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Driven by the extensive implementation of information communication technology, collaborative consumption has become more popular. Historically, people have always thought that the best way to get something is to obtain the ownership of it. However, collaborative consumption has recently seen a meteoric rise in popularity due to that obtaining the right to use rather than own. More research into this emerging phenomenon is necessary, notwithstanding the huge impact that collaborative consumption activities have had on companies and individuals. Existing research indicates a lack of knowledge on the factors that motivate or impede user engagement in collaborative consumption. Building on the cost and benefit framework, this research presents a model that examines the effects of perceived benefits (enjoyment and economic reward), perceived costs (privacy risk and security risk) and perceived platform quality (system quality, service quality and information quality) on the intention to engage in the collaborative economy. Using a structural equation modelling approach, 524 active users with experience in car sharing evaluated the research model.The results show that perceived benefits and platform quality positively influence CC participation, the perceived cost reveals a partial support relationship to participate in CC, where security risks are supported but privacy risks are not. This research results will contribute to the research and practice on sharing economy.

Hydrogen sulfide (H2S) could act as a versatile signaling molecule in delaying fruit ripening and senescence. Ethylene (C2H4) also plays a key role in climacteric fruit ripening, but little attention has been given to its interaction with H2S in modulating fruit ripening and senescence. To study the role of H2S treatment on the fruit quality and nutrient metabolism, tomato fruits at white mature stage were treated with ethylene and ethylene plus H2S. By comparing to C2H4 treatment, we found that additional H2S significantly delayed the color change of tomato fruit, and maintained higher chlorophyll and lower flavonoids during storage. Moreover, H2S could inhibit the activity of protease, maintained higher levels of nutritional-related metabolites, such as anthocyanin, starch, soluble protein, ascorbic acid by comparing to C2H4 treatment. Gene expression analysis showed that additional H2S attenuated the expression of beta-amylase encoding gene BAM3 , UDP-glycosyltransferase encoding genes, ethylene-responsive transcription factor ERF003 and DOF22 . Furthermore, principal component analysis suggested that starch, titratable acids, and ascorbic acid were important factors for affecting the tomato storage quality, and the correlation analysis further showed that H2S affected pigments metabolism and the transformation of macromolecular to small molecular metabolites. These results showed that additional H2S could maintain the better appearance and nutritional quality than C2H4 treatment alone, and prolong the storage period of post-harvest tomato fruits.

Plant invasions can alter the behaviour and performance of native herbivorous insects because the insects are evolutionarily naïve to the novel plants. An ecological trap results when native insects prefer invasive plants over their native hosts but suffer reduced fitness on the invaders. Although such traps are predicted to occur frequently, given the prevalence of invasive plants, empirical support for ecological traps and their underlying mechanisms remains sparse. We examined the potential for the invasive plant Spartina alterniflora to act as an ecological trap for the native moth Laelia coenosa, which previously fed mainly on the indigenous plant Phragmites australis in a Chinese saltmarsh. We surveyed Laelia egg densities on Spartina and Phragmites in the field, and determined adult oviposition preference and offspring development on the two plant species. To investigate the causes of adult preference and offspring performance patterns, we compared resource abundance in the field, plant‐odour attractiveness and leaf nutritional and defensive traits between Spartina and Phragmites. We found that Laelia egg density and female preference for ovipositing were higher on Spartina than Phragmites. However, performance of offspring was poorer on Spartina than Phragmites. Spartina dominated a larger area and had greater leaf biomass than Phragmites in the field, and volatile odours released by Spartina were more attractive to Laelia females than those released by Phragmites. Although leaf C, C:P ratio and terpenoid content did not differ significantly between the two plant species, Spartina leaves were tougher and more waxy, had lower N and had higher concentrations of alkaloids and phenolics than Phragmites leaves. Synthesis. Our data suggest that invasive Spartina can create an ecological trap for the native insect Laelia. This trap appears to result from environmental cues (resource availability and leaf odours) that attract the herbivore to the plant, but do not reliably predict the dietary qualities (nutrition and defences) that negatively affect herbivore offspring performance. These findings reveal an important negative effect of plant invasions on resident herbivores and highlight the roles of resource availability and plant traits at different life stages of the insect. Our results suggest that the decoupling of environmental cues and plant qualities of invasive plants can create an ecological trap for native insects, highlighting the roles of resource availability and plant traits at different life stages of insects.

The construction of hierarchically nanoporous composite for high-performance catalytic application is still challenging. In this work, a series of host-in-host ionic porous materials are crafted by encapsulating ionic organic cages into a hyper-crosslinked, oppositely charged porous poly(ionic liquid) (PoPIL) through an ion pair-directed assembly strategy. Specifically, the cationic cage (C-Cage) as the inner host can spatially accommodate a functional Au cluster, forming a [Au⊂C-Cage + ]⊂PoPIL − supramolecular composite. This dual-host molecular hierarchy enables a charge-selective substrate sorting effect to the Au clusters, which amplifies their catalytic activity by at least one order of magnitude as compared to Au confined only by C-Cage as the mono-host (Au⊂C-Cage + ). Moreover, we demonstrate that such dual-host porous system can advantageously immobilize electrostatically repulsive Au⊂C-Cage + and cationic ferrocene co-catalyst (Fer + ) together into the same microcompartments, and synergistically speed up the enzyme-like tandem reactions by channelling the substrate to the catalytic centers via nanoconfinement. The encapsulation of catalysts within hosts is a strategy to tune their reactivity. Here, the authors encapsulate a gold cluster within a porous cage and study its reactivity.

The ability to grow properly sized and good quality crystals is one of the cornerstones of single-crystal diffraction, is advantageous in many industrial-scale chemical processes 1 – 3 , and is important for obtaining institutional approvals of new drugs for which high-quality crystallographic data are required 4 – 7 . Typically, single crystals suitable for such processes and analyses are grown for hours to days during which any mechanical disturbances—believed to be detrimental to the process—are carefully avoided. In particular, stirring and shear flows are known to cause secondary nucleation, which decreases the final size of the crystals (though shear can also increase their quantity 8 – 14 ). Here we demonstrate that in the presence of polymers (preferably, polyionic liquids), crystals of various types grow in common solvents, at constant temperature, much bigger and much faster when stirred, rather than kept still. This conclusion is based on the study of approximately 20 diverse organic molecules, inorganic salts, metal–organic complexes, and even some proteins. On typical timescales of a few to tens of minutes, these molecules grow into regularly faceted crystals that are always larger (with longest linear dimension about 16 times larger) than those obtained in control experiments of the same duration but without stirring or without polymers. We attribute this enhancement to two synergistic effects. First, under shear, the polymers and their aggregates disentangle, compete for solvent molecules and thus effectively ‘salt out’ (that is, induce precipitation by decreasing solubility of) the crystallizing species. Second, the local shear rate is dependent on particle size, ultimately promoting the growth of larger crystals (but not via surface-energy effects as in classical Ostwald ripening). This closed-system, constant-temperature crystallization driven by shear could be a valuable addition to the repertoire of crystal growth techniques, enabling accelerated growth of crystals required by the materials and pharmaceutical industries. A method of growing crystals that does not require undisturbed solutions involves adding polyelectrolytes to the starter solution and shearing (that is, stirring).

H. pylori (Hp) infection has been indicated in the pathogenesis of gastric diseases including gastric cancer (GC). This study aimed at exploring the relationships between Hp infection and gastric diseases including GC in a large dataset of routine patients undergoing gastroscopy. From November 2007 to December 2017, 70,534 first-time visiting patients aged 18-94 years with gastroscopic biopsies were histologically diagnosed and analyzed. Patients' data were entered twice in an Excel spreadsheet database and analyzed using the SPSS (version 22.0) software package and statistical significance was defined as P<0.05 for all analyses. The first interesting observation was age-related twin-peak prevalence profiles (TPPs) for Hp infection, gastritis, and advanced diseases with different time spans (TS) between the first and second occurring peaks. Hp infection and gastritis had TPPs occurring at earlier ages than TPPs of gastric introepithelial neoplasia (GIN) and GC. More patients were clustered at the second occurring TPPs. The time spans (TS) from the first occurring peak of Hp infection to the first occurring peaks of other gastric diseases varied dramatically with 0-5 years for gastritis; 5-15 years for GINs, and 5-20 years for GC, respectively. The number of males with Hp infection and gastric diseases, excluding non-atrophic gastritis (NAG), was more than that of females (P<0.001). We have first observed age-related twin-peak prevalence profiles for Hp infection, gastritis, GIN, and GC, respectively, among a large population of patients undergoing gastroscopy. The second prevalence peak of GC is at ages of 70-74 years indicating that many GC patients would be missed during screening because the cut-off age for screening is 69 years old in China.

Combining the chemo- and biocatalytic sites within an integrated catalyst to orchestrate complex, multi-step reactions is highly desirable yet remains a significant challenge. Here, we introduce an ionic organic cage platform for such a chemoenzymatic catalyst, achieved by electrostatic complexation of cationic molecular cage-encapsulated Pd clusters (Pd@C-Cage + ) and anionic Candida antarctica lipase B. The spatial compartmentalization provided by the cage scaffold averts undesirable coordination interactions between metal and enzyme, while also facilitating substrate channelling between dual active sites in the one-pot tandem dynamic kinetic resolution of amines, resulting in 2.1-2.7 folds enhancement in product yield within the same reaction time, compared to the physical mixture of individual analogues, and even one order of magnitude higher than the mixture of commercial immobilized lipase Novozym 435 and Pd/C. Additionally, the well-defined pore aperture and charged cage skeleton enables precise microenvironment engineering of confined metal sites, providing stringent site/shape selectivity towards substrates featuring different substituents and sizes. This platform is further demonstrated by integrating other metal clusters (e.g., Ru) and enzymes (e.g., Candida antarctica lipase A, Thermomyces lanuginosus lipase, and Glucose oxidase) for a variety of chemoenzymatic reactions, with 2.1–5.3 folds enhancement compared to the physical mixture of individual analogues. Combining chemo- and biocatalytic sites within an integrated catalyst to perform complex, multi-step reactions is highly desirable but challenging. Here, the authors present an ionic organic cage platform for such a chemoenzymatic catalyst, achieved by electrostatic complexation of cationic molecular cage-encapsulated Pd clusters (Pd@C-Cage + ) and anionic Candida antarctica lipase B.

The creation of metal nanoclusters with dimensions ranging from subnanometre to ~2 nm for heterogeneous catalysis has received substantial attention. However, synthesizing these structures while retaining surface activity and avoiding aggregation is challenging. Here, we report a reverse double-solvents approach that enables encapsulation of highly catalytically active Pd nanoclusters inside the newly formed discrete organic molecular cage, RCC3. By encapsulating within the open cavities of soluble RCC3 cages, the obtained Pd nanocluster cores are produced with precisely controlled size (~0.72 nm) and show high solubility, excellent dispersibility and accessibility in solution, presenting significantly enhanced catalytic activities towards various liquid-phase catalytic reactions. Moreover, owing to the effective confinement of cage cavities, the as-prepared Pd nanoclusters possess excellent stability and durability. The strategy of encapsulation of metal nanoclusters within soluble porous organic cages is promising for developing stable and active catalysts. Small metal nanoclusters often display high catalytic activity, but also low stability due to aggregation. Here, Xu and co-workers show that subnanometre Pd clusters can be contained within porous organic cages. Not only do the particles retain high catalytic activity, they also show excellent solubility and stability.

Undifferentiated pleomorphic sarcoma of the liver (UPSL) is a rare pathological type characterized by an undefined mechanism, low incidence, high metastatic rate, aggressive behavior, and an inferior prognosis; no standardized treatment protocols or guidelines currently exist. This article reports the case of an 83-year-old male with UPSL confirmed through surgical resection and pathological biopsy. Postoperatively, he received eight cycles of pembrolizumab, which resulted in a favorable clinical efficacy. With advances in medical technology, the integration of surgery and immunotherapy is expected to play an essential role in treating this rare disease and monitoring its prognosis.

Soft actuators with integration of ultrasensitivity and capability of simultaneous interaction with multiple stimuli through an entire event ask for a high level of structure complexity, adaptability, and/or multi-responsiveness, which is a great challenge. Here, we develop a porous polycarbene-bearing membrane actuator built up from ionic complexation between a poly(ionic liquid) and trimesic acid (TA). The actuator features two concurrent structure gradients, i.e., an electrostatic complexation (EC) degree and a density distribution of a carbene-NH 3 adduct (CNA) along the membrane cross-section. The membrane actuator performs the highest sensitivity among the state-of-the-art soft proton actuators toward acetic acid at 10 −6  mol L −1 (M) level in aqueous media. Through competing actuation of the two gradients, it is capable of monitoring an entire process of proton-involved chemical reactions that comprise multiple stimuli and operational steps. The present achievement constitutes a significant step toward real-life application of soft actuators in chemical sensing and reaction technology. The design of soft actuators which show high sensitivity and allow for simultaneous interaction with multiple stimuli still remains a challenge. Here the authors demonstrate a highly sensitive proton actuator which allows monitoring of an entire process of chemical reactions that comprise multiple stimuli and operational steps.