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The MoS 2 -based mixed matrix membranes (MMMs) exhibited excellent pervaporation separation for aromatic compounds, but the narrow interlayer spacing and few affinity sites in MoS 2 limited the simultaneous improvement in the total flux and separation factor. Therefore, constructing 2-PE transport channels and affinity sites in MMMs is of significant importance to improve the pervaporation separation performance. Herein, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (IL) was intercalated into the interlayer of the molybdenum disulfide (MoS 2) under electrostatic and concentration diffusion interactions to obtain IL@MoS 2. Then, IL@MoS 2 was incorporated into polydimethylsiloxane (PDMS) to prepare MMMs for efficient 2-PE separation, which had good miscibility with polymer matrix. The total flux, separation factor and pervaporation separation index of as-prepared MMMs reached 1466 g m−2 h−1, 33 and 47,571 g m−2 h−1, separately, which increased by 26 %, 31 % and 44 % compared with that of PDMS embedding with MoS 2. This is because IL@MoS 2 in MMMs not only can afford 2-PE transport channels, but also provide 2-PE affinity sites due to the hydrogen bonds and π-π interactions, which promotes the solubility of 2-PE in MMMs. When the concentration of maltol increased to 1500 ppm in 2-PE aqueous solution, the 2-PE flux and separation factor of 2-PE/water only decreased by 23 % and 26 %, revealing that MMMs had good 2-PE selectivity in 2-PE/maltol/water mixture. In addition, it displayed exceptional durability during 168 h testing, demonstrating that this membrane had a good application prospect for 2-PE separation. [Display omitted] • The interlayer spacing of MoS 2 was regulated by intercalation modification of IL to prepare IL@MoS 2. • IL@MoS 2 was incorporated into PDMS to engineer MMMs for 2-PE pervaporation separation. • IL@MoS 2 in MMMs intensified 2-PE pervaporation separation due to the hydrogen bonds and π-π interactions. • MMMs had a flux of 1466 g m−2 h−1 with a separation factor of 33 which was higher than that embedded with MoS 2. [ABSTRACT FROM AUTHOR]

• The new digital shearography meets the requirements of high standards, making it suitable for dynamic tests while providing high-quality phase maps. • Both shearing direction and amount can be controlled quantitatively and accurately. • Phase maps can be evaluated with a single exposure. • High light efficiency and accurate phase demodulation lead to high-quality phase maps. Digital shearography (DS), a laser-based optical interferometric method, is widely employed for measuring the first-order derivative of an object's surface deformation. Unlike digital holography, DS integrates self-reference optics, enhancing resistance to environmental disturbance and improving detection sensitivity, making it ideal for non-destructive testing (NDT). DS finds applications in diverse fields such as material inspection, fluid property research, medical diagnostics, cultural heritage restoration, and military defense. The conventional temporal phase-shift (TPS) method encounters limitations in dynamic tests, leading to the introduction of the spatial phase-shift (SPS) method. However, SPS is restricted by aperture size, impacting the phase map quality. The spatial light modulator (SLM) introduces a novel approach to DS system development, enabling quantitative shearing adjustments through precise SLM control. Existing DS systems using traditional phase-shift technology rely on interferometers and struggle to achieve high-quality phase maps with a single exposure. The proposed high-performance DS, leveraging both SLM and a micro-polarizer camera, overcomes this limitation, facilitates single-exposure phase map evaluation with the polarization phase-shift technique, and eliminates the need for a tiny aperture, enhancing light beam utilization and phase map quality. [ABSTRACT FROM AUTHOR]

• Multi-level point cloud processing scheme that significantly improves the quality of point cloud fusion. • The solution has the ability to process static and dynamic multi-view point clouds. • Digital image correlation can easily generate enough point cloud data. Post-processing of the initial point cloud is one of the important ways to improve the measurement accuracy of digital image correlation (DIC). In this study, a multi-level point cloud optimization scheme is proposed for processing point clouds of multi-view images in DIC systems. Dense point clouds obtained after interpolation of primary point clouds from multi-view images contain noise. First, the local Random Sample Consensus (RANSAC) algorithm is proposed to retain local features while removing coarse matching points. Defects are filled in by the adaptive cavity repair technique based on information around the cavities and restores the original surface shape to the greatest extent. Finally, a multi-layer surface filtering is executed to smooth the mesh. Experiments verify the comprehensive performance of the multi-level optimization scheme, providing excellent results in point cloud fusion, cavity repair, and mesh smoothing, regardless of static 3D reconstruction or dynamic deformation measurement. [ABSTRACT FROM AUTHOR]

An ocean trench is a major surface feature of a subduction zone, formed by the subduction of a lithospheric plate into the mantle. Despite the importance of ocean trench depth, the primary factors controlling it have not been systematically studied. In this study, we collected several global datasets and performed stepwise regression analysis to investigate this issue. Bathymetric data illustrate that the maximum depth of global trenches varies from −3282 m to −10,924 m, with an average depth of −6125.8 m. Global trench depth generally follows a normal distribution, but also shows a bimodal pattern. Our analysis results suggest that slab age (A s), slab dip (θ s), sediment thickness (T sed), and crust thickness (T c) within a trench are the primary factors controlling global trench depth. The influence of A s , T sed , and T c on trench depth is similar and is much greater than that of θ s. Collectively, these four factors account for 77 % of the variation in trench depth, and other factors including data resolution, reheating events on the seafloor or dynamic topography may account for the remaining 23 % of the trench depth variation. Hierarchical cluster analysis indicates that when a trench enters a terminal stage, its exceptionally thick T sed and T c will cause the trench depth to significantly shallow, irrespective of how strongly the A s and θ s vary. Prior to this, the trench depth is mainly controlled by A s and θ s because T sed and T c are generally small. Our study also reveals varying degrees of correlation between trench depth and subduction zone kinematic parameters including subducting plate velocity (V subn), upper plate velocity (V upn), thermal parameter (φ), trench migration velocity (V tn), subduction velocity (V sn), back-arc deformation rate (V d), and subduction polarity (P sub). There seems to be no correlation between subduction duration (T sub) and trench depth. We consider these linkages between trench depth and subduction kinematic parameters are the result of the correlations between these parameters and A s , θ s or T sed in trenches. • This study analyzes global trench depths and their controlling factors. • High-resolution global seafloor bathymetric data make this analysis possible. • Slab age, slab dip, thickness of sediment and crust primarily control trench depth. • We identified five clusters of global trenches based on four controlling factors. • Trench depth is also indirectly linked to subduction zone kinematic parameters. [ABSTRACT FROM AUTHOR]

• A high precision roll angle measurement method based on digital holography is proposed. • This method requires only a single hologram to obtain the phase of two object beams, thus enabling dynamic measurement of the roll angle. • Relying on the rough surface of the measured object, this method does not require the installation of a target on the measured object. • Based on the numerical reconstruction principle of digital holography, there is no need to adjust the imaging system to refocus when the measurement distance changes. Among the six degrees of freedom for a moving body, measuring roll angle is the most difficult. In this study, a noncontact, no-imaging dynamic roll angle measurement system based on holography is proposed. Two beams of light are used to irradiate the measured object symmetrically, then two reflected light and the reference light interfere with each other to produce a hologram. By extracting the phase information of the two reflected light from two illumination beams using single hologram, this method achieves dynamic measurement of in-plane deformation, and then the roll angle is obtained through subsequent data processing. The effectiveness of the proposed method in-plane roll angle measurement is validated based on theoretical and experimental results. Experimental results show that the proposed method measures roll angle with high accuracy at both fixed and varied distances. [ABSTRACT FROM AUTHOR]

Carbon molecular sieve (CMS) membranes are widely used for the separation of similar molecular kinetic diameter gas. However, their performance is limited by a large amount of discontinuous porous structures and a few adsorption affinity sites. Herein, we first prepared magnetic Co@NC@ZIF-8 nanoparticles, followed by introducing it into the polyimides matrix to design precursor membrane with vertical nanochain-like particle distribution by magnetic field induction. Afterwards, hybrid carbon molecular sieve (HCMS) membranes were prepared by pyrolyzing precursor with high-temperature under N 2 atmosphere, which had ordered microporous architecture and Co-N-C structure. Resultant HCMS membranes prepared by magnetic field induction had excellent gas separation performance, whose CO 2 , N 2 and CH 4 permeabilities were 27,050, 2614 and 622 Barrer, with CO 2 /N 2 , CO 2 /CH 4 and N 2 /CH 4 selectivities of 10.4, 43.5 and 4.2 respectively. These values far exceeded 2019 CO 2 /CH 4 and 2008 N 2 /CH 4 upper bounds as well as approached 2008 CO 2 /N 2 upper bound. The superior performance resulted from the vertically ordered nanochain-like channels for gas transport, which dramatically shortens the transport path of gas molecules to intensify shape sieving potential. Moreover, the Co-N-C structure on the wall of channels could facilitate CO 2 transport due to the π complexation. Additionally, a large quantity of nitrogen sites in the carbonized Co@NC@ZIF-8 enhance CO 2 adsorption selectivity owing to the acid-base interaction. More remarkably, after 30-day aging testing, it was found that HCMS membranes prepared by magnetic field induction had exceptional aging resistance compared to the pristine CMS membranes and one without magnetic field induction under the same aging environments. [Display omitted] • HCMS membranes hybridized by magnetic Co@NC@ZIF-8 core-shell were designed by magnetic field induction. • The Co-N-C structure could cause π complexation with CO 2 to implement facilitated transport. • M-CMS/Co@NC@ZIF-8 had CO 2 permeability of 27,050 Barrer with CO 2 /CH 4 and N 2 /CH 4 selectivity of 43.5 and 4.2 respectively. • Ordered nanochain-like channels can inhibit the aging of HCMS membranes. [ABSTRACT FROM AUTHOR]

Highlights • We propose an error elimination method for thermal disturbance in high-temperature environment using color speckle and camera instead of traditional industrial camera. • This measurement method is simpler and easier, and the accuracy and practicability of the measurement are higher than the existing methods. • All the advantages of digital image correlation method, including simple structure, non-contact and full field measurement. • No stringent synchronization is required because what we process is the grayscale information of different channels of each picture. • Suitable for any complex high temperature environment. Abstract Digital image correlation method is a kind of displacement and strain measurement technique based on visible light illumination. It can realize non-contact and full-field measurement with lower requirements on the measurement environment, thus it's widely used in testing and research for mechanical properties of materials at high temperature. But there are many factors affecting the measurement accuracy due to the complexity of the high temperature environment, of which the influence of the thermal disturbance on digital image correlation method is the most obvious. In order to reduce the influence of it and improve the measurement accuracy, this paper proposes a measurement method for eliminating thermal disturbance error in high temperature deformation measurement based on color speckle and camera. Two kinds of grayscale field information of different colors were endued to the surface of specimen, and we collected images by color camera with channel separation for each frame of them. Then we processed the grayscale field of two channels separately combined with the digital image correlation method, analyzed the information carried by two different grayscale fields, and a simple mathematical model was performed to separate the thermal disturbance error from the measurement results. Finally, we set up the experimental system, built the mathematical model between the two channels through static measurement experiment, which was used to extract and correct the thermal disturbance error of measurement results of the rigid body motion experiment. The high consistency between corrected result and true displacement value proved the feasibility and accuracy of the proposed method. [ABSTRACT FROM AUTHOR]

Highlights • Specular surface is illuminated by scattered light to generate speckle patten. • The sensitivity factor is influenced by surface normal of the specular surface. • The specular surface is conjugated to the interferogram in the optical setup. • Defects below specular surface is detected by the proposed shearography. Abstract Shearography has been widely used in non-destructive testing due to its advantages of fast, full-field, and high sensitivity for nondestructive test and strain measurement. Shearography has been applied successfully to various industry applications. However, traditional shearography requires the surface under test to be sufficiently rough. This study presents a modified shearography setup that can be applied to workpieces with specular surface which is illuminated by light scattered from a rough plane to generate speckle patten. In the optical setup, the specular surface is conjugated to the phase map to simplify the positional correspondence between the interferogram and the internal defects. The sensitivity factor is analyzed through ray tracing method based on geometric optics which is influenced by the surface normal. The experimental results are described and presented as well. [ABSTRACT FROM AUTHOR]

Highlights • The SLM can change the phase of the light and the amount of shear. • The nonlinear random error in phase shift method can be eliminated. • The efficiency of detection can be greatly improved. Abstract The paper presents a new shearography system which applies a spatial light modulator (SLM). The system can control the shearing amount and direction as well as introduce the phase shift accurately and automatically, making shearographic testing easier and more practical. Shearography has the known advantages for nondestructive test and strain measurements of being fast, full-field, and having high sensitivity. Traditionally, the shearing amount is controlled by adjusting a reflector mechanically. Mechanical adjustment of the reflector is slow, inconvenient and not well suited for in-field NDT practice. For application of phase shift techniques, a piezoelectric transducer (PZT), which is usually used for application of phase shift techniques, introduces random error due to its tendency to be nonlinear. This paper introduces a new shearographic detection system with a spatial light modulator. The spatial light modulator controls the liquid crystal by using a birefringence effect and twisted nematic effect. The spatial light modulator can change the phase of the light and shearing amount accurately and automatically, thus eliminating the nonlinear random error in the phase shift method. Furthermore, this system also improves testing efficiency. In this paper, the fundamental of SLM shearography is presented. The capability of this optical configuration is demonstrated theoretically as well as through experiments. [ABSTRACT FROM AUTHOR]

Abstract Polyaniline-decorated halloysite nanotubes (PANI-d-HNTs) having a multilayer hollow tubular structure were incorporated into sulfonated poly(ether ether ketone) (SPEEK) to prepare high-performance mixed matrix membranes (MMMs) for CO 2 /N 2 separation. Scanning electron microscopy images revealed that PANI-d-HNTs were tightly wrapped by SPEEK chains. The strong interfacial interaction between PANI-d-HNTs and SPEEK, as confirmed by attenuated total-reflectance Fourier-transform infrared spectroscopy and differential scanning calorimetry, led to excellent miscibility between the polymer and halloysite nanotubes, which in turn, resulted in improved mechanical properties for the MMMs. The highest CO 2 permeability of 1260 Barrer and a CO 2 /N 2 selectivity of 87 were achieved for MMMs loaded with 0.9 wt% PANI-d-HNTs; these values exceeded the Robeson's upper bound proposed in 2008, and were also much higher than those of MMMs containing 0.9 wt% HNTs, for which, a CO 2 permeability of 1093 Barrer and CO 2 /N 2 selectivity of 74 were observed. It is proposed that PANI-d-HNTs with a multilayer hollow tubular structure can be used as high-speed facilitated channels for CO 2 transport, where densely arranged secondary amine groups readily reacted with CO 2 to facilitate transport in the MMMs. Importantly, durability testing indicated that MMMs loaded with 0.9 wt% PANI-d-HNTs maintained outstanding CO 2 permselectivity for over 120 h, suggesting the superior stability of the membranes under mixed gas feed conditions. Graphical abstract fx1 Highlights • Hollow tubular PANI-d-HNTs were introduced to SPEEK membrane for CO 2 transport. • The CO 2 permselectivity of MMMs was higher than that of the pure SPEEK membrane. • High-speed CO 2 transport channels in MMMs contributed to high CO 2 permselectivity. • The densely arranged amine groups present on channels can facilitate CO 2 transport. • Good compatibility between PANI-d-HNTs and polymer matrix was obtained in MMMs. [ABSTRACT FROM AUTHOR]

Abstract Smartly coupling exonuclease-induced target recycling signal amplifications with β-cyclodextrin host-guest recognition, a novel "signal-on" aptamer sensor for sensitive determination of ochratoxin A (OTA) was proposed for the first time. Firstly, the formation of double-strand DNA (dsDNA) was occurred by hybridizing OTA aptamer with its complementary DNA (cDNA) and as the probe DNA the cDNA at its 3′ terminal was labeled with methylene blue (MB). Next, when OTA was present, the aptamer tended to form aptamer-OTA complex with conformation of G-quadruplex instead of aptamer-cDNA duplex, leading to thus the probe DNA separating from dsDNA complex. Then the RecJf exonuclease was added, demolishing partially G-quadruplex structure and releasing a certain number of OTA. Sequentially, those released OTA would continue to react with the rest of aptamer in dsDNA, drawn into development of a new round of G-quadruplex complex, where the target cycling was realized. Meanwhile, as a signal molecule, MB modified on cDNA was liberated along with the cDNA being digested into monoucleotides by RecJf exonuclease, capable of diffusing onto the electrode surface due to host-guest recognition with β-cyclodextrin, whereupon the signal was enriched and yielded. In this way, cycles of target with continuous output of signal indicators were undergone, in which the detection of target was in return fulfilled with signal amplification owing to the joint endeavor of exonuclease and β-cyclodextrin. Under the optimal conditions, the raising signal maintained a linear relation with the logarithm of the target concentrations ranging from 10 pg/mL to 10.0 ng/mL and the detection limit reached as low as 3 pg/mL. This brand-new strategy was simple and low-cost but satisfactory in terms of detection limit, range and sensitivity, in all possibility to be applied extensively for diverse targets detection by easily alternating the corresponding aptamers. Highlights • A well-performed ochratoxin A aptasensor was proposed using exonucleases and β-cyclodextrin. • The employment of RecJf exonuclease triggered the target cycling and signal amplification. • The host-guest recognition with β-cyclodextrin facilitated capturing signal molecules, enabling the signal enrichment. • The selectivity was ensured by the adoption of aptamer. [ABSTRACT FROM AUTHOR]

Highlights • Baicalin largely alleviated the symptoms of systolic and diastolic pressures and reduced urine protein. • Baicalin protected against liver and kidney cells apoptosis. • Baicalin effected the apoptotic proteins expression of liver and kidney tissue in JEG-3 cells and rat preeclampsia model. Abstract The incidence of acute liver and kidney injury in pregnancy is companied by Preeclampsia (PE), which has remained a major cause of maternal and fetal morbidity, and mortality. Therefore, a significant treatment to protect against liver and kidney injury of PE requires new drugs to develop potential therapeutic benefits to the clinic. Baicalin played protection role on inhibition of cell apoptosis which is a potential drug for keep liver and kidney from acute injury on PE patients. In this study, we made PE rat disease model with liver and kidney acute injury, and then used low-, medium-, and high-dose of Baicalin to treat PE rat, respectively. We found that Baicalin attenuated acute injury symptoms and inhibited apoptosis of rat liver and kidney tissues. The intervention of Baicalin increased the expression of anti-apoptotic protein XIAP and Bcl-2, reduced the expression of apoptotic protein Caspase-9 in rat liver; and similarly, Baicalin increased the expression of Bcl-2, while inhibited Caspase-9 and AT1 in rat kidney. Interestingly, Baicalin intervention with medium dose showed a better function for inhibiting apoptosis. Our data suggests that Baicalin is a potentially therapeutic candidate for preventing liver and kidney damage, which shed a light on therapeutic benefit for PE rat models. [ABSTRACT FROM AUTHOR]

Highlights • An osmotic-tolerant mutant was obtained by high-throughput screening technology. • Fatty acid composition and intermediates contributed to improve osmotic tolerance. • 248 g/L glucose was totally consumed by neutralizing agent combination strategy. • 223.7 g/L lactic acid was produced with an overall productivity of 5.53 g/L/h. • Open fermentation was carried out for highly efficient lactic acid production. Abstract High titer, productivity and yield are the main pre-requisites of an efficient lactic acid production process. However, the hyperosmotic stress inhibits cell metabolism in the later phase of fermentation. In this study, an osmotic-tolerant mutant named Lactobacillus paracasei NCBIO01-M2 was obtained through a high-throughput screening technology, which exhibited a higher tolerance to osmotic stress due to its more flexible regulation of the unsaturated fatty acid proportion along with the intracellular compatible solute pools. The mutant successfully consumed all 248 g/L initial glucose and produced 223.7 g/L lactic acid with a productivity of 5.53 g/L/h in a single batch fermentation by the neutralizing agent strategy. Moreover, similar fermentation performances were also achieved in the open fermentation mode without sterilization by the mutant, which suggested that the mutant would be a potential for cost-effective commercial lactic acid production. [ABSTRACT FROM AUTHOR]

Abstract A novel aptamer sensor for ratiometric ochratoxin A (OTA) detection was constructed based on the host-guest competition mode. Firstly, the aptamer modified with methylene blue (MB) at its terminal was fixed on the surface of the gold electrode via the host-guest recognition with β-cyclodextrin (β-CD). Then the MoS 2 nanosheets/Au NPs nanocomposites were used for the signal amplification. When OTA was present, the configuration of MB-aptamer transformed from vertical linear to G-quadruplex, thus making itself unable to get close to the electrode surface and causing a decrease in the redox current of the MB-aptamer. Whereas the free ferrocenecarboxylic acid could recognize and occupy the vacant site and produce signals in the current, resulting in the “ratiometric” effect. Consequently, on the basis of the “dual-signal” principle, a highly sensitive detection of OTA was made, indicating that the OTA concentration had a linear response to the signal of sensor between 0.1 nM and 50 nM, and as low as 0.06 nM OTA had been detected. Overall, this method for OTA detection was constructed easily with high sensitivity and specificity, providing a significant platform for highly efficient detection of OTA in biological samples. Graphical abstract Image 1 Highlights • A novel electrochemical sensor for ochratoxin A detection was developed. • MoS 2 nanosheets-Au NPs nanocomposites were used for the signal amplification. • OTA aptamer ensures the specificity of detection. • The merit of β-CD with superior recognition capability was employed. • The ratiometric strategy could avoid the majority of the interferences and maintain higher precision. [ABSTRACT FROM AUTHOR]

Mixed matrix composite membranes (MMCMs) integrate the merits of inorganic and organic materials, but the tortuous transport passageways bring about large transfer mass resistance for gas transport. Herein, we prepared polyethylenimine-functionalized halloysite nanotubes (PEI-HNTs) by the electrostatic self-assembly of positively charged polyethylenimine and negatively charged halloysite nanotubes. Blending as-obtained PEI-HNTs with polyvinylamine (PVAm), MMCMs were prepared by casting above mixed solution on the top of ultrafiltration polysulfone (PSf) support. PEI-HNTs had good miscibility with PVAm due to hydrogen bonding. MMCMs (1 wt% PEI-HNTs loading) exhibited exceptional separation performance (CO 2 permeance: 179 GPU; CO 2 /N 2 selectivity: 127.9), respectively, which were 1.4 and 2.3 times that of MMCMs embedding with 1 wt% HNTs. Noticeably, its value was beyond those of MMCMs incorporating with reported hollow tubular filler as well as other shape filler. This is due to the fact that PEI on the surfaces of HNTs provides a lot of amine carriers, which facilitate CO 2 transport. More importantly, the transport passageways are continuous, thus presumably reducing the CO 2 transfer resistance compared to other shape inorganic material filled-MMMs. Besides, resultant MMCMs revealed desirable stability for over 360 h, with a CO 2 /N 2 mixture as feed gas. Remarkably, it maintained superior gas separation performance (CO 2 permeance of 126 GPU; CO 2 /N 2 selectivity of 88.6) under the acidic conditions. [Display omitted] • PEI-functionalized halloysite nanotubes were blended with PVAm to prepare MMCMs for CO 2 separation. • PEI-functionalized halloysite nanotubes functioned as the continuous CO 2 facilitated transport channels. • MMCMs exhibited excellent CO 2 separation performance under the acidic conditions. • MMCMs had a CO 2 permeance of 179 GPU with a CO 2 /N 2 selectivity of 127.9. [ABSTRACT FROM AUTHOR]

People with dementia experience a high prevalence of comorbidities that seriously affect patient outcomes. The aim of this study was to map the evidence and components related to comorbidity management, including interventions to facilitate and support the practice of management. A scoping review was conducted. In June 2022, PubMed, Web of Science, Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL), The National Institute of Health and Care Excellence (NICE), Open grey, and the Cochrane Library were searched to identify relevant literature. The inclusion criteria were outlined to identify studies on comorbidity management in people with dementia. We found 43 items that met the inclusion criteria. The majority of the studies were published since 2010. Most research focused on medication management, health care service use and provision, and comorbidity-related monitoring and management; there were a small number of studies that involved decision-making. Only 6 studies developed interventions to support dementia care, which included comorbidity management. Studies involving the comorbidity management process were mainly based on qualitative methods, which make it difficult to quantify the impact of these processes on comorbidity management. Given the serious impact of dementia on managing comorbidities, there is a need to develop systematic interventions targeting the management of comorbidities. • Studies have focused on medication management, health care service, monitoring and management, and decision-making. • Communication acts as a glue for self-management, family support and health care support. • There are very few studies that test interventions to support the management of comorbidities among people with dementia. [ABSTRACT FROM AUTHOR]

Yellow Sea current conditions during the late Marine Isotope Stage 3 (late MIS3, 40–30 ka B.P.) highstand remain unknown. Here, environmental magnetism, geochemistry, particle size, and scanning electron microscope methods are employed to analyze core YS01A with a basal age of 40 kyr from the South Yellow Sea mud deposits. Greigite formed in marine sedimentary layers with thickness >7 m during early diagenesis. Greigite formation is related to the redox state and total organic content (TOC) availability, which are controlled, respectively, by the Yellow Sea Cold Water Mass (YSCWM) and the Yellow Sea Warm Current (YSWC). In MIS1 (7–0 ka B.P.), a strong YSWC brought greater TOC, and a strong YSCWM (thickness of 48 m) resulted in a strongly reducing low-oxygen environment. This led to massive magnetite dissolution and pyrite preservation. In late MIS3 (37–31 ka B.P.), the weak Kuroshio Current and East Asian Winter Monsoon (EAWM) resulted in a low-intensity YSWC that provided less TOC. A weak YSCWM (thickness of 35 m), caused by shallow water depths and a weak EAWM, contributed to a less reducing sedimentary environment. Thus, pyritization was interrupted and greigite was preserved. Greigite content can, thus, be used to trace the development of Yellow Sea currents. During a period of slow sea level rise at 41–37 ka B.P., minor greigite formed with most magnetite being preserved, which indicates that the environment started to become reducing. This can be interpreted as due to initial formation of a thin and weak YSCWM. During the 37–31 ka B.P. highstand, the greigite content increased, which suggests more reducing conditions related to establishment of a thicker and intensified YSCWM. In addition, the greigite content decreased progressively, which may have resulted from YSWC weakening. Our results suggest that greigite can be used as a simple tool to reflect current evolution in the Yellow Sea, which can give a better understanding of continental shelf environment change. • Greigite-bearing layers (7 m) formed in late MIS3 are detected in the Yellow Sea. • Greigite formation is controlled by the total organic content and redox state. • Its content reflects cold water mass and warm current evolution in the Yellow Sea. [ABSTRACT FROM AUTHOR]

In order to analyze the change of static pressure pile characteristics in silt and silty clay with the penetration depth, two PHC pipe piles were penetrated in the field in the actual project, and the research was based on the full section test technology and FBG test technology. The results show that the pile pressure increases with the increase of the pile penetration depth; The change of pile tip resistance is affected by the soil layer hardness; When the pile tip is in the transition stage, the pile tip resistance increases significantly; In the process of pile penetration, the hardness and brittleness of the soil layer will be affected by the pile penetration, and the different soil layers will have different effects on the pile tip resistance of the two piles; When the pile goes deep into the soil, the pile side resistance will change slowly, but it will usually increase. This fluctuation is related to the difference of the soft and hard layers of the soil layer, and will also be subject to performance constraints; The pile end resistance ratio in hard soil will be smaller than that in soft soil, which will further affect the load sharing ratio of the test pile. The test results can provide support for practical engineering technology. • For the purpose of analyzing how jacked pile properties in silty soil and silty clay vary with penetration depth based on full-section test technique and FBG test technique. • Through the test, using the total cross-section test technology continuously collecting the whole process of penetration of pile end resistance, analyses the change rule. • Compared with the traditional test methods and test components, the technology in this paper is more advanced, the data has higher accuracy. [ABSTRACT FROM AUTHOR]

The Software-Defined Network (SDN) provides a more flexible and effectively managed network design for next-generation networking. Network managers can easily manage and regulate the entire network using its programmable central controller architecture. This central controller serves as the focal point for numerous attack vectors due to its centralized structure. However, Distributed Denial of Service (DDoS) attacks against the SDN is the most prominent. The goal of this project is to use a machine learning method to categorize SDN traffic as either attack or normal traffic. Next, the Feature Selection method, such as the Filter-based Fisher score method, Wrapper-based method, and analysis of variables (ANOVA) f-test, is used for finely-granulated detection. Then, a rule-based detection method using the Renyi joint entropy algorithm is employed to detect DDoS attacks on SDN controllers. We manage a public "DDoS attack SDN Dataset" with 23 attributes overall. The dataset includes normal and attack traffic for the Internet Control Message Protocol (ICMP), User Datagram Protocol (UDP), and Transmission Control Protocol (TCP). Except for attributes that specify the target and source machines, the dataset, which contains more than 100,000 recordings, has statistical features such as byte count, duration sec, packet rate, and packet per flow. In the classification process, many classifiers such as Artificial Neural Network (ANN), XGBoost (XGB), Support Vector Machine (SVM), and k-Nearest Neighbor (k-NN) were used. The test results demonstrated the efficacy and efficiency of the suggested strategy using the analysis of variables (ANOVA), which performed better than competing methods across a range of evaluation parameters. [ABSTRACT FROM AUTHOR]

Privacy has emerged as a top worry as a result of the development of zero-day hacks because IoT devices produce and transmit sensitive information through the regular internet. This study suggests a deep neural network (DNN) and federated learning (FL) for an IoT network as well as mutual information (MI) for an effective anomaly detection method. The suggested method is different from the conventional model by use of decentralized on-device data to spot IoT network incursions. The information is kept on localized IoT devices for model training and only modified weights are shared in the centralized FL server is an advantage of integrating FL with Deep learning (DL). It uses the IoT-Botnet 2020 dataset for evaluation. Results demonstrate the efficiency of the DNN-based network intrusion detection system (NIDS) in comparison to the deep learning models with improvement in the accuracy of the model and a reduction in the False Alarm rate (FAR). [ABSTRACT FROM AUTHOR]

In this study, the impacts of oxygen metabolism characterized by oxygen uptake rate (OUR) on lactic acid production in Lactobacillus paracasei were investigated through metabolite profiling and metabolic flux analysis. At growth phase, with the cost of declining lactic acid yield, the cells shifted pyruvate metabolism from lactic acid production to ATP high-yielding acetate synthesis to guarantee sufficient energy supply for cell growth under high OUR condition. When the cells reached to stationary phase, significant glucose metabolism inhibition happened with high OUR level due to much more reactive oxygen species (ROS) accumulation in the cells, which subsequently would attack glycolytic key enzyme, glycerate-3-phosphate dehydrogenase (GAPDH), leading to the substantial limitation of glucose consumption. Moreover, other than glucose metabolism restriction, the decline on metabolic level regulation of lactic acid yield further decreased lactic acid productivity. On the other hand, it was interestingly found that intracellular redox balance was greatly dependent on acetyl-CoA node (acetate/ethanol) in growth phase, and acetoin node (acetoin/2,3-butanediol) in stationary phase respectively. The application of integrated metabolite profiling and metabolic flux analysis highlighted the regulation of energy and redox metabolism in lactic acid production by L. paracasei . [ABSTRACT FROM AUTHOR]

A new simple and highly sensitive electrochemical method for pyrophosphatase (PPase) activity detection was developed based on the peroxidase-like activity of G-quadruplex-Cu 2+ DNAzyme. In the absence of PPase, Cu 2+ could coordinate with pyrophosphate (PPi) to form Cu 2+ -PPi compound. While in the presence of PPase, it could destroy the coordinate compound because PPase catalyzed the hydrolysis of PPi into inorganic phosphate and produced free Cu 2+ , which then could be coupled with G-rich DNA to form G-quadruplex-Cu 2+ DNAzyme. The formation of a mimic enzyme (G-quadruplex-Cu 2+ DNAzyme) was immobilized on the surface of screen-printed gold electrode (SPGE). Using 3, 3′, 5, 5′-tetramethylbenzidine (TMB) as a redox mediator and H 2 O 2 as an enzyme substrate, the DNAzyme catalyzed the reduction of H 2 O 2 to generate quantitative chronoamperometric signal. The catalytic activity of G-quadruplex-Cu 2+ DNAzyme for TMB-H 2 O 2 reaction was proportional to the activity of PPase, based on which, a simple and sensitive turn-on electrochemical method for PPase activity was thus developed for the first time. The chronoamperometric intensity of the system had a linear relationship with the PPase activities in the range of 1.0–50.0 mU/mL and the detection limit could be down to 0.6 mU/mL (S/N = 3). This proposed method was selective, cost-effective and convenient without any labels or complicated operations, which was furthermore applied to screen the inhibitor for PPase with high efficiency. [ABSTRACT FROM AUTHOR]

To address the problem of a large amount of noise in the phase pattern in digital speckle pattern interferometry, which seriously affects the phase reconstruction and measurement precision, a filtering method based on optimized 2D S-transform is proposed in this paper. The optimized 2D S-transform provides high signal-to-noise ratio denoising method by adding tilt factors and translation factors to keep the Gaussian window of the appropriate size at different frequency positions. The analysis results of different frequency fringe pattern denoising show that the criteria metrics indicator signal-to-noise ratio (SNR) of the results of the proposed method can reach at least 14.5435 dB and the criteria metrics peak signal-to-noise ratio (PSNR) can reach at least 19.4555 dB, which has better precision compared with the traditional method and solves the incongruity between the smoothness of low-density fringe and the integrity of high-density fringe. • Compared with the traditional filtering method, the proposed method has better accuracy and higher signal-to-noise ratio. • Compared with the advanced filtering method windowed Fourier transform, the proposed method has advantages in the filtering of variable density fringe phase patterns. • The proposed method solves the incongruity between the smoothness of low-density fringe and the integrity of high-density fringe in phase pattern filtering. [ABSTRACT FROM AUTHOR]

PHC pipe pile cooperated with jacked method is widely used in recent years. The excess pore water pressure of pile-soil interface caused during jacked PHC pipe driving would produce important effect on jacked pile construction and bearing characteristics. Two full scale jacked-in piles are penetrated into the clayey soil and studied by monitoring the law of generation and dissipation of excess pore water pressure. The law of excess pore water pressure with penetration depth and time is also analyzed. From this test results, excess pore water pressure of the pile-soil interface increases to the peak and then begins to decrease, but it remains large. The excess pore water pressure of S1 test pile pile-soil interface decreases from 201.4 kPa to 86.3 kPa, and decreases from 374.1 kPa to 114.3 kPa for S2 test pile. The excess pore water pressure of pile-soil interface rises first at the initial stage of consolidation, and it dissipates when the hydraulic gradient between pile-soil interface and soil around the pile disappears. The dissipation degree of excess pore water pressure reaches from 75% to 85%. The proposed solution provides certain engineering significance for jacked pile construction and bearing capacity design in the clayey foundation. • Through on-site monitoring of the distribution and dissipation of excess pore water pressure at the pile-soil interface, the stress characteristics of the pile-soil interface during the PHC pipe pile sinking process were studied. • The maximum ratio of excess pore water pressure of pile-soil interface to effective pressure of overlying soil is 1.08, and gradually decreases along the pile. • The excess pore water pressure at the pile-soil interface caused by pile sinking is approximately linearly increased with the depth of the soil. • Studying the generation and dissipation of excess pore water pressure at pile-soil interface is helpful to reveal the important characteristics and bearing capacity of pile-soil interface during pile-sinking. [ABSTRACT FROM AUTHOR]

The sources, transport pathways and main distribution limitations of surface sediments were clearly identified in the Bohai Sea (BS) and Yellow Sea (YS) by combining the particle size and magnetic property distribution characteristics. The sediment distribution pattern on shelves is mainly controlled by the sediment sources, which include Huanghe-derived sediments, coastally eroded sediments, old Huanghe and old Changjiang subaqueous delta sediments, and mixed sediments transported by the Yellow Sea Warm Current (YSWC). The distribution pattern of silt reflects the transport pathway and limitation of the Huanghe- and old Huanghe-derived sediments, and the sand distribution reflects the final distribution of the coastally eroded sediments, including the eroded old Changjiang subaqueous delta sediments. In addition to the sediment sources, the complex hydrodynamic pattern on the shelves has an important influence on sediment distribution and transport. The sediment particle size and topography of shelves exert limited control over the sediment distribution. Surface sediment sources in the central South YS (SYS) were identified, with the most important contribution being from mixed sediment sources and a convergence area of finer sediment located at approximately 123°E, 36°N. [ABSTRACT FROM AUTHOR]

Continued population growth and the corresponding increase in consumption will mean increases in the global demand for food crops, especially maize, which is used as a food, feed and bioenergy crop. Optimal nitrogen (N) management for high-yielding maize (>15 Mg ha −1 ) is a challenge because the N demand at post-silking will increase significantly, and synchronization of the N supply with such demand will become more difficult. In this study, treatment variables consisted of one solely urea (split application before sowing and at 6 leaf stage) and two CRU-N (nitrogen from controlled-release urea (CRU))/Urea-N (nitrogen from urea) mixtures (1:2 and 2:1) with one-off application at two N rates (180 kg ha −1 and 240 kg ha −1 ) in two experimental years (2013 and 2014). The results indicated that an one-off application of the blend of CRU and urea before sowing was able to satisfy the N demand of a high-yielding maize system (>15 Mg ha −1 ); the results also showed a greater percentage of N accumulation at post-silking (51%–63%) with the grain yields ranging from 16.9 Mg ha −1 to 19.3 Mg ha −1 ，and one-off application a mixture of CRU and urea with 2:1 at 180 kg N ha −1 achieved the lowest N losses (80 kg N ha −1 and 12 kg N ha −1 ), while a mixture of CRU and urea with 1:2 at 240 kg N ha −1 got highest economic return in both years. This work demonstrates that blending CRU and urea in an one-off application could potentially improve grain yields and create a simpler, more efficient and business-friendly system of high-yielding maize production. [ABSTRACT FROM AUTHOR]

A novel electrochemical sensor for highly sensitive and selective detection of glutathione (GSH) was developed coupled thymine-Hg 2+ -thymine (T-Hg 2+ -T) coordination with mesoporous silica nanoparticles (MSN). Hg 2+ ions could specifically interact with thymine bases to form strong and stable T-Hg 2+ -T complexes. And the electroactive molecules-methylene blue (MB) was sealed in the inner pores of MSN with a unique sequential thymine (T)-rich DNA in the presence of Hg 2+ . After the target was added, the formed duplex DNA T-Hg 2+ -T complex could deform into single-stranded DNA by a competitive displacement reaction, leading to the release of MB entrapped in the MSN. Thus the target-dependent amount of released MB could be conveniently monitored with an n -dodecanethiol modified screen-printed gold electrode. Using GSH as a model target, the proposed assay showed a wide detection ranging from 1.0 nM to 1.0 μM with a detection limit of 0.6 nM. This strategy was simple and universal for various analytes with different competitive displacement ligands, possessing a great potential for convenient biotools testing and commercial application. [ABSTRACT FROM AUTHOR]

Carbon molecular sieve (CMS) membranes have great promise in CO 2 capture. However, tortuous transport passageways restrict the enhancement in the permeability due to the presence of disordered porous structure and dead-end pore. Herein, the growth of ZIF-8 layer on the surface of Fe 3 O 4 formed magnetic core-shell Fe 3 O 4 @ZIF-8 particles, which were fixed into 6FDA/ODA:DABA polyimides under magnetic field-induction to fabricate a precursor membrane with vertically oriented chain-like particles. It was then pyrolyzed to form hybrid carbon molecular sieve (HCMS) membranes with ordered microporous structure under high temperature conditions. The cross-section scanning electron microscopy images and N 2 adsorption for resultant HCMS membranes indicate that Fe 3 O 4 @ZIF-8-derived carbons frameworks were vertically oriented to form the ordered microporous structure, which also had good compatibility with carbon matrix stemmed from 6FDA/ODA:DABA polyimides. The as-prepared HCMS membranes embedded with 5 wt% Fe 3 O 4 @ZIF-8 manifested a highest gas separation performance (permeability of 5130 Barrer; CO 2 /N 2 selectivity of 29; CO 2 /CH 4 selectivity of 48), outperforming the pristine CMS membranes, which were near and beyond 2019 CO 2 /N 2 and CO 2 /CH 4 upper bounds, separately. These good separation performances resulted from vertical chain-like microporous particles, which provided fast transport channels to accelerate CO 2 diffusion rate. In addition, we supposed that Fe 3 O 4 prevent ZIF-8 frameworks from destruction during the pyrolysis and promote the size screening capability. More importantly, this membrane exhibited excellent aging resistance over 30 days aging testing compared to pristine CMS membranes. Therefore, it affords a feasible way for carbon capture from flue gas and natural gas. [Display omitted] • HCMS membranes with ordered microporous structure were engineered by magnetic-induced orientation. • Fe 3 O 4 inhibited the collapse of ZIF-8 frameworks during the pyrolysis. • The oriented chain-like channels for facilitating CO 2 transport were constructed. • HCMS membranes had a CO 2 permeability of 5130 Barrer with the CO 2 /N 2 (CH 4) selectivity of 29 (48). [ABSTRACT FROM AUTHOR]

In view of the problem that the model test of pile jacking cannot reproduce the soil's self-gravity and thus cannot truly reflect the pile jacking force, this paper developed an airbag loading system. The airbag is used to pressurize and simulate the overburden soil weight. The method of subsection pile jacking and coupling is ingenuously adopted to achieve long pile penetration. Because the airbag and pressure can be controlled well, it is convenient to simulate the cohesive soil foundation. The size of the model pile used in the test is larger than that of the usual centrifugal model test pile, so it belongs to large scale model test. The experimental results using this system show that the pile jacking force increases with the increase of penetration depth. The degradation of pile lateral resistance has little impact on pile jacking force. After modification based on the degradation theory of pile lateral resistance, the overall variation law of pile lateral resistance is good, and the difference value generated at the joint of pile segments is basically 0. With the increasing of pile depth, the pile lateral resistance is gradually exerted. The pile end resistance fluctuates with the depth, and accounts for a relatively high proportion of pile jacked force, which is maintained above 50%. The method of pile jacking with airbag loading in this paper provides a new idea for the study of the penetration characteristics of jacked pile. • The paper innovatively simulated the overburden of soil by using the air bag loading method, and at the same time used the large-scale model pile to simulate the pile jacking process in laboratory. • A full-section earth pressure sensor was installed at the end of the model pile to obtain the accurate end resistance during pile jacking. • Through section pile jacking, the pile jacking force, pile end resistance and pile lateral resistance of each section of pile jacking process are analyzed. Finally, the whole pile jacking process is realized by coupling and superposition of the three sections of pile jacking process. • Based on the section pile jacking and pile lateral friction degradation theory, the degradation coefficient of pile lateral friction is deduced, and the force mechanism and influencing factors of pile lateral friction degradation are analyzed. [ABSTRACT FROM AUTHOR]

This paper presents a Dual Directional Sheared Spatial Phase-Shift Digital Shearography (DDS-SPS-DS) system for simultaneous measurement of strains/displacement derivative in two directions. Two Michelson Interferometers are used as the shearing device to create two shearograms, one in the x -shearing direction and one in the y -shearing direction, which are recorded by a single CCD camera. Two lasers with different wavelengths are used for illumination, and corresponding band pass filters are applied in front of each Michelson Interferometer to avoid cross-interference between the two shearing direction channels. Two perpendicular shearing directions in the two measurement channels introduce two different spatial frequency carriers whose spectrums are orientated in different directions after Fourier Transform. Phase maps of the recorded two shearograms can be obtained by applying a windowed inverse Fourier transform, which enables simultaneous measurement of dual directional strains/displacement derivatives. The new system is well suited for nondestructive testing and strain measurement with a continuous or dynamic load. The capability of the dual directional spatial phase-shift digital shearography system is described by theoretical discussions as well as experiments. [ABSTRACT FROM AUTHOR]

Lagos is the old capital and largest port city in Nigeria. There are increased ecological and environmental problems around this coastal area with fast-growing industrialization and a population of 14 million in 2020. In this study, we utilized satellite images to study the shoreline evolution of Lagos Lagoon Barrier coast, Nigeria from 1973 to 2019. The Lagos Lagoon Barrier coast is divided into three sections: Section I (Marginal Lagos), section II (Eko Atlantic City), and section III (Lekki peninsula). Section I coast was stable compared to other sections with around 77% of the section experiencing erosion with the averaging rate of −1.73 m/yr, and the remaining 23% accreting at the rate of +0.57 m/yr throughout the study period. Around 92% of Section II was eroded at the rate of −3.59 m/yr, and 8% of this section accreting at the rate of +4.46 m/yr from 1973 to 2008, with a serious erosion rate of −11.79 m/yr from 1986 to 1999. After the Eko Atlantic City project from 2008 to 2019, Section II experienced advancement up to +92.16 m/yr (53%) and a retreat of up to −6.50 m/yr (47%). Along section III, erosion dominates with around 90% of this section being eroded at the averaging rate of −3.55 m/yr with only 10% accreting at the averaging rate of +1.10 m/yr for the study period. Along the westernmost edge of section III, intense erosion up to +7.10 m/yr dominates and continues eastward of Victoria Island from 2012 to 2019. Furthermore, we recorded shoreline erosion up to −11 m/yr along the Ibeju-Lekki axis and Lagos Free Trade Zone (eastern fringe of section III) from 1999 to 2012. Extrapolating the responsible factors for the shoreline fluctuations along the Lagos Lagoon Barrier coast, this study has identified a combined impact of sea-level rise, limited sediment supplied by longshore current from adjacent rivers due to construction of dams along the several tributaries in the Bight of Benin, hard coastal engineering procedure such as the Eko Atlantic City (section II) and Lekki deep seaport projects, and intensified population along the coastline to have contributed to the erosion feature observed along the study area. Moreover, this study has revealed that Eko Atlantic City may have contributed to the eroding coast along section III. Our final deduction shows that section I is dominated by natural shoreline change patterns and therefore primarily responded to the effect of sea-level rise. Section III is influenced by both natural and human forces while section II is influenced by human intervention through coastal protection as a result of reverse-engineering the effect of climate change and sea-level rise. Conclusively, this study has recommended that current coastal management policies and plans in Lagos State need to be reconsidered and revised to ensure the sustainable use of the coastal zone. • 84% of Lagos shoreline has retreated in the last 50 decades at a rate of −2.64 m/yr. • Largest erosion was at Lekki peninsula from 1973 to 1986 at a rate of −12.81 m/yr. • Deepwater ports along the Bight of Benin are the main reason for erosion. • Illegal mining and Eko Atlantic construction also play important roles in erosion. • Coastal engineering and well-planned proactive coastal management strategy are needed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cys-MoS 2 was introduced into Pebax to prepare MMMs for CO 2 /N 2 separation. • The vacancies, defects and amine groups synergically improved CO 2 permeation properties of MMMs. • MMMs exhibited a CO 2 permeability of 297 Barrer with a CO 2 /N 2 selectivity of 120. The incorporation of lamellar materials into polymer matrix can improve the gas separation performance of mixed matrix membranes (MMMs), which have great potential in chemical separation process. However, few intrinsic selectivity sites on MoS 2 sheets suppress further employment in the membrane separation. In this work, the vacancies and defects-containing MoS 2 sheets were prepared by high temperature oxidation and hydrothermal reaction in NaOH solution, and then L-cysteine-functionalized MoS 2 (Cys-MoS 2) was synthesized by a thiol-click chemistry reaction between S vacancies and thiol groups as confirmed by transmission electron microscope (TEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and N 2 absorption. After blending with polyether-block-amide (Pebax), the as-prepared MMMs showed outstanding mechanical properties as a result of the homogeneous dispersion of Cys-MoS 2 and hydrogen bonding between two phases as evidenced by attenuated total reflectance-FTIR, scanning electron microscope (SEM), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The highest permeability of 297 Barrer accompanied with a CO 2 /N 2 selectivity of 120 was obtained for MMMs loaded with 1.5 wt% Cys-MoS 2 , which were enhanced by 206.2 % and 124.7 % over the pristine Pebax membrane, respectively. Meanwhile, this value was superior to that of the previously reported Pebax-based MMMs, transcending 2019 upper bound. The enhanced gas separation performance is due to the improved CO 2 adsorption selectivity by the vacancies and defects of Cys-MoS 2 , while the amine groups carrier enhanced CO 2 reactivity selectivity. [ABSTRACT FROM AUTHOR]

It is well known that two main parameters affect the penetration characteristics of the jacked pile in saturated clay soil area. One is soil breaking resistance at pile end. The other is sliding friction between the pile and soil. In order to study the variation law of pile end resistance with penetration depth in saturated clay, a full-scale in-situ test was conducted. In this test, the less temperature-sensitive gripper jacked pile monitoring system was used. Through the application of this monitoring system, the variation law of pile end resistance with penetration depth was obtained successfully. The test results showed that (1) Based on the field test of two closed-end jacked piles, the feasibility of the developed monitoring system is verified; (2) It is found that the hardness of soil and the change of soil have significant influence on the pile end resistance. (3) When the pile end enters the silty clay layer from the silty clay layer, the pile end resistance increases obviously, and the rapidly growing depth is around 3 d (where d is the pile diameter). Based on FBG, the less temperature-sensitive monitoring system provides a feasible and effective method for the field monitoring of pile jacking. • This paper presents a jacked pile monitoring system based on less temperature-sensitive FBG sensor. • The pile end resistance of jacked pile is studied by field test. • The pile end deformation can be considered as the axial deformation of the clamping support. • The internal relationship between pile end resistance and soil distribution is deeply analyzed. [ABSTRACT FROM AUTHOR]

In this work, we design a new simple and highly sensitive strategy for electrochemical detection of glutathione (GSH) via mercury ion (Hg 2+ ) triggered hybridization chain reaction (HCR) signal amplification. It is observed that in the absence of GSH, a specific thymine–Hg 2+ –thymine (T–Hg 2+ –T) coordination can fold into hairpin structures. While in the presence of GSH, it thus can be chelated with Hg 2+ , resulting in Hg 2+ released from the T–Hg 2+ –T hairpin complex which then forms into ssDNA structure to further hybridize with the surface-immobilized capture DNA probe on the gold electrode with a sticky tail left. The presence of two hairpin helper probes through HCR leads to the formation of extended dsDNA superstructure on the electrode surface, which therefore causes the intercalation of numerous electroactive species ([Ru(NH 3 ) 6 ] 3+ ) into the dsDNA grooves, followed by a significantly amplified signal output whose intensity is related to the concentration of the GSH. Taking advantage of merits of enzyme-free amplification power of the HCR, the inherent high sensitivity of the electrochemical technique, and label-free detection which utilizes an electroactive species as a signaling molecule that binds to the anionic phosphate backbone of DNA strands via electrostatic force, not only does the proposed strategy enable sensitive detection of GSH, but show high selectivity against other amino acid, making our method a simple and sensitive addition to the amplified GSH detection. [ABSTRACT FROM AUTHOR]

A new continuous process for preparing methanol–diesel oil emulsified fuel is proposed using an impinging stream–rotating packed bed. The combustion of methanol–diesel oil emulsified fuel is significantly affected by its stability. Thus, the stabilization of the methanol–diesel oil emulsified fuel was investigated by varying numerous factors, including high-gravity factor, impinging distance, hydrophilic-lipophilic balance value, liquid flow rate, co-surfactants, content of methanol and emulsifier, and so on. The stabilized time and size of dispersed phase of methanol-diesel oil emulsified fuel were 762 h and 12 μm separately at the operating conditions of liquid flow rate of 70 L/h, an impinging distance of 30 mm, a hydrophilic–lipophilic balance value of 5.4, a high gravity factor of 208.1, a methanol volume content of 15%, co-surfactants of 1-butanol, an emulsifier amount of 3%, and consecutive recycle time of 3. The proposed technology can be applied in industries because of the use of relatively less emulsifier as well as its continuity, processing efficiency, and ease of application in large-scale production. [ABSTRACT FROM AUTHOR]

In this work, a simple and sensitive electrochemical strategy for arsenite detection based on the ability of arsenite bound to single-strand DNA (ssDNA) and the signal transduction of single wall carbon nanotubes (SWCNTs) is developed. To realize this purpose, the ssDNA/SWCNTs complexes were formed at first by making ssDNA wrapped around SWCNTs via π-stacking. In the presence of arsenite, the arsenite could strongly bind with the G/T bases of ssDNA and decrease the π–π interaction between ssDNA and SWCNTs, resulting in a certain amount of ssDNA dissociating from the complexes. The separated SWCNTs were selectively assembled on the self-assembled monolayer (SAM) modified Au electrode. Then the SWCNTs onto the SAM-modified Au electrode substantially restored heterogeneous electron transfer that was almost totally blocked by the SAM. The assembled SWCNTs could generate a considerably sensitive and specific tactic for signal transduction, which was related to the concentration of the arsenite. Through detecting the currents mediated by SWCNTs, a linear response to concentration of arsenite ranging from 0.5 to 10 ppb and a detection limit of 0.5 ppb was readily achieved with desirable specificity and sensitivity. Such a SWCNTs-based biosensor creates a simple, sensitive, nonradioactive route for detection of arsenite. In addition, this demonstration provides a new approach to fabrication of stable biosensors with favorable electrochemical properties believed to be appealing to electroanalytical applications. [ABSTRACT FROM AUTHOR]

In this work, we synthesized a type of magnetic mesoporous silica nanoparticle (denoted as Fe 3 O 4 @MSN) with Fe 3 O 4 as the core and mesoporous silica the shell. The superparamagnetic Fe 3 O 4 -core provides high peroxidase-mimic activity and makes the artificial enzymatic system easily recyclable. Furthermore, Fe 3 O 4 nanoparticles are encapsulated in MSN shells to hinder the aggregation and keep them stable even under harsh conditions. Meanwhile, small active molecules are allowed to diffuse in and out of the MSN shells. Based on these functional units, the Fe 3 O 4 @MSN as robust nanoreactors can catalyze a self-organized cascade reaction, which includes oxidation of glucose by oxygen to yield gluconic acid and H 2 O 2 , and the latter further oxidizes 3,3,5,5-tetramethylbenzidine (TMB) to produce a color change. The Fe 3 O 4 @MSN, whose catalytic efficiency was not strongly dependent on pH and temperature, was successfully used for the detection of glucose and showed excellent sensitivity with a detection limit of 0.4×10 −5 mol/L. Nevertheless, the assay is also highly selective toward the glucose detection. [ABSTRACT FROM AUTHOR]

Abstract: Sedimentary environment and formation mechanism of the mud deposit in the central South Yellow Sea of China during the last 40kyr are studied based on the analysis of particle size, sediment density, chemical features, magnetic properties and AMS 14C ages of a new core YS01A together with other available core data. The results show that there exist four sedimentary sections during this 40kyr period, including two marine sections (A and C) and two terrestrial/intertidal sections (B and D). Sedimentary indexes of section D, which were formed before 40kyr, show that strong weathering and erosion occurred in this section. In contrast, sedimentary environment of section B was wetter and warmer and weathering and erosion were not as strong as in section D. Marine deposits in both sections A and C indicated the effects of sea level rise and section C was deposited when the climate was much wetter than in section A. Variations of climate and local hydrodynamics created different sediment features of two marine sections. From the estimated river discharges of the Huanghe, Changjiang and relevant Korean rivers and calculation of mud deposit volumes of section A during the past 9.7kyr, it is found that the sediment inputs from these river sources can only account for about 48% of sediments in the two mud deposits of the central and southeastern South Yellow Sea. The other main source of sediments is identified to be the seabed erosion, resuspension and redeposition from the Yellow Sea and, to a lesser extent, from the biogenesis and diagenesis. It provides a unique opportunity of understanding the formation and source of mud deposits by comparing the sedimentary properties of sections A and C in core YS01A. It is found that formation of mud deposits is not related directly to the Yellow Sea Warm Current, which only changed the sediment properties of mud deposits in section A since it formed from Holocene by bringing a large amount of organic mass and finer particles. However, cold water mass developed in this area is important as it helped to trap more and finer particles in the two marine sections. Upwelling usually occurs around 50m bathymetry which is at the juncture of two opposite water currents and has induced the thickest sediment layer. This study also confirmed that formation of the mud deposit in the central South Yellow Sea is caused mainly by the tidal currents on the continental shelves. [Copyright &y& Elsevier]

Abstract: A novel effective medium theory was proposed to model the thermal conductivity of porous materials. In this theory, phases (or components) are treated as small spheres dispersing into an assumed uniform medium with the thermal conductivity km . A simple algebraic expression for the thermal conductivity based on this theory was derived, in which each has a distinct physical basis. The expression can unify five basic structural models (Series, Parallel, two forms of Maxwell–Eucken, effective medium theory) through variations of km . Furthermore, the feasibility of the model was evaluated using the experimental data from previous literatures and those calculated by this model. [Copyright &y& Elsevier]

Abstract: The thermal conductivity of highly porous mullite materials (from 72 to 86vol% porosity) has been measured by the transient plane source (TPS) technique at room temperature. These materials were fabricated by foaming and starch consolidation and showed similar microstructures with different porosities. From the point of view of heat conduction, these materials can be considered as a two-phase system, viz. a dense mullite skeleton and air, and their thermal conductivities describe heat transfer through these composite materials. Through comparing experimental data and predicted values derived from theoretical models, these materials can be classified as “internal porosity” materials and their thermal conductivities are bounded between the Maxwell–Eucken 1 model and the effective medium theory (EMT) equation. Then the porosity dependence of thermal conductivity was modeled by a simple model which assumes that components were contained in a uniform medium with thermal conductivity km . [Copyright &y& Elsevier]

Abstract: Regional composite pollution and variation of atmospheric oxidizing ability are significant problems in Beijing and its surrounding areas. In particular, a southwest–northeast prevailing wind makes nonlinear variation of ozone and its precursors complex. In this study, simultaneous measurements of surface ozone (O3), nitric oxide (NO), nitrogen dioxide (NO2), nitrogen oxide (NOx) and carbon monoxide (CO) were carried out from August 2009 to June 2010 to investigate ozone level and precursor concentrations in Northern China. Gucheng (GC), Longtanhu (LTH) and Xinglong (XL) were selected to represent rural area, urban area and background area in North China Plain, respectively. The results showed that there were two peaks for primary pollutants (NOx and CO) at urban and rural areas, and the highest values appeared nearly on rush hours. There was a single peak for O3 and Ox with peak values appearing at afternoon. The primary pollutants at urban and rural areas were higher than those in background region. However, the concentration of secondary pollutant O3 at downwind background areas was much higher than other sites due to transportation. Diurnal variations of pollutants indicated that O3 and Ox had peak values at afternoon, while other primary pollutants showed two peak values nearly on rush hours. Furthermore, high concentrations of O3 and Ox at background site XL also implied a robust atmospheric oxidizing ability. A positive correlation was observed between CO and O3 at XL site, which implied that air masses to the site had a large loading of anthropogenic emission experiencing strong photochemical processing. The correlation between CO and O3 was negative at GC and LTH, which indicated that local emission of precursors had significant influence on the formation of ozone. There was a positive correlation between NOx and Ox at GC and XL, which implied that NOx contributed to the formation of ozone, while a negative correlation meant titration in urban site LTH neutralized the formation of ozone due to high level of NO. [Copyright &y& Elsevier]

Highlights: [•] The penalized histogram difference criterion, PHDC, to determine the number of clusters of finite mixture models. [•] The PHDC guarantees a minimum at optimal number of clusters. [•] The utility of the PHDC is evaluated with respect to other criteria, such as HDC, AIC, MML, ICOMP, and EDC. [Copyright &y& Elsevier]

[Display omitted] • The SPEEK/NaY mixed matrix membranes were prepared for CO 2 /N 2 separation. • The string-like nanochannels for facilitating CO 2 transport in MMMs were formed. • NaY zeolite was uniformly dispersed in SPEEK matrix due to good compatibility between two phases. • Improved CO 2 permeability and CO 2 /N 2 selectivity of MMM were simultaneously obtained due to selective surface flow effect. Mixed-matrix membranes (MMMs) have aroused great attention for CO 2 capture due to high gas separation properties and good processability. However, besides high cost, poor interfacial compatibility and inorganic particles aggregation in MMMs hinder their further development. Herein, we chose microporous sodium zeolite-Y (NaY) as a filler, which was added into sulfonated poly (ether ether ketone) (SPEEK) to engineer the MMMs for CO 2 /N 2 separation. We deeply studied the influence of NaY incorporation on microstructure and separation properties of the membrane. It is obvious that NaY particles were evenly distributed in the SPEEK matrix due to strong interfacial interaction by hydrogen bonding, which was verified by ATR-FTIR and SEM results, and the string-like nanochannels were formed from the SAXS observation. MMM incorporated with 20 wt% NaY exhibited the separation properties (CO 2 permeability of 765 Barrer; CO 2 /N 2 selectivity of 63) at 1 bar under the pure gas conditions, which were superior to the pristine SPEEK membrane as well as the MMMs incorporated with other zeolites, transcending the 2008 Robeson's upper bound. The enhancement in separation properties is due to the fact that CO 2 molecules preferentially pass through the string-like nanochannels faster than N 2 molecules under elevated relative humidity owing to selective surface flow effect. Moreover, an increase in total water of MMMs loaded with NaY also contributed to enhanced CO 2 permeability, while improved CO 2 /N 2 selectivity resulted from high bound water. More importantly, stability studies reveal that the MMM (with 20 wt% NaY loading) held outstanding CO 2 separation properties for over 360 h, demonstrating outstanding stability under a gas mixture testing condition. [ABSTRACT FROM AUTHOR]

Abstract: We report here a highly sensitive and label-free electrochemical aptasensing technology for detection of interferon-gamma (IFN-γ) based on graphene controlled assembly and enzyme cleavage-assisted target recycling amplification strategy. In this work, in the absence of IFN-γ, the graphene could not be assembled onto the 16-mercaptohexadecanoic acid (MHA) modified gold electrode because the IFN-γ binding aptamer was strongly adsorbed on the graphene due to the strong π–π interaction. Thus the electronic transmission was blocked (eT OFF). However, the presence of target IFN-γ and DNase I led to desorption of aptamer from the graphene surface and further cleavage of the aptamer, thereby releasing the IFN-γ. The released IFN-γ could then re-attack other aptamers on the graphene, resulting in the successive release of the aptamers from the graphene. At the same time, the “naked” graphene could be assembled onto the MHA modified gold electrode with hydrophobic interaction and π-conjunction, mediating the electron transfer between the electrode and the electroactive indicator. Then, measurable electrochemical signals were generated (eT ON), which was related to the concentration of the IFN-γ. By taking advantages of graphene and enzyme cleavage-assisted target recycling amplification, the developed label-free electrochemical aptasensing technology showed a linear response to concentration of IFN-γ range from 0.1 to 0.7pM. The detection limit of IFN-γ was determined to be 0.065pM. Moreover, this aptasensor shows good selectivity toward the target in the presence of other relevant proteins. Our strategy thus opens new opportunities for label-free and amplified detection of other kinds of proteins. [Copyright &y& Elsevier]

Abstract: A sensitive label-free “signal-on” electrochemical approach for detection of methyltransferases (MTase) activity is developed based on the signal transduction and amplification of single wall carbon nanotubes (SWCNTs). In this method, the oligonucleotide I is first self-assembled on the electrode via Au–S bonding. After hybridization with its complement ssDNA (oligonucleotide II), duplex strand DNA (dsDNA) probes containing specific recognition sequence of Dam MTase and methylation-sensitive restriction endonuclease Dpn I is then formed on the electrode. In the presence of Dam MTase and Dpn I, the dsDNA probes are methylated and subsequently cleaved into two dsDNA fragments. After heating, the remained dsDNA fragments on the electrode melted into ssDNA fragments. Then the SWCNTs can be controllably assembled on the ssDNA fragments remained on the electrode, mediating efficient electron transfer between the electrode and electroactive species. It generates measurable current signal (eT ON), which is related to the concentration of the Dam MTase. The resulting change in electron transfer efficiency is readily measured by differential pulse voltammetry at Dam MTase concentrations as low as 0.04U/mL. This method does not need electroactive molecules labeling on the methylation-responsive DNA probes. The linear response of the developed facile signal-on electrochemical sensing system for Dam MTase is in the range of 0.1–1.0U/mL. In addition, such a SWCNTs based electrochemical assay also has the ability to screen inhibitors for Dam MTase. [Copyright &y& Elsevier]

Abstract: The 165 year morphological evolution of the Changjiang (Yangtze) Estuary and its long-term equilibrium characteristics have been investigated using 16 selected maritime charts from 1842 to 2006. These charts were digitized and analyzed with a GIS to provide quantitative estimates of geomorphologic changes below selected bottom elevations. The results show that the Changjiang Estuary has experienced overall erosion over this 165 year period, having been affected by several large erosion and deposition episodes. It is found that the overall volume changes are less than 10% and aspect ratios of <5 have increased from 2% to ca. 30%. During this period, both coastlines and thalwegs have become straighter and more aligned with the propagation direction of offshore tidal current, indicating that the estuary is approaching dynamic equilibrium. Based on variations of aspect ratios and thalweg movements, five types of stable channels were identified. Significant topographical changes, including infilling after 1958 and erosion after 1980, are principally associated with engineering work around the estuary and a reduction in sediment supply. Although human influence only notably occurred at certain locations in the estuary, such as upstream node of an estuary, it had a significant impact on the overall geomorphologic evolution. In addition to these anthropogenic effects, freshwater flow, sediment discharges, tide propagation and Coriolis force are also found to play important roles in channel development within the estuary. By contrast, changes in other factors such as sea level changes and wave climate were considered to be of relatively minor importance in the morphological evolution process of the estuary. [Copyright &y& Elsevier]

Abstract: Nowadays, β2-agonists are abused illegally as “lean meat agents” for food-producing animals, and cause increasing food-safety accidents in some countries. Due to their hazard to the human health, “lean meat agents” are banned in most countries and required to be routinely monitored. We herein report a disposable electrochemiluminescent immunosensors array for near-simultaneous assay of multiple β2-agonist residues in swine urine, by using ractopamine and salbutamol as the models. In this investigation, a screen-printed carbon electrodes array was assembled and acted as the substrate of the immunosensors array. Then the immunosensors array was constructed by site-selectively immobilizing the antigens of ractopamine and salbutamol on the working electrodes of array. After the competitive immuno-binding, with the aid of a homemade single-pore-four-throw switch, the electrochemiluminescent signals of the two β2-agonists were sequentially detected using a non-array detector. The limits of detection for ractopamine and salbutamol were 8.5 and 17pg/mL, respectively, which were much lower than those of the most previous reports. Compared with other routine methods based on chromatography and ELISA, this method is more suitable for screening of multiple β2-agonists in quantities of samples, owing to its merits of low cost, user-friendliness and high throughput, and shows great promise in food safety and agonist surveillance. [Copyright &y& Elsevier]

Abstract: As a familiar β2-agonist, clenbuterol (CLB) was frequently reported to be illegally abused as a “lean meat agent” for livestock breeding, since it could improve growth rate and inhibit fat synthesis. Due to its potential hazard to human health, it has been forbidden as growth promoter for food-producing animal feeding in most countries. Therefore, the routine monitoring of CLB abuse is exceedingly necessary for food safety purpose. We herein report an ultrasensitive electrochemiluminescent immunosensor, which is firstly applied for assay of trace amount of CLB residue in swine urine. In this investigation, gold nanoparticles doped chitosan composite film was utilized for antigen immobilization, and Ru(bpy)3 2+-labeled antibody was utilized as the tracer antibody. With a competitive immunoassay format, good analytical performance was obtained. The proposed method shows a linear range of 0.010–1.0ng/mL, with a limit of detection of 0.0050ng/mL for CLB, which is evidently lower than that of most previous reports. This method is suitable for screening of trace amount of CLB residue, due to its simple manipulation, short assay time, and high detection sensitivity, and exhibits great promise in food safety and agonist monitoring. [Copyright &y& Elsevier]

Abstract: We report here a highly sensitive electrochemical sensing platform for Ag+ detection based on Ag+-induced conformational change of cytosine-rich single stranded DNA C-rich ssDNA probe and the controlled assembly of MWCNTs. In the protocol, the gold electrode was first modified with a dense 16-mercaptohexadecanoic acid self-assembled monolayer (MHA/SAM). The hydrophobic MHA/SAM isolated the electrode from the electroactive indicator in the aqueous solution, which resulted in the electronic transmission blocking. It was eT OFF state. In the presence of Ag+, C–Ag+–C coordination induced the conformational change of C-rich ssDNA probe from random-coil structure to fold into a hairpin structure, which cannot wrap on the surface of the MWCNTs. Then the “naked” MWCNTs can be assembled on the MHA/SAM gold electrode, mediating the electron transfer between the electrode and the electroactive indicator. It generated measurable electrochemical signals (eT ON). The resulting change in electron transfer efficiency was readily measured by differential pulse voltammetry at target Ag+ concentrations as low as 1.3nM. The linear response range for Ag+ detection was from 10 to 500nM. This method dose not need of electroactive molecules labeling on the C-rich ssDNA probe. Moreover, it has good selectivity to other environmentally relevant metal ions. Therefore, the developed electrochemical assay is an ideal method for Ag+ detection with some advantages including sensitivity, selectivity, simplicity, low-cost, and no requirement for probe label preparation. We expect that this strategy could be a generalized platform for DNA-based sensing. [Copyright &y& Elsevier]

Abstract: A novel electrochemical strategy for monitoring the activity and inhibition of T4 polynucleotide kinase (PNK) is developed by use of titanium ion (Ti4+) mediated signal transition coupled with signal amplification of single wall carbon nanotubes (SWCNTs). In this method, a DNA containing 5′-hydroxyl group is self-assembled onto the gold electrode and used as substrate for PNK. The biofunctionalized SWCNTs with anchor DNA and ferrocene are chosen as the signal indicator by virtue of the intrinsic 5′-phosphate end of anchor DNA and the high loading of ferrocene for electrochemical signal generation and amplification. The 5′-hydroxyl group of the substrate DNA on the electrode is phosphorylated by T4 PNK in the presence of ATP, and the resulting 5′-phosphoryl end product can be linked with the signal indicator by Ti4+. The redox ferrocene group on the SWCNTs is grafted to the electrode and generates the electrochemical signal, the intensity of which is proportional to the activity of T4 PNK. This assay can measure activity of T4 PNK down to 0.01UmL−1. The developed method is a potentially useful tool in researching the interactions between proteins and nucleic acids and provides a diversified platform for a kinase activity assay. [Copyright &y& Elsevier]