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Light-fueled self-oscillators based on soft actuating materials have triggered novel designs for small-scale robotic constructs that self-sustain their motion at non-equilibrium states and possess bioinspired autonomy and adaptive functions. However, the motions of most self-oscillators are reciprocal, which hinders their use in sophisticated biomimetic functions such as fluidic transportation. Here, an optically powered soft material strip that can perform nonreciprocal, cilia-like,self-sustained oscillation under water is reported. The actuator is made of planar-aligned liquid crystal elastomer responding to visible light. Two laser beams from orthogonal directions allow for piecewise control over the strip deformation, enabling two self-shadowing effects coupled in one single material to yield nonreciprocal strokes. The nonreciprocity, stroke pattern and handedness are connected to the fluidic pumping efficiency, which can be controlled by the excitation conditions. Autonomous microfluidic pumping in clockwise and anticlockwise directions, translocation of a micro-object by liquid propulsion, and coupling between two oscillating strips through liquid medium interaction are demonstrated. The results offer new concepts for non-equilibrium soft actuators that can perform bio-like functions under water.

Light-fueled self-oscillators based on soft actuating materials have triggered novel designs for small-scale robotic constructs that self-sustain their motion at non-equilibrium states and possess bioinspired autonomy and adaptive functions. However, the motions of most self-oscillators are reciprocal, which hinders their use in sophisticated biomimetic functions such as fluidic transportation. Here, we report an optically powered soft material strip that can perform non-reciprocal, self-sustained oscillation under water. The actuator is made of planar-aligned liquid crystal elastomer responding to visible light. Two laser beams from orthogonal directions allow for piecewise control over the strip deformation, enabling two self-shadowing effects coupled in one single material to yield non-reciprocal strokes. The non-reciprocity, stroke pattern and handedness are connected to the fluidic pumping efficiency, which can be controlled by the excitation conditions. We demonstrate autonomous microfluidic pumping in clockwise and anticlockwise directions, translocation of a micro-object by liquid propulsion, and coupling between two oscillating strips through liquid medium interaction. The results can offer new concepts for non-equilibrium soft actuators that can perform bio-like functions under water. This article is protected by copyright. All rights reserved.

Searching for dense subgraphs is the crux of a variety of graph mining applications. It is also meaningful to investigate problems of finding local dense subgraphs related to particular nodes, especially for large real-world graphs. However, none of the problems focus on maximizing the average degrees of the found subgraphs. We formulate the MDS-N problem, which aims to find such a subgraph with the maximum average degree, near or containing a given node in an undirected graph. We propose the Slither algorithm and the Slither PageRank (PR) algorithm, built on a reduction from the MDS-N problem to the minimum conductance problem and the Lovasz-Simonovits Theorem of random walks. A simple hierarchically repetition frame is also proposed to advance the two algorithms. Experiments conducted on both unipartite graphs and bipartite graphs show the effectiveness, stability, and scalability of our algorithms. Additionally, we verify the MDS-N problem and the proposed algorithms on a large social network Twitter, the experimental results of which show our algorithms can successfully detect local fraud-related subgraphs based on particular fraudulent user accounts.

Geopolymers can be transformed into zeolites under certain synthesis conditions. However, zeolite formation is not frequently reported in KOH-activated geopolymers. This study attempted to explore zeolite synthesis through geopolymerization for a curing time of 24 h using mixed NaOH/KOH alkaline solution as an activator, and then applying the geopolymer-supported zeolites to immobilize Cd(II) in paddy soil. The K2O/M2O–H2O/SiO2 and K2O/M2O–OH–/SiO2 binary zeolite crystallization phase diagrams were obtained. Zeolite A, faujasite and sodalite formed at lower K2O/M2O molar ratios (0–0.2), ferrierite formation was favoured at a K2O/M2O molar ratio of 0.2–0.4 and zeolite K-I and zeolite F-K (both K-zeolites) were observed at a K2O/M2O molar ratio of 0.6. The geopolymer-supported zeolites had micropores and mesopores and specific surface area values of 44.2–74.8 m2 g–1. The material displayed a considerable Cd(II) immobilization efficiency (55.6–58.7% at 4–6 wt.% addition of zeolite).

Introduction Dehydration has been considered as a potential contributor to vertical root fractures (VRFs) after root canal treatment (RCT). A loss of water could cause embrittlement of dentin and detrimental shrinkage strains. Senior patients have the highest risk of VRF. In this study, we characterized the spatial distribution in shrinkage of tooth roots with respect to donor age and prior RCT. Methods Single-rooted human teeth with and without prior RCT were collected from young (age 60 years) adults. Transverse slices were sectioned from the apical, middle, and coronal thirds of the roots, and digital image correlation was used to evaluate shrinkage during free convection. Crack initiation and growth analysis was performed via optical microscopy, and bound water in dentin was characterized by Raman spectroscopy. Results The rate of shrinkage was significantly higher (p ≤ .05) in the apical third than in the middle and coronal thirds of all teeth regardless of donor age. The highest shrinkage strain occurred in the apical third of old donor teeth with prior RCT. In addition, the RCT-treated old teeth suffered the highest percentage of water loss with dehydration. Cracks initiated from the root surface and extended toward the canal with loss of water and shrinkage. Conclusions The apical third undergoes significantly larger shrinkage strains with dehydration than the remainder of the root. Prior RCT exacerbates the extent of shrinkage, particularly in the teeth of seniors and after clinical function, which could increase the propensity for VRF.

The bamboo-based composite sheet (BCS) based on sustainable theory was designed to improve the utilization of bamboo waste as well as provide a green and renewable product in the surface decoration field. The influence of color, width, proportion for BCS was studied to develop a preparation technology. The perception evaluation (aesthetic value and emotional characteristics) of BCS was analyzed. These results showed when the bamboo proportion was at a low level (10%), the perception evaluation of BCS was almost unaffected by the color and width of bamboo waste. As the bamboo proportion increased constantly, BSC gave a stronger feeling of lively, traditional and warm. The BCS with thin bamboo waste gave a sense of clean and regularity. On the contrary, the BCS with thick bamboo waste was more suitable for creating a dynamic and radical environment. The BCS with yellow bamboo waste gave a feeling of exquisite, modern, and warm, while green bamboo waste gave a sense of unordered, robust, traditional, and cold.

The Y3Si2C2 coating on the surface of the silicon carbide powders can play as an important additive to improve the sintering process of silicon carbide ceramics. A detailed thermodynamic description for the Y-Si-C system is desired to study the sintering and densification mechanisms. Coupling the first-principles calculations and CALPHAD approach, we have thermodynamically investigated the Y-Si-C with its binary sub-systems. The presently obtained thermodynamic parameters can reasonably reproduce the available experimental data. With the theoretical analysis, we have successfully elaborated the thermal behaviors of the Y3Si2C2 coating during the sintering process. Similar work on other SiC based systems may provide a solid thermodynamic basis for the development of other sintering aids in ceramics.

As an addition to the iron-carbon alloys to improve their strength and corrosion resistance, copper is of great importance for iron and steel industry and the Fe–Cu–C system has been extensively investigated. Aiming at a thermodynamic basis to investigate the effect of Cu addition on the Fe–C system, the CALPHAD (CALculation of PHAse Diagrams) approach was utilized to assess the ternary Fe–Cu–C system including the binary Cu–C and Fe–C systems. The Redlich-Kister model, instead of the Modified Quasichemical Model (MQM) in previous work, was used to model the liquid phase. The parameters of the liquid phase in the Fe–C system from previous work have been slightly modified to fit better with new experimental data at high temperatures. One Fe/Cu/FeC0.05 (in wt%) diffusion couple was designed to further determine the phase equilibria of the ternary system. A set of self-consistent parameters for the Fe–Cu–C system was obtained after thermodynamic optimization. Good correspondence between calculated and experimental values of phase diagrams, thermodynamic properties, and liquidus projections has been achieved by the present thermodynamic description.

Ti?Al based alloys have been widely used in the aeronautics and aerospace. Adding alloying element Zr can significantly improve their high-temperature endurance and corrosion resistance. To investigate the influence of the addition of element Zr on the properties of the Ti?Al system, ab initio calculations and the CALPHAD (CALculation of PHAse Diagrams) method were used to evaluate the Ti?Al?Zr ternary system. Ab initio calculations were carried out to calculate the formation enthalpies of intermetallic compounds and end-members. CALPHAD approach was employed to optimize the thermodynamic parameters based on experiments. The experimental data of phase equilibria at 1073, 1273, 1473, and 1573 K, as well as a vertical section of the Ti3Al?Ti + 5 wt.% Zr were used to assess this system. The thermodynamic parameters of the binary Ti?Al, Al?Zr and Ti?Zr systems were acquired from recent assessments, and the ternary ones were evaluated in the present work. The Ti?Al?Zr ternary dataset has been established and the calculated results are in close agreement with the experimental data on both thermodynamics and phase equilibria.

Semicarbazide-sensitive amine oxidase (SSAO) activity is known to be associated with certain pathologies including diabetes. In this study, SSAO expression and enzymatic activity in blood plasma of healthy rats were significantly upregulated under simulated microgravity (SMG) condition. Significant mortality was observed in SMG group of diabetic rats. Results indicate that microgravity might increase the risks of SSAO-associated alterations.

This work investigated the effect of cooling rate (water quenching and air cooling) on the precipitation of ω phase after solution treatment in β-phase region, and its effect on the mechanical properties in a novel metastable β titanium alloy (Ti–5Mo–3Cr–Fe–3Zr). The initial microstructures, phase composition and deformation-induced microstructures have been investigated using SEM, EBSD, XRD, and TEM. The phase composition of water-quenched alloy and air-cooled alloy are β, α", and ω phase. The size and volume fraction of ω phase of air-cooled alloy are larger than that of water-quenched alloy, resulting in an increase in tensile strength and a decrease in ductility. Deformation mechanisms of Ti–5Mo–3Cr–Fe–3Zr alloy with different cooling rate change from stress-induced ω phase transformation and dislocation slip to only dislocation slip. The stress-induced ω lamellas parallel to [1-11]β direction along the [0001]ω1 direction, which is formed by {112}β β slip. Dislocations can cut through the encountered ω phase to form ω-free deformation bands, which accounts for the ductility.

Crowdsourcing receives massive vote information from non-expert workers, for finishing tasks that can hardly be handled by current technology of machine intelligence. Massive vote information and non-expert workers bring serious issues of labor costs and the efficiency of crowdsourcing. This paper focuses on the tasks, classifying objects in images or videos into a set of given candidates by letting workers vote on a set of options that characterize these candidates. Designing a good asking strategy, i.e., setting up the order of presenting the options to a worker and asking the worker whether an option is true or false, is one starting point to save labor costs and enhance efficiency of deciding the correct answer from the candidates. We propose the problem of determining the time steps of vote collection before stopping to set up the asking strategy. In terms of this problem, we establish a single-step collection based partially observable Markov decision process (POMDP) to analyze how a vote influences the whole system, for instance, influences the belief over each option. Formally define the multistep collection problem as the timed decision (TD) problem. We propose the MC-EVA algorithm based on Monte Carlo sampling to solve the TD problem. Evaluate the MC-EVA algorithm over three simple but typical cases and a real-world Galaxy Zoo 2 project. Experiments show MC-EVA’s great superiority in runtime over the state-of-the-art single-step collection algorithm, and its superiority in effectiveness than other multistep collection algorithms; show its labor cost saving and enhanced efficiency with the use of calculated asking strategies.

A new water-responsive photonic coating based on a hygroscopic amphoteric poly(ampholyte) has been developed. The material consists of an interpenetrating network between the poly(ampholyte) and a cholesteric liquid crystalline polymer that reflects light. Swelling of this hybrid material upon contact with water causes a red-shift of the reflection band. As both cation and anion are incorporated in the ionic network, this coating possesses a high stability of its water responsiveness after prolonged and/or repeated exposure to water, even if the water contains dissolved ions. In addition, optimization of the water response of the coatings is demonstrated by changing the composition of the base cholesteric mixture, and color patterns were prepared through selective UV exposure.

Long-term spaceflight has always been challenging for astronauts due to the extremely complicated space environmental conditions, including microgravity, noise, confinement, and circadian rhythms disorders, which may cause adverse effects on astronauts' mental health, such as anxiety and depression. Unfortunately, so far, the underlying mechanism is not fully understood. Hence, a novel type of box and rat cage was designed and built in order to simulate complex space environment on the ground. After earth-based simulation for 21 days, the rats exhibited the depressive-like behavior according to the sucrose preference and forced swimming test. We applied label-free quantitative proteomics to explore the molecular mechanisms of depressive-like behavior through global changes in cortical protein abundance, given that the cortex is the hub of emotional management. The results revealed up-regulated spliceosome proteins in contrast to down-regulated oxidative phosphorylation (OXPHOS), glutamatergic, and GABAergic synapse related proteins in the simulated complex space environment (SCSE) group. Furthermore, PSD-95 protein was found down-regulated in mass spectrometry, reflecting its role in the psychopathology of depression, which was further validated by Western blotting. These findings provide valuable information to better understand the mechanisms of depressive-like behavior. Significance Quantitative proteomic analysis can quantify differentially abundant proteins related to a variety of potential signaling pathways in the rat cortex in the simulated complex space environment. These findings not only provide valuable information to better understand the mechanisms of depressive-like behavior, but also might offer the potential targets and develop countermeasures for the mental disorders to maintain the health of astronauts during the long-term spaceflight.

Using simulators is a cost-effective way to meet human needs. Nevertheless, inevitable errors derived from the gap between simulation and the real world sometimes cause great losses and must be taken seriously. This paper focuses on one cause of the gap, which is the incomplete state representation in simulation, and proposes a supervised learning approach, correcting human-unacceptable policies calculated by simulators, based on human feedback. The approach first detects the related blind spots by classifiers which are trained on data from aggregation of noisy human feedback. Then, it corrects the human-unacceptable policies through the complementary model presented based on linear function approximation (LFA) and a policy iteration algorithm FRU-SADPP that uses radial basis functions (RBFs). We evaluate our approach on two simulated domains and demonstrate its higher accuracy of policies than two baselines, in terms of three typical kinds of human suboptimality and human errors, and three types of human feedback. Experiments also show the scalability of our approach.

Wear degradation is a key parameter to evaluate the performance of ceramic-metal composites applied in manufacturing and mining industries. We selected a typical composite (high Mn steel + 50 wt.% TiC) as the model system and studied its wear behavior. The integrity and damage of TiC ceramic particles were analyzed under different temperatures and atmospheres. A critical temperature of ~125 °C at which transitions of wear mechanism occurred was observed for the first time. Below this temperature, hardness dominated the wear behavior as the presence of oxygen induced surface decarburization of ceramic particles with an increased wear rate. The thermodynamics of oxygen-assisted decarburization were investigated using the CALPHAD (CALculation of PHAse Diagram) approach, and the resultant hardness reduction of TiC particles was clarified using density functional theory (DFT) calculations. At temperatures above 125 °C, toughness became the governing factor as the ceramic-metal deformation incompatibility induced fracture of ceramic particles. The formation of nano-crystalline oxide tribolayers improved the fracture toughness of ceramic particles and restrained the wear loss, which was elucidated using DFT calculations. Thus, the current work has delineated the competitive micro-mechanisms consisting of surface decarburization and toughening of ceramic particles, which could be used to interpret the wear behavior of ceramic-metal composites.

Background An elevated serum uric acid level has often been observed with type 2 diabetes or cancer progression. This study aimed to investigate the association between the serum uric acid, cancer incidence, and mortality in Chinese patients with type 2 diabetes. Methods A total of 8274 patients with type 2 diabetes from the Shanghai Diabetes Registry (SDR) participated. The follow-up rate was 85.4%. All subjects were divided into four groups according to the serum uric acid concentration: group 1 (1.0 mg/dL ≤ SUA

To predict the thermal behaviors of Dy3Si2C2 during sintering or joining process of the silicon carbide (SiC) ceramics, we established a detailed thermodynamic description of Dy–Si–C by coupling the first-principles calculations and the CALPHAD (CALculation of PHAse Diagram) approach. First-principles calculations were applied to acquire the formation enthalpies of key compounds, which can perform as end-members during optimization. We proposed a first Dy–C binary phase diagram referred to other RE-C (RE = La, Ce and Pr) systems. The Dy–Si system, previously described with the modified quasichemical model (MQM), was modeled based on the random-mixing Bragg Williams model in this work. The presently obtained thermodynamic parameters can reasonably reproduce the available experimental data and elucidate the thermal behaviors of Dy3Si2C2. We calculated that Dy3Si2C2 reacted with SiC via ternary eutectic reaction at 1432 °C, which was consistent with the reported experimental results. Further work of other SiC-based systems may provide foresight to explore new sintering aids in ceramics.

Multifactorial evolutionary algorithm (MFEA) exploits the parallelism of population-based evolutionaryalgorithm and provides an efficient way to evolve individuals for solving multiple tasks concurrently.Its efficiency is derived by implicitly transferring the genetic information among tasks.However, MFEA doesn?t distinguish the information quality in the transfer compromising the algorithmperformance. We propose a group-based MFEA that groups tasks of similar types and selectivelytransfers the genetic information only within the groups. We also develop a new selection criterionand an additional mating selection mechanism in order to strengthen the effectiveness andefficiency of the improved MFEA. We conduct the experiments in both the cross-domain and intra-domainproblems.

The goal of the present study was to explore the correlations of 1,5-anhydroglucitol (l,5-AG), glycated hemoglobin (HbA1c), and glycated albumin (GA) with insulin sensitivity and secretion.In total, 302 patients with newly diagnosed type 2 diabetes mellitus (166 men, 136 women) were enrolled in this study. The homeostasis model assessment for insulin resistance (HOMA-IR) and homeostasis model assessment for β-cell function (HOMA-β) were calculated to determine the basal insulin sensitivity and secretion. The insulinogenic index (IGI) was used to evaluate early-phase insulin secretion. 1,5-AG and GA were assayed via the enzymatic method, and HbA1c was detected by high-pressure liquid chromatography.Among all 302 subjects, the serum 1,5-AG level was 13.1±7.2 μg/mL, and the HbA1c and GA levels [median (interquartile range)] were 6.7% (6.2-7.3%) and 17.7% (16.0-19.5%), respectively. Increased 1,5-AG quartiles were accompanied by trends toward a decreased HOMA-IR and an increased HOMA-β and IGI (for all trends, P0.001). 1,5-AG was negatively associated with HOMA-IR (r=-0.200, P0.001) and positively associated with HOMA-β and IGI (r=0.210 and 0.413, respectively; both P0.001). 1,5-AG was independently related to HOMA-IR and HOMA-β and exhibited an independent positive association with IGI (standardized β=0.242, P0.001). Additionally, both HbA1c and GA were independently correlated with HOMA-IR and HOMA-β.1,5-AG is not only correlated with basal insulin sensitivity and secretion, but also closely associated with early-phase insulin secretion in Chinese patients with newly diagnosed type 2 diabetes mellitus.

Dyslipidemia is commonly seen in patients with type 2 diabetes mellitus (T2DM). The current study sought to compare the effects of nateglinide and acarbose, two antihyperglycemic agents, on both fasting and postprandial lipid profiles in Chinese subjects with T2DM.For this multicenter, open-label, randomized, active-controlled, parallel-group study, 103 antihyperglycemic agent-naive patients with T2DM were recruited from four hospitals in China. In total, 85 subjects (44 in the nateglinide group, 41 in the acarbose group) with a known complete lipid profile underwent the entire clinical trial and were included in the final analysis. Serum was collected in the fasting state and 30 and 120 min after a standardized meal (postprandial states) to measure the baseline lipid profiles; the same testing was performed upon completion of a 2-week course of nateglinide (120 mg three times a day) or acarbose (50 mg three times a day).Fasting triglyceride (TG) levels were significantly reduced by both nateglinide and acarbose (P0.001), with acarbose providing a significantly more robust improvement (vs. nateglinide, P=0.005). Additionally, the TG levels at both postprandial times were significantly reduced by acarbose (P0.001 at 30 min and P=0.002 at 120 min), whereas nateglinide treatment only significantly reduced the 30-min postprandial TG (P=0.029). Neither nateglinide nor acarbose treatment had significant impact on total cholesterol, high-density lipoprotein, low-density lipoprotein, or non-high-density lipoprotein cholesterol.Compared with nateglinide, acarbose has superior therapeutic efficacy for reducing fasting and postprandial TG levels in patients with T2DM.