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1.
Opt Lett ; 49(15): 4393-4396, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090942

RESUMO

Airyprime beams are known for their powerful autofocusing property, which are further enhanced by the introduction of a circular structure-circular Airyprime beam (CAPB). We derive an asymptotic expression of the CAPB in Fourier space (FS) and verify its accuracy by the numerical Fourier transform (FT) method. Through FS modulation on it, adjustable control of autofocusing property of the FS-modulated CAPB can be achieved, whose lower and upper limits can reach 8.7% reduction and 2.6 times enhancement compared to the unmodulated one. The experimental results agree well with the numerical analyses. Our findings offer promising possibilities for efficient particle trapping and enhancing free-space optical communication capabilities.

2.
Opt Lett ; 49(11): 2857-2860, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824276

RESUMO

By designing the intricate coherence structure, we are able to create a desired beam profile and trajectory. Our research focus lies on the Fourier plane, specifically emphasizing the coherence of spatial frequencies, and we find it can be seen as a constant system response. A theoretical framework is developed, and experimental studies are conducted to generate a light field of the spatial spectrum with a complex correlation using the pseudo-mode superposition method. We successfully produce partially coherent Pearcey-Gauss beams whose spatial spectrum is hyperbolic sine correlational. Interestingly, these beams maintain the distinctive propagation properties of the Pearcey pattern while exhibiting the remarkable ability to split the mainlobe into two separate lobes.

3.
Opt Lett ; 49(2): 290-293, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38194550

RESUMO

The group velocity (GV) modulation of space-time wave packets (STWPs) along the transverse and longitudinal directions in free space is constrained by various factors. To surmount this limitation, a technique called "flying focus" has been developed, which enables the generation of laser pulses with dynamic focal points that can propagate at arbitrary velocities independent of GV. In this Letter, we propose a (3+1)-dimensional Pearcey-Gauss wave packet based on the "flying focus" technique, which exhibits superluminal propagation, transverse focus oscillation, and longitudinal periodic autofocusing. By selecting appropriate parameters, we can flexibly manipulate the position, the size, and the number of focal points- or make the wave packet follow a desired trajectory. This work may pave the way for the advancement of space-time structured light fields.

4.
Opt Lett ; 48(13): 3535-3538, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37390174

RESUMO

In this Letter, we present an approach for particle manipulation utilizing twisted circle Pearcey vortex beams. These beams are modulated by a noncanonical spiral phase, which allows for flexible adjustment of rotation characteristics and spiral patterns. Consequently, particles can be rotated around the beam's axis and trapped with a protective barrier to avoid perturbation. Our proposed system can quickly de-gather and re-gather multiple particles, enabling a swift and thorough cleaning of small areas. This innovation opens up new possibilities in particle cleaning and creates a new platform for further study.

5.
Opt Lett ; 48(22): 6004-6007, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37966774

RESUMO

It is a highly significant area of research to investigate how to effectively enhance the focusing ability of abruptly auto-focusing beams (AAFBs) while extending the focal length. We introduce a dual-region parabolic trajectory offset modulation to auto-focusing ring Pearcey beams (RPBs), presenting a novel, to the best of our knowlege, approach to extend the focal length while greatly enhancing their auto-focusing capabilities. Unlike directly introducing a linear chirp, which inevitably shortens the focal length to enhance the auto-focusing ability and allows only single focusing in the RPBs, our scheme can achieve a multi-focusing effect. Furthermore, we have experimentally generated such a beam, verifying our theoretical predictions. Our findings offer promising possibilities for generating optical bottles, trapping multiple particles periodically, and enhancing free-space optical communication capabilities.

6.
J Opt Soc Am A Opt Image Sci Vis ; 40(7): 1392-1396, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37706740

RESUMO

A virtual source (VS) is a hypothetical source instead of an actual physical entity, but provides a distinctive perspective to understand physical fields in a source-free area. In this work, we generalize the VS theory to structured partially coherent light fields (PCLFs) by establishing the partially coherent inhomogeneous Helmholtz equation, then demonstrate that PCLFs can be generated from the incoherent extended VS in imaginary space. Especially, we put forward an understanding of the Gaussian Schell-model beam, which consists of a group of partially coherent paraxial complex rays. The mutual coherence between these rays depends on the included angle between them. In previous studies, the analytical solution of the partially coherent Airy beam was obtained with difficulty by the Huygens-Fresnel integral; however, by applying the VS, we put forward, to our knowledge, an unprecedented analytical solution for a partially coherent Airy beam. We believe this example will qualify the VS as an important perspective to understand structured PCLFs.

7.
Pestic Biochem Physiol ; 197: 105701, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38072556

RESUMO

BACKGROUND: Aluminum phosphide (AlP) is a well-known toxic compound used as an agricultural pesticide to prevent insect damage to stored crops. However, even if just a small amount was consumed, it caused lasting harm to the human body and, in acute concentrations, death. The current study employed cerium oxide nanoparticles (CeO2 NPs) to reduce oxidative stress and various harmful outcomes of AlP poisoning. METHODS: Following finding effective concentrations of CeO2 NPs via MTT assay, Human Cardiac Myocyte (HCM) cells were pre-treated with CeO2 NPs for 24 h. After that, they were exposed to 2.36 µM AlP. The activity of oxidative stress and mitochondrial biomarkers, including mitochondrial swelling, mitochondrial membrane potential, and cytochrome c release, were evaluated in HCM cells. Finally, the population of apoptotic and necrotic cells was assessed via flow cytometry. RESULTS: After 24 h, data revealed that all tested concentrations of CeO2 NPs were safe, and 25 and 50 µM of that were selected as effective concentrations. Oxidative stress markers (malondialdehyde, protein carbonyl, superoxide dismutase, and catalase) showed that CeO2 NPs could successfully decrease AlP poisoning due to their antioxidant characteristics. Mitochondrial markers were also recovered by pre-treatment of HCM cells with CeO2 NPs. Furthermore, pre-treating with CeO2 NPs could compensate for the reduction of live cells with AlP and cause a diminishing in the population of early and late apoptotic cells. CONCLUSION: As a result, it is evident that CeO2 NPs, through the recovery of oxidative stress and mitochondrial damages caused by AlP, reduce apoptosis and have therapeutic potentials on HCM cells.


Assuntos
Nanopartículas , Praguicidas , Humanos , Praguicidas/toxicidade , Estresse Oxidativo
8.
Electrophoresis ; 42(9-10): 1043-1049, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-31087687

RESUMO

Currently, the global healthcare market is increasing at high speed with the impendent global aging issue. Healthcare Industry 4.0 has emerged as an efficient solution towards the aging issue since it was integrated with ubiquitous medical sensors, big health processing platform, high bandwidth, speed technologies, and medical services, etc. It is believed to fulfil the requirement of the tremendously growing health market. The acquisition of medical data acts as the dominant precondition to implement the Healthcare Industry 4.0. In the same way, the widely available smartphone could serve as the best biomedical information collect station. In this study, a smartphone-powered photochemical dongle is demonstrated to precisely estimate blood creatinine from the fingertip blood, which works as a highly compact reflectance spectral analyzer with an enzymatically dry chemical test strip. Comparing with conventional laboratory facility for the evaluation and treatment of chronic kidney disease (CKD), it implemented the platform of point care with agreed accuracy. In order to estimate the efficiency of treatment and recovery of the CKD, the proposed photochemical dongle would provide a flexible and rapid platform for point of care. Furthermore, the proposed measured technology is very promising method for remote CKD management.


Assuntos
Smartphone , Atenção à Saúde , Humanos , Rim/fisiologia , Sistemas Automatizados de Assistência Junto ao Leito , Insuficiência Renal Crônica/terapia
9.
Soc Sci Res ; 99: 102598, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34429211

RESUMO

Political ideology not only influences political activities, but also apolitical fields such as charitable giving. However, empirical studies regarding political ideology and charitable giving have yielded mixed results. To find out the effect size and explain the variation in effect sizes, we deploy a meta-analysis to estimate the average effect size and examine the potential moderators from four perspectives. Following scientific data collection and coding procedures, we identify 421 effect sizes from 31 empirical studies. Our meta-analysis results suggest that political conservatives are significantly more charitable than liberals at an overall level, but the relationship between political ideology and charitable giving varies under different scenarios. Furthermore, meta-regression results indicate that the measure of charitable giving, the type of charitable giving, and controlling for religiosity can account for the variation in effect sizes.


Assuntos
Política , Religião , Humanos
10.
BMC Genomics ; 15: 898, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25318379

RESUMO

BACKGROUND: Stripe rust (Puccinia striiformis f. sp. tritici; Pst) and powdery mildew (Blumeria graminis f. sp. tritici; Bgt) are important diseases of wheat (Triticum aestivum) worldwide. Similar mechanisms and gene transcripts are assumed to be involved in the host defense response because both pathogens are biotrophic fungi. The main objective of our study was to identify co-regulated mRNAs that show a change in expression pattern after inoculation with Pst or Bgt, and to identify mRNAs specific to the fungal stress response. RESULTS: The transcriptome of the hexaploid wheat line N9134 inoculated with the Chinese Pst race CYR 31 was compared with that of the same line inoculated with Bgt race E09 at 1, 2, and 3 days post-inoculation. Infection by Pst and Bgt affected transcription of 23.8% of all T. aestivum genes. Infection by Bgt triggered a more robust alteration in gene expression in N9134 compared with the response to Pst infection. An array of overlapping gene clusters with distinctive expression patterns provided insight into the regulatory differences in the responses to Bgt and Pst infection. The differentially expressed genes were grouped into seven enriched Kyoto Encyclopedia of Genes and Genomes pathways in Bgt-infected leaves and four pathways in Pst-infected leaves, while only two pathways overlapped. In the plant-pathogen interaction pathway, N9134 activated a higher number of genes and pathways in response to Bgt infection than in response to Pst invasion. Genomic analysis revealed that the wheat genome shared some microbial genetic fragments, which were specifically induced in response to Bgt and Pst infection. CONCLUSIONS: Taken together, our findings indicate that the responses of wheat N9134 to infection by Bgt and Pst shows differences in the pathways and genes activated. The mass sequence data for wheat-fungus interaction generated in this study provides a powerful platform for future functional and molecular research on wheat-fungus interactions.


Assuntos
Ascomicetos/fisiologia , Basidiomycota/fisiologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Triticum/microbiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Patógeno , Análise de Sequência com Séries de Oligonucleotídeos , Folhas de Planta/genética , Folhas de Planta/microbiologia , Transdução de Sinais , Triticum/anatomia & histologia , Triticum/genética
11.
Work ; 77(4): 1205-1217, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38007635

RESUMO

BACKGROUND: The tunnel section is a complex traffic scenario and an accident prone area. There are differences in the performance of different driving groups in tunnel environments, which may have an impact on traffic safety. OBJECTIVE: To study the differences in the impact of tunnel environment on professional and non-professional drivers. METHODS: Based on the vehicle experimental data, the electroencephalography (EEG) power was compared for professional and non-professional drivers. The impact of illumination changes and longitudinal slope on different driving groups was analyzed. RESULTS: At tunnel entrance with severely reduced lighting, the adaptation time of non-professional drivers to the light environment is 1.5 times that of professional drivers. When driving on the longitudinal slope, professional drivers perform better. The greater the longitudinal slope, the more obvious the advantages of professional drivers. However, in areas with relatively good traffic conditions, professional drivers are more prone to be distracted. CONCLUSION: Professional and non-professional drivers have their own advantages and disadvantages in the tunnel environment. In general, the driving adaptability of professional drivers is better than that of non-professional drivers in tunnel sections. The research conclusions provide a reference for driver safety training.


Assuntos
Condução de Veículo , Humanos , Acidentes de Trânsito , Iluminação , Eletroencefalografia
12.
Int J Occup Saf Ergon ; : 1-10, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39056265

RESUMO

A tunnel shading shed is crucial in improving driving safety as a type of traffic facility to ease the transition of light environments. To study the effect of installation of a shading shed on the visual characteristics of drivers in the connecting zone of the adjacent tunnels, a total of 32 drivers were gathered to perform a real vehicle experiment. The study zone of the adjacent tunnels was divided into three sections: upstream tunnel exit; connecting zone; and downstream tunnel threshold zone. Fixation duration, saccade duration and saccade frequency were selected as research indexes. The results suggest that installation of a shading shed in the connecting zone significantly reduced the fixation (saccade) duration in the upstream tunnel exit and downstream tunnel threshold zones, with a significantly higher saccade frequency. In addition, fixation is better improved at the downstream tunnel entrance, and saccade is better enhanced at the upstream tunnel exit.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38349396

RESUMO

Myocardial infarction is a worldwide disease with high morbidity and mortality and a major cause of chronic heart failure, seriously affecting patients' quality of life. Natural medicine has been used to cure or prevent cardiovascular disease for decades. As a natural flavonoid, anthocyanidin has been used to treat many diseases due to its antioxidative, anti-inflammatory, and other properties. A mouse model (C57BL/6) weighing 30-40 g was utilized to induce myocardial infarction by ligating the left anterior descending coronary artery. Cyanidin (30 mg/kg) was administered orally to mice for four weeks. A variety of assessments were used to evaluate cardiac function. The gene expression was measured using RNAseq and Western blot. Histological changes in myocardial tissue were assessed using staining techniques, including Masson, Hematoxylin Eosin (HE), and transmission electron microscopy. Tunnel staining was implemented as a method to detect cellular apoptosis. For the quantification of B-type natriuretic peptide (BNP) and atrial natriuretic peptide (ANP) in the serum, an enzyme-linked immunosorbent assay (ELISA) was employed. Furthermore, autodock simulation was executed in order to assess the interaction between cyanidin and a subset of genes. Cyanidin treatment inhibited myocardial cell apoptosis, improved cardiac function, and reduced serum concentrations of BNP and atrial natriuretic peptide ANP, as well as mitigated histological cardiac tissue damage. Cyanidin also inhibited the activity of matrix metalloproteinases (MMP2/9) and Fibronectin 1 (Fn1). Cyanidin improves heart function and reduces myocardial damage in mice after MI. Furthermore, cyanidin can prevent cardiomyocyte apoptosis. These effects are most likely caused by suppression of MMP9/2 and control of the Akt signaling pathway, suggesting an appropriate therapeutic target.

14.
Nat Commun ; 15(1): 6365, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075094

RESUMO

Cell fate decisions remain poorly understood at the molecular level. Embryogenesis provides a unique opportunity to analyze molecular details associated with cell fate decisions. Works based on model organisms have provided a conceptual framework of genes that specify cell fate control, for example, transcription factors (TFs) controlling processes from pluripotency to immunity1. How TFs specify cell fate remains poorly understood. Here we report that SALL4 relies on NuRD (nucleosome-remodeling and deacetylase complex) to interpret BMP4 signal and decide cell fate in a well-controlled in vitro system. While NuRD complex cooperates with SALL4 to convert mouse embryonic fibroblasts or MEFs to pluripotency, BMP4 diverts the same process to an alternative fate, PrE (primitive endoderm). Mechanistically, BMP4 signals the dissociation of SALL4 from NuRD physically to establish a gene regulatory network for PrE. Our results provide a conceptual framework to explore the rich landscapes of cell fate choices intrinsic to development in higher organisms involving morphogen-TF-chromatin modifier pathways.


Assuntos
Proteína Morfogenética Óssea 4 , Diferenciação Celular , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase , Fatores de Transcrição , Animais , Camundongos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteína Morfogenética Óssea 4/metabolismo , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/genética , Cromatina/metabolismo , Redes Reguladoras de Genes , Fibroblastos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Endoderma/metabolismo , Endoderma/citologia , Transdução de Sinais , Linhagem da Célula , Proteínas de Ligação a DNA
15.
Data Brief ; 54: 110278, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38962193

RESUMO

This Data in Brief (DiB) article presents the differences in cycling behaviors related to violations, errors, and positive behaviors by region. The study data were collected by means of a structured questionnaire applied to a full sample of 7,001 participants from 19 countries, distributed over 5 continents. This paper proposes descriptive statistics, as well as common statistical tests. The aim is to enable authors to make their own analyses, not to provide precise interpretations. For further information about the macro project supporting the collection of these data, it is advised to refer to the paper titled "Cross-culturally approaching the cycling behavior questionnaire (CBQ): Evidence from 19 countries", published in Transportation Research Part F: Traffic Psychology and Behavior.

16.
Nat Hum Behav ; 7(11): 1899-1916, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37563303

RESUMO

How does economic inequality relate to prosocial behaviour? Existing theories and empirical studies from multiple disciplines have produced mixed results. Here we conduct a systematic review and meta-analysis to systematically synthesize empirical studies. Results from 192 effect sizes and over 2.5 million observations in 100 studies show that the relationship varies from being negative to positive depending upon the study (95% prediction interval -0.450 to 0.343). However, on average, there is a small, negative relationship between economic inequality and prosocial behaviour (r = -0.064, P = 0.004, 95% confidence interval -0.106 to -0.021). There is generally no evidence that results depend upon characteristics of the studies, participants, the way prosocial behaviour and inequality were assessed, and the publication discipline. Given the prevalence of economic inequality and the importance of prosocial behaviour, this systematic review and meta-analysis provides a timely study on the relationship between economic inequality and prosocial behaviour.


Assuntos
Altruísmo , Humanos , Prevalência
17.
Int Immunopharmacol ; 121: 110546, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37364331

RESUMO

The gut microbiome has emerged as a crucial player in developing and progressing cardiovascular diseases (CVDs). Recent studies have highlighted the role of microbial metabolites in modulating immune cell function and their impact on CVD. Macrophages, which have a significant function in the pathogenesis of CVD, are very vulnerable to the effects of microbial metabolites. Microbial metabolites, such as short-chain fatty acids (SCFAs) and trimethylamine-N-oxide (TMAO), have been linked to atherosclerosis and the regulation of immune functions. Butyrate has been demonstrated to reduce monocyte migration and inhibit monocyte attachment to injured endothelial cells, potentially contributing to the attenuation of the inflammatory response and the progression of atherosclerosis. On the other hand, TMAO, another compound generated by gut bacteria, has been linked to atherosclerosis due to its impact on lipid metabolism and the accumulation of cholesterol in macrophages. Indole-3-propionic acid, a tryptophan metabolite produced solely by microbes, has been found to promote the development of atherosclerosis by stimulating macrophage reverse cholesterol transport (RCT) and raising the expression of ABCA1. This review comprehensively discusses how various microbiota-produced metabolites affect macrophage polarization, inflammation, and foam cell formation in CVD. We also highlight the mechanisms underlying these effects and the potential therapeutic applications of targeting microbial metabolites in treating CVD.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Humanos , Metilaminas , Colesterol/metabolismo , Macrófagos/metabolismo , Aterosclerose/metabolismo
18.
Healthcare (Basel) ; 10(10)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36292501

RESUMO

Peer relationships play an important role in the growth of children. This study offers insights about feelings of fear and inferiority in children's peer relationships. Based on a national survey, the 2018 Construction for Social Policy Support System for Urban and Rural Poor Families in China, initiated by the Ministry of Civil Affairs, and using multiple regression models and a structural equation model, this study discusses whether and how having a rural household registration or being from a poor (dibao) family has an isolation effect on fear and inferiority in children's peer relationships. The research findings indicate that children with a rural household registration or those from a dibao family are at a disadvantage in peer interactions. Moreover, rural resident identity has an indirect effect on children's fear of peers and inferiority, mainly through psychological resilience, anxiety and depression, and mobile phone dependence. Being from a dibao family directly influences children's fear and inferiority in their peer relationships; it also indirectly influences fear of peers and inferiority through psychological resilience. This study suggests that more attention should be paid to fear of peers and inferiority in rural children or children from a dibao family.

19.
Artigo em Inglês | MEDLINE | ID: mdl-34574749

RESUMO

To study the influence of the driving environment of an undersea tunnel on driver EEG (electroencephalography) characteristics and driving safety, a real vehicle experiment was performed in the Qingdao Jiaozhou Bay Tunnel. The experimental data of the drivers' real vehicle experiment were collected using an illuminance meter, EEG instrument, video recorder and other experimental equipment. The undersea tunnel is divided into different areas, and the distribution law of driving environment characteristics, EEG characteristics and vehicle speed characteristics is analyzed. The correlations between the driving environment characteristics, EEG characteristics and vehicle speed characteristics model the variables that pass the correlation test. The driving safety evaluation model of an undersea tunnel is established, and the driving safety in different areas of the undersea tunnel is evaluated. The results show that there are obvious differences in illumination, EEG power change rate, vehicle speed and other variables in different areas of the undersea tunnel. The driving environment characteristics are highly correlated with the ß wave power change rate. The driving safety of different areas of the undersea tunnel from high to low is: upslope area, downslope area, exit area and entrance area. The study will provide a theoretical basis for the safe operation of the undersea tunnel.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Eletroencefalografia , Iluminação
20.
Chem Commun (Camb) ; 56(55): 7585-7588, 2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32510076

RESUMO

A new external oxidant-free electrochemical dehydrogenative cross-coupling of xanthenes and ketones for the preparation of functionalized 9-alkyl-9H-xanthenes was developed. This method enables the formation of a new C(sp3)-C(sp3) bond through release of H2 as the major byproduct at room temperature, and features mild conditions, high atom economy, excellent functional-group tolerance, scalability and facile applications in pharmaceutical chemistry.

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