[Adaptation of Acidianus hospitalis W1 to oligotrophic and acidic hot spring environments].

OBJECTIVE: To study the adaptation of A. hospitalis W1 to oligotrophic and acidic hot spring environments at the whole genome level. METHODS: We annotated the gene functions and constructed metabolic pathways of strain W1 by using different databases, such as NCBI non-redundant database (NRDB), UniProt, Sulfolobus protein database and Kyoto Encyclopedia of Genes and Genomes (KEGG). The metabolic pathways were polished according to the results of comparative genomics. RESULTS: Strain W1 grew autotrophically by fixing CO2 as carbon source through 3-hydroxypropionate/4-hydroxybutyrate or dicarboxylate-4-hydroxybutyrate cycle, and gained energy for growth by oxidation of reduced inorganic sulfur compounds (RISCs). Strain W1 differenced from A. ambivalens because its genome did not possess sulfur-metabolizing genes encoding sulfite: acceptor oxidoreductase, adenosine phosphosulfate reductase, sulfate adenylyl transferase and phosphoadenosine phosphosulfate reductase. Glucose was metabolized by strain W1 through non- phosphorylated Entner-Doudoroff pathway and tricarboxylic acid cycle. In addition, the sugar and amino acids transporters, as well as related hydrolysis enzymes were identified in the genome. These results suggest that strain W1 could also grow facultative autotrophically. Strain W1 cannot use H2 as electron donor due to lack of hydrogenase encoding genes. CONCLUSION: The versatile metabolic patterns afforded A. hospitalis W1 the ability to adapt to oligotrophic and acidic hot spring environments. Furthermore, the unique metabolic features of strain W1 will help to better understand the metabolic diversities of Acidianus.

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

Introduction: Arbuscular 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. Methods: In 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). Results: Our 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. Discussion: Our findings provided valuable insights into the molecular theoretical basis of the Ca2+ signaling pathway in improving As tolerance of mycorrhizal plants in the future.

Photocurrent generation through electron-exciton interaction at the organic semiconductor donor/acceptor interface.

In this work, we report our effort to understand the photocurrent generation that is contributed via electron-exciton interaction at the donor/acceptor interface in organic solar cells (OSCs). Donor/acceptor bi-layer heterojunction OSCs, of the indium tin oxide/copper phthalocyanine (CuPc)/fullerene (C60)/molybdenum oxide/Al type, were employed to study the mechanism of photocurrent generation due to the electron-exciton interaction, where CuPc and C60 are the donor and the acceptor, respectively. It is shown that the electron-exciton interaction and the exciton dissociation processes co-exist at the CuPc/C60 interface in OSCs. Compared to conventional donor/acceptor bi-layer OSCs, the cells with the above configuration enable holes to be extracted at the C60 side while electrons can be collected at the CuPc side, resulting in a photocurrent in the reverse direction. The photocurrent thus observed is contributed to primarily by the charge carriers that are generated by the electron-exciton interaction at the CuPc/C60 interface, while charges derived from the exciton dissociation process also exist at the same interface. The mechanism of photocurrent generation due to electron-exciton interaction in the OSCs is further investigated, and it is manifested by the transient photovoltage characteristics and the external quantum efficiency measurements.

Some neighbors are more interfering: Asymmetric priming by stroke neighbors in Chinese character recognition.

Chinese is a visually complex logographic script that consists of square-shaped characters, with each character composed of strokes. Previous masked priming studies using single-character Chinese stroke neighbors (i.e., visually similar characters differing in only one or two strokes, e.g., /) have shown facilitatory or inhibitory priming effects. We tested whether the mixed pattern of stroke neighbor priming might be an instance of asymmetry in priming that has been observed previously with Japanese kana and Latin alphabets. Specifically, a prime lacking a stroke (or line segment) that is present in the target speeds up the recognition of its stroke neighbor almost as much as the identity prime (e.g., - = -), but not the converse (e.g., - >> -). Two experiments, one using a character match task and the second using lexical decision, showed a robust asymmetry in priming by stroke neighbors. The results suggest that the early letter identification process is similar across script types, as anticipated by the Noisy Channel model, which regards the first stage of visual word recognition as a language-universal perceptual process.

Co-Inoculation with Arbuscular Mycorrhizal Fungi and Dark Septate Endophytes under Drought Stress: Synergistic or Competitive Effects on Maize Growth, Photosynthesis, Root Hydraulic Properties and Aquaporins?

Arbuscular mycorrhizal fungi (AMF) and dark septate fungi (DSE) were simultaneously colonized in the root cells of maize. Single AMF and DSE symbiosis have been proven to improve the drought tolerance of maize. However, the effects of both fungi coexisting in maize roots under drought stress are not yet known. In this study, pot experiments of maize seedlings were conducted through four inoculation treatments (single AMF inoculation of Rhizophagus irregularis, single DSE inoculation of Exophiala pisciphila, co-inoculation of AMF + DSE and non-mycorrhizal inoculation) under well-watered (WW) and drought-stressed (DS) conditions. AMF and DSE colonization status, maize physiology and aquaporin gene expression in maize roots were investigated. The objective of this paper was to evaluate whether AMF and DSE had competitive, independent or synergistic effects on regulating the drought tolerance of maize. When maize seedlings of three inoculation treatments were subjected to drought stress, single AMF inoculation had the highest shoot and root dry weight, plant height, root length, osmotic root hydraulic conductivity and hydrostatic root hydraulic conductivity in maize seedlings. However, co-inoculation of AMF + DSE induced the highest stomatal conductance in maize leaves and the lowest H2O2 and O2•- concentration, membrane electrolyte leakage, intercellular CO2 concentration and gene expression level of ZmPIP1;1, ZmPIP1;2, ZmPIP2;1, ZmPIP2;5 and ZmPIP2;6. In addition, co-inoculation of AMF + DSE also obviously down-regulated the GintAQPF1 and GintAQPF2 expression in R. irregularis compared with single AMF inoculation treatment. Under DS stress, there were competitive relationships between AMF and DSE with regard to regulating mycorrhizal colonization, maize growth, root hydraulic conductivity and the gene expression of aquaporins in R. irregularis, but there were synergistic relationships with regard to regulating membrane electrolyte leakage, oxidative damage, photosynthesis and the aquaporin gene expression of maize seedlings. The obtained results improve our knowledge about how the mechanisms of AMF and DSE coexist, promoting the drought tolerance of host plants.

Universal Flexible Lamination Encapsulation Strategy toward Underwater-Operation Electroluminescence Devices.

A reliable encapsulation technology with scalability and flexibility is urgently needed for electroluminescence devices. Here, we developed a simple, robust, low-cost, and scalable flexible lamination encapsulation strategy with quantum-dot light-emitting diodes (QLEDs) as the model devices. Multilayered Parafilm combining with calcium oxide buffer was used for the lamination encapsulation. We successfully demonstrated that such a Parafilm Lami encapsulation (PLE) not only allowed excellent protection for QLEDs in air but endowed QLED outstanding waterproof performance. As a result, highly efficient and stable flexible waterproof QLEDs were realized based on this PLE, exhibiting maximum external quantum efficiency of ∼8% and long half-luminescence lifetime of over 1.5 h in water. We believe that there are not any obstacles to extending this encapsulation technology to other flexible flat-panel devices, such as organic/perovskite light-emitting diodes.

Interplay between Electrolyte-Gated Organic Field-Effect Transistors and Surfactants: A Surface Aggregation Tool and Protecting Semiconducting Layer.

Molecular surfactants, which are based on a water-insoluble tail and a water-soluble head, are widely employed in many areas, such as surface coatings or for drug delivery, thanks to their capability to form micelles in solution or supramolecular structures at the solid/liquid interface. Electrolyte-gated organic field-effect transistors (EGOFETs) are highly sensitive to changes occurring at their electrolyte/gate electrode and electrolyte/organic semiconductor interfaces, and hence, they have been much explored in biosensing due to their inherent amplification properties. Here, we demonstrate that the EGOFETs and surfactants can provide mutual benefits to each other. EGOFETs can be a simple and complementary tool to study the aggregation behavior of cationic and anionic surfactants at low concentrations on a polarized metal surface. In this way, we have monitored the monolayer formation of cationic and anionic surfactants at the water/electrode interface with p-type and n-type devices, respectively. On the other hand, the operational stability of EGOFETs has been dramatically enhanced, thanks to the formation of a protective layer on top of the organic semiconductor by exposing it to a high concentration of a surfactant solution (above the critical micelle concentration). Stable performances were achieved for more than 10 and 2 h of continuous operation for p-type and n-type devices, respectively. Accordingly, this work points not only that EGOFETs can be applied to a wider range of applications beyond biosensing but also that these devices can effectively improve their long-term stability by simply treating them with a suitable surfactant.

Rhizoglomus intraradices Improves Plant Growth, Root Morphology and Phytohormone Balance of Robinia pseudoacacia in Arsenic-Contaminated Soils.

Arbuscular mycorrhizal fungi (AMF) are known to improve the resistance of host plants against various heavy metal stresses. However, the arsenic (As) resistance mechanism of AMF-inoculated woody legumes remains unclear. In this study, black locust (Robinia pseudoacacia L.) seedlings were cultivated in potted soils inoculated with or without AMF Rhizoglomus intraradices under three different levels of As stress (0, 100, and 200 mg As kg-1 soil) over 4 months. The objective of this paper was to investigate the effects of AMF on plant growth, root morphology, and the content and ratio of endogenous phytohormones and soil glomalin under As stress condition. As stress toxicity suppressed the AM spore germination and colonization, plant growth, and the content of soil glomalin and changed the morphological characteristics of the roots and the balance of endogenous hormone levels in plants. However, R. intraradices inoculation improved the shoot and root dry weights, total root length, root surface area, root volume, and the number of root forks and tips across all As treatments. R. intraradices inoculation obviously decreased the percentage of root length in the 0- to 0.2-mm diameter class and increased those in the 0.5- to 1.0-mm and >1.0-mm diameter classes; the percentages in the 0.2- to 0.5-mm diameter class were less affected by R. intraradices inoculation. The concentrations of the easily extractable glomalin-related (EE-GRSP) and total glomalin-related soil protein (T-GRSP) were higher in the of R. intraradices-inoculated seedlings than those in the non-inoculated seedlings. Furthermore, R. intraradices inoculation increased the concentrations of indole-3-acetic acid (IAA) and abscisic acid (ABA), but decreased the concentrations of gibberellic acid (GA) and zeatin riboside (ZR). The phytohormone ratios of IAA/ABA, GA/ABA, ZR/ABA, and (IAA + GA + ZR)/IAA in the R. intraradices-inoculated seedlings were lower than those in the non-inoculated seedlings. These results indicated that R. intraradices alleviated As toxicity in R. pseudoacacia seedlings by improving their plant growth, altering root morphology, regulating the concentrations and ratios of phytohormones, and increasing the concentration of soil glomalin. The results suggested that AMF-inoculated R. pseudoacacia seedlings would be a critical factor in successful vegetation restoration and soil development in As-contaminated soils.

Eye-movement evidence for the mental representation of strokes in Chinese characters.

Although strokes are the smallest identifiable units in Chinese words, the fact that they are often embedded within larger units (i.e., radicals and/or characters that comprise Chinese words) raises questions about how and even if strokes are separately represented in lexical memory. The present experiment examined these questions using a gaze-contingent boundary paradigm (Rayner, 1975) to manipulate the parafoveal preview of the first of two-character target words. Relative to a normal preview, the removal of whole strokes was more disruptive (i.e., resulting in longer looking times on targets) than the removal of an equivalent amount of visual information (i.e., number of pixels) from strokes located either in similar locations or throughout the entire character. These findings suggest that strokes are represented as discrete functional units rather than visual features or integral parts of the radicals/characters in which they are embedded. We discuss the theoretical implications of this conclusion for models of Chinese word identification. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Character-complexity effects in Chinese reading and visual search: A comparison and theoretical implications.

Three eye-movement experiments were conducted to examine how the complexity of characters in Chinese words (i.e., number of strokes per character) influences their processing and eye-movement behaviour. In Experiment 1, English speakers with no significant knowledge of Chinese searched for specific low-, medium-, and high-complexity target characters in a multi-page narrative containing characters of varying complexity (3-16 strokes). Fixation durations and skipping rates were influenced by the visual complexity of both the target characters and the characters being searched even though participants had no knowledge of Chinese. In Experiment 2, native Chinese speakers performed the same character-search task, and a similar pattern of results was observed. Finally, in Experiment 3, a second sample of native Chinese speakers read the same text used in Experiments 1 and 2, with text characters again exhibiting complexity effects. These results collectively suggest that character-complexity effects on eye movements may not be due to lexical processing per se but may instead reflect whatever visual processing is required to know whether or not a character corresponds to an episodically represented target. The theoretical implications of this for our understanding of normal reading are discussed.

High performing solution-coated electrolyte-gated organic field-effect 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.

Electrolyte-Gated Organic Field-Effect Transistor Based on a Solution Sheared Organic Semiconductor Blend.

This communication presents a novel electrolyte gated field-effect transistor based on a blend of dibenzo-tetrathiafulvalene and polystyrene deposited through bar-assisted meniscus shearing. This technique allows the fabrication of high performing electronic devices suitable for (bio)sensing applications and might capture industrial interest due to its scalability. The reported devices can operate in aqueous solution with comparable complexity to real samples.

Graphene quantum-dot-doped polypyrrole counter electrode for high-performance dye-sensitized solar cells.

Herein graphene quantum dot (GQD), a graphene material with lateral dimension less than 100 nm, is explored to dope PPy on F-doped tin oxide glass as an efficient counter electrode for high-performance dye-sensitized solar cells (DSSCs). The GQDs-doped PPy film has a porous structure in comparison to the densely structured plain PPy, and displays higher catalytic current density and lower charge transfer resistance than the latter toward I3(-)/I(-) redox reaction. The highest power conversion efficiency (5.27%) for DSSCs is achieved with PPy doped with10% GQDs, which is comparable to that of Pt counter electrode-based DSSCs. This work provides an inexpensive alternative to replace platinum for DSSCs.