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1.
Environ Monit Assess ; 196(5): 426, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573396

RESUMO

This article, based on OMI data products, utilizes spatial distribution, ozone-sensitive control areas, Pearson correlation methods, and the Ben-MAP model to study the changes in ozone column concentration from 2018 to 2022, along with the influencing factors and the health of populations exposed to ozone. The findings suggest a spatial variation in the ozone column concentration within the study area, with an increasing trend observed from west to east and from south to north. Over time, the ozone column concentration exhibits an initial increase followed by a subsequent decrease, with the peak concentration observed in 2019 at 37.45 DU and the nadir recorded in 2022 at 33.10 DU. The monthly mean distribution exhibits an inverted V-shaped pattern during the warm season from April to September, with a peak in July (46.71 DU) and a trough in April (35.29 DU). The Hetao Plain Oasis area is primarily a NOx control area in sensitive control areas. The concentrations of O3 and precursor HCHO exhibited significant positive correlations with vegetation index and air temperature, while showing significant negative correlations with wind speed and air pressure. The precursor NO2, in contrast, exhibited a significant negative correlation with both the vegetation index and relative humidity. Based on the ground-based monitoring sites and analysis of human health benefits, the study area witnessed 1944.45 deaths attributed to warm season O3 exposure in 2018, with a subsequent reduction in premature deaths by 149.7, 588.2, and 231.75 for the years 2019 to 2021 respectively when compared to the baseline year. In 2021, the observed decrease in warm-season O3 concentration within that region compared to 2018 resulted in a significant reduction, leading to the prevention of 126 premature deaths.


Assuntos
Monitoramento Ambiental , Ozônio , Humanos , Mortalidade Prematura , Ozônio/toxicidade , Estações do Ano , Temperatura
2.
Int J Oncol ; 64(5)2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38488025

RESUMO

Subsequently to the publication of the above article, an interested reader drew to the authors' attention that, in Fig. 1D on p. 1134, the data panels showing the results for the 'Control' and '1 µmol/l GW9662' experiments (on the left hand side of the figure) were overlapping, such that these data had been derived from the same original source where they were intended to show the results from differently performed experiments. The authors were able to re­examine their original data, and realize that the data for the '1 µmol/l GW9662' panel had been selected incorrectly. The corrected version of Fig. 1, now featuring the correct data for the '1 µmol/l GW9662' experiment in Fig. 1D, is shown on the next page, The authors confirm their error did not grossly affect either the results of the conclusions reported in the paper, and are grateful to the Editor of International Journal of Oncology for allowing them this opportunity to publish a Corrigendum. They also apologize to the readership for any inconvenience caused. [International Journal of Oncology 46: 1131-1140, 2015; DOI: 10.3892/ijo.2015.2829].

3.
Opt Express ; 32(3): 3234-3240, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297549

RESUMO

In this work, the momentum mismatching based on which the acousto-optic (AO) transfer function and diffraction efficiency was acquired, was calculated considering the properties of AO crystals in AO interactions in acousto-optic tunable filter (AOTF). Transfer functions were obtained using a 4f optical system combined with AOTF and compared with theoretical calculations. It demonstrated the influence of acoustic energy shift on the AO interaction which should be considered in the design of AOTF.

4.
Int J Mol Sci ; 24(20)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37894780

RESUMO

The NAC gene family has transcription factors specific to plants, which are involved in development and stress response and adaptation. In this study, ZmNAC89, an NAC gene in maize that plays a role in saline-alkaline tolerance, was isolated and characterized. ZmNAC89 was localized in the nucleus and had transcriptional activation activity during in vitro experiments. The expression of ZmNAC89 was strongly upregulated under saline-alkaline, drought and ABA treatments. Overexpression of the ZmNAC89 gene in transgenic Arabidopsis and maize enhanced salt tolerance at the seedling stage. Differentially expressed genes (DEGs) were then confirmed via RNA-sequencing analysis with the transgenic maize line. GO analyses showed that oxidation-reduction process-regulated genes were involved in ZmNAC89-mediated salt-alkaline stress. ZmNAC89 may regulate maize saline-alkali tolerance through the REDOX pathway and ABA signal transduction pathway. From 140 inbred maize lines, 20 haplotypes and 16 SNPs were found in the coding region of the ZmNAC89 gene, including the excellent haplotype HAP20. These results contribute to a better understanding of the response mechanism of maize to salt-alkali stress and marker-assisted selection during maize breeding.


Assuntos
Tolerância ao Sal , Zea mays , Tolerância ao Sal/genética , Zea mays/metabolismo , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Melhoramento Vegetal , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Álcalis/metabolismo , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética , Secas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
6.
Int J Mol Sci ; 23(20)2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36293196

RESUMO

Seed storability is an important trait for improving grain quality and germplasm conservation, but little is known about the regulatory mechanisms and gene networks involved. MicroRNAs (miRNAs) are small non-coding RNAs regulating the translation and accumulation of their target mRNAs by means of sequence complementarity and have recently emerged as critical regulators of seed germination. Here, we used the germinating embryos of two maize inbred lines with significant differences in seed storability to identify the miRNAs and target genes involved. We identified a total of 218 previously known and 448 novel miRNAs by miRNA sequencing and degradome analysis, of which 27 known and 11 newly predicted miRNAs are differentially expressed in two maize inbred lines, as measured by Gene Ontology (GO) enrichment analysis. We then combined transcriptome sequencing and real-time quantitative polymerase chain reaction (RT-PCR) to screen and confirm six pairs of differentially expressed miRNAs associated with seed storability, along with their negative regulatory target genes. The enrichment analysis suggested that the miRNAs/target gene mediation of seed storability occurs via the ethylene activation signaling pathway, hormone synthesis and signal transduction, as well as plant organ morphogenesis. Our results should help elucidate the mechanisms through which miRNAs are involved in seed storability in maize.


Assuntos
Germinação , MicroRNAs , Germinação/genética , Zea mays/genética , Zea mays/metabolismo , Transcriptoma , MicroRNAs/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Sementes/genética , Sementes/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Etilenos/metabolismo , Hormônios/metabolismo
7.
Sensors (Basel) ; 22(15)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35957351

RESUMO

In underwater acoustic communication (UAC) systems, the channel characteristics are mainly affected by spatiotemporal changes, which are specifically manifested by two factors: the effects of refraction and scattering caused by seawater layered media on the sound field and the random fluctuations from the sea floor and surface. Due to the time-varying and space-varying characteristics of a channel, the communication signals have significant variations in time and space. Furthermore, the signal shows frequency-selective fading in the frequency domain and signal waveform distortion in the time domain, which seriously affect the performance of a UAC system. Techniques such as error correction coding or space diversity are usually adopted by UAC systems to neutralize or eliminate the effects of deep fading and signal distortion, which results in a significant waste of limited communication resources. From the perspective of the sound field, this study used experimental data to analyze the spatiotemporal fluctuation characteristics of the signal and noise fields and then summarized the temporal and spatial variation rules. The influence of the system then guided the parameter configuration and network protocol optimization of the underwater acoustic communication system by reasonably selecting the communication signal parameters, such as frequency, bandwidth, equipment deployment depth, and horizontal distance.


Assuntos
Acústica , Som , Comunicação , Ruído , Espectrografia do Som
8.
Plant Cell Rep ; 41(9): 1863-1874, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35781542

RESUMO

KEY MESSAGE: Exogenous brassinolide promotes Fe absorption through mechanism I strategy, thus improving the tolerance of Malus hupehensis seedlings to Fe deficiency stress. Iron (Fe) deficiency is a common nutritional disorder that results in decreased yield and poor fruit quality in apple production. As a highly active synthetic analog of brassinosteroids, brassinolide (BL) plays numerous roles in plant responses to abiotic stresses. However, its role in Fe deficiency stress in apple plants has never been reported. Herein, we found that the exogenous application of 0.2 mg L-1 BL could significantly enhance the tolerance of apple seedlings to Fe deficiency stress and result in a low etiolation rate and a high photosynthetic rate. The functional mechanisms of this effect were also explored. We found that first, exogenous BL could improve Fe absorption through the mechanism I strategy. BL induced the activity of H+-ATPase and the expression of MhAHA family genes, resulting in rhizosphere acidification. Moreover, BL could enhance the activity of Fe chelate reductase and absorb Fe through direct binding with the E-box of the MhIRT1 or MhFRO2 promoter via the transcription factors MhBZR1 and MhBZR2. Second, exogenous BL alleviated osmotic stress by increasing the contents of osmolytes (proline, solution proteins, and solution sugar) and scavenged reactive oxygen species by improving the activities of antioxidant enzymes. Lastly, exogenous BL could cooperate with other endogenous plant hormones, such as indole-3-acetic acid, isopentenyl adenosine, and gibberellic acid 4, that respond to Fe deficiency stress indirectly. This work provided a theoretical basis for the application of exogenous BL to alleviate Fe deficiency stress in apple plants.


Assuntos
Malus , Esteroides Heterocíclicos , Brassinosteroides/metabolismo , Brassinosteroides/farmacologia , Malus/genética , Plântula , Esteroides Heterocíclicos/farmacologia , Estresse Fisiológico/genética
9.
Bioresour Technol ; 349: 126787, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35134525

RESUMO

Fresh HZSM-5 catalyst modification experiment was carried out on the direct non-thermal plasma (DNTP) reactor. The aim of this work was to study the effects of modified voltages on the physicochemical properties of HZSM-5 and its enhancement in biomass catalytic pyrolysis. The results showed that DNTP modification was performed at different voltages of 20 kV, 22 kV, 24 kV, compared with fresh HZSM-5, the effect of 22 kV voltage was preferably. H-22 had the largest specific surface area and mesoporous volume, and the total acid content added 17.02%. The biomass catalytic pyrolysis test was used to test the HZSM-5 catalytic activity after modification. The results showed that the catalyst obtained by the catalyst under 22 kV modified voltage had the highest monocyclic aromatic hydrocarbon selectivity of 40.55%.


Assuntos
Biocombustíveis , Gases em Plasma , Biomassa , Catálise , Temperatura Alta , Pirólise
10.
Sensors (Basel) ; 18(4)2018 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-29659517

RESUMO

The Unmanned Surface Vehicle (USV) integrated with an acoustic modem is a novel mobile vehicle for data collection, which has an advantage in terms of mobility, efficiency, and collection cost. In the scenario of data collection, the USV is controlled autonomously along the planning trajectory and the data of underwater nodes are dynamically collected. In order to improve the efficiency of data collection and extend the life of the underwater nodes, a mobile data collection protocol for underwater nodes using the USV was proposed. In the protocol, the stop-and-wait ARQ transmission mechanism is adopted, where the duty cycle is designed considering the ratio between the sleep mode and the detection mode, and the transmission ratio is defined by the duty cycle, wake-up signal cycles, and USV’s speed. According to protocol, the evaluation index for energy consumption is constructed based on the duty cycle and the transmission ratio. The energy consumption of the protocol is simulated and analyzed using the mobile communication experiment data of USV, taking into consideration USV’s speed, data sequence length, and duty cycle. Optimized protocol parameters are identified, which in turn denotes the proposed protocol’s feasibility and effectiveness.

11.
Int J Oncol ; 46(3): 1131-40, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25586304

RESUMO

The peroxisome proliferator-activated receptor γ (PPARγ) is emerging as an important regulator in various metabolic processes of cancer. Genistein, as a major isoflavonoid isolated from dietary soybean, possesses a wide variety of biological activities, particularly, in cancer prevention. However, the mechanisms by which genistein elicits its growth inhibiting effects in osteosarcoma (OS) MG-63 cells have not been extensively elucidated. MG-63 cells were treated for 2 days with various concentrations of genistein and/or GW9662 (a selective antagonist of PPARγ). The effect of different drugs on cell viability was determined by Cell Counting Kit-8 (CCK-8). The assay of cell proliferation was performed using 5-ethynyl-2'-deoxyuridine (EdU). The changes of apoptosis and cell cycle progression were detected by flow cytometry experiments. The protein expression of PPARγ pathway (PPARγ, PTEN, BCL-2, Survivin, P21WAF1/CIP1 and Cyclin B1) was determined by western blot analysis. The expression of PPARγ and PTEN mRNA was detected by real-time quantitative RT-PCR analysis. We report that genistein caused OS cell growth inhibition. We found that the PPARγ expression in OS cells increased after genistein treatment. Further studies on the mechanisms of genistein revealed a series of cell growth changes related to the PPARγ pathway; while cell cycle changes can be reversed by GW9662. Genistein plays an important role in preventing OS cell growth, which can impede the OS cell cycle as a non-toxic activator of PPARγ, providing novel insights into the mechanisms of the therapeutic activities of genistein.


Assuntos
Anticarcinógenos/farmacologia , Neoplasias Ósseas/patologia , Proliferação de Células/efeitos dos fármacos , Genisteína/farmacologia , Osteossarcoma/patologia , PPAR gama/metabolismo , Anilidas/farmacologia , Neoplasias Ósseas/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Osteossarcoma/genética , PPAR gama/antagonistas & inibidores , PPAR gama/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
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