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1.
BMC Plant Biol ; 24(1): 566, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38880875

RESUMEN

BACKGROUND: Plants can retain atmospheric particulate matter (PM) through their unique foliar microstructures, which has a profound impact on the phyllosphere microbial communities. Yet, the underlying mechanisms linking atmospheric particulate matter (PM) retention by foliar microstructures to variations in the phyllosphere microbial communities remain a mystery. In this study, we conducted a field experiment with ten Ulmus lines. A series of analytical techniques, including scanning electron microscopy, atomic force microscopy, and high-throughput amplicon sequencing, were applied to examine the relationship between foliar surface microstructures, PM retention, and phyllosphere microbial diversity of Ulmus L. RESULTS: We characterized the leaf microstructures across the ten Ulmus lines. Chun exhibited a highly undulated abaxial surface and dense stomatal distribution. Langya and Xingshan possessed dense abaxial trichomes, while Lieye, Zuiweng, and Daguo had sparsely distributed, short abaxial trichomes. Duomai, Qingyun, and Lang were characterized by sparse stomata and flat abaxial surfaces, whereas Jinye had sparsely distributed but extensive stomata. The mean leaf retention values for total suspended particulate (TSP), PM2.5, PM2.5-10, PM10-100, and PM> 100 were 135.76, 6.60, 20.10, 90.98, and 13.08 µg·cm- 2, respectively. Trichomes substantially contributed to PM2.5 retention, while larger undulations enhanced PM2.5-10 retention, as evidenced by positive correlations between PM2.5 and abaxial trichome density and between PM2.5-10 and the adaxial raw microroughness values. Phyllosphere microbial diversity patterns varied among lines, with bacteria dominated by Sediminibacterium and fungi by Mycosphaerella, Alternaria, and Cladosporium. Redundancy analysis confirmed that dense leaf trichomes facilitated the capture of PM2.5-associated fungi, while bacteria were less impacted by PM and struggled to adhere to leaf microstructures. Long and dense trichomes provided ideal microhabitats for retaining PM-borne microbes, as evidenced by positive feedback loops between PM2.5, trichome characteristics, and the relative abundances of microorganisms like Trichoderma and Aspergillus. CONCLUSIONS: Based on our findings, a three-factor network profile was constructed, which provides a foundation for further exploration into how different plants retain PM through foliar microstructures, thereby impacting phyllosphere microbial communities.


Asunto(s)
Microbiota , Material Particulado , Hojas de la Planta , Ulmus , Hojas de la Planta/microbiología , Hojas de la Planta/ultraestructura , Ulmus/microbiología , Microscopía Electrónica de Rastreo , Bacterias/clasificación , Bacterias/genética , Biodiversidad
2.
BMC Plant Biol ; 24(1): 555, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38877393

RESUMEN

BACKGROUND: Selenium is essential for livestock and human health. The traditional way of adding selenium to livestock diets has limitations, and there is a growing trend to provide livestock with a safe and efficient source of selenium through selenium-enriched pasture. Therefore, this study was conducted to investigate the effects of selenium enrichment on fermentation characteristics, selenium content, selenium morphology, microbial community and in vitro digestion of silage alfalfa by using unenriched (CK) and selenium-enriched (Se) alfalfa as raw material for silage. RESULTS: In this study, selenium enrichment significantly increased crude protein, soluble carbohydrate, total selenium, and organic selenium contents of alfalfa silage fresh and post-silage samples, and it significantly decreased neutral detergent fiber and acid detergent fiber contents (p < 0.05). Selenium enrichment altered the form of selenium in plants, mainly in the form of SeMet and SeMeCys, which were significantly higher than that of CK (p < 0.05). Selenium enrichment could significantly increase the lactic acid content, reduce the pH value, change the diversity of bacterial community, promote the growth of beneficial bacteria such as Lactiplantibacillus and inhibit the growth of harmful bacteria such as Pantoea, so as to improve the fermentation quality of silage. The in vitro digestibility of dry matter (IVDMD), in vitro digestibility of acid detergent fibers (IVADFD) and in vitro digestibility of acid detergent fibers (IVNDFD) of silage after selenium enrichment were significantly higher than those of CK (p < 0.05). CONCLUSION: This study showed that the presence of selenium could regulate the structure of the alfalfa silage bacterial community and improve alfalfa silage fermentation quality. Selenium enrichment measures can change the morphology of selenium in alfalfa silage products, thus promoting the conversion of organic selenium.


Asunto(s)
Fermentación , Medicago sativa , Microbiota , Selenio , Ensilaje , Medicago sativa/metabolismo , Ensilaje/análisis , Selenio/metabolismo , Animales , Alimentación Animal/análisis
3.
J Environ Manage ; 367: 122016, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39106795

RESUMEN

Driven by the "dual carbon" goal, it is essential to investigate whether companies can enhance carbon emission efficiency by improving Environmental, Social, and Governance (ESG) performance. This study investigates the relationship between ESG ratings and carbon emission efficiency among Chinese A-share listed companies. The study reveals that a higher ESG rating significantly improves carbon efficiency. Mechanism studies indicate that the effect of ESG mainly comes from easing financing constraints, promoting green innovation, and strengthening supervision. Additionally, the study finds that the impact of ESG on carbon emission efficiency is more pronounced in non-heavy polluting and non-state-owned enterprises. Economic policy uncertainty diminishes the positive effects of ESG initiatives on carbon efficiency, while enhanced governmental concerns to environmental significantly bolsters these impacts. This paper offers empirical insights that can inform adjustment of policies concerning ESG performance and carbon emission.


Asunto(s)
Carbono , China , Política Ambiental
4.
Opt Lett ; 48(13): 3407-3410, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37390142

RESUMEN

Acoustic splitters and electromagnetic splitters can be applied in various fields (e.g., navigation and interference detection). However, there is still a lack of study of structures that can simultaneously split acoustic and electromagnetic beams. In this study, a novel, to the best of our knowledge, electromagnetic-acoustic splitter (EAS) based on copper plates is proposed, which can simultaneously produce identical beam-splitting effects for transverse magnetic (TM)-polarized electromagnetic and acoustic waves. Different from previous beam splitters, the beam splitting ratio of the proposed passive EAS can be simply tuned by changing the incident angle of the input beam, i.e., a tunable splitting ratio can be achieved without additional energy consumption. The simulated results verify that the proposed EAS can create two transmitted split beams with a tunable splitting ratio for both electromagnetic and acoustic waves. This may have applications in dual-field navigation/detection, which can provide additional information and higher accuracy compared with single-field navigation/detection.


Asunto(s)
Acústica , Cobre , Sonido , Fenómenos Electromagnéticos
5.
Opt Express ; 30(12): 21386-21395, 2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-36224859

RESUMEN

Cloaks can greatly reduce the scattering cross-section of hidden objects through various mechanisms, thereby making them invisible to outside observers. Among them, the full-space omnidirectional cloak based on transformation optic with full parameters are difficult to realize without metamaterials and often needs to be simplified before realization, while most cloaks with simplified parameters have limited working direction and cannot achieve omnidirectional cloaking effect. In this study, a full-space omnidirectional cloak is designed based on transformation optics and optic-null medium, which only needed natural materials without metamaterials. The designed omnidirectional cloak is realized by subwavelength metal channels filled with isotropic dielectrics whose refractive indices range from 1 to 2, which is homogeneous in each channel. The numerical simulation results verify good scattering suppression effect of the designed cloak for various detecting waves.

6.
J Nanobiotechnology ; 20(1): 437, 2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-36195918

RESUMEN

Photodynamic therapy (PDT), and sonodynamic therapy (SDT) that developed from PDT, have been studied for decades to treat solid tumors. Compared with other deep tumors, the accessibility of urological tumors (e.g., bladder tumor and prostate tumor) makes them more suitable for PDT/SDT that requires exogenous stimulation. Due to the introduction of nanobiotechnology, emerging photo/sonosensitizers modified with different functional components and improved physicochemical properties have many outstanding advantages in cancer treatment compared with traditional photo/sonosensitizers, such as alleviating hypoxia to improve quantum yield, passive/active tumor targeting to increase drug accumulation, and combination with other therapeutic modalities (e.g., chemotherapy, immunotherapy and targeted therapy) to achieve synergistic therapy. As WST11 (TOOKAD® soluble) is currently clinically approved for the treatment of prostate cancer, emerging photo/sonosensitizers have great potential for clinical translation, which requires multidisciplinary participation and extensive clinical trials. Herein, the latest research advances of newly developed photo/sonosensitizers for the treatment of urological cancers, and the efficacy, as well as potential biological effects, are highlighted. In addition, the clinical status of PDT/SDT for urological cancers is presented, and the optimization of the photo/sonosensitizer development procedure for clinical translation is discussed.


Asunto(s)
Neoplasias , Fotoquimioterapia , Terapia por Ultrasonido , Neoplasias de la Vejiga Urinaria , Humanos , Inmunoterapia , Masculino , Neoplasias/tratamiento farmacológico , Fotoquimioterapia/métodos , Terapia por Ultrasonido/métodos , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico
7.
J Nanobiotechnology ; 20(1): 97, 2022 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-35236339

RESUMEN

BACKGROUND: Diabetes mellitus (DM) is considered to be an important factor for bone degeneration disorders such as bone defect nonunion, which is characterized by physical disability and tremendous economy cost to families and society. Exosomal miRNAs of BMSCs have been reported to participate in osteoblastogenesis and modulating bone formation. However, their impacts on the development of bone degeneration in DM are not yet known. The role of miRNAs in BMSCs exosomes on regulating hyperglycemia bone degeneration was investigated in the present study. RESULTS: The osteogenic potential in bone defect repair of exosomes derived from diabetes mellitus BMSCs derived exosomes (DM-Exos) were revealed to be lower than that in normal BMSCs derived exosomes (N-Exos) in vitro and in vivo. Here, we demonstrate that miR-140-3p level was significantly altered in exosomes derived from BMSCs, ADSCs and serum from DM rats. In in vitro experiments, upregulated miR-140-3p exosomes promoted DM BMSCs differentiation into osteoblasts. The effects were exerted by miR-140-3p targeting plxnb1, plexin B1 is the receptor of semaphoring 4D(Sema4D) that inhibited osteocytes differentiation, thereby promoting bone formation. In DM rats with bone defect, miR-140-3p upregulated exosomes were transplanted into injured bone and accelerated bone regeneration. Besides, miR-140-3p in the exosomes was transferred into BMSCs and osteoblasts and promoted bone regeneration by targeting the plexin B1/RohA/ROCK signaling pathway. CONCLUSIONS: Normal-Exos and miR-140-3p overexpressed-Exos accelerated diabetic wound healing by promoting the osteoblastogenesis function of BMSCs through inhibition plexin B1 expression which is the receptor of Sema4D and the plexin B1/RhoA/ROCK pathway compared with diabetes mellitus-Exos. This offers a new insight and a new therapy for treating diabetic bone unhealing.


Asunto(s)
Diabetes Mellitus Experimental , Exosomas , MicroARNs , Animales , Proliferación Celular , Exosomas/metabolismo , Proteínas Activadoras de GTPasa , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Ratas , Receptores de Superficie Celular
8.
Appl Opt ; 61(15): 4571-4578, 2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-36256300

RESUMEN

Ratiometric fluorescent sensors are widely used in biological sensing and immunoassays due to their high sensitivity detection of analytes. The high-ratio value of fluorescence can increase the sensitivity of the fluorescence sensor; in addition, the directional emission can improve the efficiency of light collection and improve the effective use of radiation power. In previous studies, low fluorescence ratios and low directional emission efficiency have restricted the application of ratio fluorescence sensors. Based on the above constraints, this paper proposes an asymmetric hexagonal microcavity structure. By destroying the complete rotational symmetry of the hexagon structure, it achieves high fluorescence ratios and high-efficiency directional emission in the far-field range in the near-infrared wavelength range, which is of significance for the development of high sensitivity fluorescence sensors.


Asunto(s)
Colorantes Fluorescentes , Espectrometría de Fluorescencia , Colorantes Fluorescentes/química
9.
Molecules ; 27(3)2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35164291

RESUMEN

Alcohol (ethanol) is one of the most common addictive psychoactive substances in the world, and alcoholism may result in harmful effects on human health, especially on the nervous system. Flavonoids are regarded as the main active constituent in Epimedium, which has been used to cure some nervous system diseases such as amnesia for over 1000 years. Here, the protective effects of Epimedium flavonoids against ethanol-induced toxicity in retinoic acid (RA)-treated SH-SY5Y cells were investigated. Their mechanism was explored by a label-free proteomic approach combined with bioinformatic analysis for the first time. The results showed that ethanol treatment decreased cell viability by 18%, whereas the viability increased significantly after intervention with Epimedium flavonoids (p < 0.01). According to proteomic and bioinformatic analyses, hundreds of differentially expressed proteins (DEPs) were identified and classified as biological process (GO_BP), cellular component (GO_CC) and molecular function (GO_MF). Among them, GO_MF of DEPs, especially molecular function relevant to G proteins, greatly changed in SH-SY5Y cells pretreated by Epimedium flavonoids. In the alcoholism pathway, the expression of the Gi protein was up-regulated under the influence of ethanol, whereas Epimedium flavonoids could reverse the expression profile, both of which were validated by Western blot assay. In conclusion, Gi protein seemed to be an important factor in the alcoholism pathway to suppress the ethanol-induced toxicity of SH-SY5Y cells. These findings suggest a protective potential of Epimedium flavonoids against ethanol-induced toxicity to neurons via the regulation of Gi protein function.


Asunto(s)
Epimedium , Etanol/efectos adversos , Flavonoides/farmacología , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Tretinoina/farmacología , Epimedium/química , Flavonoides/química , Humanos , Neuronas/metabolismo , Fármacos Neuroprotectores/química , Proteoma/metabolismo
10.
Opt Express ; 29(18): 28167-28177, 2021 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-34614954

RESUMEN

Conventional full-view imaging systems, which often need complicated image processing algorithms to reconstruct full-view images captured by motional/multiple cameras from different views, cannot have good real-time imaging capability. We design curved-to-flat conversion lens (CFCL) based on optic-null medium, which can directly project/image optical patterns from closed object surface onto image plane (e.g., the focal plane of microscopy), and shows good real-time full-view imaging performance. To realize the CFCL, the reduced optic-null medium is designed by subwavelength metal channels filled with homogeneous isotropic dielectrics. Numerical simulation results verify the function of the designed CFCL, which can image various dynamic optical patterns from the closed object surface to the finite-view image plane. The designed CFCL may have many applications in real-timely observing dynamic closed surfaces in full view, e.g., living tissue/cell and soft material's surface.

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