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1.
Discov Oncol ; 15(1): 159, 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38735014

RESUMO

BACKGROUND AND AIMS: Chemotherapy resistance in colorectal cancer have been faced with significant challenges in recent years. Particular interest is directed to tumor microenvironment function. Recent work has, identified a small molecule named Divertin that prevents myosin light chain kinase 1(MLCK1) recruitment to the perijunctional actomyosin ring(PAMR), restores barrier function after tumor necrosis factor(TNF)-induced barrier loss and prevents disease progression in experimental inflammatory bowel disease. Studies have shown that MLCK is a potential target for affecting intestinal barrier function, as well as for tumor therapy. However, the relative contributions of MLCK expression and chemotherapy resistance in colorectal cancers have not been defined. METHODS: Statistical analysis of MYLK gene expression differences in colorectal cancer patients and normal population and prognosis results from The Cancer Genome Atlas(TCGA) data. Cell activity was detected by Cell counting Kit-8. Cell proliferation was detected by monoclonal plate. The apoptosis was detected by flow cytometry and western blot. Determine the role of MLCK1 in inducing 5-Fluorouracil(5-Fu) resistance in colorectal cancer cells was detected by overexpression of MLCK1 and knock-down expression of MLCK1. RESULTS: MLCK1 is expressed at different levels in different colorectal cancer cells, high MLCK1 expressing cell lines are less sensitive to 5-Fu, and low MLCK1 expressing cell lines are more sensitive to 5-Fu. MLCK1 high expression enhances resistance to 5-Fu in colorectal cancer cells and the sensitivity to 5-Fu was increased after knocking down the expression of MLCK1, that might be closely correlated to TNFR2/NF-κB pathway. CONCLUSIONS: MLCK1 high expression can enhance resistance to 5-Fu in colorectal cancer cells and the sensitivity to 5-Fu was increased after knocking down the expression of MLCK1, that might be closely correlated to TNFR2/NF-κB pathway, which will provide a new method for the treatment of colorectal cancer patients who are resistant to 5-Fu chemotherapy.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38634621

RESUMO

Background: Oxidative stress has been implicated in the pathogenesis of polycystic ovarian syndrome (PCOS). To develop novel antioxidant drugs, it is necessary to explore the key regulatory molecules involved in oxidative stress in PCOS. Plasma YKL-40 levels are elevated in patients with PCOS; however, its role remains unclear. Methods: The follicular fluids of 20 women with PCOS and 12 control subjects with normal ovarian function were collected, and YKL-40 in follicular fluids was measured by enzyme-linked immunosorbent assay. A letrozole-induced PCOS rat model was established and the expression level of YKL-40 in the ovaries was detected by immunohistochemistry. KGN cells were treated with H2O2 to generate an ovarian granulosa cell (OGC) model of oxidative stress. The siRNA was transfected into the cells for knockdown. The effect of YKL-40 knockdown on H2O2-treated KGN cells was evaluated by measuring proliferation, apoptosis, activities of T-SOD, GSH-Px, and CAT, levels of MDA, IL-1ß, IL-6, IL-8, and TNF-α, and the PI3K/AKT/NF-κB signaling pathway. Results: YKL-40 levels were elevated in the follicular fluids of women with PCOS compared with control subjects with normal ovarian function. The expression level of YKL-40 in the ovaries of rats with PCOS is obviously higher than that in the ovaries of the control group rats. H2O2 treatment enhanced YKL-40 mRNA expression and protein secretion. YKL-40 knockdown enhanced cell proliferation and antioxidant capacity while decreasing apoptosis and inflammatory factor levels in KGN cells following H2O2 treatment. The knockdown activated the PI3K/AKT signaling pathway and suppressed NF-κB nuclear translocation from the cytoplasm. Conclusion: YKL-40 levels were elevated in the follicular fluids of women with PCOS and the ovaries of rats with PCOS. YKL-40 expression can be induced by oxidative stress, and YKL-40 knockdown can decrease oxidative stress damage in OGCs.

4.
Immunology ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637948

RESUMO

Immune cell infiltration is a significant pathological process in abdominal aortic aneurysms (AAA). T cells, particularly CD4+ T cells, are essential immune cells responsible for substantial infiltration of the aorta. Regulatory T cells (Tregs) in AAA have been identified as tissue-specific; however, the time, location, and mechanism of acquiring the tissue-specific phenotype are still unknown. Using single-cell RNA sequencing (scRNA-seq) on CD4+ T cells from the AAA aorta and spleen, we discovered heterogeneity among CD4+ T cells and identified activated, proliferating and developed aorta Tregs. These Tregs originate in the peripheral tissues and acquire the tissue-specific phenotype in the aorta. The identification of precursors for Tregs in AAA provides new insight into the pathogenesis of AAA.

5.
RSC Adv ; 14(15): 10209-10218, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38544936

RESUMO

In this study, we discuss the tunability of valley splitting using first-principles calculations with a monolayer MoTe2 and layered ferromagnetic MnS2 heterostructure as an example. We observe that, due to the magnetic proximity effect (MPE) at the interface, a monolayer of MoTe2 can exhibit a significant valley splitting of 55.2 meV. The production of the interlayer dipoles with spin-adapted configuration could be the origin of MPE at the interface. Furthermore, the valley splitting can be regulated continuously by the perpendicular electric field and biaxial strain. Interestingly, the valley splitting increases with the increasing induced magnetic moments in MoTe2 by applying an electric field while the inverse laws are presented by applying biaxial strains, which indicates that the mechanisms of valley splitting manipulating in these two ways are quite different. The calculation results suggest that the electric field influences the electric dipole distributions at the interface, which determines the induced magnetic moments in monolayer MoTe2, and results in valley splitting variations. However, biaxial strains not only affect MPE at the interface but also the intrinsic spin splitting caused by spin-orbital coupling (SOC) effects of monolayer MoTe2 itself and the latter is even the dominating mechanism of valley splitting variations.

6.
Global Spine J ; : 21925682241235894, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38406860

RESUMO

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: The goal of this study was to develop a useful clinical prediction nomogram to accurately predict the cancer-specific survival (CSS) of patients with primary spinal cord tumor (SCT), thereby formulating scientific prevention and aiding clinical decision-making. METHODS: In this study, patients with SCT diagnoses from the surveillance, epidemiology, and end results (SEER) database (2000-2018) were taken into account. Initially, a nomogram was created using the CSS-associated independent factors that were determined from both univariate and multivariable Cox regression analyses. Furthermore, the nomogram's capacity for calibration, ability to discriminate, and actual clinical effectiveness were assessed through calibration curves, receiver operating characteristic (ROC) curves, and decision curve analysis (DCA), respectively. Finally, a strategy for categorizing SCT patients' risk was developed. RESULTS: This study included 909 SCT individuals. A novel nomogram was developed to forecast SCT patients' CSS, taking into account age, histological type, tumor grade, tumor stage, and radiotherapy. These factors were identified as independent prognostic indicators for CSS in SCT patients. Elderly SCT patients with distant metastasis, advanced tumor grade, received radiotherapy, and confirmed lymphoma have a poor prognosis. Meanwhile, the risk classification system could differentiate SCT patients and realize targeted management. CONCLUSIONS: The developed nomogram has the ability to accurately forecast the CSS in SCT individuals, aiding in precise decision-making during clinical practice, enhancing health planning, maximizing treatment advantages, and ultimately improving patient prognosis.

7.
Inorg Chem ; 63(9): 4404-4411, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38379507

RESUMO

With the rapid development of 5G communication technology, microwave dielectric ceramics with high dielectric constants are very conducive to the miniaturization of passive devices. Here, Ba3Ti4-x(Ni1/3Nb2/3)xNb4O21 (BTN ∼ NN, 0.03 ≤ x ≤ 0.15) ceramics with hexagonal phases are synthesized via the solid-phase route. The composite (Ni1/3Nb2/3)4+ ion substitution strategy can substantially improve the microwave dielectric properties of the Ba3Ti4Nb4O21 (BTN) ceramic. The εr and Q × f values depend on the ionicity (Nb-O bonds) and lattice energies (Nb(1)-O3 and Nb(1)-O2(1) bonds). The microwave dielectric properties of the BTN ∼ NN (x = 0.09) ceramic sintered at 1250 °C are εr = 60.3, Q × f = 22073 GHz, and τf = 78.1 ppm/°C. A miniaturized all-ceramic radome (@400 mm × 400 mm × 8 mm) for 5G beam-splitting function is designed and demonstrated using this ceramic. Compared to other radomes designed for other work utilizing low εr, the size of this radome has been reduced by 3/7. The reflection coefficients of the beam splitting function are all 0.73, and the phase shifts are all 360°. This work contributes to the development of miniaturized passive devices from a materials point of view.

8.
BMC Public Health ; 24(1): 533, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378488

RESUMO

BACKGROUND: Previous studies of singletons evaluating prenatal phthalate exposure and early neurodevelopment reported mixed results and the associations could be biased by parental, obstetrical, and genetic factors. METHODS: A co-twin control design was employed to test whether prenatal phthalate exposure was associated with children's neurocognitive development. We collected information from 97 mother-twin pairs enrolled in the Wuhan Twin Birth Cohort between March 2016 and October 2018. Fourteen phthalate metabolites were measured in maternal urine collected at each trimester. Neurodevelopmental differences in twins at the age of two were examined as the outcome of interest. Multiple informant model was used to examine the covariate-adjusted associations of prenatal phthalate exposure with mental development index (MDI) and psychomotor development index (PDI) scores assessed at 2 years of age based on Bayley Scales of Infant Development (Second Edition). This model also helps to identify the exposure window of susceptibility. RESULTS: Maternal urinary levels of mono-2-ethyl-5-oxohexyl phthalate (MEOHP) (ß = 1.91, 95% CI: 0.43, 3.39), mono (2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) (ß = 1.56, 95% CI: 0.33, 2.79), and the sum of di-(2-ethylhexyl) phthalate metabolites (∑DEHP) (ß = 1.85, 95% CI: 0.39, 3.31) during the first trimester showed the strongest and significant positive associations with intra-twin MDI difference. When stratified with twin chorionicity, the positive associations of monoethyl phthalate (MEP), monoisobutyl phthalate (MiBP), mono-n-butyl phthalate (MBP), monobenzyl phthalate (MBzP), individual DEHP metabolites, and ∑DEHP exposure during pregnancy with intra-twin neurodevelopmental differences were more significant in monochorionic diamniotic (MCDA) twins than those in dichorionic diamniotic (DCDA) twins. CONCLUSIONS: Neurodevelopmental differences in MCDA twins were strongly associated with prenatal phthalate exposure. Our findings warrant further confirmation in longitudinal studies with larger sample sizes.


Assuntos
Poluentes Ambientais , Ácidos Ftálicos , Criança , Lactente , Gravidez , Feminino , Humanos , Ácidos Ftálicos/toxicidade , Estudos Longitudinais , Trimestres da Gravidez , Primeiro Trimestre da Gravidez , Mães , Exposição Ambiental , Poluentes Ambientais/toxicidade , Exposição Materna/efeitos adversos
9.
Nat Prod Res ; : 1-10, 2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38343285

RESUMO

Thirteen nitrogen-containing derivatives of 3,11-dioxo-olean-12-en-30-oic acid were synthesised by introducing various amino acids and nitrogen-containing heterocyclic groups at the 30-carboxyl group, starting from 18ß-glycyrrhetinic acid. Among the 13 derivatives, 10 exhibited inhibitory activity against HIV-1 PR, with IC50 values ranging from 0.19 to 0.94 mM. Notably, derivatives 2, 3 and 5 displayed relatively moderate inhibitory activity, with IC50 values below 0.24 mM. Molecular docking studies provided further insights into the interaction between derivatives (2, 3 and 5) and the active sites of HIV-1 PR. The results revealed favourable hydrophobic-hydrophobic and hydrogen bonding interactions, with docking scores ranging from -6.22 to -7.00 and glide emodel values from -62.9 to -48.6 (kcal/mol). These findings underscore the potential of derivatives 2, 3 and 5 as promising candidates for the development of HIV-1 PR inhibitors.

10.
Cancer Metab ; 12(1): 6, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365771

RESUMO

BACKGROUND: Metastasis is the leading cause of death among prostate cancer (PCa) patients. Obesity is associated with both PCa-specific and all-cause mortality. High-fat diet (HFD) is a risk factor contributing to obesity. However, the association of HFD with PCa metastasis and its underlying mechanisms are unclear. METHODS: Tumor xenografts were conducted by intrasplenic injections. The ability of migration or invasion was detected by transwell assay. The expression levels of RPS27 were detected by QRT-PCR and western blot. RESULTS: The present study verified the increase in PCa metastasis caused by HFD in mice. Bioinformatics analysis demonstrated increased RPS27 in the experimentally induced PCa in HFD mice, indicating that it is an unfavorable prognostic factor. Intrasplenic injections were used to demonstrate that RPS27 overexpression promotes, while RPS27 knockdown significantly reduces, PCa liver metastasis. Moreover, RPS27 inhibition suppresses the effects of HFD on PCa metastasis. Further mRNA sequencing analysis revealed that RPS27 promotes PCa metastasis by selectively enhancing the expression of various genes. CONCLUSION: Our findings indicate that HFD increases the risk of PCa metastasis by elevating RPS27 expression and, subsequently, the expression of genes involved in PRAD progression. Therefore, RPS27 may serve as a novel target for the diagnosis and treatment of metastatic PCa.

11.
Int J Biol Macromol ; 259(Pt 2): 129298, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199555

RESUMO

Seeking safe and environmentally friendly natural immunomodulators is a pressing requirement of humanity. This study investigated the differential binding characteristics of two polar polyphenols (PP), namely epicatechin (EC) and chlorogenic acid (CA), to ovotransferrin (OVT), and explored the relationship between structural transformations and immunomodulatory activity of OVT-PP complexes. Results showed that CA exhibited a stronger affinity for OVT than EC, mainly driven by hydrogen bonds and van der Waals forces. Complexation-induced conformational variations in OVT, including static fluorescence quenching, increased microenvironment polarity surrounding tryptophan and tyrosine residues, and the transition from disordered α-helix to stable ß-sheet. Furthermore, the structural conformation transformation of OVT-PP complexes facilitated the enhancement of immunomodulatory activity, with the OVT-CA (10:2) complex demonstrating the best immunomodulatory activity. Principal component analysis (PCA) and Pearson correlation analysis revealed the immunomodulatory activities of the OVT-PP complexes were influenced by surface hydrophobicity (negatively correlated), ß-sheet percentage and polyphenol binding constants. It could be inferred that PP complexation increased the surface polarity of OVT, consequently enhancing its immunomodulatory activity by promoting cell membrane affinity and antigen recognition. This study provides valuable guidance for effectively utilizing polyphenol-protein complexes in enhancing immunomodulatory activity.


Assuntos
Catequina , Conalbumina , Ácido Clorogênico , Fatores Imunológicos/farmacologia , Polifenóis/farmacologia
12.
BMC Surg ; 24(1): 26, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238695

RESUMO

BACKGROUND: Abdominal distension is a relatively common complication in postoperative lung cancer patients, which affects patients' early postoperative recovery to varying degrees. However, the current status of the incidence of abdominal distension in postoperative lung cancer patients and the affecting factors are not well understood. This study aims at exploring the incidence of abdominal distension in postoperative lung cancer patients in ICU based on real-world data and analyzing its influencing factors. METHODS: A retrospective cohort study was conducted, encompassing patients who underwent lung cancer resections in the Lung Cancer Center of West China Hospital of Sichuan University from April 2020 to April 2021. Nevertheless, patients younger than 18 years and those whose information was limited in medical records were excluded. All data were obtained from the hospital HIS system. In this study, the influencing factors of abdominal distension were analyzed by univariate analysis and multiple logistic regression methods. RESULTS: A total of 1317 patients met eligibility criteria, and were divided into the abdominal distended group and the non-distended group according to whether abdominal distension occurred after surgery. Abdominal distension occurred in a total of 182 cases(13.8%). The results of the univariate analysis showed that, compared with the non-distended group, the abdominal distended group had these features as follows: more women (P = 0.021), older (P = 0.000), lower BMI (P = 0.000), longer operation duration (P = 0.031), more patients with open thoracotomy (P = 0.000), more patients with pneumonectomy (p = 0.002), more patients with neoadjuvant chemotherapy (P = 0.000), more days of hospitalization on average (P = 0.000), and higher costs of hospitalization on average (P = 0.032). Multifactor logistic regression analysis showed that sex (OR = 0.526; 95% CI = 0.378 ~0.731), age (OR = 1.154; 95%CI = 1.022 ~1.304) and surgical approach (OR = 4.010; 95%CI = 2.781 ~5.781) were independent influencing factors for the occurrence of abdominal distension in patients after lung cancer surgery in ICU. CONCLUSIONS: The incidence of abdominal distension was high in postoperative lung cancer patients in ICU, and female, older and patients with open thoracotomy were more likely to experience abdominal distension. TRIAL REGISTRATION: The study was approved by the Chinese Clinical Trials Registry (registration number was ChiCTR2200061370).


Assuntos
Neoplasias Pulmonares , Feminino , Humanos , Incidência , Unidades de Terapia Intensiva , Neoplasias Pulmonares/cirurgia , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Masculino
13.
FASEB J ; 38(1): e23386, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38112398

RESUMO

CD4+ T-cell counts are increased and activated in patients with chronic heart failure (CHF), whereas regulatory T-cell (Treg) expansion is inhibited, probably due to aberrant T-cell receptor (TCR) signaling. TCR signaling is affected by protein tyrosine phosphatase nonreceptor type 22 (PTPN22) in autoimmune disorders, but whether PTPN22 influences TCR signaling in CHF remains unclear. This observational case-control study included 45 patients with CHF [18 patients with ischemic heart failure versus 27 patients with nonischemic heart failure (NIHF)] and 16 non-CHF controls. We used flow cytometry to detect PTPN22 expression, tyrosine phosphorylation levels, zeta-chain-associated protein kinase, 70 kDa (ZAP-70) inhibitory residue tyrosine 292 and 319 phosphorylation levels, and CD4+ T cell and Treg proportions. We conducted lentivirus-mediated PTPN22 RNA silencing in isolated CD4+ T cells. PTPN22 expression increased in the CD4+ T cells of patients with CHF compared with that in controls. PTPN22 expression was positively correlated with left ventricular end-diastolic diameter and type B natriuretic peptide but negatively correlated with left ventricular ejection fraction in the NIHF group. ZAP-70 tyrosine 292 phosphorylation was decreased, which correlated positively with PTPN22 overexpression in patients with NIHF and promoted early TCR signaling. PTPN22 silencing induced Treg differentiation in CD4+ T cells from patients with CHF, which might account for the reduced frequency of peripheral Tregs in these patients. PTPN22 is a potent immunomodulator in CHF and might play an essential role in the development of CHF by promoting early TCR signaling and impairing Treg differentiation from CD4+ T cells.


Assuntos
Insuficiência Cardíaca , Receptores de Antígenos de Linfócitos T , Humanos , Estudos de Casos e Controles , Volume Sistólico , Receptores de Antígenos de Linfócitos T/metabolismo , Função Ventricular Esquerda , Proteínas Tirosina Fosfatases , Linfócitos T Reguladores , Tirosina , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética
14.
ACS Appl Mater Interfaces ; 15(51): 59600-59609, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38091576

RESUMO

High efficiency, high frequency, low error, and low latency of wavefront modulation are challenges that must be addressed simultaneously in 5G/6G communication systems. In order to cope with these challenges, novel Li2Mg2-xZnxMo3O12 (x = 0.00-0.08) ceramics are prepared by a solid-state reaction method. The microwave dielectric properties (εr = 8.7, Q × f = 61,312 GHz, τf = -59.1 ppm/°C) and terahertz transmission properties (εr1 = 8.3, tanδ1 = 0.00908, Tamplitude = 0.673, Δphase = 27.65°) of this ceramic (x = 0.06, 625 °C) are effectively enhanced by Zn2+. The chemical compatibility between this ceramic and the Al electrode is demonstrated. The reflection amplitude of this ceramic combined with the Al electrode at 0.5 THz is revealed, and the error between simulation and experiment is only 0.06. A terahertz reflective device for wavefront modulation is designed and demonstrated by using this ceramic and Al electrode. This device can deflect the wavefront of cross-polarized waves and has a certain isolation effect on co-polarized waves. This work accelerates the development of dielectric ceramics and ultralow temperature cofired ceramics technology in the terahertz field.

15.
Opt Express ; 31(24): 40308-40316, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38041335

RESUMO

In this paper, we propose a precision method to measure the chiroptical signal of Artemisinin solutions using the photonic spin Hall effect (PSHE) on the Ce:YIG-YIG-SiO2 structure as a probe. The effects of transmission distance, incident angles, applied magnetic fields of different directions, and beam waist of light on the weak measurement system are analytically investigated through simulations. It is found that decreasing the beam waist of the incident spot, increasing the incident angle, increasing the transmission distance, and adding a longitudinal magnetic field is conducive to enhancing the amplification transverse shift of PSHE, thus the measurement sensitivity is greatly improved. Based on the optimal weak measurement scheme, the detection limit for concentration measurement of artemisinin based on optical rotatory (OR) was reduced to 0.05 mg/ml. The measurement precision of the OR angle has been improved to 10-7rad.

16.
Cancer Imaging ; 23(1): 122, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38102702

RESUMO

BACKGROUND: This study was designed to perform a comparative analysis between endoscopic ultrasonography (EUS) and double contrast-enhanced ultrasonography (DCEUS) for the preoperative diagnosis of gastric stromal tumors (GSTs). METHODS: A retrospective study was conducted involving 139 patients with histologically confirmed GSTs. All patients preoperatively underwent DCEUS and EUS. The pathology reports were treated as the baseline and were retrospectively compared with the findings of EUS and DCEUS. RESULTS: Of the 139 lesions, 120 and 113 were correctly identified by DCEUS and EUS, respectively, with an accuracy of 86.3% and 81.3%. The results revealed an insignificant difference between these two methods (p = 0.189). CONCLUSIONS: DCEUS can display not only the locations, sizes, shapes, borders, internal echoes, but also show the blood perfusion patterns of GSTs. It is a highly accurate, noninvasive, and convenient method to be used at the pre-treatment stage.


Assuntos
Endossonografia , Neoplasias Gástricas , Humanos , Estudos Retrospectivos , Meios de Contraste , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Ultrassonografia/métodos
17.
J Mech Behav Biomed Mater ; 148: 106162, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37837874

RESUMO

Electrospun fibres have been widely used as skin dressings due to their unique structur. However, due to the lack of intrinsic antimicrobial activity, it is easy for the wound to become infected. Bacterial infection, which leads to chronic inflammation, severely hinders the normal process of skin regeneration. In this study, a polyvinyl alcohol/chitosan (PVA/CS) composite films with chemical sterilization and near-infrared (NIR) photothermal antibacterial activity was fabricated by electrospinning. Graphene oxide (GO), a photosensitiser, was incorporated into the films, and lanthanum chloride (Lacl3) as a chemical antibacterial agent was also doped in the electrospun films. The structure, morphology, mechanical properties, wettability, and antimicrobial and photothermal antibacterial activity of the PVA/CS-based fibre films were investigated. The results showed that the addition of Lacl3 to the PVA/CS/GO nanofibres (PVA/CS/GO-La) improved the hydrophilicity, tensile strength and resistance to elastic deformation of the nanofibres. The PVA/CS/GO-La12.5 mM sample exhibited the best antibacterial performance, showing high inhibition against Staphylococcus aureus (82% antibacterial efficacy) and Escherichia coli (99.7% antibacterial efficacy). Furthermore, the antibacterial efficacy of the films surface was further enhanced after exposure to NIR light (808 nm, 0.01 W) for 20 min. In addition, the nanofibre films showed no cytotoxicity against human skin fibroblasts (HSFs), indicating its potential application in the field of broad-spectrum antibacterial materials.


Assuntos
Anti-Infecciosos , Quitosana , Nanofibras , Humanos , Quitosana/química , Álcool de Polivinil/química , Nanofibras/química , Antibacterianos/farmacologia , Antibacterianos/química , Anti-Infecciosos/farmacologia , Bandagens , Escherichia coli
18.
J Environ Manage ; 348: 119426, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37879178

RESUMO

Clean energy is urgently needed to realize mining projects' sustainable development (SD). This study aims to discuss the clean energy development path and the related issues of SD in the ecological environment driven by big data for mining projects. This study adopts a comprehensive research approach, including a literature review, case analysis, and model construction. Firstly, an in-depth literature review of the development status of clean energy is carried out, and the existing research results and technology applications are explored. Secondly, some typical mining projects are selected as cases to discuss the practice and effect of their clean energy application. Finally, the corresponding clean energy development path and the SD analysis model of the ecological environment are constructed based on big data technology to evaluate the feasibility and potential benefits of promoting and applying clean energy in mining projects. (1) It is observed that under different Gross Domestic Product (GDP) growth rates, the new and cumulative installed capacities of wind energy show an increasing trend. In 2022, under the low GDP growth rate, the cumulative installed capacity of global wind energy was 370.60 Gigawatt (GW), and the new installed capacity was 45 GW. With the high GDP growth rate, the cumulative and new installed capacities were 367.83 GW and 46 GW. As the economy grows, new wind energy capacity is expected to increase significantly by 2030. In 2046, 2047, and 2050, carbon dioxide (CO2) emissions reductions are projected to be 8183.35, 8539.22, and 9842.73 Million tons (Mt) (low scenario), 8750.68, 9087.16, and 10,468.75 Mt (medium scenario), and 9083.03, 9458.86, and 10,879.58 Mt (high scenario). By 2060, it is expected that CO2 emissions reduction will continue to increase. (2) The proposed clean energy development path model has achieved a good effect. Through this study, it is hoped to provide empirical support and decision-making reference for the development of mining projects in clean energy, and promote the SD of the mining industry, thus achieving a win-win situation of economic and ecological benefits. This is of great significance for protecting the ecological environment and realizing the sustainable utilization of resources.


Assuntos
Dióxido de Carbono , Desenvolvimento Sustentável , Big Data , Mineração , Desenvolvimento Econômico , Energia Renovável
19.
J Math Biol ; 87(4): 62, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37736867

RESUMO

Our earlier work in Nguyen et al. (Maximizing metapopulation growth rate and biomass in stream networks. arXiv preprint arXiv:2306.05555 , 2023) shows that concentrating resources on the upstream end tends to maximize the total biomass in a metapopulation model for a stream species. In this paper, we continue our research direction by further considering a Lotka-Volterra competition patch model for two stream species. We show that the species whose resource allocations maximize the total biomass has the competitive advantage.


Assuntos
Alocação de Recursos , Biomassa
20.
Opt Lett ; 48(18): 4833-4836, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37707914

RESUMO

The properties of traditional Fresnel zone plates have been greatly enhanced by metasurfaces, which allow the control of polarization, orbital angular momentum, or other parameters on the basis of focusing. In this Letter, a new, to the best of our knowledge, method for circularly polarized wave manipulation based on a zone plate is proposed. Chiral meta-atoms and binary geometric phase are used for the simultaneous focusing of reflected and transmitted terahertz waves. The silicon-based dielectric chiral units, which show great performance of spin-selective transmission near 0.54 THz, separate the orthogonal circularly polarized components. A binary Pancharatnam-Berry (P-B) phase gradient is obtained by rotating the unit 90 degrees, then the phase zone plate can be easily designed. The simulation results show that the proposed chiral metasurface zone plate has the function of reflection-transmission separation and focusing for the circularly polarized terahertz waves. In addition, we also demonstrate the possibility of using a 1064-nm continuous infrared laser to adjust the intensity of our devices, based on photo-generated carriers in silicon. The design principle of the chiral metasurface zone plates can be extended to other wavelengths, providing new ideas for the regulation of circularly polarized light.

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