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1.
Nat Nanotechnol ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710879
2.
Sci Rep ; 14(1): 10857, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740848

RESUMO

The qRT-PCR technique has been regarded as an important tool for assessing gene expression diversity. Selection of appropriate reference genes is essential for validating deviation and obtaining reliable and accurate results. Lotus (Nelumbo nucifera Gaertn) is a common aquatic plant with important aesthetic, commercial, and cultural values. Twelve candidate genes, which are typically used as reference genes for qRT-PCR in other plants, were selected for this study. These candidate reference genes were cloned with, specific primers designed based on published sequences. In particular, the expression level of each gene was examined in different tissues and growth stages of Lotus. Notably, the expression stability of these candidate genes was assessed using the software programs geNorm and NormFinder. As a result, the most efficient reference genes for rootstock expansion were TBP and UBQ. In addition, TBP and EF-1α were the most efficient reference genes in various floral tissues, while ACT and GAPDH were the most stable genes at all developmental stages of the seed. CYP and GAPDH were the best reference genes at different stages of leaf development, but TUA was the least stable. Meanwhile, the gene expression profile of NnEXPA was analyzed to confirm the validity of the findings. It was concluded that, TBP and GAPDH were identified as the best reference genes. The results of this study may help researchers to select appropriate reference genes and thus obtain credible results for further quantitative RT-qPCR gene expression analyses in Lotus.


Assuntos
Regulação da Expressão Gênica de Plantas , Genes de Plantas , Nelumbo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase em Tempo Real/normas , Reação em Cadeia da Polimerase em Tempo Real/métodos , Nelumbo/genética , Padrões de Referência , Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/normas , Lotus/genética , Lotus/crescimento & desenvolvimento
3.
PLoS One ; 19(5): e0302940, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38748679

RESUMO

Miscanthus lutarioriparia is a promising energy crop that is used for abandoned mine soil phytoremediation because of its high biomass yield and strong tolerance to heavy metals. However, the biological mechanism of heavy metal resistance is limited, especially for applications in the soil restoration of mining areas. Here, through the investigation of soil cadmium(Cd) in different mining areas and soil potted under Cd stress, the adsorption capacity of Miscanthus lutarioriparia was analyzed. The physiological and transcriptional effects of Cd stress on M. lutarioriparia leaves and roots under hydroponic conditions were analyzed. The results showed that M. lutarioriparia could reduce the Cd content in mining soil by 29.82%. Moreover, different Cd varieties have different Cd adsorption capacities in soils with higher Cd concentration. The highest cadmium concentrations in the aboveground and belowground parts of the plants were 185.65 mg/kg and 186.8 mg/kg, respectively. The total chlorophyll content, superoxide dismutase and catalase activities all showed a trend of increasing first and then decreasing. In total, 24,372 differentially expressed genes were obtained, including 7735 unique to leaves, 7725 unique to roots, and 8912 unique to leaves and roots, which showed differences in gene expression between leaves and roots. These genes were predominantly involved in plant hormone signal transduction, glutathione metabolism, flavonoid biosynthesis, ABC transporters, photosynthesis and the metal ion transport pathway. In addition, the number of upregulated genes was greater than the number of downregulated genes at different stress intervals, which indicated that M. lutarioriparia adapted to Cd stress mainly through positive regulation. These results lay a solid foundation for breeding excellent Cd resistant M. lutarioriparia and other plants. The results also have an important theoretical significance for further understanding the detoxification mechanism of Cd stress and the remediation of heavy metal pollution in mining soil.


Assuntos
Cádmio , Regulação da Expressão Gênica de Plantas , Poaceae , Poluentes do Solo , Cádmio/toxicidade , Cádmio/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Poluentes do Solo/toxicidade , Poluentes do Solo/metabolismo , Poaceae/genética , Poaceae/efeitos dos fármacos , Poaceae/metabolismo , Perfilação da Expressão Gênica , Biodegradação Ambiental , Folhas de Planta/metabolismo , Folhas de Planta/genética , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Transcriptoma , Solo/química , Estresse Fisiológico , Mineração
4.
J Mater Chem C Mater ; 12(18): 6637-6644, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38737516

RESUMO

Donor-acceptor polymeric semiconductors are crucial for state-of-the-art applications, such as electronic skin mimics. The processability, and thus solubility, of these polymers in benign solvents is critical and can be improved through side chain engineering. Nevertheless, the impact of novel side chains on backbone orientation and emerging device properties often remains to be elucidated. Here, we investigate the influence of elongated linear and branched discrete oligodimethylsiloxane (oDMS) side chains on solubility and device performance. Thereto, diketopyrrolopyrrole-thienothiophene polymers are equipped with various oDMS pendants (PDPPTT-Sin) and subsequently phase separated into lamellar domains. The introduction of a branching point in the siloxane significantly enhanced the solubility of the polymer, as a result of increased backbone distortion. Simultaneously, the charge carrier mobility of the polymers decreased by an order of magnitude upon functionalization with long and/or branched siloxanes. This work unveils the intricate balance between processability and device performance in organic semiconductors, which is key for the development of next-generation electronic devices.

5.
Mater Horiz ; 11(14): 3352-3363, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38686501

RESUMO

Controlling the multi-level assembly and morphological properties of conjugated polymers through structural manipulation has contributed significantly to the advancement of organic electronics. In this work, a redox active conjugated polymer, TPT-TT, composed of alternating 1,4-(2-thienyl)-2,5-dialkoxyphenylene (TPT) and thienothiophene (TT) units is reported with non-covalent intramolecular S⋯O and S⋯H-C interactions that induce controlled main-chain planarity and solid-state order. As confirmed by density functional theory (DFT) calculations, these intramolecular interactions influence the main chain conformation, promoting backbone planarization, while still allowing dihedral rotations at higher kinetic energies (higher temperature), and give rise to temperature-dependent aggregation properties. Thermotropic liquid crystalline (LC) behavior is confirmed by cross-polarized optical microscopy (CPOM) and closely correlated with multiple thermal transitions observed by differential scanning calorimetry (DSC). This LC behavior allows us to develop and utilize a thermal annealing treatment that results in thin films with notable long-range order, as shown by grazing-incidence X-ray diffraction (GIXD). Specifically, we identified a first LC phase, ranging from 218 °C to 107 °C, as a nematic phase featuring preferential face-on π-π stacking and edge-on lamellar stacking exhibiting a large extent of disorder and broad orientation distribution. A second LC phase is observed from 107 °C to 48 °C, as a smectic A phase featuring sharp, highly ordered out-of-plane lamellar stacking features and sharp tilted backbone stacking peaks, while the structure of a third LC phase with a transition at 48 °C remains unclear, but resembles that of the solid state at ambient temperature. Furthermore, the significance of thermal annealing is evident in the ∼3-fold enhancement of the electrical conductivity of ferric tosylate-doped annealed films reaching 55 S cm-1. More importantly, thermally annealed TPT-TT films exhibit both a narrow distribution of charge-carrier mobilities (1.4 ± 0.1) × 10-2 cm2 V-1 s-1 along with a remarkable device yield of 100% in an organic field-effect transistor (OFET) configuration. This molecular design approach to obtain highly ordered conjugated polymers in the solid state affords a deeper understanding of how intramolecular interactions and repeat-unit symmetry impact liquid crystallinity, solution aggregation, solution to solid-state transformation, solid-state morphology, and ultimately device applications.

6.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38629931

RESUMO

The long-term monitoring stability of electronic current transformers is crucial for accurately obtaining the current signal of the power grid. However, it is difficult to accurately distinguish between the fluctuation of non-stationary random signals on the primary side of the power grid and the gradual error of the transformers themselves. A current transformer error prediction model, CNN-MHA-BiLSTM, based on the golden jackal optimization (GJO) algorithm, which is used to obtain the optimal parameter values, bidirectional long short-term memory (BiLSTM) network, convolutional neural networks (CNNs), and multi-head attention (MHA), is proposed to address the difficulty of measuring error evaluation. This model can be used to determine the operation of transformers and can be widely applied to assist in determining the stability of transformer operation and early faults. First, CNN is used to mine the vertical detail features of error data at a certain moment, improving the speed of error prediction. Furthermore, a cascaded network with BiLSTM as the core is constructed to extract the horizontal historical features of the error data. The GJO algorithm is used to adjust the parameters of the BiLSTM model; optimize the hidden layer nodes, training frequency, and learning rate; and integrate MHA mechanism to promote the model to pay attention to the characteristic changes of the data in order to improve the accuracy of error prediction. Finally, this method is applied to the operation data of transformer in substations, and four time periods of data are selected to verify the model effectiveness of the current transformer dataset. The analysis results of single step and multi-step examples indicate that the proposed model has significant advantages in terms of accuracy and stability in error prediction.

7.
Nat Mater ; 23(6): 782-789, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38491147

RESUMO

Coupling of spin and charge currents to structural chirality in non-magnetic materials, known as chirality-induced spin selectivity, is promising for application in spintronic devices at room temperature. Although the chirality-induced spin selectivity effect has been identified in various chiral materials, its Onsager reciprocal process, the inverse chirality-induced spin selectivity effect, remains unexplored. Here we report the observation of the inverse chirality-induced spin selectivity effect in chiral assemblies of π-conjugated polymers. Using spin-pumping techniques, the inverse chirality-induced spin selectivity effect enables quantification of the magnitude of the longitudinal spin-to-charge conversion driven by chirality-induced spin selectivity in different chiral polymers. By widely tuning conductivities and supramolecular chiral structures via a printing method, we found a very long spin relaxation time of up to several nanoseconds parallel to the chiral axis. Our demonstration of the inverse chirality-induced spin selectivity effect suggests possibilities for elucidating the puzzling interplay between spin and chirality, and opens a route for spintronic applications using printable chiral assemblies.

8.
Proc Natl Acad Sci U S A ; 121(9): e2313617121, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38377215

RESUMO

Additive manufacturing capable of controlling and dynamically modulating structures down to the nanoscopic scale remains challenging. By marrying additive manufacturing with self-assembly, we develop a UV (ultra-violet)-assisted direct ink write approach for on-the-fly modulation of structural color by programming the assembly kinetics through photo-cross-linking. We design a photo-cross-linkable bottlebrush block copolymer solution as a printing ink that exhibits vibrant structural color (i.e., photonic properties) due to the nanoscopic lamellar structures formed post extrusion. By dynamically modulating UV-light irradiance during printing, we can program the color of the printed material to access a broad spectrum of visible light with a single ink while also creating color gradients not previously possible. We unveil the mechanism of this approach using a combination of coarse-grained simulations, rheological measurements, and structural characterizations. Central to the assembly mechanism is the matching of the cross-linking timescale with the assembly timescale, which leads to kinetic trapping of the assembly process that evolves structural color from blue to red driven by solvent evaporation. This strategy of integrating cross-linking chemistry and out-of-equilibrium processing opens an avenue for spatiotemporal control of self-assembled nanostructures during additive manufacturing.

9.
ACS Cent Sci ; 9(11): 2096-2107, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38033802

RESUMO

Understanding the solution-state aggregate structure and the consequent hierarchical assembly of conjugated polymers is crucial for controlling multiscale morphologies during solid thin-film deposition and the resultant electronic properties. However, it remains challenging to comprehend detailed solution aggregate structures of conjugated polymers, let alone their chiral assembly due to the complex aggregation behavior. Herein, we present solution-state aggregate structures and their impact on hierarchical chiral helical assembly using an achiral diketopyrrolopyrrole-quaterthiophene (DPP-T4) copolymer and its two close structural analogues wherein the bithiophene is functionalized with methyl groups (DPP-T2M2) or fluorine atoms (DPP-T2F2). Combining in-depth small-angle X-ray scattering analysis with various microscopic solution imaging techniques, we find distinct aggregate in each DPP solution: (i) semicrystalline 1D fiber aggregates of DPP-T2F2 with a strongly bound internal structure, (ii) semicrystalline 1D fiber aggregates of DPP-T2M2 with a weakly bound internal structure, and (iii) highly crystalline 2D sheet aggregates of DPP-T4. These nanoscopic aggregates develop into lyotropic chiral helical liquid crystal (LC) mesophases at high solution concentrations. Intriguingly, the dimensionality of solution aggregates largely modulates hierarchical chiral helical pitches across nanoscopic to micrometer scales, with the more rigid 2D sheet aggregate of DPP-T4 creating much larger pitch length than the more flexible 1D fiber aggregates. Combining relatively small helical pitch with long-range order, the striped twist-bent mesophase of DPP-T2F2 composed of highly ordered, more rigid 1D fiber aggregate exhibits an anisotropic dissymmetry factor (g-factor) as high as 0.09. This study can be a prominent addition to our knowledge on a solution-state hierarchical assembly of conjugated polymers and, in particular, chiral helical assembly of achiral organic semiconductors that can catalyze an emerging field of chiral (opto)electronics.

10.
Med Eng Phys ; 120: 104039, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37689513

RESUMO

OBJECTIVE: To determine the reliability of shear-wave elastography (SWE)in assessing the stiffness of the nuchal fascia and the thickness of upper cervical muscles in neutral head posture (NHP) or forward head posture (FHP). METHODS: Sixteen healthy adults (mean age: 21.69 ± 1.01years, 9 females) were included. SWE mode was chosen to measure the nuchal fascia shear modulus and muscle thickness was measured in B-mode. Measurements were collected by two independent investigators on two different days. The intraclass correlation coefficient (ICC) was used to measure the relative reliability, and the standard error of measurement (SEM) were used to measure the absolute reliability. RESULTS: Intra­rater (ICC = 0.63-0.89) and inter-rater (ICC = 00.54-0.82) reliability for the nuchal fascia shear modulus were moderate to excellent. Intra­rater (ICC = 00.64-0.96) and inter-rater (ICC = 00.48-0.86) reliability for upper cervical muscles thickness were moderate to excellent. The SEM percentage oscillated from 3.27% to 13.55%. There were significant differences(P < 0.05) between NHP and FHP on nuchal fascia shear modulus, right side splenius capitis muscle thickness and left side semispinalis capitis muscle thickness, but no significant differences(P > 0.05) were observed between the right and left sides. The upper cervical muscles thickness of males was significantly thicker(P < 0.01) than females while no significant differences were observed (P > 0.05) on the nuchal fascia shear modulus. CONCLUSIONS: Ultrasound-based SWE may be a reliable tool for assessing the stiffness of the nuchal fascia and the thickness of upper cervical muscles in clinical practice. REGISTRATION NUMBER: ChiCTR2200055736.

11.
Genes (Basel) ; 14(8)2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37628565

RESUMO

Combined with the Konjac transcriptome database of our laboratory and internal reference genes commonly used in plants, the eight candidate internal reference genes were screened and detected. They are the 25S ribosomal RNA gene (25S rRNA), 18S ribosomal RNA gene (18S rRNA), actin gene (ACT), glyceraldehyde-3-phosphate dehydrogenase gene (GAPDH), ubiquitin gene (UBQ), ß-tubulin gene (ß-TUB), eukaryotic elongation factor 1-αgene(eEF-1α), and eukaryotic translation initiation factor 4α-1 gene (eIF-4α). The results of GeNorm, Normfinder, and BestKeeper were analyzed comprehensively. The data showed that the expression levels of 25S rRNA, 18S rRNA, and ACT at the reproductive periods, eEF-1α and eIF-4α at the nutritional periods, and eEF-1α, UBQ, and ACT at different leaf developmental periods were stable. These identified and stable internal reference genes will provide the basis for the subsequent molecular biology-related studies of Konjac.


Assuntos
Amorphophallus , RNA Ribossômico 18S , Transcriptoma/genética , Actinas/genética , Bases de Dados Factuais
12.
Nat Commun ; 14(1): 3930, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37402793

RESUMO

Genetic improvement of grain quality is more challenging in hybrid rice than in inbred rice due to additional nonadditive effects such as dominance. Here, we describe a pipeline developed for joint analysis of phenotypes, effects, and generations (JPEG). As a demonstration, we analyze 12 grain quality traits of 113 inbred lines (male parents), five tester lines (female parents), and 565 (113×5) of their hybrids. We sequence the parents for single nucleotide polymorphisms calling and infer the genotypes of the hybrids. Genome-wide association studies with JPEG identify 128 loci associated with at least one of the 12 traits, including 44, 97, and 13 loci with additive effects, dominant effects, and both additive and dominant effects, respectively. These loci together explain more than 30% of the genetic variation in hybrid performance for each of the traits. The JEPG statistical pipeline can help to identify superior crosses for breeding rice hybrids with improved grain quality.


Assuntos
Oryza , Oryza/genética , Estudo de Associação Genômica Ampla , Melhoramento Vegetal , Fenótipo , Genótipo , Grão Comestível/genética
13.
Chem Rev ; 123(13): 8395-8487, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37273196

RESUMO

The assembly of conjugated organic molecules from solution to solid-state plays a critical role in determining the thin film morphology and optoelectronic properties of solution-processed organic electronics and photovoltaics. During evaporative solution processing, π-conjugated systems can assemble via various forms of intermolecular interactions, forming distinct aggregate structures that can drastically tune the charge transport landscape in the solid-state. In blend systems composed of donor polymer and acceptor molecules, assembly of neat materials couples with phase separation and crystallization processes, leading to complex phase transition pathways which govern the blend film morphology. In this review, we provide an in-depth review of molecular assembly processes in neat conjugated polymers and nonfullerene small molecule acceptors and discuss their impact on the thin film morphology and optoelectronic properties. We then shift our focus to blend systems relevant to organic solar cells and discuss the fundamentals of phase transition and highlight how the assembly of neat materials and processing conditions can affect blend morphology and device performance.

14.
Chem Soc Rev ; 52(9): 3098-3169, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37070570

RESUMO

In the last century, molecular crystals functioned predominantly as a means for determining the molecular structures via X-ray diffraction, albeit as the century came to a close the response of molecular crystals to electric, magnetic, and light fields revealed that the physical properties of molecular crystals were as rich as the diversity of molecules themselves. In this century, the mechanical properties of molecular crystals have continued to enhance our understanding of the colligative responses of weakly bound molecules to internal frustration and applied forces. Here, the authors review the main themes of research that have developed in recent decades, prefaced by an overview of the particular considerations that distinguish molecular crystals from traditional materials such as metals and ceramics. Many molecular crystals will deform themselves as they grow under some conditions. Whether they respond to intrinsic stress or external forces or interactions among the fields of growing crystals remains an open question. Photoreactivity in single crystals has been a leading theme in organic solid-state chemistry; however, the focus of research has been traditionally on reaction stereo- and regio-specificity. However, as light-induced chemistry builds stress in crystals anisotropically, all types of motions can be actuated. The correlation between photochemistry and the responses of single crystals-jumping, twisting, fracturing, delaminating, rocking, and rolling-has become a well-defined field of research in its own right: photomechanics. The advancement of our understanding requires theoretical and high-performance computations. Computational crystallography not only supports interpretations of mechanical responses, but predicts the responses itself. This requires the engagement of classical force-field based molecular dynamics simulations, density functional theory-based approaches, and the use of machine learning to divine patterns to which algorithms can be better suited than people. The integration of mechanics with the transport of electrons and photons is considered for practical applications in flexible organic electronics and photonics. Dynamic crystals that respond rapidly and reversibly to heat and light can function as switches and actuators. Progress in identifying efficient shape-shifting crystals is also discussed. Finally, the importance of mechanical properties to milling and tableting of pharmaceuticals in an industry still dominated by active ingredients composed of small molecule crystals is reviewed. A dearth of data on the strength, hardness, Young's modulus, and fracture toughness of molecular crystals underscores the need for refinement of measurement techniques and conceptual tools. The need for benchmark data is emphasized throughout.

15.
Nat Commun ; 14(1): 1304, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36944642

RESUMO

Cooperativity is used by living systems to circumvent energetic and entropic barriers to yield highly efficient molecular processes. Cooperative structural transitions involve the concerted displacement of molecules in a crystalline material, as opposed to typical molecule-by-molecule nucleation and growth mechanisms which often break single crystallinity. Cooperative transitions have acquired much attention for low transition barriers, ultrafast kinetics, and structural reversibility. However, cooperative transitions are rare in molecular crystals and their origin is poorly understood. Crystals of 2-dimensional quinoidal terthiophene (2DQTT-o-B), a high-performance n-type organic semiconductor, demonstrate two distinct thermally activated phase transitions following these mechanisms. Here we show reorientation of the alkyl side chains triggers cooperative behavior, tilting the molecules like dominos. Whereas, nucleation and growth transition is coincident with increasing alkyl chain disorder and driven by forming a biradical state. We establish alkyl chain engineering as integral to rationally controlling these polymorphic behaviors for novel electronic applications.

16.
Front Neurol ; 13: 997913, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36425797

RESUMO

Background: Spasticity is a common motor disorder resulting from upper motor neuron lesions. It has a serious influence on an individual's motor function and daily activity. Repetitive peripheral magnetic stimulation (rPMS) is a non-invasive and painless approach developed for therapeutic intervention in clinical rehabilitation. However, the effectiveness of this intervention on spasticity in patients with spastic paralysis remains uncertain. Objective: This study aimed to investigate the effectiveness of rPMS on spasticity, motor function, and activities of daily living in individuals with spastic paralysis. Methods: PubMed, PEDro, Embase, Cochrane Library, and Web of Science were searched for eligible papers with date up to March 31, 2022. Two independent researchers conducted study screening, data extraction, and methodological quality assessment. RCTs that explored the effects of rPMS on spasticity, motor function, and activities of daily living in patients with spastic paralysis were included for review. The Cochrane collaboration tool was used to assess methodological quality. The cumulative effects of available data were processed for a meta-analysis using Reedman software. Results: Eight studies with 297 participants were included. Most of the studies presented low to moderate risk of bias. Compared with the control group, the results showed that rPMS had a significant effect on spasticity (all spasticity outcomes: standardized mean difference [SMD] = -0.55, 95% confidence interval [CI]: -0.94 to -0.16, I 2 = 40%, and P = 0.006, Modified Ashworth Scale: mean difference [MD] = -0.48, 95% CI: -0.82 to -0.14, I 2 = 0%, and P = 0.006), motor function (Fugl-Meyer Assessment: MD = 4.17, 95% CI: 0.89 to 7.46, I 2 = 28%, and P = 0.01), and activities of daily living (Barthel Index: MD = 5.12, 95% CI: 2.58 to 7.67, I 2 = 0%, and P < 0.0001). No side effect was reported. Conclusion: The meta-analysis demonstrated that the evidence supported rPMS in improving spasticity especially for passive muscle properties evaluated with Modified Ashworth Scale/Ashworth Scale, as well as motor function and daily activity of living in individuals with spastic paralysis. Study registration: The reviewed protocol of this study is registered in the international prospective register of systematic reviews (PROSPERO) (CRD42022322395). Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/#recordDetails, identifier CRD42022322395.

17.
J Food Sci ; 87(9): 4250-4263, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35986703

RESUMO

Lotus (Nelumbo nucifera) is one of the main aquatic vegetables in China. Its seed and rhizome are main edible parts which are rich in starch. Preliminary experiments of starch contents revealed that seed and rhizome expressed great differences in amylose and amylopectin contents. The rhizomes have higher amylopectin content, while the seeds have higher amylose content. In this study, we have estimated 16 varieties of lotus seeds and found that the amylose content of lotus seeds ranged from 30% to 50%, with an average amylose content of 43%, which showed high-amylose content characteristics. Morphological analysis of lotus seed shown that starch rapid accumulated in 20 DAF (day after fertilization) ∼ 26 DAF. Transcriptome of lotus seeds indicated that starch genes played an important role in seed development. Especially in 22 DAF, the genes which controlled amylose synthesis significantly increased, in contrast, the expression of amylopectin-related genes was stable and might limit the synthesis of amylopectin. We further analyzed the expression patterns of 11 key related genes between lotus seeds and rhizomes, and found that the expression of amylose-related genes to were higher in lotus seed, while the expression of genes related to amylopectin synthesis were higher in rhizome. This study provided a comprehensive research of molecular basis for starch in lotus seed and rhizome. Different expression among key genes during starch accumulation might be the principal cause of the differences in starch properties between seed and rhizome. PRACTICAL APPLICATION: Differential expression involved in starch synthesis pathway genes is the main reason for various starch characteristics of seed and rhizome in lotus. High amylose content in lotus seed is a valuable trait for developing functional food.


Assuntos
Nelumbo , Amilopectina , Amilose , Nelumbo/genética , Rizoma/genética , Sementes , Amido/metabolismo
18.
ACS Polym Au ; 2(4): 232-244, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35971423

RESUMO

Bottlebrush polymers are a class of semiflexible, hierarchical macromolecules with unique potential for shape-, architecture-, and composition-based structure-property design. It is now well-established that in dilute to semidilute solution, bottlebrush homopolymers adopt a wormlike conformation, which decreases in extension (persistence length) as the concentration and molecular overlap increase. By comparison, the solution phase self-assembly of bottlebrush diblock copolymers (BBCP) in a good solvent remains poorly understood, despite critical relevance for solution processing of ordered phases and photonic crystals. In this work, we combine small-angle X-ray scattering, coarse-grained simulation, and polymer synthesis to map the equilibrium phase behavior and conformation of a set of large, nearly symmetric PS-b-PLA bottlebrush diblock copolymers in toluene. Three BBCP are synthesized, with side chains of number-averaged molecular weights of 4500 (PS) and 4200 g/mol (PLA) and total backbone degrees of polymerization of 100, 255, and 400 repeat units. The grafting density is one side chain per backbone repeat unit. With increasing concentration in solution, all three polymers progress through a similar structural transition: from dispersed, wormlike chains with concentration-dependent (decreasing) extension, through the onset of disordered PS/PLA compositional fluctuations, to the formation of a long-range ordered lamellar phase. With increasing concentration in the microphase-separated regimes, the domain spacing increases as individual chains partially re-extend due to block immiscibility. Increases in the backbone degree of polymerization lead to changes in the scattering profiles which are consistent with the increased segregation strength. Coarse-grained simulations using an implicit side-chain model are performed, and concentration-dependent self-assembly behavior is qualitatively matched to experiments. Finally, using the polymer with the largest backbone length, we demonstrate that lamellar phases develop a well-defined photonic band gap in solution, which can be tuned across the visible spectrum by varying polymer concentration.

19.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(3): 851-855, 2022 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-35680816

RESUMO

OBJECTIVE: Compared with the method of optical microscopy, to evaluate the accuracy of fragmented red cells(FRC) detection by Sysmex XN-3000. METHODS: A total of 111 samples were collected from patients diagnosed as thrombotic thrombocytopenic purpura, autoimmune disease, hematological disease, malignant tumor and health examination in our hospital from June 2019 to February 2021, including 74 cases in the case group and 37 cases in the healthy control group. All samples were detected by optical microscope and Sysmex XN-3000, respectively. ROC was used to evaluate the detection ability of Sysmex XN-3000 for schistocyte. Bland-Altman method was used to evaluate the consistency of the results of the two methods for detection of schistocyte, and Pearson correlation analysis was conducted for the difference of the results. RESULTS: The area under the ROC curve was 0.890(95% CI: 0.828-0.952, P<0.01). Sysmex XN-3000 count did not quantitatively agree with schistocyte counts by microscopy in the case group(mean of difference:-1.53, 95% limits of agreement: -8.78~5.72). There was a weak positive correlation between platelet count and the difference of analyzer and microscopic results (r=0.32,P<0.05). CONCLUSION: Sysmex XN-3000 can be used as a reference for qualitative determination of schistocyte. However, the sensitivity of Sysmex XN-3000 should be improved. It is still necessary to combine with manual microscopy. The quantitative results are not reliable now and cannot be used as a reference for monitoring the results of schistocyte in clinical patients after treatment.


Assuntos
Neoplasias , Púrpura Trombocitopênica Trombótica , Humanos , Contagem de Plaquetas , Curva ROC , Reprodutibilidade dos Testes
20.
Adv Mater ; 34(32): e2203055, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35724384

RESUMO

Tuning structures of solution-state aggregation and aggregation-mediated assembly pathways of conjugated polymers is crucial for optimizing their solid-state morphology and charge-transport property. However, it remains challenging to unravel and control the exact structures of solution aggregates, let alone to modulate assembly pathways in a controlled fashion. Herein, aggregate structures of an isoindigo-bithiophene-based polymer (PII-2T) are modulated by tuning selectivity of the solvent toward the side chain versus the backbone, which leads to three distinct assembly pathways: direct crystallization from side-chain-associated amorphous aggregates, chiral liquid crystal (LC)-mediated assembly from semicrystalline aggregates with side-chain and backbone stacking, and random agglomeration from backbone-stacked semicrystalline aggregates. Importantly, it is demonstrated that the amorphous solution aggregates, compared with semicrystalline ones, lead to significantly improved alignment and reduced paracrystalline disorder in the solid state due to direct crystallization during the meniscus-guided coating process. Alignment quantified by the dichroic ratio is enhanced by up to 14-fold, and the charge-carrier mobility increases by a maximum of 20-fold in films printed from amorphous aggregates compared to those from semicrystalline aggregates. This work shows that by tuning the precise structure of solution aggregates, the assembly pathways and the resulting thin-film morphology and device properties can be drastically tuned.

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