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Despite the clear association between remnant cholesterol (RC)and diabetes risk, no study to date has examined the relationship between RC and reversal of prediabetes to normoglycemia. This retrospective cohort study included a total of 15,023 patients with prediabetes who underwent a physical examination between 2010 and 2016. The link between initial RC levels and the reversion from prediabetes to normoglycemia was analyzed using the Cox proportional-hazards regression model. Additionally, the study explored the possible relationship between RC and the probability of returning normoglycemia by applying Cox proportional hazards regression models with cubic spline functions. To address competing risks, a multivariate Cox regression analysis was undertaken, treating the onset of diabetes as a competing risk event for reversing prediabetes to normoglycemia. Additionally, the study incorporated extensive subgroup analyses alongside multiple sensitivity analyses, enhancing the reliability and robustness of the results. After adjusting for covariates, the findings indicated that RC was inversely associated with the likelihood of reverting to normoglycemia (per 5 mg/dL increase, HR = 0.918, 95% CI 0.909–0.927). The analysis also revealed a nonlinear relationship between RC and normoglycemia reversion, with an inflection point at 51.08 mg/dL. For RC values below this inflection point (RC < 50.08 mg/dL), the HR for the probability of returning to normoglycemia was 0.907 (95% CI 0.897–0.917 per 5 mg/dL). Additionally, the competing risks model demonstrated a negative relationship between RC and the reversal of prediabetes to normoglycemia (SHR = 0.92, 95% CI 0.91–0.93). Sensitivity analyses confirmed the robustness and stability of these results. This study demonstrated a negative and non-linear association between RC and the probability of reversion to normoglycemia in Chinese adults with prediabetes. By actively intervening to reduce RC levels, at least to below 51.08 mg/dL, further reduction of RC may significantly increase the probability of returning to normoglycemia from prediabetes. [ABSTRACT FROM AUTHOR]

Inspired by “Lotus effect” and “Petal effect” from nature, superhydrophobic materials have become a hot spot in recent years. However, the researches on these materials still face great challenges. Herein, the superhydrophobic material with transition between “Lotus effect” and “Petal effect” is fabricated via a facile strategy. In the preparation, the organosilicon polymer acts as the matrix, while modified nano-CaCO3 (M-CaCO3) and hydrophobic nano-SiO2 (H-SiO2) act as the dispersed phase, to construct the superhydrophobic material (OSiP–Ca–Si). Through regulating the ratio of M-CaCO3 and H-SiO2, the wetting properties of materials can be controlled for the transition between “Lotus effect” and “Petal effect”. For the materials with different effects, both of the water contact angles (WCAs) are above 150∘C, while the slide angles (SAs) are 4∘C and 180∘C, respectively. The transition mechanism can be explained by the distinct microstructures and the roughness they caused due to the different compositions. It is demonstrated that the material with “Lotus effect” possesses an outstanding self-cleaning function, and the material with “Petal effect” can well be applied in water harvesting. Therefore, this work provides a facile strategy for designing the superhydrophobic material with transition between “Lotus effect” and “Petal effect”, and endows them with different applications, thus exhibiting great significance in the advancement of superhydrophobic materials. [ABSTRACT FROM AUTHOR]

Research on the adoption of IoT technology in the global chilled beverages industry is limited. The outbreak of the COVID-19 pandemic had a substantial impact on chilled beverage sales and disrupted the operations of organizations within this industry. In order to navigate the challenges posed by this "new normal," the implementation of IoT adoption strategies becomes increasingly vital. We conducted semi-structured interviews with 19 leaders representing 14 chilled beverage companies across five continents, following the Gioia methodology. Our study findings shed light on the critical role of operational efficiency and organizational capability in the successful adoption of IoT technology. By focusing on these aspects, our study aims to contribute to the seamless integration of IoT technology into the chilled beverages industry. To align with this goal, we propose an innovative IoT adoption framework tailored to support managers in navigating this understudied topic. [ABSTRACT FROM AUTHOR]

After decades of development, LIDAR and visual SLAM technology has relatively matured and been widely used in the military and civil fields. SLAM technology enables the mobile robot to have the abilities of autonomous positioning and mapping, which allows the robot to move in indoor and outdoor scenes where GPS signals are scarce. However, SLAM technology relying only on a single sensor has its limitations. For example, LIDAR SLAM is not suitable for scenes with highly dynamic or sparse features, and visual SLAM has poor robustness in low-texture or dark scenes. However, through the fusion of the two technologies, they have great potential to learn from each other. Therefore, this paper predicts that SLAM technology combining LIDAR and visual sensors, as well as various other sensors, will be the mainstream direction in the future. This paper reviews the development history of SLAM technology, deeply analyzes the hardware information of LIDAR and cameras, and presents some classical open source algorithms and datasets. According to the algorithm adopted by the fusion sensor, the traditional multi-sensor fusion methods based on uncertainty, features, and novel deep learning are introduced in detail. The excellent performance of the multi-sensor fusion method in complex scenes is summarized, and the future development of multi-sensor fusion method is prospected. [ABSTRACT FROM AUTHOR]

Surface defect inspection is a key technique in industrial product assessments. Compared with other visual applications, industrial defect inspection suffers from a small sample problem and a lack of labeled data. Therefore, conventional deep-learning methods depending on huge supervised samples cannot be directly generalized to this task. To deal with the lack of labeled data, unsupervised subspace learning provides more clues for the task of defect inspection. However, conventional subspace learning methods focus on studying the linear subspace structure. In order to explore the nonlinear manifold structure, a novel neural subspace learning algorithm is proposed by substituting linear operators with nonlinear neural networks. The low-rank property of the latent space is approximated by limiting the dimensions of the encoded feature, and the sparse coding property is simulated by quantized autoencoding. To overcome the small sample problem, a novel data augmentation strategy called thin-plate-spline deformation is proposed. Compared with the rigid transformation methods used in previous literature, our strategy could generate more reliable training samples. Experiments on real-world datasets demonstrate that our method achieves state-of-the-art performance compared with unsupervised methods. More importantly, the proposed method is competitive and has a better generalization capability compared with supervised methods based on deep learning techniques. [ABSTRACT FROM AUTHOR]

• BDOC promoted the dehydrochlorination of 1,1,2,2-tetrachloroethane in basic solution. • Synergies of dipole-dipole and conjugate bases was the dominant catalysis mechanism. • The promoting effect was enhanced at a higher pH by forming more conjugate bases. • >1 kDa fraction of BDOC presented greater promoting effect than <1 kDa fraction. • N-containing species and aromatic protein-/polyphenol-like matters played key roles. The environmental effects of biochar-derived organic carbon (BDOC) have attracted increasing attention. Nevertheless, it is unknown how BDOC might affect the natural attenuation of widely distributed chloroalkanes (e.g., 1,1,2,2-tetrachloroethane (TeCA)) in aqueous environments. We firstly observed that the kinetic constants (k e) of TeCA dehydrochlorination in the presence of BDOC samples or their different molecular size fractions (<1 kDa, 1∼10 kDa, and >10 kDa) ranged from 9.16×103 to 26.63×103 M−1h−1, which was significantly greater than the k e (3.53×103 M−1h−1) of TeCA dehydrochlorination in the aqueous solution at pH 8.0, indicating that BDOC samples and their different molecular size fractions all could promote TeCA dehydrochlorination. For a given BDOC sample, the kinetic constants (k e) of TeCA dehydrochlorination in the initial pH 9.0 solution was 2∼3 times greater than that in the initial pH 8.0 solution due to more formation of conjugate bases. Interestingly, their DOC concentration normalized kinetic constants (k e /[DOC]) were negatively correlated with SUVA 254 , and positively correlated with A 220 /A 254 and the abundance of aromatic protein-like/polyphenol-like matters. A novel mechanism was proposed that the C H dipole of BDOC aliphatic structure first bound with the C Cl dipole of TeCA to capture the TeCA molecule, then the conjugate bases (-NH-/-NH 2 and deprotonated phenol-OH of BDOC) could attack the H atom attached to the β-C atom of bound TeCA, causing a C Cl bond breaking and the trichloroethylene formation. Furthermore, a fraction of >1 kDa had significantly greater k e /[DOC] values of TeCA dehydrochlorination than the fraction of <1 kDa because >1 kDa fraction had higher aliphiticity (more dipole-dipole sites) as well as more N-containing species and aromatic protein-like/polyphenol-like matters (more conjugate bases). The results are helpful for profoundly understanding the BDOC-mediated natural attenuation and fate change of chloroalkanes in the environment. [Display omitted] [ABSTRACT FROM AUTHOR]

In industrial processes, stiction in control valves is a common cause of degradation in control loop performance. It is important to identify and establish reliable stiction models to enhance control loop performance. This study focuses on constructing a precise model of the pneumatic control valve using the LuGre friction model. To improve the model, a smooth function based on probability density is introduced to alleviate the LuGre friction model. The maximum error resulting from this smoothing process is also analyzed. To estimate the valve stiction parameters, the direct transcription method is utilized to convert the problem from systems of ordinary differential equations into a nonlinear programming problem. The interior point method is then used to solve this problem. Furthermore, the estimability of the parameters is analyzed based on the reduced Hessian matrix before estimation. Numerical results demonstrate that the proposed approach in this study effectively estimates the stiction parameters of pneumatic control valves. • LuGre model is used to describe the friction in the control valve. • Probability density function based approach is introduced to smooth the LuGre model for gradient-based algorithm. • Stiction parameters of control valve are estimated by collocation method and error introduced by smoothing is also evaluated. • The results show that the predicted stem positions with the estimated parameters fit the measurements with high accuracy. [ABSTRACT FROM AUTHOR]

Visual SLAM (VSLAM) has been developing rapidly due to its advantages of low-cost sensors, the easy fusion of other sensors, and richer environmental information. Traditional visionbased SLAM research has made many achievements, but it may fail to achieve wished results in challenging environments. Deep learning has promoted the development of computer vision, and the combination of deep learning and SLAM has attracted more and more attention. Semantic information, as high-level environmental information, can enable robots to better understand the surrounding environment. This paper introduces the development of VSLAM technology from two aspects: traditional VSLAM and semantic VSLAM combined with deep learning. For traditional VSLAM, we summarize the advantages and disadvantages of indirect and direct methods in detail and give some classical VSLAM open-source algorithms. In addition, we focus on the development of semantic VSLAM based on deep learning. Starting with typical neural networks CNN and RNN, we summarize the improvement of neural networks for the VSLAM system in detail. Later, we focus on the help of target detection and semantic segmentation for VSLAM semantic information introduction. We believe that the development of the future intelligent era cannot be without the help of semantic technology. Introducing deep learning into the VSLAM system to provide semantic information can help robots better perceive the surrounding environment and provide people with higher-level help. [ABSTRACT FROM AUTHOR]

Because of the broad application of human action recognition technology, action recognition has always been a hot spot in computer vision research. The Long Short-Term Memory (LSTM) network is a classic action recognition algorithm, and many effective hybrid algorithms have been proposed based on basic LSTM infrastructure. Although some progress has been made in accuracy, most of those hybrid algorithms have to have more and more complex structures and deeper network levels. After analyzing the structure of the classic LSTM from the perspective of control theory, we determined that the classic LSTM could strengthen the differential characteristics of human action recognition technology to reflect the change of speed. Thus, an improved LSTM structure with an input differential characteristic module is proposed. Furthermore, in this article, we considered the influence of first-order and second-order differential on the extraction of movement pose information, that is, the influence of movement speed and acceleration on action recognition. We designed four different LSTM units with first-order and second-order differential. Moreover, the experiments were performed for the four units on three common datasets repeatedly. We found that the LSTM network with the input differential feature module proposed in this article can effectively improve action recognition accuracy and stability without deepening the complexity of the network and can be used as a new basic LSTM network architecture. [ABSTRACT FROM AUTHOR]

The deposition of biomass-burning smoke water-soluble organic matter (BBS-WSOM) significantly affects the environmental behavior of heavy metals in aqueous environments. However, the interactions between BBS-WSOM and heavy metals at the molecular level remain unknown. This study combined FT-ICR-MS, fluorescence spectrum, FTIR, and two-dimensional correlation spectroscopy to anatomize the molecular characteristics of BBS-WSOM binding with Cd(II). The results show that CHO and CHOP compounds were responsible for the fluorescence response of BBS-WSOM at Ex: 225 nm and 275 nm/Em: 325 nm, and abundant proteins or CHON compounds were responsible for the fluorescence response of BBS-WSOM at Ex: 225–250 nm/Em: 350–450 nm and Ex: 300–350 nm/Em: 350–450 nm, which was very different from the fluorescence molecules in natural organic matters. Fluorescence change after Cd(II) addition indicated that CHOP and CHOS compounds enhanced BBS-WSOM binding with Cd(II). Differently, the CHON compounds could weaken the binding of other compounds with Cd(II). Different compounds binding with Cd(II) generally followed the order: CHON/CHOS compounds>CHOP compounds>CHO compounds, and the chemical groups binding with Cd(II) generally followed the prioritization: -COO-> -NH/S O>P = O/P-O>aromatic ring>C O>C-OH of phenol/alcohol>C-O-C. This study provides a profound insight into the interaction between BBS-WSOM and Cd(II) at the molecular level. [Display omitted] • BBS-WSOM had very different fluorescence molecular compositions from natural DOM. • CHOP and CHOS compounds enhanced BBS-WSOM binding with Cd(II). • CHON compounds could weaken CHO/CHOP compounds to bind with Cd(II). • CHOP/CHON/CHOS compounds binding with Cd(II) were prior to CHO compounds. • Different chemical groups binding with Cd(II) had different prioritization. [ABSTRACT FROM AUTHOR]

Time delay is a ubiquitous phenomenon in chemical engineering. In the development of a practical rigorous model for process system, the influence of time delay cannot be ignored. A simultaneous approach for estimating time delays and model parameters is proposed in this work. The critical issue is how to address the approximation for state variable with time delay, which depends on the quotient and remainder obtained by dividing time delay by length of finite element. The strategies for handling the unknown quotient and remainder are designed. Finally, two case studies are considered. The effectiveness of the proposed approach is verified. Moreover, the proposed approach exhibits better performance compared with the gradient-based sequential approach. • Both time-delays and model parameters are estimated for nonlinear systems with simultaneous approach. • Discretization for the state variables with time delays are designed based on the length of finite element. • Remainder of time-delay divided by finite element length is handled based on conditional expression and smoothing function. • A heuristic strategy is proposed to decrease the influence of discretization error on the accuracy of parameter estimation. • Much less computational cost is needed by the proposed approach compared with the gradient based sequential approach. [ABSTRACT FROM AUTHOR]

BACKGROUND Barley grass (BG) powder has gradually attracted researchers' attention for its abundant nutritional components and functional activity. Yet, the effect of different drying methods on storage stability is still unclear. In this study, BG was subjected to hot‐air drying (HAD), steam blanching prior to hot‐air drying (SHAD), vacuum freeze drying (VFD), and far‐infrared drying (FID). Effects of different drying methods on BG powder during storage were evaluated. RESULTS: Moisture content of dried samples during storage decreased at 50 °C, but at 37 °C increased first and then remained stable. The a* value of SHAD BG powder before storage was the highest (−6.51), followed by FID, HAD and VFD. Moreover, the a* value increased during the storage process. Contents of l‐ascorbic acid and total chlorophyll in samples dried by VFD were 28.29 and 7.8 g kg−1, respectively. The degradation of chlorophyll a and b followed a first‐order kinetics model and was modeled by the Arrhenius equation. The activation energies for chlorophyll a were 83.68, 83.21, 62.29 and 76.64 kJ mol−1 in BG powder dried by SHAD, FID, VFD and HAD, respectively. The activation energies for chlorophyll b were 66.76, 48.03, 61.02 and 58.01 kJ mol−1 in SHAD, FID, VFD and HAD BG powder, respectively. CONCLUSION: VFD had the highest preservation of color, l‐ascorbic acid and chlorophyll compared to HAD, SHAD and FID. SHAD shortened the drying time and delayed the degradation of l‐ascorbic acid and chlorophyll during storage. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Idiopathic achalasia (IA) is a severe motility disorder characterized by neuronal degeneration in the myenteric plexus, but the etiology remains largely unknown. We performed whole-exome sequencing (WES) in 100 IA-affected individuals and 313 non-IA control subjects and validated the results in 230 IA-affected individuals and 1,760 non-IA control subjects. Common missense variants rs1705003 (CUTA , GenBank: NC_000006.11:g.33385953A>G) and rs1126511 (HLA-DPB1 , GenBank: NC_000006.11:g.33048466G>T) at 6p21.32 were reproducibly associated with increased risk of IA (rs1126511: OR = 1.83, p = 2.34 × 10−9; rs1705003: OR = 2.37, p = 3.21 × 10−7), meeting exome-wide significance. Both variants can affect the expression of their target genes at the transcript level. An array-based association analysis in 280 affected individuals and 1,121 control subjects determined the same signal at 6p21.32. Further conditional analyses supported that the two missense variants identified in WES-based association study were potential causal variants of IA. For rare variants, the top genes identified by gene-based analysis were significantly enriched in nerve and muscle phenotypic genes in the mouse. Moreover, the functional rare variants in these genes tended to cooccur in IA-affected individuals. In an independent cohort, we successfully validated three rare variants (CREB5 , GenBank: NC_000007.13:g.28848865G>T; ESYT3 , GenBank: NC_000003.11:g.138183253C>T; and LPIN1 , GenBank: NC_000002.11:g.11925128A>G) which heightens the risk of developing IA. Our study identified and validated two common variants and three rare variants associated with IA in immunologic and neurological genes, providing new insight into the etiology of IA. [ABSTRACT FROM AUTHOR]

• Phosphate significantly enhanced GO transport in saturated porous media. • Enhanced role was due to electrostatic repulsion and deposition site competition. • Enhancement effect in goethite-coated sand was to a larger extent than that in sand. • Cation-bridging promoted the enhancement effects in the presence of Ca2+. In this study, transport behaviors of graphene oxide (GO) in saturated uncoated (i.e., clean sand) and goethite-coated sand porous media were examined as a function of the phosphate. We found that phosphate enhanced the transport of GO over a wide range of solution chemistry (i.e., pH 5.0–9.0 and the presence of 10 mmol/L Na+ or 0.5 mmol/L Ca2+). The results were mainly ascribed to the increase of electrostatic repulsion between nanoparticles and porous media. Meanwhile, deposition site competition induced by the retained phosphate was another important mechanism leading to promote GO transport. Interestingly, when the phosphate concentration increased from 0.1 to 1.0 mmol/L, the transport-enhancement effect of phosphate in goethite-coated sand was to a much larger extent than that in clean sand. The observations were primarily related to the difference in the total mass of retained phosphate between the iron oxide-coated sand and clean sand columns, which resulted in different degrees of the electrostatic repulsion and competitive effect of phosphate. When the background solution contained 0.5 mmol/L Ca2+, phosphate could be bind to sand/ goethite-coated sand surface by cation bridging; and consequently, promoted competition between phosphate and nanoparticles for deposition sites, which was an important mechanism for the enhanced effect of phosphate. Moreover, the DLVO theory was applicable to describe GO transport behaviors in porous media in the absence or presence of phosphate. Taken together, these findings highlight the important status and role of phosphate on the transport and fate of colloidal graphene oxide in the subsurface environment. [Display omitted] [ABSTRACT FROM AUTHOR]

Biochar as an effective adsorbent can be used for the removal of triclocarban from wastewater. Biochar-derived dissolved organic carbon (BC-DOC) is an important carbonaceous component of biochar, nonetheless, its role in the interaction between biochar and triclocarban remains little known. Hence, in this study, sixteen biochars derived from pine sawdust and corn straw with different physico-chemical properties were produced in nitrogen-flow and air-limited atmospheres at 300–750 °C, and investigated the effect of BC-DOC on the interaction between biochar and triclocarban. Biochar of 600∼750 °C with low polarity, high aromaticity, and high porosity presented an adsorption effect on triclocarban owing to less BC-DOC release as well as the strong π-π, hydrophobic, and pore filling interactions between biochar and triclocarban. In contrast and intriguingly, biochar of 300∼450 °C with low aromaticity and high polarity exhibited a significant solubilization effect rather than adsorption effect on triclocarban in aqueous solution. The maximum solubilization content of triclocarban in biochar-added solution reached approximately 3 times its solubility in biochar-free solution. This is mainly because the solubilization effect of BC-DOC surpassed the adsorption effect of biochar though the BC-DOC only accounted for 0.01–1.5 % of bulk biochar mass. Furthermore, the high solubilization content of triclocarban induced by biochar was dependent on the properties of BC-DOC as well as the increasing BC-DOC content. BC-DOC with higher aromaticity, larger molecular size, higher polarity, and more humic-like matters had a greater promoting effect on the water-solubility of triclocarban. This study highlights that biochar may promote the solubility of some organic pollutants (e.g., triclocarban) in aqueous environment and enhance their potential risk. [Display omitted] • Biochar of 300∼450 °C improved the solubility of triclocarban, • Biochar of 600∼750 °C presented an adsorption effect on triclocarban, • Solubilization effect of biochar depended on the content and properties of BC-DOC, • Biochar might enhance the mobility and the potential risk of triclocarban. [ABSTRACT FROM AUTHOR]

A facile and effective route to synthesize graphene quantum dots for cell imaging and as a deoxidizer by using glucan as a precursor is developed. AuNPs are successfully synthesized by mixing of graphene quantum dots and Au(III) salts without any additional reductants. The reducing driving force of these graphene quantum dots is much weaker than that of strong reducing agents such as NaBH4. The sizes of the as-synthesized AuNPs are much larger, with an average size of 15 nm. Notably, this size range is specifically useful and optimal for the application of AuNPs in biomedical applications. In addition, the as-synthesized graphene quantum dots are also successfully applied in cell imaging. [ABSTRACT FROM AUTHOR]

A solid‐state electrochemiluminescence (ECL) biosensing switch system based on the specific recognition of an aptamer and the destruction of pyridine ruthenium by ferrocene was successfully developed for the detection of Listeria monocytogenes detections. The switching system consisted of two principal parts, the ECL luminescent substrate and the ECL intensity switch. The ECL luminescent substrate was fabricated by attaching an aptamer of Listeria monocytogenes modified with DNA labeled with bipyridine ruthenium complementary to one end of the aptamer, and ferrocene‐labeled DNA complementary to the other end of the aptamer, to an electrode, and so act as an intensity switch. The identification reaction consisted of the specific binding of the aptamer with Listeria monocytogenes causing the labeled ferrocene to be removed from the luminescent substrate, the structural change resulting in a significant increase in the intensity of ECL due to the decreased quenching effect of ferrocene toward the ECL luminescent substrate. Accordingly, the change in ECL intensity indirectly reflected the concentration of Listeria monocytogenes in the sample. The results demonstrated that the system produced a good linear relationship over the concentration range of 1.4 × 101–1.4 × 106 CFU/ml. The present study established that this was a feasible approach for the detection of Listeria monocytogenes in milk and pork samples. [ABSTRACT FROM AUTHOR]

Graphene quantum dots (GQDs) have aroused widespread attention because of their remarkable properties and potential applications. Herein, we discuss both the top-down and bottom-up strategies for the synthesis of GQDs. Different processes are presented to study their characteristics and the influence on the final properties of GQDs. The respective advantages and disadvantages of these methods are summarized. With regard to some important or novel ones, mechanisms are proposed for reference. In addition, the application of GQDs in biosensors is highlighted in detail. At last, we put forward some problems to be solved and give a brief prospect in their future developments. This review is very useful for quickly gaining knowledge and experience for synthesizing GQDs and designing the related novel biosensors. The latest progresses on the synthesis of GQDs are reviewed. The top-down and bottom-up strategies are discussed comprehensively. The potential application of GQDs in biosensors and their design solution are introduced. A brief outlook and further development for the GQDs are pointed out. This review not only provides a useful guide on the synthesis of GQDs, but also facilitates designing the novel biosensor devices for researchers. [ABSTRACT FROM AUTHOR]

Recently, effective hydrogen (H 2) evolution upon hydrolysis of different hydrogen storage materials has received much attention. Herein, graphene quantum dots-transition metal nanoparticles (GQDs-TMNPs), with high dispersibility and activity, have been successfully applied in the hydrolysis of both NH 3 BH 3 (AB) and NaBH 4 for the first time. GQDs-RhNPs, GQDs-RuNPs, and GQDs-PtNPs are very effective in the hydrolysis of AB and the turnover frequencies (TOFs) can achieve to as high as 656, 384, and 281 mol H2 ·mol cat −1 min−1, respectively. Moreover, the synergistic effect between GQDs and TMNPs is explored, and the mechanisms of catalytic hydrolysis of AB and NaBH 4 by GQDs-TMNPs are proposed. This work not only paves the way for the development of GQDs-TMNPs nanocatalysts for the different hydrogen storage materials, but also further advances the understanding of the synergistic effects between GQDs and TMNPs. Image 1 • GQDs-TMNPs have been firstly applied in the hydrolysis of both AB and NaBH 4. • RhNPs, PtNPs and RuNPs are very efficient for H 2 evolution upon hydrolysis of AB and NaBH 4. • GQDs-TMNPs have been successfully recycled 5 times without significant decrease. [ABSTRACT FROM AUTHOR]

Fatigue crack growth rate (FCGR) tests were used to investigate the fatigue property of low-carbon steel in actual natural gas/hydrogen mixtures and carbon dioxide/hydrogen/nitrogen mixtures. It is found for the first time that the acceleration of FCGRs in the mixtures are much faster than that in hydrogen or natural gas. Natural gas/hydrogen mixtures changed the fracture mode from ductile fatigue striation to brittle cleavage fracture, and restricted the deformation activities around the crack. Synergy effect of carbon dioxide and hydrogen on the material is proposed to be the major reason for the abnormal performance of steel in the mixtures. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The trust and confidence of citizens in their governments has been declining in recent decades. Electronic government (e-government) is seen as a means to reverse this trend. Despite conflicting conclusions in the literature, there is a consensus that e-government-led transformation can improve citizen confidence and trust in government. This research investigates the influence of e-government-led transformation on citizen trust and confidence in the context of a developing country, the Kingdom of Bahrain. A conceptual model is developed, tested and validated using an online survey targeting ordinary citizens of the country. Based on 313 responses, the findings suggest that citizen trust and confidence is positively influenced by a government transformation, and this relationship is mediated by both government performance and citizen satisfaction. In addition, the results show that key factors must be met to achieve transformed government through the use of e-government systems: transparency, accountability, and meeting citizens' expectations. [ABSTRACT FROM AUTHOR]

Fabrication of graphene quantum dots (GQDs) often requires strong acids or organic solvents, and their green synthesises on sustainable routes still face challenges. Herein, an eco‐friendly synthetic process has been developed, in which the natural polymer cellulose has been utilized as a new precursor for the first time. The reaction system is only composed of cellulose and water, in absence of any other chemical reagents. Moreover, the products contain only GQDs, carbide precipitates, and water, leading to easy separation and avoiding complicated post‐processes. In addition, the synthetic mechanism is presented that the formation process of GQDs consists of the first hydrolyzation and the following cyclic condensation. With highly photoluminescent (PL) properties, favourable hydrophilicity, low cytotoxicity and excellent biocompatability, the as‐synthesized GQDs have been successfully applied in bioimaging. This work not only develops a sustainable route for the green synthesis of GQDs, but also finds a renewable resource as the raw material, which significantly facilitates the extensive applications of GQDs in biological fields. An eco‐friendly process for the synthesis of graphene quantum dots (GQDs) has been developed, in which the natural polymer cellulose was utilized as a new precursor for the first time. The synthetic mechanism is presented and the GQDs with high PL emission have been successfully applied in bioimaging. This work not only develops a sustainable route for the green synthesis of GQDs, but also finds a renewable resource as the raw material, significantly facilitating the extensive applications of GQDs in the biological fields. [ABSTRACT FROM AUTHOR]

Abstract Ash in biochar has great influence on the characteristics of biochars. This study systematically compared the differences in physico-chemical properties between pristine biochars (PBCs) and deashed biochars (DBCs) produced at different temperatures (300–900 °C), and specifically analyzed their different advantages in environmental applications. In terms of all the PBCs and DBCs, PBC of 900 °C and the corresponding DBC have the highest degree of graphitization that is recalcitrant in environment, they are benefit for carbon sequestration. PBC of 300 °C and the corresponding DBC have the highest content of O-containing functional groups and aliphaticity that is labile in environment, they are potential carbon source for the growth of soil organisms. PBCs of 300–400 °C have the greatest releasable PO 4 3− content (0.418–0.441 mg/g), and PBCs of 700–900 °C have highest pH (9.28–9.59) and mineral elements content (11.58–12.64 mg/g), they are potential provision of P, and acid soil amendments with potential provision of mineral elements, respectively. DBCs of 300–400 °C possess less competitive cations including Ca, Mg, Al, Fe, and Zn (1.49–2.01 mg/g) and highest content of O-containing functional groups, they are good sorbents for heavy metals, meanwhile these DBCs have the lowest pH (4.49–4.70) that are potential amendments for alkaline soil. Moreover, DBCs of 900 °C have the highest surface area (SA) (351 m2/g), the most developed porosity, and the highest releasable NH 4 + content (0.052 mg/g), they are good sorbents for hydrophobic organic pollutants and potential provision of N. This study gives an effective guidance for selecting the suitable biochars-design (deashing or non-deashing) according to their applications in environment. Graphical abstract Unlabelled Image Highlights • Difference of properties between PBCs and DBCs is related to pyrolysis temperature. • Deashing decrease pH, bulk metal content and releasable PO 4 3− of biochars • Deashing increase SA and releasable NH 4 + of biochars produced at high temperature. • PBCs are benefit for provision of nutrient element. • DBCs are benefit for sorption of pollutants. [ABSTRACT FROM AUTHOR]

Abstract Currently, the role of amorphous carbon structure (ACS) in sorption of chlorinated hydrocarbons (CHs) to biochars remains little known. Therefore, three CHs (1,1,2,2-tetrachloroethane, 1,3,5-trichlorobenzene and γ-hexachlorocyclohexane) with different molecular properties were selected as model adsorbates to investigate the effect of ACS on sorption of CHs to biochars produced at seven different pyrolysis temperatures (300–900 °C). There were two main mechanisms for ACS controlling the sorption of CHs. First, the polar sites on ACS are hydrophilic, CHs with greater polarity could strongly compete with the water molecule for the hydrophilic sites. Second, ACS of low temperature (300–400 °C) produced biochars possessing the natural organic matter (NOM)-like structure occupied some hydrophobic sites on condensed graphitic structure (CGS) of biochars. CHs with great hydrophobicity possibly seized the hydrophobic sorption sites on CGS from the NOM-like structure. Therefore, ACS of biochar was more benefit for sorption of strong polar CHs (1,1,2,2-tetrachloroethane: π∗ = 0.95; Log K ow = 2.39) or strong hydrophobic CHs (1,3,5-trichlorobenzene: π∗ = 0.70; Log K ow = 4.19) than CHs (γ-hexachlorocyclohexane: π∗ = 0.68; Log K ow = 3.72) with relatively low polarity and hydrophobicity. The result reflects that the interaction between NOM and natural black carbon/biochars in soil and water environment possibly plays the similar role in controlling the environmental behavior of various polar or hydrophobic organic pollutants. Moreover, with increasing concentration of adsorbate (C e), the first mechanism enhanced, while the second mechanism weakened. This study gives a deep insight into the roles of ACS of biochars in controlling the fate and availability of CHs with different molecular properties in environment. Graphical abstract Image 1 Highlights • The role of ACS in sorption of biochars is closely related to the molecular properties of CHs. • CHs with greater polarity compete with water molecular for the hydrophilic sites on ACS. • CHs with stronger hydrophobic compete with NOM-like structure for the hydrophobic sites on CGs. • Sorption behavior of CHs on ACS depends on the concentration of CHs. [ABSTRACT FROM AUTHOR]

Maximization of the smallest eigenfrequency of the linearized elasticity system with area constraint is investigated. The elasticity system is extended into a large background domain, but the void is vacuum and not filled with ersatz material. The piecewise constant level set (PCLS) method is applied to present two regions, the original material region and the void region. A quadratic PCLS function is proposed to represent the characteristic function. Consequently, the functional derivative of the smallest eigenfrequency with respect to PCLS function takes nonzero value in the original material region and zero in the void region. A penalty gradient algorithm is proposed, which initializes the whole background domain with the original material and decreases the area of original material region till the area constraint is satisfied. 2 D and 3 D numerical examples are presented, illustrating the validity of the proposed algorithm. [ABSTRACT FROM AUTHOR]

This study was to investigate peanut response to application of nitric oxide (NO) at different growth stages and the effects of NO application on peanut yield and quality in calcareous soil. Sodium nitroprusside (SNP, a NO donor) solution was poured into calcareous soil at sowing, seedling, flowering, and podding stages, respectively, or at each aforesaid critical stage. Results showed that NO application increased the content of active Fe and leaf chlorophyll, which improved the photosynthesis of peanut; enhanced the ability of resistance to oxidative stress by decreased the accumulation of O2•−, H2O2, and MDA and increased the activity of antioxidant enzymes. Nitric oxide increased the content of soil available Fe and root FCR activity, which can promote peanut absorb more Fe from the calcareous soil. What's more, peanut plants may pump a large amount of H+ from root cell membrane to consume in neutralization of HCO3−, and decrease the pH in apoplast, cytoplasm, and xylem, finally balance the mineral elements (Fe, Ca, Mg, Zn, and Cu) uptake and distribution. These results indicated that NO could improve peanut growth and development, increase peanut yield and quality. Furthermore, the application of NO at sowing or seedling stage did the most obvious effect on alleviating chlorosis of peanut in calcareous soil. [ABSTRACT FROM AUTHOR]

A semi-analytical extraction method of interface and bulk density of states (DOS) is proposed by using the low-frequency capacitance--voltage characteristics and current--voltage characteristics of indium zinc oxide thin-film transistors (IZO TFTs). In this work, an exponential potential distribution along the depth direction of the active layer is assumed and confirmed by numerical solution of Poisson's equation followed by device simulation. The interface DOS is obtained as a superposition of constant deep states and exponential tail states. Moreover, it is shown that the bulk DOS may be represented by the superposition of exponential deep states and exponential tail states. The extracted values of bulk DOS and interface DOS are further verified by comparing the measured transfer and output characteristics of IZO TFTs with the simulation results by a 2D device simulator ATLAS (Silvaco). As a result, the proposed extraction method may be useful for diagnosing and characterising metal oxide TFTs since it is fast to extract interface and bulk density of states (DOS) simultaneously. [ABSTRACT FROM AUTHOR]

The surface heterogeneous atoms of carbonaceous materials (CMs) play an important role in adsorption of organic pollutants. However, little is known about the surface heterogeneous atoms of CMs might generate different effect on adsorption of hydrophobic organic compounds by porous carbonaceous materials — activated carbons (ACs) and non-porous carbonaceous materials (NPCMs). In this study, we observed that the surface oxygen and nitrogen atoms could decrease the adsorption affinity of both ACs and NPCMs for 1,1,2,2-tetrachloroethane (TeCA), but the degree of decreasing effects were very different. The increasing content of surface oxygen and nitrogen ([O + N]) caused a sharper decrease in adsorption affinity of ACs (slope of lg ( k d / SA ) vs [O + N]: −0.098∼-0.16) than that of NPCMs (slope of lg ( k d / SA ) vs [O + N]: −0.025∼-0.059) for TeCA. It was due to the water cluster formed by the surface hydrophilic atoms that could block the micropores and generate massive invalid adsorption sites in the micropores of ACs, while the water cluster only occupied the surface adsorption sites of NPCMs. Furthermore, with the increasing concentration of dissolved TeCA, the effect of surface area on adsorption affinity of NPCMs for TeCA kept constant while the effect of [O + N] decreased due to the competitive adsorption between water molecule and TeCA on the surface of NPCMs, meanwhile, both the effects of micropore volume and [O + N] on adsorption affinity of ACs for TeCA were decreased due to the mechanism of micropore volume filling. These findings are valuable for providing a deep insight into the adsorption mechanisms of CMs for TeCA. [ABSTRACT FROM AUTHOR]

Dehydrochlorination of 1,1,2,2-tetrachloroethane (TeCA) in graphene oxide (GO)-based materials-water two-phase system can be enhanced strongly. However, the dehydrochlorination kinetic of adsorbed TeCA on GO-based materials’ surface is still unclear. Thus, in this study the dehydrochlorination kinetics of adsorbed TeCA on GO based-materials’ surface was compared to the kinetics of dissolved TeCA in aqueous solution. The results showed that the dehydrochlorination kinetic constants of adsorbed TeCA on GO-based materials’ surface ( k s_F ) were much greater than those of dissolved TeCA in aqueous solution ( k a ) due to the deprotonated surface oxygen-containing functional groups (e.g. COO − , and O − ) served as conjugated bases to catalyze the reaction. In particular, at pH 8.0 and 9.0, the k s_F values for GO (20 mg/L) were approximately 3 orders magnitude greater than k a values. Furthermore, the k s_F values of adsorbed TeCA for the low concentration of GO (20 mg/L) were always greater than that for the high concentration of GO (100 mg/L). The primary mechanism was that GO was apt to aggregate at high concentration, which enhanced the steric hindrance between O-containing functional groups and TeCA molecular. Consequently, the interfacial effects of GO-based materials at their low concentration could strongly enhance the transformation of adsorbed TeCA in aqueous environment. [ABSTRACT FROM AUTHOR]

Salicylic acid (SA) and nitric oxide (NO), which are known as important signaling molecules in plants, could be promising compounds for the reduction in stress sensitivity. The aim of the present work was to study the physiological changes in peanut (Arachis hypogaea L.) seedlings grown in growth medium that contained 0.1 mM SA, 0.25 mM sodium nitroprusside (SNP, a NO donor), or in full (SA+SNP) or half [1/2 (SA+SNP)] combined strengths under iron (Fe) deficiency. After 21 days of treatment, Fe deficiency significantly inhibited peanut plant growth, destroyed photosynthetic system, and caused oxidative damages. Addition of SA, SNP, and 1/2 (SA+SNP), especially SA+SNP, alleviated the stress, increased the contents of chlorophylls, and promoted plant growth. They improved Fe uptake, transport, and availability in peanut plants by increasing the activities of H+-ATPase and ferric chelate reductase (FCR), and promoting Fe translocation from cell wall to cell organelle and soluble fraction in leaves. Furthermore, they also effectively mitigated oxidative damages by increasing the activities of antioxidant enzymes in peanut leaves and roots. The results from the present study indicate that application of SA, SNP, or 1/2 (SA+SNP) can overcome the adverse effect of Fe deficiency, but the combined application of SA+SNP is more effective in alleviating Fe deficiency stress. [ABSTRACT FROM AUTHOR]

Due to the flexibility of wireless mesh networks (WMNs) to form the backhaul subnetworks, future generation networks may have to integrate various kinds of WMNs under possibly various administrative domains. Aiming at establishing secure access and communications among the communication entities in a multi-domain WMN environment, in this paper, we intend to address the cross-domain authentication and key agreement problem. We present a light-weight cross-domain authentication and key agreement protocol, namely CAKA, under certificateless-based public key cryptosystem. CAKA has a few attractive features. First, mutual authentication and key agreement between any pair of users from different WMN domains can be easily achieved with two-round interactions. Second, no central domain authentication server is required and fast authentication for various roaming scenarios is supported by using a repeated cross-domain algorithm. Third, no revocation and renewal of certificates and key escrow are needed. Finally, it provides relatively more security features without increasing too much overhead of computation and storage. Our analysis shows that the proposed CAKA protocol is highly efficient in terms of communication overhead and resilient to various kinds of attacks. [ABSTRACT FROM AUTHOR]

Parameter estimation of reaction kinetics from spectroscopic data remains an important and challenging problem. This study describes a unified framework to address this challenge. The presented framework is based on maximum likelihood principles, nonlinear optimization techniques, and the use of collocation methods to solve the differential equations involved. To solve the overall parameter estimation problem, we first develop an iterative optimization-based procedure to estimate the variances of the noise in system variables (eg, concentrations) and spectral measurements. Once these variances are estimated, we then determine the concentration profiles and kinetic parameters simultaneously. From the properties of the nonlinear programming solver and solution sensitivity, we also obtain the covariance matrix and standard deviations for the estimated kinetic parameters. Our proposed approach is demonstrated on 7 case studies that include simulated data as well as actual experimental data. Moreover, our numerical results compare well with the multivariate curve resolution alternating least squares approach. [ABSTRACT FROM AUTHOR]

A novel waterborne polyurethane-silanized CoFe2O-acrylate magnetic pressure-sensitive adhesive was prepared. With the increase of PU content, gel content, swelling capability, and SAFT increased, and fracture energy increased first, then decreased. The T-peeling strength increased from 8.93 to 19.07 N · m−1, tack force increased from No.3 to No.10, while shear resistance increased from 35 to 72 h, and then they decreased. Two empirical models: WA = 90.46 + 125.04[PU]-319.96[PU]2and T = 9.09 + 96.07[PU]-235.11[PU]2, were obtained. With the increase of CoFe2O4content, the saturation magnetization increased from 5.5 to 14.2 emu · g−1, and remanence increased from 1.7 to 3.7 emu · g−1, while coercivity decreased from 875 to 763 Oe. [ABSTRACT FROM PUBLISHER]

New Schiff bases derived from chiral d -camphor were determined to be effective phosphine ligands for the asymmetric palladium-catalyzed allylic alkylation of activated methylene compounds, the allylic etherification of alcohols, and the allylic amination of primary amines or secondary amines, in which the corresponding products with various functional groups were achieved in good yields with excellent enantioselectivities (up to >99 % ee). Remarkably, the palladium catalyst derived from Schiff base L2 afforded the highest level of enantioselectivity reported to date for allylic substitution reactions, including allylic etherification and allylic amination, which revealed the privileged role of d-camphor-derived Schiff bases in palladium-catalyzed allylic substitution reactions. [ABSTRACT FROM AUTHOR]

This paper presents a unified trajectory optimization framework for lunar ascent. Compared with prevailing and emerging studies on lunar ascent trajectory optimization with simplified lunar ascent process and simple constraints, our method formulates in detail the lunar ascent process with complex constraints in a unified manner. The kinematics and dynamics model of lunar ascent with mission-specific constraints explicitly expressed through equalities or inequalities form the fuel-optimal lunar ascent trajectory optimization problem. A proper direct trajectory optimization method is chosen to transcribe the original trajectory optimization problem into a nonlinear programming (NLP) problem solved by a highly efficient NLP solver. The homotopy-based backtracking initial value strategy is designed to enhance convergence of the solving process. First, a two-phase trajectory optimization problem including vertical-rise phase and orbit-insertion phase is solved in the proposed unified framework. Subsequently, to obtain terrain clearance, we directly incorporate terrain description into the lunar ascent problem to obtain the optimal lunar ascent trajectory. Simulation results indicate that the proposed unified trajectory optimization framework has enough adaptability to efficiently handle complex lunar ascent scenarios. The proposed framework may benefit future autonomous lunar ascent missions. [ABSTRACT FROM AUTHOR]

Energy-adaptive color selection or design has recently received much attention with the spreading of the organic light emitting diode (OLED) display. Current solutions optimize color sets by analyzing the energy consumption of the 2D rendered images with the screen-space energy model. The comprehensive influence with respect to the volume visualization like the illumination model, the light, as well as the semi-transparency is not considered. This paper presents an energy-saving color scheme selection and optimization approach for direct volume rendering on OLED displays. We propose an illumination-aware energy estimating model that formulates a simplified equation between the display energy consumption and a specific color scheme in object space, making it practical to achieve global color scheme optimization. By performing the color scheme optimization, we obtain an optimal color transfer function, with which we can generate energy-aware direct volume rendering images for OLED display. Experimental results demonstrate the efficiency of our approach on OLED display systems. [ABSTRACT FROM AUTHOR]

BACKGROUND Ochratoxin A ( OTA), a widely distributed mycotoxin produced by certain species of Aspergillus and Penicillium, has been identified as a carcinogenic, hepatotoxic, teratogenic, nephrotoxic and immunotoxic toxin. To reduce the risk of OTA contamination, a rapid, inexpensive, suitable and on-site assay for its detection is required. RESULTS In this study a dot immunogold filtration assay ( DIGFA) of OTA on high-flow nitrocellulose membrane was developed. Firstly colloidal gold was synthesized and colloidal gold-polyclonal antibody ( PcAb) conjugates against OTA were prepared at the optimal colloidal gold-labeled pH value and package amount. Then the colloidal gold- PcAb conjugates were used to develop the OTA DIGFA. The results demonstrated a visual detection limit of approximately 10 ng mL−1 OTA. In addition, this method had no cross-reaction with zearalenone, aflatoxin B1 or citrinin. CONCLUSION These results indicated that the developed DIGFA could be applied for the actual detection of samples without complicated steps. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Background: A high concentration of CO2 will stagnate the development of the newly formed primordia of Hypsizygus marmoreus, hinder the development of the mushroom cap, thereby inhibiting the normal differentiation of the fruiting body. Moreover, in the previous experiment, our research group obtained the mutant strain HY68 of H. marmoreus, which can maintain normal fruiting under the condition of high concentration of CO2. Our study aimed to evaluate the CO2 tolerance ability of the mutant strain HY68, in comparison with the starting strain HY61 and the control strain HY62. We analyzed the mycelial growth of these strains under various conditions, including different temperatures, pH levels, carbon sources, and nitrogen sources, and measured the activity of the cellulose enzyme. Additionally, we identified and predicted β-glucosidase-related genes in HY68 and analyzed their gene and protein structures. Results: Our results indicate that HY68 showed superior CO2 tolerance compared to the other strains tested, with an optimal growth temperature of 25 °C and pH of 7, and maltose and beef paste as the ideal carbon and nitrogen sources, respectively. Enzyme activity assays revealed a positive correlation between β-glucosidase activity and CO2 tolerance, with Gene14147 identified as the most closely related gene to this activity. Inbred strains of HY68 showed trait segregation for CO2 tolerance. Conclusions: Both HY68 and its self-bred offspring could tolerate CO2 stress. The fruiting period of the strains resistant to CO2 stress was shorter than that of the strains not tolerant to CO2 stress. The activity of β-GC and the ability to tolerate CO2 were more closely related to the growth efficiency of fruiting bodies. This study lays the foundation for understanding how CO2 regulates the growth of edible fungi, which is conducive to the innovation of edible fungus breeding methods. The application of the new strain HY68 is beneficial to the research of energy-saving production in factory cultivation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A sensitive and specific ECL biosensor for Listeria monocytogenes was fabricated. • A zinc oxide-three-dimensional nitrogen-doped graphene composite was prepared. • The 3D porous structure provided a large surface area and loading capacity. • It reliably and effectively detects the content of Listeria monocytogenes in food. A novel electrochemical luminescence (ECL) sensor was fabricated by self-assembly of an amino-modified aptamer onto a zinc oxide-three-dimensional nitrogen-doped graphene composite (ZnO-3DNGH)-modified electrode surface for the measurement of Listeria monocytogenes (LM) levels. As introduced the nitrogen element into the graphene framework, the prepared 3DNGH porous nanomaterial provides better conductivity and a larger surface area for Ru(bpy) 3 2+. Meanwhile, ZnO served as the catalyst, which can effectively enhance the electrochemical performance. In optimal condition, the sensor exhibited a linear relationship between the luminescence signal (△I ECL) and the logarithm of LM concentration (C LM) over the range 15 CFU·mL−1 to 1.5 × 107 CFU·mL−1 with a correlation coefficient of 0.9904 and a limit of detection (S/N = 3) of 5 CFU·mL−1. The sensor was successfully demonstrated to be capable of measuring the level of LM in both pork and milk samples, with rates of recovery of 91.4%-104.2% as calculated by a standard addition method. The results of the study demonstrate that the novel sensor offers a new method of sensitive and selective measurement of LM in complex samples, with considerable potential for applications in the fields of food inspection, molecular diagnosis, and biotechnology. [ABSTRACT FROM AUTHOR]

Nuclear grade Z3CN20.09M cast duplex stainless steel exhibits enhanced cyclic stress response and prolonged low cycle fatigue life at room temperature after thermal aging at 400 °C for up to 6000 h. The threshold strain amplitude for the onset of secondary hardening is shifted to a lower value after thermal aging. Microstructural observations reveal that fatigue cracks tend to initiate from phase boundaries in virgin specimens, but to initiate in the ferrite phase in aged ones. Denser fatigue striations are found on the fracture surface of fatigued specimen subjected to longer thermal aging duration. These observations are explained in the context of thermal aging induced embrittlement of the ferrite phase and deformation induced martensitic phase transformation in the austenite phase. [ABSTRACT FROM AUTHOR]

A model problem arising from optical design of photonic bandgap structure is investigated. That is, the optimization problem is to find the material inhomogeneity in a domain so that a particular eigenmode governed by the scalar Helmholtz equation is localized. The continuum sensitivity analysis of the objective function including the eigenmode is carried out. The derivative of the objective function with respect to the density function is obtained by the sensitivity problem and the adjoint problem in continuum systems. When the multiplicity of eigenmode happens, our strategy is to select the closest eigenmode to the current eigenmode. Four numerical examples in a square domain are studied, with different weight functions and initial density distributions. The numerical results illustrate the validity of the algorithm based on the continuum sensitivity analysis. [ABSTRACT FROM AUTHOR]

The issue of high dust concentration and the difficulty of head-on collection were investigated in this study. The theory of gas-solid two-phase flow was used to conduct numerical simulations on the air flow and dust concentration of the inside intake and the outside pressing particle collector using the FLUENT 6.3.26 software. The best optimization scheme was obtained by analyzing the simulation results of the air flow and dust concentration. Results indicated that when the diameter of the external cavity was 700 or 900 mm, the working surface of the working environment was not effectively improved. In comparison, when the diameter of the external cavity was optimized to 800 mm, most of the dust was trapped in the working face, and the working environment was significantly improved. [ABSTRACT FROM AUTHOR]

Controlling the conformation polysilane through proton-metal exchange reaction of polymethyltolylsilane with alkyllithium using catalytic amount of chiral amines as the chiral origin has been realized. The produced polymers whose chiral origins are (−)-sparteine, ( S , S )-3 or ( S )-2 adopt the P conformation, and whose chiral origins are ( R , R )-3 or ( R )-2 adopt the M conformation. Under the external stimuli of ( S , S )-3 and ( R , R )-3, or ( S )-2 and ( R )-2, the prepared polymers, PS-11 and PS-12 or PS-3 and PS-2 assumed to induced CD spectra were virtual mirror images of each other. These results indicate that the chiral amines can not only induce the helicity of polysilanes, but control the direction of the helix. [ABSTRACT FROM AUTHOR]

The staphylococcal enterotoxins (SEs) are potent gastrointestinal exotoxins synthesized by Staphylococcus aureus, which is responsible for various diseases including septicemia, food poisoning, and toxic shock syndrome, as well as bovine mastitis. Among them, staphylococcal enterotoxin A (SEA) is one of the most commonly present serotypes in staphylococcal food poisoning cases. In this study, the stable hybridoma 3C12 producing anti-SEA monoclonal antibody was established with an equilibrium dissociation constant ( KD) of 1.48 × 10−8 mol·L−1, its ScFv-coding genes were obtained and then the anti-SEA single chain variable fragment (ScFv) protein was expressed in Escherichia coli. Characterization of the expressed target ScFv protein was analyzed by sodium dodecyl sulfate - polyacrylamide gel electrophoresis, Western blot, and enzyme-linked immunosorbent assay. The results demonstrated that the recombinant anti-SEA ScFv protein retained a specific binding activity for SEA, and the KD value of the soluble ScFv was about 3.75 × 10−7 mol·L−1. The overall yield of bioactive anti-SEA ScFv in E. coli flask culture was more than 10 mg·L−1. [ABSTRACT FROM AUTHOR]

Carbonaceous materials such as activated carbon (AC) are effective adsorbents for a number of organic contaminants, and are often used in soil and sediment remediation to sequester organic contaminants. However, little is known about the abiotic reactivity (and thus, the long-term fate) of the carbonaceous material-bound contaminants. We studied the base-promoted dehydrochlorination kinetics of low-level (~1.25mg/g) 1,1,2,2-tetrachloroethane (TeCA) adsorbed to 17 different ACs varying in origin and physicochemical properties. Activated carbon-bound TeCA exhibited significant reactivity--at a given pH the apparent reaction kinetic constants of AC-bound TeCA are 13-70% of the respective kinetic constants of dissolved TeCA. Binding to ACs likely have affected the reactivity of TeCA via two important mechanisms. First, the deprotonated surface O-functional groups (e.g., carboxyl and phenolic groups) catalyzed the base-promoted dehydrochlorination reaction by serving as the conjugate bases. Second, at low contaminant loadings TeCA molecules likely resided primarily in the micropores of ACs (particularly, micropores with diameters of 0.67-1.6nm), wherein mass transfer of OH- (the nucleophile that reacts with TeCA) was inhibited. An important environmental implication is that carbonaceous materials not only sequester contaminants, but also allow contaminants to be slowly degraded in situ. [ABSTRACT FROM AUTHOR]

The efficacy and safety of intra-arterial (IA) chemotherapy versus intravenous (IV) chemotherapy for malignant gliomas were studied. We searched eight electronic databases to identify relevant randomized controlled trials that compared IA chemotherapy with IV chemotherapy in patients with malignant gliomas. This study was conducted in compliance with the Quality of Reporting of Meta-analysis (QUORUM) guidelines. The quality of data was assessed using the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach. Four eligible randomized controlled trials including 460 patients were retrieved. Comparing IA chemotherapy and IV chemotherapy for malignant gliomas, disease control rate, efficacy rate, 1-year, 2-year, and 3-year overall survival as well as grade 3/4 leukocytopenia, thrombocytopenia, and anemia were not statistically different. In conclusion, IA chemotherapy is not superior to IV chemotherapy in terms of efficacy and overall survival as a treatment for malignant gliomas. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Reduction of acyl chlorides with dysprosium metal has been studied. The reducing ability of dysprosium metal is solvent-dependent. Dysprosium metal, which requires neither any additive nor pretreatment, can promote the cross-coupling of acyl chlorides in DMF or DEF to give amides in good yields. When the reaction was performed in N,N-dimethylacetamide, the reductive self-coupling reaction of aroyl chloride took place smoothly and afforded the diaryl-substituted acetylenes in moderate to good yield. [ABSTRACT FROM AUTHOR]

• New method proposed for parameter estimation of ill-conditioned nonlinear systems • Approach is based on transformed parameters from SVD • reduced Hessian and moment criterion are applied to determine transformed parameter subsets • values of inestimable parameters are determined through Monte Carlo Sampling • demonstrated on two nonlinear dynamic systems with improved accuracy and reduced computational cost Parameter estimation is a crucial step in system modeling. In practice, the fundamental models developed by chemical engineers are often complex. There may be parameters that have no or little effect on the model prediction. Also, some parameters may have an impact on model prediction related to other parameters. In this case, it is difficult to estimate all the parameters. The general approach to address this issue is to select a subset of parameters to estimate, and fix the rest at the initial value. Here, a reduced Hessian and statistical criterion-based parameter estimation approach is proposed for improving model prediction. The proposed method considers the influence of the initial parameter values on model prediction. In the process of selecting the optimal subset of transformed parameters based on the mean square error (MSE) of output, the sensitivity matrix is replaced by the reduced Hessian matrix, which can save computational cost of MSE calculation. After obtaining the optimal transformed parameter subset, the optimal initial values are selected based on the statistical criterion. The large difference between the model prediction and the actual model output caused by the arbitrary initial values can be avoided. The numerical results show the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Vacuum diffusion bonding (VDB)-prepared 304 austenite stainless steel (SS)/Q235 carbon steel (CS) clad plates were the focus of this study. Specifically, the metallurgically bonded interfaces, which are known to have good mechanical properties, were investigated. The microstructures of the interfaces were extensively investigated using transmission electron microscopy (TEM). The characterization results revealed the existence of annealing twins and lath martensite precipitates at the interface; the high strength and plasticity at the interface were determined to be attributed to these features. In addition, the distribution and Burgers vector of dislocations at the ferrite–austenite interfaces were investigated by using two-beam method of TEM electron diffraction contrast image (EDCI) technology and high-resolution TEM imaging. As a result, the coordination mechanisms at the ferrite–austenite interfaces during the deformation of the SS/CS clad plates were clarified; the observations include: (1) the perfect dislocation with the Burgers vector a 2 ⟨ 111 ⟩ in the ferrite moved across the interface and formed a perfect dislocation with the Burgers vector a 2 ⟨ 110 ⟩ in the austenite; (2) the ferrite lattice was joined to the perfect dislocation with the Burgers vector a 2 ⟨ 110 ⟩ in the austenite; and (3) the ferrite lattice continuously extended across the interface, and was connected to the austenite lattice. According to the results on the Burgers vector of dislocations, two types of dislocation reactions occurred at the ferrite–austenite interfaces during the deformation. Lastly, the transfer matrix of the orientation relationship (OR) between austenite and ferrite was calculated. The results revealed that the OR differed from that of the conventional OR between body-centered cubic and face-centered cubic structures; thus, it can be concluded that the preparation of SS/CS clad plates via VDB technology may lead to the formation of a unique OR between ferrite and austenite. [ABSTRACT FROM AUTHOR]

Abstract: A series of aryl pyrogallol[4]arenes were efficiently synthesized in excellent yields by cyclocondensation of pyrogallol with aromatic aldehydes under microwave irradiation. The structures of aryl pyrogallol[4]arenes were confirmed by characterization of their acylated derivatives. Under microwave irradiation, alkylation reactions of aryl pyrogallol[4]arenes with some alkylating reagents such as n-butyl iodide, benzyl chloride, and ethyl α-chloroacetate were also finished quickly to yield fully O-alkylated products. The 1H NMR spectra and crystal structures showed that the acylated and alkylated aryl pyrogallol[4]arenes existed mainly in rctt (cis–trans–trans) configuration. [Copyright &y& Elsevier]