Transcriptome analysis of Gossypium reveals the molecular mechanisms of Ca2+ signaling pathway on arsenic tolerance induced by arbuscular mycorrhizal fungi

IntroductionArbuscular mycorrhizal fungi (AMF) have been demonstrated their ability to enhance the arsenic (As) tolerance of host plants, and making the utilization of mycorrhizal plants a promising and practical approach for remediating As-contaminated soils. However, comprehensive transcriptome analysis to reveal the molecular mechanism of As tolerance in the symbiotic process between AMF and host plants is still limited.MethodsIn this study, transcriptomic analysis of Gossypium seedlings was conducted with four treatments: non-inoculated Gossypium under non-As stress (CK0), non-inoculated Gossypium under As stress (CK100), F. mosseae-inoculated Gossypium under non-As stress (FM0), and F. mosseae-inoculated Gossypium under As stress (FM100).ResultsOur results showed that inoculation with F. mosseae led to a reduction in net fluxes of Ca2+, while increasing Ca2+ contents in the roots and leaves of Gossypium under the same As level in soil. Notably, 199 and 3129 differentially expressed genes (DEGs) were specially regulated by F. mosseae inoculation under As stress and non-As stress, respectively. Through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation and enrichment analyses, we found that under As stress, F. mosseae inoculation up-regulated a significant number of genes related to the Ca2+ signaling pathway genes, involved in cellular process, membrane part, and signal transduction. This suggests a potential role in mitigating As tolerance in Gossypium seedlings. Furthermore, our analysis identified specific DEGs in transcription factor families, including ERF, MYB, NAC, and WRKY, that were upregulated by F. mosseae inoculation. Conversely, MYB and HB-other were down-regulated. The ERF and MYB families exhibited the highest number of up- and down-regulated DEGs, respectively, which were speculated to play an important role in alleviating the As toxicity of Gossypium.DiscussionOur findings provided valuable insights into the molecular theoretical basis of the Ca2+ signaling pathway in improving As tolerance of mycorrhizal plants in the future

Distinct Topological Surface States on the Two Terminations of MnBi4_4Te7_7

The recent discovered intrinsic magnetic topological insulator MnBi2Te4 have been met with unusual success in hosting emergent phenomena such as the quantum anomalous Hall effect and the axion insulator states. However, the surface-bulk correspondence of the Mn-Bi-Te family, composed by the superlattice-like MnBi2Te4/(Bi2Te3)n (n = 0, 1, 2, 3 ...) layered structure, remains intriguing but elusive. Here, by using scanning tunneling microscopy (STM) and angle-resolved photoemission spectroscopy (ARPES) techniques, we unambiguously assign the two distinct surface states of MnBi4Te7 (n = 1) to the quintuple-layer (QL) Bi2Te3 termination and the septuple-layer (SL) MnBi2Te4 termination, respectively. A comparison of the experimental observations with theoretical calculations reveals the diverging topological behaviors, especially the hybridization effect between magnetic and nonmagnetic layers, on the two terminations: a gap on the QL termination originating from the topological surface states of the QL hybridizing with the bands of the beneath SL, and a gapless Dirac-cone band structure on the SL termination with time-reversal symmetry. The quasi-particle interference patterns further confirm the topological nature of the surface states for both terminations, continuing far above the Fermi energy. The QL termination carries a spin-helical Dirac state with hexagonal warping, while at the SL termination, a strongly canted helical state from the surface lies between a pair of Rashba-split states from its neighboring layer. Our work elucidates an unprecedented hybridization effect between the building blocks of the topological surface states, and also reveals the termination-dependent time-reversal symmetry breaking in a magnetic topological insulator, rendering an ideal platform to realize the half-integer quantum Hall effect and relevant quantum phenomena.Comment: 22 Pages, 4 Figure

Widening fracturing potential in different kinds of oilfields

The old oilfields in our factory have entered the period of high water cut, the target of fracturing has changed from the main layer to the non-main layer, and the main layers have been fractured again and again. We have difficulty in choosing proper layers because good layers are in high-water-cut and there are not enough emerge in poor layers. As the oil quality of new oilfields deteriorates gradually, the effect of the fracturing gets worse and the effective period is short. The fracturing potential is gradually reducing. In this paper, according to the characteristics of different oilfields, the focus of potential exploitation will be shifted to the high aquifer where the remaining oil is enriched and thin differential layer in old oilfields, The new oilfields will carry out fracturing reconstruction corresponding to oil and water wells to shorten the displacement distance. By constantly quantifying and optimizing the principle of well selection and layer selection, perfecting the adjustment mode, optimizing the fracturing technology and scale, and taking the “three development”, the fracturing potential is further released. The effect of the fracturing is guaranteed, and the development of the oilfield is improved

Electrolyte-gated organic field-effect transistors based on organic semiconductor: insulating polymer blends

La presente tesis doctoral se centra en la fabricación, optimización, caracterización y aplicación de capas activas compuestas de una mezcla de semiconductor orgánico y un polímero aislante (OSC:PS) en transistores orgánicos de efecto de campo (EGOFET) con puerta-electrolítica. El EGOFET esta considerado como una prometedora plataforma de detección en el campo de la bioelectrónica debido a su capacidad de operar en medios electrolíticos. Hasta la fecha, aunque en varios proyectos de investigación se ha demostrado su alto potencial como plataforma de detección, existe algunos problemas que deben resolverse, tales como su baja movilidad del portador de carga, lentos tiempo de respuesta y una degradación rápida que dificultan su aplicación práctica. En este contexto, la tesis se divide en tres bloques, que van desde la fabricación de los dispositivos hasta sus aplicaciones. La primera parte de la tesis tiene como objetivo la fabricación de dispositivo robustos y eficientes empleando dos estrategias: (i) la optimización de la mezclas de polímero aislante y semiconductor orgánico (OSC) y (ii) el uso de una técnica basada en la deposición de capas activas mediante disolución que recibe el nombre de BAMS (bar assistance meniscus shearing). En la primera parte de la tesis (Capitulo 2), se emplearon cuatro semiconductores orgánicos diferentes en que se incluyen tres pequeñas moléculas y un polímero semiconductor como materiales activos. Los dispositivos se han caracterizado mediante medida electricas (características de transferencia y salida) y su analisis y compresión, la sensibilidad potenciométrica, velocidad de conmutación (tiempo de respuesta) y estabilidad eléctrica en agua MilliQ y soluciones salinas (NaCl). Además, la segunda parte de la tesis (Capítulo 3) está dedicada al desarrollo de un sensor de iones de mercurio basado la exposición de los capas activas a disoluciones acuosa que contienen iones de mercurio. En este caso, se observó un cambio gradual en el potencial umbral, que era respuesta directa de la concentración de iones a la qual se exponia la capa activa. Además, se realizaron pruebas de microscopía de fuerza de atómica “Kelvin-prove” y espectroscopía electroquímica de impedancia con el objetivó de entender el mecanismo de respuesta frente al mercurio. El cual se relaciono con la oxidación/reducción de los iones Hg2+ y la superficie del semiconductor. Finalmente, la tercera parte de la tesis (Capítulo 4) se centra en la fabricación de nuevos dispositivo sustituyendo el electrolito por un hidrogel (HYGOFET). Logrando dispositivo de alto rendimiento empleando un hidrogel a base de agua como dieléctrico. Además, el HYGOFET muestra una excelente respuesta a los variación de presión debida a la alineación de los dipolos del agua dentro de la capa de semiconductor. Por lo tanto, el dispositivo se puede visualizar como un prototipo de sensor de presión adaptable a ropa inteligente.The present Doctoral Thesis is focused on the fabrication, optimization, characterization and application of organic semiconductors:insulating polymer blends for electrolyte-gated organic field-effect transistors (EGOFETs), which are considered a promising sensing platform in the field of bioelectronics due to their ability to operate in common electrolyte media. Up to date, although several research works have already demonstrated the high potential of using EGOFETs as sensing platform, some unsolved problems (i.e. low carrier mobility, slow response time and fast degradation) are actually hindering their practical application. Within this context, the thesis is divided into three main parts, from EGOFET devices fabrication to their applications. The first part of the thesis aims to obtain robust and efficient EGOFETs device based on two overlooked strategies: (i) the exploitation of blends composed by an insulating polymer and an organic semiconductor (OSC) and (ii) the use of a solution-shearing technique, such as bar-assisted meniscus shearing (BAMS), to deposit the OSC:PS blend. In this part (Chapter 2), four OSCs, including three small molecules and one polymer, were selected as active materials for the fabrication of EGOFETs. The four OSC:polymer blends EGOFET devices have been systematically studied by evaluating and comparing their transfer and output characteristics, potentiometric sensitivity, switching speed and their electrical stability properties recorded in MilliQ water and a NaCl solution as electrolyte media. In addition, the second part of the thesis (Chapter 3) is devoted to the development of a mercury ions sensor based on an EGOFETs by systematically exposing the blend films to a mercury ions aqueous solutions. In this case, a gradual positive threshold voltage shift of the electrical characteristics was observed, which was selected as the detection parameter towards mercury ions. Furthermore, Kelvin probe force microscopy and electrochemical impedance spectroscopy tests were carried out to explore the mechanism of the mercury response, which was demonstrated to be related to the redox reaction between Hg2+ ions and the semiconductor surface. Finally, the third part of the thesis (Chapter 4) is focused on the fabrication of a novel EGOFET device, namely a hydrogel-gated organic field-effect transistor (HYGOFET). A high performance HYGOFET device was achieved by replacing the liquid electrolyte with a water-based hydrogel to serve as dielectric layer. Furthermore, the HYGOFET exhibits an excellent response to pressure stimuli due to the alignment of water dipoles within the OSC layer. The device can thus be envisioned as proof of concept device which can be find applications in the field of textile electronic skin

High performing solution-coated electrolyte-gated organic fieldeffect transistors for aqueous media operation

Since the first demonstration, the electrolyte-gated organic field-effect transistors (EGOFETs) have immediately gained much attention for the development of cutting-edge technology and they are expected to have a strong impact in the field of (bio-)sensors. However EGOFETs directly expose their active material towards the aqueous media, hence a limited library of organic semiconductors is actually suitable. By using two mostly unexplored strategies in EGOFETs such as blended materials together with a printing technique, we have successfully widened this library. Our benchmarks were 6,13-bis(triisopropylsilylethynyl)pentacene and 2,8-difluoro-5,11-bis(triethylsilylethynyl) anthradithiophene (diF-TES-ADT), which have been firstly blended with polystyrene and secondly deposited by means of the bar-assisted meniscus shearing (BAMS) technique. Our approach yielded thin films (i.e. no thicker than 30 nm) suitable for organic electronics and stable in liquid environment. Up to date, these EGOFETs show unprecedented performances. Furthermore, an extremely harsh environment, like NaCl 1M, has been used in order to test the limit of operability of these electronic devices. Albeit an electrical worsening is observed, our devices can operate under different electrical stresses within the time frame of hours up to a week. In conclusion, our approach turns out to be a powerful tool for the EGOFET manufacturing.The authors thank the ERC StG 2012–306826 e-GAMES project, the Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), the DGI (Spain) project BE-WELL CTQ2013-40480-R, the Generalitat de Catalunya (2014-SGR-17) and the Spanish Ministry of Economy and Competitiveness, through the ‘Severo Ochoa’ Programme for Centres of Excellence in R&D (SEV- 2015-0496). Q. Z. acknowledges the China Scholarship Council, the National Natural Science Foundation (NSF) of China (Grant No. 11404266) and the Fundamental Research Funds for the Central Universities of China (Grant No. XDJK2014C081). Q. Z. And I. T. are enrolled in the Materials Science PhD Program of Universitat Autònoma de Barcelona. F.L. gratefully acknowledges the “Juan de la Cierva” programme. The research leading to these results has received funding from the People Programme (Marie Curie Actions) of the Seventh Framework Programme of the European Union (FP7/2007–2013) under REA grant agreement no.600388 (TECNIOSpring programme), and from the Agency for Business Competitiveness of the Government of Catalonia, ACCIÓ. The authors thank Dr. D. Gutierrez and Dr. S. Galindo for their assistance with the switching speed measurements.Peer reviewe