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Plants deploy receptor-like kinases and nucleotide-binding leucine-rich repeat receptors to confer host plant resistance (HPR) to herbivores1. These gene-for-gene interactions between insects and their hosts have been proposed for more than 50 years2. However, the molecular and cellular mechanisms that underlie HPR have been elusive, as the identity and sensing mechanisms of insect avirulence effectors have remained unknown. Here we identify an insect salivary protein perceived by a plant immune receptor. The BPH14-interacting salivary protein (BISP) from the brown planthopper (Nilaparvata lugens Stål) is secreted into rice (Oryza sativa) during feeding. In susceptible plants, BISP targets O. satvia RLCK185 (OsRLCK185; hereafter Os is used to denote O. satvia-related proteins or genes) to suppress basal defences. In resistant plants, the nucleotide-binding leucine-rich repeat receptor BPH14 directly binds BISP to activate HPR. Constitutive activation of Bph14-mediated immunity is detrimental to plant growth and productivity. The fine-tuning of Bph14-mediated HPR is achieved through direct binding of BISP and BPH14 to the selective autophagy cargo receptor OsNBR1, which delivers BISP to OsATG8 for degradation. Autophagy therefore controls BISP levels. In Bph14 plants, autophagy restores cellular homeostasis by downregulating HPR when feeding by brown planthoppers ceases. We identify an insect saliva protein sensed by a plant immune receptor and discover a three-way interaction system that offers opportunities for developing high-yield, insect-resistant crops.
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Hemípteros , Proteínas de Insetos , Oryza , Defesa das Plantas contra Herbivoria , Proteínas de Plantas , Animais , Hemípteros/imunologia , Hemípteros/fisiologia , Leucina/metabolismo , Nucleotídeos/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/imunologia , Oryza/metabolismo , Oryza/fisiologia , Defesa das Plantas contra Herbivoria/imunologia , Defesa das Plantas contra Herbivoria/fisiologia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Proteínas de Insetos/metabolismo , AutofagiaRESUMO
Prostate cancer (PCa) is a widespread global health concern characterized by elevated rates of occurrence, and there is a need for novel therapeutic targets to enhance patient outcomes. FOXS1 is closely linked to different cancers, but its function in PCa is still unknown. The expression of FOXS1, its prognostic role, clinical significance in PCa, and the potential mechanism by which FOXS1 affects PCa progression were investigated through bioinformatics analysis utilizing public data. The levels of FOXS1 and HILPDA were evaluated in clinical PCa samples using various methods, such as western blotting, immunohistochemistry, and qRT-PCR. To examine the function and molecular mechanisms of FOXS1 in PCa, a combination of experimental techniques including CCK-8 assay, flow cytometry, wound-healing assay, Transwell assay, and Co-IP assay were employed. The FOXS1 expression levels were significantly raised in PCa, correlating strongly with tumor aggressiveness and an unfavorable prognosis. Regulating FOXS1 expression, whether upregulating or downregulating it, correspondingly enhanced or inhibited the growth, migration, and invasion capabilities of PCa cells. Mechanistically, we detected a direct interaction between FOXS1 and HILPDA, resulting in the pathway activation of FAK/PI3K/AKT and facilitation EMT in PCa cells. FOXS1 collaborates with HILPDA to initiate EMT, thereby facilitating the PCa progression through the FAK/PI3K/AKT pathway activation.
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Transição Epitelial-Mesenquimal , Fatores de Transcrição Forkhead , Regulação Neoplásica da Expressão Gênica , Fosfatidilinositol 3-Quinases , Neoplasias da Próstata , Proteínas Proto-Oncogênicas c-akt , Humanos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Masculino , Fatores de Transcrição Forkhead/metabolismo , Fatores de Transcrição Forkhead/genética , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral , Quinase 1 de Adesão Focal/metabolismo , Quinase 1 de Adesão Focal/genética , Transdução de Sinais , Regulação para Cima , Movimento Celular , Proliferação de Células , Animais , Camundongos , Oncogenes , Prognóstico , Camundongos NusRESUMO
Schistosome infection and schistosome-derived products have been implicated in the prevention and alleviation of inflammatory bowel disease by manipulating the host immune response, whereas the role of gut microbiota in this protective effect remains poorly understood. In this study, we found that the intraperitoneal immunization with Schistosoma japonicum eggs prior to dextran sulfate sodium (DSS) application significantly ameliorated the symptoms of DSS-induced acute colitis, which was characterized by higher body weight, lower disease activity index score and macroscopic inflammatory scores. We demonstrated that the immunomodulatory effects of S. japonicum eggs were accompanied by an influence on gut microbiota composition, abundance, and diversity, which increased the abundance of genus Turicibacter, family Erysipelotrichaceae, phylum Firmicutes, and decreased the abundance of genus Odoribacter, family Marinifilaceae, order Bacteroidales, class Bacteroidia, phylum Bacteroidota. In addition, Lactobacillus was identified as a biomarker that distinguishes healthy control mice from DSS-induced colitis mice. The present study revealed the importance of the gut microbiota in S. japonicum eggs exerting protective effects in an experimental ulcerative colitis (UC) model, providing an alternative strategy for the discovery of UC prevention and treatment drugs.
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Colite Ulcerativa , Sulfato de Dextrana , Modelos Animais de Doenças , Microbioma Gastrointestinal , Schistosoma japonicum , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Colite Ulcerativa/microbiologia , Colite Ulcerativa/imunologia , Camundongos , Schistosoma japonicum/imunologia , Sulfato de Dextrana/toxicidade , Feminino , Imunização/métodos , Óvulo , Camundongos Endogâmicos C57BLRESUMO
Constructing redox semiconductor heterojunction photocatalysts is the most effective and important means to complete the artificial photosynthetic overall reaction (i.e., coupling CO2 photoreduction and water photo-oxidation reactions). However, multiphase hybridization essence and inhomogeneous junction distribution in these catalysts extremely limit the diverse design and regulation of the modes of photogenerated charge separation and transfer pathways, which are crucial factors to improve photocatalytic performance. Here, we develop molecular oxidation-reduction (OR) junctions assembled with oxidative cluster (PMo12, for water oxidation) and reductive cluster (Ni5, for CO2 reduction) in a direct (d-OR), alternant (a-OR), or symmetric (s-OR) manner, respectively, for artificial photosynthesis. Significantly, the transfer direction and path of photogenerated charges between traditional junctions are obviously reformed and enriched in these well-defined crystalline catalysts with monophase periodic distribution and thus improve the separation efficiency of the electrons and holes. In particular, the charge migration in s-OR shows a periodically and continuously opposite mode. It can inhibit the photogenerated charge recombination more effectively and enhance the photocatalytic performance largely when compared with the traditional heterojunction models. Structural analysis and density functional theory calculations disclose that, through adjusting the spatial arrangement of oxidation and reduction clusters, the energy level and population of the orbitals of these OR junctions can be regulated synchronously to further optimize photocatalytic performance. The establishment of molecular OR junctions is a pioneering important discovery for extremely improving the utilization efficiency of photogenerated charges in the artificial photosynthesis overall reaction.
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Dióxido de Carbono , Luz , Fotossíntese , Oxirredução , Água/químicaRESUMO
The battery performance declines significantly in severely cold areas, especially discharge capacity and cycle life, which is the most significant pain point for new energy consumers. To address this issue and improve the low-temperature characteristic of aluminum-ion batteries, in this work, polydopamine-derived N-doped carbon nanospheres are utilized to modify the most promising graphite material. More active sites are introduced into graphite, more ion transport channels are provided, and improved ionic conductivity is achieved in a low-temperature environment. Due to the synergistic effect of the three factors, the ion diffusion resistance is significantly reduced and the diffusion coefficient of aluminum complex ions in the active material become larger at low temperatures. Therefore, the battery delivers an improved capacity retention rate from 23% to 60% at -20 °C and excellent ultra-long cycling stability over 5500 cycles at -10 °C. This provides a novel strategy for constructing low-temperature aluminum-ion batteries with high energy density, which is conducive to promoting the practicality of aluminum-ion batteries.
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Various semiconductor devices have been developed based on 2D heterojunction materials owing to their distinctive optoelectronic properties. However, to achieve efficient charge transfer at their interface remains a major challenge. Herein, an alloy heterojunction concept is proposed. The sulfur vacancies in ZnIn2S4 are filled with selenium atoms of PdSe2. This chemically bonded heterojunction can significantly enhance the separation of photocarriers, providing notable advantages in the field of photoelectric conversion. As a demonstration, a two-terminal photodetector based on the PdSe2/ZnIn2S4 heterojunction materials is fabricated. The photodetector exhibits stable operation in ambient conditions, showcasing superior performance in terms of large photocurrent, high responsivity (48.8 mA W-1) and detectivity (1.98 × 1011 Jones). To further validate the excellent optoelectronic performance of the heterojunction, a tri-terminal phototransistor is also fabricated. Benefiting from gate voltage modulation, the photocurrent is amplified to milliampere level, and the responsivity is increased to 229.14 mA W-1. These findings collectively demonstrate the significant potential of the chemically bonded PdSe2/ZnIn2S4 alloy heterojunction for future optoelectronic applications.
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BACKGROUND: Depression is a neuropsychiatric disease with a high disability rate and mainly caused by the chronic stress or genetic factors. There is increasing evidence that microRNAs (miRNAs) play a critical role in the pathogenesis of depression. However, the underlying molecular mechanism for the pathophysiology of depression of miRNA remains entirely unclear so far. METHODS: We first established a chronic social defeat stress (CSDS) mice model of depression, and depression-like behaviors of mice were evaluated by a series of behavioral tests. Next, we detected several abundantly expressive miRNAs suggested in previous reports to be involved in depression and found miR-182-5p was selected as a candidate for analysis in the hippocampus. Then western blotting and immunofluorescence were used together to examine whether adeno-associated virus (AAV)-siR-182-5p treatment alleviated chronic stress-induced decrease in hippocampal Akt/GSK3ß/cAMP-response element binding protein (CREB) signaling pathway and increase in neurogenesis impairment and neuroinflammation. Furthermore, CREB inhibitor was adopted to examine if blockade of Akt/GSK3ß/CREB signaling pathway abolished the antidepressant actions of AAV-siR-182-5p in mice. RESULTS: Knockdown of miR-182-5p alleviated depression-like behaviors and impaired neurogenesis of CSDS-induced mice. Intriguingly, the usage of agomiR-182-5p produced significant increases in immobility times and aggravated neuronal neurogenesis damage of mice. More importantly, it suggested that 666-15 blocked the reversal effects of AAV-siR-182-5p on the CSDS-induced depressive-like behaviors in behavioral testing and neuronal neurogenesis within hippocampus of mice. CONCLUSIONS: These findings indicated that hippocampal miR-182-5p/Akt/GSK3ß/CREB signaling pathway participated in the pathogenesis of depression, and it might give more opportunities for new drug developments based on the miRNA target in the clinic.
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Comportamento Animal , MicroRNAs , Animais , Camundongos , Derrota Social , Glicogênio Sintase Quinase 3 beta/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Hipocampo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Estresse Psicológico/metabolismoRESUMO
Economic development and increased stress have considerably increased the prevalence of psychiatric disorders in recent years, which rank as some of the most prevalent diseases globally. Several factors, including chronic social stress, genetic inheritance, and autogenous diseases, lead to the development and progression of psychiatric disorders. Clinical treatments for psychiatric disorders include psychotherapy, chemotherapy, and electric shock therapy. Although various achievements have been made researching psychiatric disorders, the pathogenesis of these diseases has not been fully understood yet, and serious adverse effects and resistance to antipsychotics are major obstacles to treating patients with psychiatric disorders. Recent studies have shown that the mammalian target of rapamycin (mTOR) is a central signaling hub that functions in nerve growth, synapse formation, and plasticity. The PI3K-AKT/mTOR pathway is a critical target for mediating the rapid antidepressant effects of these pharmacological agents in clinical and preclinical research. Abnormal PI3K-AKT/mTOR signaling is closely associated with the pathogenesis of several neurodevelopmental disorders. In this review, we focused on the role of mTOR signaling and the related aberrant neurogenesis in psychiatric disorders. Elucidating the neurobiology of the PI3K-AKT/mTOR signaling pathway in psychiatric disorders and its actions in response to antidepressants will help us better understand brain development and quickly identify new therapeutic targets for the treatment of these mental illnesses.
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Transtornos Mentais , Proteínas Proto-Oncogênicas c-akt , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Sirolimo/farmacologia , Antidepressivos/farmacologia , Transtornos Mentais/tratamento farmacológicoRESUMO
BACKGROUND: Microbial infection and colonization are frequently associated with disease progression and poor clinical outcomes in bronchiectasis. Identification of pathogen spectrum is crucial for precision treatment at exacerbation of bronchiectasis. METHODS: We conducted a prospective cohort study in patients with bronchiectasis exacerbation onset and stable state. Bronchoalveolar lavage fluid (BALF) was collected for conventional microbiological tests (CMTs) and metagenomic Next-Generation Sequencing (mNGS). Bronchiectasis patients were monitored for documenting the time to the next exacerbation during longitudinal follow-up. RESULTS: We recruited 168 eligible participants in the exacerbation cohorts, and 38 bronchiectasis patients at stable state at longitudinal follow-up. 141 bronchiectasis patients at exacerbation onset had definite or probable pathogens via combining CMTs with mNGS reports. We identified that Pseudomonas aeruginosa, non-tuberculous mycobacteria, Haemophilus influenzae, Nocardia spp, and Staphylococcus aureus were the top 5 pathogens with a higher detection rate in our cohorts via combination of CMTs and mNGS analysis. We also observed strong correlations of Pseudomonas aeruginosa, Haemophilus influenzae, non-tuberculous mycobacteria with disease severity, including the disease duration, Bronchiectasis Severity Index, and lung function. Moreover, the adjusted pathogenic index of potential pathogenic microorganism negatively correlated (r = -0.7280, p < 0.001) with the time to the next exacerbation in bronchiectasis. CONCLUSION: We have revealed the pathogenic microbial spectrum in lower airways and the negative correlation of PPM colonization with the time to the next exacerbation in bronchiectasis. These results suggested that pathogens contribute to the progression of bronchiectasis.
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Bronquiectasia , Humanos , Bronquiectasia/microbiologia , Bronquiectasia/diagnóstico , Feminino , Masculino , Estudos Prospectivos , Pessoa de Meia-Idade , Idoso , Líquido da Lavagem Broncoalveolar/microbiologia , Estudos de Coortes , Seguimentos , Adulto , Progressão da Doença , Estudos LongitudinaisRESUMO
Trichinellosis caused by Trichinella spiralis (T. spiralis) is a major food-borne parasitic zoonosis worldwide. Prevention of trichinellosis is an effective strategy to improve patient quality of life. Macrophage migration inhibitory factor (MIF) is closely related to the occurrence and development of several parasitic diseases. Studying the impact of MIF deficiency (Mif-/- ) on the alterations in host fecal microbiota due to T. spiralis infection may contribute to proposing a novel dual therapeutic approach for trichinellosis. To reveal the diversity and differences in fecal microbial composition, feces were collected from T. spiralis-uninfected and T. spiralis-infected wild-type (WT) and MIF knockout (KO) C57BL/6 mice at 0, 7, 14, and 35 days post-infection (dpi), and the samples were sent for 16S rRNA amplicon sequencing on the Illumina NovaSeq platform. Flow cytometry was used to determine the expression levels of IFN-γ and IL-4 in the CD4+ /CD8+ T-cell sets of mouse spleens. The results showed that operational taxonomic unit (OTU) clustering, relative abundance of microbial composition, alpha diversity, and beta diversity exhibited significant changes among the eight groups. The LEfSe analysis selected several potential biomarkers at the genus or species level, including Akkermansia muciniphila, Lactobacillus murinus, Coprococcus catus, Firmicutes bacterium M10_2, Parabacteroides sp. CT06, and Bacteroides between the KTs and WTs groups. The predicted bacterial functions of the fecal microbiota were mainly involved in metabolism, such as the metabolism of carbohydrates, amino acids, energy, cofactors, vitamins, nucleotides, glycans, and lipids. Flow cytometry revealed an increased CD3+ CD8- /CD3+ CD8+ T-cell ratio and increased IFN-γ and IL-4 levels in CD3+ CD8- T-cell sets from WT and MIF KO mice at 7 dpi. The results indicated that both MIF KO and infection time have a significant influence on the CD3+ CD8- IFN-γ+ and CD3+ CD8- IL-4+ response in mice after T. spiralis. In conclusion, this research showed alterations of the fecal microbiota and immune response in both WT and MIF KO mice before and after T. spiralis infection. These results revealed a potential role of MIF in regulating the pathogenesis of trichinellosis related to the intestinal microbiota. Importantly, the selected potential biomarkers combined with MIF will also offer a novel therapeutic approach to treat trichinellosis in the future.
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Fatores Inibidores da Migração de Macrófagos , Microbiota , Trichinella spiralis , Triquinelose , Animais , Humanos , Camundongos , Interleucina-4 , Oxirredutases Intramoleculares , Fatores Inibidores da Migração de Macrófagos/genética , Camundongos Endogâmicos C57BL , Qualidade de Vida , RNA Ribossômico 16S/genéticaRESUMO
The host effect of the supramolecular [Ga4L6]12- tetrahedral metallocage on Prins cyclization reaction of the substrate by encapsulated citronellal has been investigated by means of molecular dynamics and quantum mechanics. The encapsulation process of the substrate into the [Ga4L6]12- cavity was simulated via attach-pull-release (APR) methods. Thermodynamic calculations and classical molecular dynamics simulations assessed the substrate's microenvironment inside the cavity, guiding DFT-level modeling of the reaction. DFT calculations show diol product predominance in acidic solution but high enol selectivity inside [Ga4L6]12-, consistent with experimental findings. [Ga4L6]12- alters the selectivity of the Prins cyclization reaction by inhibiting diol formation. The activation strain model-based decomposition analysis (ASM-DA) of the barrier difference among distortion and interaction terms indicates that the more positive interaction between a host and guest in the diol transition state than enol determines the product selectivity, particularly the fewer C-H···O and O-H···O hydrogen-bonding interactions. These theoretical insights could contribute to a deeper understanding of the nature of supramolecular catalysis and to further develop new supramolecular catalysts.
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BACKGROUND: Renal sinus angiomyolipoma (RSAML) is a rare and typically complex renal tumor. The objective is to present our single-center experience with a modified technique of robotic nephron-sparing surgery (NSS) for treating RSAML. METHODS: We retrospectively evaluated 15 patients with RSAMLs who were treated with robotic NSS at the Department of Urology of Tongji hospital, ranging from November 2018 to September 2022. Renal vessels and ureter were dissected. The outer part of RSAML was resected. The rest of tumor was removed by bluntly grasp, curettage and suction. Absorbable gelatin sponges were filled in the renal sinus. The preoperative parameters, operative measures and postoperative outcomes were all collected. Follow-up was performed by ultrasonography and estimated glomerular filtration rate (eGFR). RESULTS: Robotic NSS was successfully performed in all the patients, without any conversion to open surgery or nephrectomy. The mean operation time was 134.13 ± 40.56 min. The mean warm ischemia time was 25.73 ± 3.28 min. The median estimated blood loss was 100 [50, 270] ml and 1 patient required blood transfusion. The mean drainage duration was 5.77 ± 1.98 days. The median postoperative hospital stay was 6.90 [5.80, 8.70] days. Two patients experienced postoperative urinary tract infection (Clavien-Dindo Grade II). During the median follow-up of 25.53 ± 15.28 months, patients received 91.18% renal function preservation. No local recurrence occurred in all the patients. CONCLUSIONS: Robotic NSS for RSAML is a complicated procedure that demands technical expertise and a well-designed strategy is critical in the operation. Treating RSAML with modified robotic NSS is safe, effective and feasible.
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Angiomiolipoma , Neoplasias Renais , Néfrons , Tratamentos com Preservação do Órgão , Procedimentos Cirúrgicos Robóticos , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Neoplasias Renais/cirurgia , Feminino , Estudos Retrospectivos , Adulto , Masculino , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão/métodos , Angiomiolipoma/cirurgia , Néfrons/cirurgia , Nefrectomia/métodosRESUMO
Natural products are closely associated with human health. Luteolin (LUT), a flavonoid polyphenolic compound, is widely found in fruits, vegetables, flowers, and herbs. It is noteworthy that LUT exhibits a variety of beneficial pharmacological properties and holds significant potential for clinical applications, particularly in antitumor, anti-convulsion, diabetes control, anti-inflammatory, neuroprotection, anti-oxidation, anti-cardiovascular, and other aspects. The potential mechanism of action has been partially elucidated, including the mediation of NF-κB, toll-like receptor, MAPK, Wnt/ß-catenin, PI3K/Akt, AMPK/mTOR, and Nrf-2, among others. The review that aimed to comprehensively consolidate essential information on natural sources, pharmacological effects, therapeutic and preventive potential, as well as potential mechanisms of LUT. The objective is to establish a theoretical basis for the continued development and application of LUT.
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Luteolina , Humanos , Luteolina/farmacologia , Flavonoides/farmacologia , Flavonoides/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Animais , Antioxidantes/farmacologiaRESUMO
Six novel withanolides, along with nine known related compounds were isolated from the leaves of Datura stramonium L. The structures and absolute configurations of the new withanolides were elucidated by employing various spectral techniques and comparing them with those previously reported in the literature. In addition, four withanlides demonstrated interesting cytotoxic activity on LN229 cells with IC50 <20â µM.
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Antineoplásicos , Datura stramonium , Vitanolídeos , Vitanolídeos/farmacologia , Vitanolídeos/química , Estrutura Molecular , Folhas de Planta/químicaRESUMO
The streaming potential effect has a wide range of applications in geophysics. The core streaming potential experiment requires that there is no external circuit at both ends of the core, but a measurement circuit must be introduced to measure the voltage between both ends of the core which will cause an external circuit. In order to analyze the effect of measurement circuits on the streaming potential experiment, this paper proposes a core current source model, i.e., the core in the streaming potential experiment is regarded as a circuit composed of a current source whose output current is equal to the seepage current and the core resistance. By changing the resistance value of the external circuit, it is found that the seepage current is not affected by the external resistance but by the excitation pressure. Experiments on the streaming potential of 20 sandstone cores under distilled water, 0.01 mol/L, 0.02 mol/L, 0.05 mol/L, 0.1 mol/L, 0.2 mol/L, 0.4 mol/L, and 0.6 mol/L sodium chloride solutions revealed that the effect of the external circuit on the streaming potential signal increased with decreasing mineralization. For distilled water-saturated sandstone cores, the effect of the external circuit was about 2%.
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Electroosmotic experiments obtain the electroosmotic pressure coefficient of a rock sample by measuring the excitation voltage at both ends of the sample and the pressure difference caused by the excitation voltage. The electroosmotic pressure is very weak and buried in the background noise, which is the most difficult signal to measure in the dynamic-electric coupling experiment, so it is necessary to improve its signal-to-noise ratio. In this paper, for the low signal-to-noise ratio of electroosmotic pressure, the dual pressure sensor method is proposed, i.e., two pressure sensors of the same type are used to measure electroosmotic pressure. Two different data extraction methods, Fast Fourier Transform and Locked Amplification, are utilized to compare the dual pressure sensor method of this paper with the existing single pressure sensor method. The relationship between the electroosmotic pressure coefficient and the excitation frequency, mineralization, permeability, and porosity is analyzed and discussed.
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Motion cables, which are widely used in aero-engine sensors, are critical components that determine sensor stability. Because motion cables have unique motion characteristics, the study of their mechanical properties and reliability is very important. In addition, motion cables are complex in structure and cannot be applied to conventional fixed cable research methods. In this study, a new approach is proposed to introduce the theory of anisotropic composites into a simplified cable model, so that the cable is both physically conditioned and has good mechanical properties. While applying the theory of anisotropic composites, the forces of tension and torsion are considered in a motion cable under the combined action. In this context, the reliability of the structure is the fatigue life of the cable. In this paper, the mechanical properties and fatigue life of motion cables are investigated using the finite element method at different inclination angles and fixation points. The simulation results show that there is a positive correlation between the inclination angle and the extreme stress in the motion cables, and the optimal inclination angle of 0° is determined. The number of fixing points should be reduced to minimize the additional moments generated during the movement and to ensure proper movement of the cables. The optimal configuration is a 0° inclination angle and two fixing points. Subsequently, the fatigue life under these optimal conditions is analyzed. The results show that the high-stress zone corresponds to the location of the short-fatigue life, which is the middle of the motion cables. Therefore, minimizing the inclination angle and the number of fixing points of the motion cables may increase their fatigue life and thus provide recommendations for optimizing their reliability.
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BACKGROUND: China has been using inactivated coronavirus disease 2019 (COVID-19) vaccines as primary series and booster doses to protect the population from severe to fatal COVID-19. We evaluated primary and booster vaccine effectiveness (VE) against Omicron BA.2 infection outcomes. METHODS: This was a 13-province retrospective cohort study of quarantined close contacts of BA.2-infected individuals. Outcomes were BA.2 infection, COVID-19 pneumonia or worse, and severe/critical COVID-19. Absolute VE was estimated by comparison with an unvaccinated group. RESULTS: There were 289 427 close contacts ≥3 years old exposed to Omicron BA.2 cases; 31 831 turned nucleic acid amplification test-positive during quarantine, 97.2% with mild or asymptomatic infection, 2.6% with COVID-19 pneumonia, and 0.15% with severe/critical COVID-19. None died. Adjusted VE (aVE) against any infection was 17% for primary series and 22% when boosted. Primary series aVE in adults >18 years was 66% against COVID-19 pneumonia or worse and 91% against severe/critical COVID-19. Booster dose aVE was 74% against pneumonia or worse, and 93% against severe/critical COVID-19. CONCLUSIONS: Inactivated COVID-19 vaccines provided modest protection from infection, very good protection against pneumonia, and excellent protection against severe/critical COVID-19. Booster doses are necessary to provide strongest protection.
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Vacinas contra COVID-19 , COVID-19 , Adulto , Humanos , Pré-Escolar , COVID-19/prevenção & controle , Estudos Retrospectivos , China/epidemiologia , Infecções AssintomáticasRESUMO
The two-dimensional (2D) MXenes with sufficient interlayer spacing are promising cathode materials for aluminum-ion batteries (AIBs), yet the electrostatic repulsion effect between the surface negative charges and the active anions (AlCl4 - ) hinders the intercalation of AlCl4 - and is usually ignored. Here, we propose a charge regulation strategy for MXene cathodes to overcome this challenge. By doping N and Co, the zeta potential is gradually transformed from negative (Ti3 C2 Tx ) to near-neutral (Ti3 CNTx ), and finally positive (Ti3 CNTx @Co). Therefore, the electrostatic repulsion force can be greatly weakened between Ti3 CNTx and AlCl4 - , or even formed a strong electrostatic attraction between Ti3 CNTx @Co and AlCl4 - , which can not only accommodate more AlCl4 - ions in the Ti3 CNTx @Co interlayers to increase the capacity, but also solve the stacking and expansion problems. As a result, the optimized Al-MXene battery exhibits an ultrahigh capacity of up to 240â mAh g-1 (2-4â times the capacity of graphite cathode, 60-120â mAh g-1 ) and a potential ultrahigh energy density (432â Wh kg-1 , 2-4â times the value of graphite, 110-220â Wh kg-1 ) based on the mass of cathode materials, comparable to LiFePO4 -based lithium-ion batteries (350-450â Wh kg-1 , based on the mass of LiFePO4 ).
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Non-radiative recombination, caused by trap states, significantly hampers the efficiency and stability of perovskite solar cells (PSCs). The emerging porous organic polymers (POPs) show promise as a platform for designing novel defect passivation agents due to their rigid and porous structure. However, the POPs reported so far lack either sufficient stability or clear sites of interactions with the defects. Herein, two chlorine-functionalized, fully conjugated porous aromatic frameworks (PAFs) were constructed via a decarbonylation reaction. The chlorinated PAFs feature unique long-range conjugated networks bearing multiple chlorine atoms, significantly improving the photovoltaic performance and stability of doped solar cells. Combined experimental and theoretical analyses confirmed the strong passivation effects of conjugated structure to the defect through Cl sites. Specifically, PAF-159, bearing a triphenylamine moiety, demonstrated stronger Cl-Pb bonding and higher passivation efficiency due to the presence of π* anti-bonding orbitals, which elevate the HOMO energy level and facilitate Cl-Pb charge transfer. Consequently, we obtained high-performance PAF-159-doped devices with advanced PCE (24.3%), good storage stability (retaining 86% after 3000 hours), and good long-term operational stability (retaining 92% after 350 hours).