Mimicry is the phenomenon in which one species (the mimic) closely resembles another (the model), enhancing its own fitness by deceiving a third party into interacting with it as if it were the ...model. In plants, mimicry is used primarily to gain fitness by withholding rewards from mutualists or deterring herbivores cost-effectively. While extensive work has been documented on putative defence mimicry, limited investigation has been conducted in the field of chemical mimicry. In this study, we used field experiments, chemical analyses, behavioural assays, and electrophysiology, to test the hypothesis that the birthwort Aristolochia delavayi employs chemical mimicry by releasing leaf scent that closely resembles stink bug defensive compounds and repels vertebrate herbivores. We show that A. delavayi leaf scent is chemically and functionally similar to the generalized defensive volatiles of stink bugs and that the scent effectively deters vertebrate herbivores, likely through the activation of TRPA1 channels via (E)-2-alkenal compounds. This study provides an unequivocal example of chemical mimicry in plants, revealing intricate dynamics between plants and vertebrate herbivores. Our study underscores the potency of chemical volatiles in countering vertebrate herbivory, urging further research to uncover their potentially underestimated importance.
As an abundant natural resource, wood has gained great attention for thousands of years, spanning from the primitive construction materials to the modern high‐added‐value engineering materials. The ...unique delicate microstructures and the wonderful properties (e.g., low‐density, high strength and stiffness, good toughness, and environmental sustainability) have made wood a natural source of inspiration that guides researchers to invent various wood‐inspired materials. Herein, as an emerging material system, bioinspired artificial wood, with similar cellular structures and comparable mechanical properties, is discussed in the view of the design concept, fabrication strategy, properties, and possible applications. The present challenges and further research opportunities are also presented for artificial woods to thrive. To achieve the final eco‐friendly artificial wood, more endeavors should be made in biomaterials and biodegradable or recyclable engineering of polymers to gain high mechanical properties and environmental sustainability simultaneously.
Artificial woods have emerged as a novel kind of wood‐inspired engineering material with almost exactly the same channel microstructures and similar wall components. The performances of artificial woods depend on both the oriented channel and wall designs. The rational combination of other engineering polymers and channel‐making techniques hold promise to develop more useful artificial woods.
Energy efficient buildings require materials with a low thermal conductivity and a high fire resistance. Traditional organic insulation materials are limited by their poor fire resistance and ...inorganic insulation materials are either brittle or display a high thermal conductivity. Herein we report a mechanically resilient organic/inorganic composite aerogel with a thermal conductivity significantly lower than expanded polystyrene and excellent fire resistance. Co‐polymerization and nanoscale phase separation of the phenol‐formaldehyde‐resin (PFR) and silica generate a binary network with domain sizes below 20 nm. The PFR/SiO2 aerogel can resist a high‐temperature flame without disintegration and prevents the temperature on the non‐exposed side from increasing above the temperature critical for the collapse of reinforced concrete structures.
Fire not starter: Taking advantage of a co‐polymerization strategy an organic–inorganic binary network hybrid aerogel with a nanoscale homogeneity can be prepared. The phenol‐formaldehyde‐resin/SiO2 aerogel is mechanically resilient and has a thermal conductivity significantly lower than expanded polystyrene and excellent fire resistance.
Mechanized silica nanoparticles, equipped with pillar5arene‐2pseudorotaxane nanovalves, operate in biological media to trap cargos within their nanopores, but release them when the pH is lowered or a ...competitive binding agent is added. Although cargo size plays an important role in cargo loading, cargo charge‐type does not appear to have any significant influence on the amount of cargo loading or its release. These findings open up the possibility of using pillarnarene and its derivatives for the formation of robust and dynamic nanosystems that are capable of performing useful functions.
An outbreak of respiratory illness proved to be infected by a 2019 novel coronavirus, officially named Coronavirus Disease 2019 (COVID-19), was notified first in Wuhan, China, and has spread rapidly ...in China and to other parts of the world. Herein, we reported the first confirmed case of novel coronavirus pneumonia (NCP) imported from China in Taiwan. This case report revealed a natural course of NCP with self-recovery, which may be a good example in comparison with medical treatments.
Abstract
Autism spectrum disorder (ASD) is a common neurodevelopmental disorder. The mechanisms underlying ASD are unclear. Astrocyte alterations are noted in ASD patients and animal models. However, ...whether astrocyte dysfunction is causal or consequential to ASD-like phenotypes in mice is unresolved. Type 2 inositol 1,4,5-trisphosphate 6 receptors (IP3R2)-mediated Ca
2+
release from intracellular Ca
2+
stores results in the activation of astrocytes. Mutations of the IP3R2 gene are associated with ASD. Here, we show that both IP3R2-null mutant mice and astrocyte-specific IP3R2 conditional knockout mice display ASD-like behaviors, such as atypical social interaction and repetitive behavior. Furthermore, we show that astrocyte-derived ATP modulates ASD-like behavior through the P2X2 receptors in the prefrontal cortex and possibly through GABAergic synaptic transmission. These findings identify astrocyte-derived ATP as a potential molecular player in the pathophysiology of ASD.
Solid‐state batteries (SSBs) are regarded as the most promising next‐generation energy storage devices due to their potential to achieve higher safety performance and energy density. However, the ...troubles in the preparation of ultrathin solid‐state electrolytes (SEs) as well as the resultant compromise in mechanical strength greatly limit the safety application of SSBs. Herein, a novel in situ polymerized integrated ultrathin SE/cathode design is developed. The ultrathin ceramic layer supported on the cathode serves not only as a rigid scaffold to prevent direct contact between the cathode and anode but also as active inorganic fillers to enhance the mechanical properties of in situ polymerized SE film. The unique Li‐ion coordination environments as well as the Li hopping mechanism profoundly promote fast ion transport in composite SEs. The in situ polymerized SEs simultaneously achieve the balance in ultrathin thickness (10 µm), fast ion transport (0.65 mS cm−1), superior Young's modulus (66.8 GPa), and excellent interface contact. The pouch cells with practical Li||LiNi0.8Co0.1Mn0.1O2 configuration achieve an ultrahigh volumetric energy density of 1018 Wh L−1 and safety performance. The in situ polymerized integrated ultrathin SE/cathode design exhibits great promise for the practical application of SSBs with high energy density and safety performance.
An in situ polymerized integrated solid‐state electrolyte (SE)/cathode design is developed to achieve 10 µm‐thick SE with fast Li‐ion transport, superior mechanical strength, and excellent interface contact, therefore, enabling the pouch cells an ultrahigh energy density of 1018 Wh L−1.
Reirradiation in standard fractionation for locally advanced recurrent nasopharyngeal carcinoma after a previous course of high-dose radiotherapy is often associated with substantial late toxicity, ...negating its overall benefit. We therefore aimed to investigate the efficacy and safety of hyperfractionation compared with standard fractionation in intensity-modulated radiotherapy.
This multicentre, randomised, open-label, phase 3 trial was done in three centres in Guangzhou, China. Eligible patients were aged 18–65 years with histopathologically confirmed undifferentiated or differentiated, non-keratinising, advanced locally recurrent nasopharyngeal carcinoma. Participants were randomly assigned (1:1) to either receive hyperfractionation (65 Gy in 54 fractions, given twice daily with an interfractional time interval of at least 6 h) or standard fractionation (60 Gy in 27 fractions, given once a day). Intensity-modulated radiotherapy was used in both groups. A computer program generated the assignment sequence and randomisation was stratified by treatment centre, recurrent tumour stage (T2–T3 vs T4), and recurrent nodal stage (N0 vs N1–N2), determined at the time of randomisation. The two primary endpoints were the incidence of severe late complications defined as the incidence of grade 3 or worse late radiation-induced complications occurring 3 months after the completion of radiotherapy until the latest follow-up in the safety population, and overall survival defined as the time interval from randomisation to death due to any cause in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02456506.
Between July 10, 2015, and Dec 23, 2019, 178 patients were screened for eligibility, 144 of whom were enrolled and randomly assigned to hyperfractionation or standard fractionation (n=72 in each group). 35 (24%) participants were women and 109 (76%) were men. After a median follow-up of 45·0 months (IQR 37·3–53·3), there was a significantly lower incidence of grade 3 or worse late radiation-induced toxicity in the hyperfractionation group (23 34% of 68 patients) versus the standard fractionation group (39 57% of 68 patients; between-group difference –23% 95% CI –39 to –7; p=0·023). Patients in the hyperfractionation group had better 3-year overall survival than those in the standard fractionation group (74·6% 95% CI 64·4 to 84·8 vs 55·0% 43·4 to 66·6; hazard ratio for death 0·54 95% CI 0·33 to 0·88; p=0·014). There were fewer grade 5 late complications in the hyperfractionation group (five 7% nasal haemorrhage) than in the standard fractionation group (16 24%, including two 3% nasopharyngeal necrosis, 11 16% nasal haemorrhage, and three 4% temporal lobe necrosis).
Hyperfractionated intensity-modulated radiotherapy could significantly decrease the rate of severe late complications and improve overall survival among patients with locally advanced recurrent nasopharyngeal carcinoma. Our findings suggest that hyperfractionated intensity-modulated radiotherapy could be used as the standard of care for these patients.
Key-Area Research and Development of Guangdong Province, the National Natural Science Foundation of China, the Special Support Program for High-level Talents in Sun Yat-sen University Cancer Center, the Guangzhou Science and Technology Plan Project, and the National Ten Thousand Talents Program Science and Technology Innovation Leading Talents, Sun Yat-Sen University Clinical Research 5010 Program.
For device miniaturization, nanotechnology follows either the “top-down” approach scaling down existing larger-scale devices or the “bottom-up’ approach assembling the smallest possible building ...blocks to functional nanoscale entities. For synthetic nanodevices, self-assembly on surfaces is a superb method to achieve useful functions and enable their interactions with the surrounding world. Consequently, adaptability and responsiveness to external stimuli are other prerequisites for their successful operation. Mechanically interlocked molecules such as rotaxanes and catenanes, and their precursors, that is, molecular switches and supramolecular switches including pseudorotaxanes, are molecular machines or prototypes of machines capable of mechanical motion induced by chemical signals, biological inputs, light or redox processes as the external stimuli. Switching of these functional host–guest systems on surfaces becomes a fundamental requirement for artificial molecular machines to work, mimicking the molecular machines in nature, such as proteins and their assemblies operating at dynamic interfaces such as the surfaces of cell membranes. Current research endeavors in material science and technology are focused on developing either a new class of materials or materials with novel/multiple functionalities by shifting host–guest chemistry from solution phase to surfaces. In this Account, we present our most recent attempts of building monolayers of rotaxanes/pseudorotaxanes on surfaces, providing stimuli-induced macroscopic effects and further understanding on the switchable host–guest systems at interfaces. Biocompatible versions of molecular machines based on synthetic macrocycles, such as cucurbiturils, pillararenes, calixarenes, and cyclodextrins, have been employed to form self-assembled monolayers of gates on the surfaces of mesoporous silica nanoparticles to regulate the controlled release of cargo/drug molecules under a range of external stimuli, such as light, pH variations, competitive binding, and enzyme. Rotaxanes have also been assembled onto the surfaces of gold nanodisks and microcantilevers to realize active molecular plasmonics and synthetic molecular actuators for device fabrication and function. Pillararenes have been successfully used to control and aid the synthesis of gold nanoparticles, semiconducting quantum dots, and magnetic nanoparticles. The resulting organic–inorganic hydrid nanomaterials have been successfully used for controlled self-assembly, herbicide sensing and detection, pesticide removal, and so forth, taking advantage of the selective binding of pillarenes toward target molecules. Cyclodextrins have also been successfully functionalized onto the surface of gold nanoparticles to serve as recycling extractors for C60. Many interesting prototypes of nanodevices based on synthetic macrocycles and their host–guest chemistry have been constructed and served for different potential applications. This Account will be a summary of the efforts made mainly by us, and others, on the host–guest chemistry of synthetic macrocyclic compounds on the surfaces of different solid supports.
All‐solid‐state lithium (Li) metal batteries (ASSLMBs) employing sulfide solid electrolytes have attracted increasing attention owing to superior safety and high energy density. However, the ...instability of sulfide electrolytes against Li metal induces the formation of two types of incompetent interphases, solid electrolyte interphase (SEI) and mixed conducting interphase (MCI), which significantly blocks rapid Li‐ion transport and induces uneven Li deposition and continuous interface degradation. In this contribution, a dynamically stable mixed conducting interphase (S‐MCI) is proposed by in situ stress self‐limiting reaction to achieve the compatibility of Li metal with composite sulfide electrolytes (Li6PS5Cl (LPSCl) and Li10GeP2S12 (LGPS)). The rational design of composite electrolytes utilizes the expansion stress induced by the electrolyte decomposition to in turn constrain the further decomposition of LGPS. Consequently, the S‐MCI inherits the high dynamical stability of LPSCl‐derived SEI and the lithiophilic affinity of Li–Ge alloy in LGPS‐derived MCI. The Li||Li symmetric cells with the protection of S‐MCI can operate stably for 1500 h at 0.5 mA cm−2 and 0.5 mAh cm−2. The Li||NCM622 full cells present stable cycling for 100 cycles at 0.1 C with a high‐capacity retention of 93.7%. This work sheds fresh insight into constructing electrochemically stable interphase for high‐performance ASSLMBs.
A dynamically stable mixed conducting interphase (S‐MCI) is proposed by a stress self‐limiting mechanism to achieve the compatibility of Li metal with composite sulfide electrolytes. The S‐MCI can efficiently reduce Li nucleation overpotential, uniformize Li‐ion flux and promote Li kinetics, leading to the suppression of Li dendrite penetration in all‐solid‐state lithium metal batteries.
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