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1.
Opt Express ; 32(10): 18247-18256, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38858986

RESUMEN

As a novel optical device, the plasmonic random laser has unique working principle and emission characteristics. However, the simultaneous enhancement of absorption and emission by plasmons is still a problem. In this paper, we propose a broad-band-enhanced plasmonic random laser. Two-dimensional silver (Ag) nanostar arrays were prepared using a bottom-up method with the assistance of self-assembled nanosphere templates. The plasmon resonance of Ag nanostars contributes to the pump light absorption and photoluminescence (PL) of RhB. Coherent random lasing was achieved in RhB@PVA film based on localized surface plasmon resonance (SPR) dual enhancement and scattering feedback of Ag nanostars. Ag nanostars prepared with different nanosphere diameters affect the laser emission wavelength. In addition, the random laser device achieves wavelength tunability on a flexible substrate under mechanical external force.

2.
PLoS One ; 19(6): e0305594, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38885267

RESUMEN

Urban agglomerations (UAs), which serve as pivotal hubs for economic and innovative convergence, play a crucial role in enhancing internal circulation and strengthening external linkages. This study utilizes the China city-level multi-regional input-output tables, incorporating the Dagum Gini coefficient and kernel density estimation methods, to perform a thorough quantitative analysis. Disparities within the national and global value chains ("dual value chains") of Chinese UAs from 2012 to 2017 were assessed. Additionally, the logarithmic mean Divisia index (LMDI) method was applied to disaggregate the drivers of both national and global intermediate inputs (NII and GII). The study's key findings include the following: (1) The national value chain (NVC) within UAs exhibits robust growth, contrasting with the decline in the global value chain (GVC). (2) The inter-UA disparity contribution rate significantly surpasses the combined rates of intra-UA contribution and super-variation density. (3) Distinct evolutionary peak trends are discerned among various UAs within the "dual value chains", highlighting diverse spatial polarization characteristics and expansiveness. (4) The growth of the NVC has transitioned from a negative to a positive impact on NII, while the decline in GVC has substantially counteracted GII growth. Economic and demographic factors notably drive positive improvements in both NII and GII, whereas the efficiency of outflows presents a negative driving effect. Based on these findings, this study offers strategic recommendations to facilitate the effective integration of UAs into the new development paradigm, thereby providing a scientific basis for related decision-making processes.


Asunto(s)
Ciudades , China , Humanos , Urbanización/tendencias , Desarrollo Económico/tendencias
3.
Front Psychol ; 15: 1305609, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38420166

RESUMEN

Introduction: In recent years, growing concern has emerged regarding the mental health and well-being of college students who confront numerous challenges and transitions during their higher education journey. This research aims to investigate the influence of positive childhood experiences on the adaptability of college students and the underlying mechanisms. Methods: A cross-sectional survey was conducted with 5,787 college students from Chinese universities. Participants completed an online questionnaire assessing positive childhood experiences, self-esteem, the number of siblings, and China college students' adjustment. Results: The results revealed that positive childhood experiences positively predicted the adjustment of China college students, with self-esteem playing a mediating role in this positive effect. Moreover, siblings played an antagonistic moderating role in the positive effect of positive childhood experiences on China college students' adjustment. Discussion: It is recommended to enhance positive childhood experiences, improve self-esteem, and provide additional care and support to students from multi-sibling families to enhance China college students' adjustment.

4.
Heliyon ; 10(9): e30345, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38711669

RESUMEN

In this study, the sodium dodecyl sulfate intercalated modified magnesium-aluminum hydrotalcite/sodium alginate/sodium carboxymethylcellulose (modified LDHs/SA/CMC) composite gel spheres were synthesized and their efficacies in adsorbing the cationic dye rhodamine B (RhB) from aqueous solutions were evaluated. The effects of adsorption time, pH and temperature on the adsorption of RhB by spheres were investigated. Remarkably, the modified LDHs/SA/CMC gel spheres achieved adsorption equilibrium after 600 min at 25 °C, and the removal rate of RhB at 60 mg/L reached 91.49 % with the maximum adsorption capacity of 59.64 mg/g. The gel spheres maintained over 80 % efficacy across four adsorption cycles. Kinetic and isotherm analyses revealed that the adsorption of RhB conformed to the secondary kinetic model and the Langmuir isotherm, indicating a spontaneous and exothermic nature of the adsorption process. The adsorption mechanisms of modified LDHs/SA/CMC gel spheres on RhB dyes include electrostatic adsorption, hydrogen bonding and hydrophobic interactions. In conclusion, modified LDHs/SA/CMC gel sphere is a green, simple, recyclable and efficient adsorbent, which is expected to be widely used for the treatment of cationic dye wastewater.

5.
Medicine (Baltimore) ; 100(4): e23873, 2021 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-33530181

RESUMEN

BACKGROUND: Ischemic stroke is a huge threat to human health globally. Rescuing neurons in the ischemic penumbra (IP) is pivotal after the onset of ischemic stroke, and autophagy is essential to the survival of IP neurons and the development of related pathological processes. As the most common autophagy inhibitor, 3-Methyladenine (3-MA) is widely used in studies related to the mechanism of neuronal autophagy in ischemic stroke; however, there is no consensus has been reached on its effects of neuroprotection or neurodamage, which hinders the development and clinical application of autophagy-targeted therapy strategies for the treatment of ischemic stroke. METHODS: We will search the following electronic bibliographic databases: PubMed, EMBASE, Scopus, Science Direct, and Web of Science. Participant intervention comparator outcomes of this study are as flowing: P, animal models of ischemic stroke; I, received 3-MA treatment merely; C, received only vehicle or sham treatment, or no treatment; O, Primary outcomes are infarct volume; neuro-behavioral scores. Secondary outcomes are cerebral blood flow, blood-brain barrier permeability, cerebral hemorrhage, brain water content. Review Manager 5.3 and Stata 15.1 will be used in data analysis. The characteristics of the studies, the experimental model, and the main results will be described, the quality assessment and the risk of bias assessment will be conducted. A narrative synthesis will be made for the included studies. Besides, if sufficient qualitative data is available, a meta-analysis will be conducted. I2 statistics will be used to assess heterogeneity. DISCUSSION: This systematic review and meta-analysis of the autophagy inhibitor 3-MAs effects on animal models of ischemic stroke can help us to understand whether inhibiting autophagy brings protection or damage to IP neurons; in addition, it also helps to clarify the specific role of autophagy in cerebral infarction. Therefore, this study can provide evidence for the future development of therapy strategies targeting autophagy and bring more hope to patients with ischemic stroke. PROSPERO REGISTRATION NUMBER: CRD42020194262.


Asunto(s)
Adenina/análogos & derivados , Autofagia/efectos de los fármacos , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Metaanálisis como Asunto , Revisiones Sistemáticas como Asunto , Adenina/uso terapéutico , Animales , Infarto Encefálico/tratamiento farmacológico , Infarto Encefálico/patología , Infarto Encefálico/fisiopatología , Protocolos Clínicos , Accidente Cerebrovascular Isquémico/patología , Accidente Cerebrovascular Isquémico/fisiopatología , Modelos Animales , Neuronas/patología , Proyectos de Investigación
6.
Zhen Ci Yan Jiu ; 46(9): 751-6, 2021 Sep 25.
Artículo en Zh | MEDLINE | ID: mdl-34558240

RESUMEN

OBJECTIVE: To observe the effect of acupuncture on the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and endostatin (Endostatin, ES) mRNAs and proteins (angiogenesis related factors) in the ischemic penumbra region in rats with cerebral infarction (CI), so as to explore its underlying mechanisms in prolonging the time window of thrombolysis therapy for CI. METHODS: A total of 48 male SD rats were randomly divided into sham operation, model, medication (6 h thrombolysis) and acupuncture (Acupunct)+medication groups (n=12 in each group). The CI model was established using modified auto-thrombus method. Six hours after thrombolysis, recombinant human tissue plasminogen activator (rt-PA,10 mg/kg) was given to rats of the thrombolysis group through tail vein. Acupuncture was applied at "Shuigou"(CV26) and bilateral "Neiguan" (PC6) 2 h after successful modeling, and the needles were retained for 30 minutes. Cerebral blood flow (CBF) was monitored during modeling in each group, and the neurological deficit score (0-7 points) was given 2 h and 24 h after successful modeling according to Bederson's methods. The cerebral infarction volume was observed after triphenyltetrazole chloride (TTC) staining. The protein and mRNA expression levels of VEGF, bFGF and ES in the ischemic penumbra region of the right cerebral cortex were detected by Western blot and real-time PCR, separately. RESULTS: The neurological deficit score at both 2 h and 24 h after modeling, percentage of cerebral infarction volume, and the expression levels of VEGF, bFGF and ES proteins and mRNAs in the model group were significantly higher than those of the sham operation group (P<0.01, P < 0.05). Compared with the model group, the neurological deficit score 24 h (not at 2 h) after modeling and percentage of cerebral infarction volume, and the expression levels of ES protein and mRNA in the Acupunct+medication group (not in the medication group) were notably lower (P<0.05, P<0.01), while the expression levels of VEGF and bFGF proteins and mRNAs in the Acupunct +medication group (not in the medication group) were considerably higher (P<0.01, P<0.05). No significant differences were found between medication and model groups in the CI percentage, VEGF, bFGF and ES proteins and mRNAs (P>0.05). The therapeutic effect of Acupunct +medication group was significantly superior to that of medication in lowering neurological deficit score, percentage of CI volume and expression of ES protein and mRNA and in up-regulating the expression of VEGF and bFGF proteins and mRNAs (P<0.05, P<0.01). CONCLUSION: Acupuncture and timely intervention can prolong the time window of thrombolysis in CI rats, which may be related to its function in up-regulating the expression of VEGF and bFGF mRNAs and proteins and in down-regulating the expression of ES mRNA and protein in ischemic cerebral cortex.


Asunto(s)
Terapia por Acupuntura , Isquemia Encefálica , Animales , Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Corteza Cerebral , Infarto Cerebral/genética , Infarto Cerebral/terapia , Masculino , Ratas , Ratas Sprague-Dawley , Terapia Trombolítica , Activador de Tejido Plasminógeno , Factor A de Crecimiento Endotelial Vascular/genética
7.
Environ Sci Pollut Res Int ; 21(18): 10890-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24770927

RESUMEN

Water in the Yangtze Estuary is fresh most of the year because of the large discharge of Yangtze River. The Qingcaosha Reservoir built on the Changxing Island in the Yangtze Estuary is an estuarine reservoir for drinking water. Denitrification rate in the top 10 cm sediment of the intertidal marshes and bare mudflat of Yangtze Estuarine islands was measured by the acetylene inhibition method. Annual denitrification rate in the top 10 cm of sediment was 23.1 µmol m(-2) h(-1) in marshes (ranged from 7.5 to 42.1 µmol m(-2) h(-1)) and 15.1 µmol m(-2) h(-1) at the mudflat (ranged from 6.6 to 26.5 µmol m(-2) h(-1)). Annual average denitrification rate is higher at mashes than at mudflat, but without a significant difference (p = 0.084, paired t test.). Taking into account the vegetation and water area of the reservoir, a total 1.42 × 10(8) g N could be converted into nitrogen gas (N2) annually by the sediment, which is 97.7 % of the dissolved inorganic nitrogen input through precipitation. Denitrification in reservoir sediment can control the bioavailable nitrogen level of the water body. At the Yangtze estuary, denitrification primarily took place in the top 4 cm of sediment, and there was no significant spatial or temporal variation of denitrification during the year at the marshes and mudflat, which led to no single factor determining the denitrification process but the combined effects of the environmental factors, hydrologic condition, and wetland vegetation.


Asunto(s)
Desnitrificación , Agua Potable , Sedimentos Geológicos/química , Compuestos de Nitrógeno/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Abastecimiento de Agua , China , Monitoreo del Ambiente/métodos , Estuarios
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