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1.
Int Immunol ; 35(5): 243-253, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-36591893

RESUMO

Immunogenicity can be evaluated by detecting antibodies (Abs) induced by an antigen. Presently deployed assays, however, do not consider the negative impacts of Ab poly-specificity, which is well established at the monoclonal antibody level. Here, we studied antibody poly-specificity at the serum level (i.e. nonspecific Ab-probe interactions, NSIs), and ended up establishing a new platform for viral peptide immunogenicity evaluation. We first selected three peptides of high, medium and low immunogenicity, using a 'vaccine serum response rate'-based approach (i.e. the gold standard). These three peptides (Pi) in the bovine serum albumin-Pi form were used to immunize chickens, resulting in longitudinal serum samples for screening with a non-cognate peptide library. The signal intensity of Ab-peptide specific binding and 'NSI count' was used to evaluate the viral peptides' immunogenicity. Only the NSI count agreed with the gold standard. The NSI count also provides more informative data on antibody production than the aggregated signal intensity by whole-protein-based indirect enzyme-linked immunosorbent assay.


Assuntos
Especificidade de Anticorpos , Imunoglobulinas , Peptídeos , Proteínas Virais , Biblioteca de Peptídeos , Imunoglobulinas/sangue , Animais , Galinhas , Vírus da Doença de Newcastle/imunologia , Peptídeos/imunologia , Ensaio de Imunoadsorção Enzimática , Formação de Anticorpos , Proteínas Virais/imunologia
2.
Macromol Rapid Commun ; : e2400064, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594967

RESUMO

Polyethylene (PE), a highly prevalent non-biodegradable polymer in the field of plastics, presents a waste management issue. To alleviate this issue, bio-based PE (bio-PE), derived from renewable resources like corn and sugarcane, offers an environmentally friendly alternative. This review discusses various production methods of bio-PE, including fermentation, gasification, and catalytic conversion of biomass. Interestingly, the bio-PE production volumes and market are expanding due to the growing environmental concerns and regulatory pressures. Additionally, the production of PE and bio-PE biocomposites using agricultural waste as filler materials, highlights the growing demand for sustainable alternatives to conventional plastics. According to previous studies, addition of ≈50% defibrillated corn and abaca fibers into bio-PE matrix and a compatibilizer, results in the highest Young's modulus of 4.61 and 5.81 GPa, respectively. These biocomposites have potential applications in automotive, building construction, and furniture industries. Moreover, the advancement made in abiotic and biotic degradation of PE and PE biocomposites is elucidated to address their environmental impacts. Finally, the paper concludes with insights into the opportunities, challenges, and future perspectives in the sustainable production and utilization of PE and bio-PE biocomposites. In summary, production of PE and bio-PE biocomposites can contribute to a cleaner and sustainable future.

3.
Sensors (Basel) ; 23(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36772692

RESUMO

Text summarization is an information compression technology to extract important information from long text, which has become a challenging research direction in the field of natural language processing. At present, the text summary model based on deep learning has shown good results, but how to more effectively model the relationship between words, more accurately extract feature information and eliminate redundant information is still a problem of concern. This paper proposes a graph neural network model GA-GNN based on gated attention, which effectively improves the accuracy and readability of text summarization. First, the words are encoded using a concatenated sentence encoder to generate a deeper vector containing local and global semantic information. Secondly, the ability to extract key information features is improved by using gated attention units to eliminate local irrelevant information. Finally, the loss function is optimized from the three aspects of contrastive learning, confidence calculation of important sentences, and graph feature extraction to improve the robustness of the model. Experimental validation was conducted on a CNN/Daily Mail dataset and MR dataset, and the results showed that the model in this paper outperformed existing methods.

4.
Nano Lett ; 22(3): 942-947, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35089050

RESUMO

The oriented attachment (OA) of 0D semiconductor nanocrystals into 1D and 2D nanostructures with unique properties is useful for the fabrication of quantum confined nanomaterials that are otherwise difficult to produce by direct synthesis. Given that the OA of 1D nanocrystals such as nanorods generally produces linear chains, rod-couple structures, or clustered columns, linking them in a facet-specific manner to produce 2D structures is challenging. Here, we report that 1D Cu2-xS nanorods undergo etching on exposure to hexylphosphonic acid under mild heating, which results in an increased curvature and a reduction in surface ligands at those sites. This causes the nanorods to fuse via their basal tip facets into chains and then cojoin through diametrically opposed side facets, resulting in atomically coupled, 2D raftlike structures. The stepwise OA of 1D nanocrystals into 2D nanostructures illustrated here expands the range of nanoarchitectures that can be produced via solution-processed methods.

5.
Anal Chem ; 94(4): 1974-1982, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35044162

RESUMO

Antibody-antigen (Ab-Ag) interactions are canonically described by a model that exclusively accommodates noninteraction (0) or reproducible interaction (RI) states, yet this model is inadequate to explain often-encountered nonreproducible signals. Here, by monitoring diverse experimental systems using a peptide-protein hybrid microarray, we observed that Ab-probe interactions comprise a substantial proportion of nonreproducible antibody-based results. This enabled our discovery and capacity to reliably identify nonreproducible Ab-probe interactions (NRIs), as well as our development of a powerful explanatory model ("0-NRI-RI-Hook four-state model") that is mAb concentration-dependent, regardless of specificity, which ultimately shows that both nonspecific interactions and NRIs are not predictable yet certain to happen. Our discoveries challenge the centrality of Ab-Ag interaction specificity data in serology and immunology.


Assuntos
Anticorpos , Antígenos , Especificidade de Anticorpos , Peptídeos
6.
Int J Mol Sci ; 23(18)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36142286

RESUMO

We previously found that cordycepin inhibits the growth and metastasis formation of MDA-MB-231 cells through the Hedgehog pathway but has not validated this in vivo. In this study, we confirmed cordycepin's anti-triple-negative breast cancer (TNBC) effect in nude mice and documented its mechanism. We found that cordycepin reduced the volume and weight of MDA-MB-231 xenografts and affected the expression of proliferation-, apoptosis-, epithelial-mesenchymal transition-, and matrix metalloproteinase-related proteins without side effects. RNA sequencing screening, pathway enrichment, and the protein network interaction analysis revealed enriched pathways and targets mainly concentrated on the Hedgehog pathway and its core components of SHH and GLI2. This indicates that the Hedgehog pathway plays a central role in the cordycepin-mediated regulation of growth and metastasis formation in TNBC. The database analysis of the Hedgehog pathway markers (SHH, PTCH1, SMO, GLI1, and GLI2) revealed that the Hedgehog pathway is activated in breast cancer tissues, and its high expression is not conducive to a patient's survival. Finally, we verified that cordycepin effectively inhibited the Hedgehog pathway in TNBC through Western blotting and immunohistochemistry. This study found that cordycepin could regulate the growth and metastasis formation of TNBC through the Hedgehog pathway in vivo, which provides new insights for targeting and treating breast cancer.


Assuntos
Proteínas Hedgehog , Neoplasias de Mama Triplo Negativas , Animais , Linhagem Celular Tumoral , Proliferação de Células , Desoxiadenosinas , Proteínas Hedgehog/metabolismo , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Neoplasias de Mama Triplo Negativas/metabolismo , Proteína GLI1 em Dedos de Zinco/genética
7.
Health Qual Life Outcomes ; 18(1): 154, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32456638

RESUMO

BACKGROUND: Most hypertensive clients are elderly, whose health-related quality of life (HRQL) may be associated with self-perceptions of aging (older individuals' beliefs about their own aging). Meanwhile, culture and health disparities between rural and urban populations are substantial. Whether there are differences in self-perceptions of aging, HRQL, and their association among elderly hypertensive clients in urban and rural areas remains unknown. The objective of this study was to investigate and compare self-perceptions of aging and HRQL and their association among urban and rural older Chinese hypertensive clients. METHODS: A cross-sectional investigation was conducted in 15 urban community clinics and 22 village clinics from Suzhou, China. Older hypertensive adults were invited to complete a self-administered questionnaire addressing socio-demographic and clinical information, HRQL and self-perceptions of aging. RESULTS: There were 492 urban participants and 537 rural participants included in the analyses. The physical (40.0 ± 12.1 vs. 30.9 ± 8.9, P <  0.001) and mental (51.5 ± 8.3 vs. 46.0 ± 7.8, P <  0.001) HRQL scores of urban participants were all higher than those of rural ones. Urban participants' scores on dimensions of "timeline cyclical", "consequences negative", and "control negative" of self-perceptions of aging questionnaire (APQ) were lower than those of rural participants (P <  0.001, respectively), while the scores on dimensions of "consequences positive" and "control positive" were higher (P <  0.001, respectively). Adjusted multivariate linear regression showed that participants who had worse self-perceptions of aging had poorer HRQL. Some APQ dimensions associated with urban or rural hypertensive elders' HRQL were different. CONCLUSIONS: Older hypertensive clients in rural areas have poorer self-perceptions of aging and HRQL than those in urban areas. Health care professionals should pay more attention to HRQL and self-perceptions of aging of older hypertensive clients in rural areas.


Assuntos
Envelhecimento/psicologia , Hipertensão/psicologia , Qualidade de Vida , Autoimagem , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , População Rural/estatística & dados numéricos , Inquéritos e Questionários , População Urbana/estatística & dados numéricos
8.
Psychogeriatrics ; 19(4): 391-398, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30786326

RESUMO

BACKGROUND: In China, quality of life (QOL) of the elderly with hypertension was lower than that of normal elderly and lower self-perceptions of aging (SPA) in the elderly with chronic diseases have been shown. Previous studies showed that SPA played a key role in QOL of the elderly. We hypothesised that SPA were associated with QOL in Chinese elderly with hypertension, with more negative SPA predicting lower QOL. METHODS: A cross-sectional survey was conducted in one comprehensive hospital, 15 urban community clinics and 22 rural village clinics in Suzhou. In total, 1029 Chinese elderly with hypertension completed the self-administered questionnaires, including socio-demographic and clinical characteristics, aging perceptions questionnaire which contained seven dimensions and Medical Outcomes Study 36-item Short Form Health Survey evaluating QOL which included physical component summary (PCS) and mental component summary (MCS). RESULTS: Correlation analysis between SPA and QOL showed that most dimensions of SPA were correlated with PCS and MCS, except for Emotional Representations not correlated with MCS. The results of multivariate logistic regression analysis showed: the dimensions Timeline Chronic (B = -2.651, P < 0.001), Consequences Negative (B = -2.155, P < 0.001) and Emotional Representations (B = -2.672, P < 0.001) had a negative association with PCS, while Timeline Cyclical (B = 1.401, P = 0.023), Consequences Positive (B = 1.200, P = 0.011) and Control Positive (B = 1.425, P = 0.004) had a positive association with PCS; the dimensions Timeline Cyclical (B = -1.734, P < 0.001) and Consequences Negative (B = -1.646, P < 0.001) had a negative association with MCS, while Timeline Chronic (B = 1.313, P < 0.001), Consequences Positive (B = 0.962, P = 0.012), Control Positive (B = 2.453, P < 0.001) and Control Negative (B = 1.860, P < 0.001) had a positive association with MCS. CONCLUSIONS: Our results suggest that negative SPA tended to be associated with lower QOL in Chinese elderly with hypertension. Some measures to improve unhealthy negative SPA should be delivered to improve QOL in Chinese elderly with hypertension.


Assuntos
Envelhecimento/psicologia , Hipertensão/psicologia , Qualidade de Vida/psicologia , Autoimagem , Idoso , Idoso de 80 Anos ou mais , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Nano Lett ; 16(10): 6431-6436, 2016 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-27607441

RESUMO

Nonclassical growth mechanisms such as self-assembly and oriented attachment are effective ways to build complex nanostructures from simpler ones. In the latter case, the nanoparticle components are electronically coupled; however, control over the attachment between nanoparticles is highly challenging and generally requires a delicate balance between dipole-, ligand-, and solvent-based interactions. To this end, we perform incomplete cation exchange with Ag+ (Cu+) on CdSe-seeded CdS nanorods and tetrapods to exclusively convert their tips into small Ag2S (Cu2S) domains. Selective removal of the ligands from these inorganic domains results in spontaneous, site-specific bridging of the nanoparticles. Using this method, we demonstrate the fabrication of polymer-like linear and branched nanoparticles with enhanced electrical properties, as well as the stoichiometric formation of nanoparticle homo- and heterodimers and tetramers. We show that linked structures can then be completely cation exchanged with Pb2+ to generate PbSe/PbS-based nanostructured photodetector media with enhanced properties.

10.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 40(9): 1039-42, 2015 Sep.
Artigo em Zh | MEDLINE | ID: mdl-26408627

RESUMO

From July 2013 to February 2015, 4 infant patients with complex congenital heart disease, who underwent open heart surgery in Xiangya Hospital of Central South University, were diagnosed as heparin-induced thrombocytopenia (HIT). After comprehensive treatments, such as intensive monitoring of the platelet count, close observation of thromboembolic skin lesions and close monitoring of argatroban therapy, 3 patients were cured and 1 died. HIT is rare but serious in patients who received heparin therapy. The incidence of mortality and thrombosis is very high. Early identification and diagnosis of high-risk groups can improve the prognosis.


Assuntos
Anticoagulantes/efeitos adversos , Procedimentos Cirúrgicos Cardíacos , Heparina/efeitos adversos , Trombocitopenia/induzido quimicamente , Arginina/análogos & derivados , Humanos , Incidência , Lactente , Ácidos Pipecólicos/uso terapêutico , Contagem de Plaquetas , Prognóstico , Sulfonamidas , Trombose
11.
Clin Interv Aging ; 19: 357-366, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464597

RESUMO

Purpose: Previous research has consistently shown that self-perception of aging (SPA) is an important predictor of health and longevity, while Chinese rural elderly patients with hypertension had poorer SPA. Whether it was associated with their mortality kept unknown. The objective of this study was to investigate the long-term mortality and analyze the association between SPA and this mortality in the specific context of rural elderly patients with hypertension. Patients and Methods: This study is a longitudinal investigation of the mortality in elderly patients with hypertension in rural Suzhou, China. Sociodemographic and clinical data, SPA, and six-year mortality were investigated. We used binary logistic regression and subgroup analyses to assess the effect of SPA at baseline on six-year mortality. Results: A total of 280 hypertensive patients aged 60 years and older participated in the study, of whom 21 died, with a six-year mortality rate of 7.5%. After controlling for covariates, the "Emotional representation" dimension (OR=2.824, 95% CI:1.034-7.712) in SPA remained a risk factor for death. In subgroup analyses of the group aged 75 years and older, high scores on the "Timeline cyclical" (OR=14.125, 95% CI: 1.258-158.593) and "Emotional representations" (OR=2.567, 95% CI:1.066-6.182) dimensions were associated with a higher risk of death, while weekly nut intake may have mitigated the negative SPA effect on mortality. Conclusion: Poorer self-perception of aging was associated with a high risk of mortality in rural elderly patients with hypertension, while the habit of weekly nut intake might help reduce this risk in the group aged 75 years or older.


Assuntos
Hipertensão , Nozes , Idoso , Humanos , Pessoa de Meia-Idade , Hipertensão/psicologia , Envelhecimento/psicologia , China/epidemiologia , Autoimagem
12.
Chem Asian J ; 19(12): e202400180, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38650439

RESUMO

This review explores the potential of using different types of ash, namely fly ash, biomass ash, and coal ash etc., as mediums for CO2 capture and sequestration. The diverse origins of these ash types - municipal waste, organic biomass, and coal combustion - impart unique physicochemical properties that influence their suitability and efficiency in CO2 absorption. This review first discusses the environmental and economic implications of using ash wastes, emphasizing the reduction in landfill usage and the transformation of waste into value-added products. Then the chemical/physical treatments of ash wastes and their inherent capabilities in binding or reacting with CO2 are introduced, along with current methodologies utilize these ashes for CO2 sequestration, including mineral carbonation and direct air capture techniques. The application of using ash wastes for CO2 capture are highlighted, followed by the discussion regarding challenges associated with ash-based CO2 absorption approach. Finally, the article projects into the future, proposing innovative approaches and technological advancements needed to enhance the efficacy of ash in combating the increasing CO2 levels. By providing a comprehensive analysis of current strategies and envisioning future prospects, this review aims to contribute to the field of sustainable CO2 absorption and environmental management.

13.
World J Gastrointest Surg ; 16(5): 1271-1279, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38817284

RESUMO

BACKGROUND: Da Vinci Robotics-assisted total mesorectal excision (TME) surgery for rectal cancer is becoming more widely used. There is no strong evidence that robotic-assisted surgery and laparoscopic surgery have similar outcomes in elderly patients with TME for rectal cancer. AIM: To determine the improved oncological outcomes and short-term efficacy of robot-assisted surgery in elderly patients undergoing TME surgery. METHODS: A retrospective study of the clinical pathology and follow-up of elderly patients who underwent TME surgery at the Department of Gastrointestinal Oncology at the Affiliated Hospital of Nanjing University of Chinese Medicine was conducted from March 2020 through September 2023. The patients were divided into a robot-assisted group (the R-TME group) and a laparoscopic group (the L-TME group), and the short-term efficacy of the two groups was compared. RESULTS: There were 45 elderly patients (≥ 60 years) in the R-TME group and 50 elderly patients (≥ 60 years) in the L-TME group. There were no differences in demographics, conversion rates, or postoperative complication rates. The L-TME group had a longer surgical time than the R-TME group [145 (125, 187.5) vs 180 (148.75, 206.25) min, P = 0.005), and the first postoperative meal time in the L-TME group was longer than that in the R-TME (4 vs 3 d, P = 0.048). Among the sex and body mass index (BMI) subgroups, the R-TME group had better outcomes than did the L-TME group in terms of operation time (P = 0.042) and intraoperative assessment of bleeding (P = 0.042). In the high BMI group, catheter removal occurred earlier in the R-TME group than in the L-TME group (3 vs 4 d, P = 0.001), and autonomous voiding function was restored. CONCLUSION: The curative effect and short-term efficacy of robot-assisted TME surgery for elderly patients with rectal cancer are similar to those of laparoscopic TME surgery; however, robotic-assisted surgery has better short-term outcomes for individuals with risk factors such as obesity and pelvic stenosis. Optimizing the learning curve can shorten the operation time, reduce the recovery time of gastrointestinal function, and improve the prognosis.

14.
Nanoscale ; 16(7): 3269-3292, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38265441

RESUMO

Presently, the rapid depletion of resources and drastic climate change highlight the importance of sustainable development. In this case, nanochitin derived from chitin, the second most abundant renewable polymer in the world, possesses numerous advantages, including toughness, easy processability and biodegradability. Furthermore, it exhibits better dispersibility in various solvents and higher reactivity than chitin owing to its increased surface area to volume ratio. Additionally, it is the only natural polysaccharide that contains nitrogen. Therefore, it is valuable to further develop this innovative technology. This review summarizes the recent developments in nanochitin and specifically identifies sustainable strategies for its preparation. Additionally, the different biomass sources that can be exploited for the extraction of nanochitin are highlighted. More importantly, the life cycle assessment of nanochitin preparation is discussed, followed by its applications in advanced manufacturing and perspectives on the valorization of chitin waste.

15.
ACS Omega ; 9(7): 7452-7462, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38405529

RESUMO

Semiconductor quantum dots (QDs) have been used in a variety of applications ranging from optoelectronics to biodiagnostic fields, primarily due to their size dependent fluorescent nature. CdSe nanocrystals (NCs) are generally synthesized via a hot injection method in an organic solvent. However, such NCs are insoluble in water and therefore preclude the direct usage toward biological systems. Thus, the preparation of more biocompatible water-soluble QDs with a high photoluminescent quantum yield (PLQY) is extremely important for imaging applications. Although previous literature has detailed on the synthesis of CdSe NCs in water, they suffer from poor size distribution and very low PLQY. The complex formation mechanism of CdSe NCs in an aqueous environment adversely affects the quality of NCs due to the presence of OH-, H+, and H2O moieties. Here in this article, we have presented the facile hydrothermal approach to obtain size tunable (2.9-5.1 nm), aqueous CdSe NCs with a narrow emission profile having ∼40 nm fwhm with 56% PLQY. Physicochemical properties of the synthesized water-soluble CdSe NCs were studied with the help of UV-vis, PL, XRD, FTIR, XPS, and HR-TEM analysis. Furthermore, the surface of the synthesized CdSe NCs was modified with d-glucosamine via EDC and NHS coupling to obtain a stable, biocompatible bioimaging probe. Furthermore, we demonstrated that their successful bioconjugation with glucosamine could facilitate effective internalization into the cellular matrix.

16.
Nat Commun ; 15(1): 3892, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719816

RESUMO

As a sustainable alternative to fossil fuel-based manufacture of bulk oxygenates, electrochemical synthesis using CO and H2O as raw materials at ambient conditions offers immense appeal. However, the upscaling of the electrosynthesis of oxygenates encounters kinetic bottlenecks arising from the competing hydrogen evolution reaction with the selective production of ethylene. Herein, a catalytic relay system that can perform in tandem CO capture, activation, intermediate transfer and enrichment on a Cu-Ag composite catalyst is used for attaining high yield CO-to-oxygenates electrosynthesis at high current densities. The composite catalyst Cu/30Ag (molar ratio of Cu to Ag is 7:3) enables high efficiency CO-to-oxygenates conversion, attaining a maximum partial current density for oxygenates of 800 mA cm-2 at an applied current density of 1200 mA cm-2, and with 67 % selectivity. The ability to finely control the production of ethylene and oxygenates highlights the principle of efficient catalyst design based on the relay mechanism.

17.
Small Methods ; 8(3): e2301368, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38009516

RESUMO

The presence of toxic organic pollutants in aquatic environments poses significant threats to human health and global ecosystems. Photocatalysis that enables in situ production and activation of H2 O2 presents a promising approach for pollutant removal; however, the processes of H2 O2 production and activation potentially compete for active sites and charge carriers on the photocatalyst surface, leading to limited catalytic performance. Herein, a hierarchical 2D/2D heterojunction nanosphere composed of ultrathin BiOBr and BiOI nanosheets (BiOBr/BiOI) is developed by a one-pot microwave-assisted synthesis to achieve in situ H2 O2 production and activation for efficient photocatalytic wastewater treatment. Various experimental and characterization results reveal that the BiOBr/BiOI heterojunction facilitates efficient electron transfer from BiOBr to BiOI, enabling the one-step two-electron O2 reduction for H2 O2 production. Moreover, the ultrathin BiOI provides abundant active sites for H2 O2 adsorption, promoting in situ H2 O2 activation for •O2 - generation. As a result, the BiOBr/BiOI hybrid exhibits excellent activity for pollutant degradation with an apparent rate constant of 0.141 min-1 , which is 3.8 and 47.3 times that of pristine BiOBr and BiOI, respectively. This work expands the range of the materials suitable for in situ H2 O2 production and activation, paving the way toward sustainable environmental remediation using solar energy.

18.
Chem Asian J ; 18(14): e202300391, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37259695

RESUMO

Phase Change Materials (PCMs) are utilized to regulate temperature and store thermal energy in various industries such as infrastructure, electronics, solar power, and more. However, they face several limitations, such as leakage, poor thermal properties, incompatibility, as well as high flammability. Polyethylene (PE) is one of many polymers explored to enhance the desirable properties of PCMs, due to their versatile properties such as high strength, durability, chemical resistance, and low cost. The combination of PCMs and PE can be used to create composite materials, through micro/nano- encapsulation, melt-blending, formation of composites and with proper additives. They create enhanced thermal energy storage properties and in the meantime, benefited from the mechanical properties of the PE. This review provides a concise summary of the recent developments regarding PE-enhanced PCMs and provides insights into possible topics for further investigation. We summarised enhancement methods based on commonly adopted types of PEs, such as encapsulation, melt-blending, hot pressing, extrusion, and 3D printing. We then elaborate on how these PE-PCM composites are effectively utilised for heat management applications and the potential future directions in energy-saving buildings, electronic devices, and energy storage systems.

19.
Chin Med ; 18(1): 122, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37735401

RESUMO

BACKGROUND: Curdione is a sesquiterpene isolated from Curcumae Rhizoma that possesses high biological activity and extensive pharmacological effects. As a traditional Chinese medicine, Curcumae Rhizoma can inhibit the development of many types of cancer, especially colorectal cancer. However, the anti-colorectal mechanism of its monomer curdione remains unclear. METHODS: Colorectal cancer (CRC) cells were treated with curdione at doses of 12.5 µM, 25 µM, and 50 µM, and then the cells' activity was measured with methyl thiazolyl tetrazolium (MTT). Nude mice were administered different doses of curdione subcutaneously and oxaliplatin by tail vein injection, and then hematoxylin-eosin (HE) staining was adopted to examine tumor histology. Moreover, flow cytometry was applied to detect reactive oxygen species in cells and tissues. Kits were employed to detect the levels of iron ions, malondialdehyde, lipid hydroperoxide, and glutathione. Polymerase chain reaction (PCR) and Western blotting were adopted to detect ferroptosis and m6A modification-related factors. A methylation spot hybridization assay was performed to measure changes in overall methylation. SLC7A11 and HOXA13 were measured by MeRIP-qPCR. The shRNA-METTL14 plasmid was constructed to verify the inhibitory effect of curdione on CRC. RESULTS: A dose-dependent decrease in activity was observed in curdione-treated cells. Curdione increased the accumulation of reactive oxygen species in CRC cells and tumor tissues, greatly enhanced the levels of malondialdehyde, lipid hydroperoxide and Fe2+, and lowered the activity of glutathione. According to the qPCR and Western blot results, curdione promoted the expression of METTL14 and YTHDF2 in CRC cells and tissues, respectively, and decreased the expression of SLC7A11, SLC3A2, HOXA13, and glutathione peroxidase 4. Additionally, in animal experiments, the curdione-treated group showed severe necrosis of tumor cells, as displayed by HE staining. Furthermore, compared with the control group, levels of m6A modifying factors (namely, SLC7A11 and HOXA13) were increased in the tissues after drug intervention. METTL14 knockdown was followed by an increase in CRC cell activity and glutathione levels. However, the levels of reactive oxygen species, malondialdehyde, and iron ions decreased. The expression levels of SLC7A11, SLC3A2, HOXA13, and GPX4 were all increased after METTL14 knockdown. CONCLUSION: The results suggest that curdione induces ferroptosis in CRC by virtue of m6A methylation.

20.
Nanoscale Horiz ; 9(1): 132-142, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37850320

RESUMO

Atomically-thin monolayer WS2 is a promising channel material for next-generation Moore's nanoelectronics owing to its high theoretical room temperature electron mobility and immunity to short channel effect. The high photoluminescence (PL) quantum yield of the monolayer WS2 also makes it highly promising for future high-performance optoelectronics. However, the difficulty in strictly growing monolayer WS2, due to its non-self-limiting growth mechanism, may hinder its industrial development because of the uncontrollable growth kinetics in attaining the high uniformity in thickness and property on the wafer-scale. In this study, we report a scalable process to achieve a 4 inch wafer-scale fully-covered strictly monolayer WS2 by applying the in situ self-limited thinning of multilayer WS2 formed by sulfurization of WOx films. Through a pulsed supply of sulfur precursor vapor under a continuous H2 flow, the self-limited thinning process can effectively trim down the overgrown multilayer WS2 to the monolayer limit without damaging the remaining bottom WS2 monolayer. Density functional theory (DFT) calculations reveal that the self-limited thinning arises from the thermodynamic instability of the WS2 top layers as opposed to a stable bottom monolayer WS2 on sapphire above a vacuum sublimation temperature of WS2. The self-limited thinning approach overcomes the intrinsic limitation of conventional vapor-based growth methods in preventing the 2nd layer WS2 domain nucleation/growth. It also offers additional advantages, such as scalability, simplicity, and possibility for batch processing, thus opening up a new avenue to develop a manufacturing-viable growth technology for the preparation of a strictly-monolayer WS2 on the wafer-scale.

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