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Novel catalysts with multiple active sites and rapid separation are required to effectively activate peroxymonosulfate (PMS) for the removal of organic pollutants from water. Therefore, an integrated catalyst for PMS activation was developed by directly forming Co-Fe Prussian blue analogs on a three-dimensional porous nickel foam (NF), which were subsequently phosphorylated to obtain cobalt-iron bimetallic phosphide (FeCoP@NF). The FeCoP@NF/PMS system efficiently degraded dye wastewater within 20 min. The system exhibited excellent catalytic degradation over a broad pH range and at high dye concentrations due to the presence of unique asymmetrically charged Coa+ and Pb- dual active sites formed by cobalt phosphides within FeCoP@NF. These active sites significantly enhanced the catalytic activity of PMS. The activation mechanism of PMS involves phosphorylation that accelerates electron transfer from FeCoP@NF to PMS, to generate SO4·-, ·OH, O2·-, and 1O2 active species. Three-dimensional FeCoP@NF could be readily recycled and showed good stability for PMS activation. In this study, a highly efficient, stable, and readily recyclable integrated catalyst was developed. This catalyst system effectively resolves the separation and recovery issues associated with conventional powder catalysts and has a wide range of potential applications in wastewater treatment.
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Cobalto , Colorantes , Hierro , Níquel , Peróxidos , Contaminantes Químicos del Agua , Cobalto/química , Níquel/química , Hierro/química , Colorantes/química , Peróxidos/química , Contaminantes Químicos del Agua/química , Catálisis , Fosfinas/químicaRESUMEN
Sulfate radical-based advanced oxidation processes with (SR-AOPs) are widely employed to degrade organic pollutants due to their high efficiency, cost-effectiveness and safety. In this study, a highly active and stable FeNiP was successfully prepared by reduction and heat treatment. FeNiP exhibited high performance of peroxymonosulfate (PMS) activation for tetracycline hydrochloride (TC) removal. Over a wide pH range, an impressive TC degaradation efficiency 97.86% was achieved within 60 min employing 0.1 g/L FeNiP and 0.2 g/L PMS at room temperature. Both free radicals of SO4·-, ·OH, ·O2- and non-free radicals of 1O2 participated the TC degradation in the FeNiP/PMS system. The PMS activation ability was greatly enhanced by the cycling between Ni and Fe bimetal, and the active site regeneration was achieved due to the existence of the negatively charged Pn-. Moreover, the FeNiP/PMS system exhibited substantial TC degradation levels in both simulated real-world disturbance scenarios and practical water tests. Cycling experiments further affirmed the robust stability of FeNiP catalyst, demonstrating sustained degradation efficiency of approximately 80% even after four cycles. These findings illuminate its promising potential across natural water bodies, presenting an innovative catalyst construction approach for PMS activation in the degradation of antibiotic pollutants.
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Hierro , Peróxidos , Tetraciclina , Contaminantes Químicos del Agua , Tetraciclina/química , Contaminantes Químicos del Agua/química , Peróxidos/química , Hierro/química , Níquel/química , Antibacterianos/química , Oxidación-Reducción , Purificación del Agua/métodosRESUMEN
BACKGROUND: A novel automated method for measuring left ventricular (LV) global longitudinal strain (GLS) along the endocardium has advantages in terms of its rapid application and excellent reproducibility. However, it remains unclear whether the available normal range for conventional GLS using the manual method is applicable to the automated GLS method. This study aimed to compare automated GLS head-to-head with manual layer-specific GLS, and to identify whether a specialized normal reference range for automated GLS is needed and explore the main determinants. METHODS: In total, 1683 healthy volunteers (men, 43%; age, 18-80 years) were prospectively enrolled from 55 collaborating laboratories. LV GLS was measured using both manual layer-specific and automated methods. RESULTS: Automated GLS was higher than endocardial, mid-myocardial, and epicardial GLS. Women had a higher automated GLS than men. GLS had no significant age dependency in men, but first increased and then decreased with age in women. Accordingly, sex- and age-specific normal ranges for automated GLS were proposed. Moreover, GLS appeared to have different burdens in relation to dominant determinants between the sexes. GLS in men showed no dominant determinants; however, GLS in women correlated with age, body mass index, and heart rate. CONCLUSIONS: Using the novel automated method, was LV GLS higher than when using the manual GLS method. The normal ranges of automated GLS stratified according to sex and age were provided, with dominant determinants showing sex disparities that require full consideration in clinical practice.
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Ecocardiografía , Tensión Longitudinal Global , Masculino , Humanos , Femenino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Valores de Referencia , Ecocardiografía/métodos , Función Ventricular Izquierda/fisiología , Reproducibilidad de los ResultadosRESUMEN
To achieve the UN Sustainable Development Goals (SDGs) and the China Toilet Revolution on a global scale, it is crucial to implement a decentralized sanitation management system in developing countries. Fecal slags (FS) generated from septic tanks of toilets pose a challenge for remote villages. This study sought to resourcefully utilize FS through co-digesting with food waste (FW) under high-solid anaerobic co-digestion (HSAD). Besides, two metallic nanomaterials, nano-zerovalent iron (nZVI) and magnetite (Fe3O4), were employed to demonstrate the practical improvement of HSAD. The results showed that nZVI-dosed digesters produced the highest cumulative methane of 295.72 mL/gVS, 371.36 mL/gVS, 360.53 mL/gVS and 296.64 mL/gVS in 10%, 15%, 20% and 25% TS content, respectively, which was 1.15, 1.22, 1.16, 1.12 times higher than Fe3O4 dosed digesters. This increment could be ascribed to the simultaneous production of H2 from Fe2+ release from nZVI and the enrichment of homoacetogen. Changes in carbon degradation and methanogenic pathways, which facilitated stability under high TS contents, were observed. At low solid digestion (10% TS), Syntrophomonas cooperated with Methanosarcina and Methanobacterium to metabolize butyrate and propionate. However, due to the buildup of total ammonia nitrogen and volatile fatty acids, acetoclastic methanogens were inhibited in the high-solid digesters (15%, 20% and 25% TS). Consequently, a more resilient and highly tolerant Syntrophaceticus, alongside hydrogenotrophic methanogens such as Methanoculleus and Methanobrevibacter, maintained stability in the harsh environment.
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Nanoestructuras , Eliminación de Residuos , Anaerobiosis , Alimento Perdido y Desperdiciado , Alimentos , Saneamiento , Reactores Biológicos/microbiología , Hierro , Metano , Aguas del AlcantarilladoRESUMEN
Background: Hyperlipidemia is an independent risk factor for kidney injury. Several studies have shown that nicotinamide adenine dinucleotide (NAD+) is an important coenzyme involved in normal body metabolism. Therefore, this study aimed to investigate the possible protective effects of NAD+ against hyperlipidemia-induced kidney injury in apolipoprotein Edeficient (ApoE-/-) mice.
Methods: Twenty-five eight-week-old male ApoE-/- mice were randomly assigned into four groups: normal diet (ND), ND supplemented with NAD+ (ND+NAD+), high-fat diet (HFD), and HFD supplemented with NAD+ (HFD+NAD+). The mice were subjected to their respective diets for a duration of 16 weeks. Blood samples were obtained from the inferior vena cava, collected in serum tubes, and stored at -80°C until use. Kidney tissues was fixed in 10% formalin and then embedded in paraffin for histological evaluation. The remainder of the kidney tissues was snapfrozen in liquid nitrogen for Western blot analysis.
Results: Metabolic parameters (total cholesterol, triglycerides, low-density lipoprotein-cholesterol, creatinine, and blood urea nitrogen) were significantly higher in the HFD group compared to the other groups. Histological analysis revealed prominent pathological manifestations in the kidneys of the HFD group. The HFD+NAD+ group showed increased levels of oxidative stress markers (NRF2 and SOD2) and decreased levels of NOX4 compared to the HFD group. Furthermore, the HFD group exhibited higher levels of TGF-ß, Smad3, Collagen I, Collagen III, Bax, and Bak compared to the other groups. NAD+ supplementation in the HFD+NAD+ group significantly increased the levels of SIRT3, HO-1, Bcl-2, and Bcl-xL compared to the HFD group. Additionally, NF-κB protein expression was higher in the HFD group than in the HFD+NAD+ group.
Conclusion: These findings demonstrated that NAD+ may hold potential as a clinical treatment for kidney injury caused by hyperlipidemia.
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Hiperlipidemias , Ratones , Masculino , Animales , Hiperlipidemias/tratamiento farmacológico , NAD/metabolismo , NAD/uso terapéutico , Ratones Noqueados para ApoE , Riñón/metabolismo , Colesterol/metabolismo , Apolipoproteínas E/genética , Colágeno/metabolismo , Ratones Endogámicos C57BLRESUMEN
OBJECTIVE: To reduce the number of biopsies performed on benign breast lesions categorized as BI-RADS 4-5, we investigated the diagnostic performance of combined two-dimensional and three-dimensional shear wave elastography (2D + 3D SWE) with standard breast ultrasonography (US) for the BI-RADS assessment of breast lesions. METHODS: A total of 897 breast lesions, categorized as BI-RADS 3-5, were subjected to standard breast US and supplemented by 2D SWE only and 2D + 3D SWE analysis. Based on the malignancy rate of less than 2% for BI-RADS 3, lesions assessed by standard breast US were reclassified with SWE assessment. RESULTS: After standard breast US evaluation, 268 (46.1%) participants underwent benign biopsies in BI-RADS 4-5 lesions. By using separated cutoffs for upstaging BI-RADS 3 at 120 kPa and downstaging BI-RADS 4a at 90 kPa in 2D + 3D SWE reclassification, 123 (21.2%) participants underwent benign biopsy, resulting in a 54.1% reduction (123 versus 268). CONCLUSION: Combining 2D + 3D SWE with standard breast US for reclassification of BI-RADS lesions may achieve a reduction in benign biopsies in BI-RADS 4-5 lesions without sacrificing sensitivity unacceptably. CLINICAL RELEVANCE STATEMENT: Combining 2D + 3D SWE with US effectively reduces benign biopsies in breast lesions with categories 4-5, potentially improving diagnostic accuracy of BI-RADS assessment for patients with breast lesions. TRIAL REGISTRATION: ChiCTR1900026556 KEY POINTS: ⢠Reduce benign biopsy is necessary in breast lesions with BI-RADS 4-5 category. ⢠A reduction of 54.1% on benign biopsies in BI-RADS 4-5 lesions was achieved using 2D + 3D SWE reclassification. ⢠Adding 2D + 3D SWE to standard breast US improved the diagnostic performance of BI-RADS assessment on breast lesions: specificity increased from 54 to 79%, and PPV increased from 54 to 71%, with slight loss in sensitivity (97.2% versus 98.7%) and NPV (98.1% versus 98.7%).
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Neoplasias de la Mama , Diagnóstico por Imagen de Elasticidad , Femenino , Humanos , Mama/diagnóstico por imagen , Mama/patología , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Diagnóstico Diferencial , Diagnóstico por Imagen de Elasticidad/métodos , Estudios Prospectivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Ultrasonografía Mamaria/métodosRESUMEN
AIMS: Mitral annular plane systolic excursion (MAPSE) is a simple and reliable index for evaluating left ventricular (LV) systolic function, particularly in patients with poor image quality; however, the lack of reference values limits its widespread use. This study aimed to establish the normal ranges for MAPSE measured using motion-mode (M-mode) and two-dimensional speckle tracking echocardiography (2D-STE) and to explore its principal determinants. METHODS AND RESULTS: This multicentre, prospective, cross-sectional study included 1952 healthy participants [840 men (43%); age range, 18-80 years] from 55 centres. MAPSE was measured using M-mode echocardiography and 2D-STE. The results showed that women had a higher MAPSE than men and MAPSE decreased with age. The age- and sex-specific reference values for MAPSE were established for these two methods. Multiple linear regression analyses revealed that MAPSE on M-mode echocardiography correlated with age and MAPSE on 2D-STE with age, blood pressure (BP), heart rate, and LV volume. Moreover, MAPSE measured by 2D-STE correlated more strongly with global longitudinal strain compared with that measured using M-mode echocardiography. CONCLUSION: Normal MAPSE reference values were established based on age and sex. BP, heart rate, and LV volume are potential factors that influence MAPSE and should be considered in clinical practice. Normal values are useful for evaluating LV longitudinal systolic function, especially in patients with poor image quality, and may further facilitate the use of MAPSE in routine assessments.
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Ecocardiografía , Válvula Mitral , Masculino , Humanos , Femenino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Valores de Referencia , Estudios Prospectivos , Estudios Transversales , Válvula Mitral/diagnóstico por imagen , Ecocardiografía/métodos , Función Ventricular Izquierda/fisiologíaRESUMEN
Objective: Regular check-up with ultrasound in underserved rural and/or remote areas is hampered due to the limited availability of sonologists and ultrasound devices. This study aimed to assess the feasibility and satisfaction of health check-ups with a 5G-based robotic teleultrasound diagnostic system. Methods: In this prospective study, sonologists from two hospitals manipulated the telerobotic ultrasound system to perform teleultrasound check-ups of the liver, gallbladder, pancreas, spleen, kidneys, bladder, prostate (male), uterus and ovaries (female) for the subjects. The feasibility and satisfaction of health check-ups with a 5G-based robotic teleultrasound diagnostic system were evaluated in terms of examination results, examination duration, and satisfaction questionnaire survey. Results: A total of 546 subjects were included with the most frequently diagnosed being abdominal disorders (n = 343) and male reproductive illnesses (n = 97), of which fatty liver (n = 204) and prostatic calcification (n = 54) were the most. The median teleultrasound examination duration (interquartile range) for men and women was 9 (9-11) min and 9 (7-11) min (p = 0.236), respectively. All the subjects were satisfied with this new type of telerobotic ultrasound check-ups and 96% reported no fear of the robotic arm during the examination. Conclusion: The 5G-based teleultrasound robotic diagnostic system in health check-ups is feasible and satisfactory, indicating that this teleultrasound robot system may have significant application value in underserved rural and/or remote areas to mitigate disparity in achieving health equity.
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Procedimientos Quirúrgicos Robotizados , Humanos , Masculino , Femenino , Estudios Prospectivos , Estudios de Factibilidad , Ultrasonografía/métodos , HígadoRESUMEN
The activation of persulfate technology using carbon-based materials doped with heteroatoms has been extensively researched for the elimination of refractory pollutants in wastewater. In this study, metal-organic frameworks were utilized as precursors to synthesize P, N dual-doped carbon material (PNC), which was employed to activate peroxymonosulfate (PMS) for the degradation of tetracycline hydrochloride (TCH). The results demonstrated a 90.2% removal efficiency of total organic carbon within 60 min. The significant increase of surface defects on the nitrogen self-doped porous carbon materials anchored with phosphorus promoted the conversion of superoxide radical to singlet oxygen during PMS activation, which was identified as the key active species of PNC/PMS system. Additionally, the enhanced direct electron transfer also facilitated the degradation of TCH. Consequently, TCH was successfully degraded into nontoxic and harmless inorganic small molecules. The findings of this research provide valuable insights into improving the performance of heteroatom-doped carbon materials for pollutant degradation by activating PMS and transforming the non-radical pathway. The results highlight the potential of metal-organic frameworks derived heteroatoms dual-doped porous carbon catalysts for the development of advanced treatment technologies in wastewater treatment.
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Ultrasound elastography (USE) provides complementary information of tissue stiffness and elasticity to conventional ultrasound imaging. It is noninvasive and free of radiation, and has become a valuable tool to improve diagnostic performance with conventional ultrasound imaging. However, the diagnostic accuracy will be reduced due to high operator-dependence and intra- and inter-observer variability in visual observations of radiologists. Artificial intelligence (AI) has great potential to perform automatic medical image analysis tasks to provide a more objective, accurate and intelligent diagnosis. More recently, the enhanced diagnostic performance of AI applied to USE have been demonstrated for various disease evaluations. This review provides an overview of the basic concepts of USE and AI techniques for clinical radiologists and then introduces the applications of AI in USE imaging that focus on the following anatomical sites: liver, breast, thyroid and other organs for lesion detection and segmentation, machine learning (ML) - assisted classification and prognosis prediction. In addition, the existing challenges and future trends of AI in USE are also discussed.
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Dustbins function as critical infrastructures for urban sanitation, creating a distinct breeding ground for microbial assemblages. However, there is no information regarding the dynamics of microbial communities and the underlying mechanism for community assembly on dustbin surfaces. Here, surface samples were collected from three sampling zones (business building, commercial street and residential community) with different types (kitchen waste, harmful waste, recyclables, and others) and materials (metallic and plastic); and distribution pattern and assembly of microbial communities were investigated by high-throughput sequencing. Bacterial and fungal communities showed the distinct community variations across sampling zones and waste sorting. Core community and biomarker species were significantly correlated with the spatial distribution of overall community. The detection of pathogens highlighted the potential risk of surface microbiome. Human skin, human feces and soil biomes were the potential source environments of the surface microbiomes. Neutral model prediction suggested that microbial community assembly was significantly driven by stochastic processes. Co-association patterns varied with sampling zones and waste types, and neutral amplicon sequence variants (ASVs) that fall within the 95 % confidence intervals of neutral model were largely involved in the stability of microbial networks. These findings improve our understanding of the distribution pattern and the underlying assembly of microbial community on the dustbin surface, thus enabling prospective prediction and assessment of urban microbiomes and their impacts on human health.
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Microbiota , Eliminación de Residuos , Humanos , Consorcios Microbianos , Estudios Prospectivos , Suelo , Procesos EstocásticosRESUMEN
OBJECTIVE: Carotid artery stenting (CAS) has become an alternative strategy to carotid endarterectomy for carotid artery stenosis. Residual stenosis was an independent risk factor for restenosis, with the latter affecting the long-term outcomes of CAS. This multicenter study aimed to evaluate the echogenicity of plaques and hemodynamic alteration by color duplex ultrasound (CDU) examination and investigate their effects on the residual stenosis after CAS. METHODS: From June 2018 to June 2020, 454 patients (386 males and 68 females) with a mean age of 67.2 ± 7.9 years, who underwent CAS from 11 advanced stroke centers in China were enrolled. One week before recanalization, CDU was used to evaluate the responsible plaques, including the morphology (regular or irregular), echogenicity of the plaques (iso-, hypo-, or hyperechoic) and calcification characteristics (without calcification, superficial calcification, inner calcification, and basal calcification). One week after CAS, the alteration of diameter and hemodynamic parameters were evaluated by CDU, and the occurrence and degree of residual stenosis were determined. In addition, magnetic resonance imaging was performed before and during the 30-day postprocedural period to identify new ischemic cerebral lesions. RESULTS: The rate of composite complications, including cerebral hemorrhage, symptomatic new ischemic cerebral lesions, and death after CAS, was 1.54% (7/454 cases). The rate of residual stenosis after CAS was 16.3% (74/454 cases). After CAS, both the diameter and peak systolic velocity (PSV) improved in the preprocedural 50% to 69% and 70% to 99% stenosis groups (P < .05). Compared with the groups without residual stenosis and with <50% residual stenosis, the PSV of all three segments of stent in the 50% to 69% residual stenosis group were the highest, and the difference in the midsegment of stent PSV was the largest (P < .05). Logistic regression analysis showed that preprocedural severe (70% to 99%) stenosis (odds ratio [OR], 9.421; P = .032), hyperechoic plaques (OR, 3.060; P = .006) and plaques with basal calcification (OR, 1.885; P = .049) were independent risk factors for residual stenosis after CAS. CONCLUSIONS: Patients with hyperechoic and calcified plaques of the carotid stenosis are at a high risk of residual stenosis after CAS. CDU is an optimal, simple and noninvasive imaging method to evaluate plaque echogenicity and hemodynamic alterations during the perioperative period of CAS, which can help surgeons to select the optimal strategies and prevent the occurrence of residual stenosis.
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Estenosis Carotídea , Endarterectomía Carotidea , Placa Aterosclerótica , Accidente Cerebrovascular , Masculino , Femenino , Humanos , Persona de Mediana Edad , Anciano , Estenosis Carotídea/complicaciones , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/terapia , Constricción Patológica/etiología , Stents/efectos adversos , Endarterectomía Carotidea/efectos adversos , Accidente Cerebrovascular/epidemiología , Placa Aterosclerótica/complicaciones , Arterias Carótidas/cirugía , Hemodinámica , Resultado del TratamientoRESUMEN
Evidence of the triglyceride-glucose (TyG) index as an independent predictor of arterial stiffness in stage 1 hypertension patients is scarce. This study aimed to explore the association between TyG index and arterial stiffness in this population. A total of 1041 individuals from 32 centers with normal/elevated blood pressure (BP, <130/80 mmHg; 345 men (33%); median age, 37 years) and 585 stage 1 hypertension patients (BP ≥130/80 and <140/90 mmHg; 305 men (52%); median age, 47 years) were prospectively enrolled. Arterial stiffness was determined by measuring carotid ultrafast pulse-wave velocity (ufPWV). TyG index was calculated as ln (fasting triglyceride (TG) × fasting blood glucose/2). Patients with a higher TyG index tended to have higher ufPWV. The TyG index was positively associated with ufPWV at the end of systole in stage 1 hypertension patients after adjusting for confounding factors (ß for per unit .48), and restricted cubic spline analysis confirmed a linear association. Subgroup analyses in terms of age, sex, and body mass index yielded similar results. However, no significant relationship was observed between the TyG index and ufPWV in the population with normal/elevated BP. The fully adjusted ß between ufPWV and the TyG index was higher than the TG/high-density lipoprotein cholesterol ratio, TG, and pulse pressure. In conclusion, patients with a higher TyG index had greater arterial stiffness, and the TyG index independently and positively correlated with arterial stiffness in stage 1 hypertension patients. The TyG index may provide a simple and reliable marker to monitor arterial stiffness in hypertensive patients.
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Hipertensión , Rigidez Vascular , Masculino , Humanos , Adulto , Persona de Mediana Edad , Presión Sanguínea/fisiología , Hipertensión/diagnóstico , Glucosa , Triglicéridos , Rigidez Vascular/fisiología , Glucemia , Factores de Riesgo , BiomarcadoresRESUMEN
Kidney disease is a serious public health problem and various kidney diseases could progress to end-stage renal disease. The many complications of end-stage renal disease. have a significant impact on the physical and mental health of patients. Ultrasound can be the test of choice for evaluating the kidney and perirenal tissue as it is real-time, available and non-radioactive. To overcome substantial interobserver variability in renal ultrasound interpretation, artificial intelligence (AI) has the potential to be a new method to help radiologists make clinical decisions. This review introduces the applications of AI in renal ultrasound, including automatic segmentation of the kidney, measurement of the renal volume, prediction of the kidney function, diagnosis of the kidney diseases. The advantages and disadvantages of the applications will also be presented clinicians to conduct research. Additionally, the challenges and future perspectives of AI are discussed.
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Artificial intelligence (AI), especially deep learning, is gaining extensive attention for its excellent performance in medical image analysis. It can automatically make a quantitative assessment of complex medical images and help doctors to make more accurate diagnoses. In recent years, AI based on ultrasound has been shown to be very helpful in diffuse liver diseases and focal liver lesions, such as analyzing the severity of nonalcoholic fatty liver and the stage of liver fibrosis, identifying benign and malignant liver lesions, predicting the microvascular invasion of hepatocellular carcinoma, curative transarterial chemoembolization effect, and prognoses after thermal ablation. Moreover, AI based on endoscopic ultrasonography has been applied in some gastrointestinal diseases, such as distinguishing gastric mesenchymal tumors, detection of pancreatic cancer and intraductal papillary mucinous neoplasms, and predicting the preoperative tumor deposits in rectal cancer. This review focused on the basic technical knowledge about AI and the clinical application of AI in ultrasound of liver and gastroenterology diseases. Lastly, we discuss the challenges and future perspectives of AI.
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Carcinoma Hepatocelular , Quimioembolización Terapéutica , Gastroenterología , Neoplasias Hepáticas , Humanos , Inteligencia Artificial , Gastroenterología/métodos , Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/métodos , Neoplasias Hepáticas/terapiaRESUMEN
Ternary composite with great modulation of electron transfers has attracted a lot of attention from the field of high-performance room-temperature (RT) gas sensing. Herein, walnut-like WO3-Ni-graphene ternary composites were successfully synthesized by the hydrothermal method for formaldehyde (HCHO) sensing at RT. The structural and morphological analyses were carried out by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). SEM and TEM studies confirmed that walnut-like WO3 nanostructures with an average size of 53 ± 23 nm were functionalized. The Raman and XPS results revealed that, due to the deformation of the O-W-O lattice, surface oxygen vacancies Ov and surface-adsorbed oxygen species Oc were present. The gas-sensing measurement shows that the response of the WO3-Ni-Gr composite (86.8%) was higher than that of the Ni-Gr composite (22.7%) for 500 ppm HCHO at RT. Gas-sensing enhancement can be attributed to a p-n heterojunction formation between WO3 and Ni-Gr, Oc, spill-over effect of Ni decoration, and a special walnut-like structure. Moreover, long term stability (%R = 61.41 ± 1.66) for 30 days and high selectivity in the presence of other gases against HCHO suggested that the proposed sensor could be an ideal candidate for future commercial HCHO-sensing in a real environment.
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The secondary fermentation stage is critical for stabilizing composting products and producing various secondary metabolites. However, the low metabolic rate of mesophilic bacteria is regarded as the rate-limiting stage in composting process. In present study, two indoleacetic acid (IAA)-producing bacteria (Bacillus safensis 33C and Corynebacterium stationis subsp. safensis 29B) were inoculated to strengthen the secondary fermentation stage to improve the plant-growth promoting potential of composting products. The results showed that the addition of IAA-producing bacteria promoted the assimilation of soluble salt, the condensation and aromatization of humus, and the accumulation of dissolved organic nitrogen (DON) and dissolved organic carbon (DOC). The bioaugmentation strategy also enabled faster microbial community succession during the medium-late phase of secondary fermentation. However, the colonization of Bacillus and Corynebacterium could not explain the disproportionate increase of IAA yield, which reached up to 5.6 times compared to the control group. Deeper analysis combined with physicochemical properties and microbial community structure suggested that IAA-producing bacteria might induce the increase of salinity, which enriched halotolerant bacteria capable of producing IAA, such as Halomonas, Brachybacterium and Flavobacterium. In addition, the results also proved that it was necessary to shorten secondary fermentation time to avoid IAA degradation without affecting composting maturity. In summary, enhancing secondary fermentation of composting via adding proper IAA-producing bacteria is an efficient strategy for upgrading the quality of organic fertilizer.
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Compostaje , Bacterias/metabolismo , Fermentación , Fertilizantes , Ácidos Indolacéticos , Estiércol , SueloRESUMEN
The seasonal out-of-limit of manganese ions (Mn2+) in the drinking water reservoirs is an intractable problem to water supply, which can pose a threat to the human health. In this study, the removal of Mn2+ by using pristine (BC), pre-alkali (Pre-BC) and post-alkali (Post-BC) modified biochar originating from rice straw was investigated. The maximum adsorption capacities obtained for BC, Pre-BC, and Post-BC were 20.59, 28.37, and 8.06 mg g-1, respectively. The Langmuir isotherm model and the pseudo-second-order kinetic model were suitable fitting models to describe the adsorption process. The investigation of adsorption functions was carried out that revealed that the predominant forces were precipitation and cation exchange with the proportions of 43.38-69.15% and 38.05-55.79%, respectively. With regard to precipitation, Mn(ii) particles (Al-Si-O-Mn and MnCO3) and insignificantly oxidized insoluble Mn(iv) particles (MnO2) were formed on the biochar surface. Alkali and alkaline earth metals facilitated the behavior of cation exchange, where the primary contributing ions for cation exchange were Na+, Mg2+ and Ca2+ during the adsorption process. These outcomes suggest that alkali pre-treated modification of biochar is practical for the application of manganese pollution control in lakes and reservoirs.