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Shot peening is one of the most powerful mechanical peening techniques applied in surface engineering to improve the mechanical properties of metal alloys by introducing compressive residual stresses. During shot peening process, surface integrity, such as microstructures, surface roughness, hardness and residual stress can be varied by adjusting the operating parameters of shot peening. To facilitate the understanding of the microstructure and properties variation, in our latest work, shot peening with high coverage percentage has been employed to create severe plastic deformation on stainless steel 304 (SUS304). Morphological and topological study on the shot peened coupons were carried out using microscopes and 3D optical profiler. Residual stress depth profiling was evaluated using X-ray diffraction technique. Microstructures, phase distribution and crystal orientation were analyzed by electron backscatter diffraction technique. The results show that phase transition γ - α’ and grain refinement occur during this mechanical peening process. A nanocrystalline layer with preferred orientation formed near the surface, and dislocations accumulated within sub-surface area, which can be attributed to the high energy input from the peening process. The maximum compressive residual stress, which is around 1000-1200 MPa, occurred beneath the top surface. All these findings will provide guideline for surface engineering at various scales and designing of the surface enhancement process via mechanical peening for achieving optimum surface integrity of metallic alloys.

Single-crystal Sc2Mo3O12 nanofibers, an one-dimensional negative thermal expansion (NTE) material, have been successfully synthesized by electrospinning. The crystal structure, morphology, and NTE ...

The exact prevalence of mirror syndrome remains unclear, and the precise clinical features need to be disclosed. We retrospectively reviewed 85 cases of foetal hydrops from a total of 98,484 deliveries. Of these 16 showed mirror syndrome, while 69 did not. The incidence of mirror syndrome among all deliveries was 0.0162%, while that among patients with foetal hydrops was 23.2%. Maternal symptoms of mirror syndrome included anaemia (

Ligand-induced chirality in semiconducting nanocrystals has been the subject of extensive study in the past few years and shows potential applications in optics and biology. Yet, the origin of the chiroptical effect in semiconductor nanoparticles is still not fully understood. Here, we examine the effect of the interaction with amino acids on both the fluorescence and the optical activity of chiral semiconductor quantum dots (QDs). A significant fluorescence enhancement is observed for l/d-Cys-CdTe QDs upon interaction with all the tested amino acids, indicating suppression of nonradiative pathways as well as the passivation of surface trap sites brought via the interaction of the amino group with the CdTe QDs’ surface. Heterochiral amino acids are shown to weaken the circular dichroism (CD) signal, which may be attributed to a different binding configuration of cysteine molecules on the QDs’ surface. Furthermore, a red shift of both CD and fluorescence signals in l/d-Cys-CdTe QDs is only observed upon adding cysteine, while other tested amino acids do not exhibit such an effect. We speculate that the thiol group induces orbital hybridization of the highest occupied molecular orbital (HOMOs) of cysteine and the valence band of CdTe QDs, leading to the decrease of the energy band gap and a concomitant red shift of CD and fluorescence spectra. This is further verified by density functional theory calculations. Both the experimental and theoretical findings indicate that the addition of ligands that do not “directly” interact with the valence band (VB) of the QD (noncysteine moieties) changes the QD photophysical properties, as it probably modifies the way cysteine is bound to the surface. Hence, we conclude that it is not only the chemistry of the amino acid ligand that affects both CD and PL but also the exact geometry of binding that modifies these properties. Understanding the relationship between the QD’s surface and chiral amino acid thus provides an additional perspective on the fundamental origin of induced chiroptical effects in semiconductor nanoparticles, potentially enabling us to optimize the design of chiral semiconductor QDs for chiroptic applications.

We studied the morphological and crystallographic properties of Ni-based single-crystal superalloys, addressing their surface and near-surface structural evolutions upon robotic hammer peening (RHP) by employing surface profiling, X-ray diffraction, scanning electron microscopy, and electron backscatter diffraction. By varying the diameter (DHH) of the spherical hammer head and the driving pressure (PRHP), we found that the RHP process with the increased DHH and PRHP tends to improve the surface smoothness and, meanwhile, reduce the RHP-induced step height at the boundary between the peened and unpeened areas, especially on the surface with a deformed layer caused by wire electrical discharge machining (EDM). The surface step height can also be reduced by removing the EDM-deformed layer before the RHP process. Straight and crosshatching DSTs were observed in the transition zones surrounding the peened area, where none or minor crystal reorientations occurred. In comparison, the RHP-induced crystal reorientation is much more significant in the peened area and the reorientation direction is associated with the surface normal direction, i.e., the compression loading axis of the RHP process. The RHP-induced crystal reorientations are discussed and attributed to the non-Schmid behavior associated with multiple cross-slips of superalloys under dynamic compressive loadings.

Background: Salvia miltiorrhiza polyphenolic acid (SMPA) is effective in the treatment of cardiovascular diseases and currently it is administered orally or intravenously. However, SMPA is poorly absorbed orally and quickly eliminated in vivo. A long-term frequent intravenous administration leads to poor patient compliance. Therefore, it is urgently demanded to find a new alternative route of noninjection drug delivery system for SMPA. Methods: Two dry powder inhalation (DPI) formulations of spray-dried SMPA formulation (P1) and spray-dried SMPA-L-leucine formulation (P2) were prepared by spray drying method and their physicochemical properties were assessed by thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, particle size distribution analysis, and in vitro aerodynamic analysis. Moreover, In vitro cytotoxicity of SMPA and P2 was conducted with NR8383 cells. In vivo pharmacokinetics were carried out by Penn-Century endotracheal intubation technique to deliver P2 to the lungs of rats. Results and Conclusions: The moisture content of P1 and P2 were 5.81% ± 0.005%, and 4.08% ± 0.002%, respectively. P1 and P2 were in an amorphous state. Moreover, P1 had slightly corrugated surfaces, whereas P2 exhibited severely corrugated surfaces with invagination due to the presence of L-leucine. In addition, there were more hollow particles with smooth surface in P1 than that in P2. Compared with P1, P2 has shown optimal physical particle size and aerosolization behavior with D (v, 50) of 2.64 ± 0.01 μm and fine particle fraction of 37.55% ± 2.63%. The findings of in vitro cytotoxicity showed that P2 did not inhibit cell viability and could be safe for pulmonary administration. The absolute bioavailability of salvianolic acid B (Sal B) for pulmonary administration was 19.15% ± 7.44%, which is significantly higher than the oral bioavailability of Sal B (

Co-precipitation was successfully applied to synthesize the Sc3+ doped In2-xScx (WO4)3 (x = 0, 0.3, 0.6, 0.9 and 1.2) compounds. The composition- and temperature-induced structural phase transition and thermal expansion behaviors of Sc3+ doped In2(WO4)3 were investigated. Results indicate that In2-xScx (WO4)3 crystalizes in a monoclinic structure at 300 °C for x ≤ 0.3 and changes into hexagonal structure for x ≥ 0.6. Hexagonal In1.1Sc0.9(WO4)3 displays negative thermal expansion (NTE) with an average linear coefficient of thermal expansion (CTE) of −1.85 × 10−6 °C −1. After sintering at 700 °C and above, a phase transition from hexagonal to orthorhombic phase was observed in In2-xScx (WO4)3 (x ≥ 0.6). Sc3+ doping successfully reduce the temperature-induced phase transition temperature of In2-xScx (WO4)3 ceramics from 250 °C (x = 0) to room temperature (x = 0.9). When x = 0.9 and 1.2, the average linear CTEs of In2-xScx (WO4)3 ceramics are −5.45 × 10−6 °C−1 and -4.43 × 10−6 °C−1 in a wider temperature range of 25–700 °C, respectively.

Monitoring of water oxidation by the established Co cubane catalyst Co4O4(OAc)4(py)4 (abbrev. Co4O4, OAc = acetate, py = pyridine) by time-resolved rapid-scan ATR FT-IR spectroscopy revealed the O–...

We studied the effect of robotic hammer peening (RHP) on plastic deformation, martensite transformation, and electrochemical process of austenitic stainless steels (SS304L) by employing microscopy and X-ray diffraction (XRD) characterizations. By changing the stepover distance dStep in a range of 0.1-2.0 mm we found that onset of surface plastic deformation at the center areas between adjacent grooves (i.e., those induced by RHP along the longitudinal feeding direction) occurs at dStep

Mesenchymal stem cells are a promising source of regenerative cells, and have been used for clinical cell therapy in recent years. Their widespread application originates from established potency in a broad range of experimental animal models and believable safety profile in humans. Acute lung injury/acute respiratory distress syndrome are common and potentially lethal diseases characterized by acute respiratory failure due to noncardiogenic pulmonary edema, excessive pulmonary inflammation, and alveolar-capillary barrier disruption. Despite tremendous research concerning the pathophysiology of acute lung injury, its death rate remains high and seldom efficacious pharmacotherapy exists. Mesenchymal stem cells participate in related mechanisms through paracrine effects by inducing other cells or regulating certain pro-inflammatory and anti-inflammatory factors, and have the trend for re-epithelization and repairment in lung injury by transplanting ability. The paracrine effects of mesenchymal stem cells in these pathways are the current research hotspot by releasing soluble bioactive factors to interact with damaged tissues. Mesenchymal stem cells secrete a broad range of cytokines, growth factors, chemokines, and miRNAs through microvesicles or exosomes to protect endogenous cells, attenuate the inflammatory response and inhibit apoptosis, which may be the therapeutic basis of their application in acute lung injury. Therefore, it is vital to study the effects of mesenchymal stem cells and revealing their mechanisms at the cellular and molecular levels. Their transplantation and differentiation capabilities, as well as the paracrine effects provide pre-clinical basis to prevent and treat acute lung injury/acute respiratory distress syndrome. Several clinical trials have been administrated and mesenchymal stem cells have promising prospects as therapeutic drugs for lung diseases.

Two decades after the rapid expansion of photovoltaics, the number of solar panels reaching end-of-life is increasing. While precious metals such as silver and copper are usually recycled, silicon, which makes up the bulk of a solar cells, goes to landfills. This is due to the defect- and impurity-sensitive nature in most silicon-based technologies, rendering it uneconomical to purify waste silicon. Thermoelectrics represents a rare class of material in which defects and impurities can be engineered to enhance the performance. This is because of the majority-carrier nature, making it defect- and impurity-tolerant. Here, the upcycling of silicon from photovoltaic (PV) waste into thermoelectrics is enabled. This is done by doping 1% Ge and 4% P, which results in a figure of merit (zT) of 0.45 at 873 K, the highest among silicon-based thermoelectrics. The work represents an important piece of the puzzle in realizing a circular economy for photovoltaics and electronic waste. Agency for Science, Technology and Research (A*STAR) Ministry of National Development (MND) National Environmental Agency (NEA) A.S. acknowledges funding from A*STAR (Agency of Science, Technology and Research) Career Development Fund (CDF) no. C210112022. J.X acknowledges A*STAR “Sustainable Hybrid Lighting System for Controlled Environment Agriculture programme”: A19D9a0096. Z.L. would also like to express gratitude to the financial support from the A∗STAR’s Science and Engineering Research Council (SERC) Central Research Fund (Use-inspired Basic Research) for this work. N.M. and Q.Y. acknowledge grant award from NEA (National Environmental Agency, Singapore) and Ministry of National Development (MND, Singapore) titled “Singapore–CEA Alliance for Research in Circular Economy (SCARCE, award number USS-IF-2018-4),” which is a joint lab set up between Nanyang Technological University (NTU, Singapore) and the French Alternative Energies and Atomic Energy Commission (CEA, France).

Aiming at the inevitably offset phenomenon in the cold rolling process of aluminum strip, this paper introduces the automatic width measurement and centering scheme based on machine vision. With the Raspberry Pi as the main control unit, each frame of picture is processed through median filtering and Canny edge detection algorithm to obtain the edge pixel coordinates on both sides of the aluminum sheet, which are then converted to the world coordinate system to obtain its actual position. Calculate the width of the aluminum sheet via Ethernet communication to the main control computer; at the same time, calculate the offset of the aluminum sheet relative to the rolling line, and use the PID algorithm to control the hydraulic servo system of the uncoiling reducer to achieve closed-loop centering control. The actual measurement shows that this scheme effectively replaces the tedious operation steps of the console, and has good stability and performance.

Motivation Circular RNA is generally formed by the ‘back-splicing’ process between the upstream splice acceptor and the downstream donor in/not in the regulation of the corresponding RNA-binding proteins or cis-elements. Therefore, more and more software packages have been developed and they are mostly based on the identification of the back-spliced junction reads. However, recent studies developed two software tools that can detect circRNA candidates by constructing k-mer table or/and de Bruijn graph rather than reads mapping. Results Here, we compared the precision, sensitivity and detection efficiency between software tools based on different algorithms. Eleven representative detection tools with two types of algorithm were selected for the overall pipeline analysis of RNA-seq datasets with/without RNase R treatment in two cell lines. Precision, sensitivity, AUC, F1 score and detection efficiency metrics were assessed to compare the prediction tools. Meanwhile, the sensitivity and distribution of highly expressed circRNAs before and after RNase R treatment were also revealed by their enrichment, unaffected and depleted candidate frequencies. Eventually, we found that compared to the k-mer based tools, CIRI2 and KNIFE based on reads mapping had relatively superior and more balanced detection performance regardless of the cell line or RNase R (-/+) datasets. Availability and implementation All predicted results and source codes can be retrieved from https://github.com/luffy563/circRNA_tools_comparison. Supplementary information Supplementary data are available at Bioinformatics online.

Structure engineering strategies such as core-shell and hollow nanostructures are effective pathways to improve the utilization of noble metals for catalysis. However, nowadays materials design based on these strategies still largely rely on precious metal templates. Herein, the epitaxial growth of highly crystalline Pt

Increasing nitrogen (N) deposition severely impacts terrestrial biogeochemical cycles by altering the stoichiometry of ecological components. Although microbes are known to play an important role in biogeochemical cycles, the mechanisms how soil microbes drive nutrient cycling remain elusive under N deposition. Therefore, we investigated changes in microbial community diversity, composition, and interactions, and elucidated the relationship among microbial community responses, soil available nutrients, and ecological stoichiometry resulting from two years of N addition to a Pinus tabuliformis plantation on the Loess Plateau at four rates of N addition (0 (N0), 3.0 (N3), 6.0 (N6), and 9.0 (N9) g N m−2 y−1). N addition significantly influenced microbial composition, decreasing the relative abundance of Acidobacteria and Basidiomycota along N addition gradients and increasing the relative abundance of Ascomycota from N3 to N9. Along N addition gradients except N3, bacterial interactions increased from 62.70% to 73.38%, whereas interactions between bacterial and fungal communities decreased from 34.44% to 24.43%. Among all microbial interactions, the positive ones accounted for a larger proportion (over 55%), indicating a predominance of mutualism under all N addition treatments. Changes in the microbial composition were correlated with soil resource stoichiometry factors, including soil organic carbon: soil total N (SOC:TN) and SOC: soil total phosphorus (SOC:TP), whereas the topological network features were correlated with ammonium N (NH4+-N), nitrate N (NO3−-N), β-1,4-N-acetylglucosaminidase (NAG), alkaline phosphatase (AP), and eco-enzymatic stoichiometry. Therefore, the soil variables that caused changes to microbial composition and interactions were different. In this sense, microbial community compositions were more easily affected by soil resource stoichiometry, whereas microbial interactions were more easily affected by soil available nutrients. In addition, changes to microbial interactions could mediate microbial metabolism via eco-enzyme expression.

Doping of tin disulfide (SnS2) is an effective strategy to regulate its physical and chemical properties. In this work, In doping was used to manipulate the photoresponse behavior of SnS2-based pho...

The Naruo porphyry Cu deposit is the third largest deposit discovered in the Duolong metallogenic district. Previous research has focused mainly on the geochemistry of the ore-bearing granodiorite porphyry; the metallogenesis remains poorly understood. In the present work, on the basis of outcrops and drilling core geological mapping, phases of early mineralization diorite, two inter-mineralization granodiorite porphyries, and late-mineralization granodiorite porphyry have been distinguished. Furthermore, the alteration zones were outlined, and the vein sequence was identified. The diorite and three porphyry phases were subjected to Laser Ablation Inductively Coupled Plasma Mass Spectrometry (La–ICP–MS) zircon U–Pb dating and in situ Hf isotope analyses as well as bulk major element, trace element, and Sr–Nd isotopic analyses. Molybdenite Re–Os dating was also conducted. The zircon U–Pb dating results show that the diorite and porphyry intrusions were emplaced at about 120 Ma, and the molybdenite Re–Os isochron age is 118.8 ± 1.9 Ma; this indicates that the Naruo porphyry Cu deposit was formed during a continuous magmatic–hydrothermal process. All of the diorite and granodiorite porphyry samples showed arc magmatic characteristics. Moreover, the moderate ( 87 Sr/ 86 Sr) i ratios and low e Nd(t) and e Hf(t) values of the diorite and porphyry intrusions suggest the source region of the juvenile lower crust. The lower ( 87 Sr/ 86 Sr) i and ( 143 Nd/ 144 Nd) i ratios and higher e Nd(t) values and incompatible element concentrations than those in the granodiorite porphyry samples indicate a two-stage magmatic generation process for the intrusions. The early mineralization diorite has a high Cu concentration, implying that the source is enriched in Cu. However, the slightly lower Cu content of the late-mineralization granodiorite porphyry samples might imply Cu release from magmas and deposition within the metallogenic stage. The multiple stages of intrusions and subsequent volcanism within the Duolong metallogenic district, together with high Sr/Y features, indicate persistent magmatism during the metallogenic epoch, which is necessary for maintaining the activity of magmatic–hydrothermal and mineralization processes. Thus, the high Cu content in the source region, mantle-derived melt upwelling, and multiple stages of persistent magmatism were favorable for the formation of the Naruo porphyry Cu deposit. The high Fe 2 O 3 /FeO ratios of the diorite and granodiorite porphyry intrusions show very high oxidation features, which is coincident with estimated magmatic oxidation state calculated by the zircon trace element compositions. The high oxidation facilitates sulfur and chalcophile metals to be scavenged into the magmatic–hydrothermal systems, which is crucial for the metallogenesis of the Naruo porphyry Cu deposit.

Our research examines the effectiveness of monetary compensation and the promptness of response during electronic word-of-mouth (eWOM)-triggered service recovery. Drawing upon restorative justice theories, we explore three main questions: whether the hotel's response to negative online reviews are always beneficial; whether offering compensation or responding promptly is more efficient under different levels of service failure severity; and how the hotel's response influences consumers' future engagement through eWOM media. Experimental results reveal that making minimum online service recovery effort is only effective in fixing consumer attitudes for less severe service failures. Compensation is the optimal solution for less severe failures, while prompt response is optimal for more severe service failures. The hotel's responsiveness to negative reviews and the service recovery outcome positively influence consumers' future eWOM behaviours through the same online medium. Implications for hotels seeking cost-effective management of negative reviews and for online media owners are offered.

Robust electronic transport properties is a crucial in designing high performance thermoelectrics. A key similarity between superconductor and thermoelectric lies in their generally high electrical conductivity, even at above its superconducting temperature. In this work, we design a nanocomposite between Nb

Recombinant human interferon α-2b (rhINF-α-2b), like most proteins, has several shortcomings such as relatively short half-life, low therapeutic index, high circulating drug fluctuations, and rapid degradation which could hinder its effective delivery. Novel electrostatic spray and ion exchange drug-loading techniques were combined to formulate rhINF-α-2b sodium hyaluronate cross-linked porous sustained-release microspheres (rhINF-α-2b-SHCPM), a protein delivery system. The different properties of rhINF-α-2b-SHCPM including the physicochemical nature, in vitro release behavior, and antitumor activity were evaluated. The loading rate (10.31 ± 0.94%) and encapsulation efficiency (89.09 ± 2.37%) of rhINF-α-2b-SHCPM produced acceptable values. The in vitro cumulative release rate of rhINF-α-2b-SHCPM within 24 h was also 86.26 ± 2.11% with a much better sustained release effect. Thus, the half-life (10.763 h) and retention time (14.067 h) of rhIFNα-2b-SHCPM were significantly prolonged with enhanced bioavailability (43,198.387 ng/L*h) and decreased peak concentration (15,266.4 ngL

‘Superfoods’ have become a popular diet style across the globe but are also criticized as a marketing gimmick. Despite the controversy, the essential drivers of superfood consumption and advocacy remain underexplored. Drawing upon the theory of consumption values and prospect theory, this study explores how consumers’ value perceptions of superfoods influence their behavioral responses (i.e., repurchase and positive word-of-mouth intentions) by introducing the concept of relative advantage in food consumption. Based on a survey sample of 447 superfood consumers and structural equation modeling, our findings identify relative advantage as an important mediator in the cognitive process that converts consumers’ value perceptions into behavioral re-sponses. We also find buffering effects of perceived costs in the relationship between relative advantage and repurchase behavior. This research advances the understanding of consumers’ modern food consumption habits and lifestyles and has important implications for academics, marketing practitioners and policy makers.

Ranitidine hydrochloride (RH) resinates were prepared by bath method using a highly acidic cation-exchange resin as the carrier. The drug-resinates combination pattern was characterized by DSC and X-ray diffraction. The influences of the types of the ion-exchange resin, initial RH concentration and the reaction temperature on the process of ion exchange were investigated. Three empirical kinetics models and thermodynamics equations were studied to the ion exchange process under different temperatures. The results showed that RH combined with ion-exchange resin not simple physical mixture but by ion bond, and the rate of ion exchange increased on increasing the initial drug concentration and reducing the temperature the resin. The in vitro drug release test showed that the release process was affected by the kind of countra-ion, ionic strength and temperature. Thermodynamics results showed that the ion exchange reaction between RH and cation-exchange resin was exothermic (ΔH

The High Energy X-ray telescope (HE) on-board the Hard X-ray Modulation Telescope (\textit{Insight}-HXMT) can serve as a wide Field of View (FOV) gamma-ray monitor with high time resolution ($\mu$s) and large effective area (up to thousands cm$^2$). We developed a pipeline to search for Gamma-Ray Bursts (GRBs), using the traditional signal-to-noise ratio (SNR) method for blind search and the coherent search method for targeted search. By taking into account the location and spectrum of the burst and the detector response, the targeted coherent search is more powerful to unveil weak and sub-threshold bursts, especially those in temporal coincidence with Gravitational Wave (GW) events. Based on the original method in literature, we further improved the coherent search to filter out false triggers caused by spikes in light curves, which are commonly seen in gamma-ray instruments (e.g. \textit{Fermi}/GBM, \textit{POLAR}). We show that our improved targeted coherent search method could eliminate almost all false triggers caused by spikes. Based on the first two years of \textit{Insight}-HXMT/HE data, our targeted search recovered 40 GRBs, which were detected by either \textit{Swift}/BAT or \textit{Fermi}/GBM but too weak to be found in our blind search. With this coherent search pipeline, the GRB detection sensitivity of \textit{Insight}-HXMT/HE is increased to about 1.5E-08 erg/cm$^2$ (200 keV$-$3 MeV). We also used this targeted coherent method to search \textit{Insight}-HXMT/HE data for electromagnetic (EM) counterparts of LIGO-Virgo GW events (including O2 and O3a runs). However, we did not find any significant burst associated with GW events., Comment: 12 pages, 14 figures, 5 tables; accepted for publication in MNRAS