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1.
Nat Commun ; 15(1): 6827, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39122681

RESUMO

Developing high-performance Pt-based catalysts with low Pt loading is crucial but challenging for CO oxidation at temperatures below 100 °C. Herein, we report a Pt-based catalyst with only a 0.15 wt% Pt loading, which consists of Pt-Ti intermetallic single-atom alloy (ISAA) and Pt nanoparticles (NP) co-supported on a defective TiO2 support, achieving a record high turnover frequency of 11.59 s-1 at 80 °C and complete conversion of CO at 120 °C. This is because the coexistence of Pt-Ti ISAA and Pt NP significantly alleviates the competitive adsorption of CO and O2, enhancing the activation of O2. Furthermore, Pt single atom sites are stabilized by Pt-Ti ISAA, resulting in distortion of the TiO2 lattice within Pt-Ti ISAA. This distortion activates the neighboring surface lattice oxygen, allowing for the simultaneous occurrence of the Mars-van Krevelen and Langmuir-Hinshelwood reaction paths at low temperatures.

2.
ACS Nano ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39106474

RESUMO

Hydrophones play a crucial role in underwater target detection within sonar systems. However, existing hydrophones often encounter challenges such as low sensitivity and poor signal-to-noise ratio (SNR) in the detection of low-frequency acoustic signals. This work introduces a capacitive hydrophone (CH) designed for highly sensitive detection of low-frequency underwater sound signals. Comprising a latex film/silver electrode and a structured hydrogel as the electrolyte layer, the CH is enclosed in a cylindrical casing. By strategically integrating a carbon nanotube (CNT) topology network within a pyramid microarray in the hydrogel, the sensor efficiently forms the electric double layer (EDL), enhancing sensitivity and precision. The CH showcases exceptional low-pressure sensitivity across a wide frequency spectrum (20 to 800 Hz), achieving a receiving sensitivity of up to -159.7 dB in the critical low-frequency band (20 to 125 Hz), surpassing the performance of the commercial hydrophone (RHC-14) by a substantial margin of 33.29 dB. Furthermore, the CH maintains a superior SNR, enabling the detection of sound waves as faint as 0.3 Pa. This study demonstrates the capabilities of the CH in detecting maritime vessels and underwater sounds, underscoring the potential of the CNT-enhanced EDL sensing mechanism for future low-frequency hydrophone design.

3.
CNS Neurosci Ther ; 30(8): e14917, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39123302

RESUMO

AIMS: To evaluate the efficacy, safety, and tolerability of adjunctive lacosamide therapy against focal seizures in young children (1 month - 4 years). METHODS: This non-randomized, open-label, and self-controlled real-world study included 105 children (1 month-4 years) with focal seizures treated with adjunctive lacosamide therapy at Children's Hospital of Chongqing Medical University. RESULTS: (1) The 50% response rates at 3, 6, 9, and 12 months of follow-up were 58.1%, 61.0%, 57.1%, and 56.2%, while the seizure-free rates were 27.6%, 34.3%, 32.4%, and 37.1%, respectively. The 50% response rate of the first addition of lacosamide for focal seizures was much higher than the second and later added treatment at 3 months (p = 0.038). After 1 year of follow-up, these children showed an improvement in neurodevelopmental levels (p < 0.05). (2) Lacosamide retention rate was 72.7% (64/88) after 1 year of follow-up. Lack of efficacy and serious adverse events were independent risk factors for the lacosamide retention rate. (3) During adjunctive lacosamide therapy, 13 (12.4%) patients reported adverse events and five (4.7%) patients withdrew due to adverse events, including vomiting drowsiness, ataxia (0.94%), neck itching with eczema (0.94%), irritability (1.88%), and gastrointestinal discomfort (0.94%). CONCLUSION: Adjunctive lacosamide therapy was effective, safe, and well-tolerated in young Chinese children with focal seizures in this study.


Assuntos
Anticonvulsivantes , Lacosamida , Convulsões , Humanos , Lacosamida/uso terapêutico , Lacosamida/administração & dosagem , Lacosamida/efeitos adversos , Masculino , Feminino , Anticonvulsivantes/uso terapêutico , Anticonvulsivantes/efeitos adversos , Anticonvulsivantes/administração & dosagem , Lactente , Pré-Escolar , Convulsões/tratamento farmacológico , Resultado do Tratamento , Seguimentos , Quimioterapia Combinada , Epilepsias Parciais/tratamento farmacológico
4.
Angew Chem Int Ed Engl ; : e202409145, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869085

RESUMO

Metal hexacyanoferrates (HCFs) are regarded as promising cathode materials for potassium-ion batteries (PIBs) on account of their low cost and high energy density. However, the difficult-to-remove [Fe(CN)6] vacancies and crystal water lead to structural instability and capacity deterioration as well as the stereotype of poor thermostability of conventional HCFs. Herein, we report (100) face-oriented potassium magnesium hexacyanoferrate (KMgHCF) nanoplates with low [Fe(CN)6] vacancies and high crystallinity, enabling thermostability up to 550 °C, high-temperature carbon coating and crystal water elimination. The as-obtained KMgHCF/C nanoplates exhibit superior potassium storage properties, including a large reversible capacity of 84.6 mAh g-1, a high voltage plateau of 3.87 V, excellent long-term cycling performance over 15000 cycles and high rate capability at 5 A g-1. The unprecedented cycling stability of KMgHCF/C is attributed to the synergistic effect of a highly reversible two-phase reaction, low [Fe(CN)6] vacancies and no crystal water, a specially exposed steady (100) surface, and a protective carbon coating. This work provides a new material selection and modification strategy for the practical application of HCFs in PIBs.

5.
World J Clin Cases ; 12(16): 2887-2893, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38899283

RESUMO

BACKGROUND: We present a case of an EWSR1/FUS::NFATC2 rearranged sarcoma in the left forearm and analyze its clinicopathological and molecular features. CASE SUMMARY: The patient is a 23-year-old woman. Microscopically, the tumor cells were medium-sized round cells arranged in small nests. The cytoplasm was clear, nuclei were relatively uniform, chromatin was dense, nucleoli were visible, and mitotic figures were rare. Immunohistochemically, the tumor cells were positive for Vimentin, INI-1, CD99, NKX2.2, CyclinD1, friend leukaemia virus integration 1, and NKX3.1. Next-generation sequencing revealed the presence of the EWSR1-NFATC2 fusion gene. EWSR1/FUS::NFATC2 rearranged sarcomas are rare and can easily be misdiagnosed. CONCLUSION: Clinical imaging, immunohistochemistry, and molecular pathology should be considered to confirm the diagnosis.

6.
Microbiol Res ; 285: 127769, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38797112

RESUMO

Carbapenem-resistant Klebsiella pneumoniae (CRKP) has emerged as a global threat due to its high mortality in clinical patients. However, the specific mechanisms underlying this increased mortality remain unclear. The objective of this study is to investigate how the development of a resistance phenotype contributes to the significantly higher mortality associated with this pathogen. To achieve this, a collection of isogeneic strains was generated. The clinical carbapenem-susceptible K. pneumoniae (CSKP) strain HKU3 served as the control isolate, while HKU3-KPC was created through conjugation with a blaKPC-2-bearing plasmid and served as clinical CRKP strain. Using a sepsis model, it was demonstrated that both HKU3 and HKU3-KPC exhibited similar levels of virulence. Flow cytometry, RNA-seq, and ELISA analysis were employed to assess immune cell response, M1 macrophage polarization, and cytokine storm induction, revealing that both strains elicited comparable types and levels of these immune responses. Subsequently, meropenem was utilized to treat K. pneumoniae infection, and it was found that meropenem effectively reduced bacterial load, inhibited M1 macrophage polarization, and suppressed serum cytokine production during HKU3 (CSKP) infection. However, these effects were not observed in the case of HKU3-KPC (CRKP) infection. These findings provide evidence that the high mortality associated with CRKP is attributed to its enhanced survival within the host during antibiotic treatment, resulting in a cytokine storm and subsequent host death. The development of an effective therapy for CRKP infections could significantly reduce the mortality caused by this pathogen.


Assuntos
Antibacterianos , Enterobacteriáceas Resistentes a Carbapenêmicos , Carbapenêmicos , Infecções por Klebsiella , Klebsiella pneumoniae , Meropeném , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/patogenicidade , Klebsiella pneumoniae/genética , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/mortalidade , Infecções por Klebsiella/tratamento farmacológico , Virulência , Antibacterianos/farmacologia , Meropeném/farmacologia , Carbapenêmicos/farmacologia , Animais , Camundongos , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Humanos , Macrófagos/microbiologia , Macrófagos/imunologia , beta-Lactamases/genética , beta-Lactamases/metabolismo , Sepse/microbiologia , Sepse/mortalidade , Sepse/tratamento farmacológico , Citocinas/metabolismo , Testes de Sensibilidade Microbiana , Proteínas de Bactérias/genética , Modelos Animais de Doenças , Carga Bacteriana
7.
Materials (Basel) ; 17(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38612088

RESUMO

The multifunctional development in the field of face masks and the growing demand for scalable manufacturing have become increasingly prominent. In this study, we utilized high-vacuum magnetron sputtering technology to deposit a 5 nm ultra-thin Ag-Cu film on non-woven fabric and fabricated ultra-thin Ag-Cu film face masks. The antibacterial rates against Escherichia coli and Staphylococcus aureus were 99.996% and 99.978%, respectively, while the antiviral activity against influenza A virus H1N1 was 99.02%. Furthermore, the mask's ability to monitor respiratory system diseases was achieved through color change (from brownish-yellow to grey-white). The low cost and scalability potential of ultra-thin silver-copper film masks offer new possibilities for practical applications of multifunctional masks.

8.
Front Oncol ; 14: 1320714, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38487727

RESUMO

Objective: We aimed to investigate the value of contrast-enhanced ultrasound (CEUS) in the preoperative prediction of the histological grades and molecular subtypes of breast cancer. Methods: A total of 183 patients with pathologically confirmed breast cancer were included. Contrast enhancement patterns and quantitative parameters were compared in different groups. The receiver operating characteristic (ROC) curve was used to analyze the efficacy of CEUS in the preoperative prediction of pathological characteristics, including histologic grade and molecular subtypes. Results: Heterogeneous enhancement, perfusion defects, and peripheral radial vessels were mostly observed in higher histologic grade (grade III) breast cancer. Heterogeneous enhancement and perfusion defect were the most effective indicators for grade III breast cancer, with the areas under the ROC curve of 0.768 and 0.756, respectively. There were significant differences in the enhancement intensity, post-enhanced margin, perfusion defects, and peripheral radial vessel among the different molecular subtypes of breast cancer (all P < 0.01). Perfusion defects and clear edge after enhancement were the best qualitative criteria for the diagnosis of HER-2 overexpressed and triple-negative breast cancers, and the corresponding areas under the ROC curves were 0.804 and 0.905, respectively. There were significant differences in PE, WiR, WiPI, and WiWoAUC between grade III vs grade I and II breast cancer (P < 0.05). PE, WiR, WiPI, and WiWoAUC had good efficiency in the diagnosis of high-histologic-grade breast cancer. PE had the highest diagnostic efficiency in Luminal A, while WiPI had the highest diagnostic efficiency in Luminal B subtype breast cancer, and the areas under the ROC curve were 0.825 and 0.838, respectively. WiWoAUC and WiR were the most accurate parameters for assessing triple-negative subtype breast cancers, and the areas under the curve were 0.932 and 0.922, respectively. Conclusion: Qualitative and quantitative perfusion analysis of contrast-enhanced ultrasound may be useful in the non-invasive prediction of the histological grade and molecular subtypes of breast cancers.

9.
J Psychol ; : 1-21, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546695

RESUMO

Previous studies have shown that anticipation induces more emotions than retrospection, known as temporal emotion asymmetry. However, the majority of previous studies have been confined to Western contexts. Eastern populations tend to emphasize the past more than their Western counterparts and may exhibit distinct forms of temporal emotion asymmetry. Therefore, we conducted an investigation involving Chinese adolescents. Our research encompassed two experiments, investigating Chinese adolescents' temporal emotion asymmetry from a self-perspective (Experiment 1; N = 124) and an other-perspective (Experiment 2; N = 162). Participants were prompted to retrospect and anticipate events that elicited pleasant or unpleasant feelings. The results revealed that, whether from a self-perspective or an other-perspective, retrospection of past positive events elicited greater pleasure than the anticipation of future positive events. However, concerning adverse events, under a self-perspective, anticipation induced more displeasure than retrospection (Experiment 1); under an other-perspective, retrospection induced more displeasure than anticipation (Experiment 2). Our findings provide some support for the construal level theory, fading affect bias, and mobilization-minimization hypothesis of event cognition. Based on these results, retrospection seems to be a potential means for regulating the emotions of Chinese adolescents.

10.
Microbiol Res ; 283: 127666, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38460283

RESUMO

The escalating prevalence of multidrug-resistant (MDR) bacteria pose a significant public health threat. Understanding the genomic features and deciphering the antibiotic resistance profiles of these pathogens is crucial for development of effective surveillance and treatment strategies. In this study, we employed the R10.4.1 nanopore sequencing technology, specifically through the use of the MinION platform, to analyze eight MDR bacterial strains originating from clinical, ecological and food sources. A single 72-hour sequencing run could yield approximately 12 million reads which covered a total of 34 gigabases (Gbp). The nanopore R10.4.1 data was processed using the Flye assembler, successfully assembling the genomes of eight bacterial strains and their 18 plasmids. Notably, the assemblies generated solely from R10.4.1 nanopore data closely matched those from next-generation sequencing data. Diverse antibiotic resistance patterns and specific resistance genes in the test strains were identified. Hospital strains that exhibited multidrug resistance were found to harbor various resistance genes that encode efflux pumps and extended-spectrum ß-lactamases. Environmental and food sources were found to display resistance profiles in a species-specific manner. The composition of structurally complex plasmids in the test strains could also be revealed by analysis of nanopore long reads, which also suggested evidence of horizontal transfer of plasmids between different bacterial species. These findings provide valuable insights into the genetic characteristics of MDR bacteria and demonstrating the practicality of nanopore sequencing technology for detecting of resistance elements in bacterial pathogens.


Assuntos
Sequenciamento por Nanoporos , Plasmídeos/genética , Genômica , Farmacorresistência Bacteriana Múltipla/genética , Genoma Bacteriano/genética , Bactérias/genética , Antibacterianos/farmacologia
11.
Sci Total Environ ; 926: 171924, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38522537

RESUMO

This study employs a comprehensive approach combining metagenomic analysis and bacterial isolation to elucidate the microbial composition, antibiotic resistance genes (ARGs), and virulence factors (VFGs) present in shrimps from market and supermarket. Metagenomic analysis of shrimps revealed a dominance of Proteobacteria and Bacteroidetes with Firmicutes notably enriched in some samples. On the other hand, the dominant bacteria isolated included Citrobacter portucalensis, Escherichia coli, Salmonella enterica, Vibrio species and Klebsiella pneumonaie. Metagenomic analysis unveiled a diverse spectrum of 23 main types and 380 subtypes of ARGs in shrimp samples including many clinical significant ARGs such as blaKPC, blaNDM, mcr, tet(X4) etc. Genomic analysis of isolated bacterial strains identified 14 ARG types with 109 subtype genes, which complemented the metagenomic data. Genomic analysis also allowed us to identify a rich amount of MDR plasmids, which provided further insights into the dissemination of resistance genes in different species of bacteria in the same samples. Examination of VFGs and mobile genetic elements (MGEs) in both metagenomic and bacterial genomes revealed a complex landscape of factors contributing to bacterial virulence and genetic mobility. Potential co-occurrence patterns of ARGs and VFGs within human pathogenic bacteria underlined the intricate interplay between antibiotic resistance and virulence. In conclusion, this integrated analysis for the first time provides a comprehensive view and sheds new light on the potential hazards associated with shrimp products in the markets. The findings underscore the necessity of ongoing surveillance and intervention strategies to mitigate risks posed by antibiotic-resistant bacteria in the food supply chain using the novel comprehensive approaches.


Assuntos
Decápodes , Genes Bacterianos , Animais , Humanos , Antibacterianos/farmacologia , Bactérias/genética , Plasmídeos , Resistência Microbiana a Medicamentos/genética , Crustáceos
12.
Sci Total Environ ; 921: 170903, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38354793

RESUMO

The Bacillus cereus group, as one of the important opportunistic foodborne pathogens, is considered a risk to public health due to foodborne diseases and an important cause of economic losses to food industries. This study aimed to gain essential information on the prevalence, phenotype, and genotype of B. cereus group strains isolated from various food products in China. A total of 890 strains of B. cereus group bacteria from 1181 food samples from 2020 to 2023 were identified using the standardized detection method. These strains were found to be prevalent in various food types, with the highest contamination rates observed in cereal flour (55.8 %) and wheat/rice noodles (45.7 %). The tested strains exhibited high resistance rates against penicillin (98.5 %) and ampicillin (98.9 %). Strains isolated from cereal flour had the highest rate of meropenem resistance (7.8 %), while strains from sausages were most resistant to vancomycin (16.8 %). A total of 234 out of the 891 B. cereus group strains were randomly selected for WGS analysis, 18.4 % of which displayed multidrug resistance. The species identification by WGS analysis revealed the presence of 10 distinct species within the B. cereus group, with B. cereus species being the most prevalent. The highest level of species diversity was observed in sausages. Notably, B. anthracis strains lacking the anthrax toxin genes were detected in flour-based food products and sausages. A total of 20 antibiotic resistance genes have been identified, with ß-lactam resistance genes (bla1, bla2, BcI, BcII, and blaTEM-116) being the most common. The B. tropicus strains exhibit the highest average number of virulence genes (23.4). The diarrheal virulence genes nheABC, hblACD, and cytK were found in numerous strains. Only 4 of the 234 (1.7 %) sequenced strains contain the ces gene cluster linked to emetic symptoms. These data offer valuable insights for public health policymakers on addressing foodborne B. cereus group infections and ensuring food safety.


Assuntos
Bacillus , Bacillus cereus/genética , Enterotoxinas/análise , Microbiologia de Alimentos , Prevalência , Genômica , Contaminação de Alimentos/análise
13.
Artigo em Inglês | MEDLINE | ID: mdl-38401086

RESUMO

Objective: The objective of this study was to integrate metabolomics and transcriptomics data to identify key diagnostic and prognostic markers for esophageal squamous cell carcinoma (ESCC). Plasma samples were collected from 85 ESCC patients at different stages and 50 healthy volunteers for non-targeted metabolomic analysis. Methods: Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was employed for non-targeted metabolomic analysis. Subsequently, we integrated the metabolomic data with transcriptomic data from the Gene Expression Omnibus (GEO) and prognosis data from The Cancer Genome Atlas Program (TCGA) to perform pathway analysis. Our focus was on pathways that involve both metabolites and upstream genes, as they often exhibit higher accuracy. Results: Through the integration of metabolomics and transcriptomics, we identified significant alterations in the platelet activation pathway in ESCC. This pathway involves the participation of both metabolites and genes, making it a more accurate reflection of pathological changes associated with the disease. Notably, metabolite arachidonic acid (AA) and chemokine receptor type 2(CXCR2) were significantly downregulated in ESCC, while genes collagen type I alpha 1(COL1A1), collagen type I alpha 2(COL1A2), collagen type III alpha 1(COL3A1), type 3 inositol 1,4,5-trisphosphate receptor (ITPR3), and insulin-like growth factor II mRNA binding protein 3(IGF2BP3) were significantly upregulated, indicating the presence of tumor-induced platelet activation in ESCC. Further analysis of prognosis data revealed that high expression of COL1A1, IGF2BP3, and ITPR3 was associated with a favorable prognosis for ESCC, while high CXCR2 expression was linked to an adverse prognosis. In addition, we combined COL1A1, ITPR3, IGF2BP3, CXCR2, and AA to form a diagnostic biomarker panel. The receiver operating characteristic curve (ROC) demonstrated excellent diagnostic capability (AUC=0.987). Conclusion: Our study underscores the significant role of platelet activation pathways and related genes in the diagnosis and prognosis of ESCC patients. These findings offer promising insights for improving the clinical management of ESCC.

14.
EBioMedicine ; 101: 104998, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340556

RESUMO

BACKGROUND: The epidemiological features of the Klebsiella pneumoniae causing bloodstream infections in Hong Kong and their potential threats to human health remained unknown. METHODS: K. pneumoniae strains collected from four hospitals in Hong Kong during the period of 2009-2018 were subjected to molecular typing, string test, antimicrobial susceptibility testing, whole genome sequencing and analysis. Clinical data of patients from whom these strains were isolated were analyzed retrospectively using univariate and multivariate logistic regression approaches. FINDINGS: The 240 Klebsiella spp. strains belonged to 123 different STs and 63 different capsule loci (KLs), with KL1 and KL2 being the major type. 86 out of 212 BSI-KP (40.6%) carried at least one of the virulence genes iuc, iro, rmpA or rmpA2. Virulence plasmid correlated well with the string test positive result, yet 8 strains without rmp genes were also hypermucoviscous, which was due to wzc mutation. The mortality rate of bloodstream infection patients was 43.0%. Univariant analysis showed that factors including renal replacement therapy (FDR adjusted p = 0.0007), mechanical ventilation (FDR adjusted p < 0.0001) and respiratory sepsis (FDR adjusted p < 0.0001) were found to pose the highest risk of death upon infection by Klebsiella spp. INTERPRETATION: This study revealed the high mortality rate and risk factors associated with bloodstream infections caused by K. pneumoniae in Hong Kong, which warrants immediate action to develop effective solution to tackle this problem. FUNDING: Theme Based Research Scheme (T11-104/22-R), Research Impact Fund (R5011-18 F) and Postdoctoral Fellowship (PDFS2223-1S09).


Assuntos
Infecções por Klebsiella , Sepse , Humanos , Hong Kong/epidemiologia , Klebsiella/genética , Epidemiologia Molecular , Estudos Retrospectivos , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/genética , Antibacterianos
15.
Nature ; 626(8000): 772-778, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38383625

RESUMO

High-capacity storage technologies are needed to meet our ever-growing data demands1,2. However, data centres based on major storage technologies such as semiconductor flash devices and hard disk drives have high energy burdens, high operation costs and short lifespans2,3. Optical data storage (ODS) presents a promising solution for cost-effective long-term archival data storage. Nonetheless, ODS has been limited by its low capacity and the challenge of increasing its areal density4,5. Here, to address these issues, we increase the capacity of ODS to the petabit level by extending the planar recording architecture to three dimensions with hundreds of layers, meanwhile breaking the optical diffraction limit barrier of the recorded spots. We develop an optical recording medium based on a photoresist film doped with aggregation-induced emission dye, which can be optically stimulated by femtosecond laser beams. This film is highly transparent and uniform, and the aggregation-induced emission phenomenon provides the storage mechanism. It can also be inhibited by another deactivating beam, resulting in a recording spot with a super-resolution scale. This technology makes it possible to achieve exabit-level storage by stacking nanoscale disks into arrays, which is essential in big data centres with limited space.

16.
Biomimetics (Basel) ; 9(2)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38392149

RESUMO

Stable communication technologies in complex waters are a prerequisite for underwater operations. Underwater acoustic communication is susceptible to multipath interference, while underwater optical communication is susceptible to environmental impact. The underwater electric field communication established based on the weak electric fish perception mechanism is not susceptible to environmental interference, and the communication is stable. It is a new type of underwater communication technology. To address issues like short communication distances and high bit error rates in existing underwater electric field communication systems, this study focuses on underwater electric field communication systems based on direct sequence spread spectrum (DSSS) and binary phase shift keying (BPSK) modulation techniques. To verify the feasibility of the established spread spectrum electric field communication system, static communication experiments were carried out in a swimming pool using the DSSS-based system. The experimental results show that in fresh water with a conductivity of 739 µS/cm, the system can achieve underwater current electric field communication within a 11.2 m range with 10-6 bit errors. This paper validates the feasibility of DSSS BPSK in short-range underwater communication, and compact communication devices are expected to be deployed on underwater robots for underwater operations.

17.
Front Cell Infect Microbiol ; 14: 1303099, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38299116

RESUMO

Introduction: The contamination of dental unit waterlines (DUWLs) poses a significant risk of cross-infection in dentistry. Although chemical disinfectants have been effective in reducing number of bacteria, they do have limitations. Methods: This study aimed to investigate the potential of chlorogenic acid, a natural substance with broadspectrum antibacterial properties, for treating DUWLs. Over a period of three months, we analyzed the microbial communities in 149 DUWLs samples collected from 5 dental units using high-throughput pyrophosphate sequencing. Results: The results revealed that chlorogenic acid treatment had a significant impact on the microbial community profile in the DUWLs, with the most significant changes occurring within the first 15 days and stabilization observed in the last 30 days. The predominant genera detected in the samples were Bacteroides, Lactobacillus, Streptococcus, Methylobacterium, and Phreatobacter. Additionally, the relative abundance of certain beneficial bacteria, such as Alloprevotella, Roseburia, and Blautia, increased, while the presence of opportunistic pathogens like Mycobacteria significantly decreased. The functional prediction analysis using the KEGG database indicated a decrease in the pathogenicity of the bacterial community in the DUWLs following chlorogenic acid treatment. Discussion: This study introduces a novel approach for the prevention and treatment of infections associated with dental care.


Assuntos
Ácido Clorogênico , Contaminação de Equipamentos , Ácido Clorogênico/farmacologia , Contagem de Colônia Microbiana , Contaminação de Equipamentos/prevenção & controle , Microbiologia da Água , Bactérias , Sequenciamento de Nucleotídeos em Larga Escala , Biofilmes
18.
Small ; 20(10): e2304407, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37880907

RESUMO

Cuproptosis is a novel form of regulated cell death which guarantees to increase the efficacy of existing anticancer treatments that employ traditional apoptotic therapeutics. However, reducing the amount of undesirable Cu ions released in normal tissue and maximizing Cu-induced cuproptosis therapeutic effects at tumor sites are the major challenges. In this study, exploiting the chemical properties of copper ionophores and the tumor microenvironment, a novel method is developed for controlling the valence of copper ions that cause photoinduced cuproptosis in tumor cells. CJS-Cu nanoparticles (NPs) can selectively induce cuproptosis after cascade reactions through H2 O2 -triggered Cu2+ release, photoirradiation-induced superoxide radical (∙O2 - ) generation, and reduction of Cu2+ to Cu+ by ∙O2 - . The generated reactive oxygen species can result in glutathione depletion and iron-sulfur cluster protein damage and further augmented cuproptosis. CJS-Cu NPs effectively suppressed tumor growth and downregulated the expression of metastasis-related proteins, contributing to the complete inhibition of lung metastasis. Ultimately, this study suggests novel avenues for the manipulation of cellular cuproptosis through photochemical reactions.


Assuntos
Neoplasias Pulmonares , Nanopartículas , Humanos , Cobre , Glutationa , Superóxidos , Apoptose , Microambiente Tumoral
19.
Small ; 20(14): e2309629, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37988699

RESUMO

LiMn1-yFeyPO4 (LMFP) is a significant and cost-effective cathode material for Li-ion batteries, with a higher working voltage than LiFePO4 (LFP) and improved safety features compared to layered oxide cathodes. However, its commercial application faces challenges due to a need for a synthesis process to overcome the low Li-ion diffusion kinetics and complex phase transitions. Herein, a solid-state synthesis process using LFP and nano LiMn0.7Fe0.3PO4 (MF73) is proposed. The larger LFP acts as a structural framework fused with nano-MF73, preserving the morphology and high performance of LFP. These results demonstrate that the solid-state reaction occurs quickly, even at a low sintering temperature of 500 °C, and completes at 700 °C. However, contrary to the expectations, the larger LFP particles disappeared and fused into the nano-MF73 particles, revealing that Fe ions diffuse more easily than Mn ions in the olivine framework. This discovery provides valuable insights into understanding ion diffusion in LMFP. Notably, the obtained LMFP can still deliver an initial capacity of 142.3 mAh g-1, and the phase separation during the electrochemical process is significantly suppressed, resulting in good cycling stability (91.1% capacity retention after 300 cycles). These findings offer a promising approach for synthesizing LMFP with improved performance and stability.

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