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Saxitoxin (STX), an exceptionally potent marine toxin for which no antidote is currently available, is produced by methanogens and cyanobacteria. This poses a significant threat to both shellfish aquaculture and human health. Consequently, the development of a rapid, highly sensitive STX detection method is of great significance. The objective of this research is to create a novel approach for identifying STX. Therefore, amplified luminescent proximity homogeneous assay (AlphaLISA) was established using a direct competition method based on the principles of fluorescence resonance energy transfer and antigen–antibody specific binding. This method is sensitive, rapid, performed without washing, easy to operate, and can detect 8–128 ng/mL of STX in only 10 min. The limit of detection achieved by this method is as low as 4.29 ng/mL with coefficients of variation for the intra-batch and inter-batch analyses ranging from 2.61% to 3.63% and from 7.67% to 8.30%, respectively. In conclusion, our study successfully establishes a simple yet sensitive, rapid, and accurate AlphaLISA method for the detection of STX which holds great potential in advancing research on marine biotoxins. [ABSTRACT FROM AUTHOR]

Due to the fundamental differences between the quantum world and the classical world, some phenomena, such as entanglement and wave–particle duality, only exist in the quantum realm. These peculiar phenomena cannot be demonstrated by classical means: Quantum networks, quantum cryptography, and quantum precision measurements all require quantum sources. Photons are particularly well-suited as quantum sources owing to their minimal interaction with the environment, high flight speed, and ease of interaction with current typical quantum systems. Single-photon sources include pulsed excitation of quantum dots, spontaneous parametric down-conversion, and photon blockade. Herein, we propose that the anti-Jaynes–Cummings model can induce a pronounced photon antibunching effect when subjected to intense cavity dissipation. Similar to the photon blockade caused by strong photon–photon interaction, this antibunching effect is referred to as 'dissipation-induced blockade'. Our findings indicate that the minimum decay rate of a qubit, coupled with a high decay rate for photons, is conducive to achieving strong antibunching within the system. Notably, g (2) (0) < g (2) (τ) , a characteristic of photon antibunching, is only valid under the optimal condition Δ = 0 . Conversely, g (2) (0) < 1 is satisfied across all parameters, indicating that g (2) (0) < 1 is not a prerequisite for antibunching in the anti-Jaynes–Cummings model. Moreover, under the optimal conditions of the antibunching effect, the average photon number attains its peak value. Consequently, the current anti-Jaynes–Cummings model is promising for developing single-photon sources characterized by excellent purity and average photon number. [ABSTRACT FROM AUTHOR]

Spatial patterns of leaf carbon (C), nitrogen (N), and phosphorus (P) stoichiometry play a pivotal role in the comprehension of terrestrial ecosystem dynamics, nutrient cycling, in responses to contemporary global climate change, and the evolutionary trajectories of leaf morphology and function. These patterns are not only solely shaped by plant and community composition, but also are profoundly influenced by environmental factors. Therefore, there is a compelling need for an in-depth investigation into individual species to discern the intricate impacts of soil and climate on leaf stoichiometry. In this study, we assessed the C, N, and P concentrations of mature leaves from 20 Phyllostachys propinqua populations in the urban forest across northern China covering a substantial latitudinal gradient. Our findings revealed that the average leaf concentrations of C, N, and P in P. propinqua were recorded at 0.46 g g−1, 23.19 mg g−1, and 1.40 mg g−1, respectively. Notably, we observed that leaf C and P concentrations, as well as the C:N ratios, exhibited significant increases with rising latitude. Conversely, leaf N concentrations and N:P ratios exhibited a marked decline with increasing latitude. These patterns were primarily driven by climate factors such as mean annual temperature (MAT) and lowest temperature (LT). In contrast, we found that only leaf C concentrations were correlated with soil N levels. These results underscored the differential spatial distribution of leaf C, N, and P stoichiometry in urban forest across northern China, predominantly instigated by climatic factors, particularly in regions characterized by lower temperatures. Our findings further suggest that P. propinqua enhances its adaptability to low-temperature environments by elevating leaf C and P concentrations. [ABSTRACT FROM AUTHOR]

To reduce the environmental impact of offshore oil and gas, the hydrocarbon discharge regulations tend to become more stringent. One way to reduce the oil discharge is to improve the control systems by introducing new oil-in-water (OiW) sensing technologies and advanced control. De-oiling hydrocyclones are commonly used in offshore facilities for produced water treatment (PWT), but obtaining valid control-oriented models of hydrocyclones has proven challenging. Existing control-oriented models are often based on droplet trajectory analysis. While it has been demonstrated that these models can fit steady-state separation efficiency data, the dynamics of these models have either not been validated experimentally or only describe part of the dynamics. In addition to the inlet OiW concentration, they require the droplet size distribution to be measured, which complicates model validation as well as implementation. This work presents an approach to obtain validated nonlinear models of the discharge concentration, separation efficiency, and discharge rate, which do not require the droplet size distribution to be measured. An exhaustive search approach is used to identify control-oriented polynomial-type Hammerstein–Wiener (HW) models of de-oiling hydrocyclones based on concentration measurements from online OiW monitors. To demonstrate the effectiveness of this modeling approach, a PI controller is designed using the Skogestad internal model control (SIMC) tuning rules to control the discharge OiW concentration directly. The identification experiment emulates an offshore PWT system with installed OiW monitors, which is realistic with the legislative incentive to include online OiW discharge measurements. The proposed approach could enable the application of OiW-based control on existing offshore PWT facilities, resulting in improved de-oiling performance and reduced oil discharge. [ABSTRACT FROM AUTHOR]

Nanocellulose hydrogels are a crucial category of soft biomaterials with versatile applications in tissue engineering, artificial extracellular matrices, and drug-delivery systems. In the present work, a simple and novel method, involving the self-assembly of cellulose nanocrystals (CNCs) induced by tannic acid (TA), was developed to construct a stable hydrogel (SH-CNC/TA) with oriented porous network structures. The gelation process is driven by the H-bonding interaction between the hydroxyl groups of CNCs and the catechol groups of TA, as substantiated by the atoms in molecules topology analysis and FTIR spectra. Interestingly, the assembled hydrogels exhibited a tunable hierarchical porous structure and mechanical moduli by varying the mass ratio of CNCs to TA. Furthermore, these hydrogels also demonstrate rapid self-healing ability due to the dynamic nature of the H-bond. Additionally, the structural stability of the SH-CNC/TA hydrogel could be further enhanced and adjusted by introducing coordination bonding between metal cations and TA. This H-bonding driven self-assembly method may promote the development of smart cellulose hydrogels with unique microstructures and properties for biomedical and other applications. [ABSTRACT FROM AUTHOR]

Okadaic acid (OA), a marine biotoxin produced by microalgae, poses a significant threat to mariculture, seafood safety, and human health. The establishment of a novel, highly sensitive detection method for OA would have significant practical and scientific implications. Therefore, the purpose of this study was to develop an innovative approach for OA detection. A competitive amplified luminescent proximity homogeneous assay (AlphaLISA) was developed using the principle of specific antigen–antibody binding based on the energy transfer between chemiluminescent microspheres. The method was non-washable, sensitive, and rapid, which could detect 2 × 10−2–200 ng/mL of OA within 15 min, and the detection limit was 4.55 × 10−3 ng/mL. The average intra- and inter-assay coefficients of variation were 2.54% and 6.26%, respectively. Detection of the actual sample results exhibited a good correlation with high-performance liquid chromatography. In conclusion, a simple, rapid, sensitive, and accurate AlphaLISA method was established for detecting OA and is expected to significantly contribute to marine biotoxin research. [ABSTRACT FROM AUTHOR]

Submicron droplets are ubiquitous in nature and widely applied in fields such as biomedical diagnosis and therapy, oil recovery and energy conversion, among others. The submicron droplets are kinetically stable, their submicron size endows them with good mobility in highly constricted pathways, and the high surface-to-volume ratio allows effective loading of chemical components at the interface and good heat transfer performance. Conventional generation technology of submicron droplets in bulk involves high energy input, or relies on chemical energy released from the system. Microfluidic methods are widely used to generate highly monodispersed micron-sized or bigger droplets, while downsizing to the order of 100 nm was thought to be challenging because of sophisticated nanofabrication. In this review, we summarize the microfluidic methods that are promising for the generation of submicron droplets, with an emphasize on the device fabrication, operational condition, and resultant droplet size. Microfluidics offer a relatively energy-efficient and versatile tool for the generation of highly monodisperse submicron droplets. [ABSTRACT FROM AUTHOR]

Antibiotic abuse in the conventional treatment of microbial infections, such as inflammatory bowel disease, induces cumulative toxicity and antimicrobial resistance which requires the development of new antibiotics or novel strategies for infection control. Crosslinker-free polysaccharide-lysozyme microspheres were constructed via an electrostatic layer-by-layer self-assembly technique by adjusting the assembly behaviors of carboxymethyl starch (CMS) on lysozyme and subsequently outer cationic chitosan (CS) deposition. The relative enzymatic activity and in vitro release profile of lysozyme under simulated gastric and intestinal fluids were investigated. The highest loading efficiency of the optimized CS/CMS-lysozyme micro-gels reached 84.9% by tailoring CMS/CS content. The mild particle preparation procedure retained relative activity of 107.4% compared with free lysozyme, and successfully enhanced the antibacterial activity against E. coli due to the superposition effect of CS and lysozyme. Additionally, the particle system showed no toxicity to human cells. In vitro digestibility testified that almost 70% was recorded in the simulated intestinal fluid within 6 h. Results demonstrated that the cross-linker-free CS/CMS-lysozyme microspheres could be a promising antibacterial additive for enteric infection treatment due to its highest effective dose (573.08 μg/mL) and fast release at the intestinal tract. [ABSTRACT FROM AUTHOR]

Potato flour (PF) is rich in health-promoting compounds that can improve the nutritional benefits of food products after blending with wheat flour. However, the incorporation of PF may influence the processing characteristics of mixed powders and the quality properties of products. In this study, the physicochemical properties, processing characteristics, and structures of mixed powders and their corresponding doughs with different PF content (0%, 10%, 20%, 30%, 40%, 60%, 80%, and 100%) were investigated. The addition of PF dramatically increased the fiber content from 0.09 to 1.10 g·kg−1 but diluted the protein in wheat flour. The peak and final viscosity of mixed powders decreased (from 5111.00 to 1806.33 cP and 5195.33 to 2135.33 cP, respectively) with an increase in PF fraction. The incorporation of PF significantly increased gelatinization temperature. The rapidly digestible starch decreased from 30.48% to 19.67%, and resistant starch increased from 16.93% to 41.84% when the PF content increased from 0% to 100%. The water absorption, stability time, and development time decreased with an increase in PF levels. The G′ and G″ of the dough decreased as the addition amount of PF increased, while tan δ presented a complex change tendency. Due to the decrease in protein content in the mixed powders, the addition of PF in wheat flour notably decreased the Hm values of doughs and total carbon dioxide volume produced during fermentation. Additionally, the SH and S–S contents decreased with an increase in PF fraction. Scanning electron microscopy results showed that when the PF content reached up to 80%, a poor and discontinuous gluten framework was formed in the dough. Results showed that PF affected the processing characteristics and gluten structures of wheat dough and was related to the interaction or competition for water molecules between protein and starch, as well as potato starch and wheat starch. Thus, the results of the present study can provide insights into the optimal level of addition of PF during the development of potato-based food products. [ABSTRACT FROM AUTHOR]

The high mechanical strength, large specific surface area, favorable biocompatibility, and degradability of nanocellulose (CNC) enable it to be a potential alternative to petroleum-based materials. However, the traditional preparation of CNCs requires a large amount of strong acid, which poses a serious challenge to equipment maintenance, waste liquid recycling, and economics. In this study, a solid and easily recoverable zirconium phosphate (ZrP) was used to assist in the phosphoric acid co-catalyzed hydrolysis of lignocellulose for extracting CNCs. Due to the presence of acidic phosphate groups, ZrP has a strong active center with a high catalytic activity. With the assistance of ZrP, the amount of phosphoric acid used in the reaction is significantly reduced, improving the equipment's durability and economic efficiency. The effects of the process conditions investigated were the phosphate acid concentration, reaction temperature, and reaction time on the yield of CNCs. The Box–Behnken design (BBD) method from the response surface methodology (RSM) was applied to investigate and optimize the preparation conditions. The optimized pre-treatment conditions were 49.27% phosphoric acid concentration, 65.38 °C reaction temperature, and 5 h reaction time with a maximal cellulose yield (48.33%). The obtained CNCs show a granular shape with a length of 40~50 nm and a diameter of 20~30 nm, while its high zeta potential (−24.5 mV) make CNCs present a stable dispersion in aqueous media. Moreover, CNCs have a high crystallinity of 78.70% within the crystal type of cellulose Ⅰ. As such, this study may pioneer the horizon for developing a green method for the efficient preparation of CNC, and it is of great significance for CNCs practical production process. [ABSTRACT FROM AUTHOR]

In this study, we investigated the phonon blockade effect in a parametrically driven and dissipative acoustic cavity at finite temperature. With the approximated analytical results based on the steady-state density-matrix master equation, we found that a quantum-interference-induced phonon blockade exists at finite temperature. We found a crossover between the quantum and thermal regimes on the curve of the second-order correlation function of the acoustic mode as the temperature increases. This phenomenon implies an asymmetry about the quantum and classic regimes. We also numerically simulated the single-phonon emission using the Monte Carlo wave function method. The results showed that a wide and deep dip around the zero time delay exists on the curve of the time-delayed second-order correlation function, which implies the possibility of observing a strong phonon blockade with pulse driving. Our study outlines a potential candidate for a efficient single-phonon source and applications in quantum information and phononic quantum networks. [ABSTRACT FROM AUTHOR]

In temperature sensitive hydrogels, the swelling degree or light transmittance of the gel itself changes with variations in ambient temperature, prompting its wide application in controlled drug release, tissue engineering, and material separation. Considering the amphiphilic structure of β-cyclodextrin (β-CD), a cellulose-based supramolecular hydrogel with superior temperature sensitivity was synthesized based on a combination of cellulose and β-CD as well as the host–guest interaction between β-CD and polypropylene glycol (PPG). In the one-pot tandem reaction process, chemical grafting of β-CD on cellulose and the inclusion complexation of β-CD with PPG were performed simultaneously in a NaOH/urea/water system. The obtained supramolecular hydrogel had a lower critical solution temperature (LCST) of 34 °C. There existed covalent bonding between the cellulose and β-CD, host–guest complexation between the β-CD and PPG, and hydrogen bonding and hydrophobic interactions between the components in the network structure of the supramolecular hydrogel. The combination of various covalent and non-covalent bonds endowed the resulting supramolecular hydrogel with good internal network structure stability and thermal stability, as well as sensitive temperature responsiveness within a certain range—implying its potential as a smart material in the fields of medicine, biology, and textiles. This work is expected to bring new strategies for the fabrication of cellulose-based thermosensitive materials, benefitting the high-value utilization of cellulose. [ABSTRACT FROM AUTHOR]

Based on the self-passivation function of chitosan, an efficient, and green synthesis strategy was applied to prepare chitosan carbon dots (CDs). The quantum yield of carbon dots reached 35% under the conditions of hydrothermal temperature of 200 °C, hydrothermal time of 5 h, and chitosan concentration of 2%. Moreover, the obtained carbon dots had high selectivity and sensitivity to Fe3+. Based on the Schiff base reaction between the aldehyde groups of dialdehyde cellulose nanofibrils (DNF) and the amino groups of CDs, a chemically cross-linked, novel, fluorescent composite film, with high transparency and high strength, was created using one-pot processing. Knowing that the fluorescence effect of the composite film on Fe3+ had a linear relationship in the concentration range of 0–100 μM, a fluorescent probe can be developed for quantitative analysis and detection of Fe3+. Owing to their excellent fluorescent and mechanical properties, the fluorescent nanocomposite films have potential applications in the fields of Fe3+ detection, fluorescent labeling, and biosensing. [ABSTRACT FROM AUTHOR]

The high strength, high specific surface area, excellent biocompatibility, and degradability of nanocellulose (NCC) make it a potential reinforcing phase for composite materials. However, the polyhydroxyl property of NCC renders it prone to self-aggregation and it has weak interfacial compatibility with non-polar substrates, limiting its enhancement performance for composite materials. Therefore, based on the high reactivity of NCC, the chemical modification of NCC to introduce functional groups is the basis for effectively reducing its self-aggregation, improving its interfacial compatibility with the polymer matrix, and creating nanocellulose-based functional materials. The existing functional modifications of NCC have limitations; they require cumbersome steps, generate low yields, and are environmentally unfriendly. Herein, ureido-pyrimidinone (UPy) was introduced to NCC through a sustainable and high-efficiency avenue formed by the mechanochemical synergy of microwaves and ultrasonication. The obtained UPy-modified nanocellulose (NCC-UPy) exhibited a rod-like shape, with a length of 200–300 nm and a width of 20–30 nm, which presented oriented and stable dispersion in an aqueous medium, and the zeta potential reached −40 mV. Moreover, NCC-UPy had good thermostability (>350 °C) and high crystallinity (82.5%) within the crystal type of cellulose I. Using the as-prepared NCC-UPy as a molecular bridge, it was organically combined with epoxy resin through multiple hydrogen bonds to construct a nanocomposite membrane with superior mechanical strength and thermal stability. The results revealed that NCC-UPy dispersed uniformly in the epoxy matrix without aggregating and that the interfacial compatibility was good, leading to an 87% increase in the tensile strength of the formed nanocomposite membrane when 0.5 wt.% NCC-UPy was loaded. It was proved that NCC-UPy had remarkable reinforcing potential and effective stress transfer capacity for composites. Consequently, this study may open the door to the development of a one-pot green approach for undertaking the functional modification of NCC, and it is of great significance for the development of NCC-based nanocomposites. [ABSTRACT FROM AUTHOR]

Fluorescent cellulose nanofibers (FCNFs), with a high yield, were prepared via one-pot hydrolysis and the grafting reaction of cellulose with thiazolipyridine carboxylic acid (TPCA). The hydrolysis and Fischer esterification of cellulose were conducted under microwave-hydrothermal conditions; meanwhile, TPCA formation was induced by the dehydration reaction between L-cysteine and citric acid. The effects of the reaction temperature and reaction time on the yield and performance of FCNF were investigated. The morphology and size, surface chemical property, crystal structure, thermostability, and fluorescent performance of FCNF were characterized. The results revealed that the yield of FCNF reached 73.2% under a microwave power of 500 W, reaction temperature of 110 °C, and reaction time of 5 h. The FCNF obtained presents a short rod-like morphology. The crystallinity of the FCNFs is 80%, and their thermal stability did not decline significantly. Additionally, the fluorescent performance of the FCNFs is excellent, which results in them having good sensitivity to chloride ions. The good fluorescent performance and significant responsiveness to chloride ions of FCNFs lead to them having broad prospects in bio-labeling, biosensing, information storage, chloride ion detection, among others. [ABSTRACT FROM AUTHOR]

A new camera calibration technique based on serious distortion is proposed, which only requires the camera to observe the plane pattern in an arbitrary azimuth. It uses the geometrical imaging principle and radial distortion model to acquire radial lens distortion coefficient and the image coordinate (u0, v0), and then solves the linear equation aiming at the other parameters of the camera. This method has the following characteristics: Firstly, the position of the camera and the plane is arbitrary, and the technique needs only a single observation for plane pattern. Secondly, it is suitable for camera calibration with serious distortion. Thirdly, it does not need expensive ancillary equipment, accurate movement, or lots of photos observed from different orientations. Having been authenticated by computer emulation and actual experiment, the results of the proposed technique have proved to be satisfactory. The research has also paved a new way in camera calibration for further studies. [ABSTRACT FROM AUTHOR]

The mechanical behavior of the steel–concrete joints in a composite bridge was investigated. Pull-out tests on eight specimens were carried out to evaluate the connection performance of Perfobond rib shear connectors (PBL shear connectors). In addition, static load tests were conducted on three composite joint specimens with a scale of 1/2 in a composite truss bridge. The crack load, load–displacement curves, strain distribution, and the joint stiffness were obtained from the composite joint to analyze the mechanical behavior of steel–concrete joints. The experimental results show that the embedded depth plays an important role in the ultimate bearing capacity and the deformation of PBL shear connectors and could even change the failure mode. Based on the test results of composite joints, the displacement increased almost linearly with the horizontal load on the concrete chord. There was no evident failure, and large deformation occurred in composite joints. In addition, the ultimate loads obtained from three composite joint specimens were greater than 2.93 times the design load (2050 kN). These investigated composite joints had excellent bearing capacity (above 6000 kN). This study will provide an experimental reference for the design of steel–concrete joints for composite truss bridges. [ABSTRACT FROM AUTHOR]

Polymer processes often contain state variables whose distributions are multimodal; in addition, the models for these processes are often complex and nonlinear with uncertain parameters. This presents a challenge for Kalman-based state estimators such as the ensemble Kalman filter. We develop an estimator based on a Gaussian mixture model (GMM) coupled with the ensemble Kalman filter (EnKF) specifically for estimation with multimodal state distributions. The expectation maximization algorithm is used for clustering in the Gaussian mixture model. The performance of the GMM-based EnKF is compared to that of the EnKF and the particle filter (PF) through simulations of a polymethyl methacrylate process, and it is seen that it clearly outperforms the other estimators both in state and parameter estimation. While the PF is also able to handle nonlinearity and multimodality, its lack of robustness to model-plant mismatch affects its performance significantly. [ABSTRACT FROM AUTHOR]

In this work, 1060 pure aluminum was subjected to high rotating speed submerged friction stir processing (HRS-SFSP). The heat cycle curve of the processing area was measured by K-type thermocouple and temperature recorder. The microstructure, grain size, texture, and tensile fracture of the processing area were analyzed by electron backscattered diffraction and scanning electron microscopy. The results show that the HRS-SFSP caused severe plastic deformation of 1060 aluminum and produced fine recrystallized grains. The minimum average grain size was 0.686 μm at the 2-pass. In addition, the dislocation density in the stirred region was greatly reduced and the high angle grain boundaries (HAGBs) were dominant. The texture strength of pure aluminum increased with the increase in processing passes. The maximum hardness of 66.3 HV and ultimate tensile strength of 95.2 MPa were obtained at 1-pass, which were 86% and 33.9% higher than those of the base material, respectively. The hardness and strength of the stirring zone (SZ) decreased with the increase in the number of processing passes. Therefore, HRS-SFSP pure aluminum can obtain high strength and hardness while maintaining good plasticity. [ABSTRACT FROM AUTHOR]

The relationships between crop yield and its selected related impact factors has often been explored using ordinary least squares regression (OLSR). However, this model is non-spatial and non-robust. This study first used stepwise regression to identify the main factors affecting winter wheat yield from twelve potential related factors in Yucheng County, China. Next, robust geographically weighted regression (RGWR) was used to explore the spatially non-stationary relationships between wheat yield and its main impact factors. Then, its modeling effect was compared with that of GWR and OLSR. Last, robust geostatistical analysis was conducted for spatial soil management measures in low-yield areas. Results showed that: (i) three main impact factors on wheat yield were identified by stepwise regression, namely soil organic matter, soil total phosphorus, and pH; (ii) the spatially non-stationary effects of the main impact factors on wheat yield were revealed by RGWR but were ignored by OLSR; (iii) RGWR obtained the best modeling effect (RI = 52.31%); (iv) robust geostatistics obtains a better spatial prediction effect and the low-yield areas are mainly located in the northeast and the middle east of the study area. Therefore, the integrated yield-based methodology effectively improves soil nutrient management at a regional scale. [ABSTRACT FROM AUTHOR]

Auxiliary data has usually been incorporated into geostatistics for high-accuracy spatial prediction. Due to the different spatial scales, category and point auxiliary data have rarely been incorporated into prediction models together. Moreover, traditionally used geostatistical models are usually sensitive to outliers. This study first quantified the land-use type (LUT) effect on soil total nitrogen (TN) in Hanchuan County, China. Next, the relationship between soil TN and the auxiliary soil organic matter (SOM) was explored. Then, robust residual cokriging (RRCoK) with LUTs was proposed for the spatial prediction of soil TN. Finally, its spatial prediction accuracy was compared with that of ordinary kriging (OK), robust cokriging (RCoK), and robust residual kriging (RRK). Results show that: (i) both LUT and SOM are closely related to soil TN; (ii) by incorporating SOM, the relative improvement accuracy of RCoK over OK was 29.41%; (iii) by incorporating LUTs, the relative improvement accuracy of RRK over OK was 33.33%; (iv) RRCoK obtained the highest spatial prediction accuracy (RI = 43.14%). It is concluded that the recommended method, RRCoK, can effectively incorporate category and point auxiliary data together for the high-accuracy spatial prediction of soil properties. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate the cutting performance of amorphous carbon (a-C) coatings and hydrogenated amorphous carbon (a-C:H) coatings on machining 2A50 aluminum alloy. First-principles molecular dynamics simulation was applied to investigate the effect of hydrogen on the interaction between coatings and workpiece. The cross-section topography and internal structure of a-C and a-C:H films were characterized by field emission scanning electron microscopy and Raman spectroscopy. The surface roughness of the deposited films and processed workpiece were measured using a white light interferometer. The results show that the a-C-coated tool had the highest service life of 121 m and the best workpiece surface quality (Sq parameter of 0.23 μm) while the workpiece surface roughness Sq parameter was 0.35 and 0.52 μm when machined by the a-C:H-coated and the uncoated tool, respectively. Meanwhile, the build-up edge was observed on the a-C:H-coated tool and a layer of aluminum alloy was observed to have adhered to the surface of the uncoated tool at its stable stage. An interface model that examined the interactions between H-terminated diamond (111)/Al(111) surfaces revealed that H atoms would move laterally with the action of cutting heat (549 K) and increase the interaction between a-C:H and Al surfaces; therefore, Al was prone to adhere to the a-C:H-coated tool surface. The a-C coating shows better performance on cutting aluminum alloy than the a-C:H coating. [ABSTRACT FROM AUTHOR]

During the past few decades, colorectal cancer (CRC) incidence and mortality have significantly increased, and CRC has become the leading cause of cancer-related death worldwide. Thus, exploring novel effective therapies for CRC is imperative. In this study, we investigated the effect of oncolytic adenovirus CD55-Smad4 on CRC cell growth. Cell viability assay, animal experiments, flow cytometric analysis, cell migration, and invasion assays, and Western blotting were used to detect the proliferation, apoptosis, migration, and invasion of CRC cells. The oncolytic adenovirus CD55-Smad4 was successfully constructed and effectively suppressed CRC cell proliferation in vivo and in vitro. Notably, CD55-Smad4 activated the caspase signaling pathway, inducing the apoptosis of CRC cells. Additionally, the generated oncolytic adenovirus significantly suppressed migration and invasion of CRC cells by overexpressing Smad4 and inhibiting Wnt/β-catenin/epithelial-mesenchymal transition (EMT) signaling pathway. Moreover, CRC cells treated with CD55-Smad4 formed less and smaller spheroid colonies in serum-free culture than cells in control groups, suggesting that CD55-Smad4 suppressed the stemness of CRC cells by inhibiting the Wnt/β-catenin pathway. Together, the results of this study provide valuable information for the development of a novel strategy for cancer-targeting gene-virotherapy and provide a deeper understanding of the critical significance of Smad4 in gene therapy of CRC. [ABSTRACT FROM AUTHOR]

The effects of film thickness on the tribological behavior have been investigated for hydrogen-free diamond-like carbon coating in this paper. The film was deposited on cemented carbide substrate (YG10C) by applying a high power impulse magnetron sputtering (HiPIMS) technique. The reciprocating ball on the disc test was conducted on the film with different thicknesses from 0.66~1.26 μm against the ZrO2 ball. The friction coefficient and wear resistance of the coating with different thickness showed a unimodal change. Numerous defects were observed on the surface of the film with a thickness of 0.66 μm and the wear mechanism was mainly plow-grinding. Therefore, the steady-state friction coefficient reached the maximum value of 0.22. The coating with a thickness of 1.01 μm had a higher sp3 content and a smoother, dense surface. A graphite transfer layer with low shear strength was detected on the ZrO2 ball against the film with a thickness of 1.01 μm, which led to the reduction in friction, thus the steady-state friction coefficient reached the minimum value of 0.10. However, the internal stress of the film increased with increasing thickness due to the distortion of the bond angle of internal structure when the film was bombarded by high-energy particles. The peeling coating was observed under reciprocating sliding, which both played the role of plowing and boundary lubrication film. The steady-state friction coefficient was 0.14 with a coating thickness of 1.26 μm. As a result, the hydrogen-free diamond-like carbon coating with optimized thickness shows a smooth and compact surface, low internal stress, high sp3 content, and better tribological properties. [ABSTRACT FROM AUTHOR]

Although phosphorus (P) is an essential nutrient for biological productivity, it can cause freshwater degradation when present at fairly low concentrations. Monitoring studies using continuous sampling is crucial for documenting P dynamics in freshwater ecosystems and to reduce the risk of eutrophication. Despite literature updates of developments of the analytical methods for measurement of P species in natural waters, there has been no comprehensive review addressing freshwater sample collection, sample preparation, and sample treatment to fractionate and characterize different forms of P. Therefore, this paper aims to elaborate the different techniques for freshwater sampling and to introduce alternative laboratory methods for sample preservation and P fractionation. The advantages and disadvantages of various sampling techniques, including the traditional manual and the recently developed automatic and passive methods, are presented to highlight the importance of collecting representative freshwater samples. Furthermore, we provide suggestions for sample pretreatment, including filtration, transportation, and storage steps to minimize microbial activity and to maximize the accuracy of measurement of various P fractions. Finally, the most common laboratory methods to measure dissolved and particulate as well as the organic and inorganic freshwater P fractions are efficiently provided. Using this guide, a comprehensive monitoring program of P dynamics in freshwater ecosystems can be developed and applied to improve water quality, particularly of P-rich freshwaters. [ABSTRACT FROM AUTHOR]

Rapid filling/emptying of pipes is commonly encountered in water supply and sewer systems, during which pressure transients may cause unexpected large pressure and/or geyser events. In the present study, a linearized analytical model is first developed to obtain the approximate solutions of the maximum pressure and the characteristics of pressure oscillations caused by the pressurization of trapped air in a horizontal pipe when there is no or insignificant air release. The pressure pattern is a typical periodic wave, analogous to sinusoidal motion. The oscillation period and the time when the pressure attains the peak value are significantly influenced by the driving pressure and the initial length of the entrapped air pocket. When there is air release through a venting orifice, analysis by a three-dimensional computational fluid dynamics model using ANSYS Fluent was also conducted to furnish insights and details of air–water interactions. Flow features associated with the pressurization and air release were examined, and an air–water interface deformation that one-dimensional models are incapable of predicating was presented. Modelling results indicate that the residual air in the system depends on the relative position of the venting orifice. There are mainly two types of pressure oscillation patterns: namely, long or short-period oscillations and waterhammer. The latter can be observed when the venting orifice is located near the end of the pipe where the air is trapped. [ABSTRACT FROM AUTHOR]

For patients with disorders of consciousness, such as unresponsive wakefulness syndrome (UWS) patients and minimally conscious state (MCS) patients, their long treatment cycle and high cost commonly put a heavy burden on the patient's family and society. Therefore, it is vital to accurately diagnose and predict consciousness recovery for such patients. In this paper, we explored the role of the P300 signal based on an audiovisual BCI in the classification and prognosis prediction of patients with disorders of consciousness. This experiment included 18 patients: 10 UWS patients and 8 MCS- patients. At the three-month follow-up, we defined patients with an improved prognosis (from UWS to MCS-, from UWS to MCS+, or from MCS- to MCS+) as "improved patients" and those who stayed in UWS/MCS as "not improved patients". First, we compared and analyzed different types of patients, and the results showed that the P300 detection accuracy rate of "improved" patients was significantly higher than that of "not improved" patients. Furthermore, the P300 detection accuracy of traumatic brain injury (TBI) patients was significantly higher than that of non-traumatic brain injury (NTBI, including acquired brain injury and cerebrovascular disease) patients. We also found that there was a positive linear correlation between P300 detection accuracy and CRS-R score, and patients with higher P300 detection accuracy were likely to achieve higher CRS-R scores. In addition, we found that the patients with higher P300 detection accuracies tend to have better prognosis in this audiovisual BCI. These findings indicate that the detection accuracy of P300 is significantly correlated with the level of consciousness, etiology, and prognosis of patients. P300 can be used to represent the preservation level of consciousness in clinical neurophysiology and predict the possibility of recovery in patients with disorders of consciousness.

Ziyuglycoside II is one of the major active compounds of Sanguisorba officinalis L., which has a wide range of clinical applications including hemostasis, antibiosis, anti-inflammation and anti-oxidation. This study investigated the effect of ziyuglycoside II on the growth of human breast carcinoma MDA-MB-435 cells for the first time. The results showed that ziyuglycoside II could significantly inhibit the growth of MDA-MB-435 cells through blocking cell cycle progression at G0/G1 and S phase as well as via inducing cell apoptosis. Accumulation of reactive oxygen species (ROS) was observed in the progression of cell cycle arrest, which was associated with the increased expression of cell cycle regulating factors, p53 and p21. Subsequent apoptosis induced by ziyuglycoside II was accompanied with the activation of mitochondrial pathway, in particular a decreased mitochondrial membrane potential (MMP) as well as increased Bax/Bcl-2 ratio, cytochrome c release and the activity of caspase-3 and caspase-9. In conclusion, our study was the first to report that ziyuglycoside II has inhibitory effect on the growth of MDA-MB-435 cells, which might become a potential therapeutic approach of breast cancer in the future.