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1.
Brain Lang ; 256: 105458, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39197357

RESUMO

This study investigated the causal enhancing effect of transcranial photobiomodulation (tPBM) over the left inferior frontal gyrus (LIFG) on syntactically complex Mandarin Chinese first language (L1) and second language (L2) sentence processing performances. Two (L1 and L2) groups of participants (thirty per group) were recruited to receive the double-blind, sham-controlled tPBM intervention via LIFG, followed by the sentence processing, the verbal working memory (WM), and the visual WM tasks. Results revealed a consistent pattern for both groups: (a) tPBM enhanced sentence processing performance but not verbal WM for linear processing of unstructured sequences and visual WM performances; (b) Participants with lower sentence processing performances under sham tPBM benefited more from active tPBM. Taken together, the current study substantiated that tPBM enhanced L1 and L2 sentence processing, and would serve as a promising and cost-effective noninvasive brain stimulation (NIBS) tool for future applications on upregulating the human language faculty.


Assuntos
Memória de Curto Prazo , Humanos , Masculino , Feminino , Adulto Jovem , Memória de Curto Prazo/fisiologia , Idioma , Adulto , Método Duplo-Cego , Terapia com Luz de Baixa Intensidade/métodos , Córtex Pré-Frontal/fisiologia , Lobo Frontal/fisiologia , Multilinguismo
2.
Pharmaceutics ; 16(8)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39204317

RESUMO

Cancer remains a highly lethal disease globally. The approach centered on REDOX-targeted mitochondrial therapy for cancer has displayed notable benefits. Plant polyphenols exhibit strong REDOX and anticancer properties, particularly by affecting mitochondrial function, yet their structural instability and low bioavailability hinder their utility. To overcome this challenge, researchers have utilized the inherent physical and chemical characteristics of polyphenols and their derivatives to develop innovative nanomedicines for targeting mitochondria. This review examines the construction strategies and anticancer properties of various types of polyphenol-based biological nanomedicine for regulating mitochondria in recent years, such as polyphenol self-assembly, metal-phenol network, polyphenol-protein, polyphenol-hydrogel, polyphenol-chitosan, and polyphenol-liposome. These polyphenolic nanomedicines incorporate enhanced features such as improved solubility, efficient photothermal conversion capability, regulation of mitochondrial homeostasis, and ion adsorption through diverse construction strategies. The focus is on how these polyphenol nanomedicines promote ROS production and their mechanism of targeting mitochondria to inhibit cancer. Furthermore, it delves into the benefits and applications of polyphenolic nanomedicine in cancer treatments, as well as the challenges for future research.

3.
Int J Biol Macromol ; 274(Pt 2): 133451, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38944088

RESUMO

SARS-CoV-2 main protease (Mpro) is a well-recognized target for COVID-19 therapy. Green tea (-)-epigallocatechin-3-gallate (EGCG) possesses Mpro-inhibitory activity; however, the influence of EGCG oxidation on its inhibition activity remains obscure, given its high oxidation propensity. This study reveals that prolonged EGCG oxidation in the presence of Mpro dramatically increases its inhibitory activity with an IC50 of 0.26 µM. The inhibitory mechanism is that EGCG-quinone preferentially binds the active site Mpro-Cys145-SH, which forms a quinoprotein. Though Mpro is present in the cell lysate, EGCG preferentially depletes its thiols. Non-cytotoxic EGCG effectively generates a quinoprotein in living cells, thus EGCG might selectively inhibit Mpro in SARS-CoV-2 infected cells. Chlorogenic acid facilitates EGCG oxidation. Together, they synergistically deplete multiple Mpro thiols though this is not more beneficial than EGCG alone. By contrast, excessive EGCG oxidation prior to incubation with Mpro largely compromises its inhibitory activity. Overall, the low IC50 and the high selectivity imply that EGCG is a promising dietary Mpro inhibitor. While EGCG oxidation in the presence of Mpro has a pivotal role in inhibition, enhancing EGCG oxidation by chlorogenic acid no longer increases its inhibitory potential. EGCG oxidation in the absence of Mpro should be avoided to maximize its Mpro-inhibitory activity.


Assuntos
Catequina , Proteases 3C de Coronavírus , Oxirredução , SARS-CoV-2 , Catequina/análogos & derivados , Catequina/farmacologia , Catequina/química , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/enzimologia , Humanos , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/metabolismo , Proteases 3C de Coronavírus/química , Ácido Clorogênico/farmacologia , Ácido Clorogênico/química , Ácido Clorogênico/análogos & derivados , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Antivirais/farmacologia , Antivirais/química , Tratamento Farmacológico da COVID-19 , COVID-19/virologia , Domínio Catalítico
4.
Food Funct ; 15(4): 2181-2196, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38315103

RESUMO

(-)-Epigallocatechin-3-gallate (EGCG) is a major polyphenol in tea and exerts several health-promoting effects. It easily autoxidizes into complex polymers and becomes deactivated due to the presence of multiple phenolic hydroxyl structures. Nonetheless, the morphology and biological activity of complex EGCG polymers are yet to be clarified. The present study demonstrated that EGCG autoxidation self-assembled nanoparticles (ENPs) exhibit antioxidant activity in vitro and hepatic REDOX homeostasis regulation activity in vivo. Also, the formation of ENPs during the EGCG autoxidation process was based on the intermolecular interaction forces that maintain the stability of the nanoparticles. Similar to EGCG, ENPs are scavengers of reactive oxygen species and hydroxyl radicals in vitro and also regulate hepatic REDOX activity through liver redox enzymes, including thioredoxin reductase (TrxR), thioredoxin (Trx), glutathione reductase (GR), glutaredoxin (Grx), and glutathione S-transferase (GST) in vivo. Moreover, ENPs activate the NRF2 antioxidant-responsive element pathway, exerting a detoxification effect at high doses. Unlike EGCG, ENPs do not cause liver damage at low doses and also maintain liver biosafety at high doses through self-assembly, forming large particles, which is supported by the unchanged levels of liver damage biomarkers, including serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), liver γ-phosphorylated histone 2AX (γ-H2AX), and P53-related genes (Thbs, MDM2, P53, and Bax). Collectively, these findings revealed that ENPs, with adequate biosafety and regulation of hepatic redox activity in vivo, may serve as substitutes with significant potential for antioxidant applications or as food additives to overcome the instability and liver toxicity of EGCG.


Assuntos
Catequina , Catequina/análogos & derivados , Nanopartículas , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Fígado/metabolismo , Oxirredução , Catequina/farmacologia , Catequina/metabolismo , Polímeros/farmacologia
5.
Food Funct ; 15(4): 2052-2063, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38293823

RESUMO

Green tea polyphenol (-)-Epigallocatechin-3-gallate (EGCG) has been well studied for its biological activities in the prevention of chronic diseases. However, the biological activities of EGCG oxidation-derived polymers remain unclear. Previously, we found that these polymers accumulated in intraperitoneal tissues after intraperitoneal injection and gained an advantage over native EGCG in increasing insulin sensitivity via regulating the renin-angiotensin system (RAS) in type 2 diabetic mice. The present study determined the pro-apoptosis activities and anticancer mechanisms of the EGCG oxidation-derived polymer preparation (the >10 kDa EGCG polymers) in digestive tract cancer cells. Upon incubation of the >10 kDa EGCG polymers with CaCo2 colon cancer cells, these polymers coated the cell surface and regulated multiple components of the RAS in favor of cancer inhibition, including the downregulation of angiotensin-converting enzyme (ACE), angiotensin-II (AngII) and AngII receptor type 1 (AT1R) in the pro-tumor axis, as well as the upregulation of angiotensin-converting enzyme 2 (ACE2) and angiotensin1-7 (Ang(1-7)) in the anti-tumor axis. The treatment also markedly increased angiotensinogen (AGT), which is the precursor of the angiotensin peptides. The regulation of these RAS components occurred prior to apoptosis. Similar pro-apoptotic mechanisms of the >10 kDa EGCG polymers, were also observed in TCA8113 oral cancer cells. The >10 kDa EGCG polymers exhibited compromised activities in scavenging or initiating reactive oxygen species compared to EGCG, but gained a higher reactivity toward sulfhydryl groups, including protein cysteine thiols. We propose that the polymers bind onto the cell surface and regulate multiple RAS components by reacting with the sulfhydryl groups on the ectodomains of transmembrane proteins.


Assuntos
Catequina/análogos & derivados , Diabetes Mellitus Experimental , Neoplasias , Humanos , Camundongos , Animais , Sistema Renina-Angiotensina , Células CACO-2 , Angiotensina II/farmacologia , Apoptose , Trato Gastrointestinal
6.
Food Res Int ; 173(Pt 2): 113482, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803805

RESUMO

Chlorogenic acid (CGA) and caffeic acid (CA) are two major phenolic acids in coffee. Though the International Agency for Research on Cancer has classified CA as a Group2B carcinogen, coffee consumption seems generally safe within the usual levels of intake and is more likely to benefit health than to harm it. We thus speculated that CGA may effectively suppress the carcinogenic potential of CA. In a molar ratio achievable in vivo, this study shows that CGA can inhibit (i) copper reduction caused by CA, (ii) CA oxidation caused by copper, (iii) the formation of hydroxyl radicals by CA and copper, and (iv) DNA damage induced by CA, quercetin or (-)-epigallocatechin-3-gallate in the presence of copper. CA tends to undergo autoxidation to produce hydrogen peroxide and quinone, which further reacts with proteins to form quinoproteins. This autoxidation at a tolerable level normally induces beneficial adaptive responses. This study shows that CGA is less efficient than CA in producing hydrogen peroxide and quinoprotein; however, together they synergistically produce hydrogen peroxide and quinoprotein in vitro at a molar ratio achievable in vivo. In conclusion, CGA can selectively regulate the prooxidant activities of CA depending on whether copper is involved or not. CGA could be viewed as an indispensable partner of CA in coffee, given its dual role in suppressing the carcinogenic potential of CA and boosting CA autoxidation which is beneficial for disease prevention.


Assuntos
Ácido Clorogênico , Café , Café/metabolismo , Ácido Clorogênico/análise , Peróxido de Hidrogênio , Cobre , Ácidos Cafeicos/análise
7.
J Agric Food Chem ; 71(37): 13633-13644, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37671478

RESUMO

Both ammonium sulfite slurry (ASS) from ammonia-based desulfurization and lignite are waste materials with low value. In this work, an innovative method was developed by applying ASS in lignite activation to produce water-soluble humic substances (WHSs) with a high bioactivity and economic value. The optimal activation method was to mix lignite and ASS at a 4:1-liquid-solid ratio by vortex blender and then oscillate it for 30 min at 25 °C. Compared with that of the unactivated lignite (UAL), the yield of WHSs from activated lignite (AL) increased by 42.72%. WHSs from AL consisted of a large number of aliphatic carbons with low molecular weight and functional groups such as amides, amines, sulfonic acid groups, C-O, and so forth. Moreover, WHSs from AL at lower concentrations (2 mg/L) has a more obvious root-elongation-promoting effect than WHSs from UAL (10 mg/L). Activation experiment with the lignite-related model compounds revealed that ASS caused the breakage of Caliph-O, Caliph-Caliph, and Carom-Caliph linkages between aromatic rings. These findings provide a theoretical basis for the development of green and sustainable technologies for the beneficial reuse of ASS and lignite in agriculture.


Assuntos
Amônia , Substâncias Húmicas , Agricultura , Água
8.
Front Psychol ; 14: 1143062, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37151349

RESUMO

Introduction: A hallmark of the human language faculty is processing complex hierarchical syntactic structures across languages. However, for Mandarin Chinese, a language typically dependent on semantic combinations and free of morphosyntactic information, the relationship between syntactic and semantic processing during Chinese complex sentence reading is unclear. From the neuropsychological perspective of bilingual studies, whether second language (L2) learners can develop a consistent pattern of target language (i.e., L2) comprehension regarding the interplay of syntactic and semantic processing, especially when their first language (L1) and L2 are typologically distinct, remains to be determined. In this study, Chinese complex sentences with center-embedded relative clauses were generated. By utilizing the high-time-resolution technique of event-related potentials (ERPs), this study aimed to investigate the processing relationships between syntactic and semantic information during Chinese complex sentence reading in both Chinese L1 speakers and highly proficient L2 learners from South Korea. Methods: Normal, semantically violated (SEM), and double-violated (containing both semantic and syntactic violations, SEM + SYN) conditions were set with regard to the nonadjacent dependencies of the Chinese complex sentence, and participants were required to judge whether the sentences they read were acceptable. Results: The ERP results showed that sentences with "SEM + SYN" did not elicit early left anterior negativity (ELAN), a component assumed to signal initial syntactic processing, but evoked larger components in the N400 and P600 windows than those of the "SEM" condition, thus exhibiting a biphasic waveform pattern consistent for both groups and in line with previous studies using simpler Chinese syntactic structures. The only difference between the L1 and L2 groups was that L2 learners presented later latencies of the corresponding ERP components. Discussion: Taken together, these results do not support the temporal and functional priorities of syntactic processing as identified in morphologically rich languages (e.g., German) and converge on the notion that even for Chinese complex sentence reading, syntactic and semantic processing are highly interactive. This is consistent across L1 speakers and high-proficiency L2 learners with typologically different language backgrounds.

9.
J Virol ; 97(5): e0177022, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37129496

RESUMO

Vimentin (VIM), an indispensable protein, is responsible for the formation of intermediate filament structures within cells and plays a crucial role in viral infections. However, the precise role of VIM in classical swine fever virus (CSFV) infection remains unclear. Herein, we systematically investigated the function of VIM in CSFV replication. We demonstrated that both knockdown and overexpression of VIM affected CSFV replication. Furthermore, we observed by confocal microscopy the rearrangement of cellular VIM into a cage-like structure during CSFV infection. Three-dimensional (3D) imaging indicated that the cage-like structures were localized in the endoplasmic reticulum (ER) and ringed around the double-stranded RNA (dsRNA), thereby suggesting that VIM was associated with the formation of the viral replication complex (VRC). Mechanistically, phosphorylation of VIM at serine 72 (Ser72), regulated by the RhoA/ROCK signaling pathway, induced VIM rearrangement upon CSFV infection. Confocal microscopy and coimmunoprecipitation assays revealed that VIM colocalized and interacted with CSFV NS5A. Structurally, it was determined that amino acids 96 to 407 of VIM and amino acids 251 to 416 of NS5A were the respective important domains for this interaction. Importantly, both VIM knockdown and disruption of VIM rearrangement inhibited the localization of NS5A in the ER, implying that VIM rearrangement recruited NS5A to the ER for VRC formation. Collectively, our results suggest that VIM recruits NS5A to form a stable VRC that is protected by the cage-like structure formed by VIM rearrangement, ultimately leading to enhanced virus replication. These findings highlight the critical role of VIM in the formation and stabilization of VRC, which provides alternative strategies for the development of antiviral drugs. IMPORTANCE Classical swine fever (CSF), caused by classical swine fever virus (CSFV), is a highly infectious disease that poses a significant threat to the global pig industry. Therefore, gaining insights into the virus and its interaction with host cells is crucial for developing effective antiviral measures and controlling the spread of CSF. Previous studies have shown that CSFV infection induces rearrangement of the endoplasmic reticulum, leading to the formation of small vesicular organelles containing nonstructural protein and double-stranded RNA of CSFV, as well as some host factors. These organelles then assemble into viral replication complexes (VRCs). In this study, we have discovered that VIM recruited CSFV NS5A to form a stable VRC that was protected by a cage-like structure formed by rearranged VIM. This enhanced viral replication. Our findings not only shed light on the molecular mechanism of CSFV replication but also offer new insights into the development of antiviral strategies for controlling CSFV.


Assuntos
Vírus da Febre Suína Clássica , Peste Suína Clássica , Suínos , Animais , Vírus da Febre Suína Clássica/fisiologia , Vimentina/metabolismo , RNA de Cadeia Dupla , Filamentos Intermediários/metabolismo , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Replicação Viral , Antivirais , Aminoácidos/genética
10.
Colloids Surf B Biointerfaces ; 226: 113329, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37156027

RESUMO

Diethyldithiocarbamate-copper complex (CuET) shows promising anticancer effect; nonetheless, preclinical evaluations of CuET are hindered due to poor solubility. We prepared bovine serum albumin (BSA)-dispersed CuET nanoparticles (CuET-NPs) to overcome the shortcoming. Results from a cell-free redox system demonstrated that CuET-NPs reacted with glutathione, leading to form hydroxyl radical. Glutathione-mediated production of hydroxyl radicals may help explain why CuET selectively kills drug-resistant cancer cells with higher levels of glutathione. CuET-NPs dispersed by autoxidation products of green tea epigallocatechin gallate (EGCG) also reacted with glutathione; however, the autoxidation products eradicated hydroxyl radicals; consequently, such CuET-NPs exhibited largely compromised cytotoxicity, suggesting that hydroxyl radical is a crucial mediator of CuET anticancer activity. In cancer cells, BSA-dispersed CuET-NPs exhibited cytotoxic activities equivalent to CuET and induced protein poly-ubiquitination. Moreover, the reported powerful inhibition of CuET on colony formation and migration of cancer cells could be replicated by CuET-NPs. These similarities demonstrate BSA-dispersed CuET-NPs is identical to CuET. Thus, we advanced to pilot toxicological and pharmacological evaluations. CuET-NPs caused hematologic toxicities in mice and induced protein poly-ubiquitination and apoptosis of cancer cells inoculated in mice at a defined pharmacological dose. Given high interest in CuET and its poor solubility, BSA-dispersed CuET-NPs pave the way for preclinical evaluations.


Assuntos
Antineoplásicos , Nanopartículas , Animais , Camundongos , Soroalbumina Bovina , Radical Hidroxila , Portadores de Fármacos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral
11.
ACS Omega ; 8(11): 9775-9784, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36969453

RESUMO

Controlled-release fertilizers (CRFs) could improve crop yield and fertilizer use efficiency. However, the coating materials of conventional CRFs are mainly derived from petrochemical products, which are expensive and nondegradable, bringing potential environmental pollution. Therefore, using sustainable bio-based materials is the development direction. In this study, large tablet urea (LTU) was prepared using physical extrusion technology. The economical and biodegradable liquefied apple tree branch bio-based coating material was used to coat LTU, obtaining large tablet CRFs (LTCRUs). Also, the optimum proportion of liquefaction of apple tree branches modified by castor oil was studied. The specific surface area, surface morphology, and FTIR of LTCRU were characterized. The results showed that the surface of the LTCRU was the most smooth and the LTCRU modified with 30% castor oil presented the best controlled-release characteristics. The specific surface area of LTCRU was one-third of that of traditional small-particle fertilizers, which indicated that reducing the using dosage of coating materials is economical. Overall, this work provided theoretical and technical supports for the industrialization of biocoated superlarge tablet urea, which is conducive to the green development of agriculture.

12.
PLoS One ; 18(3): e0282471, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36897845

RESUMO

Accurate PM2.5 prediction is part of the fight against air pollution that helps governments to manage environmental policy. Satellite Remote sensing aerosol optical depth (AOD) processed by The Multi-Angle Implementation of Atmospheric Correlation (MAIAC) algorithm allows us to observe the transportation of remote pollutants between regions. The paper proposes a composite neural network model, the Remote Transported Pollutants (RTP) model, for such long-range pollutant transportation that predicts more accurate local PM2.5 concentrations given such satellite data. The proposed RTP model integrates several deep learning components and learns from the heterogeneous features of various domains. We also detected remote transportation pollution events (RTPEs) at two reference sites from the AOD data. Extensive experiments using real-world data show that the proposed RTP model outperforms the base model that does not account for RTPEs by 17%-30%, 23%-26% and 18%-22% and state-of-the-art models that account for RTPEs by 12%-22%, 12%-14%, and 10%-11% at +4h to +24h, +28h to +48 hours, and +52h to +72h hours respectively.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Material Particulado/análise , Taiwan , Monitoramento Ambiental , Poluição do Ar/análise , Aerossóis/análise
13.
Redox Biol ; 51: 102259, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35168078

RESUMO

The present study investigated the influence of epigallocatechin-3-gallate (EGCG) and its autoxidation products on insulin sensitivity in db/db mice. Compared to EGCG, autoxidation products of EGCG alleviated diabetic symptoms by suppressing the deleterious renal axis of the renin-angiotensin system (RAS), activating the beneficial hepatic axis of RAS, and downregulating hepatic and renal SELENOP and TXNIP. A molecular weight fraction study demonstrated that polymeric oxidation products were of essential importance. The mechanism of action involved coating polymeric oxidation products on the cell surface to protect against cholesterol loading, which induces abnormal RAS. Moreover, polymeric oxidation products could regulate RAS and SELENOP at doses that were far below cytotoxicity. The proof-of-principal demonstrations of EGCG-derived polymeric oxidation products open a new avenue for discovering highly active polymeric oxidation products based on the oxidation of naturally occurring polyphenols to manage diabetes and other diseases involving abnormal RAS.


Assuntos
Catequina , Diabetes Mellitus , Resistência à Insulina , Animais , Catequina/análogos & derivados , Catequina/farmacologia , Diabetes Mellitus/metabolismo , Rim/metabolismo , Camundongos , Oxirredução
14.
Front Psychiatry ; 12: 729930, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721106

RESUMO

Background: With the control of the epidemic, adolescents' mental outlook might have improved. However, little evidence existed with regard to the psychological status of adolescents in post-COVID-19 era. This present study aimed to explore the psychological status of high school students after the epidemic getting eased. Methods: A web-based cross-sectional survey was used to obtain data from three high schools, including the demographic information, the Patient Health Questionnaire-9 (PHQ-9), the Generalized Anxiety Disorder-7 (GAD-7), the Self-Rating Scale of Sleep (SRSS), and self-designed general recent-status questionnaire. Correlation analysis was performed to explore potential associations between the depression symptoms, anxiety symptoms, and sleep status. The PHQ-9 and GAD-7 differences between nowadays data and the data enrolled 12 months before were also compared. Result: A total of 1,108 qualified questionnaires were obtained. The prevalence of depressive and anxious symptoms was 27.5 and 21.3%, respectively, from mild to severe in all students, while 11.8% of these high students got sleep disturbances. Both the rate and the severity of depression, anxiety and sleep problems of female students were higher than male students. Grade three students suffered higher prevalence and severer mental disturbances than the other two grades. There were significant correlations between the depression symptoms, anxiety symptoms, and sleep status. The psychological status has been improved in nowadays high school students compared with the sample enrolled 12 months before. Conclusion: As a supplement to our former study, this present research provided a perspective on the psychological status of high school students 1 year after the COVID-19 pandemic being well controlled. We should pay attention to the psychological status of high school students, and should also notice the progresses made by this special group after the epidemic.

15.
Sensors (Basel) ; 21(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201901

RESUMO

In this paper, we investigated the performance of a two-way satellite-terrestrial DF relay network with asymmetric simultaneous wireless information and power transfer (SWIPT). In particular, selective physical-layer network coding (SPNC) was employed in the proposed network, improving the throughput performance. We derived the expressions of system average end-to-end throughput and single node detection (SND) occurrence probability. Furthermore, to observe the effects of the power splitting (PS) coefficient on the energy efficiency performance, the expressions of energy harvested in the physical-layer network coding (PNC) and SPNC protocol were also derived. Finally, theoretical analyses and Monte Carlo simulation results are presented to show: (i) SPNC protocol outperforms the conventional PNC protocol in the two-way satellite-terrestrial relay network with SWIPT in infrequent light shadowing (ILS), average shadowing (AS), and frequent heavy shadowing (FHS) Shadowed-Rician fading channels; (ii) as the channel state gets worse, SPNC protocol can achieve more performance improvement than PNC protocol; (iii) as the PS coefficient increases, the average end-to-end throughput performance increases progressively, and the average energy efficiency performance increases progressively within a certain range, while decreasing in the others.


Assuntos
Redes de Comunicação de Computadores , Tecnologia sem Fio , Algoritmos , Simulação por Computador , Probabilidade
16.
Front Psychiatry ; 11: 570096, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33408653

RESUMO

Background: The coronavirus disease 2019 (covid-19) has brought physical risks as well as psychological challenges to the whole world. High school students are a special group suffering from both the academic pressure and the threat of the epidemic. The present study aims to conduct an online survey to investigate the psychological status of high school students in Shandong Province. Methods: Using a web-based cross-sectional survey, data was collected from 1,018 voluntary high school students assessed with demographic information, the Patient Health Questionnaire-9 (PHQ-9), the Generalized Anxiety Disorder-7 (GAD-7) and a self-designed online-study effect survey. Correlation analysis was performed to explore the relationships between depression symptoms, anxiety symptoms, and study effect. Result: The prevalence of depressive symptoms, anxiety symptoms, and a combination of depressive and anxiety symptoms was 52.4, 31.4, and 26.8%, respectively, among high school students in Shandong Province during the COVID-19 epidemic. And from moderate to severe severity level, the rates of depressive symptoms and anxious symptoms were 17.6 and 4.6%. Female students exhibited a higher rate and severity of mental symptoms than male, and grade one senior high school students got a higher rate and severity of mental symptoms than the other two grades. Nearly half of the students were not satisfied with their online-study effect. The PHQ-9 score had a strong positive correlation with the GAD-7 score. Both the PHQ-9 score the GAD-7 score had a negative correlation with the study-effect survey score. Conclusion: Quite a number of high school students suffered from depression and anxiety symptoms during the COVID-19 epidemic. Sufficient attentions should be paid, and necessary supports should be provided, to protect the mental health of this special group.

17.
Int J Pediatr Otorhinolaryngol ; 77(10): 1734-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24012220

RESUMO

OBJECTIVES: To establish a hearing screening program with high coverage, low referral rate, high follow-up rate, and early intervention in Taipei City. METHODS: From September 2009 to December 2010, 85% delivery units in Taipei City, which includes 20 hospitals and 14 obstetrics clinics, were recruited into the screening program in two stages. A total of 15,930 babies were born in these participating hospitals and clinics during the program period. Among these neonates, 15,790 underwent hearing screening test with automatic auditory brainstem response (AABR). The screening was free of charge to the parents. The hearing screening examination was performed 24-36 h after birth. The same test was repeated between 36 and 60 h of age if the baby failed the first hearing test. The neonate was referred to the diagnostic hospitals for further investigations if he failed the second test. RESULTS: The screening coverage rate was 99.1% (15,790/15,930). The incidence of bilateral moderate to severe and unilateral hearing loss was 1.4 per 1000 (22/15,790) and 1.5 per 1000 (24/15,790), respectively. Four percent (626/15,790) of newborns failed to pass the initial screening test and 1.0% of newborns failed to pass the second screening test. Therefore, 1.0% newborns were referred for diagnostic assessments. The follow-up rate was 94.4% (151/160). Sixty-four percent (14/22) of babies with bilateral hearing loss completed the full diagnostic hearing tests within 3 months of birth. CONCLUSIONS: The universal newborn hearing screening program is an adequate program for Taipei City with high coverage, low referral rate, and good follow-up rate. Screening fees covered by third parties, two-stage screening steps with AABR strategy, and the stringent monitoring system proved to be effective. LEVEL OF EVIDENCE: 2b, individual cohort study.


Assuntos
Transtornos da Audição/congênito , Transtornos da Audição/epidemiologia , Triagem Neonatal/organização & administração , Surdez/diagnóstico , Surdez/epidemiologia , Países em Desenvolvimento , Feminino , Transtornos da Audição/diagnóstico , Perda Auditiva Bilateral/congênito , Perda Auditiva Bilateral/diagnóstico , Perda Auditiva Bilateral/epidemiologia , Perda Auditiva Neurossensorial/congênito , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/epidemiologia , Perda Auditiva Unilateral/congênito , Perda Auditiva Unilateral/diagnóstico , Perda Auditiva Unilateral/epidemiologia , Testes Auditivos/métodos , Testes Auditivos/estatística & dados numéricos , Humanos , Recém-Nascido , Masculino , Programas de Rastreamento/organização & administração , Prevalência , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Taiwan/epidemiologia
18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 74(1 Pt 2): 016601, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16907198

RESUMO

Optical vortices are shown to be generated in the near-field through interference between a propagating wave and the amplified evanescent field in a slab of lossy left-handed material. While small loss adversely impacts the sub-wavelength performance in the lens application, the vortex character shown relies on some degree of imperfection. These vortices can be controlled by means of gain/loss and the incident field.

19.
Opt Lett ; 30(18): 2382-4, 2005 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16196326

RESUMO

A power analysis of the lossy negative refractive index or left-handed slab lens is described. The presence of vortices in the image plane is revealed with small loss or gain, and these are attributed to the influence of field growth in the evanescent spectrum.

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