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1.
Ecotoxicol Environ Saf ; 277: 116384, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38657451

RESUMO

It's of great challenge to address for heavy metal-contaminated soil. Once the farmland is contaminated with heavy metals, the microbial ecology of the plant rhizosphere will change, which in turn impacts crop productivity and quality. However, few studies have explored the effects of heavy metals on plant rhizosphere microbes in farmland and the role that plant cultivation plays in such a phytoremediation practice. In this study, the impacts of comfrey (Symphytum officinale L.) cultivation and the stresses of cadmium/zinc (Cd/Zn) on rhizosphere soil microflora were examined. Microbial DNA was collected from soils to evaluate the prevalence of bacteria and fungi communities in rhizosphere soils. High-throughput 16 S rRNA sequencing was used to determine the diversity of the bacterial and fungal communities. The results showed that growing comfrey on polluted soils reduced the levels of Cd and Zn from the vertical profile. Both the comfrey growth and Cd/Zn stresses affected the community of rhizosphere microorganisms (bacteria or fungi). Additionally, the analysis of PCoA and NMDS indicated that the cultivation of comfrey significantly changed the bacterial composition and structure of unpolluted soil. Comfrey cultivation in polluted and unpolluted soils did not result in much variance in the fungi's species composition, but the fungal compositions of the two-type soils were noticeably different. This work provided a better understanding of the impacts of Cd/Zn stresses and comfrey cultivation on rhizosphere microbial community, as well as new insight into phytoremediation of heavy metal-contaminated soils.


Assuntos
Bactérias , Biodegradação Ambiental , Cádmio , Fungos , Rizosfera , Microbiologia do Solo , Poluentes do Solo , Zinco , Cádmio/toxicidade , Zinco/toxicidade , Poluentes do Solo/toxicidade , Fungos/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Bactérias/genética , Solo/química , Microbiota/efeitos dos fármacos , Metais Pesados/toxicidade , Estresse Fisiológico
2.
Sensors (Basel) ; 24(11)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38894412

RESUMO

Surface roughness is one of the main bases for measuring the surface quality of machined parts. A large amount of training data can effectively improve model prediction accuracy. However, obtaining a large and complete surface roughness sample dataset during the ultra-precision machining process is a challenging task. In this article, a novel virtual sample generation scheme (PSOVSGBLS) for surface roughness is designed to address the small sample problem in ultra-precision machining, which utilizes a particle swarm optimization algorithm combined with a broad learning system to generate virtual samples, enriching the diversity of samples by filling the information gaps between the original small samples. Finally, a set of ultra-precision micro-groove cutting experiments was carried out to verify the feasibility of the proposed virtual sample generation scheme, and the results show that the prediction error of the surface roughness prediction model was significantly reduced after adding virtual samples.

3.
Small ; 19(27): e2300194, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36965012

RESUMO

Versatile electrocatalysis at higher current densities for natural seawater splitting to produce hydrogen demands active and robust catalysts to overcome the severe chloride corrosion, competing chlorine evolution, and catalyst poisoning. Hereto, the core-shell-structured heterostructures composed of amorphous NiFe hydroxide layer capped Ni3 S2 nanopyramids which are directly grown on nickel foam skeleton (NiS@LDH/NF) are rationally prepared to regulate cooperatively electronic structure and mass transport for boosting oxygen evolution reaction (OER) performance at larger current densities. The prepared NiS@LDH/NF delivers the anodic current density of 1000 mA cm-2 at the overpotential of 341 mV in 1.0 m KOH seawater. The feasible surface reconstruction of Ni3 S2 -FeNi LDH interfaces improves the chemical stability and corrosion resistance, ensuring the robust electrocatalytic activity in seawater electrolytes for continuous and stable oxygen evolution without any hypochlorite production. Meanwhile, the designed Ni3 S2 nanopyramids coated with FeNi2 P layer (NiS@FeNiP/NF) still exhibit the improved hydrogen evolution reaction (HER) activity in 1.0 m KOH seawater. Furthermore, the NiS@FeNiP/NF||NiS@LDH/NF pair requires cell voltage of 1.636 V to attain 100 mA cm-2 with a 100% Faradaic efficiency, exhibiting tremendous potential for hydrogen production from seawater.

4.
Nucleic Acids Res ; 49(7): 3764-3780, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33675668

RESUMO

Molecular bases of eukaryotic circadian clocks mainly rely on transcriptional-translational feedback loops (TTFLs), while epigenetic codes also play critical roles in fine-tuning circadian rhythms. However, unlike histone modification codes that play extensive and well-known roles in the regulation of circadian clocks, whether DNA methylation (5mC) can affect the circadian clock, and the associated underlying molecular mechanisms, remains largely unexplored in many organisms. Here we demonstrate that global genome DNA hypomethylation can significantly lengthen the circadian period of Arabidopsis. Transcriptomic and genetic evidence demonstrate that SUPPRESSOR OF drm1 drm2 cmt3 (SDC), encoding an F-box containing protein, is required for the DNA hypomethylation-tuned circadian clock. Moreover, SDC can physically interact with another F-box containing protein ZEITLUPE (ZTL) to diminish its accumulation. Genetic analysis further revealed that ZTL and its substrate TIMING OF CAB EXPRESSION 1 (TOC1) likely act downstream of DNA methyltransferases to control circadian rhythm. Together, our findings support the notion that DNA methylation is important to maintain proper circadian pace in Arabidopsis, and further established that SDC links DNA hypomethylation with a proteolytic cascade to assist in tuning the circadian clock.


Assuntos
Proteínas de Arabidopsis/metabolismo , Metilação de DNA , DNA de Plantas/química , Proteínas F-Box/metabolismo , Arabidopsis , Relógios Circadianos , Ritmo Circadiano , Fatores de Transcrição/metabolismo
5.
Int J Mol Sci ; 23(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36555288

RESUMO

The forkhead box O (FOXO) transcription factors (TFs) family are frequently mutated, deleted, or amplified in various human cancers, making them attractive candidates for therapy. However, their roles in pan-cancer remain unclear. Here, we evaluated the expression, prognostic value, mutation, methylation, and clinical features of four FOXO family genes (FOXO1, FOXO3, FOXO4, and FOXO6) in 33 types of cancers based on the Cancer Genome Atlas (TCGA) and Genotype Tissue Expression (GTEx) databases. We used a single sample gene set enrichment analysis (ssGSEA) algorithm to establish a novel index called "FOXOs score". Moreover, we investigated the association between the FOXOs score and tumor microenvironment (TME), the responses to multiple treatments, along with drug resistance. We found that the FOXO family genes participated in tumor progression and were related to the prognosis in various types of cancer. We calculated the FOXOs score and found that it was significantly correlated with multiple malignant pathways in pan-cancer, including Wnt/beta-catenin signaling, TGF-beta signaling, and hedgehog signaling. In addition, the FOXOs score was also associated with multiple immune-related characteristics. Furthermore, the FOXOs score was sensitive for predicting the efficacy of diverse treatments in multiple cancers, especially immunotherapy. In conclusion, FOXO family genes were vital in pan-cancer and were strongly correlated with the TME. A high FOXOs score indicated an excellent immune-activated TME and sensitivity to multiple treatments. Hence, the FOXOs score might potentially be used as a biomarker in patients with a tumor.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Fatores de Transcrição Forkhead , Multiômica , Neoplasias , Humanos , Fatores de Transcrição Forkhead/genética , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , Microambiente Tumoral
6.
Molecules ; 27(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36432201

RESUMO

Molecules with donor-spacer-acceptor configuration have been developed rapidly given their peculiar properties. How to utilize intermolecular interactions and charge transfers for solution-processed organic light-emitting diodes (OLEDs) greatly relies on molecular design strategy. Herein, soluble luminophores with D-spacer-A motif were constructed via shortening the alkyl chain from nonane to propane, where the alkyl chain was utilized as a spatial linker between the donor and acceptor. The alkyl chain blocks the molecular conjugation and induces the existence of aggregation-induced intermolecular CT emission, as well as the improved solubility and morphology in a solid-state film. In addition, the length of the alkyl chain affects the glass transition temperature, carrier transport and balance properties. The mCP-3C-TRZ with nonane as the spacer shows better thermal stability and bipolar carrier transport ability, so the corresponding solution-processable phosphorescent organic light-emitting diodes exhibit superior external quantum efficiency of 9.8% when using mCP-3C-TRZ as a host material. This work offers a promising strategy to establish a bipolar host via utilizing intermolecular charge transfer process in an aggregated state.

7.
Small ; 17(38): e2101856, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34390182

RESUMO

Developing cost-efficient multifunctional electrocatalysts is highly critical for the integrated electrochemical energy-conversion systems such as water electrolysis based on hydrogen/oxygen evolution reactions (HER/OER) and metal-air batteries based on OER/oxygen reduction reactions (ORR). The core-shell structured materials with transition metal phosphide as the core and nitrogen-doped carbon (NC) as the shell have been known as promising HER electrocatalysts. However, their oxygen-related electrocatalytic activities still remain unsatisfactory, which severely limits their further applications. Herein an effective strategy to improve the core and shell performances of core-shell Co2 P@NC electrocatalysts through secondary metal (e.g., Fe, Ni, Mo, Al, Mn) doping (termed M-Co2 P@M-N-C) is reported. The as-synthesized M-Co2 P@M-N-C electrocatalysts show multifunctional HER/OER/ORR activities and good integrated capabilities for overall water splitting and Zn-air batteries. Among the M-Co2 P@M-N-C catalysts, Fe-Co2 P@Fe-N-C electrocatalyst exhibits the best catalytic activities, which is closely related to the configuration of highly active species (Fe-doping Co2 P core and Fe-N-C shell) and their subtle synergy, and a stable carbon shell for outstanding durability. Combination of electrochemical-based in situ Fourier transform infrared spectroscopy with extensive experimental investigation provides deep insights into the origin of the activity and the underlying electrocatalytic mechanisms at the molecular level.

8.
Nucleic Acids Res ; 47(10): 5001-5015, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-30892623

RESUMO

Circadian clock coordinates numerous plant growth and developmental processes including cell elongation in the hypocotyl, whether or not it modulates cell proliferation is largely unknown. Here we have found that Pseudo Response Regulators (PRRs), essential components of circadian core oscillators, affect root meristem cell proliferation mediated by Target Of Rapamycin (TOR) signaling. The null mutants of PRRs display much reduced sensitivities to sugar-activated TOR signaling. We have subsequently identified Tandem Zinc Finger 1, encoding a processing body localized RNA-binding protein, as a direct target repressed by PRRs in mediating TOR signaling. Multiple lines of biochemical and genetic evidence have demonstrated that TZF1 acts downstream of PRRs to attenuate TOR signaling. Furthermore, TZF1 could directly bind TOR mRNA via its tandem zinc finger motif to affect TOR mRNA stability. Our findings support a notion that PRR-TZF1-TOR molecular axis modulates root meristem cell proliferation by integrating both transcriptional and post-transcriptional regulatory mechanisms.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Proliferação de Células/genética , Fosfatidilinositol 3-Quinases/genética , Raízes de Plantas/genética , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Arabidopsis/citologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Relógios Circadianos , Regulação da Expressão Gênica de Plantas , Meristema/citologia , Meristema/genética , Meristema/metabolismo , Mutação , Fosfatidilinositol 3-Quinases/metabolismo , Raízes de Plantas/citologia , Raízes de Plantas/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais/genética , Fatores de Transcrição/metabolismo
9.
Cancer Control ; 27(1): 1073274820976667, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33356518

RESUMO

Breast-conserving therapy was once a contraindication in young breast cancer patients (aged ≤40 years). Emerging studies suggest that breast-conserving therapy and mastectomy could achieve similar prognosis in this population. However, the effect of molecular subtype disparity on surgical strategy in these patients remains unclear. Data from 8656 young patients (aged ≤40 years) diagnosed with invasive breast cancer between in 2010 and 2014 were retrospectively reviewed from the Surveillance, Epidemiology, and End Results database. The Cox proportional hazards model was used to evaluate subtype-dependent relationships between the surgical method and survival. Of the 8656 patients, 4132 (47.7%) underwent breast-conserving therapy and 4524 (52.3%) underwent mastectomy. The median follow-up period was 30.0 months. Patients in the breast-conserving therapy group demonstrated better overall survival and breast cancer-specific survival than those in the mastectomy group (both p < 0.05). Patients with different molecular subtypes exhibited significant differences in overall survival and breast cancer-specific survival (p < 0.001). Patients with luminal subtypes experienced better overall survival and breast cancer-specific survival than those with the triple-negative subtype. Multivariate analysis revealed that overall mortality risk of the breast-conserving therapy group was lower than that of the mastectomy group among HR(+)HER-2(-) and HR(-)HER-2(-) patients (overall mortality risk of 36.3% [adjusted hazard ratio = 0.637 {95% confidence interval = 0.448-0.905}, p = 0.012] and 36.0% [adjusted hazard ratio = 0.640 {95% confidence interval = 0.455-0.901}, p = 0.010] respectively.) The breast cancer-specific mortality risk was also lower by a percentage similar to that of the overall mortality risk. In the HR(+)HER-2(+) group, the surgical method was an independent prognostic factor for breast cancer-specific survival (adjusted hazard ratio = 0.275 [95% confidence interval = 0.089-0.849], p = 0.025), while there was a trend that patients with breast-conserving therapy had better overall survival than those with mastectomy (p = 0.056). In the HR(-)HER-2(+) group, no significant difference was observed in overall survival and breast cancer-specific survival (p = 0.791 and p = 0.262, respectively). Breast-conserving therapy resulted in significantly better prognosis in patients with luminal and triple-negative subtypes, while no significant difference was observed in patients with the HER-2 enriched subtype. These results may be helpful in informing clinically precise decision-making for surgery in this population.


Assuntos
Neoplasias da Mama/cirurgia , Mama/patologia , Mastectomia Radical/estatística & dados numéricos , Mastectomia Segmentar/estatística & dados numéricos , Recidiva Local de Neoplasia/epidemiologia , Adolescente , Adulto , Fatores Etários , Mama/cirurgia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Tomada de Decisão Clínica , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/prevenção & controle , Estadiamento de Neoplasias , Prognóstico , Receptor ErbB-2/análise , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/análise , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/análise , Receptores de Progesterona/metabolismo , Estudos Retrospectivos , Programa de SEER/estatística & dados numéricos , Adulto Jovem
10.
Proc Natl Acad Sci U S A ; 111(2): 652-7, 2014 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-24374628

RESUMO

We report on crystal structures of ternary Thermus thermophilus Argonaute (TtAgo) complexes with 5'-phosphorylated guide DNA and a series of DNA targets. These ternary complex structures of cleavage-incompatible, cleavage-compatible, and postcleavage states solved at improved resolution up to 2.2 Å have provided molecular insights into the orchestrated positioning of catalytic residues, a pair of Mg(2+) cations, and the putative water nucleophile positioned for in-line attack on the cleavable phosphate for TtAgo-mediated target cleavage by a RNase H-type mechanism. In addition, these ternary complex structures have provided insights into protein and DNA conformational changes that facilitate transition between cleavage-incompatible and cleavage-compatible states, including the role of a Glu finger in generating a cleavage-competent catalytic Asp-Glu-Asp-Asp tetrad. Following cleavage, the seed segment forms a stable duplex with the complementary segment of the target strand.


Assuntos
Proteínas Argonautas/química , DNA Bacteriano/química , Modelos Moleculares , Conformação Proteica , Thermus thermophilus/química , Proteínas Argonautas/metabolismo , Catálise , DNA Bacteriano/metabolismo , Thermus thermophilus/metabolismo
11.
J Phys Condens Matter ; 36(34)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38640920

RESUMO

Gallium arsenide (GaAs) materials have the advantages of high electron mobility, electron saturation drift rate, and other irreplaceable semiconducting properties. They play an important role in the electronics, solar and other fields. However, during GaAs film sedimentary growth, As atoms can undergo segregation to formAs8clusters because of the influence of external factors, which affect the surface morphology and internal structure of these films. In this study, a series of investigations on the deposition and growth of GaAs crystal films were performed. Additionally, the deposition and growth of GaAs thin films were simulated using molecular dynamics. The influence of As8clusters on the surface morphology and internal structure of GaAs films at different incidence angles, velocities and substrate temperatures was studied by using 'defect analysis technology' and 'diamond structure identification' in open source software, along with surface roughness and radial distribution function. Results show that with increasing incident angle, the number ofAs8clusters decreases and film density increases. Increasing incident velocity increases the irregular movement ofAs8clusters in air, and their deposition on the film surface affects the morphology of the film, and the surface roughness increases first and then decreases. Additionally, we investigated the effect of different substrate temperatures on the film surface. Results show that at a substrate temperature of 1173 K, the number ofAs8clusters in the film decreases or the As8clusters disappear, heterogeneous nucleation occurs in the film, and the crystallization rate increases. Although the dislocation line associated with nucleation may affect the mechanical and optical properties of the film, it considerably reduces the annealing effort after the deposition and growth.

12.
Mar Environ Res ; 196: 106398, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38377938

RESUMO

NH3-N and NO2-N always co-exist in the aquatic environment, but there is not a clear opinion on their joint toxicities to the molluscs. Presently, clams Ruditapes philippinarum were challenged by environmental concentrations of NH3-N and NO2-N, singly or in combination, and analyzed by metabolomics approaches, enzyme assays and transmission electron microscope (TEM) observation. Results showed that some same KEGG pathways with different enriched-metabolites were detected in the three exposed groups within one day, and completely different profiles of metabolites were found in the rest of the exposure period. The combined exposure induced heavier and more lasting toxicities to the clams compared with their single exposure. ACP activity and the number of secondary lysosomes were significantly increased after the combined exposure. The present study shed light on the joint-toxicity mechanism of NH3-N and NO2-N, and provided fundamental data for the toxicity research on inorganic nitrogen.


Assuntos
Bivalves , Poluentes Químicos da Água , Animais , Nitritos/toxicidade , Nitritos/metabolismo , Amônia/toxicidade , Amônia/metabolismo , Dióxido de Nitrogênio/metabolismo , Bivalves/metabolismo , Estresse Oxidativo , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/metabolismo
13.
Small Methods ; : e2400108, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558249

RESUMO

In contrast to the thermodynamically unfavorable anodic oxygen evolution reaction, the electrocatalytic urea oxidation reaction (UOR) presents a more favorable thermodynamic potential. However, the practical application of UOR has been hindered by sluggish kinetics. In this study, hierarchical porous nanosheet arrays featuring abundant Ni-WO3 heterointerfaces on nickel foam (Ni-WO3/NF) is introduced as a monolith electrode, demonstrating exceptional activity and stability toward UOR. The Ni-WO3/NF catalyst exhibits unprecedentedly rapid UOR kinetics (200 mA cm-2 at 1.384 V vs. RHE) and a high turnover frequency (0.456 s-1), surpassing most previously reported Ni-based catalysts, with negligible activity decay observed during a durability test lasting 150 h. Ex situ X-ray photoelectron spectroscopy and density functional theory calculations elucidate that the WO3 interface significantly modulates the local charge distribution of Ni species, facilitating the generation of Ni3+ with optimal affinity for interacting with urea molecules and CO2 intermediates at heterointerfaces during UOR. This mechanism accelerates the interfacial electrocatalytic kinetics. Additionally, in situ Fourier transform infrared spectroscopy provides deep insights into the substantial contribution of interfacial Ni-WO3 sites to UOR electrocatalysis, unraveling the underlying molecular-level mechanisms. Finally, the study explores the application of a direct urea fuel cell to inspire future practical implementations.

14.
Cell Death Discov ; 10(1): 7, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182573

RESUMO

Breast cancer is the second leading cause of death in women worldwide, with triple-negative breast cancer (TNBC) having the worst prognosis. Although there are numerous studies on TNBC, there is no effective treatment for it, and it is still a major problem today. Studies on PIWI-interacting RNAs (piRNAs) are increasing and investigating the mechanism of piRNAs in the proliferation and metastasis of TNBC may lead to new potential treatment targets. Here, we identified a novel piRNA, piR-YBX1, which was downregulated in TNBC compared to matched normal breast tissue. Overexpression of piR-YBX1 significantly inhibited the proliferation, migration, invasion ability of TNBC cells both in vivo and in vitro. Mechanistically, piR-YBX1 could bind directly to mRNA of Y-box binding protein 1 (YBX1) and overexpression of piR-YBX1 downregulated YBX1 in both mRNA and protein levels, while the function of piR-YBX1 could be partly rescued by overexpression of YBX1. In addition, YBX1 could bind to RAF1 which is the key molecule in the MAPK signaling pathway, and overexpression of piR-YBX1 inhibited the p-MEK and p-ERK1/2, which can be reverted by YBX1. In conclusion, our findings discovered that the piR-YBX1/YBX1/MAPK axis suppresses the proliferation and metastasis of TNBC and therefore piR-YBX1 has the potential to be an effective therapeutic agent for breast cancer.

15.
J Adv Res ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960276

RESUMO

INTRODUCTION: Growing interest toward RNA modification in cancer has inspired the exploration of datasets related to multiple RNA modifications. However, a comprehensive elucidation of the clinical value of various RNA modifications in breast cancer is still lacking. OBJECTIVES: This study aimed to provide a strategy based on RNA modification-related genes for predicting therapy response and survival outcomes in breast cancer patients. METHODS: Genes related to thirteen RNA modification patterns were integrated for establishing a nine-gene-containing signature-RMscore. Alterations of tumor immune microenvironment and therapy response featured by different RMscore levels were assessed by bulk transcriptome, single-cell transcriptome and genomics analyses. The biological function of key RMscore-related molecules was investigated by cellular experiments in vitro and in vivo, using flow cytometry, immunohistochemistry and immunofluorescence staining. RESULTS: This study has raised an effective therapy strategy for breast cancer patients after a well-rounded investigation of RNA modification-related genes. With a great performance of predicting patient prognosis, high levels of the RMscore proposed in this study represented suppressive immune microenvironment and therapy resistance, including adjuvant chemotherapy and PD-L1 blockade treatment. As the key contributor of the RMscore, inhibition of WDR4 impaired breast cancer progression significantly in vitro and in vivo, as well as participated in regulating cell cycle and mTORC1 signaling pathway via m7G modification. CONCLUSION: Briefly, this study has developed promising and effective tactics to achieve the prediction of survival probabilities and treatment response in breast cancer patients.

16.
BMC Psychol ; 12(1): 263, 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38735963

RESUMO

A growing number of studies have reported that problematic social networking use (PSNU) is strongly associated with anxiety symptoms. However, due to the presence of multiple anxiety subtypes, existing research findings on the extent of this association vary widely, leading to a lack of consensus. The current meta-analysis aimed to summarize studies exploring the relationship between PSNU levels and anxiety symptoms, including generalized anxiety, social anxiety, attachment anxiety, and fear of missing out. 209 studies with a total of 172 articles were included in the meta-analysis, involving 252,337 participants from 28 countries. The results showed a moderately positive association between PSNU and generalized anxiety (GA), social anxiety (SA), attachment anxiety (AA), and fear of missing out (FoMO) respectively (GA: r = 0.388, 95% CI [0.362, 0.413]; SA: r = 0.437, 95% CI [0.395, 0.478]; AA: r = 0.345, 95% CI [0.286, 0.402]; FoMO: r = 0.496, 95% CI [0.461, 0.529]), and there were different regulatory factors between PSNU and different anxiety subtypes. This study provides the first comprehensive estimate of the association of PSNU with multiple anxiety subtypes, which vary by time of measurement, region, gender, and measurement tool.


Assuntos
Ansiedade , Rede Social , Humanos , Ansiedade/psicologia , Transtorno de Adição à Internet/psicologia
17.
Nanotechnology ; 24(43): 435704, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24084632

RESUMO

We report the synthesis of a novel compound, 9,9-bis(3'-aminopropyl)-2,7-diphenylfluorene (BAPDPF), and a new approach to graft the BAPDPF onto a CdS quantum dot (QD) surface via an acylation reaction. FT-IR and TGA characterizations indicate the formation of robust bonding between BAPDPF and QDs; the structures of the bare QDs and BAPDPF-CdS QD hybrid nanocomposites estimated by transmission electron microscopy (TEM) showed that they have the same size of about 3.5 nm. The extent of the spectral overlap between the emission of BAPDPF and absorption of QDs, and the change of fluorescence emission for the organic and inorganic components of the hybrid, demonstrate that the energy transfer process occurs from BAPDPF to the CdS QDs. The energy transfer of about 44% efficiency is corroborated by time-resolved fluorescence measurements, and then the solid-state photoluminescence quantum yield (PLQY) of the nanocomposite is measured using an integrating sphere and a conventional fluorimeter. Because of the fact that the PLQY of the nanocomposite is 9.1 times larger than that of the pristine QDs, due to the energy transfer between the donor and the acceptor and passivation effects on the surface of the acceptor, the presented BAPDPF-CdS QD hybrid nanocomposites are potentially interesting in nanoparticle-based light-emitting devices.

18.
Aquat Toxicol ; 261: 106624, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37407303

RESUMO

Ammonia nitrogen is a long-lasting pollutant along the Chinese coast. In our previous studies, the clam Ruditapes philippinarum exhibited several toxic responses to environmental concentrations of ammonia nitrogen. To elucidate the underlying mechanism of ammonia nitrogen toxicity in clams at the post-transcriptional level, microRNA (miRNA) expression profiles were investigated by high-throughput sequencing after the clams were exposed to 0.1 mg/L ammonia nitrogen for 30 days. A total of 238 miRNAs were identified, including 49 conserved miRNAs and 189 novel miRNAs. After comparative analysis, six miRNAs were significantly expressed after 1 day of exposure, with three up-regulated and three down-regulated miRNAs. In addition, 35 miRNAs were significantly expressed after 30 days of exposure, of which 16 were up-regulated and 19 were down-regulated. Furthermore, the target genes of each differentially expressed miRNA were predicted, followed by Gene Ontology (GO) category and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. The target genes were predicted to be involved in the immune response, protein processing and transport, DNA damage repair, cellular communication, neural signaling, redox homeostasis, lipid metabolism, and biotransformation. A biological phagocytosis assay proved the speculation that ammonia nitrogen regulated the immunity of clams with the aid of a novel miRNA (novel_29). These findings support further research on miRNA levels in R. philippinarum exposed to ammonia nitrogen.


Assuntos
Bivalves , MicroRNAs , Poluentes Químicos da Água , Animais , Amônia/toxicidade , Amônia/metabolismo , Nitrogênio/metabolismo , Poluentes Químicos da Água/toxicidade , MicroRNAs/genética , MicroRNAs/metabolismo , Bivalves/metabolismo
19.
Front Psychol ; 14: 1228294, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37637921

RESUMO

Background: With the lifting of Zero-COVID policies in China, rapid transmission of the virus has led to new challenges for patients' health anxiety. This study aimed to evaluate the relationship between COVID-19 symptoms and health anxiety, as well as the mediation paths between them in individuals infected with COVID-19. Method: A cross-sectional study was conducted in December 2022, following the relaxation of anti-COVID measures in China. A validated online questionnaire was used to collect data from COVID-19 patients on the number and severity of symptoms, health anxiety, internet health information-seeking behavior (IHISB), and perceived stigma. Structural equation modeling was used to examine the mediation model in which COVID-19 symptoms would affect health anxiety via IHISB and perceived stigma. Results: Overall, 1,132 participants (women, 67.6%) were included, with a mean (SD) age of 28.12 (10.07) years. Participants had an average of seven COVID-19 symptoms, with cough (91.3%), nasal congestion (89.1%) and fatigue (87.8%) being the most common. The number and severity of COVID-19 symptoms, IHISB, perceived stigma, and health anxiety were positively correlated with each other after adjusting for covariates (r ranging from 0.10 to 0.81, all p < 0.05). IHISB (effect = 0.14, p < 0.001) and perceived stigma (effect = 0.04, p < 0.001) fully mediated the relationship between COVID-19 symptoms and health anxiety. Conclusion: Interventions for health anxiety reduction during and after pandemics should target improving the quality of online health information, enhancing individuals' online healthy literacy, and reducing stigma.

20.
Nanomicro Lett ; 15(1): 155, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37337062

RESUMO

Hydrazine-assisted water electrolysis is a promising energy conversion technology for highly efficient hydrogen production. Rational design of bifunctional electrocatalysts, which can simultaneously accelerate hydrogen evolution reaction (HER)/hydrazine oxidation reaction (HzOR) kinetics, is the key step. Herein, we demonstrate the development of ultrathin P/Fe co-doped NiSe2 nanosheets supported on modified Ni foam (P/Fe-NiSe2) synthesized through a facile electrodeposition process and subsequent heat treatment. Based on electrochemical measurements, characterizations, and density functional theory calculations, a favorable "2 + 2" reaction mechanism with a two-step HER process and a two-step HzOR step was fully proved and the specific effect of P doping on HzOR kinetics was investigated. P/Fe-NiSe2 thus yields an impressive electrocatalytic performance, delivering a high current density of 100 mA cm-2 with potentials of - 168 and 200 mV for HER and HzOR, respectively. Additionally, P/Fe-NiSe2 can work efficiently for hydrazine-assisted water electrolysis and Zn-Hydrazine (Zn-Hz) battery, making it promising for practical application.

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