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Crown roots are the main components of root systems in cereals. Elucidating the mechanisms of crown root formation is instrumental for improving nutrient absorption, stress tolerance, and yield in cereal crops. Several members of the WUSCHEL-related homeobox (WOX) and lateral organ boundaries domain (LBD) transcription factor families play essential roles in controlling crown root development in rice (Oryza sativa). However, the functional relationships among these transcription factors in regulating genes involved in crown root development remain unclear. Here, we identified LBD16 as an additional regulator of rice crown root development. We showed that LBD16 is a direct downstream target of WOX11, a key crown root development regulator in rice. Our results indicated that WOX11 enhances LBD16 transcription by binding to its promoter and recruiting its interaction partner JMJ706, a demethylase that removes histone H3 lysine 9 dimethylation (H3K9me2) from the LBD16 locus. In addition, we established that LBD16 interacts with WOX11, thereby impairing JMJ706-WOX11 complex formation and repressing its own transcriptional activity. Together, our results reveal a feedback system regulating genes that orchestrate crown root development in rice, in which LBD16 acts as a molecular rheostat.
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Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Raízes de Plantas , Fatores de Transcrição , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Histona Desmetilases/metabolismo , Histona Desmetilases/genética , Regiões Promotoras Genéticas/genéticaRESUMO
The ubiquitin-proteasome system (UPS), which involves E3 ligases and deubiquitinases (DUBs), is critical for protein homeostasis. The epigenetic reader ZMYND8 (zinc finger MYND-type containing 8) has emerged as an oncoprotein, and its protein levels are elevated in various types of cancer, including breast cancer. However, the mechanism by which ZMYND8 protein levels are increased in cancer remains elusive. Although ZMYND8 has been reported to be regulated by the E3 ligase FBXW7, it is still unknown whether ZMYND8 could be modulated by DUBs. Here, we identified USP7 (ubiquitin carboxyl-terminal hydrolase 7) as a bona fide DUB for ZMYND8. Mechanically, USP7 directly binds to the PBP (PHD-BRD-PWWP) domain of ZMYND8 via its TRAF (tumor necrosis factor receptor-associated factor) domain and UBL (ubiquitin-like) domain and removes F-box and WD repeat domain containing 7 (FBXW7)-catalyzed poly-ubiquitin chains on lysine residue 1034 (K1034) within ZMYND8, thereby stabilizing ZMYND8 and stimulating the transcription of ZMYND8 target genes ZEB1 (zinc finger E-box binding homeobox 1) and VEGFA (Vascular Endothelial Growth Factor A). Consequently, USP7 enhances the capacity of breast cancer cells for migration and invasion through antagonizing FBXW7-mediated ZMYND8 degradation. Importantly, the protein levels of USP7 positively correlates with those of ZMYND8 in breast cancer tissues. These findings delineate an important layer of migration and invasion regulation by the USP7-ZMYND8 axis in breast cancer cells.
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Pneumocystis pneumonia (PCP) is a fungal pulmonary disease with high mortality in immunocompromised patients. Neutrophils are essential in defending against fungal infections; however, their role in PCP is controversial. Here we aim to investigate the effects of neutrophil extracellular traps (NETs) on Pneumocystis clearance and lung injury using a mouse model of PCP. Intriguingly, although neutrophils play a fundamental role in defending against fungal infections, NETs failed to eliminate Pneumocystis, but instead impaired the killing of Pneumocystis. Mechanically, Pneumocystis triggered Leukotriene B4 (LTB4)-dependent neutrophil swarming, leading to agglutinative NET formation. Blocking Leukotriene B4 with its receptor antagonist Etalocib significantly reduced the accumulation and NET release of neutrophils in vitro and in vivo, enhanced the killing ability of neutrophils against Pneumocystis, and alleviated lung injury in PCP mice. This study identifies the deleterious role of agglutinative NETs in Pneumocystis infection and reveals a new way to prevent NET formation, which provides new insights into the pathogenesis of PCP.
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Armadilhas Extracelulares , Leucotrieno B4 , Neutrófilos , Pneumocystis , Pneumonia por Pneumocystis , Armadilhas Extracelulares/imunologia , Animais , Camundongos , Neutrófilos/imunologia , Pneumonia por Pneumocystis/imunologia , Leucotrieno B4/metabolismo , Leucotrieno B4/imunologia , Pneumocystis/imunologia , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , HumanosRESUMO
Magic-angle twisted bilayer graphene exhibits correlated phenomena such as superconductivity and Mott insulating states related to the weakly dispersing flat band near the Fermi energy. Such a flat band is expected to be sensitive to both the moiré period and lattice relaxations. Thus, clarifying the evolution of the electronic structure with the twist angle is critical for understanding the physics of magic-angle twisted bilayer graphene. Here we combine nano-spot angle-resolved photoemission spectroscopy and atomic force microscopy to resolve the fine electronic structure of the flat band and remote bands, as well as their evolution with twist angle from 1.07° to 2.60°. Near the magic angle, the dispersion is characterized by a flat band near the Fermi energy with a strongly reduced band width. Moreover, we observe a spectral weight transfer between remote bands at higher binding energy, which allows to extract the modulated interlayer spacing near the magic angle. Our work provides direct spectroscopic information on flat band physics and highlights the important role of lattice relaxations.
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Changing ambient temperature often impairs plant development and sexual reproduction, particularly pollen ontogenesis. However, mechanisms underlying cold stress-induced male sterility are not well understood. Here, we exposed Chinese cabbage (Brassica campestris) to different cold conditions during flowering and demonstrated that the tetrad stage was the most sensitive. After completion of pollen development at optimal conditions, transient cold stress at the tetrad stage still impacted auxin levels, starch and lipid accumulation, and pollen germination, ultimately resulting in partial male sterility. Transcriptome and metabolome analyses and histochemical staining indicated that the reduced pollen germination rate was due to the imbalance of energy metabolism during pollen maturation. The investigation of ß-glucuronidase (GUS)-overexpressing transgenic plants driven by the promoter of DR5 (DR5::GUS report system) combined with cell tissue staining and metabolome analysis further validated that cold stress during the tetrad stage reduced auxin levels in mature pollen grains. Low-concentration auxin treatment on floral buds at the tetrad stage before cold exposure improved the cold tolerance of mature pollen grains. Artificially changing the content of endogenous auxin during pollen maturation by spraying chemical reagents and loss-of-function investigation of the auxin biosynthesis gene YUCCA6 by artificial microRNA technology showed that starch overaccumulation severely reduced the pollen germination rate. In summary, we revealed that transient cold stress at the tetrad stage of pollen development in Chinese cabbage causes auxin-mediated starch-related energy metabolism imbalance that contributes to the decline in pollen germination rate and ultimately seed set.
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Brassica , Metabolismo Energético , Ácidos Indolacéticos , Pólen , Pólen/efeitos dos fármacos , Pólen/genética , Pólen/fisiologia , Pólen/crescimento & desenvolvimento , Ácidos Indolacéticos/metabolismo , Metabolismo Energético/efeitos dos fármacos , Brassica/genética , Brassica/fisiologia , Brassica/metabolismo , Brassica/efeitos dos fármacos , Resposta ao Choque Frio/fisiologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Plantas Geneticamente Modificadas , Temperatura Baixa , Germinação/efeitos dos fármacosRESUMO
Moiré superlattices have become a fertile playground for topological Chern insulators, where the displacement field can tune the quantum geometry and Chern number of the topological band. However, in experiments, displacement field engineering of spontaneous symmetry-breaking Chern bands has not been demonstrated. Here in a rhombohedral trilayer graphene moiré superlattice, we use a thermodynamic probe and transport measurement to monitor the Chern number evolution as a function of the displacement field. At a quarter filling of the moiré band, a novel Chern number of three is unveiled to compete with the well-established number of two upon turning on the electric field and survives when the displacement field is sufficiently strong. The transition can be reconciled by a nematic instability on the Fermi surface due to the pseudomagnetic vector field potentials associated with moiré strain patterns. Our work opens more opportunities to active control of Chern numbers in van der Waals moiré systems.
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Prostatitis represents a common disease of the male genitourinary system, significantly impacting the physical and mental health of male patients. While numerous studies have suggested a potential link between immune cell activity and prostatitis, the exact causal role of immune cells in prostatitis remains uncertain. This study aims to explore the causal relationship between immune cell characteristics and prostatitis using a bidirectional Mendelian randomization approach. This study utilizes data from the public GWAS database and employs bidirectional Mendelian randomization analysis to investigate the causal relationship between immune cells and prostatitis. The causal relationship between 731 immune cell features and prostatitis was primarily investigated through inverse variance weighting (IVW), complemented by MR-Egger regression, a simple model, the weighted median method, and a weighted model. Ultimately, the results underwent sensitivity analysis to assess the heterogeneity, horizontal pleiotropy, and stability of Single Nucleotide Polymorphisms (SNPs) in immune cells and prostatitis. MR analysis revealed 17 immune cells exhibiting significant causal effects on prostatitis. In contrast, findings from reverse MR indicated a significant causal relationship between prostatitis and 13 immune cells. Our study utilizes bidirectional Mendelian Randomization to establish causal relationships between specific immune cell phenotypes and prostatitis, highlighting the reciprocal influence between immune system behavior and the disease. Our findings suggest targeted therapeutic approaches and the importance of including diverse populations for broader validation and personalized treatment strategies.
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Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Prostatite , Masculino , Humanos , Prostatite/genética , Prostatite/imunologia , Predisposição Genética para DoençaRESUMO
This study was to explore the role of ELOVL6 in the development of head and neck squamous cell carcinoma (HNSCC). Considering its previously identified oncogenic role in hepatocellular carcinoma. ELOVL6 gene expression, clinicopathological analysis, enrichment analysis, and immune infiltration analysis were based on the data from Gene Expression Omnibus and The Cancer Genome Atlas, with additional bioinformatics analyses performed. Human HNSCC tissue microarray and cell lines were used. The expression of ELOVL6 in HNSCC was detected by quantitative polymerase chain reaction, immunohistochemistry assay, and western blot analysis. The proliferation ability of HNSCC cells, invasion, and apoptosis were evaluated using cell counting kit-8 method, Transwell assay, and flow cytometry, respectively. Based on the data derived from the cancer databases and our HNSCC cell and tissue studies, we found that ELOVL6 was overexpressed in HNSCC. Moreover, ELOVL6 expression level had a positive correlation with clinicopathology of HNSCC. Gene set enrichment analysis showed that ELOVL6 affected the occurrence of HNSCC through WNT signaling pathway. Functional experiments demonstrated that ELOVL6 knockdown inhibited the proliferation and invasion of HNSCC cells while promoting apoptosis. Additionally, compound 3f, an agonist of WNT/ß-catenin signaling pathway, enhances the effect of ELOVL6 on the progression of HNSCC cells. ELOVL6 is upregulated in HNSCC and promotes the development of HNSCC cells by inducing WNT/ß-catenin signaling pathway. ELOVL6 stands a potential target for the treatment of HNSCC and a prognosis indicator of human HNSCC.
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Elongases de Ácidos Graxos , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas de Cabeça e Pescoço , Via de Sinalização Wnt , Feminino , Humanos , Masculino , Apoptose , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Elongases de Ácidos Graxos/genética , Elongases de Ácidos Graxos/metabolismo , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/metabolismo , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Via de Sinalização Wnt/genéticaRESUMO
This work demonstrates a high-performance photodetector with a 4-cycle Ge0.86Si0.14/Ge multi-quantum well (MQW) structure grown by reduced pressure chemical vapor deposition techniques on a Ge-buffered Si (100) substrate. At -1â V bias, the dark current density of the fabricated PIN mesa devices is as low as 3â mA/cm2, and the optical responsivities are 0.51 and 0.17â A/W at 1310 and 1550â nm, respectively, corresponding to the cutoff wavelength of 1620â nm. At the same time, the device has good high-power performance and continuous repeatable light response. On the other hand, the temperature coefficient of resistance (TCR) of the device is as high as -5.18%/K, surpassing all commercial thermal detectors. These results indicate that the CMOS-compatible and low-cost Ge0.86Si0.14/Ge multilayer structure is promising for short-wave infrared and uncooled infrared imaging.
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Electrons residing in a flat-band system can play a vital role in triggering spectacular phenomenology due to relatively large interactions and spontaneous breaking of different degeneracies. In this work, we demonstrate chirally twisted triple bilayer graphene, a new moiré structure formed by three pieces of helically stacked Bernal bilayer graphene, as a highly tunable flat-band system. In addition to the correlated insulators showing at integer moiré fillings, commonly attributed to interaction induced symmetry broken isospin flavors in graphene, we observe abundant insulating states at half-integer moiré fillings, suggesting a longer-range interaction and the formation of charge density wave insulators which spontaneously break the moiré translation symmetry. With weak out-of-plane magnetic field applied, as observed half-integer filling states are enhanced and more quarter-integer filling states appear, pointing toward further quadrupling moiré unit cells. The insulating states at fractional fillings combined with Hartree-Fock calculations demonstrate the observation of a new type of correlated charge density wave insulators in graphene and points to a new accessible twist manner engineering correlated moiré electronics.
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PURPOSE: This updated umbrella review aimed to evaluate the evidence regarding the associations between dietary factors and the risks of esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC). METHODS: The PubMed, Embase, Cochrane Library, and Web of Science databases were searched to identify relevant studies. The quality of the included meta-analyses was evaluated using A MeaSurement Tool to Assess systematic Reviews 2 (AMSTAR 2). For each association, the number of cases, random effects pooled effect size, 95% confidence intervals (CIs), heterogeneity, 95% prediction interval (PrI), small-study effect, and excess significance bias were recalculated to determine the evidence level. RESULTS: We identified 33 meta-analyses describing 58 dietary factors associated with ESCC and 29 meta-analyses describing 38 dietary factors associated with EAC. There was convincing evidence regarding the association of 2 dietary factors (areca nut and high alcohol) with the risk of ESCC. There was highly suggestive evidence regarding the association of only 1 dietary factor (healthy pattern) with the risk of ESCC. There was suggestive evidence regarding the association of 11 dietary factors with the risk of ESCC, including fruit, citrus fruit, vegetables, pickled vegetables, maté tea, moderate alcohol, hot beverages and foods, hot tea, salt, folate, and vitamin B6. There was convincing evidence regarding the association of one dietary factor (vitamin B6) with the risk of EAC. There was suggestive evidence regarding the association of 4 dietary factors with the risk of EAC, including processed meat, dietary fibre, carbohydrate, and vitamin B12. The convincing evidence regarding the associations between dietary factors and the risks of ESCC and EAC remained robust in sensitivity analyses. CONCLUSIONS: This umbrella review highlighted convincing evidence regarding the associations of areca nut and high alcohol with a higher risk of ESCC. Additionally, an association between vitamin B6 and a decreased risk of EAC was observed. Further research is needed to examine the dietary factors with weak evidence regarding their associations with ESCC and EAC.
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Adenocarcinoma , Dieta , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/etiologia , Dieta/métodos , Dieta/estatística & dados numéricos , Dieta/efeitos adversos , Adenocarcinoma/etiologia , Adenocarcinoma/epidemiologia , Carcinoma de Células Escamosas do Esôfago/epidemiologia , Carcinoma de Células Escamosas do Esôfago/etiologia , Fatores de Risco , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/etiologiaRESUMO
Polyvinyl chloride (PVC) waste plastic is a typical solid waste. In this paper, the dechlorination and carbonization behavior of PVC in ethanol-water/water system under different process parameters (temperature, residence time, solid-liquid ratio) was studied, and hydrothermal carbon was characterized by SEM, elemental analysis, TG-DTG, XPS, Py-GC/MS. The results show that temperature is the key to the hydrothermal dechlorination of PVC, and the dechlorination efficiency of PVC is the highest by parameter optimization (220°C-90 min-10% S/D-80% E/D), which can reach 96.33 %. With the removal of Cl, the surface of the PVC matrix changed from full and smooth flocculent to honeycomb with uniform pore size distribution. Thermogravimetric analysis shows that the combustion of hydrochar can be divided into three stages: HCl precipitation and volatile combustion, semi-coke and coke combustion, and fixed carbon combustion. The combustion parameters and kinetic parameters of hydrochar were measured, and it was found that the hydrothermal carbonization of PVC at higher temperatures and ethanol-water ratio could improve the combustion performance of hydrochar. The highest calorific value can reach 36.68 MJ/mol. Py-GC/MS analyzed the distribution of the pyrolysis products, and alkylbenzene and aliphatic were the main products of pyrolysis. The structural analysis of hydrochar showed that C-C and CC accounted for the largest proportion, accompanied by a small amount of C-O and CO and trace C-Cl. The possible reaction mechanism of the hydrothermal carbonization of PVC was analyzed based on the distribution of functional groups and compound composition. This work provides an effective and sustainable method for the recycling of refractory chlorinated plastics.
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Coque , Cloreto de Polivinila , Cloreto de Polivinila/química , Água , Temperatura , CarbonoRESUMO
The performance of Electro-Fenton (EF) cathode materials is primarily assessed by H2O2 yield and Fe3+ reduction efficiency. This study explores the impact of pore structure in chitin-based porous carbon on EF cathode effectiveness. We fabricated mesoporous carbon (CPC-700-2) and microporous carbon (ZPC-700-3) using template and activation methods, retaining nitrogen from the precursors. CPC-700-2, with mesopores (3-5 nm), enhanced O2 diffusion and oxygen reduction, producing up to 778 mg/L of H2O2 in 90 min. ZPC-700-3, with a specific surface area of 1059.83 m2/g, facilitated electron transport and ion diffusion, achieving a Fe2+/Fe3+ conversion rate of 79.9%. EF systems employing CPC-700-2 or ZPC-700-3 as the cathode exhibited superior degradation performance, achieving 99% degradation of Rhodamine B, efficient degradation, and noticeable decolorization. This study provides a reference for the preparation of functionalized carbon cathode materials for efficient H2O2 production and effective Fe3+ reduction in EF systems.
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PURPOSE: Dentin hypersensitivity (DH) is a prevalent condition, but long-term effective treatments are scarce. Differentiation of odontoblast-like cells is promising for inducing tertiary dentinogenesis and ensuring sustained therapeutic efficacy against DH. This study examined the effects and mechanism of action of mild heat stress (MHS) on the differentiation of odontoblast-like MDPC-23 cells. METHODS: We used a heating device to accurately control the temperature and duration, mimicking the thermal microenvironment of odontoblast-like cells. Using this device, the effects of MHS on cell viability and differentiation were examined. Cell viability was assessed using the MTT assay. The expression and nucleoplasmic ratio of the yes-associated protein (YAP) were examined by western blotting and immunofluorescence. The gene expression levels of heat shock proteins (HSPs) and dentin matrix protein-1 (DMP1) were measured using qPCR. Dentin sialophosphoprotein (DSPP) expression was evaluated using immunofluorescence and immunoblotting. Verteporfin was used to inhibit YAP activity. RESULTS: Mild heat stress (MHS) enhanced the odontoblast differentiation of MDPC-23 cells while maintaining cell viability. MHS also increased YAP activity, as well as the levels of HSP25 mRNA, HSP70 mRNA, HSP90α mRNA, DMP1 mRNA, and DSPP protein. However, after YAP inhibition, both cell viability and the levels of HSP90α mRNA, DMP1 mRNA, and DSPP protein were reduced. CONCLUSION: YAP plays a crucial role in maintaining cell viability and promoting odontoblast differentiation of MDPC-23 cells under MHS. Consequently, MHS is a potential therapeutic strategy for DH, and boosting YAP activity could be beneficial for maintaining cell viability and promoting odontoblast differentiation.
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Diferenciação Celular , Resposta ao Choque Térmico , Odontoblastos , Proteínas de Sinalização YAP , Odontoblastos/metabolismo , Animais , Proteínas de Sinalização YAP/metabolismo , Camundongos , Linhagem Celular , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Sobrevivência CelularRESUMO
Short-term exposure to air pollution has previously been studied in relation to certain neurological disorders, but there is still a lack of convincing data linking air pollution to epileptic seizures. The study's goal was to investigate how exposure to ambient nitrogen dioxide (NO2) affected the number of patients seeking assistance at the Wuhan Emergency Medical Center due to epileptic seizures. We gathered data on medical emergency calls (MECs), daily ambient air pollution concentrations (SO2, NO2, PM2.5, PM10, CO, and O3), and meteorological variables in Wuhan, China, spanning from January 1, 2017, to November 30, 2019. To investigate the potential influence of ambient nitrogen dioxide on MECs for epileptic seizures, we carried out a time-series investigation using the general additive model (GAM). Additionally, analyses stratified by season, age, and gender were performed. A total of 8989 records of MECs for epileptic seizures were enrolled in our study during the period. Statistical analysis indicates that a rise of 10 µg/m3 in NO2 concentration is linked to a 0.17% increase in daily MECs for epileptic seizures (95% confidence interval [CI]: 0.02%, 0.32%). Furthermore, people aged 14-59 years were more susceptible(2.25%, P < 0.05). The short-term effects of NO2 exposure on daily MECs for epileptic seizures were stronger in warm seasons than in cool seasons (0.55% vs. -0.10%, P < 0.0001). Our findings suggests that short-term exposure to ambient NO2 was positively correlated with daily MECs for epileptic seizures in Wuhan, China. Additionally, we observed that these associations were stronger in patients aged above 14 but under 60 years and the warmer seasons (from April to September).
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"Left-behind" children refer to those who live in rural areas but have parents migrating to urban areas for work. They are at increased risk for developmental problems and family dysfunction. However, we currently know little regarding their support systems at school. Using daily data over five school days from 90 adolescents (Mage = 13.70) in rural China, this study investigated daily associations linking teacher and peer support to school belonging, and how these associations varied by parental migration. Teacher but not peer support was positively associated with same-day school belonging. However, this association was attenuated for adolescents with longer duration and history of parental migration. The findings highlighted the importance of considering school settings and within-group variations for left-behind adolescents.
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Sludge from wastewater treatment processes with high water content and large volume has become an inevitable issue in environmental management. Due to the challenging dewatering properties of sludge, current mechanical dewatering methods are no longer sufficient to meet the escalating water content standards of sludge. This paper summarizes the characteristics of various sludge and raises reasons for the their dewaterability differences. Affected by extracellular polymeric substances, biological sludge is hydrophilic and negatively charged, which limits the dewatering degree. The rheological properties, flocs, ionic composition, and solid phase concentration of the sludge also influence the dewatering to some extent. For these factors, the chemical conditioning measures with simple operation and excellent effect improve its dewaterability, which mainly include flocculation/coagulation, acid/alkali treatment, advanced oxidation, surfactant treatment and combined treatment. There is a growing necessity to explore the development of new chemical conditioning agents, even though traditional agents continue to remain widely used. However, the development of these new agents should prioritize finding a balance between various factors such as efficiency, effectiveness, ease of operation, environmental safety, and cost-effectiveness. Electrochemical dewatering enhances solid-liquid separation, and its coupling with chemical conditioning is also an excellent means to further reduce water content. In addition, the improvement of press filter is an effective way, which is influenced by pressure, processing time, sludge cake thickness and pore structure, filter media etc. In general, it is essential to develop new conditioning agents and enhance mechanical filtration press technology based on a thorough understanding of various sludge properties. Concurrently, an in-depth study of the principles of mechanical pressure filtration will contribute to establishing a theoretical foundation for effective deep sludge dewatering and propel further advancements in this field.
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Esgotos , Água , Esgotos/química , Água/química , Filtração , Floculação , Pressão , Eliminação de Resíduos Líquidos/métodosRESUMO
In this study, the process conditions, physicochemical properties, structural composition and activity of polysaccharides isolated from leechee peel (LPP) by ultrasound-assisted extraction (UAE) with enzyme and alkali solution extraction (ASE) were compared. The results showed that the total sugar content of LPP extracted by UAE accounted for 75.65 %, which was significantly higher than that extracted by alkali solution. The optimum conditions were as follows: extraction temperature of 68.78 â, ultrasonic enzymolysis time of 39.68 min, pectinase dosage of 4.03 %, solid-liquid ratio of 1:30 g/mL, and ultrasonic power of 360 W. The antioxidant activities and structure of leechee peel polysaccharide (LPP) prepared under different conditions were compared. It was found that UAE-LPP was an α-type polysaccharide containing 15.83 % uronic acid. Moreover, LPP extracted by UAE showed strong activity in anti-lipid peroxidation and reducing ability. Ultrasound-assisted enzymatic method is an effective means to improve the content and activity of natural plant polysaccharides, and this method has the advantages of short time-consuming, simple process and easy operation, which can greatly improve the utilization rate of polysaccharides and lay a theoretical and scientific basis for the development and utilization of LPP.
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Antioxidantes , Fracionamento Químico , Polissacarídeos , Ondas Ultrassônicas , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Fracionamento Químico/métodos , Antioxidantes/química , Antioxidantes/isolamento & purificação , Poligalacturonase , Temperatura , Peroxidação de Lipídeos/efeitos dos fármacosRESUMO
BACKGROUND: Chronic hepatitis B (CHB) imposes substantial economic and social burdens globally. The management of CHB involves intricate monitoring and adherence challenges, particularly in regions like China, where a high prevalence of CHB intersects with health care resource limitations. This study explores the potential of ChatGPT-3.5, an emerging artificial intelligence (AI) assistant, to address these complexities. With notable capabilities in medical education and practice, ChatGPT-3.5's role is examined in managing CHB, particularly in regions with distinct health care landscapes. OBJECTIVE: This study aimed to uncover insights into ChatGPT-3.5's potential and limitations in delivering personalized medical consultation assistance for CHB patients across diverse linguistic contexts. METHODS: Questions sourced from published guidelines, online CHB communities, and search engines in English and Chinese were refined, translated, and compiled into 96 inquiries. Subsequently, these questions were presented to both ChatGPT-3.5 and ChatGPT-4.0 in independent dialogues. The responses were then evaluated by senior physicians, focusing on informativeness, emotional management, consistency across repeated inquiries, and cautionary statements regarding medical advice. Additionally, a true-or-false questionnaire was employed to further discern the variance in information accuracy for closed questions between ChatGPT-3.5 and ChatGPT-4.0. RESULTS: Over half of the responses (228/370, 61.6%) from ChatGPT-3.5 were considered comprehensive. In contrast, ChatGPT-4.0 exhibited a higher percentage at 74.5% (172/222; P<.001). Notably, superior performance was evident in English, particularly in terms of informativeness and consistency across repeated queries. However, deficiencies were identified in emotional management guidance, with only 3.2% (6/186) in ChatGPT-3.5 and 8.1% (15/154) in ChatGPT-4.0 (P=.04). ChatGPT-3.5 included a disclaimer in 10.8% (24/222) of responses, while ChatGPT-4.0 included a disclaimer in 13.1% (29/222) of responses (P=.46). When responding to true-or-false questions, ChatGPT-4.0 achieved an accuracy rate of 93.3% (168/180), significantly surpassing ChatGPT-3.5's accuracy rate of 65.0% (117/180) (P<.001). CONCLUSIONS: In this study, ChatGPT demonstrated basic capabilities as a medical consultation assistant for CHB management. The choice of working language for ChatGPT-3.5 was considered a potential factor influencing its performance, particularly in the use of terminology and colloquial language, and this potentially affects its applicability within specific target populations. However, as an updated model, ChatGPT-4.0 exhibits improved information processing capabilities, overcoming the language impact on information accuracy. This suggests that the implications of model advancement on applications need to be considered when selecting large language models as medical consultation assistants. Given that both models performed inadequately in emotional guidance management, this study highlights the importance of providing specific language training and emotional management strategies when deploying ChatGPT for medical purposes. Furthermore, the tendency of these models to use disclaimers in conversations should be further investigated to understand the impact on patients' experiences in practical applications.