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1.
Materials (Basel) ; 17(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38612080

RESUMO

A heat recovery coke oven (HRCO) is one of important approaches to achieving a carbon peak and carbon neutrality in China. However, the steady operation of an HRCO is significantly influenced by the internal working conditions and the quality of lining refractories. In this work, a comprehensive study of the internal working conditions of an HRCO was carried out. The results suggest that the partition wall (PW) between the carbonization and combustion chambers is the most vulnerable area, with the corresponding traditional silica bricks inadequate for the service requirements. A reference based on a comparison of the average thermal stress and high-temperature compressive strength is offered for evaluating and selecting silica bricks for the PW. New optimized silica bricks within the reference are verified to be more applicable to the actual working conditions of an HRCO than the traditional silica bricks. As such, this work provides valuable guidance for the optimization and selection of silica bricks for the PW in an HRCO.

2.
J Imaging Inform Med ; 37(4): 1874-1888, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38478188

RESUMO

U-Net has demonstrated strong performance in the field of medical image segmentation and has been adapted into various variants to cater to a wide range of applications. However, these variants primarily focus on enhancing the model's feature extraction capabilities, often resulting in increased parameters and floating point operations (Flops). In this paper, we propose GA-UNet (Ghost and Attention U-Net), a lightweight U-Net for medical image segmentation. GA-UNet consists mainly of lightweight GhostV2 bottlenecks that reduce redundant information and Convolutional Block Attention Modules that capture key features. We evaluate our model on four datasets, including CVC-ClinicDB, 2018 Data Science Bowl, ISIC-2018, and BraTS 2018 low-grade gliomas (LGG). Experimental results show that GA-UNet outperforms other state-of-the-art (SOTA) models, achieving an F1-score of 0.934 and a mean Intersection over Union (mIoU) of 0.882 on CVC-ClinicDB, an F1-score of 0.922 and a mIoU of 0.860 on the 2018 Data Science Bowl, an F1-score of 0.896 and a mIoU of 0.825 on ISIC-2018, and an F1-score of 0.896 and a mIoU of 0.853 on BraTS 2018 LGG. Additionally, GA-UNet has fewer parameters (2.18M) and lower Flops (4.45G) than other SOTA models, which further demonstrates the superiority of our model.


Assuntos
Glioma , Processamento de Imagem Assistida por Computador , Humanos , Processamento de Imagem Assistida por Computador/métodos , Glioma/diagnóstico por imagem , Glioma/patologia , Algoritmos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Redes Neurais de Computação , Bases de Dados Factuais , Imageamento por Ressonância Magnética
3.
Physiol Plant ; 176(1): e14197, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38344855

RESUMO

Increased acid phosphatase (APase) activity is a prominent feature of tomato (Solanum lycopersicum) responses to inorganic phosphate (Pi) restriction. SlPHL1, a phosphate starvation response (PHR) transcription factor, has been identified as a positive regulator of low Pi (LP)-induced APase activity in tomato. However, the molecular mechanism underlying this regulation remains to be elucidated. Here, SlPHL1 was found to positively regulate the LP-induced expression of five potential purple acid phosphatase (PAP) genes, namely SlPAP7, SlPAP10b, SlPAP12, SlPAP15, and SlPAP17b. Furthermore, we provide evidence that SlPHL1 can stimulate transcription of these five genes by binding directly to the PHR1 binding sequence (P1BS) located on their promoters. The P1BS mutation notably weakened SlPHL1 binding to the promoters of SlPAP7, SlPAP12, and SlPAP17b but almost completely abolished SlPHL1 binding to the promoters of SlPAP10b and SlPAP15. As a result, the transcriptional activation of SlPHL1 on SlPAP10b and SlPAP15 was substantially diminished. In addition, not only did transient overexpression of either SlPAP10b or SlPAP15 in tobacco leaves increase APase activity, but overexpression of SlPAP15 in Arabidopsis and tomato also increased APase activity and promoted plant growth. Subsequently, two SPX proteins, SlSPX1 and SlSPX4, were shown to physically interact with SlPHL1. Moreover, SlSPX1 inhibited the transcriptional activation of SlPHL1 on SlPAP10b and SlPAP15 and negatively regulated the activity of APase. Taken together, these results demonstrate that SlPHL1-mediated LP signaling promotes APase activity by activating the transcription of SlPAP10b and SlPAP15, which may provide valuable insights into the mechanisms of tomato response to Pi-limited stress.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Solanum lycopersicum , Fosfatos , Solanum lycopersicum/genética , Fatores de Transcrição/metabolismo , Arabidopsis/metabolismo , Fosfatase Ácida/genética , Fosfatase Ácida/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Arabidopsis/metabolismo
4.
Dev Comp Immunol ; 149: 105059, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37722630

RESUMO

In mammals, right open reading frame kinase 3 (RIOK3) is related with cancer development and immune regulation. To explore the role of teleost RIOK3 in the antiviral innate immunity, the homolog of RIOK3 (bcRIOK3) from black carp (Mylopharyngodon piceus) has been cloned and characterized in this study. Sequence analysis revealed that bcRIOK3 is conserved in vertebrates. The transcription of bcRIOK3 varied in host cells in response to the stimulation of spring viremia of carp virus (SVCV), poly (I:C), and LPS. Immunoblotting (IB) and immunofluorescence (IF) assays identified bcRIOK3 as a cytoplasmic protein with a molecular weight of ∼60 kDa. It was interesting that bcRIOK3 knockdown led to the decreased basal mRNA levels of IFNa, IFNb and Viperin; however, triggered obviously higher mRNA levels of the above genes after viral infection and enhanced host resistance to SVCV. Like its mammalian counterpart, bcRIOK3 overexpression in EPC cells showed a significant inhibitory effect on black carp MDA5 (bcMDA5)-mediated transcription of interferon promoters and antiviral activity. Co-immunoprecipitation and immunofluorescent assays identified the association between bcRIOK3 and bcMDA5. Further analysis revealed that bcRIOK3 enhanced the K48-linked ubiquitination and proteasome-dependent degradation of bcMDA5, and it weakened the oligomerization of bcMDA5 under poly (I:C) stimulation. In summary, our data conclude that RIOK3 dampens MDA5-mediated IFN signaling by promoting its degradation in black carp, which provide new insights into the regulation of IFN signaling in teleost.


Assuntos
Carpas , Doenças dos Peixes , Infecções por Reoviridae , Reoviridae , Infecções por Rhabdoviridae , Rhabdoviridae , Animais , Humanos , Carpas/metabolismo , Rhabdoviridae/fisiologia , Reoviridae/fisiologia , Antivirais , Imunidade Inata/genética , Poli I-C/farmacologia , RNA Mensageiro/genética , Proteínas de Peixes/metabolismo , Mamíferos/genética
5.
Front Neurosci ; 17: 1106214, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37274200

RESUMO

Objective: Anti-contactin-associated protein 2 (CASPR2)-related autoimmune encephalitis (AE) is more common in adults than in children. Clinical understanding of anti-CASPR2-antibody (Ab)-related AE, diagnosis and treatment standards are lacking in children. Therefore, this retrospective study on clinical symptoms and treatment outcomes in children with anti-CASPR2-Ab-related AE was conducted, to improve the clinical understanding of the disease, its diagnosis and treatment. Methods: This study retrospectively assessed children with anti-CASPR2-Ab-related AE from January 1, 2020, to June 30, 2022, in the Department of Neurology at Hunan Children's Hospital. Data regarding demographics, clinical symptoms, laboratory examinations, electroencephalography (EEG), imaging, and curative were collected. Results: Thirteen patients were positive for serum anti-CASPR2-Ab (age at manifestation, 25 months to 13 years old; median, 8.1 years old; male-to-female ratio, 8/5). One patient (P1) had dual Abs, including anti-CASPR2 and anti-N-methyl-D-aspartate receptor Abs; his symptoms were more severe than those of children with anti-CASPR2 Abs alone. The clinical symptoms of the 13 patients with anti-CASPR2 Ab were movement disorders (9/13), consciousness disorders (9/13), abnormal demeanor (8/13), seizures (7/13), language disorders (6/13), fever (6/13), pain (4/13), involuntary exercise (4/13), poor diet (4/13), vomiting (3/13), sleep disorders (3/13), mood disorders (3/13), eczema/itching/redness (2/13), sweating (P8), urinary disorders (P13), and cognitive disorders (P9). No tumors were found in any patient. Additionally, EEG results of six patients were abnormal and imaging findings such as abnormal signals were found in 10 patients. Moreover, all except one patient recovered well after treatment; P1 with overlapping syndrome underwent recovery for more than 2 years. None of the patients who recovered have had a relapse. Discussion and conclusion: Anti-CASPR2-Ab-related AE has several clinical manifestations. Anti-CASPR2-Ab levels were higher in male patients than in female patients. Moreover, related tumors are relatively rare. Most patients benefit from immunotherapy and have a lower chance of recurrence in the short term. Furthermore, different from patients who had anti-CASPR2-Ab AE alone, those with overlapping syndrome had a severe and complex condition requiring lengthy treatment and rehabilitation. Additional studies are needed to evaluate the long-term prognosis of these patients.

6.
Nat Commun ; 14(1): 1288, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36894541

RESUMO

The accurate radio frequency (RF) ranging and localizing of objects has benefited the researches including autonomous driving, the Internet of Things, and manufacturing. Quantum receivers have been proposed to detect the radio signal with ability that can outperform conventional measurement. As one of the most promising candidates, solid spin shows superior robustness, high spatial resolution and miniaturization. However, challenges arise from the moderate response to a high frequency RF signal. Here, by exploiting the coherent interaction between quantum sensor and RF field, we demonstrate quantum enhanced radio detection and ranging. The RF magnetic sensitivity is improved by three orders to 21 [Formula: see text], based on nanoscale quantum sensing and RF focusing. Further enhancing the response of spins to the target's position through multi-photon excitation, a ranging accuracy of 16 µm is realized with a GHz RF signal. The results pave the way for exploring quantum enhanced radar and communications with solid spins.

7.
Sci Total Environ ; 877: 162915, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36933713

RESUMO

Moso bamboo (Phyllostachys heterocycla cv. Pubescens) is well known for its high capacity to sequester atmospheric carbon, which has a unique role to play in combating global warming. Many Moso bamboo forests are gradually degrading due to rising labor costs and falling prices for bamboo timber. However, the mechanisms of carbon sequestration of Moso bamboo forest ecosystems in response to degradation are unclear. In this study, a space-for-time substitution approach was used to select Moso bamboo forest plots with the same origin and similar stand types, but different years of degradation, and four degradation sequences, continuous management (CK), 2 years of degradation (D-I), 6 years of degradation (D-II) and 10 years of degradation (D-III). A total of 16 survey sample plots were established based on the local management history files. After a 12-month monitoring, the response characteristics of soil greenhouse gases (GHG) emissions, vegetation, and soil organic carbon sequestration in different degradation sequences were evaluated to reveal the differences in the ecosystem carbon sequestration. The results indicated that under D-I, D-II, and D-III, the global warming potential (GWP) of soil GHG emissions decreased by 10.84 %, 17.75 %, and 31.02 %, while soil organic carbon (SOC) sequestration increased by 2.82 %, 18.11 %, and 4.68 %, and vegetation carbon sequestration decreased by 17.30 %, 33.49 %, and 44.76 %, respectively. In conclusion, compared to CK, the ecosystem carbon sequestration was reduced by 13.79 %, 22.42 %, and 30.31 %, respectively. This suggests that degradation reduces soil GHG emissions but weakens the ecosystem carbon sequestration capability. Therefore, in the background of global warming and the strategic goal of carbon neutrality, restorative management of degraded Moso bamboo forests is critically needed to improve the carbon sequestration potential of the ecosystem.


Assuntos
Ecossistema , Gases de Efeito Estufa , Sequestro de Carbono , Gases de Efeito Estufa/metabolismo , Carbono/análise , Solo , Poaceae/metabolismo , China
8.
Pharm Biol ; 61(1): 316-323, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36695132

RESUMO

CONTEXT: Panax ginseng C. A. Meyer (Araliaceae) is a tonic herb used in ancient Asia. OBJECTIVE: This study investigated the antifatigue effect of P. ginseng on chronic fatigue rats. MATERIALS AND METHODS: Sprague-Dawley rats were divided into control, model and EEP (ethanol extraction of P. ginseng roots) (50, 100 and 200 mg/kg) groups (n = 8). The rats were subcutaneously handled with loaded swimming once daily for 26 days, except for the control group. The animals were intragastrically treated with EEP from the 15th day. On day 30, serum, liver and muscles were collected, and the PI3K/Akt/mTOR signalling pathway was evaluated. RESULTS: The swimming times to exhaust of the rats with EEP were significantly longer than that without it. EEP spared the amount of muscle glycogen, hepatic glycogen and blood sugar under the chronic state. In addition, EEP significantly (p < 0.05) decreased serum triglycerides (1.24 ± 0.17, 1.29 ± 0.04 and 1.20 ± 0.21 vs. 1.58 ± 0.13 mmol/L) and total cholesterol (1.64 ± 0.36, 1.70 ± 0.15 and 1.41 ± 0.19 vs. 2.22 ± 0.19 mmol/L) compared to the model group. Regarding the regulation of energy, EEP had a positive impact on promoting ATPase activities and relative protein expression of the PI3K/Akt/mTOR pathway. CONCLUSIONS: Our results suggested that EEP effectively relieved chronic fatigue, providing evidence that P. ginseng could be a potential dietary supplement to accelerate recovery from fatigue.


Assuntos
Síndrome de Fadiga Crônica , Panax , Ratos , Animais , Proteínas Proto-Oncogênicas c-akt , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Fosfatidilinositol 3-Quinases , Ratos Sprague-Dawley , Serina-Treonina Quinases TOR
9.
Molecules ; 27(14)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35889375

RESUMO

Anti-aging is a challenging and necessary research topic. Momordica charantia L. is a common edible medicinal plant that has various pharmacological activities and is often employed in daily health care. However, its anti-aging effect on mice and the underlying mechanism thereof remain unclear. Our current study mainly focused on the effect of Momordica charantia L. on d-galactose-induced subacute aging in mice and explored the underlying mechanism. UHPLC-Q-Exactive Orbitrap MS was applied to qualitatively analyze the chemical components of Momordica charantia L. ethanol extract (MCE). A subacute aging mice model induced by d-galactose (d-gal) was established to investigate the anti-aging effect and potential mechanism of MCE. The learning and memory ability of aging mice was evaluated using behavioral tests. The biochemical parameters, including antioxidant enzyme activity and the accumulation of lipid peroxides in serum, were measured to explore the effect of MCE on the redox imbalance caused by aging. Pathological changes in the hippocampus were observed using hematoxylin and eosin (H&E) staining, and the levels of aging-related proteins in the PI3K/AKT signaling pathway were assessed using Western blotting. The experimental results demonstrated that a total of 14 triterpenoids were simultaneously identified in MCE. The behavioral assessments results showed that MCE can improve the learning and memory ability of subacute mice. The biochemical parameters determination results showed that MCE can improve the activity of antioxidant enzymes and decrease the accumulation of lipid peroxides in aging mice significantly. Furthermore, aging and injury in the hippocampus were ameliorated. Mechanistically, the results showed a significant upregulation in the protein expression of P-PI3K/PI3K and P-AKT/AKT (p < 0.01), as well as a significant reduction in cleaved caspase-3/caspase-3, Bax and P-mTOR/mTOR (p < 0.01). Our results confirm that MCE could restore the antioxidant status and improve cognitive impairment in aging mice, inhibit d-gal-induced apoptosis by regulating the PI3K/AKT signaling pathway, and rescue the impaired autophagy caused by mTOR overexpression, thereby exerting an anti-aging effect.


Assuntos
Momordica charantia , Envelhecimento , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Caspase 3/metabolismo , Galactose/efeitos adversos , Peróxidos Lipídicos , Camundongos , Momordica charantia/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
10.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(4): 372-376, 2022 Apr 15.
Artigo em Chinês | MEDLINE | ID: mdl-35527410

RESUMO

OBJECTIVES: To study the clinical manifestations and gastroscopic characteristics of upper gastrointestinal ulcer in children. METHODS: A retrospective analysis was performed for the children who underwent gastroscopy and were found to have upper gastrointestinal ulcer for the first time at the Endoscopy Center of Shengjing Hospital, China Medical University, from January 2011 to May 2021. According to the cause of the disease, they were divided into primary ulcer group (primary group; n=148) and secondary ulcer group (secondary group; n=25). The clinical data were compared between the two groups. RESULTS: A total of 173 children with upper gastrointestinal ulcer were enrolled, with a male/female ratio of 3.9:1. Compared with girls, boys had significantly higher proportions of duodenal ulcer and primary ulcer (P<0.05). Compared with the children aged below 6 years, the children aged 6-14 years had higher proportions of duodenal ulcer and primary ulcer and lower proportions of giant ulcer and multiple ulcers. Of the 148 children in the primary group, 95 (64.2%) had Helicobacter pylori infection. Abdominal pain was the most common clinical symptom and was observed in 101 children (68.2%). Duodenal ulcer was common and was observed in 115 children (77.7%), followed by gastric ulcer in 25 children (16.9%) and esophageal ulcer in 7 children (4.7%). Multiple ulcers were observed in 32 children (21.6%). Seventy children (47.3%) experienced complications, among which bleeding was the most common complication and was observed in 63 children (43.6%). Of the 25 children in the secondary group, abdominal pain was the most common clinical symptom and was observed in 9 children (36.0%), with a significantly lower incidence rate than the primary group (P<0.05); foreign body in the digestive tract was the most common cause of ulcer and was observed in 17 children (68%), followed by abdominal Henoch-Schönlein purpura in 5 children (20.0%) and Crohn's disease in 3 children (12.0%). The secondary group had a significantly higher proportion of multiple ulcer or giant ulcer than the primary group (P<0.05). CONCLUSIONS: Upper gastrointestinal ulcer is more common in boys than girls, and duodenal ulcer and primary ulcer are more common in boys. Children aged 6-14 years often have duodenal ulcer and primary ulcer, and giant ulcer and multiple ulcers are relatively uncommon. Primary ulcer in children has a variety of clinical manifestations, mainly abdominal pain, and duodenal ulcer is relatively common, with bleeding as the main complication. The clinical symptoms and endoscopic manifestations of secondary ulcer are closely associated with the primary causes, and it is more likely to induce huge ulcers and multiple ulcers.


Assuntos
Úlcera Duodenal , Infecções por Helicobacter , Helicobacter pylori , Dor Abdominal , Criança , Úlcera Duodenal/complicações , Úlcera Duodenal/diagnóstico , Úlcera Duodenal/epidemiologia , Endoscopia Gastrointestinal/efeitos adversos , Feminino , Infecções por Helicobacter/complicações , Infecções por Helicobacter/diagnóstico , Humanos , Masculino , Estudos Retrospectivos , Úlcera
11.
Angew Chem Int Ed Engl ; 61(21): e202116865, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35132759

RESUMO

Chemical modification of electrode materials by heteroatom dopants is crucial for improving storage performance in rechargeable batteries. Electron configurations of different dopants significantly influence the chemical interactions inbetween and the chemical bonding with the host material, yet the underlying mechanism remains unclear. We revealed competitive doping chemistry of Group IIIA elements (boron and aluminum) taking nickel-rich cathode materials as a model. A notable difference between the atomic radii of B and Al accounts for different spatial configurations of the hybridized orbital in bonding with lattice oxygen. Density functional theory calculations reveal, Al is preferentially bonded to oxygen and vice versa, and shows a much lower diffusion barrier than BIII . In the case of Al-preoccupation, the bulk diffusion of BIII is hindered. In this way, a B-rich surface and Al-rich bulk is formed, which helps to synergistically stabilize the structural evolution and surface chemistry of the cathode.

12.
Angew Chem Int Ed Engl ; 60(18): 10211-10218, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33555634

RESUMO

The first iron-catalyzed defluorosilylation of unactivated gem-difluoroalkenes was developed, delivering gem-disilylated alkenes and (E)-silylated alkenes with excellent efficiency. This protocol features good functional group compatibility and excellent regio- and stereoselectivity, enabling the late-stage silylation of biologically relevant compounds, thus providing good opportunities for applications in medicinal chemistry. Preliminary mechanistic studies and DFT calculations reveal that a nucleophilic addition and elimination of the second C-F bond might be involved in the disilylation catalytic system, demonstrating unusual reactivity characteristics of iron catalysis.

13.
Org Lett ; 20(15): 4641-4644, 2018 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-30043613

RESUMO

An efficient Fe(TPP)Cl catalyzed insertion reaction of in situ generated benzylic carbenes from N-tosylhydrazones into X-H (X = Si, Sn, Ge) was developed. Silanes bearing tertiary, secondary, and primary (3°, 2°, and 1°) Si-H bonds all reacted well to afford insertion products in moderate to high yields (up to 97%), and the reaction time could be significantly shortened to 1 h under microwave irradiation. A programmable stepwise double insertion strategy was developed for the synthesis of unsymmetrical tetrasubstituted silanes.

14.
Macromol Biosci ; 14(4): 588-96, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24254404

RESUMO

A Pt (IV) complex which combined the bioactivities of both oxaliplatin and demethylcantharidin (DMC) is synthesized and delivered by a polymer-drug conjugate for combination chemotherapy. Oxaliplatin is released from the polymer-drug conjugate within cancer cell by reduction to attack nuclear DNA, while a dose of DMC is also hydrolyzed subsequently to block DNA damage-induced defense mechanisms by serine/threonine phosphatase 2A (PP2A) inhibition. In vitro evaluation shows that the polymer-drug conjugate with dual modes of action upon cancer cells displays higher cytotoxicity against SKOV-3 cells than that of free drugs. This enhanced cytotoxicity is attributed to the synergistic effect between oxaliplatin and DMC, as well as the effective intracellular internalization of the micelles observed by confocal laser scanning microscopy (CLSM) imaging.


Assuntos
Cantaridina/análogos & derivados , Neoplasias/tratamento farmacológico , Compostos Organoplatínicos/administração & dosagem , Polímeros/administração & dosagem , Cantaridina/administração & dosagem , Cantaridina/química , Linhagem Celular Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral/ultraestrutura , Humanos , Micelas , Microscopia Confocal , Neoplasias/patologia , Compostos Organoplatínicos/química , Oxaliplatina , Polímeros/química
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