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In order to construct waterborne epoxy composite coating with enhanced anti-corrosive performance, the development of efficient additives with good compatibility with adhesive resin and good interaction with steel matrix is of significance. Herein, we adapted two heteroatom (N and S) doped carbon quantum dots, namely ACDs and LCDs, as eco-friendly anti-corrosion components to mix with water-based epoxy resin (WP) to prepare the CDs/WP composite coating. Compared with the ACDs/WP composite, the LCDs/WP composite exhibited a better performance because it contained more functional groups such as carboxyl and hydroxyl on the surface of LCDs, which not only made the system denser but also facilitated the multi-anchor coordination and adsorption on carbon steel. Following immersing in a 3.5 wt% NaCl solution for 28 d, the impedance modulus of LCDs/WP surpassed 109 Ω cm2, exhibiting approximately three orders of magnitude higher values compared to pure WP coatings. The inhibition efficiency was improved by 96.9%. The facile synthesis of LCDs coupled with excellent anti-corrosive properties of LCDs/WP composites, provides a new way for developing anti-corrosion coating materials.

Treated dentin matrix (TDM) is an ideal scaffold material containing multiple extracellular matrix factors. The canonical Wnt signaling pathway is necessary for tooth regeneration. Thus, this study investigated whether the TDM can promote the odontogenic differentiation of human dental pulp stem cells (hDPSCs) and determined the potential role of Wnt/β-catenin signaling in this process. Different concentrations of TDM promoted the dental differentiation of the hDPSCs and meanwhile, the expression of GSK3β was decreased. Of note, the expression of the Wnt/β-catenin pathway-related genes changed significantly in the context of TDM induction, as per RNA sequencing (RNA seq) data. In addition, the experiment showed that new dentin was visible in rat mandible cultured with TDM, and the thickness was significantly thicker than that of the control group. In addition, immunohistochemical staining showed lower GSK3β expression in new dentin. Consistently, the GSK3β knockdown hDPSCs performed enhanced odotogenesis compared with the control groups. However, GSK3β overexpressing could decrease odotogenesis of TDM-induced hDPSCs. These results were confirmed in immunodeficient mice and Wistar rats. These suggest that TDM promotes odontogenic differentiation of hDPSCs by directly targeting GSK3β and activating the canonical Wnt/β-catenin signaling pathway and provide a theoretical basis for tooth regeneration engineering.

Nitrogen and phosphorus discharged into water bodies with sewage are the main causes of water eutrophication.Currently,the adsorption method is a cost-effective and efficient denitrification and phosphorus removal technology. In this study, waste polishing powder, manganese dioxide and sepiolite are used as raw materials, and a novel adsorbent of Sep-pp-MnO2 is prepared through co-precipitation and redox methods for simultaneous removal of ammonia nitrogen and recovery of phosphate in water.The physicochemical properties of the adsorbent are characterised, and the adsorption performances and denitrification and phosphorus removal mechanisms are determined. Results showed that,at a temperature of 25°C and pH of 8, the maximum removal of ammonia nitrogen reaches 11.47mg/g, while the adsorption capacity for phosphates is 14.93mg/g. Adsorption mechanisms indicated that the removal mechanism of phosphate is ligand exchange, while the removal mechanism of ammonia nitrogen involves electrostatic attraction and oxidation to nitrogen. Recycling experiments showed that after five desorption cycles, the material could achieve a removal of 4.7mg/g for ammonia nitrogen, an adsorption capacity of 8.25mg/g for phosphate and a phosphate recovery rate of 55% after desorption with 0.1M NaOH solution. Municipal wastewater validation experiments demonstrated that when the dosage of Sep-pp-MnO2 was 4g/L,Treated water met the Class B requirements of the comprehensive emission standard for pollutants from urban sewage treatment plants in China (GB18918-2002). This study explores a new method for efficient simultaneous nitrogen and phosphorus removal in water and provides a feasible idea for alleviating the shortage of phosphate rock resources.

Perovskite polycrystalline films contain numerous intrinsic and interfacial defects ascribed to the solution preparation process, which are harmful to both the photovoltaic performance and the stability of perovskite solar cells (PVSCs). Although various passivators have been proved to be promising materials for passivating perovskite films, there is still a lack of deeper understanding of the effectiveness of the different passivation methods. Here, the mechanism between antisolvent dripping and additive doping strategies on the passivation effects in PVSCs is systematically investigated with a nonfullerene small molecule (F8IC). Such a passivated effect of F8IC is realized via coordination interactions between the carbonyl (C═O) and nitrile (C–N) groups of F8IC with Pb2+ion of MAPbI3. Interestingly, F8IC antisolvent dripping can effectively passivate the surface defects and thus inhibit the nonradiative charge recombination on the upper part of the perovskite layer, whereas F8IC additive doping significantly reduces the surface and bulk defects and produces a compact perovskite film with denser crystal grains, thus facilitating charge transmission and extraction. Therefore, these benefits are translated into significant improvements in the short-circuit current density (Jsc) to 21.86 mA cm–2and a champion power conversion efficiency of 18.40%. The selection of an optimal passivation strategy should also be considered according to the energy level matching between the passivators and the perovskite. The large energetic disparity is unsuitable for additive doping, whereas it is expected in antisolvent dripping.

A series of CuO catalysts were fabricated through hydrothermal process, thermal decomposition of the precursors of CuC2O4synthesized by soft reactive grinding route and oxalate-gel co-precipitation method, respectively. The discoloration of methylene blue in the presence of H2O2was selected as the activity test model reaction. The as-prepared catalysts were characterized by powder X-ray diffraction, scanning electron microscopy, infrared diffuse reflectance spectrum, and N2-adsorption analysis. The CuO obtained from calcination of dry-grinding-derived oxalate precursor has better catalytic performance than those prepared by conventional wet-chemical method. Examination of the structural characterization shows that the small particle size and relatively high surface area are the main reasons for its excellent activity. Moreover, the pseudo-first-order kinetics model was also employed to understand the discoloration behavior of grinding-derived CuO and the activation energy was calculated to be 56.5 kJ mol−1. The current preparation mechanism of solid-state synthetic technique was also proposed by tracking the precursor structure.

In this work, a novel molecularly imprinted electrochemical sensor of dopamine (DA) has been fabricated with multi-walled carbon nanotubes spaced graphene aerogels (MWCNT/GAs) as the sensing substrate and polypyrrole (PPy) as the molecularly imprinted polymer (MIP). Morphological characterization showed that the MWCNTs were well dispersed on the graphene walls of the aerogels and the spaced GAs exhibited an outstanding loose structure and large effective surface area. Moreover, the introduction of conductive MWCNTs greatly increased the electrical conductivity and electrochemical performance of the composite aerogel. Benefiting from these features, the MWCNT/GAs showed significantly enhanced electrocatalytic activity for DA. Additionally, the MIPs as recognition elements were used for the selective detection of DA. The effects of various experimental parameters, including the volume ratio of the amount of functional monomer to that of template molecules, number of electropolymerization cycles, incubation time and pH of supporting electrolyte were tested and optimized. Under the best conditions, the MIP/MWCNT/GAs electrode could detect DA at concentrations down to 1.67 nM (S/N = 3) with a wide linear range from 5 nM to 20.0 μM. Moreover, the sensor exhibited specific selectivity and good stability. The developed sensor was successfully used for detecting DA in serum, suggesting that the as-prepared sensor could be used for determining the concentration of DA in complex real samples.

Transition-metal carbides (MXenes) are an emerging class of two-dimensional (2D) materials with promising electrochemical sensing performance due to their unique structural and electronic properties. To further improve its sensing performance, herein, the composite of Ti3C2Tx (MXene) and electrochemically reduced graphene oxide (MXene/ERGO) was proposed as electrode material for electrochemical detection of pesticide carbendazim (CBZ). The MXene/ERGO was synthesized by a facile and green electrochemical approach, where the mixture of MXene and graphene oxide (GO) was firstly dropped on the electrode surface, followed by electrochemical reduction of GO. The ERGO conductive networks tightly linked the separated layers of Ti3C2Tx and connected the separated Ti3C2Tx particles, which leading to enhanced electronic conductivity, improved the electrochemical reactivity of electrode materials and facilitated electron transfer between electrode and detection molecules. Consequently, the sensor based on MXene/ERGO exhibited a high sensitive detection of CBZ with a wide linear range of 2.0 nM [?] 10.0 uM and a low limit of detection (LOD) of 0.67 nM. Moreover, the sensor showed good selectivity and reproducibility toward CBZ detection. The proposed sensor was successfully subjected to detect CBZ in cucumber and orange juice samples with acceptable results.

Ultraviolet (UV), as the most common environmental stress factor to human skin, causes redox imbalance and leads to photoaging and the development of cancer. In this work, we screened a nonapeptide (PWH) with good activities of antioxidant, promoting the secretion of type 1 collagen (COL-1) and repairing damaged skin from a series of rationally designed novel short peptides. PWH could alleviate UV-A-induced oxidative stress, restrain pro-inflammatory cytokine production, protect mitochondrial function, and maintain autophagy activity. We also first indicated that inhibiting the PI3K/AKT/mTOR signaling pathway and restoration of autophagy activity might delay the photoaging process in skin cells. Topical applications of PWH were further demonstrated to exhibit significant protection in full-wavelength UV-induced skin aging in mice models both in the prophylaxis and treatment way. In addition, given the good stability and without unwanted toxicity and anaphylaxis, PWH could be a promising candidate for cosmetics and pharmaceuticals.

It is still a huge challenge for bone regenerative biomaterial to balance its mechanical, biological and biodegradable properties. In the present study, a new composite material including treated dentin matrix (TDM) and α-calcium sulphate hemihydrate (α-CSH) was prepared. The optimal composition ratio between TDM and α-CSH was explored. The results indicate that both components were physically mixed and structurally stable. Its compressive strength reaches up to 5.027 ± 0.035 MPa for 50%TDM/α-CSH group, similar to human cancellous bone tissues. Biological experiments results show that TDM/α-CSH composite exhibits excellent biocompatibility and the expression of osteogenic related genes and proteins (ALP, RUNX2, OPN) is significantly increased. In vivoexperiments suggest that the addition of TDM for each group (10%, 30%, 50%) effectively promotes cell proliferation and osteomalacia. In addition, 50% of the TDM/α-CSH combination displays optimal osteoconductivity. The novel TDM/α-CSH composite is a good candidate for certain applications in bone tissue engineering.

A metagenomic library recombinant clone CAPL3, an Escherichia colistrain generated by transformed with metagenomic library from deep-sea sediments, can efficiently produce cold active lipase. The effects of both temperature and dissolved oxygen (DO) on cold active lipase production by batch culture of metagenomic library recombinant clone (CAPL3) from deep-sea sediment were investigated. First, a two-stage temperature control strategy was developed, in which the temperature was kept at 34°C for the first 15h, and then switched to 30°C. The cold active lipase activity and productivity reached 315.2U·ml−1and 8.08U·ml−1·h−1, respectively, increased by both 14.5% compared to the results obtained with temperature controlled at 30°C. In addition, different DO control modes were conducted, based on the data obtained from the different DO control strategies and analysis of kinetics parameters at different DO levels. A step-wise temperature and DO control strategy were developed to improve lipase production, i.e., temperature and DO level were controlled at 34°C, 30% during 0–15h; 30°C, 30% during 15–18h, and 30°C, 20% during 18–39h. With this strategy, the maximum lipase activity reached 354.6U·ml−1at 39h, which was 28.8% higher than that achieved without temperature and DO control (275.3U·ml−1).

Abstract: The components and their concentration ratio of surfactant mixture in aqueous solution of gelatin and sodium carboxymethylcellulose (NaCMC) are very important during the preparation of stable microcapsules for electrophoretic display. In this work, hydrocarbon/fluorocarbon composite surfactant was introduced for the first time into the capsule wall to improve the chemical resistance and barrier property of the microcapsules. By investigating surface tension and zeta potential of NaCMC with the mixture of sodium dodecyl sulfate (SDS)/perfluoro-nonene oxy benzene sulfonate (OBS), we found that both the presence of hydrophobic interaction and the hydrogen bonding between NaCMC and SDS/OBS enhanced the adsorption of NaCMC at the oil/water interface and thus facilitated the formation of capsule wall. The morphology, particle size, surface free energy and thermal stability of the obtained microcapsules were characterized. The results showed that optically transparent microcapsules with uniform size, smooth surface and compact wall can be obtained by adjusting the pH value of the reaction system and the concentration ratio of SDS/OBS. Based on the prepared microcapsules, a matrix display prototype operated at 9 V direct current in static driven mode was fabricated.

We apply genetic screens to delineate modulators of KRAS mutant pancreatic ductal adenocarcinoma (PDAC) sensitivity to ERK inhibitor treatment, and we identify components of the ATR-CHK1 DNA damage repair (DDR) pathway. Pharmacologic inhibition of CHK1 alone causes apoptotic growth suppression of both PDAC cell lines and organoids, which correlates with loss of MYC expression. CHK1 inhibition also activates ERK and AMPK and increases autophagy, providing a mechanistic basis for increased efficacy of concurrent CHK1 and ERK inhibition and/or autophagy inhibition with chloroquine. To assess how CHK1 inhibition-induced ERK activation promotes PDAC survival, we perform a CRISPR-Cas9 loss-of-function screen targeting direct/indirect ERK substrates and identify RIF1. A key component of non-homologous end joining repair, RIF1 suppression sensitizes PDAC cells to CHK1 inhibition-mediated apoptotic growth suppression. Furthermore, ERK inhibition alone decreases RIF1 expression and phenocopies RIF1 depletion. We conclude that concurrent DDR suppression enhances the efficacy of ERK and/or autophagy inhibitors in KRAS mutant PDAC.

AbstractThe purpose of this research was to identify the need for advanced study in kitchen and bath design and business among segments of the kitchen and bath industry. The study also investigated both advanced level competencies impacting the career paths of professional kitchen and bath designers and Web-based distance education to achieve educational goals. A quantitative analysis of a survey of the voting membership of the National Kitchen and Bath Association found a majority demand for advanced study in kitchen and bath design and business by all segments of the industry responding to the survey (498 usable responses). The findings revealed 13 areas of expertise expected of an employee with advanced study and 20 topics of interest to the industry for continuing education and/or master’s degree program. A majority of respondents perceived that continuing education units would be more attractive if they could count toward a master’s degree and that their respective firms would approve of employees pursuing advanced study completed on-line while continuing their present employment. The findings supported the need for advanced study in key areas of kitchen and bath design as well as business management.

The precision and accuracy of diffraction peak positions resolved from the powder X‐ray diffraction spectra of cotton fibers by means of the residuals peak‐fitting procedure of a commercial peak‐fitting software package (PeakFit®) was investigated to explore the potential of such programs in providing reliable data that are not readily apparent in diffuse X‐ray spectra. Each intensity spectrum was fitted by employing a Gaussian function as the peak profile. The precision of 15 pairs of the resolved diffraction peaks is 0.0017 mm; 9 of the 15 pairs fall into the 99% confidence interval. The precision in 2θ of four commonly identified peaks through four independent fittings is from 0.002 to 0.014°. The 2θ accuracy of the resolved peaks is good in comparison to data calculated for both the traditionally accepted and the more recently revised concepts of the cellulose I crystal structure. A peak resolved at about 15.3° may be attributed to the triclinic crystal structure component of cellulose I. Although distinct peaks are not readily apparent in the diffuse spectrum of cellulose, peak‐fitting procedures may provide additional data for structure determination. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2019–2024, 2004

Fourier transform infrared spectra of single fibers of cotton and 18% NaOH treated cotton were obtained before and after fiber pressing to investigate the effect of pressing on the sample. Pressing resulted in improved spectral quality in some regions (e.g., OH stretching) and deteriorated spectral quality in other regions (e.g., CH stretching). Second derivatives of these IR spectra reveal alterations in vibration modes. Thin immature cotton was included in this study to provide a comparison to fibers thinned by pressing. Infrared crystallinity indices, i.e., the ratio of A1370/A2900differ between the pressed and unpressed cotton fibers. Because both quantitative and qualitative changes can result from compression of cotton fibers, caution is required in both selection of the sample preparation method and in interpretation of the infrared spectra.

To identify therapeutic targets for KRASmutant pancreatic cancer, we conduct a druggable genome small interfering RNA (siRNA) screen and determine that suppression of BCAR1sensitizes pancreatic cancer cells to ERK inhibition. Integrative analysis of genome-scale CRISPR-Cas9 screens also identify BCAR1as a top synthetic lethal interactor with mutant KRAS. BCAR1encodes the SRC substrate p130Cas. We determine that SRC-inhibitor-mediated suppression of p130Cas phosphorylation impairs MYCtranscription through a DOCK1-RAC1-β-catenin-dependent mechanism. Additionally, genetic suppression of TUBB3, encoding the βIII-tubulin subunit of microtubules, or pharmacological inhibition of microtubule function decreases levels of MYC protein in a calpain-dependent manner and potently sensitizes pancreatic cancer cells to ERK inhibition. Accordingly, the combination of a dual SRC/tubulin inhibitor with an ERK inhibitor cooperates to reduce MYC protein and synergistically suppress the growth of KRASmutant pancreatic cancer. Thus, we demonstrate that mechanistically diverse combinations with ERK inhibition suppress MYC to impair pancreatic cancer proliferation.

Tin-based perovskite solar cells (PVSCs) are regarded as the most promising alternative among lead-free PVSCs. However, the rapid crystallization for tin-based perovskite tends to cause inferior film morphology and abundant defect states, which make poor photovoltaic performance. Here, 1-butyl-3-methylimidazolium bromide (BMIBr) ionic liquids (ILs) with strong polarity and a low melting point are first employed to produce the Ostwald ripening effect and obtain high-quality tin-based perovskite films with a large grain size. Meanwhile, the non-radiative recombination ascribed from defect states can also be effectively reduced for BMIBr-treated perovskite films. Consequently, a photoelectric conversion efficiency (PCE) of 10.09% for inverted tin-based PVSCs is attained by the Ostwald ripening effect. Moreover, the unencapsulated devices with BMIBr retain near 85% of the original PCE in a N2glovebox beyond 1200 h and about 40% of the original PCE after exposure to air for 48 h.

Transition-metal carbides (MXenes) are an emerging class of two-dimensional (2D) materials with promising electrochemical sensing performance due to their unique structural and electronic properties. To further improve its sensing performance, herein, the composite of Ti3C2Tx(MXene) and electrochemically reduced graphene oxide (MXene/ERGO) was proposed as electrode material for electrochemical detection of pesticide carbendazim (CBZ). The MXene/ERGO was synthesized by a facile and green electrochemical approach, where the mixture of MXene and graphene oxide (GO) was firstly dropped on the electrode surface, followed by electrochemical reduction of GO. The ERGO conductive networks tightly linked the separated layers of Ti3C2Txand connected the separated Ti3C2Txparticles, which leading to enhanced electronic conductivity, improved the electrochemical reactivity of electrode materials and facilitated electron transfer between electrode and detection molecules. Consequently, the sensor based on MXene/ERGO exhibited a high sensitive detection of CBZ with a wide linear range of 2.0 nM ∼ 10.0 μM and a low limit of detection (LOD) of 0.67 nM. Moreover, the sensor showed good selectivity and reproducibility toward CBZ detection. The proposed sensor was successfully subjected to detect CBZ in cucumber and orange juice samples with acceptable results.

Performance benchmarking has played an important role in the research and development in relational DBMS, object-relational DBMS, data warehouse systems, etc. We believe that benchmarking data mining algorithms is a long overdue task, and it will play an important role in the research and development of data mining systems as well.Frequent pattern mining forms a core component in mining associations, correlations, sequential patterns, partial periodicity, etc., which are of great potential value in applications. There have been a lot of methods proposed and developed for efficient frequent pattern mining in various kinds of databases, including transaction databases, time-series databases, etc. However, so far there is no serious performance benchmarking study of different frequent pattern mining methods.To facilitate an analytical comparison of different frequent mining methods, we have constructed an open test bed for performance study of a set of recently developed, popularly used methods for mining frequent patterns in transaction databases and mining sequential patterns in sequence databases, with different data characteristics. The testbed consists of the following components.A synthetic data generator, which can generate large sets of synthetic data in various kinds of data distributions. A few large data sets from real world applications will also be provided.A good set of typical frequent pattern mining methods, ranging from classical algorithms to recent studies. The method are grouped into three classes: frequent pattern mining, max-pattern mining, and sequential pattern mining. For frequent pattern mining, we will demonstrate Apriori, hashing, partitioning, sampling, TreeProjection, and FP-growth. For maximal pattern mining, we will demonstrate MaxMiner, TreeProjection, and FP-growth-max. For sequential pattern mining, we will demonstrate GSP and FreeSpan.A set of performance curves. These algorithms their running speeds, scalabilities, bottlenecks, and performance on different data distributions, will be compared and demonstrated upon request. Some performance curves from our pre-conference experimental evaluations will also be shown.An open testbed. Our goal is to construct an extensible test bed which integrates the above components and supports an open-ended testing service. Researchers can upload the object codes of their mining algorithms, and run them in the test bed using these data sets. The architecture is shown in Figure 1.This testbed is our first step towards benchmarking data mining algorithms. By doing so, performance of different algorithms can be reported consistently, on the same platform, and in the same environment. After the demo, we plan to make the testbed available on the WWW so that it may, hopefully, benefit further research and development of efficient data mining methods.