RESUMEN
Wood, as a natural biomass material, has long been a research focus. Superhydrophobic modified wood, in particular, has shown great promise in a myriad of engineering applications such as architecture, landscape, and shipbuilding. However, commercial development has encountered significant resistance due to preparation difficulties and sometimes unsatisfactory performance. In this study, hydrophobic/superhydrophobic wood comodified with methyltrimethoxysilane (MTMS) and 1H,1H,2H,2H-perfluorodecyltrimethoxysilane (PFDTMS) was fabricated by a one-step sol-gel method that uses an in situ growth process. Low-molecular-weight MTMS was allowed to permeate the three-dimensional porous wood interior. Then, acid-base catalysts were used to regulate the hydrolytic condensation process of MTMS and PFDTMS composite silanes to generate micro/nano hierarchical structures with low surface energy on the wood surface. The physicochemical characteristics of modified wood were investigated and the reaction mechanism established. The modified wood displayed excellent internal hydrophobicity/surface superhydrophobicity, water-moisture resistance, and dimensional stability at low fluorine concentrations. The resulting superhydrophobic surface provided stain resistance, self-cleaning ability, and loading capacity in water while exhibiting good mechanochemical stability; wood mechanical strength was also enhanced. This methodology created a superhydrophobic surface and bulk hydrophobization of wood in one step. Beyond wood, this approach is expected to provide a promising approach for functional modification of other porous composite materials.
RESUMEN
Enhancing catalytic activity while inhibiting the generation of chlorine byproducts is essential in the catalytic oxidation process of chlorinated volatile organic compounds (CVOCs). In this study, Cr-modified Co/WNb catalysts were synthesized and utilized for the degradation of dichloromethane (DCM). It was found that the moderate introduction of Cr exposed more Cr6+ on the catalyst surface due to the interaction between cobalt and chromium oxides, which promoted the generation of more chemisorbed oxygen on the surface, thus improving the redox properties and enhancing the activity of the catalysts. Additionally, the introduction of Cr increased the B acid sites of the catalysts, promoting the breaking of C-Cl bonds and the removal of dissociated Cl- Meanwhile, the improved redox properties also allowed further oxidation of the dissociated activated intermediate products and inhibited the generation of chlorine byproducts. The catalyst activity was optimal when the Cr to Co molar ratio was 4, which the T90 of DCM was 256 °C and the monochloromethane selectivity was only 1.7 %. Moreover, Co4Cr/WNb showed excellent chlorine and water resistance, making it an ideal candidate for CVOC degradation.
RESUMEN
The catalytic hydrogenation of carbon dioxide to formate is of great interest due to its significant role in CO2 utilization. In this study, a novel heterogeneous Ru(III) catalyst was prepared by immobilizing RuCl3 on a porous organic polymer (POP) obtained from 1,4-phthalaldehyde (PTA) and 4,4'-biphenyldicarboxaldehyde (BPDA) with melamine. A copolymerization strategy utilizing monomers of varying lengths was employed to prepare the POP-supported Ru catalyst with adjustable porosity. The optimization of the framework porosity resulted in enhanced CO2 affinity, accelerated mass transfer, and a remarkable enhancement in catalytic activity. A high turnover number (TON) of 2458 was achieved for the CO2 hydrogenation to formate in 2 h with catalyst Cat-3 under 3 MPa (CO2/H2 = 1 : 1) at 120 °C in 1 M Et3N aqueous solution. Moreover, the Cat-3 demonstrated good recyclability and was able to be reused for five consecutive runs, resulting in a high total TON of 9971.
RESUMEN
Hinokiflavone (HF), classified as a flavonoid, is a main bioactive compound in Platycladus orientalis and Selaginella. HF exhibits activities including anti-HIV, anti-inflammatory, antiviral, antioxidant and anti-tumor effects. The study aimed to explore the function and the mechanisms of HF on acetaminophen (APAP)-induced acute liver injury. Results indicated that HF treatment mitigated the impact of APAP on viability and restored levels of MDA, GSH and SOD on HepG2 cells. The accumulation of reactive oxygen species (ROS) mitochondrial membrane potential (MMP) in HepG2 cells stimulated by APAP were also blocked by HF. HF reduced the levels of pro-apoptotic and pro-pyroptotic proteins. Flow cytometry analysis and fluorescence staining results were consistent with western blot analysis. Following HF treatment in the APAP-induced cell model, there was observed an augmentation in the phosphorylation of Stat3 and an increase in the expression of SIX4. However, not only silenced the SIX4 protein in HepG2 cells by siRNA, but also adding the Stat3 inhibitor (Stattic), attenuated the anti-apoptotic and anti-pyroptotic effects of HF significantly. Furthermore, HF alleviated liver damage in C57BL/6 mice model. Overall, our study demonstrated that HF mitigates apoptosis and pyroptosis induced by APAP in drug-induced liver injury (DILI) through the SIX4/Akt/Stat3 pathway in vivo and in vitro. HF may have promising potential for for the treatment of DILI.
Asunto(s)
Acetaminofén , Apoptosis , Enfermedad Hepática Inducida por Sustancias y Drogas , Ratones Endogámicos C57BL , Proteínas Proto-Oncogénicas c-akt , Piroptosis , Factor de Transcripción STAT3 , Transducción de Señal , Humanos , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Factor de Transcripción STAT3/metabolismo , Ratones , Apoptosis/efectos de los fármacos , Células Hep G2 , Acetaminofén/toxicidad , Proteínas Proto-Oncogénicas c-akt/metabolismo , Masculino , Piroptosis/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Flavonas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , BiflavonoidesRESUMEN
BACKGROUND: Hair loss profoundly affects women's physical appearance and psychological health. Platelet-rich plasma (PRP) therapy has gained attention as a potential treatment for female hair loss. This systematic review and meta-analysis aim to evaluate the efficacy and safety of PRP in treating different forms of female hair loss. METHODS: A comprehensive search was conducted across PubMed, EMBASE, Scopus, Cochrane Library, Web of Science, and ClinicalTrials.gov from January 2000 to May 2024. The focus was on randomized controlled trials investigating PRP treatment for various types of hair loss in women. The research protocol is registered with International Prospective Register of Systematic Reviews (CRD42024556190). The quality of the studies was evaluated using the Cochrane risk of bias tool (RoB 2). RESULTS: A total of 21 studies comprising 628 participants were included in the analysis. PRP treatment was found to significantly enhance hair density and thickness. Additionally, there was a significant reduction in the number of hairs pulled in the PRP group. Adverse effects were generally mild and transient, with no notable difference in pain or discomfort between the PRP and control groups (risk ratio: 1.01; 95% CI: 0.87-1.18). CONCLUSION: PRP therapy effectively enhances hair density and thickness in women with hair loss, with a favorable safety profile. However, the effects of PRP on hair density and thickness vary with dosage, injection duration, and ethnicity, indicating the need for tailored treatment protocols.
Asunto(s)
Alopecia , Plasma Rico en Plaquetas , Femenino , Humanos , Alopecia/terapia , Cabello , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del TratamientoRESUMEN
ABSTRACT: This study aimed to explore the feasibility of using the ultrasound quantitative scoring system to guide the selection of surgical methods for a cesarean scar ectopic pregnancy (CSEP). A retrospective analysis was conducted of the medical records of 117 cases of patients with a CSEP. All patients underwent transvaginal ultrasound examination before treatment, and the ultrasound results were compared with the results of surgical exploration. The treatment methods that were delivered for the 2 patient groups with CSEP were analyzed, and agreement between the predicted and actual treatment protocols was tested using the kappa consistency test. Residual myometrial thickness at the scar site was mainly concentrated above 3 mm in the low-risk group, with 70 cases accounting for 76.9%, while in the high-risk group, this was primarily in the range of 1-3 mm with 18 cases accounting for 69.2%. The grading of nourishing blood supply to the gestational sac showed that 96.7% of patients in the low-risk group had Grade I and Grade II blood flow, while 84.6% of the high-risk group had Grade I and Grade II blood flow; Grade II blood flow was predominant in the high-risk group. The majority of patients in both the low- and high-risk groups experienced intraoperative blood loss of ≤50 mL (93.9% vs 80.6%, respectively). The consistency test between the actual and predicted treatment methods yielded a kappa coefficient of 0.644, indicating consistency between the two. For patients with CSEP in the low-risk group (score <4), the ultrasound quantitative scoring system could provide individualized assessment and offer clinically valuable treatment protocols.
Asunto(s)
Cesárea , Cicatriz , Valor Predictivo de las Pruebas , Embarazo Ectópico , Humanos , Femenino , Embarazo , Cicatriz/diagnóstico por imagen , Embarazo Ectópico/diagnóstico por imagen , Embarazo Ectópico/cirugía , Estudios Retrospectivos , Adulto , Ultrasonografía Prenatal/métodos , Ultrasonografía/métodos , Estudios de FactibilidadRESUMEN
Pulmonary fibrosis (PF) is a chronic, progressive and irreversible interstitial lung disease characterized by unremitting pulmonary myofibroblasts activation, extracellular matrix (ECM) deposition and inflammatory recruitment. PF has no curable medication yet. In this study we investigated the molecular pathogenesis and potential therapeutic targets of PF and discovered drug lead compounds for PF therapy. A murine PF model was established in mice by intratracheal instillation of bleomycin (BLM, 5 mg/kg). We showed that the protein level of pulmonary protein phosphatase magnesium-dependent 1A (PPM1A, also known as PP2Cα) was significantly downregulated in PF patients and BLM-induced PF mice. We demonstrated that TRIM47 promoted ubiquitination and decreased PPM1A protein in PF progression. By screening the lab in-house compound library, we discovered otilonium bromide (OB, clinically used for treating irritable bowel syndrome) as a PPM1A enzymatic activator with an EC50 value of 4.23 µM. Treatment with OB (2.5, 5 mg·kg-1·d-1, i.p., for 20 days) significantly ameliorated PF-like pathology in mice. We constructed PF mice with PPM1A-specific knockdown in the lung tissues, and determined that by targeting PPM1A, OB treatment suppressed ECM deposition through TGF-ß/SMAD3 pathway in fibroblasts, repressed inflammatory responses through NF-κB/NLRP3 pathway in alveolar epithelial cells, and blunted the crosstalk between inflammation in alveolar epithelial cells and ECM deposition in fibroblasts. Together, our results demonstrate that pulmonary PPM1A activation is a promising therapeutic strategy for PF and highlighted the potential of OB in the treatment of the disease.
RESUMEN
The direct hydrogenation of greenhouse gas CO2 to higher alcohols (C2+OH) provides a new route for the production of high-value chemicals. Due to the difficulty of C-C coupling, the formation of higher alcohols is more difficult compared to that of other compounds. In this review, we summarize recent advances in the development of multifunctional catalysts, including noble metal catalysts, Co-based catalysts, Cu-based catalysts, Fe-based catalysts, and tandem catalysts for the direct hydrogenation of CO2 to higher alcohols. Possible reaction mechanisms are discussed based on the structure-activity relationship of the catalysts. The reaction-coupling strategy holds great potential to regulate the reaction network. The effects of the reaction conditions on CO2 hydrogenation are also analyzed. Finally, we discuss the challenges and potential opportunities for the further development of direct CO2 hydrogenation to higher alcohols.
RESUMEN
The traditional classification of drought events into seasonal and flash types oversimplified the complexity and variability of global drought phenomena, limiting a deeper understanding of drought characteristics and their impacts on vegetation. To address this issue, soil moisture percentile methods and the Soil Moisture Anomaly Percentage Index (SMAPI) were employed to create time series for flash drought (FD) and seasonal drought (SD) events globally from 1981 to 2020. A novel categorization framework was proposed to subdivide the two basic drought categories into eight distinct drought types using a set relationship identification method. The results showed fluctuating trends in the frequencies of Independent FD and Inclusion FD, which declined rapidly after 2011 at rates of 0.05 and 0.04 times/year, respectively. Independent FD frequency was highest in humid areas and decreased with increasing aridity. The spatial distributions of Inclusion FD and SD were similar, with both frequencies highest in extremely arid areas and decreasing with increasing humidity. The frequency of Independent SD, which peaked in semi-arid areas, increased significantly after 2011 at a rate of 0.01 times/year. The occurrence of FD evolving into SD or emerging at the end of SD was rare, with a global average of 0.46 events/decade and little spatial variation. Between 1981 and 2020, FD showed a U-shaped trend in drought duration, while SD showed no clear pattern. The duration of FD showed little difference across arid and humid zones, but the duration of SD decreased significantly with increasing humidity. Vegetation responses to drought varied, with arid regions showing longer response time compared to humid regions. A positive correlation between temperature and solar-induced chlorophyll fluorescence (SIF) during droughts was observed, while precipitation generally showed a negative correlation with SIF. Radiation had a minimal effect on SIF during droughts. The study offered a comprehensive categorization of drought events, enhancing our understanding of their spatiotemporal characteristics and vegetation responses on a global scale.
Asunto(s)
Sequías , Estaciones del Año , Suelo , PlantasRESUMEN
BACKGROUND: With the aging population, the number of individuals with dementia in China is increasing rapidly. This community-based study aimed to investigate the prevalence and risk factors for dementia and mild cognitive impairment (MCI) among older adults in China. METHODS: In this study, 20,070 individuals aged ≥ 65 were recruited between January 1, 2022, and February 1, 2023, from ten communities in Xiamen City, China. We collected data on age, sex, level of education, and medical history, as well as global cognition and functional status. The prevalence of dementia and MCI was examined, and the risk factors for different groups were assessed. RESULTS: The overall prevalence of dementia and MCI was approximately 5.4% (95% confidence interval [CI], 5.1-5.7) and 7.7% (95% CI, 7.4-8.1), respectively. The results also indicated that dementia and MCI share similar risk factors, including older age, female sex, hypertension, and diabetes mellitus. Compared with individuals with no formal education, those with > 6 years of education had an odds ratio for MCI of 1.83 (95% CI, 1.49-2.25). We also found that only 5.5% of the positive participants chose to be referred to the hospital for further diagnosis and treatment during follow-up visits. CONCLUSIONS: This study estimated the prevalence and risk factors for dementia and MCI among individuals aged ≥ 65 years in Southeast China. These findings are crucial for preventing and managing dementia and MCI in China.
Asunto(s)
Disfunción Cognitiva , Demencia , Humanos , Masculino , Femenino , Disfunción Cognitiva/epidemiología , Disfunción Cognitiva/diagnóstico , Anciano , China/epidemiología , Demencia/epidemiología , Demencia/diagnóstico , Prevalencia , Factores de Riesgo , Anciano de 80 o más AñosRESUMEN
A variety of compounds in Artemisia annua were simultaneously determined to evaluate the quality of A. annua from multiple perspectives. A method based on ultra-high performance liquid chromatography-triple quadrupole tandem mass spectrometry(UPLC-QQQ-MS/MS) was established for the simultaneous determination of seven compounds: amorpha-4,11-diene, artemisinic aldehyde, dihydroartemisinic acid, artemisinic acid, artemisinin B, artemisitene, and artemisinin, in A. annua. The content of the seven compounds in different tissues(roots, stems, leaves, and lateral branches) of A. annua were compared. The roots, stems, leaves, and lateral branches of four-month-old A. annua were collected and the content of seven artemisinin-related compounds in different tissues was determined. A multi-reaction monitoring(MRM) acquisition mode of UPLC-QQQ-MS/MS was used, with a positive ion mode of atmospheric pressure chemical ion source(APCI). Chromatographic separation was achieved on an Eclipse Plus RRHD C_(18) column(2.1 mm×50 mm, 1.8 µm). The gradient elution was performed with the mobile phase consisted of formic acid(0.1%)-ammonium formate(5 mmol·L~(-1))(A) and the methanol(B) gradient program of 0-8 min, 55%-100% B, 8-11 min, 100% B, and equilibrium for 3 min, the flow rate of 0.6 mL·min~(-1), the column temperature of 40 â, the injection volume of 5 µL, and the detection time of 8 min. Through methodological investigation, a method based on UPLC-QQQ-MS/MS was established for the simultaneous quantitative determination of seven representative compounds involved in the biosynthesis of artemisinin. The content of artemisinin in A. annua was higher than that of artemisinin B, and the content of artemisinin and dihydroartemisinic acid were high in all the tissues of A. annua. The content of the seven compounds varied considerably in different tissues, with the highest levels in the leaves and neither artemisinene nor artemisinic aldehyde was detected in the roots. In this study, a quantitative method based on UPLC-QQQ-MS/MS for the simultaneous determination of seven representative compounds involved in the biosynthesis of artemisinin was established, which was accurate, sensitive, and highly efficient, and can be used for determining the content of artemisinin-related compounds in A. annua, breeding new varieties, and controlling the quality of Chinese medicinal materials.
Asunto(s)
Artemisia annua , Artemisininas , Lactonas , Artemisia annua/química , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Fitomejoramiento , Artemisininas/análisis , AldehídosRESUMEN
In this study, antibody response and a single-cell RNA-seq analysis were conducted on peripheral blood mononuclear cells from five different groups: naïve subjects vaccinated with AZD1222 (AZ) or Ad5-nCoV (Cso), individuals previously infected and later vaccinated (hybrid) with AZD1222 (AZ-hb) or Ad5-nCoV (Cso-hb), and those who were infected and had recovered from COVID-19 (Inf). The results showed that AZ induced more robust neutralizing antibody responses than Cso. The single-cell RNA data revealed a high frequency of memory B cells in the Cso and Cso-hb. In contrast, AZ and AZ-hb groups exhibited the highest proportion of activated naïve B cells expressing CXCR4. Transcriptomic analysis of CD4+ and CD8+ T cells demonstrated a heterogeneous response following vaccination, hybrid immunity, or natural infection. However, a single dose of Ad5-nCoV was sufficient to strongly activate CD4+ T cells (naïve and memory) expressing ANX1 and FOS, similar to the hybrid response observed with AZ. An interesting finding was the robust activation of a subset of CD8+ T cells expressing GZMB, GZMH, and IFNG genes in the Cso-hb group. Our findings suggest that both vaccines effectively stimulated the cellular immune response; however, the Ad5-nCoV induced a more robust CD8+ T-cell response in previously infected individuals.
Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Humanos , Linfocitos T CD8-positivos , Adenoviridae/genética , ChAdOx1 nCoV-19 , Leucocitos Mononucleares , Perfilación de la Expresión Génica , Inmunidad Adaptativa , Anticuerpos Neutralizantes/genética , Anticuerpos Antivirales/genéticaRESUMEN
In this work, we formulate a random Wolbachia invasion model incorporating the effects of imperfect maternal transmission and incomplete cytoplasmic incompatibility (CI). Under constant environments, we obtain the following results: Firstly, the complete invasion equilibrium of Wolbachia does not exist, and thus the population replacement is not achievable in the case of imperfect maternal transmission; Secondly, imperfect maternal transmission or incomplete CI may obliterate bistability and backward bifurcation, which leads to the failure of Wolbachia invasion, no matter how many infected mosquitoes would be released; Thirdly, the threshold number of the infected mosquitoes to be released would increase with the decrease of the maternal transmission rate or the intensity of CI effect. In random environments, we investigate in detail the Wolbachia invasion dynamics of the random mosquito population model and establish the initial release threshold of infected mosquitoes for successful invasion of Wolbachia into the wild mosquito population. In particular, the existence and stability of invariant probability measures for the establishment and extinction of Wolbachia are determined.
Asunto(s)
Conceptos Matemáticos , Modelos Biológicos , Mosquitos Vectores , Wolbachia , Wolbachia/fisiología , Wolbachia/patogenicidad , Animales , Femenino , Mosquitos Vectores/microbiología , Dinámica Poblacional/estadística & datos numéricos , Citoplasma/microbiología , Culicidae/microbiología , Masculino , Simulación por Computador , Herencia MaternaRESUMEN
The controllable construction of complex metal-organic coordination polymers (CPs) merits untold scientific and technological potential, yet remains a grand challenge of one-step construction and modulating simultaneously valence states of metals and topological morphology. Here, a thiocyanuric acid (TCA)-triggered strategy is presented to one-step rapid synthesis a double-crystalline Prussian blue analogue hetero-superstructure (PBA-hs) that comprises a Co3[Fe(CN)6]2 cube overcoated with a KCo[Fe(CN)6] shell, followed by eight self-assembled small cubes on vertices. Unlike common directing surfactants, TCA not only acts as a trigger for the fast growth of KCo[Fe(CN)6] on the Co3[Fe(CN)6]2 phase resulting in a PBA-on-PBA hetero-superstructure, but also serves as a flange-like bridge between them. By combining experiments with simulations, a deprotonation-induced electron transfer (DIET) mechanism is proposed for formation of second phase in PBA-hs, differing from thermally and photo-induced electron transfer processes. To prove utility, the calcined PBA-hs exhibits enhanced oxygen evolution reaction performance. This work provides a new method to design of novel CPs for enriching chemistry and material science. This work offers a practical approach to design novel CPs for enriching chemistry and material science.
RESUMEN
Catalytic performance of single-atom catalysts (SACs) relies fundamentally on the electronic nature and local coordination environment of the active site. Here, based on a machine-learning (ML)-aided density functional theory (DFT) method, we reveal that the intrinsic dipole in Janus materials has a significant impact on the catalytic activity of SACs, using 2D γ-phosphorus carbide (γ-PC) as a model system. Specifically, a local dipole around the active site is a key degree to tune the catalytic activity and can be used as an important descriptor with a high feature importance of 17.1% in predicting the difference of adsorption free energy (ΔGO* - ΔGOH*) to assess the activity of the oxygen evolution reaction. As a result, the catalytic performance of SACs can be tuned by an intrinsic dipole, in stark contrast to those external stimuli strategies previously used. These results suggest that dipole engineering and the revolutionary DFT-ML hybrid scheme are novel approaches for designing high-performance catalysts.
RESUMEN
BACKGROUND: Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can lead to severe disease with increased morbidity and mortality among certain risk groups. The presence of autoantibodies against type I interferons (aIFN-Abs) is one mechanism that contributes to severe coronavirus disease 2019 (COVID-19). METHODS: This study aimed to investigate the presence of aIFN-Abs in relation to the soluble proteome, circulating immune cell numbers, and cellular phenotypes, as well as development of adaptive immunity. RESULTS: aIFN-Abs were more prevalent in critical compared to severe COVID-19 but largely absent in the other viral and bacterial infections studied here. The antibody and T-cell response to SARS-CoV-2 remained largely unaffected by the presence aIFN-Abs. Similarly, the inflammatory response in COVID-19 was comparable in individuals with and without aIFN-Abs. Instead, presence of aIFN-Abs had an impact on cellular immune system composition and skewing of cellular immune pathways. CONCLUSIONS: Our data suggest that aIFN-Abs do not significantly influence development of adaptive immunity but covary with alterations in immune cell numbers.
Asunto(s)
Autoanticuerpos , COVID-19 , Interferón Tipo I , SARS-CoV-2 , Humanos , COVID-19/inmunología , Interferón Tipo I/inmunología , Autoanticuerpos/sangre , Autoanticuerpos/inmunología , SARS-CoV-2/inmunología , Masculino , Femenino , Persona de Mediana Edad , Inmunidad Celular , Adulto , Anciano , Inmunidad Adaptativa/inmunología , Linfocitos T/inmunología , Índice de Severidad de la EnfermedadRESUMEN
Postoperative cognitive dysfunction (POCD) commonly occurs after surgery, particularly in elderly individuals. It is characterized by a notable decline in cognitive performance, encompassing memory, attention, coordination, orientation, verbal fluency, and executive function. This reduction in cognitive abilities contributes to extended hospital stays and heightened mortality. The prevalence of POCD can reach 40% within 1 week following cardiovascular surgery and remains as high as 17% 3 months post-surgery. Furthermore, POCD exacerbates the long-term risk of Alzheimer's disease (AD). As a result, numerous studies have been conducted to investigate the molecular mechanisms underlying POCD and potential preventive strategies. This article provides a review of the research progress on POCD.
RESUMEN
MOTIVATION: Cell-type annotation of single-cell RNA-sequencing (scRNA-seq) data is a hallmark of biomedical research and clinical application. Current annotation tools usually assume the simultaneous acquisition of well-annotated data, but without the ability to expand knowledge from new data. Yet, such tools are inconsistent with the continuous emergence of scRNA-seq data, calling for a continuous cell-type annotation model. In addition, by their powerful ability of information integration and model interpretability, transformer-based pre-trained language models have led to breakthroughs in single-cell biology research. Therefore, the systematic combining of continual learning and pre-trained language models for cell-type annotation tasks is inevitable. RESULTS: We herein propose a universal cell-type annotation tool, called CANAL, that continuously fine-tunes a pre-trained language model trained on a large amount of unlabeled scRNA-seq data, as new well-labeled data emerges. CANAL essentially alleviates the dilemma of catastrophic forgetting, both in terms of model inputs and outputs. For model inputs, we introduce an experience replay schema that repeatedly reviews previous vital examples in current training stages. This is achieved through a dynamic example bank with a fixed buffer size. The example bank is class-balanced and proficient in retaining cell-type-specific information, particularly facilitating the consolidation of patterns associated with rare cell types. For model outputs, we utilize representation knowledge distillation to regularize the divergence between previous and current models, resulting in the preservation of knowledge learned from past training stages. Moreover, our universal annotation framework considers the inclusion of new cell types throughout the fine-tuning and testing stages. We can continuously expand the cell-type annotation library by absorbing new cell types from newly arrived, well-annotated training datasets, as well as automatically identify novel cells in unlabeled datasets. Comprehensive experiments with data streams under various biological scenarios demonstrate the versatility and high model interpretability of CANAL. AVAILABILITY: An implementation of CANAL is available from https://github.com/aster-ww/CANAL-torch. CONTACT: dengmh@pku.edu.cn. SUPPLEMENTARY INFORMATION: Supplementary data are available at Journal Name online.
Asunto(s)
Perfilación de la Expresión Génica , Programas Informáticos , Perfilación de la Expresión Génica/métodos , Análisis de Expresión Génica de una Sola Célula , Análisis de la Célula Individual/métodos , Lenguaje , Análisis de Secuencia de ARN/métodosRESUMEN
Photocatalytic reduction of carbon dioxide is a technology that effectively utilizes CO2and solar energy. Sodium niobate (NaNbO3) has received much attention in the field of photocatalysis due to its excellent photocatalytic properties. However, the application of NaNbO3in the field of photocatalysis is still limited by poor reaction to visible light and easy recombination of photo-generated carriers. Heterojunction with g-C3N4to construct core-shell structure can effectively improve the above problems. Combining the two can design a core-shell composite material that is beneficial for photocatalytic reduction of CO2. Herein, we prepared a core-shell heterojunction g-C3N4/NaNbO3by uniformly impregnating urea on the surface of NaNbO3chromium nanofibers with NaNbO3nanofibers prepared by electrospinning as a catalyst carrier, and urea as a precursor of g-C3N4. The core-shell structure of g-C3N4/NaNbO3was verified by a series of characterization methods such as XPS, XRD, and TEM. It was found that under the same conditions, the methanol yield of core-shell g-C3N4/NaNbO3was 12.86µmol·g-1·h-1, which is twice that of pure NaNbO3(6.67µmol·g-1·h-1). This article highlights an impregnation method to build core-shell structures for improved photocatalytic reduction of CO2.
RESUMEN
It is widely accepted that prevéraison application of naphthaleneacetic acid (NAA) can delay the ripening of grapes and improve their quality. However, how NAA impacts grape aroma compound concentrations remains unclear. This study incorporated the analyses of aroma metabolome, phytohormones, and transcriptome of Vitis vinifera L. cv. Cabernet Sauvignon grapes cultivated in continental arid/semiarid regions of western China. The analyses demonstrated that NAA application increased ß-damascenone and 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN) in the harvested grapes by delaying véraison and upregulating VvPSY1 and VvCCD4b expressions. Additionally, NAA treatment decreased 2-isobutyl-3-methoxypyrazine (IBMP) at the same phenological stage. Notably, abscisic acid (ABA) levels increased in NAA-treated grapes during véraison, which triggered further changes in norisoprenoid metabolisms. The ABA-responsive factor VvABF2 was potentially involved in VvPSY1 positive modulation, while the auxin response factor VvARF10 may play a role in VvCCD4b upregulation and VvOMT2 downregulation during NAA induction. VvARF10 possibly acts as a crosstalk node between the ABA and auxin signaling pathways following NAA treatment in regulating aroma biosynthesis.