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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]

In the traditional microfield speckle pattern interference measurement system, due to the use of high-magnification objective lens, the working distance is small and the shearing device cannot be introduced to implement shearography measurement. Thus the distribution of the deformation gradient on a microstructure surface cannot be measured. A system for the synchronous measurement of the surface deformation and gradient distribution of a microstructure was designed. Through the combination of focusing lens, convex lens, and low-magnification objective lens, the microstructure surface was clearly magnified and the internal distance of the system was enlarged. Thus the shearing device can be introduced to realize the shearography measurement under the microfield view. The synchronous full-field measurement of the structural surface deformation and its gradient distribution was further realized by the introduction of a reference light and designing of an optical path switch. In addition, the designed system had a zoom feature, which can facilitate the measurement in variable field of view in a certain range. The feasibility of the system was verified by theoretical analysis and experiment, and the practicability was validated by testing the chip and circuit board. [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]

Objective. To observe the effects of empirical prescriptions of traditional Chinese medicine (TCM) on inflammatory mediators in pediatric asthma and to explore the underlying molecular mechanism in the treatment of asthma. Methods. A total of 182 children with asthma were randomly placed into either the TCM group (n=97) or the salbutamol and montelukast (SM) group (n=85). Patients in the TCM group were treated with a series of empirical prescriptions of TCM, while those in the SM group received salbutamol and montelukast. Both groups received their respective treatment for 12 weeks. There were 35 patients in TCM group and 34 patients in SM group providing venous blood. Real-time PCR was used to determine the mRNA expression levels of interleukin- (IL-) 10, IL-17, matrix metalloproteinase-9 (MMP-9), and transforming growth factor β1 (TGF-β1) in peripheral blood mononuclear cells before and after treatment. Enzyme-linked immunosorbent assay was used to measure the levels of IL-10, IL-17, MMP-9, and TGF-β1 in peripheral blood before and after treatment. Results. The mRNA expression of TGF-β1 in the SM group was downregulated (P=0.00) after treatment. No significant differences were found between the TCM group and the SM group after treatment (P>0.05). In the TCM group, the levels of IL-10, IL-17, and MMP-9 significantly decreased after treatment (P=0.01, 0.04, and 0.03, resp.). In the SM group, IL-17, MMP-9, and TGF-β1 levels significantly decreased after treatment (P=0.00, 0.03, and 0.00, resp.). There was no significant difference between the two groups regarding the levels of IL-10, IL-17, TGF-β1, and MMP-9 (P>0.05). The difference of the level of IL-17 was negatively correlated with the change of C-ACT score in TCM group and SM group. Conclusion. TCM has a regulatory effect on the balance of some inflammatory mediators in pediatric asthma. [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]

This study investigated cell physiological and metabolic responses of Lactobacillus paracasei to osmotic stresses. Both cellular fatty acid composition and metabolite profiling were responded by increasing unsaturated and epoxy-fatty acid proportions, as well as accumulating some specific intracellular metabolites. Simultaneously, metabolite profiling was adopted to rationally and systematically discover potential osmoprotectants. Consequently, exogenous addition of proline or aspartate was validated to be a feasible and efficacious approach to improve cell growth under hyperosmotic stress in shake flasks. Particularly, with 5-L cultivation system, l-lactic acid concentration increased from 108 to 150 g/L during the following 16-h fermentation in 2 g/L proline addition group, while it only increased from 110 to 140 g/L in no proline addition group. Moreover, glucose consumption rate with proline addition reached 3.49 g/L/h during this phase, 35.8 % higher than that with no proline addition. However, extreme high osmotic pressure would significantly limit the osmoprotection of proline, and the osmolality threshold for L. paracasei was approximately 3600 mOsm/kg. It was suggested that proline principally played a role as a compatible solute accumulated in the cell for hyperosmotic preservation. The strategies of exploiting osmotic protectant with metabolite profiling and enhancing l-lactic acid production by osmoprotectant addition would be potential to provide a new insight for other microorganisms and organic acids production. [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]

Sulfonated carbon nanotubes (sCNTs) were prepared by reacting concentrated sulfuric acid with carbon nanotubes (CNTs) on the defect sites. Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM) were used to characterize the morphology and structure of sCNTs, respectively. Subsequently, polyaniline (PANI)/nickel hexacyanoferrate (NiHCF)/sCNT interconnected composite films were electrodeposited on the platinum electrode by the one-step co-polymerization using cyclic voltammetry in an aqueous dispersion containing sCNTs. The effect of concentration of NiSO and KFe(CN) in the prepared solution on the morphology and structure of PANI/NiHCF/sCNTs composite films was studied by scanning electron microscopy (SEM), FTIR spectroscopy, and X-ray diffraction (XRD), respectively. The effect of concentration of NiSO and KFe(CN) in the prepared solution on polymerization and electrochemical performance was investigated by cyclic voltammetry (CV), galvanostatic charge/discharge tests, and electrochemical impedance spectroscopy (EIS). One-step electrodeposition mechanism was discussed deeply. It was found that sulfonic acid groups had been attached to surface of CNTs, and sCNTs had higher dispersibility than CNTs in an aqueous dispersion. The morphology of PANI/NiHCF/sCNTs interconnected composite films was remarkably influenced by the concentration of NiSO and KFe(CN). The tubular packing structure appeared with the low concentration of NiSO and KFe(CN) in prepared solution, while the beautiful coral-like interconnected structure exhibited with 0.04 mol L NiSO and 0.04 mol L KFe(CN), which was mainly attributed to the π-π* electron stacking effect among sCNTs, NiHCF, and PANI. The specific capacitance and electroactivity of PANI/NiHCF/sCNTs composite films increased markedly with the increase of concentration of NiSO and KFe(CN) in prepared solution. The specific capacitance of PANI/NiHCF/sCNTs composite film was 430.77 F g with 0.04 mol L NiSO and 0.04 mol L KFe(CN) due to self-doping effect of sCNT in composite films. The cycle stability of PANI/NiHCF/sCNTs composite films was enhanced with the increase of NiSO and KFe(CN) in prepared solution. [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 the practical application of speckle pattern interferometry, it is often necessary to measure the deformation or defect of some specimens placed in boxes. Transparent glass observation windows are often used on one side of these boxes. In laser speckle pattern interferometry, the glass windows often cause local overexposure in the field of view, which has a great influence on the measurement. A method for identification and elimination of overexposed areas based on polarized optics is proposed. A polarization camera is used for image acquisition; polaroid is used to filter out stray and chaotic interference light, greatly reducing the overexposed area in the imaging field of view, and then feature extraction technology is used to identify and extract the overexposed area caused by the glass window. Finally, according to the measurement information around the overexposed area, the phase of the overexposed area is fitted and corrected, so as to obtain the speckle pattern interferometry measurement results without overexposed points. Experimental results show that the proposed method can effectively extract and eliminate the overexposed area, and good measurement results can be obtained. [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]

Formation and preservation of greigite can indicate the physicochemical characteristics of sedimentary environment. Presence of greigite can be diagnosed in the late Pleistocene fluvio-lacustrine sedimentary layers of 29.4-29.7 and 26.1-27.1 m in core ZK30 of the Yellow River delta, based on analysis of particle size, magnetic properties, scanning electron microscope (SEM) and X-ray diffraction (XRD) measurements. These layers are the transition zones from shallow marine facies to fluvio-lacustrine facies, and from fluvio-lacustrine facies to salt marsh facies in an ascending order, respectively. They are characterized by higher SIRM and SIRM/ χ (>30 kA m) values than those of other layers, suggesting the possible existence of greigite. Both SEM and XRD analyses confirm its presence. However, sediment layer of 29.4-29.7 m are coarser, and greigite coexists with pyrite, but sediment layer of 26.1-27.1 m are finer and the occurrence of greigite is not accompanied by pyrite. The different occurrence of greigite in the two layers suggests that different climate condition and sedimentary environment control its formation and preservation. [ABSTRACT FROM AUTHOR]

To explore the dependences of morphology and electrochemical performance of polyaniline/nickel hexacyanoferrate (PANI/NiHCF) nanogranules on pH value of the reaction system, electrodeposition of PANI/NiHCF nanogranules was performed across a pH range from 0 to 7 on carbon nanotubes (CNTs)-modified platinum substrate by cyclic voltammetry in a mixture of 0.002 mol L NiSO, 0.25 mol L NaSO, 0.002 mol L KFe(CN), and 0.01 mol L aniline solutions. The morphology and structure of PANI/NiHCF nanogranules were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy, respectively. The supercapacitive performances of the nanogranules were investigated with cyclic voltammetry (CV), charge/discharge tests, and electrochemical impedance spectroscopy (EIS). The results showed that the nanogranules with different morphology and sizes were obtained with the change of pH values from 0 to 7, which could control the mechanism of homogeneous or heterogeneous nucleation directly. The nanogranules were dispersed in matrix uniformly at pH 0 and pH 1, while the size of which decreased with the increase of pH values. The smooth cross-linking network structure was found from pH 2 to 7. The structure of PANI/NiHCF nanogranules had slightly changed from pH 0 to 7. PANI/NiHCF nanogranules had good electrochemical performance from pH 0 to 7 in a mixture of 0.5 mol L HSO and 0.5 mol L KNO solutions, and the highest specific capacitance value of 274 F g was obtained at current densities of 2 mA cm in neutral medium. PANI/NiHCF nanogranules had high stability in neutral medium after 2,000 cycles by CV. [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]

A novel polymeric antioxidant, hydroxyl-terminated polybutadiene-bound 2,2-thiobis(4-methyl-6-tert-butylphenol) (HTPB-IPDI-TPH), was prepared by binding 2, 2-thiobis(4-methyl-6-tert-butylphenol) (TPH) onto hydroxyl-terminated polybutadiene (HTPB) with isophorone diisocyanate (IPDI). Fourier-transform infrared spectroscopy (FTIR), 13C nuclear magnetic resonance spectroscopy (13C NMR), and gel permeation chromatography (GPC) were used to characterize the structure of HTPB-IPDI-TPH. The thermal stability of HTPB-IPDI-TPH was studied by thermogravimetry analysis (TGA). The effect of HTPB-IPDI-TPH on thermo-oxidative aging resistance of NR vulcanizates was investigated, and the mechanism of thermo-oxidative aging resistance was preliminarily discussed. The results showed that HTPB-IPDI-TPH contributed better thermal stability and thermo-oxidative aging resistance to NR vulcanizates than TPH. The thermo-oxidative aging resistance of HTPB-IPDI-TPH was more remarkable in the later stage of aging. Attenuated total-reflectance Fourier-transform infrared spectroscopy (FTIR-ATR) analysis showed that the relative content of carbonyl groups of NR vulcanizate with HTPB-IPDI-TPH was obviously lower than that with TPH after thermo-oxidative aging. It is suggested that ‒NHCOO‒ groups in HTPB-IPDI-TPH enhanced the ability of trapping alkyl peroxide radicals. [ABSTRACT FROM PUBLISHER]

A novel polymeric antioxidant HTPB-IPDI-TPH was synthesized by the reaction between 2,2-thiobis (4-methyl-6-tert-butylphenol) (TPH) and an adduct (HTPB-IPDI) from hydroxyl terminated polybutadiene (HTPB) and isophorone diisocyanate (IPDI). The effects of raw materials ratio and the reaction condition were investigated by measuring the content of the residual –NCO groups of the reactants during the reaction. The structure of HTPB-IPDI-TPH was characterized by FTIR and 1H NMR. Thermo-oxidative aging resistance of HTPB-IPDI-TPH was evaluated by oxidation induction time (OIT) from DSC of natural rubber vulcanizates. The optimal reaction conditions between IPDI and HTPB were that the amount of dibutyltin dilaurate (DBTDL) was 0.6 wt% based on IPDI, and the temperature and time were 40°C and 270 min, respectively. The reaction conditions between TPH and HTPB-IPDI were that the molar ratio of TPH to –NCO in HTPB-IPDI was 3:1, and the amount of DBTDL was 1.6 wt% based on the total of reactants, and the temperature and time were 75°C and 360 min, respectively. Thermo-oxidative aging resistance of HTPB-IPDI-TPH was obviously superior to the corresponding low molecular counterpart (TPH) for natural rubber vulcanizates. [ABSTRACT FROM AUTHOR]

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]

Abstract: A sensitive and specific electrochemical assay for detection of thrombin based on aptamer and ferrocenylhexanethiol loaded silica nanocapsules (FcSH/SiNCs) amplification is described. In the protocol, a double aptamer sandwich structure was formed in the presence of thrombin, in which an aptamer-labeled FcSH/SiNCs for electrochemical detection, and a streptavidin-coated magnetic bead immobilized aptamer for rapid and specific separation of target protein. After separated from the sample mixture under a magnetic field, the sandwich complex was treated with NaOH to release the loaded ferrocenylhexanethiol (FcSH) from the silica nanocapsules (SiNCs). Differential pulse voltammetry (DPV) was employed to detect the released FcSH, which was related to the concentration of the thrombin. The method took advantage of sandwich binding of two affinity aptamers for increased specificity, high payload of FcSH in SiNCs for signal amplification, magnetic beads for fast magnetic separation. The peak current of released FcSH had a good linear relationship with the thrombin concentration in the range of 0.1–5nmol/L, and the detection limit of thrombin in the method was 0.06nmol/L. The detection was also specific for thrombin without being affected by other proteins, such as immunoglobulin G, bovine serum albumin, lysozyme and human serum albumin. The method has been used to detect thrombin in human serum albumin with minimum background interference. [Copyright &y& Elsevier]

Rice branching, including the formation of tillers and panicle branches, has been well investigated over the past several years because of its agronomic importance. A major breakthrough in elucidating rice tillering in the recent years was the discovery of strigolactones, a specific group of terpenoid lactones that can inhibit axillary bud outgrowth. Since that discovery, new tillering mutants, that is, dwarf 27 (d27) or dwarf14 (d14, also reported as d88 or htd2), have been identified with reduced strigolactone levels or strigolactone response. DWARF27 (D27) and DWARF14 (D14) probably act on strigolactone biosynthesis and signal transduction, respectively. Additionally, several genes controlling panicle branches have been identified recently. DEP1 and IPA1/WFP are essential dominant/semidominant regulators that determine rice panicle branches and thus affect the grain yields. More importantly, dep1 and ipa1 alleles have been shown to be applicable for the improvement of rice grain yields in molecular breeding. [ABSTRACT FROM AUTHOR]

Abstract: The effects of light/dark cycle, mixing pattern and partial pressure of H2 on the growth and hydrogen production of Rhodobacter sphaeroides ZX-5 were investigated. The results from light/dark cycle culture showed that little or no hydrogen production was observed during the dark periods, and the hydrogen production immediately recovered once illumination was resumed. Also, it was found that the optimum condition of shaking velocity was 120rpm for hydrogen photo-fermentation. Meanwhile, shaking during H2 production phase (i.e., cell growth stationary phase) of photo-fermentation played a crucial role on effectively enhancing the phototrophic hydrogen production, rather than that during cell exponential growth phase. The other factor evaluated was hydrogen partial pressure in the culture system. The substrate conversion efficiency increased from 86.07% to 95.56% along with the decrease of the total pressure in the photobioreactor from 1.082×105 to 0.944×105 Pa, which indicated that reduction of H2 partial pressure by lowering the operating pressure substantially improved H2 production in an anaerobic, photo-fermentation process. [ABSTRACT FROM AUTHOR]

Abstract: Mud deposits are widespread in estuaries and on continental shelves, and contain important information regarding interactions between terrestrial and coastal processes. Magnetic properties of muddy sediments from the northeastern continental shelves of China, including shelves close to Korean coasts, were analyzed using bulk and size-fractionated samples to elucidate muddy sediment sources and transport. Types, concentration, and granulometry of magnetic minerals were determined and all samples were found to be dominated by magnetite. Muddy sediments from the Zhemin coast (off the Zhejiang and Fujian coasts) have the highest magnetic susceptibility (χ) and saturation isothermal remanent magnetization (SIRM) values, while those from the central and southeastern South Yellow Sea and the western Korea Strait have lower values reflecting lower magnetic mineral concentrations. Single domain ferrimagnetic grains dominate the magnetic particles in the central South Yellow Sea, while superparamagnetic (SP) grains contribute significantly to the magnetic grains in the Bohai Sea. SP and coarse multi-domain (MD) grains dominate magnetic grain assemblages in the North Yellow Sea and along the Zhemin Coast. Rock sediment particle size is not a major factor affecting the magnetic properties of the mud deposits in the study area. Rather, terrigenous inputs and hydrodynamic transport processes primarily control the magnetic properties, and sediments from the Changjiang and Huanghe rivers make the most significant contribution. This observation applies to the whole study area, although terrigeneous magnetic mineral concentrations decrease with increasing distance from the river mouths due to both sorting and mixing with other sediments with weak magnetic signatures. Bacterial magnetosomes also play a role in the central South Yellow Sea. [Copyright &y& Elsevier]

Abstract: A sensitive and selective ligase-based signal-on electrochemical sensing method for adenosine-5′-triphosphate (ATP) detection had been developed using molecular beacon (MB)-like DNA. In this method, the biotin-tagged MB-like DNA was self-assembled onto a gold electrode to form a stem-loop structure by means of facile gold-thiol chemistry, which resulted in blockage of electronic transmission. It was eT OFF state. In the presence of ATP, two nucleotide fragments which were complementary to the loop of the MB-like DNA could be ligated by the ATP-dependent T4 DNA ligase. Hybridization of the ligated DNA with the MB-like DNA induced a significant conformational change in this surface-confined DNA structure, which in turn released the biotin from the surface allowing free exchange of electrons with the electrode generating a measurable electrochemical signal (eT ON). The resulting change in electron transfer efficiency was readily measured by differential pulse voltammetry at target ATP concentrations as low as 0.05nM and with linear response range from 0.1 to 1000nM. Moreover, it was also able to discriminate ATP from its analogues. The proposed method had been successfully applied to the determination of ATP in the Escherichia coli O157:H7 extracts of water samples, and the linear response was found between the concentrations of 103 and 107 cfu/mL. [Copyright &y& Elsevier]

Abstract: The design, synthesis, characterization and application of biologically synthesized nanomaterials have become an important branch of nanotechnology. In this paper, we report the extracellular synthesis of gold nanoparticles using Barbated Skullcup (BS) herb (a dried whole plant of Scutellaria barbata D. Don) as the reducing agent. After exposing the gold ions to BS herb extract, rapid reduction of gold ions is observed leading to the formation of gold nanoparticles in solution. UV–vis spectrum of the aqueous medium containing gold nanoparticles showed a peak at around 540nm. Transmission electron microscopy (TEM) micrograph analysis of the gold nanoparticles indicated that they were well-dispersed and ranged in size 5–30nm. When the gold nanoparticles were modified on the glassy carbon electrode (GCE), it could enhance electronic transmission rate between the electrode and the p-nitrophenol. [Copyright &y& Elsevier]

Abstract: Provenance discrimination of marine sediments is an important topic in marine geology. Although the catchments of the Changjiang and Huanghe Rivers are regarded as the main sources of sediments on the shelves of the China Sea, identification of detailed sediment provenance is necessary for understanding sediment transport patterns and the paleoenvironment. Magnetic properties of both bulk sediment samples and different-sized particles from the Changjiang and Huanghe Estuaries are studied to discuss the origin of the sediments. The results show that the sediments are dominated by ferrimagnetic magnetite with a minor content of anti-ferromagnetic minerals such as hematite, and a higher concentration of ferrimagnetic minerals is observed for the Changjiang Estuary sediments. The crystal grains of ferrimagnetic minerals in the Changjiang Estuary are coarser than those in the Huanghe Estuary, whereas superparamagnetic grains significantly contribute to the Huanghe sediments. Magnetic parameters of χ SIRM, SOFT and χ ARM from different-sized particles present more obvious differences than these parameters from bulk particles, and S−100 and S−300 for both bulk samples and different-sized particles show distinct differences between the sediments from the two estuaries. Therefore the latter parameters are more useful to distinguish sediment origins. A comparison of the magnetic properties of sediments in these two estuaries with those on the shelves of the adjacent China Sea also suggests that the analysis of sediment magnetic properties is effective to identify sediment provenances. [Copyright &y& Elsevier]

Abstract: Bed features were mapped using a thermal depth recorder and a side-scan sonar in the Changjiang (Yangtze) Estuary, and flows were observed and bed surface materials were sampled to investigate bed material transport pathways. Distinct scales and dimensions of dunes were observed in terms of the classification scheme of Ashley [Ashley, G.M., 1990. Classification of large-scale sub-aqueous bedforms: A new look at an old problem. Journal of Sedimentary Research, 61, 160–172], forming a dune set in the flood season. Large dunes occurred predominately in the surveyed area of the estuarine zone, and two-dimensional dunes predominated in the dry season while three-dimensional dunes prevailed in the flood season. Sharp lee sides of dunes have low angles, indicating a significant suspended-load transport for the bedform migration, and the majority of them face down-estuary reflecting the controlling process by the ebb current. The bed material migrations in terms of relative maximum gross transport show a satisfactory agreement with the sonar mapping in the dry season. The relative maximum gross transport as an independent estimator of migration direction, can be used to effectively determine the bed material transport directions in the Changjiang Estuary. [Copyright &y& Elsevier]

[Display omitted] • ZIF-8-d-MK hybrid with the interlayer spaces was developed by coordinating ZIF-8 particles to amorphous MK sheets. • PVAm/ZIF-8-d-MK MMCMs for CO 2 /N 2 separation were successfully fabricated. • The interlayer spaces of ZIF-8-d-MK in the MMCMs function as CO 2 transport pathways. • The ZIF-8-d-MK hybrid was homogenously dispersed in PVAm matrix due to amorphous structure of MK sheets. Mixed-matrix composite membranes (MMCMs) have great potential in chemical separation process due to high performance, but the dispersibility of the filler is an enormous challenge we face. In this study, a ZIF-8-decorated metakaolin (ZIF-8-d-MK) hybrid was prepared by the AlO 4 tetrahedron oxygens in amorphous MK coordinating with the zinc ions of ZIF-8. MMCMs by coating polysulfone (PSf) ultrafiltration membranes with a mixture of hybrid and polyvinylamine (PVAm) were obtained, which can efficiently separate CO 2 from N 2. SEM and TEM results indicated that ZIF-8 particles were present between the amorphous MK sheets, and the coordination between the two phases was validated by FTIR. ZIF-8-d-MK, with a partially amorphous structure, exhibited homogeneous distribution in the PVAm matrix, as verified by SEM and XRD, and ZIF-8-d-MK had a strong interaction with the polymer matrix as certified by attenuated total reflectance-FTIR. A highest CO 2 permeance of 169 GPU with CO 2 /N 2 selectivity of 86.7 were acquired for MMCMs, loaded with 3 wt% ZIF-8-d-MK under pure gas conditions, which were much higher than those of MMCMs loaded with MK, ZIF-8, or a mixture of MK and ZIF-8. The improved values were primarily ascribed to the well-dispersed ZIF-8-d-MK serving as CO 2 transport pathways because of its molecular sieving effect for CO 2 /N 2. Importantly, under mixed gas feed conditions, the stability measurement demonstrated that the MMCMs adding 3 wt% ZIF-8-d-MK did long-term operation for over 360 h, and maintained great CO 2 separation performance. [ABSTRACT FROM AUTHOR]

Extraterrestrial particles have higher 3He/4He ratios than those of terrestrial sediments (> 100 Ra versus <0.03 Ra, where Ra is the 3He/4He ratio normalized to the atmospheric value of 1 .4×10-6). The inter-planetary dust particles (IDPs), which are very rich in 3He, continuously bombard the Earth and can accumulate in deposits. IDPs sedimentation rate changes can significantly influence 3He concentration in the Earth surface sediments. Since IDPs are not easy to detect in terrestrial deposits, measuring helium isotopes is a helpful approach to examine changes in IDPs. Helium concentration and helium isotopic composition magnetic substances and the quartz particles were examined for helium concentration and helium isotopic ratio. Results show that the 3He/4He ratio and the 3He concentrations of the magnetic substances are clearly higher than those of the bulk samples and the quartz particles, and, the 3He/4He ratio of the extracted magnetic substances is also higher than that of the average level of the Earth's crust. The higher helium content in the magnetic fractions can be explained by an influx of IDPs. [ABSTRACT FROM AUTHOR]

Abstract: Kluyveromyces marxianus NBRC1777 was identified as a thermotolerant yeast and was developed as a host for the expression of thermostable cellulase genes. The previously isolated genes for thermostable endo-β-1,4-glucanase, cellobiohydrolase, and β-glucosidase were introduced into the chromosome of K. marxianus and successfully expressed under the control of high-expression promoters. The recombinant K. marxianus expressing cellulase genes became able to grow in synthetic medium containing cellobiose or carboxymethyl-cellulose as the single carbon source. Moreover, the recombinant strain produced 43.4g/L ethanol from 10% cellobiose. These results suggest that K. marxianus may afford a useful host system, which may be applicable to the simultaneous saccharification and fermentation and the foundation of cellulose consolidated bioprocessing. [Copyright &y& Elsevier]

The solid‐phase microextraction technique (SPME) was used for the measurement of the partition coefficients of eight nitro polycyclic aromatic hydrocarbons (NPAHs) and ten polycyclic aromatic hydrocarbons (PAHs) between the polymeric coating of polydimethylsiloxane used in SPME and water (Ksw). The results demonstrate that the technique is simple, rapid, and reproducible, and thus provides a viable alternative to the conventional methods used for such measurements. There is a strong linear correlation between logKsw and the commonly used logKow (octanol–water partition coefficient) for PAHs, NPAHs, PCBs, and simple aromatics. The logKow values for NPAHs range from 2.78 to 4.75, and exhibit a general increase in value with increasing molecular weight. NPAHs are thus noticeably less hydrophobic than their parent PAHs counterparts, for which the log Kow values range from 3.35 to 5.20. [ABSTRACT FROM AUTHOR]

Plant architecture, referring here to the aerial part of a higher plant, is mainly determined by factors affecting shoot branching, plant height and inflorescence morphology. Significant progress has been made in isolating and characterizing genes that are directly involved in the formation of plant architecture, especially those controlling the initiation and outgrowth of axillary buds, elongation of stems and architecture of inflorescences. Most of these genes are conserved between dicotyledonous and monocotyledonous plants, indicating that these plants share similar regulatory pathways to establish their shape. The conservation of these genes makes them of great agronomical importance for improving crop yields. [Copyright &y& Elsevier]

China is the largest producer and consumer of rice in the world and a pioneer in applying hybrid rice technology. Although hybrid rice has contributed greatly to Chinese agriculture in the past decades, its potential to improve grain quality further is being questioned. However, to meet the challenges posed by severe crop damage by pests and diseases, the extensive use of pesticides and chemical fertilizers, and a shortage of water and energy, more elite rice cultivars are needed. In recent years, China has seen continued improvements in rice genetics, powered by functional genomics as a way forward to safeguard its rice production. Here, we briefly review the current status of rice breeding in China through strategies integrating hybrid rice technology, molecular marker-assisted breeding, functional genomics and genetically modified rice. [Copyright &y& Elsevier]

Prestressed high-strength concrete (PHC) pipe pile with static press-in method is widely used in recent years. The earth pressure at the pile-soil interface caused by the process of pile jacking has an important influence on the jacked pile construction and even the bearing characteristics. Based on a construction project in Dongying, the change law of earth pressure at pile-soil interface caused by the penetration of PHC pipe pile is analyzed by monitoring the earth pressure at pile-soil interface during pile jacking, and the evolution characteristics of earth pressure at pile-soil interface in viscous soil foundation are revealed. The results show that the earth pressure at the pile-soil interface at different positions (h/B) caused by the penetration of PHC pipe pile gradually increases with time. In the process of pile jacking, the influence of pile jacking on the earth pressure at the pile-soil interface on the pile body and part that exceeds the relative distance of effective pile end (h/B) is weak. In the process of pile jacking, the earth pressure at the pile-soil interface is greatly affected by the relative height of the pile end (h/B), so it is necessary to consider the effect of the pile length to calculate the earth pressure at the pile-soil interface. The phenomenon of "lateral pressure degradation" exists with the increase of h/B in the earth pressure at the pile-soil interface. The research results have certain engineering guiding significance for construction and bearing capacity determination of jacked pile in viscous soil foundation. • The change law of earth pressure caused by penetration of PHC pipe pile is analyzed. • The evolution characteristics of earth pressure at pile-soil interface in viscous soil foundation are revealed. • The research results have certain engineering guiding significance for construction and bearing capacity. [ABSTRACT FROM AUTHOR]

When the fracture is not developed and the connectivity is poor, the original single medium simulation cannot meet the accuracy requirements. Now, the seepage simulation of fractured rock mass has gradually developed from equivalent continuous medium to dual medium and multiple medium. However, it is still difficult to establish the connection between a discrete fracture network model and a continuous medium model, which makes it difficult to simulate the influence of fracture location on the seepage field of rock mass. As the excavation direction of the shaft is vertically downward, the surrounding strata are symmetrical around the plane of the shaft axis, which is different from the horizontal tunnel. Taking the auxiliary shaft of the No.1 Shaft in HighLiGongshan as the engineering background, combined with Monte Carlo methods and DFN generator built in FLAC3D5.01, a discrete fracture network is generated. Based on the dual medium theory, MIDAS is used to optimize the modeling of each fracture group. At the same time, the concept of "Fracture Weakening area" is introduced, and the simulation is carried out based on a fluid–solid coupling method. It is found that the simulation effect is close to the reality. The water inflow increases with the increase of shaft excavation depth, and the water inflow at the end of excavation is nearly three times larger than the initial value. Combined with Legendre equation, a new analytical formula of water inflow prediction is proposed. It is found that this analytical formula is more sensitive to permeability and has a greater safety reserve. [ABSTRACT FROM AUTHOR]

Background: Breastfeeding and maternal health play crucial roles in improving newborn health, which is closely related to the development of families and society. Early essential newborn care, which emphasizes early exclusive breastfeeding and skin-to-skin contact, is recommended by the World Health Organization. This study aimed to explore the association of early essential newborn care with breastfeeding and maternal outcomes.Methods: A nonrandomized controlled study was carried out from May 2020 to January 2021 in a tertiary hospital in Chengdu city, China. Pregnant women were recruited from the maternity ward before they gave birth. Early essential newborn care was performed for 91 mother-newborn pairs after birth in the intervention group, while routine birth care was performed for 91 mother-newborn pairs in the control group. Data on breastfeeding and maternal outcomes were collected pre-test and post-test and were recorded by trained data collectors and retrieved from hospital case record files.Results: Compared with the control group, the intervention group had a higher incidence of early breastfeeding initiation, an earlier initiation and longer duration for the first breastfeeding, a higher incidence of successful first breastfeeding, more exclusive breastfeeding at hospital discharge, higher maternal breastfeeding self-efficacy, a shorter duration of the third stage of labour, lower postpartum blood loss, and lower scores of maternal pain and anxiety postpartum; the differences were statistically significant (p < 0.05).Conclusion: The implementation of high-quality early essential newborn care can help mothers initiate early breastfeeding, improve exclusive breastfeeding rates at hospital discharge, enhance breastfeeding self-efficacy, promote the woman's recovery from labour, and reduce maternal anxiety and pain in the postpartum period. High-quality early essential newborn care is recommended to policymakers and medical professionals to improve breastfeeding and maternal outcomes.Trial Registration: Chinese Clinical Trial Registry, Retrospective Registration (27/7/2021), registration number: ChiCTR2100049231. [ABSTRACT FROM AUTHOR]

In this study, we developed an observation based photochemical box model with the measurement data collected at a suburban site (i.e., the Xianghe, XH site) of the Beijing-Tianjin-Hebei (BTH) region and the latest version of the Master Chemical Mechanism (MCM v3.3.1), which newly incorporated 498 reaction for the additional 155 species with the oxidation of isoprene by the OH radical. The influence of updated isoprene degradation on the radical budgets, formation of intermediate and secondary products by comparing the simulation results in the original version (MCM v3.2) was firstly analyzed to estimate whether the updates of precursors could influence the model performance on its evolution pathways and related products. The results demonstrated that though the input of isoprene could significantly decrease or increase the concentrations of OH and HO 2 radicals in the model simulation, respectively, the difference in the simulated concentrations of these radicals with isoprene oxidation before and after the updates was not statistically significant. For intermediate products, the simulated concentrations of formaldehyde and methacrolein (MACR) did not significantly alter before and after the updates, while the abundance of methyl vinyl ketone (MVK) reduced obviously (the maximum reduction of 31%) due to lower reaction coefficient between ISOPBO2 and NO and the lower branching ratios caused by the newly added pathways involving CISOPA and TISOPA in the updated scheme. On the other hand, the simulation concentrations of acrolein (ACR), glyoxal (Gly) and methylglyoxal (Mgly) increased significantly after the model updates. The dominant pathway for the increment of ACR was the decomposition of CH2CHCH2O produced by PE4E2CO, while those of Gly and Mgly were associated with radicals of C537O and PACLOOA that were both from the new intermediate radical of CISOPC. In addition, 39 isoprene oxidation products among the 155 new added species were identified to partition in the formation of secondary organic aerosol (SOA), which were coupled in the gas-particle partitioning module to optimize the formation of SOA, contributing 1.15 μg m−3 to the increase of SOA mean concentration. The updates of isoprene degradation further resulted in the significant change for its sensitivity in SOA formation, making it as the secondary important SOA precursor at the XH site. Last but not the least, the influence on photochemical ozone formation related to updates of isoprene degradation was ignorable. Overall, the above results confirmed the insufficient description of the degradation of precursors indeed limited the simulation of the intermediate and secondary products, highlighting the needs of exploring and parameterizing the precursor degradation processes for better understanding of their behaviors and SOA formation in the atmosphere. • 155 new species and related 498 reactions for the oxidation of isoprene were updated and incorporated in a photochemical box model. • The influence of updated degradation mechanisms for isoprene on intermediate and secondary products were estimated. • Large variations of ACR, MVK, Gly, Mgly and SOA were found after the improvement of isoprene degradation mechanisms. [ABSTRACT FROM AUTHOR]