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1.
Nature ; 628(8006): 78-83, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38538799

RESUMO

Exotic physics could emerge from interplay between geometry and correlation. In fractional quantum Hall (FQH) states1, novel collective excitations called chiral graviton modes (CGMs) are proposed as quanta of fluctuations of an internal quantum metric under a quantum geometry description2-5. Such modes are condensed-matter analogues of gravitons that are hypothetical spin-2 bosons. They are characterized by polarized states with chirality6-8 of +2 or -2, and energy gaps coinciding with the fundamental neutral collective excitations (namely, magnetorotons9,10) in the long-wavelength limit. However, CGMs remain experimentally inaccessible. Here we observe chiral spin-2 long-wavelength magnetorotons using inelastic scattering of circularly polarized lights, providing strong evidence for CGMs in FQH liquids. At filling factor v = 1/3, a gapped mode identified as the long-wavelength magnetoroton emerges under a specific polarization scheme corresponding to angular momentum S = -2, which persists at extremely long wavelength. Remarkably, the mode chirality remains -2 at v = 2/5 but becomes the opposite at v = 2/3 and 3/5. The modes have characteristic energies and sharp peaks with marked temperature and filling-factor dependence, corroborating the assignment of long-wavelength magnetorotons. The observations capture the essentials of CGMs and support the FQH geometrical description, paving the way to unveil rich physics of quantum metric effects in topological correlated systems.

2.
Nano Lett ; 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39377299

RESUMO

Lithium metal batteries are booming because of their inherent preponderance, but a negative electric field from concentration dipolarization and slow solid-phase transfer at the electrode interface become blocking modules for extreme fast charging. Achieving an anion-rich solvation shell with a high dielectric constant (ε) is a feasible strategy to bootstrap an interface microenvironment for mass-transport reaction, but it is still an uncultivated field. Herein, the superposition, including the donor number values, the high ε, and the spatial potential resistance, are complementarily considered; we propose a low-cost electrolyte with an internal excluding external tactic to answer the above issue. Explanatorily, an optimized solvation shell follows the cascading exclusion relationship of nitrate ion (NO3-) → tetraglyme → ethylene carbonate → dimethyl carbonate. And the culminated bilayer structure establishes ideal conditions for Li+ transfer-reaction kinetics, of which an anion-rich internal shell facilitates solid-phase transport and a high-ε external shell slashes the negative electric field.

3.
Biochem Biophys Res Commun ; 735: 150669, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39260336

RESUMO

CDK5 plays a crucial role in maintaining normal central nervous system (CNS) development and synaptic function, while microglia are the primary immune cells present in the CNS and play vital physiological roles in CNS development, immune surveillance, and regulation of synaptic plasticity. Despite this, our understanding of both the substrate proteins and functional mechanisms of CDK5 in microglia remains limited. To address this, we utilized CRISPR-Cas9 knockout of Cdk5 in BV2 cells and conducted quantitative phosphoproteomics analysis to systematically screen potential CDK5 substrates in microglia. Our findings identified 335 phosphorylation sites on 234 proteins as potential CDK5 substrates in microglia based on the reported sequence motif. Through in vitro kinase assay and intracellular inhibition and knockout of CDK5 experiments, we confirmed that ER proteins MTDH (protein LYRIC) and Calnexin are novel substrate proteins of CDK5. Moreover, we demonstrated for the first time a critical mechanism for regulating protein synthesis in microglia, that the phosphorylation of S565 site on MTDH, a key protein mediating cell growth, by CDK5 inhibits protein synthesis. Our data provide valuable insights for the discovery of new substrate proteins of CDK5 and the in-depth investigation of the function and mechanism of CDK5 in microglia.

4.
Opt Express ; 32(4): 6507-6519, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439351

RESUMO

With the increasing demand for communication capacity, all-optical regeneration of multimode signals is a helpful technology of network nodes and optical signal processors. However, the difficulty of regenerating signal in higher-order modes hinders the practical application of multimode all-optical regenerators. In this study, we experimentally demonstrate the 40 Gb/s all-optical regeneration of NRZ-OOK signal in TE0 and TE1 modes via four-wave mixing (FWM) in the low-loss silicon-based nanowaveguide. By optimizing the parameters of waveguide section to enhance FWM conversion efficiency of two modes, and introducing Euler bending to reduce crosstalk between modes, the transmission loss of the silicon waveguide is 0.3 dB/cm, and the FWM conversion efficiency of the multimode regenerator is as high as -9.6 dB (TE0) and -13.0 dB (TE1). Both modes achieve extinction ratio enhancement of about 6 dB after regeneration. This silicon-based all-optical regenerator has great application potential in all-optical signal processing systems.

5.
Inflamm Res ; 73(9): 1547-1564, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39008037

RESUMO

BACKGROUND: Microglia, the main innate immune cells in the central nervous system, are key drivers of neuroinflammation, which plays a crucial role in the pathogenesis of neurodegenerative diseases. The Sin3/histone deacetylase (HDAC) complex, a highly conserved multiprotein co-repressor complex, primarily performs transcriptional repression via deacetylase activity; however, the function of SDS3, which maintains the integrity of the complex, in microglia remains unclear. METHODS: To uncover the regulatory role of the transcriptional co-repressor SDS3 in microglial inflammation, we used chromatin immunoprecipitation to identify SDS3 target genes and combined with transcriptomics and proteomics analysis to explore expression changes in cells following SDS3 knocking down. Subsequently, we validated our findings through experimental assays. RESULTS: Our analysis revealed that SDS3 modulates the expression of the upstream kinase ASK1 of the p38 MAPK pathway, thus regulating the activation of signaling pathways and ultimately influencing inflammation. CONCLUSIONS: Our findings provide important evidence of the contributions of SDS3 toward microglial inflammation and offer new insights into the regulatory mechanisms of microglial inflammatory responses.


Assuntos
Inflamação , MAP Quinase Quinase Quinase 5 , Microglia , Proteínas Repressoras , Proteínas Quinases p38 Ativadas por Mitógeno , Animais , Humanos , Camundongos , Linhagem Celular , Inflamação/metabolismo , MAP Quinase Quinase Quinase 5/metabolismo , MAP Quinase Quinase Quinase 5/genética , Sistema de Sinalização das MAP Quinases , Microglia/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Transdução de Sinais , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
6.
World J Surg ; 48(6): 1440-1447, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38733313

RESUMO

BACKGROUND: Thyroid cancer diagnoses have increased over recent decades at a rate much higher than that of any other cancer in Australia. Rural patients are known to have reduced access to healthcare and may have different thyroid cancer presentation rates. This study examined the relationship between thyroid cancer diagnosis and patient rurality. METHODS: Data from the Australia and New Zealand Thyroid Cancer Registry from 2017 to 2022 were analyzed, stratifying patient postcodes into rurality groups using the Australian Statistical Geography Standard. The American Thyroid Association (ATA) guidelines were used to stratify risk categories and management to compare treatment adequacy between the groups. Statistical analysis assessed demographic, clinical, and management differences. RESULTS: Among 1766 patients, 70.6% were metropolitan (metro) and 29.4% were non-metropolitan (non-metro). Non-metro patients were older at diagnosis (median 56 vs. 50 years, p < 0.001), presented more frequently with T stage greater than 1 (stage 2-4, 41.9% vs. 34.8%, and p = 0.005), AJCC stage greater than 1 (stage 2-4, 18.5% vs. 14.6%, and p = 0.019), and cancers larger than 4 cm (14.3% vs. 9.9%, p = 0.005). No significant differences in treatment adequacy were observed between the groups for ATA low-risk cancers. CONCLUSIONS: Non-metropolitan patients in the registry present with more advanced thyroid cancer, possibly due to differences in healthcare access. Further research should assess long-term survival outcomes and influencing factors. Understanding the impact on patient outcomes and addressing healthcare access barriers can optimize thyroid cancer care across geographic regions in Australia.


Assuntos
Disparidades em Assistência à Saúde , Estadiamento de Neoplasias , Sistema de Registros , População Rural , Neoplasias da Glândula Tireoide , Humanos , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/terapia , Neoplasias da Glândula Tireoide/mortalidade , Neoplasias da Glândula Tireoide/diagnóstico , Feminino , Pessoa de Meia-Idade , Austrália , Masculino , Adulto , População Rural/estatística & dados numéricos , Disparidades em Assistência à Saúde/estatística & dados numéricos , Idoso , Nova Zelândia/epidemiologia , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos
7.
PLoS Genet ; 17(12): e1009586, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34941903

RESUMO

The cell envelope is essential for viability in all domains of life. It retains enzymes and substrates within a confined space while providing a protective barrier to the external environment. Destabilising the envelope of bacterial pathogens is a common strategy employed by antimicrobial treatment. However, even in one of the best studied organisms, Escherichia coli, there remain gaps in our understanding of how the synthesis of the successive layers of the cell envelope are coordinated during growth and cell division. Here, we used a whole-genome phenotypic screen to identify mutants with a defective cell envelope. We report that loss of yhcB, a conserved gene of unknown function, results in loss of envelope stability, increased cell permeability and dysregulated control of cell size. Using whole genome transposon mutagenesis strategies, we report the comprehensive genetic interaction network of yhcB, revealing all genes with a synthetic negative and a synthetic positive relationship. These genes include those previously reported to have a role in cell envelope biogenesis. Surprisingly, we identified genes previously annotated as essential that became non-essential in a ΔyhcB background. Subsequent analyses suggest that YhcB functions at the junction of several envelope biosynthetic pathways coordinating the spatiotemporal growth of the cell, highlighting YhcB as an as yet unexplored antimicrobial target.


Assuntos
Parede Celular/genética , Proteínas de Escherichia coli/genética , Lipopolissacarídeos/genética , Oxirredutases/genética , Peptidoglicano/genética , Divisão Celular/genética , Membrana Celular/genética , Membrana Celular/microbiologia , Parede Celular/microbiologia , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica/genética , Lipopolissacarídeos/biossíntese , Mutagênese , Fosfolipídeos/biossíntese , Fosfolipídeos/genética
8.
J Environ Manage ; 353: 120181, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38271882

RESUMO

The substantial development of the dyeing and printing industry has resulted in an increased discharge of dye wastewater containing a large amount of recalcitrant organic pollutants. Furthermore, the landfill disposal of red mud has led to significant environmental pollution such as soil erosion and groundwater contamination. Therefore, this study aimed to promote the resource utilization of red mud by preparing advanced oxidation catalyst, resulting in effective treatment of dye wastewater, and the primary reaction mechanism was revealed. In this study, biochar-loading red mud (RBC) was applied to activate persulfate (PDS) for the degradation of acid orange 7 (AO7) with the initial concentration of 50 mg L-1. The maximum removal rate of 2.45 mg L·min-1 was achieved in 20 min and corresponding with the removal ratio of 98.0% under the PDS concentration of 20 mM (4.76 g L-1). Eventually, the removal ratio of 99.2% was attained within 60 min. The high catalytic efficiency was probably ascribed to the singlet oxygen (1O2) dominant non-radical pathway and RBC-mediated electron transfer mechanism. It was found that Fe(II), specific surface areas and functional groups on the catalyst were highly related to its catalytic efficiency and passivation. RBC had better reusability due to the loading of biochar and the reduction of zero-valent iron. The non-radical pathway mechanism and electron transfer mechanism were proposed for the activation of PDS, and non-radical pathway played a dominant role. Besides, the degradation pathways and toxicity assessment were analyzed. This research proposed a new electron transfer mechanism for activation process of PDS, which can provide a theoretical support for further studies. Overall, this study demonstrated that catalysts synthesized from red mud and biomass exhibit highly efficient activation in degrading the model pollutant AO7 through PDS activation. The catalyst displayed promising reusability and practical applicability, offering potential advancements in both the resource utilization and reduction of red mud.


Assuntos
Compostos Azo , Benzenossulfonatos , Poluentes Ambientais , Poluentes Químicos da Água , Águas Residuárias , Carvão Vegetal , Ferro , Poluentes Químicos da Água/análise
9.
BMC Bioinformatics ; 24(1): 110, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36959539

RESUMO

BACKGROUND: Drug‒drug interactions (DDIs) are reactions between two or more drugs, i.e., possible situations that occur when two or more drugs are used simultaneously. DDIs act as an important link in both drug development and clinical treatment. Since it is not possible to study the interactions of such a large number of drugs using experimental means, a computer-based deep learning solution is always worth investigating. We propose a deep learning-based model that uses twin convolutional neural networks to learn representations from multimodal drug data and to make predictions about the possible types of drug effects. RESULTS: In this paper, we propose a novel convolutional neural network algorithm using a Siamese network architecture called CNN-Siam. CNN-Siam uses a convolutional neural network (CNN) as a backbone network in the form of a twin network architecture to learn the feature representation of drug pairs from multimodal data of drugs (including chemical substructures, targets and enzymes). Moreover, this network is used to predict the types of drug interactions with the best optimization algorithms available (RAdam and LookAhead). The experimental data show that the CNN-Siam achieves an area under the precision-recall (AUPR) curve score of 0.96 on the benchmark dataset and a correct rate of 92%. These results are significant improvements compared to the state-of-the-art method (from 86 to 92%) and demonstrate the robustness of the CNN-Siam and the superiority of the new optimization algorithm through ablation experiments. CONCLUSION: The experimental results show that our multimodal siamese convolutional neural network can accurately predict DDIs, and the Siamese network architecture is able to learn the feature representation of drug pairs better than individual networks. CNN-Siam outperforms other state-of-the-art algorithms with the combination of data enhancement and better optimizers. But at the same time, CNN-Siam has some drawbacks, longer training time, generalization needs to be improved, and poorer classification results on some classes.


Assuntos
Aprendizado Profundo , Tailândia , Redes Neurais de Computação , Algoritmos , Interações Medicamentosas
10.
Microbiology (Reading) ; 169(11)2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37909267

RESUMO

Genetic screens are a key tool for linking phenotype and genotype. Transposon mutagenesis was one of the first genetic methodologies to associate genetic loci with phenotypes. The advent of next-generation sequencing transformed the use of this technique allowing rapid interrogation of whole genomes for genes that correlate with phenotype. One method is transposon directed insertion-site sequencing (TraDIS). Here we describe the method, recent developments in technology, and the advantages and disadvantages of this method compared to other genetic screening tools.


Assuntos
Elementos de DNA Transponíveis , Sequenciamento de Nucleotídeos em Larga Escala , Elementos de DNA Transponíveis/genética , Mutagênese , Fenótipo , Genótipo , Sequência de Bases , Mutagênese Insercional , Sequenciamento de Nucleotídeos em Larga Escala/métodos
11.
Small ; 19(7): e2206403, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36504361

RESUMO

The airborne particulate matter (PM) seriously threatens people's health. Personal protective equipment with electrospun nanofibers is an effective method to make people away from air pollutants. Herein, 3D waterproof melamine-formaldehyde polyvinyl alcohol (MF-PVA) nanofibrous membranes are fabricated by a one-step method combining multi-unit needleless electrospinning and a thermal treatment device in a line. 3D nanofibrous structures can be controlled by adjusting the solution concentration of each unit. The PVA nanofibrous membranes become waterproof after cross-linking with MF resin in the following thermal treatment device. The optimized MF-PVA nanofibrous membrane shows excellent air filtration performance (97.3% for PM0.3 , 100% for PM1.0 , and 100% for PM2.5 ) and low air resistance (76 Pa). These 3D waterproof MF-PVA nanofibrous membranes exhibit ultra-stable performance in various practical environments.

12.
J Pediatr Hematol Oncol ; 45(2): e266-e271, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36730964

RESUMO

We described a 14-year-old girl with acute lymphoblastic leukemia who developed disseminated mucormycosis during induction therapy. Disseminated Cunninghamella elegans infection was confirmed by histopathology, microbiological culture, and metagenomic next-generation sequencing analysis of skin tissue, blood, and cerebrospinal fluid. Subsequently, the patient received a combination of liposomal amphotericin B, posaconazole, and caspofungin for antifungal treatment, but eventually died because of severe fungal pneumonia, respiratory failure, and septic shock. Moreover, case reports of pulmonary mucormycosis in children published since 1959 were reviewed. In summary, metagenomic next-generation sequencing is an effective diagnostic method for Cunninghamella with high speed and sensitivity.


Assuntos
Cunninghamella , Mucormicose , Leucemia-Linfoma Linfoblástico de Células Precursoras , Feminino , Humanos , Criança , Adolescente , Mucormicose/tratamento farmacológico , Quimioterapia de Indução , Antifúngicos/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico
13.
Biochem Genet ; 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38063952

RESUMO

Breast cancer is a common cancer worldwide. Hyperplastic enlarged lobular units (HELUs) are common changes in the breasts of adult women. HELUs may be closely related to the occurrence and development of breast cancer. In this study, genes that are commonly contained in the expression profiles of the genomes of the two diseases and have significant differences in expression before and after the respective diseases were identified. Various enrichment analyses were performed according to the expression levels of these differentially expressed genes. Furthermore, LASSO regression analysis was performed on the differentially expressed genes to identify genes significantly related to survival. The optimal risk model for the survival of patients with breast cancer was established, and the accuracy of the model was verified on multiple data sets. A gene combination containing 17 genes was ultimately determined to be an independent prognostic factor. Kaplan‒Meier survival analysis demonstrated the good performance of this risk model. The study found that Shared Gene Signatures and Biological Mechanisms in Hyperplastic Enlarged Lobular Units and Breast Cancer, screened 17 important Shared Gene Signatures of Hyperplastic Enlarged Lobular Units which are closely related to the survival of breast cancer patients through machine learning, and established a prognosis model with high-accuracy, which is worthy of further exploration.

14.
Int J Mol Sci ; 24(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37446049

RESUMO

Coronavirus disease 2019 (COVID-19) threatens public health all over the world. It is well-accepted that the immune cells in peripheral blood are widely involved in the pathological process of COVID-19. However, hematopoietic stem and progenitor cells (HSPCs), as the main source of peripheral immune cells, have not been well studied during COVID-19 infection. We comprehensively revealed the transcriptome changes of peripheral blood HSPCs after COVID-19 infection and vaccination by single-cell RNA-seq. Compared with healthy individuals, the proportion of HSPCs in COVID-19 patients significantly increased. The increase in the proportion of HSPCs might be partly attributed to the enhancement of the HSPCs proliferation upon COVID-19 infection. However, the stemness damage of HSPCs is reflected by the decrease of differentiation signal, which can be used as a potential specific indicator of the severity and duration of COVID-19 infection. Type I interferon (IFN-I) and translation signals in HSPCs were mostly activated and inhibited after COVID-19 infection, respectively. In addition, the response of COVID-19 vaccination to the body is mild, while the secondary vaccination strengthens the immune response of primary vaccination. In conclusion, our study provides new insights into understanding the immune mechanism of COVID-19 infection.


Assuntos
COVID-19 , Transcriptoma , Humanos , Vacinas contra COVID-19 , Análise da Expressão Gênica de Célula Única , Células-Tronco Hematopoéticas
15.
J Environ Manage ; 347: 119077, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37776788

RESUMO

In this study, a novel acid-modified red mud biochar catalyst (MMBC) was synthesized by industrial waste red mud (RM) and peanut shell (PSL) to activate peroxodisulfate (PDS) for the degradation of TC. Meanwhile, MMBC exhibited remarkable adsorption capacity, reaching a 60% removal ratio of TC within 60 min (equilibrium adsorption capacity = 12 mg/g). After adding PDS, MMBC/PDS system achieved a 93.8% removal ratio of TC within 60 min. Quenching experiments and electron paramagnetic resonance (EPR) results showed that 1O2 played a dominant role in the degradation of TC and O2•- was the mainly precursor for the production of 1O2 in the MMBC/PDS system. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) analysis showed that the surface Fe(II), -OH and -COOH provided the active sites for the activation of PDS by MMBC. In addition, acid modification optimised the surface structure of the catalyst and enhanced the conversion of Fe (mainly Fe(III) to Fe(II)), thereby improving the adsorption and catalytic efficiency of MMBC. This study confirmed that modified red mud biochar is an efficient composite with both adsorption and catalysis, providing new ideas for the practical treatment of antibiotic wastewater and the resource utilization of red mud.


Assuntos
Compostos Férricos , Poluentes Químicos da Água , Compostos Férricos/química , Adsorção , Carvão Vegetal/química , Antibacterianos , Tetraciclina , Compostos Ferrosos , Poluentes Químicos da Água/química
16.
Molecules ; 28(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38138456

RESUMO

Apples are rich in vitamins and dietary fiber and are one of the essential fruits in people's daily diet. China has always been a big apple consumer, and with the improvement of people's life quality, nutrition, and health requirements, the demand for high-quality apples has increased year by year. Apple mold heart disease is one of the main diseases affecting apple quality. However, this disease cannot be easily detected from the surface, so it is difficult to detect mold heart disease. Therefore, this paper focuses on the analysis of seven non-destructive detection technologies, including near infrared spectroscopy technology, hyperspectral technology, Raman spectroscopy technology, electronic nose technology, acoustic technology, electrical technology, and magnetic technology, summarizes their application status in the detection of apple mold heart disease, and then analyzes their advantages and disadvantages. Combined with the current rapid development of artificial intelligence (AI) technology, this paper proposes the future development trends of using non-destructive technologies to detect apple mold heart disease. It is expected to provide basic theory and application references for the intelligent detection of apple mold heart disease.


Assuntos
Cardiopatias , Malus , Humanos , Inteligência Artificial , Fungos , Cardiopatias/diagnóstico , Tecnologia
17.
Small ; 18(25): e2201343, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35608317

RESUMO

The electrocatalytic nitrogen reduction reaction (NRR) is a promising approach for renewable ammonia synthesis but remains significantly challenging due to the low yield and poor selectivity. Herein, a facile N and S dual anions substitution strategy is developed to tune the Ti oxidation states of TiO2 nanohybrid catalyst (NS-TiO2 /C), in which anatase TiO2 nanoplates with dense Ti3+ active sites are uniformly dispersed on porous carbon derived from 2D Ti3 C2 Tx nanosheets. The catalyst NS-TiO2 /C exhibits a superior ambient NRR efficiency with an NH3 yield rate of 19.97 µg h-1 mg-1cat and Faradaic efficiency of 25.49% and is coupled with a remarkable 50 h long-term stability at -0.25 V versus RHE. Both experimental and theoretical results reveal that the N and S dual-substitution effectively regulate the Ti oxidation state and electronical properties of the NS-TiO2 /C via simultaneously forming interstitial and substitutional TiS and TiN bonds in the anatase TiO2 lattice, inducing oxygen vacancies and dense Ti3+ active species as well as better electronic conductivity, which substantially facilitates N2 chemisorption and activation, and reduces the energy barrier of the rate-determining step, thereby essentially boosting NRR efficiency. This work provides a valuable approach to the rational design of advanced materials by modulating oxidation states for efficient electrocatalysis.


Assuntos
Carbono , Titânio , Ânions , Carbono/química , Catálise , Nitrogênio/química
18.
Small ; 18(14): e2107250, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35166038

RESUMO

Particulate matter (PM) pollution has become a serious environmental concern. Nanofibrous filters are widely reported to remove PM from polluted air. Herein, efficient and lightweight PM air filters are presented using airflow synergistic needleless electrospinning composed of auxiliary fields such as an airflow field and a secondary inductive electric field. Compared to needleless electrospinning with other spinnerets, it significantly improves productivity, fiber diameter, and porosity of fibrous air filters. The instant noodle-like nanofiber structure can also be controlled by adjusting the airflow velocity. These air filters exhibit high (2.5 µm particulate matter) PM2.5 removal efficiency (99.9%) and high (0.3 µm particulate matter) PM0.3 removal efficiency (99.1%), low pressure drop (56 Pa for PM2.5 and 78 Pa for PM0.3 ), and large dust holding capacitance (the maximum value is 168 g m-2 for PM2.5 , while 102 g m-2 for PM0.3 ). Meanwhile, the proposed PM filters are also tested suitable and stable to other polluted air filtrations such as cigarette smoke and sawdust. The large-scale synthesis of such an attractive nanofiber structure presents the great potential of high-performance filtration/separation materials.


Assuntos
Filtros de Ar , Nanofibras , Filtração , Material Particulado , Porosidade
19.
J Ultrasound Med ; 41(5): 1101-1108, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34382236

RESUMO

OBJECTIVES: Intravenous leiomyomatosis (IVL) is a histologically benign but biologically aggressive tumor. This study aimed to summarize the echocardiography and contrast-enhanced ultrasound (CEU) characteristics of IVL to provide a basis for clinical diagnosis and therapy. METHODS: Fourteen IVL patients with uterus leiomyoma history (female, 46.4 ± 5.6 years) were enrolled in this study from March 2008 to December 2020 in our hospital. Preoperative imaging examination data were collected, including echocardiography computed tomography data; six patients also underwent CEU. All patients underwent successful resection, confirmed by histopathology. RESULTS: Echocardiographic characteristics: The mean sizes of intracardiac parts of IVL tumors were 54.0 ± 17.9 mm (length) and 24.6 ± 9.8 mm (width). IVL tumors exhibited two echocardiography types: isoechoic solid mass (71.4%, 10/14) and anechoic cystic conduits (28.6%, 4/14), with enlargements of the right atrium (57.1%,8/14), right ventricle (1 patient, 7.1%), and inferior vena cava (57.1%, 8/14). About 21.4% of the patients (3/14) had right ventricular dysfunction. Right heart obstruction was observed in 42.8% (6/14) of the patients. CEU characteristics: the solid mass type exhibited an earlier perfusion and lower perfusion intensity than the conduits type. CEU was helpful in determining origins and pathways: from the internal iliac vein (pathway I, 71.4%), from the ovarian vein (pathway II, 14.3%), or both (14.3%). The echocardiographic appearances of the 14 cases were consistent with the features of the resection specimens. CONCLUSION: Combined echocardiography and CEU can provide a more valuable information for the diagnosis of IVL and essential basis for treatment.


Assuntos
Neoplasias Cardíacas , Leiomiomatose , Neoplasias Uterinas , Neoplasias Vasculares , Ecocardiografia , Feminino , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/patologia , Neoplasias Cardíacas/diagnóstico por imagem , Neoplasias Cardíacas/patologia , Neoplasias Cardíacas/cirurgia , Humanos , Leiomiomatose/diagnóstico por imagem , Leiomiomatose/patologia , Leiomiomatose/cirurgia , Neoplasias Uterinas/diagnóstico por imagem , Neoplasias Uterinas/cirurgia , Neoplasias Vasculares/diagnóstico por imagem , Neoplasias Vasculares/patologia , Neoplasias Vasculares/cirurgia , Veia Cava Inferior/diagnóstico por imagem
20.
Soft Matter ; 17(5): 1428-1436, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33325964

RESUMO

Recently, inclusion complexes formed from cyclodextrins (CDs) and surfactants have been found to play complex and important roles in supramolecular self-assembly. In this work, the self-assembly of perfluorononanoic acid (PFNA)/γ-cyclodextrin (γ-CD) in aqueous solution was investigated. The sole PFNA solution assembled into spherical uni-lamellar vesicles under certain concentrations as revealed by freeze-fracture transmission electron microscopy (FF-TEM) images. Interestingly, when γ-CD was added into the PFNA solution, one novel kind of cyclodextrin-based hydrogel with a crystal-like structure was obtained. The morphology of the hydrogels was inerratic parallel hexahedron or regular hexahedron as revealed by optical microscopy and scanning electron microscopy (SEM) measurements. Furthermore, the hydrogels were transformed into crystalline precipitates, which were composed of highly uniform tetragonal sheets with excellent crystallinity and homogeneous size distribution just by changing the γ-CD concentration. More amazingly, the crystal-like hydrogels were sensitive to shear and switched to solutions in their morphology with bar-like and rod-like aggregates and smaller square sheets under different shear rates, and the hydrogel-solution transition behavior was a reversable process. 1H NMR, Fourier transform infrared (FT-IR) and wide-angle X-ray diffraction (WXRD) measurements were performed to lead us to propose the formation mechanism of the above aggregates. Hopefully, our studies will cast new light on the fundamental investigations into the self-assembly of supramolecular systems of fluorinated surfactants and CD molecules and provide a new idea for smart material design.

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