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Colorectal cancer (CRC) is a highly prevalent malignancy affecting the digestive system on a global scale. This study aimed to explore the previously unexplored role of CHPF in the progression of CRC. Our results revealed a significant upregulation of CHPF expression in CRC tumour tissues compared to normal tissues, with its levels correlating with tumour malignancy. In vitro experiments using CRC cell lines demonstrated that inhibiting CHPF expression suppressed cell proliferation, colony formation and cell migration, while promoting apoptosis. Conversely, overexpressing CHPF had the opposite effect. Additionally, our xenograft models in mice confirmed the inhibitory impact of CHPF knockdown on CRC progression using various cell models. Mechanistic investigations unveiled that CHPF may enhance VEGFB expression through E2F1‐mediated transcription. Functionally, suppressing VEGFB expression successfully mitigated the oncogenic effects induced by CHPF overexpression. Collectively, these findings suggest that CHPF may act as a tumour promoter in CRC, operating in a VEGFB‐dependent manner and could be a potential target for therapeutic interventions in CRC treatment. [ABSTRACT FROM AUTHOR]

Utilizing the low‐cost catalysts with excellent catalytic activities to replace the expensive ones for H2 evolution still faces great challenges. It is significant to design the new catalysts with the synergistic effect to improve the activities and decrease the cost of the applications. Herein, the novel nanocatalyst of graphene quantum dots loaded bimetallic nanoparticles (Pt‐Co/GQDs) has been synthesized for the H2 evolution from hydrolysis of amine borane (AB) for the first time. The result indicates that the Pt‐Co/GQDs nanocatalyst holds the better catalytic activities than Pt/GQDs, exhibiting the bimetallic synergies in the hydrolysis process. The synthesized catalyst has been characterized by various measurements, such as TEM, XPS, EDS, UV–Vis, and PL spectra. The effect of the catalyst on the hydrolysis of AB is investigated. It is demonstrated that the value of total turnover frequencies (TOFs) can arrive to 520 molH2·molPt−1·min−1 via the catalyst designing, which is very high in comparison with other reported catalysts. This work has developed an effective nanocatalyst with a lower cost which is never reported in the hydrolysis of AB, possessing both great significance and huge potential in the H2 evolution by hydrolysis of the hydrogen storage materials. [ABSTRACT FROM AUTHOR]

This paper proposes a new driving solution which adds a skew detection module under the original architecture of source driver to solve the phase skew caused by TCON or SOC instability in the initial state during panel power on, causing the source driver to lock this phase skew and possibly generate the lock signal, thereby causing the source driver to re‐lock and resulting in abnormal display. It can be proven that this driving solution can effectively solve the problems, while ensuring that the skew of different transmission differential pairs is within ± 0.5UI, to avoid the occurrence of abnormal display. [ABSTRACT FROM AUTHOR]

As a widespread foodborne pathogen, Listeria monocytogenes (LM) can potentially cause a large number of food safety incidents, and the mortality rate of humans infected with this pathogen is relatively high. Thus, establishment of a fast and simple inspection technology is imperative. Herein, a solid‐state electrochemiluminescence (ECL) biosensing switch system based on special ferrocene‐labeled molecular beacon aptamer (Fc‐MBA) has been developed for rapid detection of LM. The biosensor consisted of two main parts, an ECL substrate and an ECL intensity switch. ECL substrate was generated by modifying the complex of gold nanoparticle (AuNPs) and ruthenium (II) tris‐(bipyridine) onto Au electrode, and an MBA labeled by Fc that acted as an ECL intensity switch. Moreover, in the presence of LM, the stem‐loop structure of MBA could be opened and the ferrocene was kept away from ECL substrate, which was due to an obvious ECL intensity increment. The limit of detection was 5 CFU/mL, and satisfactory recoveries of 98.1–103.6% were observed. Thus, we propose a novel method for accurate and specific detection of LM. [ABSTRACT FROM AUTHOR]

Halide solid‐state batteries (SSBs) show unparalleled application potential because of their outstanding advantages, such as high ionic conductivity and good compatibility with cathodes. However, operating halide SSBs under freezing temperatures faces big challenges, and the underlying degradation mechanisms are unclear. Herein, the impact of electronic conductivity in low‐temperature halide SSBs is investigated by designing different additives in the composite cathode. It is shown that the electrochemical stability of a halide electrolyte (Li3InCl6) with additives is significantly affected by the degree of electronic conductivity as well as the ambient operational temperature. When the ambient temperatures are below freezing point, the moderate electronic conductivity in the composite cathode is beneficial toward improving the charge transfer kinetics without inducing the decomposition of Li3InCl6. The electrode materials (LiCoO2 cathode and Li3InCl6 electrolytes) show excellent structural and interfacial stability during electrochemical reactions, resulting in a competitive performance at low temperatures. Stable long‐term cycling performance with a capacity retention of 89.2% after 300 cycles is achieved along with a C‐rate capacity of 77.6 mAh g–1 (0.6 C) at −10 °C. This in‐depth study investigates the role of electronic conductivity, which opens the door to future research on low‐temperature SSBs. [ABSTRACT FROM AUTHOR]

Reclamation has been widely accepted as a means to restore abandoned lands. Most studies focused on the improvement of land reclamation explore soil nutrients and microbial activities. However, the effects of time since reclamation on bacterial communities of abandoned salt pans are still unclear. The object of our study are is to: (i) assess the successional change of soil physicochemical properties and bacterial communities in abandoned salt pans with different reclamation histories; and (ii) determine the main limiting factors on the improvement of soil quality in abandoned salt pans. The soils in farmland [reclamation time for blank (RTBL)] and six abandoned salt pans with 1 year (RT1), 2 years (RT2), 3 years (RT3), 4 years (RT4), 8 years (RT8), and 9 years (RT9) since reclamation were sampled to investigate the temporal variation of soil properties, heavy metal content, bacterial community composition, and diversity. Results showed that the soil bulk density (BD), total dissolved salt and median particle size (MMAD) decreased with the increase of time since reclamation, while soil nutrients (soil organic matter, total nitrogen, available phosphorus, available potassium) showed an opposite trend. The bacterial α‐diversity increased first, then decreased. Land reclamation enhanced the relative abundances of Acidobacteria, Chloroflexi, and Actinobacteria but reduced the relative abundances of Proteobacteria, Gemmatimonadetes, and Bacteroidetes. Compared with RTBL, the soil nutrients and bacterial community structure in RT1, RT2, RT3, and RT4 showed a significant difference. After 8‐9 years (RT8 and RT9) of reclamation, the soil nutrients and bacterial community structure in reclaimed abandoned salt pans showed RTBL. Therefore, time since reclamation is a vital driving force for restoring soil physicochemical properties and bacterial communities in abandoned salt pans. [ABSTRACT FROM AUTHOR]

It is well established that experiences make people happy, but we still know little about how individual differences affect the relationship between consumption of experiences and happiness. This study focuses on gender as the predictor of happiness and addresses the following question: Do women and men differ in the way they attain happiness from consumption of experiences? Considering that research shows that women and men differ in how they process information, it is possible that they differ in how much they reflect on an experience too. Therefore, this study also investigates how the relationship between consumption of experiences and gender is moderated by Need for Cognition (NFC) in affecting subjective happiness. The results of a survey of adult consumers show than women derive more happiness and life satisfaction from meaningful experiences than men whereas men derive more happiness and satisfaction with life from pleasurable experiences than women. NFC moderates these results. The study provides evidence for the distinction between pleasure and meaning in consumption contexts and for the important role of gender in consumption of experiences. Its results imply that design and structuring of commercial experiences should take customer gender into account. [ABSTRACT FROM AUTHOR]

Alloying is a well‐accepted strategy for modulating the electronic structures of catalyst materials. Compared to disordered solid‐solution alloys, intermetallic compounds feature ordered atomic arrangements and provide a unique platform with a rich and diverse resource to study the relationships among chemical composition, atomic structure, electronic structure, and properties. Unfortunately, it is still challenging to synthesize the nanostructures of intermetallic compounds for catalysis research. In this study, a series of intermetallic silicides (PtSi, RhSi, Ru2Si3, IrSi), germanide (Ru2Ge3), and stannides (Ru3Sn7, IrSn2, PdSn3, PdSn2) are rationally designed and constructed through a facile molten‐salt‐assisted route. As an example, the PtSi not only shows highly desirable electrocatalytic properties for the hydrogen evolution reaction (HER) with low overpotentials of 22, 38, and 66 mV at a current density of 10 mA cm‐2 in acidic, alkaline, and neutral media, respectively, but exhibits superior durability, as well as >97% faradic efficiency. The theoretical calculations suggest that the introduction of Si to Pt could weaken the binding energy between Pt and H atoms, which further facilitates the hydrogen generation during the HER process. Further, the findings inspired the authors to develop other kinds of metal‐based carbon‐group intermetallic phases with excellent activity in the HER and beyond. [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]

This study advances theoretical insights into blockchain adoption in the context of global value chains from a transaction cost theory perspective. The research has adopted an exploratory qualitative approach using the Netnography method to scrutinize the case of TradeLens—a thriving blockchain‐enabled ecosystem that Maersk and IBM jointly developed. This study applies textual and audiovisual data from company websites and social media. Our findings indicate blockchain technology's salient and strategic relevance in streamlining business processes, improving efficiency, enhancing visibility, transparency, and traceability for value creation in the global value chains. This investigation supports the notion that blockchain, as a disruptor, will transform global trade with the digital tools to share real‐time information and collaborate security to reduce search and information cost, policing and enforcement cost in global economic transactions and administrative friction in trade. In contrast, the bargaining cost will increase if the information for the transaction is hard to verify where human actor intervention will be required, implying relatively higher designing costs in codifying the agreements in smart contracts. [ABSTRACT FROM AUTHOR]

Objective: The topical antispasmodic agent l‐menthol is commonly used for gastric peristalsis suppression during diagnostic upper gastrointestinal (GI) endoscopy. We evaluated the efficacy and safety of a single dose l‐menthol solution in suppressing gastric peristalsis during upper GI endoscopy in Chinese patients. Methods: In this phase III, multicenter, randomized, double‐blind, placebo‐controlled study (ClinicalTrials.gov: NCT03263910), 220 patients scheduled to undergo upper GI endoscopy at five Chinese referral centers received a single dose of either 160 mg of l‐menthol (n = 109) or placebo (n = 111). Both treatments were sprayed endoscopically on the gastric mucosa. An independent committee evaluated the degree of gastric peristalsis (peristaltic score: grade 1–5). Results: At baseline, the proportion of patients with grade 1 peristalsis (no peristalsis) did not differ between the groups. The proportion of patients with grade 1 peristalsis post‐treatment was significantly higher in the l‐menthol group (40.37%, 44/109) versus the placebo group (16.22%, 18/111; P < 0.001); the difference between the groups was 24.15% (95% confidence interval: 12.67%–35.63%; P < 0.001). In the l‐menthol group, 61.47% of patients had grade 1 peristalsis after endoscopy versus 24.55% in the placebo group (P < 0.001). The ease of intragastric examination correlated significantly with the grade of peristalsis. The incidence of adverse events was comparable between the groups (P = 0.340). Conclusions: During upper GI endoscopy, a single dose of l‐menthol solution (160 mg) sprayed on the gastric mucosa significantly attenuated gastric peristalsis versus placebo, thereby improving the visual stability without any safety concerns. [ABSTRACT FROM AUTHOR]

(A) The serum RelB and HE4 levels in the CKD patients with different stages (CKD I and II, n = 25; CKD III and IV, n = 7) and the normal controls (control, n = 60). Our data revealed that RelB can not only discriminate CKD patients from normal subjects but also can distinguish CKD patients at different stages. GLO:F2H7/01may21:ctm2362-fig-0002.jpg PHOTO (COLOR): 2 The expression of RelB is correlated with kidney fibrosis and renal function indexes in CKD patients and can discriminate CKD patients from the healthy control. [Extracted from the article]

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]

A model‐based experimental design strategy is developed to select a minimal set of measured points from a time series of experiments. Based on reduced Hessian information embedded within a mixed integer nonlinear program, an optimal time series is determined that leads to well‐fitted models, with ratios of parameter standard deviation to estimated value within acceptable bounds. Demonstrated on three examples, the proposed approach is effective and efficient especially for time‐consuming and expensive measurements. [ABSTRACT FROM AUTHOR]

Parameter estimation is a critical step in the building of process models. Given the nonlinear structure and limited measurements, it is often difficult to correctly estimate all the parameters involved in the model. Linear dependence and low correlation among the parameters are the main problems to be handled in parameter estimation. The common approach is to estimate a subset of the parameters by fixing the others at reasonable values. However, it is a challenge to determine which parameters can be properly estimated. In this work, the ratio between standard deviation and estimated parameter value is introduced for evaluating the estimability. A Gauss‐Jordan elimination based approach is proposed for parameter estimability ranking. Combined with the proposed ranking approach and approximate ratio criterion, a reduced Hessian based approach is proposed for parameter selection and estimation under a simultaneous collocation framework. The proposed approach is at least as effective and more efficient than competing approaches based on multiple eigenvalue decompositions or orthogonalizations for larger problems. Three case studies with increasing complexity are presented to demonstrate the performance of the proposed approach. [ABSTRACT FROM AUTHOR]

An increasing concentration of lead (Pb) in urban contaminated soil due to anthropogenic activities has been a global issue threatening human health. The use of urban ornamental plants as phytoremediation of Pb‐contaminated soil is a new choice. In the present experiment, the physiological and biochemical response of five ornamental plants to increase in concentrations of C4H6O4Pb·H2O in the soil were measured to investigate these plans' Pb tolerance strategies and abilities. Our results showed that Pb stress significantly inhibited the growth and the biomass of all the plants. The root activity (RA), net photosynthetic rate (Pn), and chlorophyll (Chl) content in Pb‐stressed leaves were significantly decreased, whereas the leaf proline (Pro), soluble sugar (SS), and membrane stability index (MSI) were remarkable increased compared with those in the control group. By application of all‐subsets regression and linear regression, the reduction in photosynthetic capacity in the five plants is mainly due to the decrease in the leaf Chl content caused by Pb stress. The bioconcentration factor (BCF) in Canna generalis was greater than 1, while in the other plants were lower than 1, suggesting that Canna generalis had the highest Pb accumulation ability. The translocation factor (TF) in all the plants were lower than 1, suggesting that Pb preferentially accumulated in the external part of roots. By calculating the comprehensive evaluation value (CEV), Iris germanica L. was found to be the most sensitive species, and Canna generalis was the most tolerant species, to Pb stress among the five ornamental plants. [ABSTRACT FROM AUTHOR]

Biochar is composed of carbonaceous and inorganic (ash) fractions. The structural properties of carbonaceous fractions and the composition of ash in biochar are both variable with pyrolysis temperature. However, it is unknown whether ash may play different roles in sorption of organic compounds to the carbonaceous fraction of biochars produced at different temperatures. Hence, in this study, the pristine biochars produced at 300–900°C and their corresponding deashed biochars were investigated, and the combined roles of carbonaceous fraction and ash in sorption of triclosan were compared. The results showed that the biochars produced at 300–400°C had high content of uncarbonized organic structure with dominating partition effect. The combination of uncarbonized organic structure and ash had comparable or even higher sorption coefficient (KD) for triclosan at low concentration compared with a single uncarbonized organic structure. However, for the biochars produced at 600–900°C, which were mainly composed of carbonized or graphitized carbon structure, ash had significant effect on triclosan sorption by reducing surface adsorption and pore filling effect. The combination of carbonaceous fraction and ash decreased KD values for triclosan at any tested concentrations. In addition, the results of pH effect on sorption indicated that ash possibly decreased the electrostatic repulsion of deprotonated phenolic hydroxyl between biochars and triclosan. Accordingly, it will be more valuable to design biochars for pollutant sorption from the perspective of combined role of carbonaceous fraction and ash rather than a single role of carbonaceous fraction. [ABSTRACT FROM AUTHOR]

Being innovative and adaptive to changing business environment fosters and sustains the success of corporations with heritage. Our article addresses the insights of the innovation strategy of John Lewis Partnership (JLP) as a corporate heritage brand and reveals that strategic innovation the key strand of JLP's brand heritage, which has contributed to the continuous success of JLP for over a century. Developed from the S‐curve innovation theory, we have developed a corporate heritage brand innovation process framework with four stages: invention, sustainability, expansion, and extension. Our research confirms that S‐curve innovation theory can be applied to scrutinize organizational innovation of corporations with heritage brand. [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]

In many studies, kinetic parameter estimation from spectroscopic data is performed with the absorbing species known beforehand, as this provides a straightforward link between the reaction models to the spectroscopic data. In practice, however, the absorbing species are generally unknown and they are only estimated based on professional experience and prior knowledge of the kinetic reaction. In this work, we propose an optimization strategy with both continuous and discrete decision variables in order to estimate kinetic parameters from spectroscopic data with unknown absorbing species. Also included in our approach is an estimability analysis for kinetic parameters based on the Gram‐Schmidt orthogonalization procedure, along with covariance estimation. Four case studies were considered, which demonstrate the effectiveness of our approach. The first and second have simulated data and illustrate our approach with known solutions. The third and fourth are based on actual experiments from spectroscopy data sets. © 2018 American Institute of Chemical Engineers AIChE J, 64: 3595–3613, 2018 [ABSTRACT FROM AUTHOR]

BACKGROUND Immunoassays are widely employed techniques to detect aflatoxins since they are rapid, selective and sensitive. One common disadvantage of them is using aflatoxins as standard substances, which may trigger exposure risks to operators and environmental contamination without proper handling. Anti-idiotypic antibodies (anti-Ids or Ab2s), also named as internal-image anti-Ids, are able to mimic and function as antigens, so a non-toxic enzyme-linked immunosorbent assay ( ELISA) for aflatoxin B1 ( AFB1) is developed and validated using anti-Ids as substitutes. RESULTS Mouse monoclonal anti-idiotypic antibody ( McAb2) to AFB1 was generated by the hybridoma technique using Fab fragments of rabbit anti- AFB1 idiotype antibody (Ab1) as immunogen. As indicated by indirect competitive ELISA, McAb2, represented an internal-image of antigen AFB1, was able to bind Fab with competition to AFB1. Then, analysis of AFB1 in spiked samples by non-toxic ELISA using anti-Ids as substitutes was developed, and it showed no significant differences with comparison to AFB1 as competitive antigens. CONCLUSION Our work demonstrated that anti-Ids could be used as internal-image mimicry of AFB1, and it had potential applications in immunoassays for antigen substitution to reduce operational risk for operators and environmental contamination. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Singular optimal control problems arise frequently on a broad range of chemical engineering applications. Determination of the accurate dynamic structure of the optimal solution profile and the junctions between optimal nonsingular and singular arcs is essential for operating strategies, as well as equipment designs for many processes. In a previous study ( Chen, Shao, and Biegler, AIChE J. 60(3), pp. 966-979, 2014) a nested optimization formulation that finds the optimal mesh distribution and determines exact control profiles for nonsingular optimal control problems without state constraints is developed. This study extends this approach to singular optimal control problems. To satisfy the necessary optimality conditions for singular optimal control problems with a well-defined solution strategy, the overall nonlinear programming formulation resulting from direct transcription is decomposed into inner and outer problems. The key feature of this algorithm is that it converges to a solution that satisfies the discretized Euler-Lagrange equations of the original singular optimal control problem; we prove this under suitable assumptions. This is obtained through the introduction of pseudomultipliers that reconstruct the necessary optimality conditions for singular optimal control in the outer problem. We demonstrate this approach on eight classical singular control problems with known solutions, as well as three larger singular control problems derived from chemical engineering applications. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3611-3627, 2016 [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]

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]

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]

The first total synthesis of (±)-latifolin has been accomplished in six steps and 47.8% overall yield. To understand the relative importance of phenolic OH and benzhydryl CH hydrogen on the antioxidant activity of latifolin, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and density functional theory (DFT) studies were carried out. On scavenging DPPH radical in ethanol, the activity of latifolin ( 1) bearing phenolic hydrogen is remarkably higher than analogue 10 bearing no phenolic hydrogen. Therefore, Phenolic hydrogen is responsible for latifolin's antioxidant activity rather than benzhydryl CH hydrogen. Furthermore, the 5-OH BDE is lower than 2′-OH and 7-CH BDEs by a DFT calculation, respectively. Based on theoretical results it is definitely concluded that the phenolic 5-OH plays a major role in the antioxidant activity of latifolin. [ABSTRACT FROM AUTHOR]

Optimal control has guided numerous applications in chemical engineering, and exact determination of optimal profiles is essential for operation of separation and reactive processes, and operating strategies and recipe generation for batch processes. Here, a simultaneous collocation formulation based on moving finite elements is developed for the solution of a class of optimal control problems. Novel features of the algorithm include the direct location of breakpoints for control profiles and a termination criterion based on a constant Hamiltonian profile. The algorithm is stabilized and performance is significantly improved by decomposing the overall nonlinear programming (NLP) formulation into an inner problem, which solves a fixed element simultaneous collocation problem, and an outer problem, which adjusts the finite elements based on several error criteria. This bilevel formulation is aided by a NLP solver (the interior point optimizer) for both problems as well as an NLP sensitivity component, which provides derivative information from the inner problem to the outer problem. This approach is demonstrated on 11 dynamic optimization problems drawn from the optimal control and chemical engineering literature. © 2014 American Institute of Chemical Engineers AIChE J, 60: 966-979, 2014 [ABSTRACT FROM AUTHOR]

Singular optimal control plays an important role in process engineering, including optimal operation of batch and semi‐batch reactions. However, for many practical applications, accurate solution of singular optimal control profiles is still an open issue. In particular, numerical optimization must deal with an ill‐conditioned problem that often leads to very slow convergence or failure. Starting from the nested approach in our previous work in 2016, this study develops a more efficient strategy for singular control through a heuristic approach for the outer problem. The approach includes three stages. Starting from a coarse distribution of finite elements, sufficiently many finite elements are inserted where control profiles are steep and fixed gridpoints are inserted on the basis of error estimation of state profiles. Then, moving gridpoints are inserted where the modified switching function is violated. Initial junctions are obtained by moving the latest inserted gridpoints. Moreover, further mesh refinements are considered based on switching point detection and a moving grid point update strategy, until modified switching conditions are satisfied over the whole‐time span. A key feature of this approach is that only a subset of finite elements needs to move during optimization. Complexity of the optimization formulation is considerably decreased compared to our previous work. This approach is demonstrated on eight classical singular control problems with known solutions, as well as six complex singular control problems drawn from the chemical engineering literature. [ABSTRACT FROM AUTHOR]

New Schiff bases are effective chiral phosphine ligands for the asymmetric palladium-catalyzed allylic alkylation of activated methylene compounds, the allylic etherification of alcohols, and the allylic amination with primary or secondary amines. [ABSTRACT FROM AUTHOR]

The reaction of silylene (I) with aromatic nitriles bearing electron-donating substituents on the phenyl ring (II) leads to the desired 1,4-diaza-2-siloles (III), whilst the reaction with aromatic nitriles with strong electron-withdrawing substituents (IV) affords 1,3-diaza-2-siloles (V). [ABSTRACT FROM AUTHOR]