As one of the main forms and intermediate carriers of energy, it is impressive to expand the application scope of heat energy, thereby boosting innovations in heat harvesting, conversion, storage, ...regulation, and utilization associated with the relevant techniques. Phase change materials (PCMs), as a state‐of‐the‐art latent heat storage technique, have garnered increasing interest in heat‐related applications over the past decades, and abundant high‐performance PCMs with excellent shape stability and salient thermal conductivity have been developed. This review focuses on the issues concerning organic PCMs from the perspectives of flexible, multifunctional, and smart phase change composites, along with emerging applications and processing technologies, which are expected to offer possible guidance for the exploration of next‐generation advanced functional phase change composites.
Next‐generation advanced functional phase change composites are analyzed from the perspectives of myriad phase change materials, promising applications, and mass‐manufactured processing technologies to boost their rapid implementation.
The emerging cryoprotectant replacement method endows hydrogels with nondrying and antifreezing properties, but the low conductivity still limits wider electronic applications. In this work, the ...Hofmeister effect and electrostatic interaction are introduced to improve the conductivity of organohydrogels and their enhancement mechanism are studied in depth. The Hofmeister effect mainly influences the physical properties, such as the pore structure and mechanical strength, which subsequently impacts ion transfer during the solvent replacement process. The lithium and sodium bonds formed by the electrostatic interaction play a more important role in the conductivity of organohydrogels and an overall picture is presented based on the synergistic enhancement of the Hofmeister effect and electrostatic interaction to achieve highly ionic conductive organohydrogels. The champion organohydrogels are applied as soft ionic conductors and antireflective layers in triboelectric, photovoltaic, and thermoelectric applications. The proposed mechanism advances the understanding of the contribution of ions to organohydrogels for wearable electronics.
To reduce the decrease of the conductivity of organohydrogels caused by solvent replacement, the enhancement mechanism of the Hofmeister effect and electrostatic interaction is investigated. Formation of stable lithium and sodium bonds by the electrostatic interaction plays important roles in keeping the conductivity of organohydrogels. The organohydrogels can be used in triboelectric, photovoltaic, and thermoelectric applications.
Ferric uptake regulator (Fur) is a global regulator that controls bacterial iron homeostasis. In this study, a fur deletion mutant of the deep-sea bacterium Shewanella piezotolerans WP3 was ...constructed. Physiological studies revealed that the growth rate of this mutant under aerobic conditions was only slightly lower than that of wild type (WT), but severe growth defects were observed under anaerobic conditions when different electron acceptors (EAs) were provided. Comparative transcriptomic analysis demonstrated that Fur is involved not only in classical iron homeostasis but also in anaerobic respiration. Fur exerted pleiotropic effects on the regulation of anaerobic respiration by controlling anaerobic electron transport, the heme biosynthesis system, and the cytochrome c maturation system. Biochemical assays demonstrated that levels of c-type cytochromes were lower in the fur mutant, consistent with the transcriptional profiling. Transcriptomic analysis and electrophoretic mobility shift assays revealed a primary regulation network for Fur in WP3. These results suggest that Fur may act as a sensor for anoxic conditions to trigger and influence the anaerobic respiratory system.
Lilium is a large genus that includes approximately 110 species distributed throughout cold and temperate regions of the Northern Hemisphere. The species-level phylogeny of Lilium remains unclear; ...previous studies have found universal markers but insufficient phylogenetic signals. In this study, we present the use of complete chloroplast genomes to explore the phylogeny of this genus. We sequenced nine Lilium chloroplast genomes and retrieved seven published chloroplast genomes for comparative and phylogenetic analyses. The genomes ranged from 151,655 bp to 153,235 bp in length and had a typical quadripartite structure with a conserved genome arrangement and moderate divergence. A comparison of sixteen Lilium chloroplast genomes revealed ten mutation hotspots. Single nucleotide polymorphisms (SNPs) for any two Lilium chloroplast genomes ranged from 8 to 1,178 and provided robust data for phylogeny. Except for some of the shortest internodes, phylogenetic relationships of the Lilium species inferred from the chloroplast genome obtained high support, indicating that chloroplast genome data will be useful to help resolve the deeper branches of phylogeny.
Summary
The transportation sector consumes a large amount of fossil fuels consequently exacerbating the global environmental and energy crisis. Fuel‐cell hybrid electric vehicles (FCHEVs) are ...promising alternatives in the continuous transition to clean energy. This article summarizes the recent advances pertaining to the optimization and cutting‐edge design of fuel‐cell hybrid electric vehicles, especially the fuel cell + battery hybrid topology, and discusses current technological bottlenecks hindering the commercialization of FCHEVs. The development of HEVs, markets, environmental and economic benefits, components, topologies, energy management strategies, degradation mechanisms, and safety standards of FCHEVs are reviewed. Proton exchange membrane fuel cells constitute the mainstream and most mature fuel cell technology for automobile applications. Battery hybridization is currently favored among the available FCHEV topological designs to improve the dynamic response and recover the braking energy. Energy management strategies encompassing logic rule‐based simple methods, intelligent control methods, global optimization strategies, and local optimization strategies are described, and issues and challenges encountering FCHEVs are discussed. In addition to promoting the construction of hydrogen supply facilities, future efforts are expected to focus on solving problems such as the high cost, durability of fuel cells, cold start, lifetime of batteries, security and comfort, system optimization, energy management systems, integration, and diagnosis of faults. This review serves as a reference and guide for future technological development and commercialization of FCHEVs.
Highlights
Advances of the optimization and cutting‐edge design of FCHEVs are reviewed.
Battery hybridization is currently favored among the available topological designs.
Benefits, components, topologies, and energy management strategies are described.
Markets, degradation mechanisms, and safety standards of FCHEVs are introduced.
Technological bottlenecks hindering the commercialization of FCHEVs are discussed.
This article summarizes the recent advances pertaining to the optimization and cutting‐edge design of fuel‐cell hybrid electric vehicles, especially the fuel cell + battery hybrid topology, and discusses current technological bottlenecks hindering the commercialization of FCHEVs. Energy management strategies encompassing logic rule‐based simple methods, intelligent control methods, global optimization strategies, and local optimization strategies are described, and issues and challenges encountering FCHEVs are discussed. This review serves as a reference and guide for future technological development and commercialization of FCHEVs.
Freestanding synaptic transistors are fabricated on solution‐processed chitosan membranes. A short‐term memory to long‐term memory transition is observed due to proton‐related electrochemical doping ...under repeated pulse stimulus. Moreover, freestanding artificial synaptic devices with multiple presynaptic inputs are investigated, and spiking logic operation and logic modulation are realized.
Long non-coding RNAs in ischemic stroke Bao, Mei-Hua; Szeto, Vivian; Yang, Burton B ...
Cell death & disease,
02/2018, Letnik:
9, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Stroke is one of the leading causes of mortality and disability worldwide. Uncovering the cellular and molecular pathophysiological processes in stroke have been a top priority. Long non-coding (lnc) ...RNAs play critical roles in different kinds of diseases. In recent years, a bulk of aberrantly expressed lncRNAs have been screened out in ischemic stroke patients or ischemia insulted animals using new technologies such as RNA-seq, deep sequencing, and microarrays. Nine specific lncRNAs, antisense non-coding RNA in the INK4 locus (ANRIL), metastasis-associate lung adenocarcinoma transcript 1 (MALAT1), N1LR, maternally expressed gene 3 (MEG3), H19, CaMK2D-associated transcript 1 (C2dat1), Fos downstream transcript (FosDT), small nucleolar RNA host gene 14 (SNHG14), and taurine-upregulated gene 1 (TUG1), were found increased in cerebral ischemic animals and/or oxygen-glucose deprived (OGD) cells. These lncRNAs were suggested to promote cell apoptosis, angiogenesis, inflammation, and cell death. Our Gene Ontology (GO) enrichment analysis predicted that MEG3, H19, and MALAT1 might also be related to functions such as neurogenesis, angiogenesis, and inflammation through mechanisms of gene regulation (DNA transcription, RNA folding, methylation, and gene imprinting). This knowledge may provide a better understanding of the functions and mechanisms of lncRNAs in ischemic stroke. Further elucidating the functions and mechanisms of these lncRNAs in biological systems under normal and pathological conditions may lead to opportunities for identifying biomarkers and novel therapeutic targets of ischemic stroke.
3D Nanoprinting of Perovskites Chen, Mojun; Yang, Jihyuk; Wang, Zhenyu ...
Advanced materials (Weinheim),
November 1, 2019, Letnik:
31, Številka:
44
Journal Article
Recenzirano
As competing with the established silicon technology, organic–inorganic metal halide perovskites are continually gaining ground in optoelectronics due to their excellent material properties and ...low‐cost production. The ability to have control over their shape, as well as composition and crystallinity, is indispensable for practical materialization. Many sophisticated nanofabrication methods have been devised to shape perovskites; however, they are still limited to in‐plane, low‐aspect‐ratio, and simple forms. This is in stark contrast with the demands of modern optoelectronics with freeform circuitry and high integration density. Here, a nanoprecision 3D printing is developed for organic–inorganic metal halide perovskites. The method is based on guiding evaporation‐induced perovskite crystallization in mid‐air using a femtoliter ink meniscus formed on a nanopipette, resulting in freestanding 3D perovskite nanostructures with a preferred crystal orientation. Stretching the ink meniscus with a pulling process enables on‐demand control of the nanostructure's diameter and hollowness, leading to an unprecedented tubular‐solid transition. With varying the pulling direction, a layer‐by‐layer stacking of perovskite nanostructures is successfully demonstrated with programmed shapes and positions, a primary step for additive manufacturing. It is expected that the method has the potential to create freeform perovskite nanostructures for customized optoelectronics.
3D nanoprinting of organic–inorganic metal halide perovskites is realized with guiding crystallization using a femtoliter ink meniscus in mid‐air.
Objectives
Early recognition of coronavirus disease 2019 (COVID-19) severity can guide patient management. However, it is challenging to predict when COVID-19 patients will progress to critical ...illness. This study aimed to develop an artificial intelligence system to predict future deterioration to critical illness in COVID-19 patients.
Methods
An artificial intelligence (AI) system in a time-to-event analysis framework was developed to integrate chest CT and clinical data for risk prediction of future deterioration to critical illness in patients with COVID-19.
Results
A multi-institutional international cohort of 1,051 patients with RT-PCR confirmed COVID-19 and chest CT was included in this study. Of them, 282 patients developed critical illness, which was defined as requiring ICU admission and/or mechanical ventilation and/or reaching death during their hospital stay. The AI system achieved a C-index of 0.80 for predicting individual COVID-19 patients’ to critical illness. The AI system successfully stratified the patients into high-risk and low-risk groups with distinct progression risks (
p
< 0.0001).
Conclusions
Using CT imaging and clinical data, the AI system successfully predicted time to critical illness for individual patients and identified patients with high risk. AI has the potential to accurately triage patients and facilitate personalized treatment.
Key Point
• AI system can predict time to critical illness for patients with COVID-19 by using CT imaging and clinical data.
Sesquiterpene synthases (STPSs) catalyze carbocation‐driven cyclization reactions that can generate structurally diverse hydrocarbons. The deprotonation‐reprotonation process is widely used in STPSs ...to promote structural diversity, largely attributable to the distinct regio/stereoselective reprotonations. However, the molecular basis for reprotonation regioselectivity remains largely understudied. Herein, we analyzed two highly paralogous STPSs, Artabotrys hexapetalus (−)‐cyperene synthase (AhCS) and ishwarane synthase (AhIS), which catalyze reactions that are distinct from the regioselective protonation of germacrene A (GA), resulting in distinct skeletons of 5/5/6 tricyclic (−)‐cyperene and 6/6/5/3 tetracyclic ishwarane, respectively. Isotopic labeling experiments demonstrated that these protonations occur at C3 and C6 of GA in AhCS and AhIS, respectively. The cryo‐electron microscopy‐derived AhCS complex structure provided the structural basis for identifying different key active site residues that may govern their functional disparity. The structure‐guided mutagenesis of these residues resulted in successful functional interconversion between AhCS and AhIS, thus targeting the three active site residues L311‐S419‐C458/M311‐V419‐A458 that may act as a C3/C6 reprotonation switch for GA. These findings facilitate the rational design or directed evolution of STPSs with structurally diverse skeletons.
Three critical active site residues L311‐S419‐C458/M311‐V419‐A458 were identified as the switch of the regioselective C3/C6 reprotonation of germacrene A in sesquiterpene synthase catalysis through the characterization and engineering of two highly paralogous sesquiterpene synthases, AhCS and AhIS, using a combination of isotopic labeling experiments, cryo‐electron microscopy, and structure‐guided mutagenesis.
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