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1.
Lipids Health Dis ; 23(1): 180, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862993

RESUMO

BACKGROUND: The management of male infertility continues to encounter an array of challenges and constraints, necessitating an in-depth exploration of novel therapeutic targets to enhance its efficacy. As an eight-carbon medium-chain fatty acid, octanoic acid (OCA) shows promise for improving health, yet its impact on spermatogenesis remains inadequately researched. METHODS: Mass spectrometry was performed to determine the fatty acid content and screen for a pivotal lipid component in the serum of patients with severe spermatogenesis disorders. The sperm quality was examined, and histopathological analysis and biotin tracer tests were performed to assess spermatogenesis function and the integrity of the blood-testis barrier (BTB) in vivo. Cell-based in vitro experiments were carried out to investigate the effects of OCA administration on Sertoli cell dysfunction. This research aimed to elucidate the mechanism by which OCA may influence the function of Sertoli cells. RESULTS: A pronounced reduction in OCA content was observed in the serum of patients with severe spermatogenesis disorders, indicating that OCA deficiency is related to spermatogenic disorders. The protective effect of OCA on reproduction was tested in a mouse model of spermatogenic disorder induced by busulfan at a dose 30 mg/kg body weight (BW). The mice in the study were separated into distinct groups and administered varying amounts of OCA, specifically at doses of 32, 64, 128, and 256 mg/kg BW. After evaluating sperm parameters, the most effective dose was determined to be 32 mg/kg BW. In vivo experiments showed that treatment with OCA significantly improved sperm quality, testicular histopathology and BTB integrity, which were damaged by busulfan. Moreover, OCA intervention reduced busulfan-induced oxidative stress and autophagy in mouse testes. In vitro, OCA pretreatment (100 µM) significantly ameliorated Sertoli cell dysfunction by alleviating busulfan (800 µM)-induced oxidative stress and autophagy. Moreover, rapamycin (5 µM)-induced autophagy led to Sertoli cell barrier dysfunction, while OCA administration exerted a protective effect by alleviating autophagy. CONCLUSIONS: This study demonstrated that OCA administration suppressed oxidative stress and autophagy to alleviate busulfan-induced BTB damage. These findings provide a deeper understanding of the toxicology of busulfan and a promising avenue for the development of novel OCA-based therapies for male infertility.


Assuntos
Autofagia , Barreira Hematotesticular , Bussulfano , Caprilatos , Estresse Oxidativo , Células de Sertoli , Espermatogênese , Masculino , Animais , Barreira Hematotesticular/efeitos dos fármacos , Barreira Hematotesticular/metabolismo , Bussulfano/efeitos adversos , Caprilatos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Camundongos , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Humanos , Espermatogênese/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Infertilidade Masculina/tratamento farmacológico , Infertilidade Masculina/induzido quimicamente , Infertilidade Masculina/patologia , Testículo/efeitos dos fármacos , Testículo/patologia , Testículo/metabolismo , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Adulto
2.
Bioact Mater ; 38: 455-471, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38770426

RESUMO

Osteosarcoma is the most common malignant bone tumor without efficient management for improving 5-year event-free survival. Immunotherapy is also limited due to its highly immunosuppressive tumor microenvironment (TME). Pore-forming gasdermins (GSDMs)-mediated pyroptosis has gained increasing concern in reshaping TME, however, the expressions and relationships of GSDMs with osteosarcoma remain unclear. Herein, gasdermin E (GSDME) expression is found to be positively correlated with the prognosis and immune infiltration of osteosarcoma patients, and low GSDME expression was observed. A vector termed as LPAD contains abundant hydroxyl groups for hydrating layer formation was then prepared to deliver the GSDME gene to upregulate protein expression in osteosarcoma for efficient TME reshaping via enhanced pyroptosis induction. Atomistic molecular dynamics simulations analysis proved that the hydroxyl groups increased LPAD hydration abilities by enhancing coulombic interaction. The upregulated GSDME expression together with cleaved caspase-3 provided impressive pyroptosis induction. The pyroptosis further initiated proinflammatory cytokines release, increased immune cell infiltration, activated adaptive immune responses and create a favorable immunogenic hot TME. The study not only confirms the role of GSDME in the immune infiltration and prognosis of osteosarcoma, but also provides a promising strategy for the inhibition of osteosarcoma by pore-forming GSDME gene delivery induced enhanced pyroptosis to reshape the TME of osteosarcoma.

3.
Bioconjug Chem ; 35(5): 604-615, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38661725

RESUMO

Chimeric antigen receptor T-cell (CAR-T cell) therapy has become a promising treatment option for B-cell hematological tumors. However, few optional target antigens and disease relapse due to loss of target antigens limit the broad clinical applicability of CAR-T cells. Here, we conjugated an antibody (Ab) fusion protein, consisting of an Ab domain and a SpyCatcher domain, with the FITC-SpyTag (FITC-ST) peptide to form a bispecific safety switch module using a site-specific conjugation system. We applied the safety switch module to target CD19, PDL1, or Her2-expressing tumor cells by constructing FMC63 (anti-CD19), antiPDL1, or ZHER (anti-Her2)-FITC-ST, respectively. Those switch modules significantly improved the cytotoxic effects of anti-FITC CAR-T cells on tumor cells. Additionally, we obtained the purified CD8+ T cells by optimizing a shorter version of the CD8-binding aptamer to generate anti-FITC CD8-CAR-T cells, which combined with the CD4-FITC-ST switch module (anti-CD4) to eliminate the CD4-positive tumor cells in vitro and in vivo. Overall, we established a novel safety switch module by site-specific conjugation to enhance the antitumor function of universal CAR-T cells, thereby expanding the application scope of CAR-T therapy and improving its safety and efficacy.


Assuntos
Imunoterapia Adotiva , Receptores de Antígenos Quiméricos , Humanos , Animais , Imunoterapia Adotiva/métodos , Camundongos , Receptores de Antígenos Quiméricos/imunologia , Antígenos CD19/imunologia , Linhagem Celular Tumoral , Linfócitos T CD8-Positivos/imunologia , Receptor ErbB-2/imunologia
4.
Medicine (Baltimore) ; 103(11): e37462, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489685

RESUMO

Nanotechnology and nanomaterials have swiftly influenced wound healing, propelling the development of wound-healing nanomaterials. Therefore, it's crucial to gather essential information about prominent researches in this domain. Moreover, identifying primary directions and related frontiers in wound healing and nanomaterials is paramount. This will enhance our comprehension of the current research landscape and foster progress in this field. Retrieved from the Web of Science core database, a total of 838 relevant studies published from 2013 to 2022 were analyzed through bibliometric visualization tools such as CiteSpace, VOSviewer, and Bibliometrics Online Analysis Platform. The annual study count has been rising steadily, primary contributors to this field include China, India, and the United States. The author with the highest output is Zangeneh, Akram, while Grumezescu, Alexandru Mihai garners the most citations. Chinese Academy of Sciences emerges as the leading institution, with Nanomaterials as the predominant journal. The keyword "antibacterial" signals prevailing and forthcoming trends in this domain. This study presents the first scientometric study and bibliometric visualization for wound healing-related nanomaterials, shedding light on research hotspots and trends. Over the course of the decade from 2013 to 2022, enthusiasm for nanomaterials in wound healing research has surged, auguring well for upcoming investigations.


Assuntos
Nanoestruturas , Humanos , Nanotecnologia , Academias e Institutos , Antibacterianos , Cicatrização
6.
Sci Total Environ ; 926: 171956, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38547966

RESUMO

Increasingly frequent extreme rainfall as a result of climate change is strongly damaging the global soil and water environment. However, few studies have focused on daily extreme sediment events (DESE) in heterogeneous karst watersheds based on long-term in-situ observations. This study quantitatively assessed the time effect of DESE on rainfall response, decoupled the impact of environmental factors on DESE by using structural equation modelling, and finally explored the modelling scheme of DESE based on the hybrid model. The results showed that DESE had the highest frequency of occurrence in May-July, with dispersed distribution in the value domain. Rainfall with a time lag of 1 day and a time accumulation of 2 or 3 days was an important contribution to DESE (P < 0.01, R = 0.47-0.68). Combined effects of environmental factors explained 53.6 %-64.1 % of the variation in DESE. Runoff and vegetation exerted the strongest direct and indirect effects on DESE, respectively (ß = 0.66/-0.727). Vegetation was the dominant driver of DESE in Dabanghe and Yejihe (ß = -0.725/-0.758), while the dominant driver in Tongzhihe was climate (ß = 0.743). In the future, the risk of extreme sediments should be prevented and resolved through the comprehensive regulation of multiple paths, such as runoff and vegetation. Hybrid models significantly improved the modelling performance of machine learning models. Generalized additive model-Extreme gradient boost had the best performance, while Partial least squares regression-Extreme gradient boost was the most valuable when considering performance and input data cost. Two methods can be used as recommended solutions for DESE modelling. This study provides new and in-depth insights into DESE in karst watersheds and helps the region develop forward-looking soil and water management models to cope with future extreme erosion hazards.

7.
Bioact Mater ; 34: 204-220, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38235309

RESUMO

Skeletal stem cells (SSC) have gained attentions as candidates for the treatment of osteoarthritis due to their osteochondrogenic capacity. However, the immunomodulatory properties of SSC, especially under delivery operations, have been largely ignored. In the study, we found that Pdpn+ and Grem1+ SSC subpopulations owned immunoregulatory potential, and the single-cell RNA sequencing (scRNA-seq) data suggested that the mechanical activation of microgel carriers on SSC induced the generation of Pdpn+Grem1+Ptgs2+ SSC subpopulation, which was potent at suppressing macrophage inflammation. The microgel carriers promoted the YAP nuclear translocation, and the activated YAP protein was necessary for the increased expression of Ptgs2 and PGE2 in microgels-delivered SSC, which further suppressed the expression of TNF-ɑ, IL-1ß and promoted the expression of IL-10 in macrophages. SSC delivered with microgels yielded better preventive effects on articular lesions and macrophage activation in osteoarthritic rats than SSC without microgels. Chemically blocking the YAP and Ptgs2 in microgels-delivered SSC partially abolished the enhanced protection on articular tissues and suppression on osteoarthritic macrophages. Moreover, microgel carriers significantly prolonged SSC retention time in vivo without increasing SSC implanting into osteoarthritic joints. Together, our study demonstrated that microgel carriers enhanced SSC reprogramming towards immunomodulatory phenotype to regulate macrophage phenotype transformation for effectively osteoarthritic therapy by promoting YAP protein translocation into nucleus. The study not only complement and perfect the immunological mechanisms of SSC-based therapy at the single-cell level, but also provide new insight for microgel carriers in stem cell-based therapy.

8.
Sci Rep ; 14(1): 194, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167411

RESUMO

Determining maintenance demand ahead of mission is crucial to practical weapon maintenance, particularly to regional warship weapon maintenance. Attention is paid only to reliability, and the nature of mission or the consequence of damage is ignored while determining the regional warship weapon maintenance demand. For this reason, a method for determining regional maintenance demand based on simulation is put forward in this paper. Regional weapon maintenance system is first analyzed to build a mission-oriented maintenance demand model with the concept of mission-induced failure. Subsequently, the Anylogic platform is employed because of its advantages including agent modeling simulation and visualized process display. Four types of agent are designed for the regional maintenance system. The process of determining maintenance demand based on simulation is established on this basis. An example is eventually taken to calculate and verify the universality and effectiveness of the simulation model.

9.
Cell Prolif ; 57(2): e13551, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37743695

RESUMO

Busulfan is an antineoplastic, which is always accompanied with the abnormal of spermatogonia self-renewal and differentiation. It has been demonstrated that the omega-3 polyunsaturated fatty acids (PUFAs) benefits mature spermatozoa. However, whether omega-3 can protect endogenous spermatogonia and the detailed mechanisms are still unclear. Evaluate of spermatogenesis function (in vivo) were examined by histopathological analysis, immunofluorescence staining, and western blotting. The levels of lipid metabolites in testicular tissue were determined via liquid chromatography. We investigated the effect of lipid metabolites on Sertoli cells provided paracrine factors to regulate spermatogonia proliferation and differentiation using co-culture system. In our study, we showed that omega-3 PUFAs significantly improved the process of sperm production and elevated the quantity of both undifferentiated Lin28+ spermatogonia and differentiated c-kit+ spermatogonia in a mouse model where spermatogenic function was disrupted by busulfan. Mass spectrometry revealed an increase in the levels of several omega-3 metabolites in the testes of mice fed with omega-3 PUFAs. The eicosapentaenoic acid metabolite 12-hydroxyeicosapentaenoic acid (12-HEPE) up-regulated bone morphogenic protein 4 (BMP4) expression through GPR120-ERK1/2 pathway activation in Sertoli cells and restored spermatogonia proliferation and differentiation. Our study provides evidence that omega-3 PUFAs metabolite 12-HEPE effectively protects spermatogonia and reveals that GPR120 might be a tractable pharmacological target for fertility in men received chemotherapy or severe spermatogenesis dysfunction.


Assuntos
Bussulfano , Sêmen , Humanos , Masculino , Camundongos , Animais , Bussulfano/farmacologia , Bussulfano/metabolismo , Espermatogênese/fisiologia , Espermatogônias , Espermatozoides , Testículo/metabolismo
10.
J Biophotonics ; 17(1): e202300323, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37769060

RESUMO

To achieve high-accuracy urine specific gravity discrimination and guide the design of four-waveband multispectral sensors. A modified combination strategy was attempted to be proposed based on the successive projections algorithm (SPA) and the spectral index (SI) in the present study. First, the SPA was used to select four spectral variables in the full spectra. Second, the four spectral variables were mathematically transformed by SI to obtain SI values. Then, SPA gradually fusions the SI values and establishes models to identify USG. The results showed that the SPA can screen out the four characteristic wavelengths related to the measured sample attributes. SIs can be used to improve the performance of constructed prediction models. The best model only involves four spectral variables and 1 SI value, with high accuracy (91.62%), sensitivity (0.9051), and specificity (0.9667). The results reveal that m-SPA-SI can effectively distinguish USG and provide design guidance for 4-wavelength multispectral sensors.


Assuntos
Algoritmos , Espectroscopia de Luz Próxima ao Infravermelho , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Análise dos Mínimos Quadrados , Gravidade Específica
12.
Am J Hosp Palliat Care ; : 10499091231219254, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38015873

RESUMO

AIMS: Cancer is a leading cause of death worldwide. Approximately 30% of global cancer-related deaths occur in mainland China. However, there is a paucity of information regarding the end-of-life care-seeking behavior of patients with advanced cancer in China. Our study was to investigate end-of-life care-seeking behavior and to quantify the association between sociodemographic characteristics and the location and pattern of end-of-life care. METHODS: We conducted a mortality follow-back survey using caregivers' interviews to estimate the number of individuals pre 1000 who died between 2013 and 2021 in the last 3 months of life. We collected data on hospitalization, outpatient visits, cardiopulmonary resuscitation, palliative care and hospice utilization, and place of death, stratified by age, gender, marital status, household income, residential zone, insurance type, and the primary end-of-life decision-maker of the decedents. RESULTS: We analyzed data from 857 deceased cancer patients, representing an average of 1000 individuals. Among these patients, 861 experienced at least moderate or more severe pain, 774 were hospitalized at least once, 468 received intensive treatment, 389 had at least one outpatient visit, 270 died in the hospital, 236 received cardiopulmonary resuscitation and 99 received specialist hospice care. CONCLUSIONS: Our study provides insights into the end-of-life care-seeking behavior of advanced cancer patients in China and our findings serve as a useful benchmark for estimating the use of end-of-life medical care. It highlights the need for the establishment of an accessible and patient-centered palliative care and hospice system.

13.
World J Oncol ; 14(5): 350-357, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37869238

RESUMO

The utilization of radiotherapy (RT) serves as the principal approach for managing nasopharyngeal carcinoma (NPC). Consequently, it is imperative to investigate the correlation between the radiation microenvironment and radiation resistance in NPC. PubMed and China National Knowledge Infrastructure (CNKI) databases were accessed to perform a search utilizing the English keywords "nasopharyngeal cancer", "radiotherapy", and "microenvironment". The search time spanned from the establishment of the database until January 20, 2023. A total of 82 articles were included. The post-radiation tumor microenvironment (TME), or the radiation microenvironment, includes several components, such as the radiation-immune microenvironment and the radiation-hypoxic microenvironment. The radiation-immune microenvironment includes various factors like immune cells, signaling molecules, and extracellular matrix. RT can reshape the TME, leading to immune responses with both cytotoxic effects (T cells, B cells, natural killer (NK) cells) and immune escape mechanisms (regulatory T cells (Tregs), macrophages). RT enhances immune responses through DNA release, type I interferons, and immune cell recruitment. Radiation-hypoxic microenvironment affects metabolism and molecular changes. RT-induced hypoxia causes vascular changes, fibrosis, and vessel compression, leading to tissue hypoxia. Hypoxia activates hypoxia-inducible factor (HIF)-1α/2α, promoting angiogenesis and glycolysis in tumor cells. TME changes due to hypoxia also involve immune suppressive cells like myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages (TAMs), and Tregs. The radiation microenvironment is involved in radiation resistance and holds a significant effect on the prognosis of patients with NPC. Exploring the radiation microenvironment provides new insights into RT and NPC research.

14.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 40(5): 843-851, 2023 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-37879912

RESUMO

In order to fully explore the neural oscillatory coupling characteristics of patients with mild cognitive impairment (MCI), this paper analyzed and compared the strength of the coupling characteristics for 28 MCI patients and 21 normal subjects under six different-frequency combinations. The results showed that the difference in the global phase synchronization index of cross-frequency coupling under δ-θ rhythm combination was statistically significant in the MCI group compared with the normal control group ( P = 0.025, d = 0.398). To further validate this coupling feature, this paper proposed an optimized convolutional neural network model that incorporated a time-frequency data enhancement module and batch normalization layers to prevent overfitting while enhancing the robustness of the model. Based on this optimized model, with the phase locking value matrix of δ-θ rhythm combination as the single input feature, the diagnostic accuracy of MCI patients was (95.49 ± 4.15)%, sensitivity and specificity were (93.71 ± 7.21)% and (97.50 ± 5.34)%, respectively. The results showed that the characteristics of the phase locking value matrix under the combination of δ-θ rhythms can adequately reflect the cognitive status of MCI patients, which is helpful to assist the diagnosis of MCI.


Assuntos
Disfunção Cognitiva , Eletroencefalografia , Humanos , Eletroencefalografia/métodos , Disfunção Cognitiva/diagnóstico , Redes Neurais de Computação , Sensibilidade e Especificidade
15.
Org Lett ; 25(40): 7428-7433, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37791679

RESUMO

A B(C6F5)3-catalyzed controllable inter/intra-/intermolecular Si-C bond formation process has been developed from trihydrosilane and dienamide with alkenes, anilines, or aryl iodides. A variety of 1,4-azasilinanes have been generated with diverse exo-cyclic heteroleptic disubstitutions on silicon, thereby expanding the range of silaazacyclic rings available for the discovery of silicon-containing drugs.

16.
Mol Cell Endocrinol ; 578: 112076, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37769867

RESUMO

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder affecting women of reproductive age and is a significant cause of female subfertility. Our previous research demonstrated that the abnormal palmitoylation of heat shock protein-90α (HSP90α) plays a role in the development of PCOS. However, the palmitoyl acyltransferases in HSP90α palmitoylation remain poorly understood. Herein, we identified ZDHHC17 as a major palmitoyl acyltransferase for HSP90α palmitoylation in granulosa cells. ZDHHC17 protein expression was diminished under excess androgen conditions in vitro and in vivo. Consistently, ovarian ZDHHC17 expression was found to be attenuated in patients with PCOS. ZDHHC17 depletion decreased HSP90α palmitoylation levels and hampered the conversion of androgen to estrogen via CYP19A1. Furthermore, ZDHHC17-mediated regulation of CYP19A1 expression was dependent on HSP90α palmitoylation. Our findings reveal that the regulatory role of HSP90α palmitoylation by ZDHHC17 is critical in PCOS pathophysiology and provide insights into the role of ZDHHC17 in reproductive endocrinology.

17.
Reprod Biomed Online ; 47(4): 103238, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37573751

RESUMO

RESEARCH QUESTION: Is early embryo development in mice influenced by RNA binding protein with multiple splicing 2 (RBPMS2), a maternal factor that accumulates and is stored in the cytoplasm of mature oocytes? DESIGN: The expression patterns of RBPMS2 in mouse were analysed using quantitative real-time PCR (qRT PCR) and immunofluorescence staining. The effect of knockdown of RBPMS2 on embryo development was evaluated through a microinjection of specific morpholino or small interfering RNA. RNA sequencing was performed for mechanistic analysis. The interaction between RBPMS2 and the bone morphogenetic protein (BMP) pathway was studied using BMP inhibitor and activator. The effect on the localization of E-cadherin was determined by immunofluorescence staining. RESULTS: Maternal protein RBPMS2 is highly expressed in mouse oocytes, and knockdown of RBPMS2 inhibits embryo development from the morula to the blastocyst stage. Mechanistically, RNA sequencing showed that the differentially expressed genes were enriched in the transforming growth factor-ß (TGF-ß) signalling pathway. BMPs are members of the TGF-ß superfamily of growth factors. It was found that the addition of BMP inhibitor to the culture medium led to a morula-stage arrest, similar to that seen in RBPMS2 knockdown embryos. This morula-stage arrest defect caused by RBPMS2 knockdown was partially rescued by BMP activator. Furthermore, the localization of E-cadherin to the membrane was impaired in response to a knockdown of RBPMS2 or inhibition of the BMP pathway. CONCLUSION: This study suggests that RBPMS2 activates the BMP pathway and thus influences the localization of E-cadherin, which is important for early mouse embryo development during blastocyst formation.


Assuntos
Proteínas Morfogenéticas Ósseas , Desenvolvimento Embrionário , Animais , Camundongos , Blastocisto/metabolismo , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Desenvolvimento Embrionário/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Fator de Crescimento Transformador beta/metabolismo
18.
Materials (Basel) ; 16(15)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37569945

RESUMO

Cold spray (CS) is an emerging technology for repairing and 3D additive manufacturing of a variety of metallic components using deformable metal powders. In CS deposition, gas type, gas pressure, gas temperature, and powder feed rate are the four key process parameters that have been intensively studied. Spray angle, spray gun traverse speed, and standoff distance (SoD) are the other three process parameters that have been less investigated but are also important, especially when depositing on uneven substrates or building up 3D freeform structures. Herein, the effects of spray angle, traverse speed, and SoD during CS deposition have been investigated holistically on a single material system (i.e., Al2219 powders on Al2219-T6 substrate). The coatings' mass gain, thickness, porosity, and residual stress have been characterized, and the results show that spray angle and traverse speed exercise much more effects than SoD in determining coatings' buildup. Finite element method (FEM) modeling and computational fluid dynamic (CFD) simulation have been carried out to understand the effects of these three parameters for implementing CS as repairing and additive manufacturing using aluminum-based alloy powders.

19.
Nanomaterials (Basel) ; 13(14)2023 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-37513045

RESUMO

A series of long-afterglow luminescent materials (SrAl2O4: Eu2+ (SAOE), SrAl2O4: Eu2+, Dy3+ (SAOED) and SrAl2O4: Eu2+, Dy3+, Gd3+ (SAOEDG)) was synthesized via the combustion method. Temperature and concentration control experiments were conducted on these materials to determine the optimal reaction temperature and ion doping concentration for each sample. The crystal structure and luminescent properties were analyzed via X-ray diffraction (XRD), photoluminescence (PL), and afterglow attenuation curves. The outcomes demonstrate that the kind of crystal structure and the location of the emission peak were unaffected by the addition of ions. The addition of Eu2+ to the matrix's lattice caused a broad green emission with a central wavelength of 508 nm, which was attributed to the characteristic 4f65d1 to 4f7 electronic dipole, which allowed the transition of Eu2+ ions. While acting as sensitizers, Dy3+ and Gd3+ could produce holes to create a trap energy level, which served as an electron trap center to catch some of the electrons produced by the excitation of Eu2+ but did not itself emit light. After excitation ceased, this allowed them to gently transition to the ground state to produce long-afterglow luminescence. It was observed that with the addition of sensitizer ions, the luminous intensity of the sample increased, and the afterglow duration lengthened. The elemental structure and valence states of the doped ions were determined with an X-ray photoelectron spectrometer (XPS). Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were used to characterize the samples. The results show that the sample was synthesized successfully, and the type and content of ions in the fluorescent powder could be determined. The fluorescence lifetime, quantum yield, bandgap value, afterglow decay time, and coordinate position in the coherent infrared energy (CIE) diagram of the three best sample groups were then analyzed and compared. Combining the prepared phosphor with ink provides a new idea and method for the field of anti-counterfeiting through screen printing.

20.
Chemosphere ; 338: 139533, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37459932

RESUMO

Urban greenspace (UGS) is recognized to confer significant societal benefits, but few studies explored the microbial communities and antibiotic resistance genes (ARGs) from different urban greenspace types. Here, we collected leaf and soil samples from forest, greenbelt, and parkland to analyze microbial community assembly and ARG profile. For phyllosphere fungal community, the α-diversity was higher in forest, compared to those in greenbelt and parkland. Moreover, urban greenspace types altered the community assembly. Stochastic processes had a greater effect on phyllosphere fungal community in greenbelt and parkland, while in forest they were dominated by deterministic processes. In contrast, no significant differences in bacterial community diversity, community assembly were observed between the samples collected from different urban greenspace types. A total of 153 ARGs and mobile genetic elements (MGEs) were detected in phyllosphere and soil with resistance to the majority classes of antibiotics commonly applied to humans and animals. Structural equation model further revealed that a direct association between greenspace type and ARGs in the phyllosphere even after considering the effects of all other factors simultaneously. Our findings provide new insights into the microbial communities and antibiotic resistome of urban greenspaces and the potential risk linked with human health.


Assuntos
Antibacterianos , Microbiota , Animais , Humanos , Antibacterianos/farmacologia , Solo/química , Genes Bacterianos , Parques Recreativos , Microbiologia do Solo
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