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1.
Analyst ; 149(8): 2420-2427, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38488061

RESUMEN

Antimicrobial resistance has become a major global health threat due to the misuse and overuse of antibiotics. Rapid, affordable, and high-efficiency antimicrobial susceptibility testing (AST) is among the effective means to solve this problem. Herein, we developed a capillary-based centrifugal indicator (CBCI) equipped with an in situ culture of pathogenic bacteria for fast AST. The bacterial incubation and growth were performed by macro-incubation, which seamlessly integrated the capillary indicator. Through simple centrifugation, all the bacterial cells were confined at the nanoliter-level capillary column. The packed capillary column height could linearly reflect the bacterial count, and the minimum inhibitory concentration (MIC) was determined based on the difference in the column height between the drug-added groups and the control group. The AST results could easily be determined by the naked eye or smartphone imaging. Thus, the CBCI realized the combination of macro-bacterial incubation and early micro assessment, which accelerated the phenotypic AST without complex microscopic counting or fluorescent labelling. The whole operation process was simple and easy to use. AST results could be determined for E. coli ATCC strains within 3.5 h, and the output results for clinical samples were consistent with the hospital reports. We expect this AST platform to become a useful tool in limiting antimicrobial resistance, especially in remote/resource-limited areas or in underdeveloped countries.


Asunto(s)
Antibacterianos , Escherichia coli , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana , Bacterias
2.
Environ Res ; 252(Pt 3): 119043, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38692422

RESUMEN

It is of great significance to establish an effective method for removing Cr(VI) from wastewater. Herein, Fe-doped g-C3N4 (namely Fe-g-C3N4-2) was synthesized and then employed as photocatalyst to conduct the test of Cr(VI) reduction. Notably, the embedding of Fe ion in g-C3N4 can offer the Fe2+/Fe3+ redox couples, so reducing the interfacial resistance of charge transfer and suppressing the recombination of photogenerated electrons and holes. The impurity energy levels will form in g-C3N4 after the introduction of Fe ion, thereby boosting the light absorption capacity of catalyst. Thus, Fe-g-C3N4-2 showed good performance in photocatalytic Cr(VI) reduction, and the reduction efficiency of Cr(VI) can reach 39.9% within 40 min. Different with many previous studies, current work unexpectedly found that the addition of p-benzoquinone (BQ) can promote the Cr(VI) reduction, and the reduction efficiency of Cr(VI) over Fe-g-C3N4-2 was as high as 93.2% in the presence of BQ (1.5 mM). Further analyses showed that BQ can be reduced to hydroquinone (HQ) by photogenerated electrons, and UV light can also directly induce BQ to generate HQ by using H2O as the hydrogen donor. The HQ with reducing ability can accelerate the Cr(VI) reduction. In short, current work shared some novel insights into photocatalytic Cr(VI) reduction in the presence of BQ. Future research should consider possible reactions between photogenerated electrons and BQ. For the UV-induced photocatalysis, the suitability of BQ as the scavenger of O2•‒ must be given carefully consideration.


Asunto(s)
Benzoquinonas , Cromo , Hierro , Oxidación-Reducción , Benzoquinonas/química , Cromo/química , Catálisis , Hierro/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/efectos de la radiación , Procesos Fotoquímicos , Compuestos de Nitrógeno/química , Compuestos de Nitrógeno/efectos de la radiación , Grafito
3.
Anal Chem ; 95(5): 3028-3036, 2023 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-36688612

RESUMEN

We developed a bent-capillary-centrifugal-driven (BCCD) monodisperse droplet generator, which could achieve a perfect combination of driving and segmentation for the dispersed phase only using a rotating bent capillary immersed in the continuous phase (mineral oil). The sample could flow continuously to the bent-capillary outlet to form the droplet precursors, which were segmented into homogeneous droplets in the continuous phase. Through the investigation of influence factors on droplet size and stability, we found that the droplet size could be conveniently controlled by the rotational speed of the bent capillary. The droplet volumes could be adjusted with the range from 34 pL to 1 µL, and the coefficient variations (CVs) were less than 3%. Meanwhile, the BCCD droplet generator could realize the controllable droplet output with a high-efficiency sample utilization of 99.75 ± 1.15%, which offered a significant advantage in reducing the waste of precious samples in the droplet generation process. We validated this system with a digital loop-mediated isothermal amplification (dLAMP) assay for the absolute quantification of Mycobacterium tuberculosis complex nucleic acids. The results demonstrated that the BCCD droplet generator was easy to build, was of low cost, and was convenient to operate, as well as avoided sample loss and cross-contamination by coupling with a 96-well plate. Overall, the present platform, as a simple chip-free droplet generator, will provide an especially valuable droplet generation solution for biochemical applications based on droplets.


Asunto(s)
Técnicas de Amplificación de Ácido Nucleico , Ácidos Nucleicos , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas de Diagnóstico Molecular , Aceite Mineral
4.
Nano Lett ; 22(4): 1595-1603, 2022 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-35133850

RESUMEN

Optical beam steerers have been widely employed for information acquisitions. Numerous beam steering schemes have been developed, and each of them can satisfy practical requirements for certain scenarios. However, there is still a lack of a comprehensive approach that is able to balance all of the critical technical parameters for wide range of applications. Here, a semisolid micromechanical beam steering system based on micrometa-lens arrays (MMLAs) is demonstrated. It is operated by manipulating the probe beam over two sets of decentered MMLAs potentially driven by high-speed piezo-electric motors. Small f-numbers, well-corrected aberration, and easy lateral reproduction of micrometa-lenses optimize the overall technical parameters. As a proof-of-concept, we implement such a device exhibiting diffraction-limited resolution within a large field of view of 30° × 30°. A three-dimensional depth sensing is also performed to demonstrate its potential in light detection and ranging applications.


Asunto(s)
Lentes , Diseño de Equipo , Análisis de Falla de Equipo
5.
J Org Chem ; 86(2): 1540-1548, 2021 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-33353304

RESUMEN

Photocarboxylation of alkyne with carbon dioxide represents a highly attractive strategy to prepare functionalized alkenes with high efficiency and atomic economy. However, the reaction mechanism, especially the sequence of elementary steps (leading to different reaction pathways), reaction modes of the H-transfer step and carboxylation step, spin and charge states of the cobalt catalyst, etc., is still an open question. Herein, density functional theory calculations are carried out to probe the mechanism of the Ir/Co-catalyzed photocarboxylation of alkynes. The overall catalytic cycle mainly consists of four steps: reductive-quenching of the Ir catalyst, hydrogen transfer (rate-determining step), outer sphere carboxylation, and the final catalyst regeneration step. Importantly, the cobalt catalyst can facilitate the H-transfer by an uncommon hydride coupled electron transfer (HCET) process. The pivotal electron delivery effect of the Co center enables a facile H-transfer to the α-C(alkyne) of the aryl group, resulting in the high regioselectivity for ß-carboxylation.

6.
BMC Med Inform Decis Mak ; 19(Suppl 2): 63, 2019 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-30961584

RESUMEN

BACKGROUND: Extracting relations between bio-entities from biomedical literature is often a challenging task and also an essential step towards biomedical knowledge expansion. The BioCreative community has organized a shared task to evaluate the robustness of the causal relationship extraction algorithms in Biological Expression Language (BEL) from biomedical literature. METHOD: We first map the sentence-level BEL statements in the BC-V training corpus to the corresponding text segments, thus generating hierarchically tagged training instances. A hierarchical sequence labeling model was afterwards induced from these training instances and applied to the test sentences in order to construct the BEL statements. RESULTS: The experimental results on extracting BEL statements from BioCreative V Track 4 test corpus show that our method achieves promising performance with an overall F-measure of 31.6%. Furthermore, it has the potential to be enhanced by adopting more advanced machine learning approaches. CONCLUSION: We propose a framework for hierarchical relation extraction using hierarchical sequence labeling on the instance-level training corpus derived from the original sentence-level corpus via word alignment. Its main advantage is that we can make full use of the original training corpus to induce the sequence labelers and then apply them to the test corpus.


Asunto(s)
Investigación Biomédica , Minería de Datos , Lenguaje , Procesamiento de Lenguaje Natural , Algoritmos , Recolección de Datos , Humanos , Aprendizaje Automático
7.
Opt Lett ; 43(10): 2414-2417, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-29762606

RESUMEN

In this Letter, we demonstrated an intensity-modulated directional torsion sensor based on an in-line Mach-Zehnder interferometer in single-mode fiber. A non-circular symmetric perturbation is created to excite non-circular symmetric cladding mode and then interference with the core mode at the second perturbation. An initial rotation angle is designed between two perturbations for the purpose of discriminating the torsion direction. Both experimental and theoretical results enforce that the spectral peak/dip turns to be the dip/peak when the fiber is twisted from the counter-clockwise to the clockwise direction. Benefiting from the reversal between peak and dip, an intensity-modulated directional torsion sensor is realized in the range from -50 rad/m to 50 rad/m with a sensitivity of 45.3%/(rad/cm).

8.
World J Microbiol Biotechnol ; 34(9): 131, 2018 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-30105649

RESUMEN

A new yeast strain which was capable of degrading various azo dyes under high-salt conditions was identified in this study. The results showed that the yeast named S4 was identified as Cyberlindnera samutprakarnensis through 26S rDNA sequence analysis and could decolorize more than 97% of Acid Red B (ARB) within 18 h under the optimal conditions. The acute toxicity of ARB sharply decreased after degradation. NADH-DCIP reductase and lignin peroxidase were determined as the key reductase and oxidase of the yeast S4, respectively. Furthermore, it was proposed that ARB was degraded by strain S4 successively through reduction of azo bonds, hydroxylation, deamination, desulfonation and finally to the TCA cycle.


Asunto(s)
Adaptación Fisiológica , Compuestos Azo/metabolismo , Biodegradación Ambiental , Saccharomycetales/metabolismo , Aliivibrio fischeri/efectos de los fármacos , Compuestos Azo/química , Compuestos Azo/toxicidad , Colorantes/química , Colorantes/metabolismo , Colorantes/toxicidad , ADN Ribosómico/genética , Inactivación Metabólica , Naftalenosulfonatos/química , Naftalenosulfonatos/metabolismo , Peroxidasas/metabolismo , Filogenia , Quinona Reductasas/metabolismo , Saccharomycetales/enzimología , Saccharomycetales/genética , Saccharomycetales/aislamiento & purificación , Análisis de Secuencia , Cloruro de Sodio/metabolismo , Aguas Residuales , Purificación del Agua
9.
Front Public Health ; 12: 1455718, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39267630

RESUMEN

Background: The factors influencing vaccination decision-making for newly developed vaccines may be similar to and different from those for established vaccines. Understanding these underlying differences and similarities is crucial for designing targeted measures to promote new vaccines against potential novel viruses. Objective: This study aims to compare public vaccination decisions for newly developed and established vaccines and to identify the differences and similarities in the influencing factors. Method: A discrete choice experiment (DCE) was conducted on 1,509 representatives of the general population in China to collect data on preferences for the coronavirus disease 2019 (COVID-19) and influenza vaccines, representing the newly developed and established vaccines, respectively. The latent class logit model was used to identify latent classes within the sample, allowing for an analysis of the factors distinctly influencing choices for both types of vaccines. Result: Participants valued similar attributes for both vaccines. However, concerns about sequelae were more significant for the newly developed vaccine, while effectiveness was prioritized for the established vaccine. Class membership analysis revealed these differences and similarities were significantly correlated with age, health, yearly household income, acquaintances' vaccination status, and risk perception. Conclusion: The study highlights the need for tailored communication strategies and targeted vaccination interventions. For the newly developed vaccines, addressing concerns about side effects is more crucial. For long-standing vaccines, emphasizing their effectiveness can enhance uptake more significantly. Engaging healthcare providers and community influencers is essential for both vaccines to increase public confidence and vaccination rates. Clear communication and community engagement are critical strategies for addressing public concerns and misinformation, particularly during periods of heightened concern.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Toma de Decisiones , Vacunas contra la Influenza , Vacunación , Humanos , China , Adulto , Masculino , Femenino , Persona de Mediana Edad , Vacunas contra la Influenza/administración & dosificación , Vacunas contra la COVID-19/administración & dosificación , Vacunación/estadística & datos numéricos , Vacunación/psicología , COVID-19/prevención & control , Adulto Joven , Modelos Logísticos , SARS-CoV-2 , Gripe Humana/prevención & control , Encuestas y Cuestionarios , Anciano , Adolescente , Análisis de Clases Latentes , Conducta de Elección
10.
J Colloid Interface Sci ; 678(Pt B): 885-901, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39270389

RESUMEN

Designing efficient sulfide photocatalysts for the simultaneous split water into H2 and O2 continue to be an arduous challenge. Herein, a Zn-vacancy mediated S-scheme MnCdS/ZnS-VZn heterojunction derived from MnCdS/MOF-5 via in-situ vulcanization of MOF-5 in a new-fashioned sacrificial reagent of Na2S/NaH2PO2 was fabricated. The presence of Zn vacancy (VZn) was certified by TEM, XPS, EPR and PL results, which result in a new defect level in the band structure of ZnS. The S-scheme charge transfer path was established between MnCdS and ZnS-VZn by VZn vacancies, and the photocorrosion is depressed efficiently and a dramatic rise occurs on photocatalytic performance. The strong electron coupling effect of S-scheme heterojunction mechanism was confirmed via in-situ XPS, SPV, work function, and radicals test by EPR. The band gap and density of state about ZnS-VZn and MnCdS are also calculated by the DFT. In HER semi-reaction, the strongest photocatalytic hydrogen generation rate of 20 % MnCdS/ZnS-VZn is 394.4 µmol/h with a splendid apparent quantum efficiency of 16.43 % at 420 nm, and the turnover number (TON) is 98.6. The hydrogen production rate of 20 % MnCdS/ZnS-VZn is drastically advanced by 123.25 times in contrast to the unadorned ZnS-VZn. And superior photostability is also obtained. Prominently, the high-efficiency and steady photocatalytic overall water splitting rates of 5.7µmol/h (H2) and 3.0µmol/h (O2) were achieved over 20 % MnCdS/ZnS-VZn with 1 %wt Pt and 5 %wt Co3O4 nanorod as cocatalysts, and the photocatalytic stability was excellent. This research supplies neoteric insights for designing of highly efficient VZn-mediated S-scheme sulfide photocatalysts to achieve pure water overall splitting with superior photocatalytic activity.

11.
ACS Omega ; 9(7): 8464-8470, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38405496

RESUMEN

Long noncoding RNA (lncRNA) has been shown to participate in adipogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). In this study, we aimed to investigate the role of lncRNA-LOC646762 in adipogenic differentiation of BMSCs. Transcriptome sequencing revealed a positive correlation between LOC646762 transcription and expression of adipogenic marker genes in adipogenic differentiation. Moreover, LOC646762 overexpression did not negatively impact the cell proliferation of BMSCs. Besides, LOC646762 plays a crucial role in adipogenic differentiation, as evidenced by its positive correlation with adipogenic marker gene expression. Its possible interaction with its proposed target C/EBPß suggests its involvement in essential pathways governing adipogenesis. Collectively, our study outcomes provide valuable insights into the molecular mechanisms underlying the adipogenic differentiation of BMSCs and lay a strong foundation for further research in regenerative medicine.

12.
IEEE Trans Med Imaging ; PP2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38900618

RESUMEN

Several deep learning-based methods have been proposed to extract vulnerable plaques of a single class from intravascular optical coherence tomography (OCT) images. However, further research is limited by the lack of publicly available large-scale intravascular OCT datasets with multi-class vulnerable plaque annotations. Additionally, multi-class vulnerable plaque segmentation is extremely challenging due to the irregular distribution of plaques, their unique geometric shapes, and fuzzy boundaries. Existing methods have not adequately addressed the geometric features and spatial prior information of vulnerable plaques. To address these issues, we collected a dataset containing 70 pullback data and developed a multi-class vulnerable plaque segmentation model, called PolarFormer, that incorporates the prior knowledge of vulnerable plaques in spatial distribution. The key module of our proposed model is Polar Attention, which models the spatial relationship of vulnerable plaques in the radial direction. Extensive experiments conducted on the new dataset demonstrate that our proposed method outperforms other baseline methods. Code and data can be accessed via this link: https://github.com/sunjingyi0415/IVOCT-segementaion.

13.
Soc Sci Med ; 360: 117321, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39270573

RESUMEN

This study explores the impact of serious illnesses, such as cancer, on patients' time preferences in medical decision-making. Specifically, we assess how patients value extending their lifespan by one year under varying survival prognoses through three experimental studies. The findings reveal that patients exhibit a higher Subjective Discount Rates (SDR) in their medical decisions after a serious illness diagnosis. Notably, this difference in individual health also affects the time preferences of their family members. Additionally, the subjective contextual setting of the illness can also increase an individual's SDR levels. The research highlights a tendency for patients and families facing a potential short life expectancy to focus more on immediate concerns, leading to potentially shortsighted and irrational medical choices. This behavior often results in regret during the end-of-life stage. These insights are vital for healthcare professionals in optimizing treatment plans and for policymakers in understanding patient behaviors more comprehensively. The study emphasizes the need for considering psychological and behavioral changes in patients grappling with severe health challenges.

14.
Int J Biol Macromol ; 277(Pt 3): 134370, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39094864

RESUMEN

Ulcerative Colitis (UC) is a chronic inflammatory disease of the intestinal tract with unknown definitive etiology. Polysaccharides are among the most important active components of Abelmoschi Corolla, exhibitings various pharmacological activities such as antioxidation and immunomodulation. However, no studies have yet reported the application of Abelmoschi Corolla Polysaccharides (ACP) in treating UC. This study aims to highlight the therapeutic efficacy of ACP in UC and reveal the underlying mechanism. The potential therapeutic effect is initially verified using a dextran sodium sulfate (DSS)-induced colitis model. 16S rRNA sequencing is performed using feces samples and untargeted metabolomics using serum samples to further reveal that ACP reprograms the dysbiosis triggered by UC progression, increases the abundance of Bacteroides spp., Blautia spp., and Parabacteroides spp. at the genus level and enriches the serum concentration of 7-ketodeoxycholic acid (7-KDA). Furthermore, using the FXR-/- mouse model, it is revealed that Farnesoid X Receptor (FXR) is a key target for ACP and the metabolite 7-KDA to block STAT3 phosphorylation by repairing the intestinal barrier to attenuate UC. Taken together, this work highlights the therapeutic potential of ACP against UC, mainly exerting its effects via modulating gut microbiota and regulating the FXR/STAT3 signaling pathway.


Asunto(s)
Abelmoschus , Microbioma Gastrointestinal , Polisacáridos , Receptores Citoplasmáticos y Nucleares , Factor de Transcripción STAT3 , Transducción de Señal , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Factor de Transcripción STAT3/metabolismo , Polisacáridos/farmacología , Polisacáridos/química , Transducción de Señal/efectos de los fármacos , Ratones , Receptores Citoplasmáticos y Nucleares/metabolismo , Abelmoschus/química , Sulfato de Dextran , Modelos Animales de Enfermedad , Masculino , Colitis/tratamiento farmacológico , Colitis/metabolismo , Colitis/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/metabolismo , Colitis Ulcerosa/microbiología , Ratones Endogámicos C57BL
15.
Anal Chim Acta ; 1314: 342781, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38876519

RESUMEN

BACKGROUND: Okadaic acid (OA), as a diarrhetic shellfish poisoning, can increase the risk of acute carcinogenic or teratogenic effects for the ingestion of OA contaminated shellfish. At present, much effort has been made to graft immunoassay onto a paper substrate to make paper-based sensors for rapid and simple detection of shellfish toxin. However, the complicated washing steps and low protein fixation efficiency on the paper substrate need to be further addressed. RESULTS: A novel paper-tip immunosensor for detecting OA was developed combined with smartphone and naked eye readout. The trapezoid paper tip was consisted of quantitative and qualitative detection zones. To improve the OA antigen immobilization efficiency on the paper substrate, graphene oxide (GO)-assisted protein immobilization method was introduced. Meanwhile, Au nanoparticles composite probe combined with the lateral flow washing was developed to simplify the washing step. The OA antigen-immobilized zone, as the detection zone Ⅰ, was used for quantitative assay by smartphone imaging. The paper-tip front, as the detection zone Ⅱ, which could qualitatively differentiate OA pollution level within 45 min using the naked eye. The competitive immunoassay on the paper tip exhibited a wide linear range for detecting OA (0.02-50 ng∙mL-1) with low detection limit of 0.02 ng∙mL-1. The recovery of OA in spiked shellfish samples was in the range of 90.3 %-113.%. SIGNIFICANCE: These results demonstrated that the proposed paper-tip immunosensor could provide a simple, low-cost and high-sensitivity test for OA detection without the need for additional large-scale equipment or expertise. We anticipate that this paper-tip immunosensor will be a flexible and versatile tool for on-site detecting the pollution of marine products.


Asunto(s)
Técnicas Biosensibles , Oro , Grafito , Ácido Ocadaico , Papel , Teléfono Inteligente , Grafito/química , Ácido Ocadaico/análisis , Inmunoensayo/métodos , Oro/química , Nanopartículas del Metal/química , Proteínas Inmovilizadas/química , Límite de Detección , Animales , Anticuerpos Inmovilizados/inmunología , Anticuerpos Inmovilizados/química
16.
Int J Oncol ; 64(3)2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38214378

RESUMEN

Long­stranded non­coding RNAs (lncRNAs) are RNAs that consist of >200 nucleotides. The majority of lncRNAs do not encode proteins but have been revealed to mediate a variety of important physiological functions. Antisense­lncRNAs (AS­lncRNAs) are transcribed from the opposite strand of a protein or non­protein coding gene as part of the antisense strand of the coding gene. AS­lncRNAs can serve an important role in the tumorigenesis, prognosis, metastasis and drug resistance of a number of malignancies. This has been reported to be exerted through various mechanisms, such as endogenous competition, promoter interactions, direct interactions with mRNAs, acting as 'scaffolds' to regulate mRNA half­life, interactions with 5­untranslated regions and regulation of sense mRNAs. AS­lncRNAs have been found to either inhibit or promote tumor aggressiveness by regulating cell proliferation, energy metabolism, inflammation, inflammatory­carcinoma transformation, invasion, migration and angiogenesis. In addition, accumulating evidence has documented that AS­lncRNAs can regulate tumor therapy resistance. Therefore, targeting aberrantly expressed AS­lncRNAs for cancer treatment may prove to be a promising approach to reverse therapy resistance. In the present review, research advances on the role of AS­lncRNAs in tumor occurrence and development were summarized, with the aim of providing novel ideas for further research in this field.


Asunto(s)
Neoplasias , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , Neoplasias/genética , Regulación Neoplásica de la Expresión Génica
17.
Front Chem ; 11: 1103792, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36817175

RESUMEN

The separation of brines with high Mg/Li mass ratios is a huge challenge. To provide a theoretical basis for the design of separation materials, the hydration of Li+ and Mg2+ in confinement using carbon nanotubes (CNTs) as the 1-D nanopore model was investigated using a multiscale theoretical approach. According to the analysis of the first coordination layer of cations, we determined that the coordination shells of two cations exist inside CNTs, while the second coordination shells of the cations are unstable. Moreover, the results of the structure analysis indicate that the hydration layer of Li+ is not complete in CNTs with diameters of 0.73, 0.87, and 1.00 nm. However, this does not occur in the 0.60 nm CNT, which is explained by the formation of contact ion pairs (CIP) between Li+ and Cl- that go through a unstable solvent-shared ion pair [Li(H2O)4]+, and this research was further extended by 400 ns in the 0.60 nm CNT to address the aforementioned results. However, the hydration layer of Mg2+ is complete and not sensitive to the diameter of CNTs using molecular dynamics simulation and an ab initio molecular dynamics (AIMD) method. Furthermore, the results of the orientation distribution of Li+ and Mg2+ indicate that the water molecules around Mg2+ are more ordered than water molecules around Li+ in the CNTs and are more analogous to the bulk solution. We conclude that it is energetically unfavorable to confine Li+ inside the 0.60-nm diameter CNT, while it is favorable for confining Li+ inside the other four CNTs and Mg2+ in all CNTs, which is driven by the strong electrostatic interaction between cations and Cl-. In addition, the interaction between cations and water molecules in the five CNTs was also analyzed from the non-covalent interaction (NCI) perspective by AIMD.

18.
J Pain Res ; 16: 809-819, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36925621

RESUMEN

Purpose: To evaluate transcutaneous electrical acupoint stimulation (TEAS) on the perioperative rehabilitation of patients undergoing laparoscopic myomectomy. Patients and Methods: One hundred and five women undergoing laparoscopic hysteromyomectomy were randomly divided into TEAS group (Group T) and control group (Group C). Propofol and remifentanil were used to stabilize patient blood pressure and keep BIS between 40 and 60. Group T patients received TEAS at LI4/PC6 30 minutes before the operation and lasting until the end of anesthesia, followed by TEAS at ST36/SP6 for 30 minutes in PACU. All required indicators were recorded. Results: Group T patients required lower dosages of remifentanil and vasoactive drugs, and had a reduced incidence of propofol injection pain and intraoperative hypotension compared to Group C. Group T also had a lower maximum NRS score in PACU, lower NRS scores at 1 hour and 24 hours, and a lower incidence of vomiting within 24 hours. In addition, the QoR-40 score for Group T at 24 hours after operation was higher in terms of physical comfort, emotional state, pain and total score. Conclusion: TEAS can reduce the amount of anesthetic, maintain hemodynamic stability, reduce postoperative pain, reduce postoperative vomiting, enhance the recovery of gastrointestinal function, increase the quality of postoperative recovery and thus accelerate overall patient recovery.

19.
Chemosphere ; 344: 140348, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37793551

RESUMEN

It has been previously reported that pre-magnetization could enhance the efficacy of zero-valent iron (ZVI) in removing contaminants. However, little is known about the effects and persistence of different magnetization methods on pre-magnetized ZVI (Pre-ZVI) when used in advanced oxidation processes (AOPs). Gaining a comprehensive understanding of the durability of various pre-magnetization methods in enhancing the removal efficiency of different pollutants will significantly impact the widespread utilization of Pre-ZVI in practical engineering. Herein, we investigated the efficiency of dry and wet Pre-ZVI-activated peroxymonosulfate (PMS) in eliminating oxytetracycline (OTC) and evaluated the durability of Pre-ZVI. Additionally, we examined several factors that influence the degradation process's efficiency. Our results found that the reaction constant k values corresponding to the dry Pre-ZVI/PMS system at the pH values of 3, 7, and 9 varied from approximately 0.0384, 0.0331, and 0.0349 (day 1) to roughly 0.0297, 0.0278, and 0.0314 (day 30), respectively. Meanwhile, the wet Pre-ZVI/PMS system exhibited k values ranging from approximately 0.0392, 0.0349, and 0.0374 (day 1) to roughly 0.0380, 0.0291, and 0.0322 (day 30), respectively. Moreover, we proposed four OTC degradation pathways using LC-MS/MS and density functional theory calculations. The toxicity of the degradation products was assessed using the ecological structure activity relationship and the toxicity estimation software tool. Overall, this study provides insights into the application of Pre-ZVI/PMS that can be selectively used to eliminate tetracycline antibiotics from water.


Asunto(s)
Oxitetraciclina , Contaminantes Químicos del Agua , Hierro/química , Cromatografía Liquida , Contaminantes Químicos del Agua/química , Espectrometría de Masas en Tándem
20.
Anal Chim Acta ; 1280: 341872, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37858570

RESUMEN

A simple and flexible fabrication method of paper SERS substrate was developed by nanoparticles (NPs) droplet self-assembly at the paper tip with a temperature gradient (PTTG). We turned the drawback of the coffee ring effect into an effective way of preparing paper SERS substrate. When the NPs droplets were continuously dripped onto the PTTG, NPs were densely and uniformly distributed at the paper-tip front based on the combination of gravity and the coffee ring effect, which could achieve 91.2-fold improvement of SERS performance compared to a flat filter paper. Meanwhile, the analytes could also be enriched at the paper-tip front, which could achieve 9.3-fold signal enhancement compared to the paper-tip tail. Thus, the PTTG realized an excellent signal amplification for SERS detection. The paper-tip SERS substrate combined with a portable Raman spectrometer yielded an excellent analytical enhancement factor of 1.15 × 105 with the detection limit of 10 nM Rhodamine 6G (R6G). The whole fabrication procedure was completed within 2 h, and the paper-tip substrate showed a satisfactory substrate-to-substrate reproducibility with a relative standard deviation (RSD) of 5.13% (n = 10). It was successfully applied for quantitatively detecting real samples of oxytetracycline and malachite green with recoveries of 83.84-105.25% (n = 3). Meanwhile, we further evaluated the SERS performance of the PTTG using a laboratory-based Raman spectrometer, and it could realize the detection as low as 10 pM R6G. The proposed paper-tip substrate would offer a promising potential application for the on-site SERS analysis of food safety and environmental health.

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