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The 2LiF-BeF2 (FLiBe) salt melt is considered the primary choice for a coolant and fuel carrier for the generation IV molten salt reactor (MSR). However, the basics of ionic coordination and short-range ordered structures have been rarely reported due to the toxicity and volatility of beryllium fluorides, as well as the lack of suitable high-temperature in situ probe methods. In this work, the local structure of FLiBe melts was investigated in detail using the newly designed HT-NMR method. It was found that the local structure was comprised of a series of tetrahedral coordinated ionic clusters (e.g., BeF42-, Be2F73-, Be3F104-, and polymeric intermediate-range units). Li+ ions were coordinated by BeF42- ions and the polymeric Be-F network through the analysis of the NMR chemical shifts. Using solid-state NMR, the structure of solid FLiBe solidified mixed salts was confirmed to form a 3D network structure, significantly similar to those of silicates. The above results provide new insights into the local structure of FLiBe salts, which verifies the strong covalent interactions of Be-F coordination and the specific structural transformation to the polymeric ions above 25% BeF2 concentration.
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Inter-tissue communication is instrumental to coordinating the whole-body level behaviour for complex multicellular organisms. However, little is known about the regulation of inter-tissue information exchange. Here we carried out genetic screens for root-to-shoot mobile silencing in Arabidopsis plants with a compromised small RNA-mediated gene silencing movement rate and identified radical-induced cell death 1 (RCD1) as a critical regulator of root-shoot communication. RCD1 belongs to a family of poly (ADP-ribose) polymerase proteins, which are highly conserved across land plants. We found that RCD1 coordinates symplastic and apoplastic movement by modulating the sterol level of lipid rafts. The higher superoxide production in rcd1-knockout plants resulted in lower plasmodesmata (PD) frequency and altered PD structure in the symplasm of the hypocotyl cortex. Furthermore, the mutants showed increased lateral area of tracheary pits, which reduced axial movement. Our study highlights a novel mechanism through which root-to-shoot long-distance signalling can be modulated both symplastically and apoplastically.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas Nucleares/metabolismo , Raíces de Plantas/metabolismo , Poli(ADP-Ribosa) Polimerasas/genética , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Root-derived mobile signals play critical roles in coordinating a shoot's response to underground conditions. However, the identification of root-to-shoot long-distance mobile signals has been scant. In this study, we aimed to characterize root-to-shoot endogenous mobile miRNAs by using an Arabidopsis/Nicotiana interfamilial heterograft in which these two taxonomically distant species with clear genetic backgrounds had sufficient diversity in differentiating miRNA sources. Small RNA deep sequencing analysis revealed that 82 miRNAs from the Arabidopsis scion could travel through the graft union to reach the rootstock, whereas only a very small subset of miRNA (6 miRNAs) preferred the root-to-shoot movement. We demonstrated in an ex vivo RNA imaging experiment that the root-to-shoot mobile Nb-miR164, Nb-miR395 and Nb-miR397 were targeted to plasmodesmata using the bacteriophage coat protein MS2 system. Furthermore, the Nb-miR164 was shown to move from the roots to the shoots to induce phenotypic changes when its overexpressing line was used as rootstock, strongly supporting that root-derived Nb-miR164 was able to modify the scion trait via its long-distance movement.
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Regulación de la Expresión Génica de las Plantas , MicroARNs/genética , Nicotiana/genética , Raíces de Plantas/genética , Brotes de la Planta/genética , ARN de Planta/genética , Raíces de Plantas/crecimiento & desarrollo , Brotes de la Planta/crecimiento & desarrollo , Nicotiana/crecimiento & desarrolloRESUMEN
A series of rigid nonconjugated polyimide (PI)-based thermally activated delayed fluorescence (TADF) polymers were reported for the first time, based on a "TADF-Linker-Host" strategy. Among of which, the TADF unit contains a typical TADF luminous core structure, the "Host" unit exhibits effective conjugation length that endows polyimide with high triplet energy, and the "Linker" unit has an aliphatic ring structure to improve solubility and inhibits intramolecular charge transfer effect. All the TADF polymers exhibit high thermal stability (Tg >308.7 °C) and refractive index (1.76-1.79). Remarkably, highly-efficient polymer light-emitting diodes (PLEDs) based on the polymers are successfully realized, leading to a maximal external quantum efficiency of 21.0 % along with low efficiency roll-off. Such outstanding efficiency is amongst the state-of-the-art performance of nonconjugated PLEDs, confirming the effectiveness of structural design strategy, providing helpful and valuable guidance on the development of highly-efficient fluorescent polymer materials and PLEDs.
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Soft luminescent materials are attractive for optoelectronic applications, however, switching dominant chromophores for property enrichment remains a challenge. Herein, we report the first case of a soft organic molecule (DOS) featuring selective expression of chromophores. In response to various external stimuli, different chromophores of DOS can take turns working through conformation changes, exhibiting full-colour emissions peaking from 469â nm to 583â nm from ten individual single crystals. Dynamic triplet-exciton behaviours including thermally activated delayed fluorescence (TADF), room-temperature phosphorescence (RTP), mechanoluminescence (ML), and distinct mechano-responsive luminescence (MRL) can all be realized. This novel designed DOS molecule provides a multifunctional platform for detection of volatile organic compounds (VOCs), multicolour dynamic displays, sensing, anticounterfeiting, and hopefully many others.
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The Love wave biosensor is considered to be one of the most promising probing methods in biomedical research and diagnosis, and has been applied to detect the mechano-biological behaviour of cells attached to the surface of the device. More efforts should be devoted to basic theoretical research and relevant device performance analysis that may contribute to the further developments of Love wave sensors. In this study, a 36º YX-LiTaO3-based Love wave sensor with a parylene-C wave guiding layer was adopted as a cell-based biosensor to monitor the adhesion process of tendon stem/progenitor cells (TSCs), a newly discovered cell type in tendons. A theoretical model is proposed to describe the Love wave propagation, in which the adherent cells are considered as a uniform viscoelastic layer. The effects of viscoelastic cell layer and wave guiding layer on the propagation velocity υ and propagation loss (PL) are investigated. The numerical results indicate that adherent cell layers of different storage or loss shear modulus in certain ranges can induce pronounced and characteristic variations in υ and PL, revealing the potential of Love wave sensors to provide useful quantitative measures on cellular mechanical properties. The sensor response to the adhesion of TSCs exhibits high consistency with experimental observations, which demonstrates the Love wave biosensor as a very promising sensor platform for investigating cellular activities under multiple physiological conditions.
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Acústica , Técnicas Biosensibles/métodos , Adhesión Celular , Células Madre/citología , Tendones/citología , Elasticidad , ViscosidadRESUMEN
In this study, quartz thickness-shear mode (TSM) resonator sensors were adopted to monitor the process of platelet activation. Resting platelets adhering to fibrinogen-coated electrodes were activated by different concentrations of thrombin (1, 10, and 100 U/mL), and the corresponding electrical admittance spectra of TSM resonators during this process were recorded. Based on a bilayer-loading transmission line model of TSM resonators, the complex shear modulus (G' + jGâ³) and the average thickness (hPL) of the platelet monolayer at a series of time points were obtained. Decrease in thrombin concentration from 100 to 1 U/mL shifted all peaks and plateaus in G', Gâ³, and hPL to higher time points, which could be attributed to the partial activation of platelets by low concentrations of thrombin. The peak value of hPL was acquired when platelets presented their typical spherical shape as the first transformation in activation process. The G' peak appeared 10 â¼ 20 min after hPL peak, when some filopods were observed along the periphery of platelets but without obvious cell spreading. As platelet spreading began and continued, G', Gâ³, and hPL decreased, leading to a steady rise of resonance frequency shift of TSM resonator sensors. The results show high reliability and stability of TSM resonator sensors in monitoring the process of platelet activation, revealing an effective method to measure platelet activities in real-time under multiple experimental conditions. The G', Gâ³, and hPL values could provide useful quantitative measures on platelet structure variations in activation process, indicating potential of TSM resonators in characterization of cells during their transformation.
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Técnicas Biosensibles/métodos , Activación Plaquetaria , Animales , Técnicas Biosensibles/instrumentación , Electrodos , Cuarzo/química , Ratas , Trombina/químicaRESUMEN
Aims: Evaluating the association between a single nucleotide polymorphism in the 3' untranslated region (3'UTR) of the miRNA binding site of the NLRP3 gene and the occurrence and development of chronic obstructive pulmonary disease (COPD) and providing information to aid in the early detection and treatment of COPD. Materials and Methods: The regulatory single nuclear polymorphisms (SNPs) located in NLRP3 3'UTR were searched by using the dbSNP database and miRNA binding site prediction database. Meanwhile, samples from COPD patients and healthy controls in the same period were used for verification. The clinical baseline information of all subjects was collected, and the transcription level and protein expression level of NLRP3 and the expression level of inflammatory factors downstream of NLRP3 were detected. The effects of SNPs' single nucleotide changes on the transcription and expression of inflammatory factors were analyzed. Results: The study included 418 participants (249 in the COPD group and 169 in the control group). NLRP3 SNPs with miRNA binding sites include rs10754558 (G > C), rs1664774076 (ATAT > del), and rs1664775106 (C > G). Furthermore, two genotypes, GCG and GCA, were discovered to have a linkage mutation at 3'UTR 459-461. COPD susceptibility is tightly associated with the expression of the rs1664774076 del/del genotype, and the risk of COPD increased by 2.770 times (p = 0.003). Type 459-461 GCA was substantially related to the likelihood of developing COPD at various stages (p < 0.05). Except for rs10754558, all homozygous mutants increased NLRP3 mRNA and protein levels. NLRP3 had the greatest area under the receiver operating characteristic (ROC) curve for predicting the development and diagnosis of COPD when compared with its downstream inflammatory variables (AUC = 0.9291). Conclusions: The NLRP3 rs1664774076 del/del genotype is a COPD susceptibility gene, and the GCA genotype at 459-461 can be used as an early predictor of COPD exacerbation. The NLRP3 3'UTR polymorphism may alter the loss of miRNA binding sites, leading to an increase in NLRP3 expression. In the development of COPD, NLRP3 has a better diagnostic value than traditional inflammatory factors. The Clinical Trials Registration number Z: protocol KY01-2020-11-06.
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Regiones no Traducidas 3' , Predisposición Genética a la Enfermedad , MicroARNs , Proteína con Dominio Pirina 3 de la Familia NLR , Polimorfismo de Nucleótido Simple , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/genética , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Regiones no Traducidas 3'/genética , Polimorfismo de Nucleótido Simple/genética , Predisposición Genética a la Enfermedad/genética , Femenino , Masculino , Persona de Mediana Edad , Anciano , Estudios de Casos y Controles , Sitios de Unión/genética , Genotipo , Factores de Riesgo , AlelosRESUMEN
Monitoring endogenous glutathione (GSH) levels in living cells is essential for cancer diagnose and treatment. In this work, GSH responsive fluorescent nanoprobe with turn-on property was constructed using Zn-modified porphyrinic metal-organic frameworks (PCN-224-Zn). The introduced Zn2+ could quench the fluorescence of PCN-224 by the metallization of organic ligand (TCPP) and serves as sensing site for GSH. When exposed to GSH, the strong binding affinity of GSH generates the formation of Zn-GSH complex, eliminating the fluorescence quenching effect of Zn2+. Based on the constructed PCN-224-Zn nanoprobe, selective determination of GSH was achieved in the range of 0.01-6 µM with a detection limit of 1.5 nM. Furthermore, the constructed nanoprobe can realize the fluorescence imaging of endogenous GSH in MCF-7 and HeLa cells. Meanwhile, PCN-224-Zn could also monitor GSH in cell lysate with recovery rates from 93.8 % to 102.3 %. The performance of PCN-224-Zn demonstrates its capacities in the application of fluorescence sensing and bio-imaging fields.
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Colorantes , Puntos Cuánticos , Humanos , Células HeLa , Glutatión/metabolismo , Puntos Cuánticos/química , Zinc/química , Colorantes Fluorescentes/toxicidad , Colorantes Fluorescentes/químicaRESUMEN
Introduction: Prostate Cancer (PCa) remains a significant concern in male cancer-related mortality. Tumour development is intricately regulated by the complex interactions between tumour cells and their microenvironment, making it essential to determine which is/are key factor(s) that influence the progression of PCa within the tumour microenvironment. Materials and methods: The current study utilised histopathology and immunohistochemistry to determine the expression of IL-38 in PCa and analysed the correlation between the expression level of IL-38 within PCa and clinical pathological characteristics. Results: There was a significant increase in IL-38 expression in PCa tissues compared to adjacent non-PCa tissues (P < 0.0001). In addition, IL-38 expression was significantly higher in tumour cells with a high proliferation index compared to those with a low value-added index. ROC curve analysis demonstrated that IL-38 has high specificity and sensitivity for the diagnosis of PCa (AUC=0.76). Moreover, we Probed the cellular source of IL-38 in prostate cancer tissue by immunofluorescence double staining. Additionally, within PCa, the expression of IL-38 was inversely correlated with the expression levels of CD8 and PD-1. Survival analysis revealed a significantly lower overall survival rate for PCa patients with high IL-38 expression (P=0.0069), and when IL-38 was co-expressed with CD8, the survival rate of the IL-38high/CD8low group was decreased significantly. Multivariate analysis indicated that the expression level of IL-38 and TNM staging were independent predictors of survival in PCa patients. Conclusion: These findings suggest that IL-38 plays a crucial role in the development of PCa, and the exploration of the correlation between IL-38 and various immune factors in the tumour microenvironment further reveals its mechanism of action, making it a potential target for immunotherapy in PCa.
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Interleucinas , Neoplasias de la Próstata , Anciano , Humanos , Masculino , Persona de Mediana Edad , Biomarcadores de Tumor , Interleucinas/metabolismo , Pronóstico , Receptor de Muerte Celular Programada 1/metabolismo , Receptor de Muerte Celular Programada 1/genética , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/metabolismo , Microambiente Tumoral/inmunologíaRESUMEN
Introduction: Wound healing poses a clinical challenge in diabetes mellitus (DM) due to compromised host immunity. CD64, an IgG-binding Fcgr1 receptor, acts as a pro-inflammatory mediator. While its presence has been identified in various inflammatory diseases, its specific role in wound healing, especially in DM, remains unclear. Objectives: We aimed to investigate the involvement of CD64 in diabetic wound healing using a DM animal model with CD64 KO mice. Methods: First, we compared CD64 expression in chronic skin ulcers from human DM and non-DM skin. Then, we monitored wound healing in a DM mouse model over 10 days, with or without CD64 KO, using macroscopic and microscopic observations, as well as immunohistochemistry. Results: CD64 expression was significantly upregulated (1.25-fold) in chronic ulcerative skin from DM patients compared to non-DM individuals. Clinical observations were consistent with animal model findings, showing a significant delay in wound healing, particularly by day 7, in CD64 KO mice compared to WT mice. Additionally, infiltrating CD163+ M2 macrophages in the wounds of DM mice decreased significantly compared to non-DM mice over time. Delayed wound healing in DM CD64 KO mice correlated with the presence of inflammatory mediators. Conclusion: CD64 seems to play a crucial role in wound healing, especially in DM conditions, where it is associated with CD163+ M2 macrophage infiltration. These data suggest that CD64 relies on host immunity during the wound healing process. Such data may provide useful information for both basic scientists and clinicians to deal with diabetic chronic wound healing.
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Diabetes Mellitus Experimental , Úlcera Cutánea , Cicatrización de Heridas , Animales , Ratones , Diabetes Mellitus Experimental/metabolismo , Modelos Animales de Enfermedad , Macrófagos/metabolismo , Piel/metabolismo , Cicatrización de Heridas/genéticaRESUMEN
BACKGROUND: Hearing loss (HL) is the most frequent sensory deficit in humans, with strong genetic heterogeneity. The genetic diagnosis of HL is very important to aid treatment decisions and to provide prognostic information and genetic counselling for the patient's family. METHODS: We detected and analysed 362 Chinese non-syndromic HL patients by screening of variants in 15 hot spot mutations. Subsequently, 40 patients underwent further whole-exome sequencing (WES) to determine genetic aetiology. The candidate variants were verified using Sanger sequencing. Twenty-three carrier couples with pathogenic variants or likely pathogenic variants chose to proceed with prenatal diagnosis using Sanger sequencing. RESULTS: Among the 362 HL patients, 102 were assigned a molecular diagnosis with 52 different variants in 22 deafness genes. A total of 41 (11.33%) cases with the biallelic GJB2 (OMIM # 220290) gene mutations were detected, and 21 (5.80%) had biallelic SLC26A4 (OMIM # 605646) mutations. Mitochondrial gene (OMIM # 561000) mutations were detected in seven (1.93%) patients. Twenty of the variants in 15 deafness genes were novel. SOX10 (OMIM # 602229), MYO15A (OMIM # 602666) and WFS1 (OMIM # 606201) were each detected in two patients. Meanwhile, OSBPL2 (OMIM # 606731), RRM2B (OMIM # 604712), OTOG (OMIM # 604487), STRC (OMIM # 606440), PCDH15 (OMIM # 605514), LOXHD1 (OMIM # 613072), CDH23 (OMIM # 605516), TMC1 (OMIM # 606706), CHD7 (OMIM # 608892), DIAPH3 (OMIM # 614567), TBC1D24 (OMIM # 613577), TIMM8A (OMIM # 300356), PTPRQ (OMIM # 603317), SALL1 (OMIM # 602218), and GSDME (OMIM # 608798) were each detected in one patient. In addition, as regards one couple with a heterozygous variant of CDH23 and PCDH15, respectively, prenatal diagnosis results suggest that the foetus had double heterozygous (DH) variants of CDH23 and PCDH15, which has a high risk to cause ID/F type Usher syndrome. CONCLUSION: Our study expanded the spectrum of deafness gene variation, which will contribute to the genetic diagnosis, prenatal diagnosis and the procreation guidance of deaf couple. In addition, the deafness caused by two genes should be paid attention to in the prenatal diagnosis of families with both deaf patients.
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Mutación , Humanos , Femenino , Masculino , China , Niño , Pérdida Auditiva/genética , Adulto , Preescolar , Transportadores de Sulfato/genética , Adolescente , Proteínas Relacionadas con las CadherinasRESUMEN
Molten NaF-BeF2 salt is widely considered a promising candidate to replace FLiBe in molten salt reactor applications, which is crucial to reducing the operating costs of the molten salt reactor. Studies on beryllium compounds are rarely conducted due to their volatility and high toxicity. Herein, the Be-F coordination structure of NaF/BeF2 mixed salts was investigated in-depth through various HT-NMR and solid-state NMR methods, which are optimized to be appropriate for the detection of beryllium compounds. It was found that Na2BeF4 and NaBeF3 crystals were transformed into amorphous tetrahedral coordinated networks when there was an increase in the BeF2 concentration in the mixed salts. The main coordinate structure comparisons between FNaBe and FLiBe were analyzed, which exhibit high similarity due to the covalent effect of Be-F bonding, demonstrating the theoretical feasibility of applying FNaBe salts as a substitute for FLiBe in MSR systems. In addition, the transition from the crystal phase to the amorphous phase occurred at a lower BeF2 concentration for FNaBe than that for FLiBe. This was further verified by the results of ab initio molecular dynamics (AIMD) simulation that FNaBe melts had more disordered structures, thus causing slight changes in their physical properties.
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Hybridized local and charge-transfer (HLCT) emitters have attracted extensive attention, but the insolubility and severe self-aggregation tendency restrict their applications in solution-processable organic light-emitting diodes (OLEDs), particularly deep-blue OLEDs. Herein, two novel benzoxazole-based solution-processable HLCT emitters (BPCP and BPCPCHY) are designed and synthesized, in which benzoxazole acts as an acceptor, carbazole acts as a donor, and hexahydrophthalimido (HP, with a large intramolecular torsion angle and spatial distortion characteristics) acts as a bulky modified end-group with weak electron-withdrawing effects. Both BPCP and BPCPCHY exhibit HLCT characteristics and emit near ultraviolet in toluene at 404 and 399 nm. Compared to the BPCP, the BPCPCHY solid shows much better thermal stability (Tg, 187 vs 110 °C), higher oscillator strengths of the S1-to-S0 transition (0.5346 vs 0.4809), and faster kr (1.1 × 108 vs 7.5 × 107 s-1) and thus a much higher ΦPL in the neat film. The introduction of HP groups greatly suppresses the intra-/intermolecular charge-transfer effect and self-aggregation trends, and the BPCPCHY neat films placed in air for 3 months can still maintain an excellent amorphous morphology. The solution-processable deep-blue OLEDs utilizing BPCP and BPCPCHY achieved a CIEy of 0.06 with maximum external quantum efficiency (EQEmax) values of 7.19 and 8.53%, respectively, which are among the best results of the solution-processable deep-blue OLEDs based on the "hot exciton" mechanism. All of the above results indicate that benzoxazole is an excellent acceptor for constructing deep-blue HLCT materials, and the strategy of introducing HP as a modified end-group into an HLCT emitter provides a new perspective to develop solution-processable efficient deep-blue OLEDs with high morphological stability.
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In distantly-related plant grafting, incompatibility often occurs between scion and rootstock, resulting in growth stagnation, and eventually graft failure. In this study, we found that an emergent structure, or the spiraling tracheary element (TE) bundles consisting of TE masses occurring at the graft interface, was extensively present in the highly incompatible interfamilial graft of Brassica napus/Portulaca oleracea (Bn/Po) and Nicotiana benthamiana/Portulaca oleracea (Nb/Po). This special structure mostly appeared in the local area near the grafting union, and the frequency and quantity of the spiraling tracheary element bundles were much higher in the scion than in the rootstock. Nevertheless, only a small portion of Arabidopsis thaliana/Portulaca oleracea (At/Po) interfamilial grafts showed a less spiraled TEs at the grafting union (usually a circular TE), which is consistent with its growth performance. This study consolidated that spiraling TE bundles were an important indicator for graft incompatibility. The possible reason for the formation of spiraling TE bundles in interfamilial grafts was discussed.
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Arabidopsis , Brassica napusRESUMEN
Vascular connection is key to successful graft. Little study has been devoted to the behavior of tracheary elements (TEs), the basic component of vascular bundles, during vascular connection between scion and rootstock. Here we report the structural changes of TEs at the graft interface between two quinoa cultivars, Qaidam White-1 (QW1) and Qaidam Red-1 (QR1). Our results showed that TEs in ungrafted plants developed following an ontogenetic sequence, i.e., the annular vessel, helical vessel, scalariform vessel, reticulate vessel, and pitted vessel. However, this process was greatly accelerated in grafted plants, resulting in quick developmental transition of TE wall patterning. At the early stage of intraspecific grafting (e.g., 5 days after grafting), the membrane-like cellular patches were heavily accumulated at the graft interface but quickly retreated within 2-4 days, suggesting an early emergency response to grafting. The TE length in both scion and rootstock was significantly shorter (more than 50% on average, nTE = 747) than the ungrafted plants in the same period. These short TEs were gradually integrated into a long, continuous conduit, thereby enabling the functional vasculature at the graft union. In addition, the pit size was gradually reduced, for example, for the surface area of outer pit aperture, from 12.73 ± 3.15 to 5.40 ± 0.30 µm2, or for the surface area of inner pit aperture, from 9.34 ± 3.33 to 1.96 ± 1.04 µm2, in 18 days (npits = 2830). Taken together, the morphological changes of TEs and cellular responses to grafting in the intraspecific grafts seemed to be conservative to other homografts and heterografts, implying that these behavioral changes are highly adaptive to the scion-rootstock interaction.
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Chenopodium quinoa , PlantasRESUMEN
Three-Dimentional (3-D) printing is currently a popular printing technique that is used in many sectors. Potentially, this technology is expected to replace conventional manufacturing in the coming years. It is accelerating in gaining attention due to its design freedom where objects can be produced without imagination boundaries. The review presents a perspective on the application of 3-D printing application based on various fields. However, the ordinary 3-D printed products with a single type of raw often lack robustness leading to broken parts. Improving the mechanical property of a 3-D printed part is crucial for its applications in many fields. One of the promising solutions is to incorporate nanoparticles or fillers into the raw material. The review aims to provide information about the types of additive manufacturing. There are few types of raw materials can be used as foundation template in the printing, enhanced properties of the printed polymer nanocomposites with different types of nanoparticles as additives in the printing. The article reviews the advantages and disadvantages of different materials that are used as raw materials or base materials in 3-D printing. This can be a guideline for the readers to compare and analyse the raw materials prior to a decision on the type of material to be selected. The review prepares an overview for the researchers to choose the types of nanoparticles to be added in the printing of the products depending on the targeted application. With the added functionality of the 3-D polymer nanocomposites, it will help in widespread of the application of 3-D printing technology in various sector.
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Scion-rootstock union formation is a critical step toward the functional assemblage of heterogeneous plants. Interfamilial scion-rootstock interaction often results in graft incompatibility during the assemblage process, and the underlying mechanisms are largely unknown. In this study, we reported that tracheary element (TE) remodeling, including TE segmentation and deformation, rather than de novo formation from callus or adjacent tissues, took place at the early stage of grafting interface between Arabidopsis thaliana and Nicotiana benthamiana (At/Nb). Following cellular deposits, the short TEs from both partners were overlapping, dependent on the homogeneity of contacting TEs, with each other. Without overlapping, the TEs at the interface would grow laterally, and the TEs above and below the interface would undergo self-fusion to form insulating spiraling bundles. Finally, the overlapping TEs constituted a continuous network through alignment. Our results provide a definitive framework for the critical process of TE behavior in the At/Nb distant grafts, including (1) segmentation and/or deformation, (2) matching, overlapping, and cellular deposits, and (3) aligning or spiraling. These insights might guide us in the future into constructing more compatible distant grafts from the perspective of TE homogeneity.
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ABSTRACT: To investigate the mental health status of obstetric nurses and its influencing factors during the novel coronavirus epidemic period, so as to provide theoretical reference for hospital decision-makers and managers.From February 25 to March 20, 2020, we conducted a cross-sectional survey through online questionnaire, and selected obstetric nurses from Jilin and Heilongjiang Provinces as the research objects by convenience sampling.Three hundred eighteen valid questionnaires were collected; the results of Symptom Checklist 90 showed that the scores of "obsessive-compulsive", "depression", "anxiety", "hostility", "phobia", and "psychosis" were higher than the Chinese norm (Pâ<â.01). There were 107 people whose total score of Symptom Checklist 90 was more than 160, and 83 people whose number of positive items was more than 43. Logistic regression results showed that married, temporary employment, lack of support and communication from family and relatives, onerous task, and unbearable responsibility were independent risk factors for mental disorder.There is a great psychological burden for obstetric nurses during the epidemic period. Decision makers should focus on necessary psychological intervention for those that are married, temporarily employed, and those lacking family supports including communication. At the same time, managers should distribute tasks reasonably to avoid psychological burdens caused by overwork.
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COVID-19/psicología , Salud Mental/estadística & datos numéricos , Enfermeras Obstetrices/psicología , Enfermería Obstétrica , Pandemias , Ansiedad/epidemiología , COVID-19/epidemiología , China/epidemiología , Estudios Transversales , Depresión/epidemiología , Estado de Salud , Humanos , SARS-CoV-2 , Encuestas y CuestionariosRESUMEN
The occurrence of pelvic floor dysfunctional disease (PFD) is closely related with elasticity, toughness, and functional changes of the connective tissue of the pelvic support tissue. Bone marrow mesenchymal stem cells (BMSCs) have been confirmed to have the capacity to differentiate into a variety of cell types such as osteoblasts, chondroblasts, adipocytes and fibroblasts. Therefore, BMSCs have the potential to improve the clinical outcomes for PFD. Peroxisome proliferator-activated receptor-γ (PPAR-γ), a ligand activated transcription factor, has acquired a great deal of attention as it is involved in the fibrosis and cell differentiation. However, how it is regulated during the process of the differentiation of BMSCs into fibroblasts remains to be defined. The present study investigated the underlying mechanisms of PPAR-γ effect of mechanical stretch on the differentiation of BMSCs induced by pelvic ligament fibroblasts. PPAR-γ expression was decreased during the differentiation of BMSCs into fibroblasts by co-cultured stretched fibroblasts. Addition of transforming growth factor-ß1 (TGF-ß1) reduced PPAR-γ expression and promoted the differentiation of BMSCs. With the employment of endogenous ligand, activation of PPAR-γ suppressed the BMSC differentiation. Similar effects were also observed with overexpression of PPAR-γ gene. In addition, decrease of PPAR-γ by the use of shRNA targeting rat PPAR-γ significantly contributed to BMSC differentiation to fibroblasts. These results indicate that PPAR-γ negatively regulates the differentiation of BMSCs into fibroblasts.