Search

Purpose: The effectiveness of rhetorical structure is essential to communicate key messages in research articles (RAs). The interdisciplinary nature of library and information science (LIS) has led to unclear patterns and practice of using rhetorical structures. Understanding how RAs are constructed in LIS to facilitate effective scholarly communication is important. Numerous studies investigated the rhetorical structure of RAs in a range of disciplines, but LIS articles have not been well studied. Design/methodology/approach: In this study, the authors encoded rhetorical structures to 2,216 articles in the Journal of the Association for Information Science and Technology covering a period from 2001 to 2018 with the approaches of co-word analysis and visualization. The results show that the predominant rhetorical structures used by LIS researchers follow the sequence of Introduction-Literature Review-Methodology-Result-Discussion-Conclusion (ILMRDC). Findings: The authors' temporal examination reveals the shifts of evolutionary pattern of rhetorical structure in 2008 and 2014. More importantly, the authors' study demonstrates that rhetorical structures have varied greatly across research areas in LIS community. For example, scholarly communication and scientometrics studies tend to exclude literature review in articles. Originality/value: The present paper offers a first systematic examination of how rhetorical structures are used in a representative sample of a LIS journal, especially from a temporal perspective. [ABSTRACT FROM AUTHOR]

The interfacial Dzyaloshinskii–Moriya interactions (iDMIs), occurring at the interfaces of the heavy metal and thin film, are anticipated to yield topologically nontrivial magnon modes, characterized by the Chern number. Based on the heterostructure consisting of a topologically trivial domain sandwiched between two nontrivial domains containing two distinct heavy metal dot arrays with opposite iDMI parameters, we present a theoretical proposal for the emergence of topological antichiral edge states and one-way bulk states, which possess remarkable immunity to backscattering and robustness against disorders. The features result in the generation of copropagating spin currents traveling at opposite edges, compensated by the counterpropagating spin currents confined within a large bulk area. Leveraging the greater tunability, flexibility, and extended transport areas associated with the one-way states, it becomes possible to design magnonic collimation devices. Our work offers us a way for observing intriguing physical phenomena and constructing low-dissipation magnonic devices. [ABSTRACT FROM AUTHOR]

During the observation, various factors can cause variables to be contaminated by measurement errors. In this paper, we consider the estimation for single-index varying-coefficient models where both the response variable and covariates are measured with multiplicative distortion measurement errors. First, we use the conditional absolute mean calibration to calibrate the distorted variables. Based on the calibrated variables, we obtain the estimators of the parameters and coefficient functions by local linear smoothing and estimating equations. Furthermore, we prove that the obtained estimators have asymptotic normality and the estimator of parametric component is still root-n consistent. Finally, two simulation examples and the analysis of body fat data are given to illustrate that the proposed estimators are unbiased, robust and practical. [ABSTRACT FROM AUTHOR]

An important factor in house prices is its location. However, measurement errors arise frequently in the process of observing variables such as the latitude and longitude of the house. The single-index models with measurement errors are used to study the relationship between house location and house price. We obtain the estimators by a SIMEX method based on the local linear method and the estimating equation. To test the significance of the index coefficient and the linearity of the link function, we establish the generalized likelihood ratio (GLR) tests for the models. We demonstrate that the asymptotic null distributions of the established GLR tests follow χ 2 -distributions which are independent of nuisance parameters or functions. Finally, two simulated examples and a real estate valuation data set are given to illustrate the effect of GLR tests. [ABSTRACT FROM AUTHOR]

Ontology fusion in knowledge bases has become less easy, due to the massive capacity involved in the process of semantic similarity calculation. Many similarity calculation methods have been developed, although they are hardly united. This article contributes a low-cost similarity calculation method for ontology fusion, based on the inspiration of binary metrics, with the aim of reducing the size of similarity calculations both spatially and logically. By introducing the definitions of a heterogeneous ontology, entities of ontologies and rules of ontology fusion on the basis of concept fusion and relationship fusion, we put forward the algorithm of main traverse procedure and calculated to be the least cost in time and space in comparison with traditional methods. We adopted three experiments to testify the usability of our approach from the perspective of actual library resources, small datasets and large datasets. In Experiment 1, the bibliographic data from East China Normal University Library were used to show the feasibility and capability of our proposal and present the process of the algorithm. In both Experiments 2 and 3, our approach had at least 88% confidence in detecting accurate merging mappings and also decreased time cost. The test demonstrated a good fusion result. The problem of lower recalls caused by error analysis results from the conflict between the complex structures in ontologies and the recursive functions, which will be improved in the future. [ABSTRACT FROM AUTHOR]

As a scientific field, scientific mapping offers a set of standardized methods and tools which can be consistently adopted by researchers in different knowledge domains to answer their own research questions. This study examined the scientific articles that applied science mapping tools (SMT) to analyze scientific domains and the citations of these application articles. To understand the roles of these application articles in scholarly communication, we analyzed 496 application articles and their citations from 14 SMT by classifying them into library and information science (LIS) and other fields (non-LIS) in terms of both publication venues and analyzed domains. In our study, we found that science mapping, a topic that is deeply situated in the LIS field, has gained increasing attention from various non-LIS scientific fields over the last few years, especially since 2012. Science mapping application studies practically grew up in LIS domain and spread to other fields. The application articles within and outside of the LIS fields played different roles in advancing the application of science mapping and knowledge discovery. Especially, we have discovered the important role of articles, which studied non-LIS domains but published in LIS journals, in advancing the application of SMTs. [ABSTRACT FROM AUTHOR]

We investigate theoretically the surface states of three-dimensional topological insulator cylinder nanowires analytically and numerically. In contrast to the conventional semiconductor cylinder nanowires, these surface states exhibit unique massless Dirac dispersion and interesting transport properties. We find that the persistent charge current and persistent spin current, i.e., the Aharonov-Bohm oscillation, can be induced by the driven magnetic flux. The amplitude of persistent charge current shows an oscillating behavior with increasing the electron density. [ABSTRACT FROM AUTHOR]

Abstract An efficient water reduction system was developed using thermally activated delayed fluorescence (TADF) dyes as organic photosensitizers and a palladium complex as water reduction catalyst. 2,4,5,6-tetrakis(carbazol-9-yl)-1,3-dicyanobenzene (4CzIPN) that has the best fluorescence efficiency displayed the highest photoinduced productivity (TON up to 2567) and was active for 5 days. Based on time-resolved photoluminescence experiments on the photocatalytic system, reductive quenching of the TADF dye was found as main pathway occurring before intersystem crossing takes place. Highlights • The TADF dyes are firstly used as high efficiency and stable photosensitizers in water splitting. • The system of TADF dyes / Pd catalyst display the turnover numbers (TON) up to 2567 and excellent stability for 5 days. • TRPL experiments find the reductive quenching of the TADF dye as main pathway before intersystem crossing takes place. [ABSTRACT FROM AUTHOR]

Wind-induced swing of overhead transmission lines may cause flashover and line tripping, which will greatly jeopardize the normal operation of power transmission system and give rise to great economy loss. This paper analyzed a swing flashover accident on a practical high-voltage (HV) transmission line and calculated the swing angle of the suspension insulator string using the rigid rod method recommended by the Chinese standard. The aerodynamic coefficients of the iced HV transmission lines were obtained through high frequency force balance wind tunnel tests. An improved rigid rod method was then developed for predicting wind-induced swing response of heavily iced transmission lines in mountainous terrain under severe icy weather conditions. Finally, the improved rigid rod method was also extended to deal with general transmission lines with light ice accretion or regular ice shapes. • An improved rigid rod method is newly developed for predicting wind-induced swing response of iced transmission lines. • A wind-induced swing flashover accident on a practical high-voltage transmission line in a complex terrain is analyzed. • Aerodynamic coefficients of heavily iced conductors are obtained through high frequency force balance wind tunnel tests. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to modify recognized clinically relevant post-operative pancreatic fistula (CR-POPF) risk evaluation models with quantitative ultrasound shear wave elastography (SWE) values and identified clinical parameters to improve the objectivity and reliability of the prediction. Methods: Two prospective, successive cohorts were initially designed for the establishment of CR-POPF risk evaluation model and the internal validation. Patients who scheduled to receive pancreatectomy were enrolled. Virtual touch tissue imaging and quantification (VTIQ)-SWE was used to quantify pancreatic stiffness. CR-POPF was diagnosed according to 2016 International Study Group of Pancreatic Fistula standard. Recognized peri-operative risk factors of CR-POPF were analyzed, and the independent variables selected from multivariate logistic regression were used to build the prediction model. Results: Finally, the CR-POPF risk evaluation model was built in a group of 143 patients (cohort 1). CR-POPF occurred in 52/143 (36%) patients. Constructed from SWE values and other identified clinical parameters, the model achieved an area under the receiver operating characteristic curve of 0.866, with sensitivity, specificity, and likelihood ratio of 71.2%, 80.2%, and 3.597 in predicting CR-POPF. Decision curve of modified model revealed a better clinical benefit compared to the previous clinical prediction models. The models were then examined via internal validation in a separate collection of 72 patients (cohort 2). Conclusions: Risk evaluation model based on SWE and clinical parameters is a potential non-invasive way to pre-operatively, objectively predict CR-POPF after pancreatectomy. Clinical relevance statement: Our modified model based on ultrasound shear wave elastography may provide an easy access in pre-operative and quantitative evaluating the risk of CR-POPF following pancreatectomy and improve the objectivity and reliability of the prediction compared to previous clinical models. Key Points: • Modified prediction model based on ultrasound shear wave elastography (SWE) provides an easy access for clinicians to pre-operatively, objectively evaluate the risk of clinically relevant post-operative pancreatic fistula (CR-POPF) following pancreatectomy. • Prospective study with validation showed that the modified model provides better diagnostic efficacy and clinical benefits compared to previous clinical models in predicting CR-POPF. • Peri-operative management of CR-POPF high-risk patients becomes more possible. [ABSTRACT FROM AUTHOR]

Ice shedding from conductors may cause a significant vertical vibration of a transmission line, which may lead to interphase flashover and thereby endanger power transmission. To design a reasonable electric insulation clearance, it requires an accurate estimation of the largest jump height of a conductor following ice shedding, which might be affected by wind actions. This study investigates the coupling effects of wind action and ice shedding on the jump height of an iced conductor. Wind tunnel tests were carried out to obtain aerodynamic force coefficients of the iced conductor with crescent sections. The dynamic responses of a practical extra-high voltage (EHV) transmission line subject to joint actions of ice-shedding and wind were analyzed by numerical simulation. The influence of wind actions, accreted ice thickness, and ice shedding rate were investigated and discussed on the largest jump height of conductors. An empirical formula for estimating the largest jump height was proposed considering the ice-wind joint effects. The accuracy and applicability of the proposed formula were validated through experimental and simulation data. • Wind tunnel tests are carried out to obtain aerodynamic force coefficients of the iced conductor with crescent sections. • Jump heights of a practical transmission line subject to joint actions of ice-shedding and wind are numerically analyzed. • An empirical formula for estimating the largest jump height is newly proposed considering the ice-wind joint effects. [ABSTRACT FROM AUTHOR]

Cyanobacteria are globally important primary producers that have an exceptionally large iron requirement for photosynthesis. In many aquatic ecosystems, the levels of dissolved iron are so low and some of the chemical species so unreactive that growth of cyanobacteria is impaired. Pathways of iron uptake through cyanobacterial membranes are now being elucidated, but the molecular details are still largely unknown. Here we report that the non-siderophore-producing cyanobacterium Synechocystis sp. PCC 6803 contains three exbB-exbD gene clusters that are obligatorily required for growth and are involved in iron acquisition. The three exbB-exbDs are redundant, but single and double mutants have reduced rates of iron uptake compared with wild-type cells, and the triple mutant appeared to be lethal. Short-term measurements in chemically well-defined medium show that iron uptake by Synechocystis depends on inorganic iron (Fe′) concentration and ExbB-ExbD complexes are essentially required for the Fe′ transport process. Although transport of iron bound to a model siderophore, ferrioxamine B, is also reduced in the exbB-exbD mutants, the rate of uptake at similar total [Fe] is about 800-fold slower than Fe′, suggesting that hydroxamate siderophore iron uptake may be less ecologically relevant than free iron. These results provide the first evidence that ExbB-ExbD is involved in inorganic iron uptake and is an essential part of the iron acquisition pathway in cyanobacteria. The involvement of an ExbB-ExbD system for inorganic iron uptake may allow cyanobacteria to more tightly maintain iron homeostasis, particularly in variable environments where iron concentrations range from limiting to sufficient. [ABSTRACT FROM AUTHOR]

With the development in the miniaturization, intellectualization and dexterity of fuze, the 3D package is the most promising technology to realize fuze miniaturization. Through-silicon via (TSV), the key technology of 3D packages, has the advantages of small package size and low power consumption, and is widely used in microelectronic system integration. A TSV-based 3D package technology for MEMS fuze is presented. The work mode of MEMS fuze requires that the resistance change of TSV in the allowable range at a high transient current when the fuze is detonating. Temperature curve of TSV at a high transient current is calculated using the finite element analysis software. Three groups of TSVs are experimented: 40 V, 330 μF capacitor discharge; 10 V, 330 μF capacitor discharge; and 4 V, 100 μF capacitor discharge. The potential failure modes and transient current carrying capacity of TSV are obtained through the comparison of simulation and experimental results. The result shows that the TSV package can meet the normal working of the MEMS fuze in the conditions of 10 V, 330 μF capacitor discharge and 4 V, 100 μF capacitor discharge. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this study is to construct a Chinese information science resource ontology and to explore a new method for semiautomatic ontology construction. Design/methodology/approach – More than 8,290 articles indexed in the Chinese Social Science Citation Index (CSSCI), covering the years 2001 to 2010, were included in this study. Statistical analysis, co-occurrence analysis, and semantic similarity methods were applied to the selected articles. The ontology was built using existing construction principles and methods, as well as categories and hierarchy definitions based on CSSCI indexing fields. Findings – Seven categories were found to be relevant for the Chinese information science resource ontology, which, in this study, consists of a three-tier architecture, 78,291 instances, and 182,109 pairs of semantic relations. These results indicate the following: further improvements are required in ontology construction methods; resource ontology is a breakthrough concept in ontology studies; the combination of semantic similarities and co-occurrence analysis can quantitatively describe relationships between concepts. Originality/value – This study pioneers the resource ontology concept. It is one of the first to combine informetric methods with semantic similarity to reveal deep relationships in textual data. [ABSTRACT FROM AUTHOR]

Purpose – The paper aims to develop a new method for potential relations retrieval. It aims to find common aspects between co-occurrence analysis and ontology to build a model of semantic information retrieval based on co-occurrence analysis. Design/methodology/approach – This paper used a literature review, co-occurrence analysis, ontology build and other methods to design a model and process of semantic information retrieval based on co-occurrence analysis. Archaeological data from Wuhan University Library's bibliographic retrieval systems was used for experimental analysis. Findings – The literature review found that semantic information retrieval research mainly concentrates on ontology-based query techniques, semantic annotation and semantic relation retrieval. Moreover most recent systems can only achieve obvious relations retrieval. Ontology and co-occurrence analysis have strong similarities in theoretical ideas, data types, expressions, and applications. Research limitations/implications – The experiment data came from a Chinese university which perhaps limits its usefulness elsewhere. Practical implications – This paper constructed a model to understand potential relations retrieval. An experiment proved the feasibility of co-occurrence analysis used in semantic information retrieval. Compared with traditional retrieval, semantic information retrieval based on co-occurrence analysis is more user-friendly. Originality/value – This study is one of the first to combine co-occurrence analysis with semantic information retrieval to find detailed relationships. [ABSTRACT FROM AUTHOR]

Aerodynamic characteristics of iced conductors were investigated by the wind tunnel test. Under the homogeneous turbulence of 5% intensity, aerodynamic force coefficients of single and bundle conductors were obtained at angles of attack between 0°~180°. The variation patterns of aerodynamic forces on the iced conductors with respect to wind angels of attack were systematically studied for the ice thickness of 0.25, 0.5, 0.75 and 1 times of the conductor diameter. The differences of aerodynamic force characteristics for single and bundle conductors were identified and discussed. Based on the Den Hartog and Nigol's mechanisms of galloping, the ranges of attack sensitive to galloping were analyzed. The results show that lift and torsion force coefficients reach peak values at angles of attack between 15°~20°. For bundle conductors, lift force curve is agree with the curve of single conductor approximately. Drag force coefficients were smaller than those of single conductor at some wind angles. There are noticeably differences of torsion coefficients existed between bundle conductors and single conductor. According to two classical galloping mechanisms, wind angles of 15°~30° are critical for the galloping of iced conductors with crescent shapes. [ABSTRACT FROM AUTHOR]

We present a simplified tight-binding (TB) model to describe the low-energy physics of monolayer 1T' transition metal dichalcogenides (TMDCs). The TB model is constructed by combining symmetry analysis and first-principle calculations. Our TB model accurately reproduces the electronic structures near the Fermi energy and provides a better representation of energy band inversion. By considering spin–orbit coupling (SOC), our TB model successfully reproduces the opening of the bandgap, characterizes nontrivial topology, and predicts corresponding helical edge states. Additionally, using this TB model, we observe that quantized electronic conductance remains robust under significant disorder intensity. However, the robustness of the edge states can be suppressed by the Zeeman fields and SOC strength in the scattering zone. Furthermore, moderate concentrations of vacancy disorder destroy the topological protection and eliminate quantized conductance. Our TB model serves as a starting point for a comprehensive understanding of the properties of these materials and can guide future research on superconductivity, strain, and correlation effects. [ABSTRACT FROM AUTHOR]

Abstract: A comparative study was made of Mung bean epoxide hydrolases-catalyzed asymmetric hydrolysis of styrene oxide to (R)-1-phenyl-1,2-ethanediol in an n-hexane/buffer biphasic system containing various hydrophilic ionic liquids (ILs). Compared to the n-hexane/buffer biphasic system alone, addition of a small amount of hydrophilic ILs reduced the amount of non-enzymatic hydrolysis, and improved the reaction rate by up to 22%. The ILs with cation containing an alkanol group, namely [C2OHMIM][BF4] and [C2OHMIM][TfO], and the choline amino acid ILs [Ch][Arg] and [Ch][Pro] were found to be the most suitable co-solvents for the reaction, owing to their good biocompatibility with the enzyme, which led to high initial rates (0.99–1.25μmol/min) and high product e.e.s (95%). When substrate concentration was around 30mM, where optimal performance was observed with the IL-containing systems, the product e.e. was improved from 90% without ILs to ≥95% in the presence of ILs. [Copyright &y& Elsevier]

Cyanobacteria are known to survive in iron-deficient environments, but the ways in which they acquire Fe and acclimate are not completely understood. Here we report a novel gene sll1263 that is required for Synechocystis sp. strain PCC 6803 to grow under iron-deficient conditions. sll1263 encodes a putative cation diffusion facilitator protein (CDF) that shows 50% amino acid similarity with ferrous iron efflux protein (FieF) of heterotrophic bacteria. In bacteria, the gene product is involved in metal export from the cell, but in Synechocystis sll1263 plays a role in iron uptake. The results show that expression of sll1263 was induced by iron-deficient conditions and its inactivation significantly decreased the growth rate of an sll1263– mutant. Other genes known to be required for Fe acquisition were also strongly up-regulated in the mutant even in the presence of high Fe. Overexpression of sll1263 increased growth under iron deficiency but reduced growth under high-iron stress, suggesting that the gene product was involved in iron uptake rather than detoxification. Expression of FieF in the sll1263– mutant was unable to rescue the Fe-deficient phenotype, but Sll1263 completely restored it. Measurements of cellular iron content and the iron uptake rate showed that they were significantly less in the sll1263– mutant than in the wild type, consistent with a role for sll1263 in iron uptake. We hypothesize that the low-iron habitats and high-iron requirements of cyanobacteria may be the reason why cyanobacterial CDF protein functions in Fe uptake and not efflux as in non-photosynthetic bacteria. [ABSTRACT FROM AUTHOR]

Abstract: The asymmetric hydrolysis of styrene oxide to (R)-1-phenyl-1,2-ethanediol using Mung bean epoxide hydrolases was, for the first time, successfully conducted in an ionic liquid (IL)-containing biphasic system. Compared to aqueous monophasic system, IL-based biphasic systems could not only dissolve the substrate, but also effectively inhibit the non-enzymatic hydrolysis, and therefore markedly improve the reaction efficiency. Of all the tested ILs, the best results were observed in the biphasic system containing C4MIM·PF6, which exhibited good biocompatibility with the enzyme and was an excellent solvent for the substrate. In the C4MIM·PF6/buffer biphasic system, it was found that the optimal volume ratio of IL to buffer, reaction temperature, buffer pH and substrate concentration were 1/6, 35°C, 6.5 and 100mM, respectively, under which the initial reaction rate, the yield and the product e.e. were 18.4mM/h, 49.4% and 97.0%. The biocatalytic process was shown to be feasible on a 500-mL preparative scale. [Copyright &y& Elsevier]

Abstract: The biocatalytic enantioselective reduction of 4′-methoxyacetophenone to (S)-1-(4-methoxyphenyl)ethanol was successfully conducted in a hydrophilic IL-containing co-solvent system using immobilized Rhodotorula sp. AS2.2241 cells. Of all the tested ILs, the best results were observed with the novel IL 1-(2′-hydroxy)ethyl-3-methylimidazolium nitrate (C2OHMIM·NO3), which showed a good biocompatibility with the cells and increased the cell membrane permeability moderately, thus improving the efficiency of the bioreduction. To better understand the bioreduction, several crucial influential variables were also examined. The optimal C2OHMIM·NO3 content, buffer pH, reaction temperature and substrate concentration were 5.0% (v/v), 8.5, 25°C and 12mM, respectively. Under the optimized conditions, the initial reaction rate, the maximum yield and the product e.e. were 9.8μmol/hgcell, 98.3% and >99%, respectively, which are much better than the results previously reported. The established biocatalytic system has proven to be highly effective for the reduction of other aryl ketones. Also, the cells exhibited excellent operational stability in the presence of C2OHMIM·NO3. Moreover, the ILs can accumulate within the cells, suggesting that ILs are likely to interact with the related enzymes within the cells. [Copyright &y& Elsevier]

In the present study, such carbohydrate-derived catalysts have been prepared from various carbohydrates such as d-glucose, sucrose, cellulose and starch. The catalytic and textural properties of the prepared catalysts have been investigated in detail and it was found that the starch-derived catalyst had the best catalytic performance. The carbohydrate-derived catalysts exhibited substantially higher catalytic activities for both esterification and transesterification compared to the two typical solid acid catalysts (sulphated zirconia and Niobic acid), and gave markedly enhanced yield of methyl esters in converting waste cooking oils containing 27.8wt% high free fatty acids (FFAs) to biodiesel. In addition, under the optimized reaction conditions, the starch-derived catalyst retained a remarkably high proportion (about 93%) of its original catalytic activity even after 50 cycles of successive re-use and thus displayed very excellent operational stability. Our results clearly indicate that the carbohydrate-derived catalysts, especially the starch-derived catalyst, are highly effective, recyclable, eco-friendly and promising solid acid catalysts that are highly suited to the production of biodiesel from waste oils containing high FFAs. [Copyright &y& Elsevier]

Abstract: In this paper, we show the substrate 4-(trimethylsilyl)-3-butyn-2-one is unstable, and can be easily cleaved into a carbonyl alkyne and trimethylhydroxysilane in aqueous buffer with pH above 6.0. However, this problem could be effectively solved by lowering the buffer pH. Meanwhile, the efficient synthesis of enantiopure (S)-4-(trimethylsilyl)-3-butyn-2-ol, a key intermediate for preparing a 5-lipoxygenase inhibitor, has been successfully conducted through the asymmetric reduction of 4-(trimethylsilyl)-3-butyn-2-one with immobilized Candida parapsilosis CCTCC M203011 cells. For optimization of the reaction, various influential variables, such as buffer pH, co-substrate concentration, reaction temperature and substrate concentration, were systematically examined. All the factors mentioned above had effect on the reaction to some extent. The optimal buffer pH, co-substrate concentration, reaction temperature and substrate concentration were 5.0, 65.3mM, 30°C and 3.0mM, respectively, under which the maximum yield and product e.e. were as high as 81.3% and >99.9% after a reaction time of 1h, which are much higher than the corresponding values previously reported. [Copyright &y& Elsevier]

Abstract: Immobilized Candida antarctica lipase B (Novozym 435)-catalyzed enantioselective hydrolysis of d,l-phenylglycine methyl ester to enatiopure d-phenylglycine was successfully conducted in the systems with ionic liquids (ILs). Novozym 435 exhibited excellent activity and enantioselectivity in the system containing the IL BMIM·BF4 compared to several typical organic solvents tested. It has been found that the cations and, particularly, the anions of ILs have a significant effect on the reaction, and the IL BMIM·BF4, which shows to be the most suitable for the reaction, gave the highest initial rate and enantioselectivity among various ILs examined. The reaction became much less active and enantioselective in the systems with BMIM·HSO4. Also, it was noticed that the enzymatic hydrolysis was strongly dependent on BMIM·BF4 content in the co-solvent systems and the favorable content of the IL was 20% (v/v). Of the assayed four co-solvents and phosphate buffer, the lowest apparent K m and activation energy, and the highest V max of the reaction were achieved using 20% (v/v) BMIM·BF4 co-solvent with phosphate buffer. Additionally, various influential variables were investigated. The optimum pH, substrate concentration, reaction temperature and shaking rate were 8.0, 80mM, 25–30°C and 150rpm, respectively, under which the initial rate, the residual substrate e.e. and the enantioselectivity were 2.46mM/min, 93.8% (at substrate conversion of 53.0%) and 38, respectively. When the hydrolysis was performed under reduced pressure, the initial rate (2.64mM/min) and the enantioselectivity (E =43) were boosted. [Copyright &y& Elsevier]

The initial rate and enantioselectivity of enzymatic asymmetric hydrolysis of amino acid esters were examined in methylimidazolium-based ionic liquids with anions including tetrafluoroborate, chloride, bromide and bisulfate and in typical organic solvents. Papain displayed much higher enantioselectivity but lower activity in phosphate buffer solution of 1-butyl-3-methylimidazolium tetrafluoroborate BMIM·BF 4 than in other media tested (i.e. E =100, V 0 =0.21?mM?min -1 in BMIM·BF 4 , E =2, V 0 =0.43?mM?min -1 in phosphate buffer, E =14–92, V 0 =0.22–0.25?mM?min -1 in organic solvents for D,L-phenylglycine methyl ester). The influence of BMIM·BF 4 on enzyme activity and enantioselectivity also varied with the substrate and the enzyme used. All of the enzymes assayed showed no activity or low enantioselectivity in the ILs with anions including chloride, bromide and bisulfate. [ABSTRACT FROM AUTHOR]

Synthesis of optically active organosilyl alcohol via asymmetric reduction of prochiral acyl silane with immobilized Saccharomyces cerevisiae type II (a mutant from S. cerevisiae by UV irradiation treatment, named UVSC II) cells compared to free UVSC II cells was studied. It has been found that higher yield and enantiomeric excess (e.e.) of the product could be achieved with immobilized UVSC II cells. To further enhance the product yield and the product e.e., an aqueous/organic biphasic system was used as the reaction medium. The influence of various factors, such as shake speed, organic solvent, volume ratio of water phase to organic phase, buffer pH of water phase, reaction temperature and substrate concentration, was systematically studied and the reaction conditions were optimized with respect to the initial reaction rate, the product yield and the product e.e. All the above-mentioned factors had effect on the reaction to some extent. n-Hexane was found to be the best organic solvent. The optimum shake speed, volume ratio of water phase to organic phase, buffer pH, reaction temperature and substrate concentration were 150 rpm, 1/2, 8.0, 30 °C and 42 mM, respectively, under which the product yield and the product e.e. were as high as 97.4 and 95.4%. [Copyright &y& Elsevier]

Recycling the end-of-life lithium-ion batteries including the lithium iron phosphate (LiFePO 4) battery has been one of the most important technology areas since electric vehicles are gradually dominating the way of transportation. For the recycling of LiFePO 4 batteries, the regeneration of pure iron phosphate dihydrate (FePO 4 ∙2H 2 O) from spent cathode material is essential but difficult. The challenge is how to effectively synthesize battery-grade iron phosphate from the impurity-bearing acid solution by precipitation since the spent cathode powder usually holds various impurities. To avoid the introduction of impurities into the iron phosphate, a one-step spontaneous precipitation and phase transformation mode without acidity adjustment was preferred and studied in this work. The focus of this research included the process of phase transformation from amorphous to crystalline, and its effects on precipitation and the properties of the precipitate. It was interestingly found that there was an induction period for phase transformation from amorphous FePO 4 ∙ x H 2 O to monoclinic FePO 4 ∙2H 2 O during the precipitation, which was distinctly shortened with the elevated temperature. Phase transformation led to fast increased precipitation efficiency, morphology evolution, and composition change, which benefited the consistency of iron phosphate. Phase transformation could be kinetically described by the JMA equation, with a rate-limiting step of materials diffusion towards the nucleation point and an activation energy of 20.4 kJ/mol. The critical crystal size for transformation was increasing along with the temperature's raising, which was ascribed to the changes in the volume energy and the surface energy. The results in this study have built the feasibility of chemically regenerating FePO 4 ∙2H 2 O precursors from the spent cathode powder by precipitation purification in an acidic medium. • A one-step spontaneous precipitation and phase transformation process is proposed to regenerate FePO 4 ∙2H 2 O precursor from spent LiFePO 4 cathode powder. • Phase transformation during the precipitation benefits the recovery efficiency of iron phosphate. • Temperature and time are determined experimentally to be the two critical factors affecting the phase transformation. • Phase transformation is kinetically controlled by diffusion, with an activation energy of 20.4 kJ/mol. • There is a critical crystal size for the phase transformation, which becomes larger with raised temperature. [ABSTRACT FROM AUTHOR]

Depuis quelques années, on accorde une attention considérable aux méthodes d'analyse des données longitudinales. L'examen de certaines des questions qui entourent l'application de l'analyse de régression a été entrepris; l'exercice porte sur les aspects de ces questions liés à une étude sur les effets de la pollution de l'air sur la santé, menée auprès d'un groupe d'asthmatiques. Les enregistrements quotidiens du nombre d'heures où les symptômes d'asthme étaient présents se sont révélés être positivement liés à la concentration moyenne quotidienne de soufre réduit total et à l'apport quotidien en anti-inflammatoires non stéroïdiens. Ce constat a été corroboré par l'application de trois modèles statistiques différents. [ABSTRACT FROM AUTHOR]

The innovation performance of Chinese wind power enterprises has not been effectively improved, which may be caused by the behavior of enterprises using the information asymmetry between government and enterprises to camouflage R & D and obtain policies incentives. Therefore, this paper attempts to construct an evolutionary game model of tax incentives in complex network, introduces technology spillover and reputation cost, and discusses the diffusion of R & D in Chinese wind power industry. The results show that: (1) Reducing technology spillover not only contributes to the R & D diffusion, but also reduces the peak in the proportion of enterprises with camouflaging R & D. (2) Increasing reputation cost of violations can accelerate enterprises to reach the equilibrium and reduce the time that the proportion of the behavior with camouflaging R & D decreases. (3) The increase in incentives of lower tax rate for high-tech enterprises will create "lowland effect" for high-tech enterprises. And the increase in incentives of extra deduction for R & D expenses will increase the R & D diffusion of non-high-tech enterprises, while also suppressing the peak of the proportion in non-high-tech enterprises with camouflaging R & D. [ABSTRACT FROM AUTHOR]

OBJECTIVES: To evaluate the efficacy of the radiomics model based on preoperative B-mode ultrasound (BMUS) and shear wave elastography (SWE) for predicting the occurrence of clinically relevant-postoperative pancreatic fistula (CR-POPF). METHODS: Patients who were scheduled to undergo pancreatectomy were prospectively enrolled and received ultrasound assessment within one week before surgery. The risk factors of POPF (grades B and grades C) were analyzed. Preoperative BMUS images, SWE values of pancreatic lesions and surrounding parenchyma were used to build preoperative prediction radiomics models. Radiomic signatures were extracted and constructed using a minimal Redundancy Maximal Relevance (mRMR) algorithm and an L1 penalized logistic regression. A combined model was built using multivariate regression which incorporated radiomics signatures and clinical data. RESULTS: From January 2020 to November 2021, a total of 147 patients (85 distal pancreatectomies and 62 pancreaticoduodenectomies) were enrolled. During the three-week follow-up after pancreatectomy, the incidence rates of grade B/C POPF were 28.6% (42/147). Radiomic signatures constructed from BMUS of pancreas parenchymal regions (panRS) achieved an area under the receiver operating characteristic curve (AUC) of 0.75, accuracy of 68.7%, sensitivity of 85.7 %, and specificity of 61.9 % in preoperative noninvasive prediction of CR-POPF. The AUC of the radiomics model increased to 0.81 when panRS was used for the prediction of CR-POPF after pancreaticoduodenectomy. CONCLUSIONS: Radiomics model based on ultrasound images was potentially useful for predicting CR-POPF. Patients with high-risk factors should be closely monitored when postoperation. [ABSTRACT FROM AUTHOR]

Amygdalus communis L. is rich in high-quality protein and its natural peptides have potential in controlling and preventing diseases. The objective of this study was to evaluate the hypoglycemic activity of bioactive peptides obtained from Amygdalus communis L. protein by synergistic hydrolysis of trypsin and protamex. After ultrafiltration and purification, active peptide B4 with small molecular weight in four hypoglycemic active peptides showed the best inhibitory activities on α -amylase and α -glucosidase. Moreover, insulin resistance model was established with HepG2 cells to study the hypoglycemic mechanism of active peptide B4. The experimental results confirmed that the active peptide B4 was able to up-regulate GYS1 gene mRNA expression and down-regulate PEPCK, G6Pase and GP gene mRNA expression. Meanwhile, active peptide B4 significantly increased the glucose consumption and glycogen synthesis in IR-HepG2. This research enhances the additional value of nut proteins and contributes to the development of potential functional products to expand their application in the food field. [Display omitted] • Amygdalus communis L. peptide was obtained by multienzyme hydrolysis strategy. • The best hypoglycemic effect of active peptide B4 was separated from enzymatic hydrolysate. • Active peptide B4 showed potential bioactivity as antidiabetic agents. [ABSTRACT FROM AUTHOR]

Finding relevant publications is a common task. Typically, a researcher browses through a list of publications and traces additional relevant publications. When relevant publications are identified, the list may be expanded by the citation links of the relevant publications. The information needs of researchers may change as they go through such iterative processes. The exploration process quickly becomes cumbersome as the list expands. Most existing academic search systems tend to be limited in terms of the extent to which searchers can adapt their search as they proceed. In this article, we introduce an adaptive visual exploration system named PaperPoles to support exploration of scientific publications in a context‐aware environment. Searchers can express their information needs by intuitively formulating positive and negative queries. The search results are grouped and displayed in a cluster view, which shows aspects and relevance patterns of the results to support navigation and exploration. We conducted an experiment to compare PaperPoles with a list‐based interface in performing two academic search tasks with different complexity. The results show that PaperPoles can improve the accuracy of searching for the simple and complex tasks. It can also reduce the completion time of searching and improve exploration effectiveness in the complex task. PaperPoles demonstrates a potentially effective workflow for adaptive visual search of complex information. [ABSTRACT FROM AUTHOR]

We report for the first time the usage of Millettia speciosa Champ cellulose (MSCC) and carboxymethylcellulose (MSCCMC) for the fabrication of 3D-network hydrogel as delivery system for probiotics. The structural features, swelling behavior and pH-responsiveness of MSCC-MSCCMC hydrogels and their encapsulation and controlled-release behavior for Lactobacillus paracasei BY2 (L. paracasei BY2) were mainly studied. Structural analyses demonstrated that MSCC-MSCCMC hydrogels with porous and network structures were successfully synthesized through the crosslinking of –OH groups between MSCC and MSCCMC molecules. An increasing concentration of MSCCMC significantly improved the pH-responsiveness and swelling ability of the MSCC-MSCCMC hydrogel toward neutral solvent. Besides, the encapsulation efficiency (50.38–88.91 %) and release (42.88–92.86 %) of L. paracasei BY2 were positively correlated with the concentration of MSCCMC. The higher the encapsulation efficiency was, the higher the release in the target intestine. However, due to the existence of bile salts, controlled-release behavior decreased the survivor rate and physiological state (degrading cholesterol) of encapsulating L. paracasei BY2. Even so, the number of viable cells encapsulated by hydrogels still reached the minimum effective concentration in the target intestine. This study provides an available reference for the practical application of hydrogels fabricated from the cellulose of the Millettia speciosa Champ plant for probiotic delivery. [ABSTRACT FROM AUTHOR]

Background: Xylo-oligomers are a kind of high value-added products in biomass fractionation. Although there are several chemical methods to obtain xylo-oligomers from biomass, the reports about the deep eutectic solvents (DESs)-mediated co-production of xylo-oligomers and fermentable sugars and the related kinetic mechanism are limited. Results: In this work, glycolic acid-based DESs were used to obtain xylo-oligomers from corncob. The highest xylo-oligomers yield of 65.9% was achieved at 120 °C for 20 min, of which the functional xylo-oligosaccharides (XOSs, DP 2–5) accounted for up to 31.8%. Meanwhile, the enzymatic digestion of cellulose and xylan in residues reached 81.0% and 95.5%, respectively. Moreover, the addition of metal inorganic salts significantly accelerated the hydrolysis of xylan and even the degradation of xylo-oligomers in DES, thus resulting in higher selectivity of xylan removal. AlCl3 showed the strongest synergistic effect with DES on accelerating the processes, while FeCl2 is best one for xylo-oligomers accumulation, affording the highest xylo-oligomers yield of 66.1% for only 10 min. Furthermore, the kinetic study indicates that the 'potential hydrolysis degree' model could well describe the xylan hydrolysis processes and glycolic acid/lactic acid (3:1) is a promising solvent for xylo-oligomers production, in particular, it worked well with FeCl2 for the excellent accumulation of xylo-oligomers. Conclusions: Glycolic acid-based deep eutectic solvents can be successfully applied in corncob fractionation with excellent xylo-oligomers and fermentable sugars yields on mild conditions, and the large amount of xylo-oligosaccharides accumulation could be achieved by specific process controlling. The strategies established here can be useful for developing high-valued products from biomass. [ABSTRACT FROM AUTHOR]

In the study, monodispersed silver nanoparticles (AgNPs) with an average diameter of 9.57 nm were efficiently and controllably biosynthesized by a reductase from Fusarium solani DO7 only in the presence of β-NADPH and polyvinyl pyrrolidone (PVP). The reductase responsible for AgNP formation in F. solani DO7 was further confirmed as 1,4-α-glucosidase. Meanwhile, based on the debate on the antibacterial mechanism of AgNPs, this study elucidated in further depth that antibacterial action of AgNPs was achieved by absorbing to the cell membrane and destabilizing the membrane, leading to cell death. Moreover, AgNPs could accelerate the catalytic reaction of 4−nitroaniline, and 86.9% of 4-nitroaniline was converted to p-phenylene diamine in only 20 min by AgNPs of controllable size and morphology. Our study highlights a simple, green, and cost-effective process for biosynthesizing AgNPs with uniform sizes and excellent antibacterial activity and catalytic reduction of 4-nitroaniline. [ABSTRACT FROM AUTHOR]

An acid polysaccharide, named HP, was produced by endophytic Penicillium javanicum MSC-R1 isolated from southern medicine Millettia speciosa Champ. The molecular weight of HP was 37.8 kDa and consisted of Ara f , Gal р , Glc р , Man р , and Glc р A with a molar ratio of 1.09: 3.47: 68.48: 16.59: 8.85. The glycosidic linkage of HP was proven to be →3, 4)-α– D -Glc р -(1→6)-α- D -Man р -(1→, →3, 4)-α- D -Glc р -(1→4)-α- D -Glc р -(1→, →3), →6)-α- D -Man р -(1→4)-α- D -Glc р -(1→, →3), β- D -Gal р -(1→3)-α- D -Glc р -(1→, →4), →5)-α- L -Ara f –(1→3)-α- D -Glc р -(1→, →4), →6)-α- D -Man р -(1→4)-α- D -GlcA р -(1→ and →4)-α- D -GlcA р -(1→4)-α-D-Glc р -(1→, →3). Additionally, 250 μg/mL of HP possessed nontoxicity to RAW 264.7 cells and exhibited anti-inflammation activity. HP could significantly restrain the amount of tumor necrosis factor-α, interleukin-6 and NO release in RAW264.7, which property is possibly associated with its abundant glucosidic linkage. These results indicated that HP could be regarded as a ponderable ingredient for the health-beneficial functional foods. [Display omitted] • Endophytic fungi were selected by EPS yield and antioxidant activity of polysaccharide from M.speciosa. • Molecular weight and monosaccharide composition of HP were similar to polysaccharide extracted from the roots of M.speciosa. • HP exhibited a triple helical conformation with abundant glucosidic linkage. • HP showed significantly anti-inflammatory activity associated with structural characteristics. [ABSTRACT FROM AUTHOR]

Objective: To investigate whether the dynamic contrast-enhanced ultrasound (DCE-US) analysis and quantitative parameters could be helpful for predicting histopathologic grades of pancreatic neuroendocrine tumors (pNETs). Methods: This retrospective study conducted a comprehensive review of the CEUS database between March 2017 and November 2021 in Zhongshan Hospital, Fudan University. Ultrasound examinations were performed by an ACUSON Sequioa unit equipped with a 3.5 MHz 6C−1 convex array transducer, and an ACUSON OXANA2 unit equipped with a 3.5 MHz 5C−1 convex array transducer. SonoVue® (Bracco Inc., Milan, Italy) was used for all CEUS examinations. Time intensity curves (TICs) and quantitative parameters of DCE-US were created by Vuebox® software (Bracco, Italy). Inclusion criteria were: patients with histopathologically proved pNETs, patients who underwent pancreatic B-mode ultrasounds (BMUS) and CEUS scans one week before surgery or biopsy and had DCE-US imaging documented for more than 2 min, patients with solid or predominantly solid lesions and patients with definite diagnosis of histopathological grades of pNETs. Based on their prognosis, patients were categorized into two groups: pNETs G1/G2 group and pNETs G3/pNECs group. Results: A total of 42 patients who underwent surgery (n = 38) or biopsy (n = 4) and had histopathologically confirmed pNETs were included. According to the WHO 2019 criteria, all pNETs were classified into grade 1 (G1, n = 10), grade 2 (G2, n = 21), or grade 3 (G3)/pancreatic neuroendocrine carcinomas (pNECs) (n = 11), based on the Ki−67 proliferation index and the mitotic activity. The majority of the TICs (27/31) of pNETs G1/G2 were above or equal to those of pancreatic parenchyma in the arterial phase, but most (7/11) pNETs G3/pNECs had TICs below those of pancreatic parenchyma from arterial phase to late phase (p < 0.05). Among all the CEUS quantitative parameters of DCE-US, values of relative rise time (rPE), relative mean transit time (rmTT) and relative area under the curve (rAUC) were significantly higher in pNETs G1/G2 group than those in pNETs G3/pNECs group (p < 0.05). Taking an rPE below 1.09 as the optimal cut-off value, the sensitivity, specificity and accuracy for prediction of pNETs G3/pNECs from G1/G2 were 90.91% [58.70% to 99.80%], 67.64% [48.61% to 83.32%] and 85.78% [74.14% to 97.42%], respectively. Taking rAUC below 0.855 as the optimal cut-off value, the sensitivity, specificity and accuracy for prediction of pNETs G3/pNECs from G1/G2 were 90.91% [66.26% to 99.53%], 83.87% [67.37% to 92.91%] and 94.72% [88.30% to 100.00%], respectively. Conclusions: Dynamic contrast-enhanced ultrasound analysis might be helpful for predicting the pathological grades of pNETs. Among all quantitative parameters, rPE, rmTT and rAUC are potentially useful parameters for predicting G3/pNECs with aggressive behavior. [ABSTRACT FROM AUTHOR]

Cyanobacteria are globally important primary producers and abundant in many iron-limited aquatic environments. The ways in which they take up iron are largely unknown, but reduction of Fe3+ is an important step in the process. Here we report a special iron permease in Synechocystis, cFTR1, that is required for Fe3+ uptake following Fe2+ re-oxidation. The expression of cFTR1 is induced by iron starvation, and a mutant lacking the gene is abnormally sensitive to iron starvation. The cFTR1 protein localizes to the plasma membrane and contains the iron-binding motif 'REXXE'. Point-directed mutagenesis of the REXXE motif results in a sensitivity to Fe-deficiency. Measurements of iron (55Fe) uptake rate show that cFTR1 takes up Fe3+ rather than Fe2+. The function of cFTR1 in Synechocystis could be genetically complemented by the iron permease, Ftr1p, of Saccharomyces cerevisiae, that is known to transport Fe3+ produced by the oxidation of Fe2+ via a multicopper oxidase. Unlike yeast Ftr1p, cyanobacterial cFTR1 probably obtains Fe3+ primarily from the oxidation of Fe2+ by oxygen. Growth assays show that the cFTR1 is required during oxygenic, photoautotrophic growth but not when oxygen production is inhibited during photoheterotrophic growth. In cyanobacteria, iron reduction/re-oxidation uptake pathway may represent their adaptation to oxygenated environments. [ABSTRACT FROM AUTHOR]

Summary: For an elementary study in vitro of probiotics with aid of antioxidant property for ameliorating oxidative stress, Lactobacillus pentosus subsp. FS4722, Lactobacillus plantarum subsp. FS5062, FS5382 and FS5498 were used to evaluate their antioxidant property via chemical‐based and cellular assays. A significant dose‐dependent manner was observed in the results of DPPH, ·OH and ·O2− radical‐scavenging activity. Principal component analysis (PCA), however, showed that the total antioxidant activity of four Lactobacillus was positively associated with their ability against H2O2‐induced HepG2 cell death, which indicated Lactobacillus pentosus FS4722 (95.07 ± 5.08%) had great potential for repairing oxidative damage in HepG2 cells oxidative stress model. The potential regulatory pathway of Lactobacillus FS4722 antioxidant action is reduction of intracellular ROS levels, improvement of SOD and CAT enzymes activities along with the activation of Nrf2 signalling and upregulation of the transcription levels of antioxidant factors NQO1, GCLG, GCLM and HO‐1. [ABSTRACT FROM AUTHOR]

Ammonia lyases have great application potential in food and pharmaceuticals owing to their unique ammonia addition reaction and atom economy. A novel methylaspartate ammonia-lyase, Ec MAL, from E. coli O157:H7 showed high catalytic activity. To further strengthen its thermostability and activity, disulfide bond and backbone cyclization (cyclase) variants were constructed by rational design, respectively. Among them, variant M3, with a disulfide bond introduced, exhibited a 2.3-fold increase in half-life at 50 °C, while cyclase variant M8 showed better performance, with 25.9-fold increases. The synergistic promotion effect of this combinational strategy on activity and stability was also investigated, and the combined mutant M9 exhibited a 1.1-fold improvement in catalytic efficiency while maintaining good thermostability. Circular dichroism analysis and molecular dynamics simulation confirmed that the main sources of improved thermostability were reduced atomic fluctuation and a more stable secondary structure. To our knowledge, this is the first example of combining the introduction of disulfide bonds with cyclase construction to improve enzyme stability, which was characterized by modification away from the enzyme active center, and provided a new method for adjusting enzyme thermostability. [Display omitted] • Methylaspartate ammonia lyase was thermostability enhancement for the first time. • Dual-strategy combination to improve the thermostability of enzyme. • Simultaneous improvements in catalytic efficiency and thermostability. • The thermostability improvement mechanism was analyzed using MD simulation and CD. [ABSTRACT FROM AUTHOR]

Millettia Speciosa Champ (M. speciose) is an important medicinal plant applied for multiple disease treatments, however, the polysaccharide composition in M. speciose is rarely investigated. In this study, the structural features and immunomodulatory activities of a polysaccharide (MSCP1) from M. speciose were studied. Results suggested that MSCP1, with a molecular weight of 9.36 × 103 g/mol, consisted of glucose and xylose at a molar ratio of 1.31: 0.01. The glycosidic bond types and linkage manners were successfully elucidated by methylation and multi-dimensional nuclear magnetic resonance spectroscopy. The backbones of MSCP1 were composed of 1,4-linked- α - D -Glc p , 1,4-linked- α - D -Xyl p and 1,4,6-linked- β - D -Glc p. The branch chain T-linked- α - D -Glc p was confirmed to be attached at C-6 of 1,4,6-linked- β - D -Glc p. An in vitro cell assay demonstrated that MSCP1 could prominently enhance the pinocytic activity and up-regulate the release of nitric oxide (NO) and cytokines in RAW 264.7 macrophages, implying a potent immunomodulatory activity. Overall, MSCP1 exhibits characteristics that qualify it as a promising candidate for immunologic adjuvant. • A novel polysaccharide MSCP1 was obtained from Millettia Speciosa Champ. • The glycosidic bond types and linkage manners were successfully elucidated. • MSCP1 exhibited a strong immunomodulatory effect in RAW 264.7 cells. • The underlying structure-function relationship was clarified. [ABSTRACT FROM AUTHOR]

[Display omitted] • The terminology of bionanozyme was conceptualized. • Three Zn-heptapeptide bionanozymes with nanofibrous architecture were assembled. • Zn-heptapeptide bionanozymes exhibited favorable hydrolase-like activity towards p -nitrophenyl esters. • Zn-heptapeptide bionanozymes were applied for degradation of di(2-ethylhexyl) phthalate (DEHP). Nanozyme with intrinsic enzyme-like activity has emerged as favorite artificial catalyst during recent years. However, current nanozymes are mainly limited to inorganic-derived nanomaterials, while biomolecule-sourced nanozyme (bionanozyme) are rarely reported. Herein, inspired by the basic structure of natural hydrolase family, we constructed 3 oligopeptide-based bionanozymes with intrinsic hydrolase-like activity by implementing zinc induced self-assembly of histidine-rich heptapeptides. Under mild condition, divalent zinc (Zn2+) impelled the spontaneous assembly of short peptides (i.e. Ac-IHIHIQI-CONH 2 , Ac-IHIHIYI-CONH 2 , and Ac-IHVHLQI-CONH 2), forming hydrolase-mimicking bionanozymes with β -sheet secondary conformation and nanofibrous architecture. As expected, the resultant bionanozymes were able to hydrolyze a serious of p -nitrophenyl esters, including not only the simple substrate with short side-chain (p -NPA), but also more complicated ones (p -NPB, p -NPH, p -NPO, and p -NPS). Moreover, the self-assembled Zn-heptapeptide bionanozymes were also proven to be capable of degrading di(2-ethylhexyl) phthalate (DEHP), a typical plasticizer, showing great potential for environmental remediation. Based on this study, we aim to provide theoretical references and exemplify a specific case for directing the construction and application of bionanozyme. [ABSTRACT FROM AUTHOR]