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1.
PLoS Comput Biol ; 20(3): e1011956, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38547311

RESUMO

SARS-CoV-2 transmission in indoor spaces, where most infection events occur, depends on the types and duration of human interactions, among others. Understanding how these human behaviours interface with virus characteristics to drive pathogen transmission and dictate the outcomes of non-pharmaceutical interventions is important for the informed and safe use of indoor spaces. To better understand these complex interactions, we developed the Pedestrian Dynamics-Virus Spread model (PeDViS), an individual-based model that combines pedestrian behaviour models with virus spread models incorporating direct and indirect transmission routes. We explored the relationships between virus exposure and the duration, distance, respiratory behaviour, and environment in which interactions between infected and uninfected individuals took place and compared this to benchmark 'at risk' interactions (1.5 metres for 15 minutes). When considering aerosol transmission, individuals adhering to distancing measures may be at risk due to the buildup of airborne virus in the environment when infected individuals spend prolonged time indoors. In our restaurant case, guests seated at tables near infected individuals were at limited risk of infection but could, particularly in poorly ventilated places, experience risks that surpass that of benchmark interactions. Combining interventions that target different transmission routes can aid in accumulating impact, for instance by combining ventilation with face masks. The impact of such combined interventions depends on the relative importance of transmission routes, which is hard to disentangle and highly context dependent. This uncertainty should be considered when assessing transmission risks upon different types of human interactions in indoor spaces. We illustrated the multi-dimensionality of indoor SARS-CoV-2 transmission that emerges from the interplay of human behaviour and the spread of respiratory viruses. A modelling strategy that incorporates this in risk assessments can help inform policy makers and citizens on the safe use of indoor spaces with varying inter-human interactions.


Assuntos
COVID-19 , Pedestres , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle , Aerossóis e Gotículas Respiratórios , Ventilação
2.
Small ; 20(4): e2306634, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37702138

RESUMO

Chemically inert organic networks exhibiting electrical conductivity comparable to metals can advance organic electronics, catalysis, and energy storage systems. Covalent-organic frameworks (COFs) have emerged as promising materials for those applications due to their high crystallinity, porosity, and tunable functionality. However, their low conductivity has limited their practical utilization. In this study, copper-coordinated-fluorinated-phthalocyanine and 2,3,6,7-tetrahydroxy-9,10-anthraquinone-based COF (CuPc-AQ-COF) films with ultrahigh conductivity are developed. The COF films exhibit an electrical conductivity of 1.53 × 103 S m-1 and a Hall mobility of 6.02 × 102 cm2 V-1 s-1 at 298 K, reaching the level of metals. The films are constructed by linking phthalocyanines and anthraquinones through vapor-assisted synthesis. The high conductivity properties of the films are attributed to the molecular design of the CuPc-AQ-COFs and the generation of high-quality crystals via the vapor-assisted method. Density functional theory analysis reveals that an efficient donor-acceptor system between the copper-coordinated phthalocyanines and anthraquinones significantly promotes charge transfer. Overall, the CuPc-AQ-COF films set new records of COF conductivity and mobility and represent a significant step forward in the development of COFs for electronic, catalytic, and electrochemical applications.

3.
Angew Chem Int Ed Engl ; 63(33): e202403917, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38818640

RESUMO

Although dearomative functionalizations enable the direct conversion of flat aromatics into precious three-dimensional architectures, the case for simple arenes remains largely underdeveloped owing to the high aromatic stabilization energy. We herein report a dearomative sequential addition of two nucleophiles to arene π-bonds through umpolung of chromium-arene complexes. This mode enables divergent dearomative carbonylation reactions of benzene derivatives by tolerating various nucleophiles in combination with alcohols or amines under CO-gas-free conditions, thus providing modular access to functionalized esters or amides. The tunable synthesis of 1,3- or 1,4-cyclohexadienes as well as the construction of carbon quaternary centers further highlight the versatility of this dearomatization. Diverse late-stage modifications and derivatizations towards synthetically challenging and bioactive molecules reveal the synthetic utility. A possible mechanism was proposed based on control experiments and intermediate tracking.

4.
Angew Chem Int Ed Engl ; 63(18): e202402202, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38375743

RESUMO

Poly(ethylene oxide) (PEO)-based electrolytes are often used for Li+ conduction as they can dissociate the Li salts efficiently. However, high entanglement of the chains and lack of pathways for rapid ion diffusion limit their applications in advanced batteries. Recent developments in ionic covalent organic frameworks (iCOFs) showed that their highly ordered structures provide efficient pathways for Li+ transport, solving the limitations of traditional PEO-based electrolytes. Here, we present imidazolate COFs, PI-TMEFB-COFs, having methoxyethoxy chains, synthesized by Debus-Radziszewski multicomponent reactions and their ionized form, Li+@PI-TMEFB-COFs, showing a high Li+ conductivity of 8.81 mS cm-1 and a transference number of 0.974. The mechanism for such excellent electrochemical properties is that methoxyethoxy chains dissociate LiClO4, making free Li+, then those Li+ are transported through the imidazolate COFs' pores. The synthesized Li+@PI-TMEFB-COFs formed a stable interface with Li metal. Thus, employing Li+@PI-TMEFB-COFs as the solid electrolyte to assemble LiFePO4 batteries showed an initial discharge capacity of 119.2 mAh g-1 at 0.5 C, and 82.0 % capacity and 99.9 % Coulombic efficiency were maintained after 400 cycles. These results show that iCOFs with ether chains synthesized via multicomponent reactions can create a new chapter for making solid electrolytes for advanced rechargeable batteries.

5.
Sensors (Basel) ; 23(24)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38139511

RESUMO

Data-driven approaches are helpful for quantitative justification and performance evaluation. The Netherlands has made notable strides in establishing a national protocol for bicycle traffic counting and collecting GPS cycling data through initiatives such as the Talking Bikes program. This article addresses the need for a generic framework to harness cycling data and extract relevant insights. Specifically, it focuses on the application of estimating average bicycle delays at signalized intersections, as this is an essential variable in assessing the performance of the transportation system. This study evaluates machine learning (ML)-based approaches using GPS cycling data. The dataset provides comprehensive yet incomplete information regarding one million bicycle rides annually across The Netherlands. These ML models, including random forest, k-nearest neighbor, support vector regression, extreme gradient boosting, and neural networks, are developed to estimate bicycle delays. The study demonstrates the feasibility of estimating bicycle delays using sparse GPS cycling data combined with publicly accessible information, such as weather information and intersection complexity, leveraging the burden of understanding local traffic conditions. It emphasizes the potential of data-driven approaches to inform traffic management, bicycle policy, and infrastructure development.

6.
Angew Chem Int Ed Engl ; 62(38): e202307690, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37524652

RESUMO

The lack of anion exchange membranes (AEMs) that possess both high hydroxide conductivity and stable mechanical and chemical properties poses a major challenge to the development of high-performance fuel cells. Improving one side of the balance between conductivity and stability usually means sacrificing the other. Herein, we used facile, high-yield chemical reactions to design and synthesize a piperidinium polymer with a polyethylene backbone for AEM fuel cell applications. To improve the performance, we introduced ionic crosslinking into high-cationic-ratio AEMs to suppress high water uptake and swelling while further improving the hydroxide conductivity. Remarkably, PEP80-20PS achieved a hydroxide conductivity of 354.3 mS cm-1 at 80 °C while remaining mechanically stable. Compared with the base polymer PEP80, the water uptake of PEP80-20PS decreased by 69 % from 813 % to 350 %, and the swelling decreased substantially by 85 % from 350.0 % to 50.2 % at 80 °C. PEP80-20PS also showed excellent alkaline stability, 84.7 % remained after 35 days of treatment with an aqueous KOH solution. The chemical design in this study represents a significant advancement toward the development of simultaneously highly stable and conductive AEMs for fuel cell applications.

7.
Anal Bioanal Chem ; 414(16): 4707-4716, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35562571

RESUMO

Although numerous fluorescence sensors for Cu2+ have been presented, a long-wavelength sensor in aqueous media has rarely been reported as expected due to practical application requirements. In this work, a novel AIE molecule (DHBB) containing two biphenylacrylonitrile units bridged by dibenzylidenehydrazine was prepared. It possessed the merits of long-wavelength emission, good emission in aqueous media, and multiple functional groups for binding Cu2+. It exhibited good sensing selectivity for Cu2+ among all kinds of tested metal ions. The detection limit was as low as 1.08 × 10-7 M. The sensing mechanism was clarified as 1:1 stoichiometric ratio based on the binding cooperation of O and N functional groups of DHBB. The selective sensing ability for Cu2+ remained stable at pH = 5-9 and was influenced little by other metal ions. The Cu2+ sensing ability of DHBB was applied in real samples with 96% recovery rate. The bio-imaging experiment of living cells suggested that DHBB possessed not only good bio-imaging performance but also sensing ability for Cu2+ in living environments. This work suggested the good application prospect of DHBB to sense Cu2+ in real samples and living environment.


Assuntos
Corantes Fluorescentes , Água , Cobre , Corantes Fluorescentes/química , Íons , Metais , Espectrometria de Fluorescência/métodos
8.
Sensors (Basel) ; 22(13)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35808434

RESUMO

Various lengths of time window have been used in feature extraction for electroencephalogram (EEG) signal processing in previous studies. However, the effect of time window length on feature extraction for the downstream tasks such as emotion recognition has not been well examined. To this end, we investigate the effect of different time window (TW) lengths on human emotion recognition to find the optimal TW length for extracting electroencephalogram (EEG) emotion signals. Both power spectral density (PSD) features and differential entropy (DE) features are used to evaluate the effectiveness of different TW lengths based on the SJTU emotion EEG dataset (SEED). Different lengths of TW are then processed with an EEG feature-processing approach, namely experiment-level batch normalization (ELBN). The processed features are used to perform emotion recognition tasks in the six classifiers, the results of which are then compared with the results without ELBN. The recognition accuracies indicate that a 2-s TW length has the best performance on emotion recognition and is the most suitable to be used in EEG feature extraction for emotion recognition. The deployment of ELBN in the 2-s TW can further improve the emotion recognition performances by 21.63% and 5.04% when using an SVM based on PSD and DE features, respectively. These results provide a solid reference for the selection of TW length in analyzing EEG signals for applications in intelligent systems.


Assuntos
Eletroencefalografia , Processamento de Sinais Assistido por Computador , Eletroencefalografia/métodos , Emoções , Humanos , Reconhecimento Psicológico
9.
J Insect Sci ; 20(1)2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32061083

RESUMO

Plant tannins, polyphenolic plant secondary metabolites are involved in important chemical defense processes in plants. In this study, tannic acid was used as the standard of plant tannins to determine the effects on nutritional indices and activities of glutathione S-transferases (GSTs), cytochrome P450 monooxygenase (CYP450), carboxylesterase (CarE), and acetylcholinesterase (AChE) in fourth-instar larvae of Hyphantria cunea (Drury) by feeding on an artificial diet containing tannic acid under different treatments. We found that tannic acid significantly affected the digestive capacity and food utilization rate of H. cunea larvae. A tannic acid concentration of less than 2.0% promoted feeding and the utilization of undesirable food by H. cunea larvae, while inhibitory effects were observed at high concentrations (>2.5%). Tannic acid had a significant effect on the activity of detoxification enzymes and AChE in H. cunea larvae in concentration-dependent and time-dependent manners (P < 0.05). These results provide new insights into the potential mechanisms underlying detoxification in H. cunea larvae against tannic acid in host plants.


Assuntos
Mariposas/efeitos dos fármacos , Taninos/farmacologia , Acetilcolinesterase/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Carboxilesterase/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Glutationa Transferase/metabolismo , Inativação Metabólica , Larva/efeitos dos fármacos , Larva/enzimologia , Mariposas/enzimologia , Mariposas/crescimento & desenvolvimento
10.
J Med Internet Res ; 17(6): e143, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26068214

RESUMO

BACKGROUND: Patients have been increasingly seeking and using Internet health information to become more active in managing their own health in a partnership with their physicians. This trend has both positive and negative effects on the interactions between patients and their physicians. Therefore, it is important to understand the impact that the increasing use of Internet health information has on the patient-physician relationship and patients' compliance with their treatment regimens. OBJECTIVE: This study examines the impact of patients' use of Internet health information on various elements that characterize the interactions between a patient and her/his physician through a theoretical model based on principal-agent theory and the information asymmetry perspective. METHODS: A survey-based study consisting of 225 participants was used to validate a model through various statistical techniques. A full assessment of the measurement model and structural model was completed in addition to relevant post hoc analyses. RESULTS: This research revealed that both patient-physician concordance and perceived information asymmetry have significant effects on patient compliance, with patient-physician concordance exhibiting a considerably stronger relationship. Additionally, both physician quality and Internet health information quality have significant effects on patient-physician concordance, with physician quality exhibiting a much stronger relationship. Finally, only physician quality was found to have a significant impact on perceived information asymmetry, whereas Internet health information quality had no impact on perceived information asymmetry. CONCLUSIONS: Overall, this study found that physicians can relax regarding their fears concerning patient use of Internet health information because physician quality has the greatest impact on patients and their physician coming to an agreement on their medical situation and recommended treatment regimen as well as patient's compliance with their physician's advice when compared to the impact that Internet health information quality has on these same variables. The findings also indicate that agreement between the patient and physician on the medical situation and treatment is much more important to compliance than the perceived information gap between the patient and physician (ie, the physician having a higher level of information in comparison to the patient). In addition, the level of agreement between a patient and their physician regarding the medical situation is more reliant on the perceived quality of their physician than on the perceived quality of Internet health information used. This research found that only the perceived quality of the physician has a significant relationship with the perceived information gap between the patient and their physician and the quality of the Internet health information has no relationship with this perceived information gap.


Assuntos
Informação de Saúde ao Consumidor , Internet , Cooperação do Paciente , Relações Médico-Paciente , Adulto , Idoso , Idoso de 80 Anos ou mais , Competência Clínica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Percepção , Médicos , Inquéritos e Questionários , Adulto Jovem
11.
Adv Mater ; : e2407761, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39155807

RESUMO

Rechargeable secondary batteries, widely used in modern technology, are essential for mobile and consumer electronic devices and energy storage applications. Lithium (Li)-ion batteries are currently the most popular choice due to their decent energy density. However, the increasing demand for higher energy density has led to the development of Li metal batteries (LMBs). Despite their potential, the commonly used liquid electrolyte-based LMBs present serious safety concerns, such as dendrite growth and the risk of fire and explosion. To address these issues, using solid-state electrolytes in batteries has emerged as a promising solution. In this Perspective, recent advancements are discussed in ionic covalent organic framework (ICOFs)-based solid-state electrolytes, identify current challenges in the field, and propose future research directions. Highly crystalline ion conductors with polymeric versatility show promise as the next-generation solid-state electrolytes. Specifically, the use of anionic or cationic COFs is examined for Li-based batteries, highlight the high interfacial resistance caused by the intrinsic brittleness of crystalline ICOFs as the main limitation, and presents innovative ideas for developing all- and quasi-solid-state batteries using ICOF-based solid-state electrolytes. With these considerations and further developments, the potential for ICOFs is optimistic about enabling the realization of high-energy-density all-solid-state LMBs.

12.
Front Med (Lausanne) ; 11: 1420264, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39188874

RESUMO

Purpose: To comprehensively compare the long-term outcome of the combined topography guided photorefractive keratectomy (TG-PRK) with accelerated corneal cross-linking (ACXL) and ACXL alone in eyes with progressive keratoconus. The analysis focused on the changes in the detailed corneal aberrometric values. Methods: This single-center, prospective cohort study included 28 patients (30 eyes) of the TG-PRK plus ACXL group and 14 patients (15 eyes) of the ACXL alone group. The mean duration of the follow-up was 44 ± 10.18 months (ranged from 31 to 65 months). The preoperative data and the postoperative measurement data at the last follow-up visit, including demographic data, uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction, corneal topography, pachymetry, aberrometry and densitometry were analyzed. Results: The CDVA significantly improved in the TG-PRK plus ACXL group at the last follow-up visit (p = 0.006), while no significant improvement was found in the ACXL alone group (p = 0.432). The maximal keratometry of the anterior corneal surface (Kmax) of both groups significantly decreased at the last follow-up visit (p < 0.05). Compared with the ACXL alone group, the Kmax of the TG-PRK plus ACXL group showed a greater decline (p = 0.008). The total corneal aberrations, the corneal lower-order aberrations (LOAs), the corneal higher order aberrations (HOAs), the vertical coma and the spherical aberration (SA) at the 4.0 mm and 6.0 mm zone of the TG-PRK plus ACXL group significantly decreased at the last follow-up visit (all p < 0.05). The declines of the total corneal aberrations, the corneal LOAs, the corneal HOAs and the vertical coma at the 4.0 mm and 6.0 mm zone of the TG-PRK plus ACXL group were significantly higher than those in the ACXL alone group (p < 0.001). Conclusion: Compared with ACXL alone, combined TG-PRK with ACXL procedure had a significantly higher reduction in the corneal HOAs and better CDVA, while providing a similar long-term stability and safety. For progressive keratoconus patients with adequate corneal thickness, the combined procedure might be a recommended treatment option.

13.
ACS Appl Mater Interfaces ; 16(34): 44957-44966, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39137352

RESUMO

Ideal solid electrolytes for lithium (Li) metal batteries should conduct Li+ rapidly with low activation energy, exhibit a high Li+ transference number, form a stable interface with the Li anode, and be electrochemically stable. However, the lack of solid electrolytes that meet all of these criteria has remained a considerable bottleneck in the advancement of lithium metal batteries. In this study, we present a design strategy combining all of those requirements in a balanced manner to realize quasi-solid-state electrolyte-enabled Li metal batteries (LMBs). We prepared Li+-coordinated triptycene-based ionic porous organic polymers (Li+@iPOPs). The Li+@iPOPs with imidazolates and phenoxides exhibited a high conductivity of 4.38 mS cm-1 at room temperature, a low activation energy of 0.627 eV, a high Li+ transference number of 0.95, a stable electrochemical window of up to 4.4 V, excellent compatibility with Li metal electrodes, and high stability during Li deposition/stripping cycles. The high performance is attributed to charge delocalization in the backbone, mimicking the concept of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), which facilitates the diffusion of coordinated Li+ through the porous space of the triptycene-based iPOPs. In addition, Li metal batteries assembled using Li+@Trp-Im-O-POPs as quasi-solid-state electrolytes and a LiFePO4 cathode showed an initial capacity of 114 mAh g-1 and 86.7% retention up to 200 cycles.

14.
Adv Mater ; 35(16): e2210952, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36608278

RESUMO

Macrocycles with well-defined cavities and the ability to undergo supramolecular interactions are classical materials that have played an essential role in materials science. However, one of the most substantial barriers limiting the utilization of macrocycles is their aggregation, which blocks the active regions. Among many attempted strategies to prevent such aggregation, installing macrocycles into covalent organic frameworks (COFs), which are porous and stable reticular networks, has emerged as an ideal solution. The resulting macrocycle-based COFs (M-COFs) preserve the macrocycles' unique activities, enabling applications in various fields such as single-atom catalysis, adsorption/separation, optoelectronics, phototherapy, and structural design of forming single-layered or mechanically interlocked COFs. The resulting properties are unmatchable by any combination of macrocycles with other substrates, opening a new chapter in advanced materials. This review focuses on the latest progress in the concepts, synthesis, properties, and applications of M-COFs, and presents an in-depth outlook on the challenges and opportunities in this emerging field.

15.
Biotechnol Genet Eng Rev ; : 1-21, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37130192

RESUMO

This study was conducted to illustrate the origin of these PE-related ncRNAs in maternal circulation and their underlying transport methods into target cells. We selected 10 women with severe pre-eclampsia (PE group) and 10 healthy participants who served as controls (NC group). Exosomes were isolated from their sera and their origin was determined by a specific marker, placental alkaline phosphatase (PLAP). We compared the ncrna associated with PE in exosomes and whole serum to observe the exchange of serum exosomes with trophoblast cells. The results showed that PLAP was enriched in the isolated exosomes. Seven PE-associated ncRNAs, including lnc-SNHG5, miR-26a-5p, miR-221-3p, miR-30a-3p, miR-18a, miR-152 and miR-155, were analyzed in placenta-derived exosomes and whole serum from both groups. miR-26a-5p, miR-152 and miR-155 were upregulated in the PE group compared with the NC group. 152 and miR-155 were upregulated. 152 and miR-155 were upregulated, while miR-18a and miR-221-3p were downregulated (P<0.05). ncRNAs were altered in serum and placenta-derived serum exosomes in a consistent trend. Fluorescence microscopy results showed that the nuclei were counterstained in HTR-8 cells exposed to PKH26-labeled exosomes. PE-associated ncRNAs can enter the maternal circulation through secretion and encapsulation into placenta-derived exosomes and participate in the development and progression of PE by targeting trophoblast cells. differential expression of ncRNAs in exosomes has the potential to be used as predictors for targeted therapy, providing new ideas and perspectives for improving maternal and infant outcomes.

16.
Food Sci Nutr ; 11(8): 4812-4828, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37576054

RESUMO

Both edible fungal polysaccharides (Auricularia and Tremellan) and Crataegus flavonoids promote the balance of dyslipidemia, which have a positive biological regulating effect on intestinal flora. In this study, the extraction of water-soluble polysaccharides from Auricularia and Tremellan was investigated and optimized firstly. Polysaccharides and flavonoids were then combined to study the effects on the mediating role of abnormal blood lipid concentration and intestinal flora in vivo. The rats were divided into 10 groups, the NC (normal control), HM (model), PCI (Simvastatin control), PCII (Fenofibrate control), AAP (Auricularia auricular Polysaccharide), TFP (Tremella fuciformis Polysaccharide), HF (Crataegus Flavonoid), LDC (Low-dose combination), MDC (Medium dose combination), and HDC (High-dose combination), used to explore the impact of polysaccharides and flavonoids complex on state of blood lipid, liver, and intestinal flora of dyslipidemia rats. The results showed that the combination of polysaccharides and flavonoids could significantly decrease the levels of triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL-C), and increase the level of high-density lipoprotein cholesterol (HDL-C). It also significantly decreased the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and improved liver morphology. What is more, the HDC favorably alters the intestinal microflora balance, promotes intestinal integrity and mobility, and inhibits the growth of harmful bacteria such as Escherichia coli/Shigella and Clostridium compared with HM group. In brief, the combination of polysaccharides and flavonoids had a synergistic effect on the remission of dyslipidemia, and promoted health by improving lipid metabolism, protecting liver tissue, and regulating the intestinal flora in hyperlipidemia rats.

17.
Nanoscale ; 15(25): 10558-10566, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37309844

RESUMO

Recent advances in adsorbents have improved the removal of mercury ions from wastewater. Metal-organic frameworks (MOFs) have been increasingly used as adsorbents due to their high adsorption capacity and ability to adsorb various heavy metal ions. UiO-66 (Zr) MOFs are mainly used because they are highly stable in aqueous solutions. However, most functionalized UiO-66 materials are unable to achieve a high adsorption capacity because of the undesired reactions that occur during post-functionalization. Herein, we report a facile post-functionalization method to synthesize a MOF adsorbent with fully active amide- and thiol-functionalized chelating groups, termed UiO-66-A.T. UiO-66-A.T. was synthesized via a two-step reaction by crosslinking with a monomer containing a disulfide moiety, followed by disulfide cleavage to activate the thiol groups. UiO-66-A.T. removed Hg2+ from water with a maximum adsorption capacity of 691 mg g-1 and a rate constant of 0.28 g mg-1 min-1 at pH 1. In a mixed solution containing 10 different heavy metal ions, UiO-66-A.T. has a Hg2+ selectivity of 99.4%, which is the highest reported to date. These results demonstrate the effectiveness of our design strategy for synthesizing purely defined MOFs to achieve the best Hg2+ removal performance to date among post-functionalized UiO-66-type MOF adsorbents.


Assuntos
Mercúrio , Metais Pesados , Poluentes Químicos da Água , Cinética , Água , Adsorção
18.
World J Clin Cases ; 11(14): 3167-3175, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37274032

RESUMO

BACKGROUND: The incidence of lumbar tuberculosis is high worldwide, and effective treatment is a continuing problem. AIM: To study the safety and efficacy of the multitrack and multianchor point screw technique combined with the contralateral Wiltse approach for lesion debridement to treat lumbar tuberculosis. METHODS: The C-reactive protein (CRP) level, erythrocyte sedimentation rate (ESR), visual analogue scale (VAS) score, oswestry disability index (ODI) and American Spinal Injury Association (ASIA) grade were recorded and analysed pre- and postoperatively. RESULTS: The CRP level and ESR returned to normal, and the VAS score and ODI were decreased at 3 mo postoperatively, with significant differences compared with the preoperative values (P < 0.01). Neurological dysfunction was relieved, and the ASIA grade increased, with no adverse events. CONCLUSION: The multitrack, multianchor point screw fixation technique combined with the contralateral Wiltse approach for debridement is an effective and safe method for the treatment of lumbar tuberculosis.

19.
Biomed Res Int ; 2022: 8804925, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36093396

RESUMO

Background: Alzheimer's disease, a neurodegenerative memory disease, primarily results from the formation of amyloid plaques (Aß) that gradually inhibit neuron communications. The entire mechanism of Aß production remains unclear to date, and it is of particular interest among scientists to find out the exact mechanism that leads to amyloid precursor protein (APP) cleavage through the amyloidogenic pathway so that effective treatments can be developed. Method: 2 sets of experiments with the use of human H4-N cell lines are proposed to fully investigate the validity of the hypothesis. All of the experiments would involve immunoblotting of Aß using an anti-Aß antibody, and the results would be analyzed with the assistance of an image analyzer. A significant amount of Aß would be expected to be present in the cytoplasm of cells with herpes simplex virus (HSV-1) applied, as APP endocytosis would be induced by HSV-1, which leads to higher Aß levels inside the cell. Results: In this paper, a new hypothesis is presented on how HSV-1 infection initiates APP endocytosis and causes an increase in APP cleavage and Aß production inside the cells. It is also hypothesized that increased Aß peptides exit the cell via exocytosis, therefore, leading to the development of Alzheimer's disease. The findings will support the hypothesis if intracellular Aß concentration is significantly higher after the introduction of dHSV-1 and subsequently if extracellular Aß concentration becomes higher without TeNT exocytosis inhibition. Conclusion: The results of this study would provide valuable insights into the mechanisms underlying Alzheimer's disease and open new scopes of research for its potential treatments. Further studies on virus infection and the development of memory diseases should be conducted to investigate possible correlations.


Assuntos
Doença de Alzheimer , Herpes Simples , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides , Humanos , Neurônios/metabolismo , Placa Amiloide
20.
STAR Protoc ; 3(3): 101477, 2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-35769928

RESUMO

Although a trace amount of Fe3+ is essential for human physiological function, excessive amounts are lethal. Here, we present a protocol for removing Fe3+ from water through highly crystalline and stable thiol-functionalized Zr metal-organic frameworks (Zr-MOFs). We provide details of the MOFs synthesis and post-functionalization procedures, and include key performance data of the Zr-MOFs for removing Fe3+, which were collected from the inductively coupled plasma-optical emission spectrometer (ICP-OES) and inductively coupled plasma mass spectrometer (ICP-MS). For complete details on the use and execution of this protocol, please refer to Yuan et al. (2022).


Assuntos
Estruturas Metalorgânicas , Humanos , Espectrometria de Massas , Estruturas Metalorgânicas/química , Água/química
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