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1.
Biochem Cell Biol ; 102(1): 60-72, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37816258

RESUMEN

Acute T-lymphocyte leukemia (T-ALL) is a malignant tumor disease. RNA-binding protein neotumor ventral antigen-1 (NOVA1) is highly expressed in bone marrow mononuclear cells of T-ALL patients, while the role of NOVA1 in T-ALL progression remains unknown. The gain- and loss-of-function studies for NOVA1 were performed in Jurkat and CCRF-CEM cells. NOVA1 overexpression promoted cell proliferation and cell cycle progression. NOVA1 knockdown increased the apoptosis rate of T-ALL cells. Ubiquitin-specific protease 44 (USP44), a nuclear protein with deubiquitinase catalytic activity, has been reported to play an oncogene role in human T-cell leukemia. USP44 expression was positively associated with NOVA1, and RNA immunoprecipitation assay verified the binding of NOVA1 to the mRNA of USP44. USP44 knockdown partially abolished NOVA1-induced cell proliferation and inhibition of apoptosis. The in vivo xenograft experiment was performed by injection of T-ALL tumor cells into the tail vein of NOD/SCID mice. The knockdown of NOVA1 had lower tumorigenicity. NOVA1 knockdown alleviated pathological changes in lung and spleen tissues, and increased the overall survival period and the weight of T-ALL mice. Thus, NOVA1 acts as an accelerator in T-ALL, and its function might be achieved by binding to and stabilizing USP44 mRNA.


Asunto(s)
Antígeno Ventral Neuro-Oncológico , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Humanos , Ratones , Animales , ARN Mensajero/genética , Línea Celular Tumoral , Ratones Endogámicos NOD , Ratones SCID , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Linfocitos T/metabolismo , Ubiquitina Tiolesterasa/genética , Ubiquitina Tiolesterasa/metabolismo
2.
Nano Lett ; 23(6): 2239-2246, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36857481

RESUMEN

Halogen wastewater greatly threatens the health of human beings and aquatic organisms due to its severe toxicity, corrosiveness, and volatility. Efficient bromine removal is therefore urgently required, while existing Br2-capture materials often face challenges from limited water stability and possible halogen leaking. We report a facile and efficient aqueous Br2 removal method using submicron resorcinol-formaldehyde (RF) resin nanoparticles (NPs). The abundant aromatic groups dominate the Br2 removal by substitution reactions. An excellent Br2 conversion capacity of 7441 mg gRF-1 was achieved by RF NPs that outperform state-of-the-art materials by ∼2-fold, along with advantages including good water stability, low cost, and easy fabrication. Two recycling-coupled (electrochemical or H2O2-involved) Br2 removal routes further reveal the feasibility of in-depth halogen removal by RF NPs. The brominated resin can be downstream upcycled for silver recovery, realizing the harvesting of precious metal, reducing of heavy-metal pollution, and resource utilization of brominated resin.

3.
Plant Mol Biol ; 112(1-2): 85-98, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37103774

RESUMEN

The Orchidaceae is a large family of perennial herbs especially noted for the exceptional diversity of specialized flowers. Elucidating the genetic regulation of flowering and seed development of orchids is an important research goal with potential utility in orchid breeding programs. Auxin Response Factor (ARF) genes encode auxin-responsive transcription factors, which are involved in the regulation of diverse morphogenetic processes, including flowering and seed development. However, limited information on the ARF gene family in the Orchidaceae is available. In this study, 112 ARF genes were identified in the genomes of 5 orchid species (Apostasia shenzhenica, Dendrobium catenatum, Phalaenopsis aphrodite, Phalaenopsis equestris and Vanilla planifolia,). These genes were grouped into 7 subfamilies based on their phylogenetic relationships. Compared with the ARF family in model plants, such as Arabidopsis thaliana and Oryza sativa, one group of ARF genes involved in pollen wall synthesis has been lost during evolution of the Orchidaceae. This loss corresponds with absence of the exine in the pollinia. Through mining of the published genomic and transcriptomic data for the 5 orchid species: the ARF genes of subfamily 4 may play an important role in flower formation and plant growth, whereas those of subfamily 3 are potentially involved in pollen wall development. the study results provide novel insights into the genetic regulation of unique morphogenetic phenomena of orchids, which lay a foundation for further analysis of the regulatory mechanisms and functions of sexual reproduction-related genes in orchids.


Asunto(s)
Orchidaceae , Orchidaceae/genética , Transcriptoma , Filogenia , Fitomejoramiento , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Flores/genética , Flores/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
4.
Plant Physiol ; 188(4): 2182-2198, 2022 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-35157078

RESUMEN

Primary thickening determines bamboo yield and wood property. However, little is known about the regulatory networks involved in this process. This study identified a total of 58,652 genes and 150 miRNAs via transcriptome and small RNA sequencing using the underground thickening shoot samples of wild-type (WT) Moso bamboo (Phyllostachys edulis) and a thick wall (TW) variant (P. edulis "Pachyloen") at five developmental stages (WTS1/TWS1-WTS5/TWS5). A total of 14,029 (65.17%) differentially expressed genes and 68 (45.33%) differentially expressed miRNAs were identified from the WT, TW, and WTTW groups. The first two groups were composed of four pairwise combinations, each between two successive stages (WTS2/TWS2_versus_WTS1/TWS1, WTS3/TWS3_versus_WTS2/TWS2, WTS4/TWS4_versus_WTS3/TWS3, and WTS5/TWS5_versus_WTS4/TWS4), and the WTTW group was composed of five combinations, each between two relative stages (TWS1-5_versus_WTS1-5). Additionally, among the phytohormones, zeatin showed more remarkable changes in concentrations than indole-3-acetic acid, gibberellic acid, and abscisic acid throughout the five stages in the WT and the TW groups. Moreover, 125 cleavage sites were identified for 387 miRNA-mRNA pairs via degradome sequencing (P < 0.05). The dual-luciferase reporter assay confirmed that 13 miRNAs bound to 12 targets. Fluorescence in situ hybridization localized miR166 and miR160 in the shoot apical meristem and the procambium of Moso bamboo shoots at the S1 stage. Thus, primary thickening is a complex process regulated by miRNA-gene-phytohormone networks, and the miRNAome and transcriptome dynamics regulate phenotypic plasticity. These findings provide insights into the molecular mechanisms underlying wood formation and properties and propose targets for bamboo breeding.


Asunto(s)
Fitomejoramiento , Transcriptoma , Regulación de la Expresión Génica de las Plantas , Hibridación Fluorescente in Situ , Reguladores del Crecimiento de las Plantas/metabolismo , Poaceae/genética , Poaceae/metabolismo , Transcriptoma/genética
5.
Clin Immunol ; 245: 109134, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36184053

RESUMEN

Peptidyl arginine deiminase (PAD) which mediates citrullination catalyzes the conversion of arginine residues of protein peptide chains to citrulline residues. Citrullination can be involved in the process of apoptosis, embryo development, regulation of myelin sheath function and other physiological processes. Besides, it can regulate the process of cell death, affect the formation of neutrophil extracellular traps (NETs) and produce anti-citrullinated protein antibody (ACPA) to participate in autoimmune diseases. In this manuscript, the regulatory effects of citrullination in normal physiology and autoimmune diseases are reviewed, and the effects of citrullination on immune cells in autoimmune diseases are discussed in detail.


Asunto(s)
Enfermedades Autoinmunes , Trampas Extracelulares , Humanos , Citrulinación , Desiminasas de la Arginina Proteica/genética , Desiminasas de la Arginina Proteica/metabolismo , Trampas Extracelulares/metabolismo , Citrulina
6.
Opt Express ; 30(7): 10354-10366, 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35473005

RESUMEN

We first present the all-optical realization of a scalable super-resolved magnetic vortex core (MVC) by tightly focusing two modulated counter-propagating radially polarized doughnut Gaussian beams based on the vectoial diffraction theory and the inverse Faraday effect. It is shown that by imposing spiral phase plates (SPPs) on the incident vectorial beams, single three-dimensional (3D) super-resolved (λ3/22) MVC can be achieved in the 4π focusing setup, which is radically different from that produced with a single lens focusing. Furthermore, the light-induced MVC texture turns to be richer and more complex when the radially polarized beams are tailored by the SPPs and judiciously designed multi-ring filters all together. In this case, we are able to garner not only transverse super-resolved (0.447λ) MVC needle with an uniformly extended area (40λ) in the single lens focusing system, but also the multiple uniform 3D super-resolved (λ3/24) chain-like MVC cells in the 4π focusing system, thus giving rise to the tunable and scalable super-resolved MVC extension. The related physical mechanisms to trigger such peculiar magnetization polarization topologies are unraveled as well. These resultant achievements would pave the way for the integrated transfer and storage of optomagnetic information, atomic trapping, and beyond.

7.
Opt Express ; 29(16): 26137-26149, 2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-34614926

RESUMEN

We present an all-optical scheme for the generation of longitudinal magnetization superoscillation based on the vectorial diffraction theory and the inverse Faraday effect. To achieve this, an azimuthally polarized high-order Laguerre-Gaussian vortex mode is firstly focused by a high numerical aperture (NA) objective and then impinges on an isotropic magneto-optical material. It is found that, by judiciously controlling the intrinsic arguments (radial mode index (p) and truncation parameter (ß)) of such a configurable vectorial vortex beam, the longitudinal magnetic domain induced in the focal plane can be switched from a peak sub-wavelength magnetization (> 0.36λ/NA), via the fastest Fourier magnetization component (∼0.36λ/NA), to a super-oscillation magnetization hotspot (< 0.36λ/NA). We further examine the dependence of the transverse size, the side lobe, and the energy conversion efficiency within the focal magnetization domain on both the p and ß of the initial vortex modes, confirming that the higher-order structured vortex beams are preferable alternatives to trigger robust longitudinal magnetization superoscillation. In addition, the underlying mechanisms behind the well-defined magnetization phenomena are unveiled. The ultra-small-scale longitudinal magnetization demonstrated here may hold massive potential applications in high-density all-optical magnetic recording/storage, super-resolution magnetic resonance imaging, atom trapping and spintronics.

8.
Molecules ; 25(9)2020 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-32403284

RESUMEN

Bamboo-plastic composites (BPCs) as new biomass-plastic composites have recently attracted much attention. However, weak mechanical performance and high moisture absorption as well as low thermal stability greatly limit their industrial applications. In this context, different amounts of halloysite nanotubes (HNTs) were used as a natural reinforcing filler for BPCs. It was found that the thermal stability of BPCs increased with increasing HNT contents. The mechanical strength of BPCs was improved with the increase in HNT loading up to 4 wt% and then worsened, while the impact strengths were slightly reduced. Low HNT content (below 4 wt%) also improved the dynamic thermomechanical properties and reduced the water absorption of the BPCs. Morphological studies confirmed the improved interfacial compatibility of the BPC matrix with 4 wt% HNT loading, and high-concentration HNT loading (above 6 wt%) resulted in easy agglomeration. The results highlight that HNTs could be a feasible candidate as nanoreinforcements for the development of high-performance BPCs.


Asunto(s)
Arcilla/química , Nanotubos/química , Plásticos/química , Sasa/química , Biomasa , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Nanotubos/ultraestructura , Temperatura , Agua/química
9.
Int J Mol Sci ; 20(21)2019 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-31694142

RESUMEN

We developed a novel green approach for the in situ fabrication of Ag NPs in mesoporous TiO2 films via the bamboo self-sacrificing reduction of Ag(NH3)2+ ions, which can inhibit fungal growth on the bamboo surface. Mesoporous anatase TiO2 (MT) films were first synthesized on bamboo via a hydrothermal method. Then, Ag NPs with a 5.3 nm mean diameter were incorporated into the pore channels of optimal MT/bamboo (MTB) samples at room temperature without the addition of reducing agents, such that the Ag NPs were almost entirely embedded into the MT films. Our analysis indicated that the solubilized lignin from bamboo, which is rich in oxygen-containing functional groups, serves as a green reductant for reducing the Ag(NH3)2+ ions to Ag NPs. Antifungal experiments with Trichoderma viride under dark conditions highlighted that the antifungal activity of the Ag/MT/bamboo samples were greater than those of naked bamboo, MTB, and Ag/bamboo, suggesting that these hybrid nanomaterials produce a synergistic antifungal effect that is unrelated to photoactivity. The inhibition of Penicillium citrinum effectively followed a similar trend. This newly developed bamboo protection method may provide a sustainable, eco-friendly, and efficient method for enhancing the antifungal characteristics of traditional bamboo, having the potential to prolong the service life of bamboo materials, particularly under dark conditions.


Asunto(s)
Antifúngicos/química , Nanocompuestos/química , Plata/química , Titanio/química , Antifúngicos/farmacología , Materiales de Construcción/microbiología , Humanos , Nanopartículas del Metal/química , Micosis/microbiología , Micosis/prevención & control , Penicillium/efectos de los fármacos , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Porosidad , Sasa/química , Sasa/microbiología , Plata/farmacología , Titanio/farmacología , Trichoderma/efectos de los fármacos
10.
Planta ; 248(4): 849-858, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29938358

RESUMEN

MAIN CONCLUSION: Both G units and S units deposited in the whole lignification process of xylem fiber. The topochemical variations in newly formed xylem and phloem of Populus × euramericana were investigated by combined microscopic techniques. During xylem formation, earlier cell wall deposition in vessel and afterwards in the neighboring fiber was observed in situ. Raman images in xylem fiber emphasized that cell wall deposition was an ordered process which lignification started in cell corner following carbohydrates deposition. Higher deposition speed of carbohydrates was revealed at the beginning of the cell wall differentiation, and the syringyl (S) units deposition was more pronounced compared with guaiacyl (G) units at the earlier stage of lignification. The comparative analysis of cell wall composition in phloem fiber indicated that phloem formed earlier than xylem and the distribution of lignin monomers varied significantly with phloem fiber location. Furthermore, an interesting phenomenon was found that the outermost phloem fiber near the periderm displayed a multilayered structure with alternating broad and narrow layer, and the broad lamellae showed higher concentration of carbohydrates and S lignin. The cytological information including cell wall composition and lignin structure of xylem and phloem might be helpful to understand the wood growth progresses and facilitate utilization of woody plants.


Asunto(s)
Pared Celular/química , Floema/citología , Populus/citología , Xilema/citología , Metabolismo de los Hidratos de Carbono , Carbohidratos/análisis , Pared Celular/metabolismo , Celulosa/análisis , Lignina/análisis , Microscopía Fluorescente , Microscopía de Polarización , Polímeros/análisis , Espectrometría Raman , Xilema/crecimiento & desarrollo
11.
Phys Rev Lett ; 120(12): 123901, 2018 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-29694063

RESUMEN

We achieve long-range and continuous optical pulling in a periodic photonic crystal background, which supports a unique Bloch mode with the self-collimation effect. Most interestingly, the pulling force reported here is mainly contributed by the intensity gradient force originating from the self-induced backaction of the object to the self-collimation mode. This force is sharply distinguished from the widely held conception of optical tractor beams based on the scattering force. Also, this pulling force is insensitive to the angle of incidence and can pull multiple objects simultaneously.

12.
Langmuir ; 34(36): 10537-10542, 2018 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-30117740

RESUMEN

The spatial cross-correlated diffusion of colloidal particles is often used as an essential tool to study the dynamic properties of a fluid because it directly describes the hydrodynamic interaction between two particles in a fluid. However, the experimental measurement of cross-correlated diffusion can be substantially modified by even a weak shear flow. In this work, the effect of a shear flow on spatial cross-correlated diffusion is demonstrated using experimental measurements that show a clear dependence on pair angles. An analytical solution is proposed to explain the experimental observations. A numerical simulation is performed to systemically demonstrate the influence of shear flow on spatial cross-correlated diffusion. The results of the experiment, theoretical analysis, and numerical simulation agree well with each other. Therefore, this research provides a sensitive experimental method to determine the weak shear flow in any quasi-two-dimensional fluid systems.

13.
Opt Express ; 24(16): 18436-44, 2016 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-27505807

RESUMEN

Optical evanescent wave in total internal reflection has been widely used in efficient optical manipulation, where the object is trapped by the intrinsic intensity gradient of the evanescent wave while transported by the scattering force along the orthogonal direction. Here, we propose a distinct optical manipulation scheme using the attenuated modes in subwavelength optical channels, where both the trapping and transportation forces are along the channel direction. We create such a mode in a sub-wavelength photonic crystal waveguide and quantitatively obtain the net pushing and pulling forces, which can overcome the Brownian motion within a critical length. Due to the presence of the physical channel, subwavelength trapping on the transverse direction is natural, and manipulation along bend trajectories is also possible without the assistance of the self-acceleration beams provided a channel is adopted. This optical manipulation method can be extended to any other channels that support attenuation mode, and may provide an alternate way for flexible optical manipulation.

14.
Biosci Biotechnol Biochem ; 78(10): 1738-42, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25273139

RESUMEN

Pollen Typhae total flavone (PTF), the extract from Pollen Typhae, is reported to enhance glucose uptake in C2C12 myotubes in vitro, but the convincing evidence is lacking in vivo. In this study, PTF ameliorated insulin resistance and dyslipidemia, but failed to significantly increase body weight in type 2 diabetic rats induced by high-fat diet and low-dose streptozotocin.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Dieta Alta en Grasa/efectos adversos , Flavonas/farmacología , Resistencia a la Insulina , Typhaceae/química , Animales , Peso Corporal/efectos de los fármacos , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/fisiopatología , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos/efectos de los fármacos , Flavonas/uso terapéutico , Lípidos/sangre , Ratas
15.
Clin Transl Oncol ; 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38558284

RESUMEN

First-in-human (FIH) dose-escalation trials on oncology should prioritize safety and emphasize efficacy. We reviewed the FIH trials of 67 anti-tumor products approved by the Food and Drug Administration between 2018 and 2023 and found that the "3 + 3" design remains the predominant dose-escalation method (66.2%). The number of patients receiving sub-therapeutic doses is positively correlated with the maximum tolerated dose (MTD) or maximum dose (MD) to starting dose ratio (P = 0.056) and the number of dose levels in trials (P < 0.001). In addition, the proportion of products with a high ratio in antibody drugs is higher than that in small molecules (P < 0.001). The MTD or MD exceeded the label dose by three or more doses in 22.03% of the products. In conclusion, optimizing the starting dose selection method, refining the way of determining doses, and finding alternative indicators to replace toxicity as the endpoints will increase the effectiveness and broaden the beneficiary scope.

16.
PeerJ ; 12: e16914, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38406281

RESUMEN

Background: Paphiopedilum armeniacum (P. armeniacum), an ornamental plant native to China, is known for its distinctive yellow blossoms. However, the mechanisms underlying P. armeniacum flower coloration remain unclear. Methods: We selected P. armeniacum samples from different flowering stages and conducted rigorous physicochemical analyses. The specimens were differentiated based on their chemical properties, specifically their solubilities in polar solvents. This key step enabled us to identify the main metabolite of flower color development of P. armeniacum, and to complete the identification by High-performance liquid chromatography (HPLC) based on the results. Additionally, we employed a combined approach, integrating both third-generation full-length transcriptome sequencing and second-generation high-throughput transcriptome sequencing, to comprehensively explore the molecular components involved. Results: We combined physical and chemical analysis with transcriptome sequencing to reveal that carotenoid is the main pigment of P. armeniacum flower color. Extraction colorimetric method and HPLC were used to explore the characteristics of carotenoid accumulation during flowering. We identified 28 differentially expressed carotenoid biosynthesis genes throughout the flowering process, validated their expression through fluorescence quantification, and discovered 19 potential positive regulators involved in carotenoid synthesis. Among these candidates, three RCP2 genes showed a strong potential for governing the PDS and ZDS gene families. In summary, our study elucidates the fundamental mechanisms governing carotenoid synthesis during P. armeniacum flowering, enhancing our understanding of this process and providing a foundation for future research on the molecular mechanisms driving P. armeniacum flowering.


Asunto(s)
Perfilación de la Expresión Génica , Transcriptoma , Transcriptoma/genética , Perfilación de la Expresión Génica/métodos , Carotenoides/metabolismo , Flores/genética , China
17.
Curr Pharm Des ; 29(5): 379-392, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36803762

RESUMEN

BACKGROUND: At present, there are no effective pharmacologic therapies for attenuating the course of osteoarthritis (OA) in humans and current therapies are geared to mitigating symptoms. Fangfeng decoction (FFD) is a traditional Chinese medicine prescribed for the treatment of OA. In the past, FFD has achieved positive clinical outcomes in alleviating the symptoms of OA in China. However, its mechanism of action has not yet been clarified. OBJECTIVE: The objective of this study is to investigate and explore the mechanism of FFD and how the compound interacts with the target of OA; network pharmacology and molecular docking methods were applied in this study. METHODS: The active components of FFD were screened by Traditional Chinese Medicine Systems Pharmacology (TCMSP) database according to the inclusion criteria as oral bioactivity (OB) ≥ 30% and drug likeness (DL) ≥ 0.18. Then, gene name conversion was performed through the UniProt website. The related target genes of OA were obtained from the Genecards database. Core components, targets, and signaling pathways were obtained through compound-target-pathway (C-T-P) and protein-protein interaction (PPI) networks were built using Cytoscape 3.8.2 software. Matescape database was utilized to get gene ontology (GO) function enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment of gene targets. The interactions of key targets and components were analyzed by molecular docking in Sybyl 2.1 software. RESULTS: A total of 166 potential effective components, 148 FFD-related targets, and 3786 OA-related targets were obtained. Finally, 89 common potential target genes were confirmed. Pathway enrichment results showed that HIF-1 and CAMP signaling pathways were considered key pathways. The screening of core components and targets was achieved through the CTP network. The core targets and active components were obtained according to the CTP network. The molecular docking results showed that quercetin, medicarpin, and wogonin of FFD could bind to NOS2, PTGS2, and AR, respectively. CONCLUSION: FFD is effective in the treatment of OA. It may be caused by the effective binding of the relevant active components of FFD to the targets of OA.


Asunto(s)
Apiaceae , Medicamentos Herbarios Chinos , Humanos , Simulación del Acoplamiento Molecular , Farmacología en Red , China , Ciclooxigenasa 2 , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Medicina Tradicional China
18.
Plants (Basel) ; 12(16)2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37631198

RESUMEN

Unlike the culm hollow structure of most bamboo species, Oxytenanthera abyssinica has a unique solid or semi-solid culm, which may endow it with superior mechanical performance. In this study, the variation in fiber morphology and micro-mechanical properties across the radial regions of bamboo culm was examined by optical microscopy, scanning electron microscopy, X-ray diffraction, and nanoindentation. Results showed that the mean values of vascular bundle frequency and fiber tissue proportion were 1.76 pcs/mm2 and 21.04%, respectively, both of which increased gradually from inner to outer. The mean length, diameter, and length-diameter ratio of the fiber were 2.10 mm, 21.54 µm, and 101.41 respectively. The mean indentation modulus of elasticity (IMOE) and hardness were 21.34 GPa and 545.88 MPa. The IMOE exhibited a significant increase from the inner to the middle region, and little change was observed from the middle to the outer region. There were slight fluctuations in hardness along the radial direction. The mean crystallinity and microfibril angle(MFA) of the fibers was 68.12% and 11.26 degrees, respectively. There is a positive correlation between cellulose crystallinity and the IMOE and hardness, while there is a negative correlation between the MFA and the IMOE and the hardness.

19.
Plants (Basel) ; 12(7)2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37050084

RESUMEN

Plants of the genus Narcissus are well-known for their characteristic corona morphology, which structural origins have been a bone of contention among scholars. With "Jinzhanyintai" (JZ) and "Yulinglong" (YLL)-two major close-originated cultivars of Chinese narcissus (Narcissus tazetta L. var. chinensis Roem)-as materials, anatomic observation was made on floral organs during corona morphogenesis by dissection with hands under a stereomicroscope, paraffin section, scanning electron microscopy, and high-resolution X-ray tomography. It was uncovered that corona primordia of both cultivars appeared following the end of the differentiation of other floral organs, with differentiation sites located at the inner wall of the juncture of the base of tepals and the upper margin of the hypanthium. Affected by staminal filaments, the corona primordia of JZ experienced a three-stage differentiation process, namely blockage from the second whorl of stamens, blockage from the first whorl of stamens, and healing of corona primordia. However, the expanded spatial structure of the first whorl of petal-like stamens blocked the path of differentiation of YLL corona primordia, giving rise to slow differentiation of the corona primordia at the base of the first whorl of petal-like stamens and malformed differentiation of the corona primordia in the interval between the two whorls of petal-like stamens. Thus, a fragmented structure consisting of typical and fragmented coronas was formed. Furthermore, petal-like stamens of YLL in the lower part had a corona-like morphology. The spatio-temporal specificity of corona differentiation convincingly demonstrates that the corona is a structure independent of and different from the typical four whorls of floral organs, but also highly correlated with stamen.

20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(9): 2405-8, 2012 Sep.
Artículo en Zh | MEDLINE | ID: mdl-23240406

RESUMEN

Rosewood is a kind of precious wood which include many wood species. It's difficult to most people to identify rosewood species. Near infrared spectroscopy (NIR) of eight rosewood species was investigated in the present paper. The results showed that (1) there was significant correlation between near infrared spectroscopy and color parameters expressed by L*, a* and b* values of rosewood, the correlation coefficients between NIR predicted and laboratory measured L* , a* and b* values were 0.988, 0.991 and 0.993, respectively; (2) The eight rosewood samples can be distinctly divided into eight categories by principal component analysis (PCA), the differences in the NIR among the eight rosewood species were more distinctly revealed by the three-dimensional PCA score plot than that of the two-dimensional. The results illustrated that it was feasible to identify rosewood species by near infrared spectroscopy coupled with chemometrics, and also provided a new method to rapidly identify or classify rosewood.


Asunto(s)
Espectroscopía Infrarroja Corta , Madera/análisis , Análisis de Componente Principal
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