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1.
Nano Lett ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38722094

RESUMO

Diamond is considered the most promising next-generation semiconductor material due to its excellent physical characteristics. It has been more than three decades since the discovery of a special structure named n-diamond. However, despite extensive efforts, its crystallographic structure and properties are still unclear. Here, we show that subdisordered structures in diamond provide an explanation for the structural feature of n-diamond. Monocrystalline diamond with subdisordered structures is synthesized via the chemical vapor deposition method. Atomic-resolution scanning transmission electron microscopy characterizations combined with the picometer-precision peak finder technology and diffraction simulations reveal that picometer-scale shifts of atoms within cells of diamond govern the subdisordered structures. First-principles calculations indicate that the bandgap of diamond decreases rapidly with increasing shifting distance, in accordance with experimental results. These findings clarify the crystallographic structure and electronic properties of n-diamond and provide new insights into the bandgap adjustment in diamond.

2.
Plant Cell ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38723594

RESUMO

Grain size and weight are crucial yield-related traits in rice (Oryza sativa). Although certain key genes associated with rice grain size and weight have been successfully cloned, the molecular mechanisms underlying grain size and weight regulation remain elusive. Here, we identified a molecular pathway regulating grain size and weight in rice involving the MPS ONE BINDER KINASE ACTIVATOR-LIKE 1A-SERINE/THREONINE-PROTEIN KINASE 38-CYCLIN C (OsMOB1A-OsSTK38-OsCycC) module. OsSTK38 is a nuclear Dbf2-related kinase that positively regulates grain size and weight by coordinating cell proliferation and expansion in the spikelet hull. OsMOB1A interacts with and enhances the autophosphorylation of OsSTK38. Specifically, the critical role of the OsSTK38 S322 site in its kinase activity is highlighted. Furthermore, OsCycC, a component of the Mediator complex, was identified as a substrate of OsSTK38, with enhancement by OsMOB1A. Notably, OsSTK38 phosphorylates the T33 site of OsCycC. The phosphorylation of OsCycC by OsSTK38 influenced its interaction with the transcription factor KNOTTED-LIKE HOMEOBOX OF ARABIDOPSIS THALIANA 7 (OsKNAT7). Genetic analysis confirmed that OsMOB1A, OsSTK38 and OsCycC function in a common pathway to regulate grain size and weight. Taken together, our findings revealed a connection between the Hippo signalling pathway and the Cyclin-Dependent Kinase (CDK) module in eukaryotes. Moreover, they provide insights into the molecular mechanisms linked to yield-related traits and propose innovative breeding strategies for high-yielding varieties.

3.
Food Chem ; 447: 138997, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38513493

RESUMO

Herein we developed a multicolor lateral flow immunoassay (LFIA) test strip for rapid and simultaneous quantitative detection of aflatoxin B1 (AFB1) and zearalenone (ZEN). Three differently colored aggregation-induced emission nanoparticles (AIENPs) were designed as LFIA signal tags, with red and green AIENPs for targeting AFB1 and ZEN at the test line, and yellow AIENPs for indicating the validity of the test strip at the control (C) line. After surface functionalization with antibodies, the developed AIENP-based multicolor LFIA allows simultaneous and accurate quantification of AFB1 and ZEN using an independent C-line assisted ratiometric signal output strategy. The detection limits of AFB1 and ZEN were 6.12 and 26 pg/mL, respectively. The potential of this method for real-world applications was well demonstrated in corn and wheat. Overall, this multicolor LFIA shows great potential for field screening of multiple mycotoxins and can be extended to rapid and simultaneous monitoring of other small molecule targets.


Assuntos
Nanopartículas Metálicas , Micotoxinas , Zearalenona , Zearalenona/análise , Aflatoxina B1/análise , Anticorpos Monoclonais , Micotoxinas/análise , Imunoensaio/métodos , Limite de Detecção , Contaminação de Alimentos/análise
4.
Small Methods ; : e2301288, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38054606

RESUMO

Gallium oxide (Ga2 O3 ) usually fractures in the brittle form, and achieving large plastic deformability to avoid catastrophic failure is in high demand. Here, ε-Ga2 O3 thin films with columnar crystals and partial unoccupied Ga sites are synthesized, and it is demonstrated that the ε-Ga2 O3 at the submicron scale can be compressed to an ultra-large plastic strain of 48.5% without cracking. The compressive behavior and related mechanisms are investigated by in situ transmission electron microscope nanomechanical testing combined with atomic-resolution characterizations. The serrated plastic flow and large strain burst are two major deformation forms of ε-Ga2 O3 during compression, which are attributed to the dislocation nucleation and avalanches, formation of new grains, and amorphization. The ultra-large compressive plasticity of ε-Ga2 O3 thin films at the submicron scale can inspire new applications of Ga2 O3 in micro- or nano- electronic and optoelectronic devices, especially those that require impact resistance during processing or service.

5.
Environ Sci Technol ; 57(49): 20905-20914, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38010209

RESUMO

NOx storage-reduction (NSR), a promising approach for removing NOx pollutants from diesel vehicles, remains elusive to cope with the increasingly lower exhaust temperatures (especially below 250 °C). Here, we develop a conceptual electrified NSR strategy, where electricity with a low input power (0.5-4 W) is applied to conductive Pt and K co-supported antimony-doped tin oxides (Pt-K/ATO), with C3H6 as a reductant. The ignition temperature for 10% NOx conversion is nearly 100 °C lower than that of the traditional thermal counterpart. Furthermore, reducing the power in the fuel-lean period relative to that in the fuel-rich period increases the maximum energy efficiency by 23%. Electrically driven release of lattice oxygen is revealed to play vital roles in multiple steps in NSR, including NO adsorption, desorption, and reduction, for improved NSR activity. This work provides an electrification strategy for developing high-activity NSR catalysis utilizing electricity onboard hybrid vehicles.


Assuntos
Poluentes Atmosféricos , Óxidos de Nitrogênio , Óxidos de Nitrogênio/análise , Temperatura , Estanho , Antimônio , Óxidos , Emissões de Veículos/análise , Catálise , Poluentes Atmosféricos/análise
6.
New Phytol ; 240(3): 1066-1081, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37574840

RESUMO

Modifications of plant architecture can increase planting density, regulate photosynthesis, and improve crop yields. Many basic helix-loop-helix (bHLH) transcription factors participate in the brassinosteroid (BR) signaling pathway and are critical for plant architecture morphogenesis in rice. However, the number of identified bHLH genes suitable for improving production value is still limited. In this study, we cloned Lam1, encoding the typical bHLH transcription factor OsbHLH92. OsbHLH92 knockout (KO) lines exhibit erect leaves. Decreases in the number and size of parenchyma cell layers on the adaxial side of the lamina joint in KO lines were the main reason for the decreased leaf angle. Genetic experiments verify that OsBU1 and its homologs are downstream of OsbHLH92, which is involved in the noncanonical RGA1-mediated BR signaling pathway. OsbHLH91, an OsbHLH92 homolog, plays both conserved and differentiated roles relative to OsbHLH92. Notably, OsbHLH92-KO lines show erect leaves without the acquisition of adverse agronomic traits. Moreover, by driving a specific panicle promoter, OsbHLH92 can greatly increase productivity by at least 10%. This study identifies new components of the BR signaling pathway, demonstrates the importance of OsbHLH92 in improving planting density and crop productivity, and broadens our knowledge of typical and atypical bHLH family members in rice.

7.
ACS Omega ; 8(26): 23840-23850, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37426267

RESUMO

Seven deflagration tests of a propane-air mixture were carried out in a 22.5 m3 large-scale chamber. The effects of initial volume, gas concentration, and initial turbulence intensity on deflagration characteristics were analyzed. The main frequency of the explosion wave was quantitatively determined by the combination of the wavelet transform and energy spectrum analysis. The results show that the explosive overpressure is formed by the discharge of combustion products and secondary combustion, and the effects of turbulence and gas concentration on the explosive overpressure are higher than the initial volume. Under the condition of weak initial turbulence, the main frequency of gas explosion wave is between 32.13 and 48.33 Hz. Under strong initial turbulence conditions, the main frequency of the gas explosion wave increases with the increase of overpressure, and the empirical formula of the relationship between the main frequency and overpressure is summarized, which could provide theoretical support for the design of mechanical metamaterials for oil and gas explosion. Finally, the flame acceleration simulator numerical model was calibrated through tests, and the overpressure simulation values were in good agreement with the experimental data. The leakage, diffusion, and explosion of a liquefied hydrocarbon loading station in a petrochemical enterprise were simulated. The lethal distance and explosion overpressure at key buildings are predicted for different wind speed conditions. The simulation results can provide a technical basis for evaluating personnel injury and building damage.

9.
J Clin Med ; 12(8)2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37109241

RESUMO

BACKGROUND: How to obtain a donor liver remains an open issue, especially in the choice of minimally invasive donors right hepatectomy versus open donors right hepatectomy (MIDRH versus ODRH). We conducted a meta-analysis to clarify this question. METHODS: A meta-analysis was performed in PubMed, Web of Science, EMBASE, Cochrane Central Register, and ClinicalTrials.gov databases. Baseline characteristics and perioperative outcomes were analyzed. RESULTS: A total of 24 retrospective studies were identified. For MIDRH vs. ODRH, the operative time was longer in the MIDRH group (mean difference [MD] = 30.77 min; p = 0.006). MIDRH resulted in significantly less intraoperative blood loss (MD = -57.86 mL; p < 0.00001), shorter length of stay (MD = -1.22 days; p < 0.00001), lower pulmonary (OR = 0.55; p = 0.002) and wound complications (OR = 0.45; p = 0.0007), lower overall complications (OR = 0.79; p = 0.02), and less self-infused morphine consumption (MD = -0.06 days; 95% CI, -1.16 to -0.05; p = 0.03). In the subgroup analysis, similar results were observed in pure laparoscopic donor right hepatectomy (PLDRH) and the propensity score matching group. In addition, there were no significant differences in post-operation liver injury, bile duct complications, Clavien-Dindo ≥ 3 III, readmission, reoperation, and postoperative transfusion between the MIDRH and ODRH groups. DISCUSSION: We concluded that MIDRH is a safe and feasible alternative to ODRH for living donators, especially in the PLDRH group.

10.
Science ; 379(6637): 1130-1135, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36927013

RESUMO

Intercalated layered materials offer distinctive properties and serve as precursors for important two-dimensional (2D) materials. However, intercalation of non-van der Waals structures, which can expand the family of 2D materials, is difficult. We report a structural editing protocol for layered carbides (MAX phases) and their 2D derivatives (MXenes). Gap-opening and species-intercalating stages were respectively mediated by chemical scissors and intercalants, which created a large family of MAX phases with unconventional elements and structures, as well as MXenes with versatile terminals. The removal of terminals in MXenes with metal scissors and then the stitching of 2D carbide nanosheets with atom intercalation leads to the reconstruction of MAX phases and a family of metal-intercalated 2D carbides, both of which may drive advances in fields ranging from energy to printed electronics.

11.
Anal Chim Acta ; 1247: 340869, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36781245

RESUMO

Organic fluorescein dye-embedded fluorescent microspheres (FMs) are currently the most established commercially fluorescent markers, and they have been widely used to improve the sensitivity of immunochromatography assay (ICA). However, these FMs have natural defects, such as the aggregation-caused quenching effect and small Stokes shift, which are not conducive to improving the detection performance of ICA. Herein, two green emitted FMs, namely aggregation-induced emission FMs (AIEFMs) and fluorescein isothiocyanate FMs (FITCFMs), were prepared by swelling the AIE luminogens and FITC dyes into the carboxyl group-modified polystyrene microspheres. The average diameters of AIEFMs and FITCFMs were 350 and 450 nm, respectively. Compared with FITCFMs, the AIEFMs exhibited stronger fluorescence intensity and a larger Stokes shift. These two FMs were used as the labeling markers of ICA for procalcitonin (PCT) detection with the sandwich format. Among them, AIEFM-ICA showed dynamic linear detection of PCT from 7.6 pg mL-1 to 125 ng mL-1 with the limit of detection (LOD) at 3.8 pg mL-1. These values were remarkably superior to those of FITCFM-ICA (linear range from 61 pg mL-1 to 62.5 ng mL-1 and LOD value at 60 pg mL-1). Furthermore, the average recoveries of the intra- and inter-assays of AIEFM-ICA ranged from 86% to 112%, with coefficients of variation ranging from 1.2% to 8.8%, indicating accuracy and precision for PCT quantitative detection. Additionally, the reliability of the developed AIEFM-ICA was further assessed by analyzing 30 real serum samples from systemic inflammatory response by infectious diseases, and the results showed good agreement with the chemiluminescence immunoassay. In conclusion, compared with traditional FITCFMs, green emitted AIEFMs as a novel fluorescent label, exhibits greater potential to enhance the detection performance of the ICA platform.


Assuntos
Corantes , Luminescência , Microesferas , Reprodutibilidade dos Testes , Cromatografia de Afinidade/métodos , Fluoresceínas , Imunoensaio/métodos
12.
Food Chem ; 412: 135580, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-36736185

RESUMO

Herein, we report a novel aggregation-induced emission nanoparticles (AIENPs)-based immunochromatography assay (ICA) platform to detect ochratoxin A (OTA) using orange-yellow-emitting AIENPs as fluorescent nanoprobes. Immunochromatographic strip is used for the quantitative detection of OTA in crop matrix using AIENPs coupled with anti-OTA ascites. Under optimal conditions, AIENPs-ICA exhibits stronger signal output capacity and higher sensitivity than traditional gold nanoparticles-based ICA. The half-maximal inhibitory concentration is as low as 0.149 ng mL-1, and the limit detection is 0.042 ng mL-1 at 10 % competitive inhibition concentration. The average recovery of AIENPs-ICA ranges from 82.60 % to 113.14 % with the coefficient of variation ranging from 1.26 % to 11.57 %, proving the proposed method possesses good reliability and reproducibility. Moreover, the developed AIENPs-ICA exhibits negligible cross-reactions with other mycotoxins. We believe the presented AIENPs-ICA platform holds promising potential as a powerful tool for on-site detection of OTA and other molecules detection in food samples.


Assuntos
Nanopartículas Metálicas , Ocratoxinas , Ouro/química , Zea mays/química , Reprodutibilidade dos Testes , Cromatografia de Afinidade/métodos , Limite de Detecção , Nanopartículas Metálicas/química , Ocratoxinas/análise
13.
Toxins (Basel) ; 15(1)2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36668898

RESUMO

Lateral flow immunoassay (LFIA) based on fluorescent microbeads has attracted much attention for its use in rapid and accurate food safety monitoring. However, conventional fluorescent microbeads are limited by the aggregation-caused quenching effect of the loaded fluorophores, thus resulting in low signal intensity and insufficient sensitivity of fluorescent LFIA. In this study, a green-emitting fluorophore with an aggregation-induced emission (AIE) characteristic was encapsulated in polymer nanoparticles via an emulsification technique to form ultrabright fluorescent microbeads (denoted as AIEMBs). The prepared AIEMBs were then applied in a competitive LFIA (AIE-LFIA) as signal reporters for the rapid and highly sensitive screening of fumonisin B1 (FB1) in real corn samples. High sensitivity with a detection limit of 0.024 ng/mL for FB1 was achieved by the developed AIE-LFIA. Excellent selectivity, good accuracy, and high reliability of the AIE-LFIA were demonstrated, indicating a promising platform for FB1 screening.


Assuntos
Ouro , Nanopartículas Metálicas , Reprodutibilidade dos Testes , Microesferas , Imunoensaio/métodos , Limite de Detecção
14.
Plant Cell Environ ; 46(2): 363-378, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36444099

RESUMO

Photosynthesis is a process that uses solar energy to fix CO2 in the air and converts it into sugar, and ultimately powers almost all life activities on the earth. C3 photosynthesis is the most common form of photosynthesis in crops. Current efforts of increasing crop yields in response to growing global food requirement are mostly focused on improving C3 photosynthesis. In this review, we summarized the strategies of C3 photosynthesis improvement in terms of Rubisco properties and photorespiratory limitation. Potential engineered targets include Rubisco subunits and their catalytic sites, Rubisco assembly chaperones, and Rubisco activase. In addition, we reviewed multiple photorespiratory bypasses built by strategies of synthetic biology to reduce the release of CO2 and ammonia and minimize energy consumption by photorespiration. The potential strategies are suggested to enhance C3 photosynthesis and boost crop production.


Assuntos
Fenômenos Bioquímicos , Ribulose-Bifosfato Carboxilase , Ribulose-Bifosfato Carboxilase/metabolismo , Dióxido de Carbono , Fotossíntese/fisiologia , Produtos Agrícolas/fisiologia
15.
Biosci Biotechnol Biochem ; 86(11): 1552-1561, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36073357

RESUMO

Garlic is a popular culinary herb for the prevention and treatment of alcoholic liver disease (ALD). Diallyl Trisulfide (DATS) is the major organosulfur compound of garlic. Latest studies indicated that the hepatocyte pyroptosis serves a primary role in the pathogenesis of ALD. The present study aims to assess the inhibitory effect of DATS on alcohol-induced hepatocyte pyroptosis, and to elucidate the potential mechanism by using the hepatocyte cell line HL-7702. Our study found that DATS inhibited alcohol-induced pyroptosis by decreasing gasdermin D (GSDMD) activation. Results illuminated that DATS inhibited alcohol-induced (NOD)-like receptor containing pyrin domain 3 (NLRP3) inflammasome activation by reducing intracellular reactive oxygen species (ROS) accumulation. Furthermore, DATS upregulated hydrogen sulfide (H2S) to resist ROS overproduction. The present study demonstrated that DATS mitigated alcohol-induced hepatocyte pyroptosis by increasing the intracellular level of H2S.


Assuntos
Compostos Alílicos , Alho , Sulfeto de Hidrogênio , Sulfeto de Hidrogênio/farmacologia , Sulfeto de Hidrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Piroptose , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Apoptose , Compostos Alílicos/farmacologia , Sulfetos/farmacologia , Hepatócitos/metabolismo , Etanol , Antioxidantes/farmacologia
16.
Biomacromolecules ; 23(6): 2562-2571, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35561014

RESUMO

Insect cuticle is a fiber-reinforced composite material that consists of polysaccharide chitin fibers and a protein matrix. The molecular interactions between insect cuticle proteins and chitin that govern the assembly and evolution of cuticles are still not well understood. Herein, we report that Ostrinia furnacalis cuticular protein hypothetical-1 (OfCPH-1), a newly discovered and most abundant cuticular protein from Asian corn borer O. furnacalis, can form coacervates in the presence of chitosan. The OfCPH-1-chitosan coacervate microdroplets are initially liquid-like but become gel-like with increasing time or salt concentration. The liquid-to-gel transition is driven by hydrogen-bonding interactions, during which an induced ß-sheet structure of OfCPH-1 is observed. Given the abundance of OfCPH-1 in the cuticle of O. furnacalis, this liquid-liquid phase separation process and its aging behavior could play critical roles in the formation of the cuticle.


Assuntos
Quitosana , Mariposas , Animais , Quitina/química , Proteínas de Insetos/química , Insetos , Mariposas/metabolismo
17.
Adv Sci (Weinh) ; 9(18): e2104780, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35474450

RESUMO

Carbonaceous materials are considered strong candidates as anode materials for sodium-ion batteries (SIBs), which are expected to play an indispensable role in the carbon-neutral era. Herein, novel braided porous carbon fibres (BPCFs) are prepared using the chemical vapour deposition (CVD) method. The BPCFs possess interwoven porous structures and abundant vacancies. The growth mechanism of the BPCFs can be attributed to the polycrystalline transformation of the nanoporous copper catalyst in the early stage of CVD process. Density functional theory calculations suggest that the Na+ adsorption energies of the mono-vacancy edges of the BPCFs (-1.22 and -1.09 eV) are lower than that of an ideal graphene layer (-0.68 eV), clarifying in detail the adsorption-dominated sodium storage mechanism. Hence, the BPCFs as an anode material present an outstanding discharge capacity of 401 mAh g-1 at 0.1 A g-1 after 500 cycles. Remarkably, this BPCFs anode, under high-mass-loading of 5 mg cm-2, shows excellent long-term cycling ability with a reversible capacity of 201 mAh g-1 at 10 A g-1 over 1000 cycles. This study provided a novel strategy for the development of high-performance carbonaceous materials for SIBs.

18.
Am J Orthod Dentofacial Orthop ; 161(3): 404-415.e1, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35115200

RESUMO

INTRODUCTION: Unilateral condylar hyperplasia (UCH) is a progressive, nonneoplastic overgrowth of the condyle of the temporomandibular joint. For treating active UCH, a popular method combines orthognathic surgery with high condylectomy and orthodontic treatment. The goal of this study was to introduce a new method to correct asymmetry for active UCH. METHODS: Retrospectively, 47 patients with active UCH were divided into horizontal-type, vertical-type, and combined-type. All patients were treated with condylectomy plus postsurgery standard orthodontics (CPSO) with applied miniscrews implanted in infrazygomatic crest and hard palate to intrude affected side of maxillary molars and apply intermaxillary traction for contralateral molars. Cone-beam computed tomography was taken at presurgery, postsurgery, and the end of orthodontics (T3). RESULTS: In the vertical (n = 10) and combined (n = 28) types, deviation of the chin and the canting of the mandible and maxillary occlusal plane were significantly reduced at T3. A difference in the torque of bilateral maxillary first molar (U6) and bilateral mandibular first molar (L6) was significantly reduced at T3. The anterior, superior, and posterior joint spaces in the vertical-type and combined-type were significantly decreased at T3 compared with postsurgery. In contrast, in the horizontal-type group (n = 9), the deviation of the chin was corrected; however, the canting of the mandible and maxillary occlusal plane was significantly increased at T3 compared with presurgery. CONCLUSIONS: CPSO restored facial and occlusal symmetry for vertical-type and combined-type active UCH and returned affected-side condyle to the glenoid fossa. However, CPSO was not suitable for treating the horizontal-type UCH.


Assuntos
Assimetria Facial , Côndilo Mandibular , Assimetria Facial/diagnóstico por imagem , Assimetria Facial/cirurgia , Humanos , Hiperplasia/diagnóstico por imagem , Hiperplasia/patologia , Hiperplasia/cirurgia , Mandíbula , Côndilo Mandibular/diagnóstico por imagem , Côndilo Mandibular/patologia , Côndilo Mandibular/cirurgia , Estudos Retrospectivos
19.
Plant J ; 109(3): 523-540, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34750914

RESUMO

The translocation of photosynthate carbohydrates, such as sucrose, is critical for plant growth and crop yield. Previous studies have revealed that sugar transporters, plasmodesmata and sieve plates act as important controllers in sucrose loading into and unloading from phloem in the vascular system. However, other pivotal steps for the regulation of sucrose movement remain largely elusive. In this study, characterization of two starch excesses in mesophyll (sem) mutants and dye and sucrose export assays were performed to provide insights into the regulatory networks that drive source-sink relations in rice. Map-based cloning identified two allelic mutations in a gene encoding a GLUCAN SYNTHASE-LIKE (GSL) protein, thus indicating a role for SEM1 in callose biosynthesis. Subcellular localization in rice showed that SEM1 localized to the plasma membrane. In situ expression analysis and GUS staining showed that SEM1 was mainly expressed in vascular phloem cells. Reduced sucrose transport was found in the sem1-1/1-2 mutant, which led to excessive starch accumulation in source leaves and inhibited photosynthesis. Paraffin section and transmission electron microscopy experiments revealed that less-developed vascular cells (VCs) in sem1-1/1-2 potentially disturbed sugar movement. Moreover, dye and sugar trafficking experiments revealed that aberrant VC development was the main reason for the pleiotropic phenotype of sem1-1/1-2. In total, efficient sucrose loading into the phloem benefits from an optional number of VCs with a large vacuole that could act as a buffer holding tank for sucrose passing from the vascular bundle sheath.


Assuntos
Transporte Biológico/genética , Células do Mesofilo/metabolismo , Oryza/genética , Oryza/fisiologia , Floema/metabolismo , Amido/genética , Amido/metabolismo , Açúcares/metabolismo , Transporte Biológico/fisiologia , Produtos Agrícolas/genética , Produtos Agrícolas/fisiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas
20.
J Hazard Mater ; 424(Pt A): 127402, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34879585

RESUMO

The macro- and micro-physical properties of cement-stabilized steel slag (CSS) base materials in a highway project were studied. A discrete element model of CSS with a real steel slag shape was constructed using Particle Flow Code 3D and 3D scanning technology. The sensitivity between the macro- and micro-parameters of the sample was explored, and a nonlinear regression equation was established to analyze the relationship between these parameters. Uniaxial compression simulation tests were conducted on CSS with steel slag contents of 0%, 10%, 30%, and 50%. By combining contact calculation, crack location, energy tracking, acoustic emission (AE) monitoring, and other program systems, the macro- and micro-mechanical properties and micro-crack evolution law of the samples in the failure process were analyzed in terms of strength, energy, and fracture damage. The damage mechanism of CSS was also revealed. Results showed that with the increase in steel slag content, the elastic modulus and peak stress of the samples increased, the Poisson's ratio decreased, and the post-peak stress curve steepened, indicating obvious brittle failure characteristics. With the increase in steel slag content, the crack initiation stress, thickness of the fracture surface, and number of internal micro-cracks in CSS increased exponentially. In the uniaxial compression test, AE intensity underwent five stages, in which the peak moment of AE intensity exhibited hysteresis compared with the moment of the peak stress. Absorption and release phenomena of strain energy were observed in the process of specimen failure. When the steel slag content increased, the total strain energy absorbed by the specimen increased. When the absorbed energy exceeded the bond strength, the bond ruptured with the release of energy. The main crack of the sample penetrated and stretched to the direction of strain energy release to form a macroscopic fracture surface.

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