with an Ath diet. Study groups were divided into (i) The Control Group, (ii) the Diseases Control Group, (iii) Disease + Standard drug (Atorvastatin 20mg/kg, orally, (iv) Disease + Test Extract dose 1 (Portulaca grandiflora 200mg/kg orally), and (v) Disease + Test Extract dose 2 (Portulaca grandiflora 400mg/kg orally). Both the test drug Portulaca grandiflora and the standard drug Atorvastatin were given orally for 30 days. RESULTS: At the end of the study, blood samples were taken to measure the serum lipid profile, alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, and levels of oxidative tissue stress. Hemodynamic parameters and aortic staining were performed. Portulaca grandiflora treatment improved the lipid profile and considerably reduced oxidative stress levels. Aortic staining examination revealed a marked reduction in atherosclerotic lesions. CONCLUSION: These results revealed that Portulaca grandiflora is an effective treatment approach in preventing atherosclerotic lesion progression, which is attributed to its protection against oxidative stress and various enzymatic activities in the Atherogenic model.
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Ulcerative colitis (UC) is an idiopathic inflammatory disease mainly affects the large bowel and the rectum. The pathogenesis of this disease has not been fully elucidated, while the disruption of the intestinal barrier function triggered by various stimulating factors related to the host genetics, immunity, gut microbiota, and environment has been considered to be major mechanisms that affect the development of UC. Given the limited effective therapies, the treatment of this disease is not ideal and its incidence and prevalence are increasing. Therefore, developing new therapies with high efficiency and efficacy is important for treating UC. Many recent studies disclosed that numerous herbal decoctions and natural compounds derived from traditional herbal medicine showed promising therapeutic activities in animal models of colitis and have gained increasing attention from scientists in the study of UC. Some of these decoctions and compounds can effectively alleviate colonic inflammation and relieve clinical symptoms in animal models of colitis via regulating intestinal barrier function. While no study is available to review the underlying mechanisms of these potential therapies in regulating the integrity and function of the intestinal barrier. This review aims to summarize the effects of various herbal decoctions or bioactive compounds on the severity of colonic inflammation via various mechanisms, mainly including regulating the production of tight junction proteins, mucins, the composition of gut microbiota and microbial-associated metabolites, the infiltration of inflammatory cells and mediators, and the oxidative stress in the gut. On this basis, we discussed the related regulators and the affected signaling pathways of the mentioned traditional medicine in modulating the disruption or restoration of the intestinal barrier, such as NF-κB/MAPK, PI3K, and HIF-1α signaling pathways. In addition, the possible limitations of current studies and a prospect for future investigation and development of new UC therapies are provided based on our knowledge and current understanding. This review may improve our understanding of the current progression in studies of traditional medicine-derived therapies in protecting the intestinal barrier function and their roles in alleviating animal models of UC. It may be beneficial to the work of researchers in both basic and translational studies of UC.
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Oxidative stress is integral in the development of atherosclerosis, but knowledge of how oxidative stress affects atherosclerosis remains insufficient. Here, we design a multiplexed diagnostic tool that includes two functions (photoacoustic imaging and urinalysis), for assessing intraplaque and urinary malondialdehyde (MDA), a well-recognized end-product of oxidative stress. Molecular design is conducted to develop the first near-infrared MDA-responsive molecule (MRM). Acid-unlocked ratiometric photoacoustic nanoprobe is designed to report intraplaque MDA, enabling it to reflect plaque burden. Furthermore, MRM is tailored for urinary MDA detection with excellent specificity in a blind study. Moreover, we found a significant difference in urinary MDA between healthy adults and atherosclerotic patients (more than 600 participants). Combining these two functions, such a multiplexed diagnostic tool can dynamically report intraplaque and systemic oxidative stress levels during atherosclerosis progression, pneumonia infection, and drug treatment in atherosclerotic mice, which is promising for the auxiliary diagnosis of atherosclerosis.
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Aterosclerosis , Placa Aterosclerótica , Adulto , Humanos , Animales , Ratones , Aterosclerosis/diagnóstico , Placa Aterosclerótica/diagnóstico , Biomarcadores , Estrés OxidativoRESUMEN
BACKGROUND: Frailty has been associated with a higher incidence of overall postoperative complications and mortality. However, the influence of frailty on the risk of venous thromboembolism (VTE) in patients with hip fracture following surgery remains unclear. We performed a meta-analysis to systematically evaluate the above association. METHODS: PubMed, Embase, Cochrane Library, Wanfang and CNKI were searched for relevant observational studies comparing the incidence of postoperative VTE in patients of hip fracture with and without frailty. Data collection, literature searching, and statistical analysis were conducted independently by two authors. Using a heterogeneity-incorporating random-effects model, the results were pooled. RESULTS: In this meta-analysis, 9509 patients from nine cohort studies were included. Pooled results showed that compared to those without frailty, patients with frailty at admission had a higher incidence of postoperative VTE (odds ratio [OR]: 2.59, 95% confidence interval [CI]: 1.25-5.39, p = 0.01; I2 = 66%). Subgroup analysis suggested the association between frailty and postoperative VTE was more remarkable in studies of patients with frailty prevalence < 50% (OR 6.28, 95% CI 3.31-11.90, p < 0.001; I2 = 8%) as compared to those ≥ 50% (OR 1.30, 95% CI 0.80-2.11, p = 0.28; I2 = 0%; p for subgroup difference < 0.001). Further meta-analyses showed that frailty at baseline was associated with a higher incidence of deep venous thrombosis (OR 3.15, 95% CI 1.33-7.47, p = 0.009; I2 = 59%), but not pulmonary embolism (OR 1.13, 95% CI 0.59-2.16, p = 0.72; I2 = 0%). CONCLUSION: Frailty is associated with a higher incidence of postoperative VTE in patients with hip fracture.
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Fragilidad , Fracturas de Cadera , Embolia Pulmonar , Tromboembolia Venosa , Humanos , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiología , Anticoagulantes , Fragilidad/complicaciones , Embolia Pulmonar/complicaciones , Fracturas de Cadera/complicaciones , Factores de RiesgoRESUMEN
The aim of this study was to generate a polygenic risk score (PRS) for type 2 diabetes (T2D) and test whether it could be used in identifying high-risk individuals for lifestyle intervention in a Chinese cohort. We genotyped 80 genetic variants among 5024 participants without non-communicable diseases at baseline in the Wuxi Non-Communicable Diseases cohort (Wuxi NCDs cohort). During the follow-up period of 14 years, 440 cases of T2D were newly diagnosed. Using Cox regression, we found that the PRS of 46 SNPs identified by the East Asians was relevant to the future T2D. Participants with a high PRS (top quintile) had a two-fold higher risk of T2D than the bottom quintile (hazard ratio: 2.06, 95% confidence interval: 1.42-2.97). Lifestyle factors were considered, including cigarette smoking, alcohol consumption, physical exercise, diet, body mass index (BMI), and waist circumference (WC). Among high-PRS individuals, the 10-year incidence of T2D slumped from 6.77% to 3.28% for participants having ideal lifestyles (4-6 healthy lifestyle factors) compared with poor lifestyles (0-2 healthy lifestyle factors). When integrating the high PRS, the 10-year T2D risk of low-clinical-risk individuals exceeded that of high-clinical-risk individuals with a low PRS (3.34% vs. 2.91%). These findings suggest that the PRS of 46 SNPs could be used in identifying high-risk individuals and improve the risk stratification defined by traditional clinical risk factors for T2D. Healthy lifestyles can reduce the risk of a high PRS, which indicates the potential utility in early screening and precise prevention.
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Diabetes Mellitus Tipo 2 , Enfermedades no Transmisibles , Humanos , Estudios de Cohortes , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/genética , Pueblos del Este de Asia , Estilo de Vida , Estudios Prospectivos , Factores de Riesgo , Herencia MultifactorialRESUMEN
In order to investigate the effects of RNAi-mediated survivin and hypoxia-inducible factor 1α (HIF-1α) gene silencing on the proliferation and apoptosis of gastric cancer BGC-823 cells, small interfering RNAs (siRNAs) targeting survivin and HIF-1α mRNAs, respectively, as well as scrambled siRNAs (SCRs) were designed and synthesized, namely siRNA-survivin group, siRNA-HIF-1α group, and SCR group. The hypoxia-sensitive gastric cancer BGC-823 cells were identified and transfected in vitro with Hifectin II under hypoxic conditions, and the expression of survivin and HIF-1α was assessed by RT-PCR and Western blotting assays, respectively. The ability of apoptosis, proliferation, invasion, and migration was measured, and the results showed that HIF-1α expression was significantly increased in BGC-823 cells under hypoxic conditions, and survival-targeted siRNA transfection decreased the expression of survivin under hypoxic conditions, while co-transfection of survivin-targeted siRNA and HIF-1α-targeted siRNA down-regulated both survivin and HIF-1α expression. Compared with the blank control group, the co-transfected siRNA group exhibited distinct characteristics, with decreased invasion and migration ability, increased apoptosis, and significantly decreased cell proliferation under hypoxic conditions. It was confirmed that the downregulation of survivin and HIF-1α in BGC-823 cells may induce anticancer effects by enhancing apoptosis and decreasing proliferation, migration, and invasion ability. The novelty lies in the application of RNAi technology to silence the expression of both survivin and HIF-1α genes in gastric cancer BGC-823 cells by single and combined interference in an established gastric cancer cell model and observed the mechanism of its effect on the proliferation and apoptosis of gastric cancer cells. Concerning the success of this highly active antiretroviral therapy of gene disruption therapies, which is the first of its kind in the world, we wonder whether we can find other better gene targets for more kinds of tumor therapy.
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Face morphing attacks have become increasingly complex, and existing methods exhibit certain limitations in capturing fine-grained texture and detail changes. To overcome these limitation, in this study, a detection method based on high-frequency features and progressive enhancement learning was proposed. Specifically, in this method, first, high-frequency information are extracted from the three color channels of the image to accurately capture the details and texture changes. Next, a progressive enhancement learning framework was designed to fuse high-frequency information with RGB information. This framework includes self-enhancement and interactive-enhancement modules that progressively enhance features to capture subtle morphing traces. Experiments conducted on the standard database and compared with nine classical technologies revealed that the proposed approach achieved excellent performance.
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As the oasis area in the city, urban park plays an extremely prominent role in the regulation and improvement of the urban ecological environment, especially the local thermal environment, and has become one of the significant ways to reduce the urban heat island (UHI) effect. Our study comprehensively considers the maximum cooling distance and spatial continuity of urban parks, takes 30 parks in Hangzhou, and analyzed their influencing factors to comprehensively explore the park cooling effect. The results showed that the land cover shifted drastically during 2000-2020, and the built-up land area increased greatly, which aggravated the UHI effect. The high UHI value of Hangzhou was concentrated in the city center and presented a spreading trend from north to south. Different types of urban parks presented different cold island effects, with comprehensive parks and ecological parks having the largest cooling area, and community parks exhibit better accumulative cooling effect. In addition, the park's own characteristics (perimeter, area, shape index) and inner and surrounding landscapes were significantly correlated with the park's cooling effect (park cooling area and park cooling efficiency). Our study comprehensively considered the cooling effect of parks from the maximum and accumulative perspectives and provides theoretical and practical guidance for the construction and planning of urban parks, thereby enhancing the well-being of urban residents.
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Calor , Parques Recreativos , Ciudades , Frío , ChinaRESUMEN
A large amount of waste slurry is generated during construction, but direct sedimentation and transportation increase construction costs. Improper treatment leads to ecological and environmental pollution. This paper proposes to reuse drilling waste slurry (DWS) as a raw material from a particular project as a grouting material for the real-time capsule grouting technique (RCG) to replace cement grouting material. This not only deals with DWS but also solves the material demand of RCG. An orthogonal experimental design evaluated the performance of the DWS grouting material (DWS-GM). The five levels for the three factors of this experiment were selected, including the fluidity, bleeding rate, initial setting time, and compression strength. A linear model, support vector machines, and neural networks were used to construct regression models, and the effects of different contents of cement, bentonite, and fly ash on the DWS-GM performance were analyzed. The SVM regression model had better performance in describing the laws of fluidity, bleeding rate, and 28-day compressive strength. Furthermore, the optimization model is proposed to obtain the optimal formulation of the DWS-GM under specific constraints. The optimization results show that the optimal formulation of the DWS-GM was 5.6% cement and 6.9% bentonite. The BL, FL, IST, and 28DCS were 1.61%, 21.87 cm, 27.05 h, and 0.22 MPa to meet the functional requirements of the DWS-GM. The above research fully proves the feasibility of the DWS reuse application. We will further reuse DWS to develop other multifunctional material applications in combination with the control needs of RCG technology and technology from other fields.
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Afterglow luminescence (long persistent luminescence) holds great potential for nonbackground molecular imaging. However, current afterglow probes are mainly nanoparticles, and afterglow imaging systems based on organic small molecules are still lacking and have rarely been reported. Moreover, the lack of reactive sites and a universal molecular scaffold makes it difficult to design activatable afterglow probes. To address these issues, this study reports a novel kind of hemicyanine-based molecule scaffolds with stimuli-responsive afterglow luminescence, which is dependent on an intramolecular cascade photoreaction between 1O2 and the afterglow molecule to store the photoenergy for delayed luminescence after light cessation. As a proof of concept, three modular activatable molecular afterglow probes (MAPs) with a "four-in-one" molecular design by integrating a stimuli-responsive unit, 1O2-generating unit, 1O2-capturing unit, and luminescent unit into one probe are customized for quantification and imaging of targets including pH, superoxide anions, and aminopeptidase. Notably, MAPs show higher sensitivity in afterglow imaging than in fluorescence imaging because the responsive unit simultaneously controls the initiation of fluorescence (S1 to S0) and 1O2 generation (S1 to T1). Finally, MAPs are applied for high-contrast afterglow imaging of drug-induced hepatotoxicity, which is poorly evaluated in clinics and drug discovery. By reporting the sequential occurrence of oxidative stress and upregulation of aminopeptidase, such activatable afterglow probes allow noninvasive imaging of hepatotoxicity earlier than the serological and histology manifestation, indicating their promise for early diagnosis of hepatotoxicity.