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Mulberry leaf can be used as supplements and functional foods to prevent and alleviate metabolic diseases. Metabolic diseases include obesity, type 2 diabetes, cardiovascular diseases, and non-alcoholic fatty liver diseases. Metabolic diseases may cluster in an individual and are associated with myriad complications and comorbidities. Mulberry leaf is consumed as tea, powder, or extracts to treat and manage health conditions, particularly hyperglycemia and type 2 diabetes. Alkaloids, polyphenols, phytoalexins, polysaccharides, and fibers are the main bioactive compounds in mulberry leaf and they are associated with hypoglycemic, lipid, and urate-lowering activities important for the prevention and managing metabolic diseases. 1-Deoxynojirimycin and fagomine are among the alkaloids in mulberry leaf, which exhibit α-glucosidase inhibitory activity and enhance insulin sensitivity important for glucose homeostasis and hypoglycemic effect. Also, mulberry leaf bioactive compounds provide prebiotic functions to the gut microbiota and are converted into beneficial metabolites in multiple dimensions. This review presents the recent findings on the application of mulberry leaf as a functional food in preventing and alleviating metabolic diseases when consumed as tea or extract. [ABSTRACT FROM AUTHOR]

Vector vortex beams (VVBs) are a promising type of structured light that combine the orbital angular momentum (OAM) and the polarization states of light. Due to their intrinsic high dimensionality, VVBs show great advantages in applications like optical communications, information encryption, and quantum information processing. However, the high dimensionality presents a challenge for pattern detection. In this paper, we compare different machine learning-based methods for classifying 270 classes of VVB using basic CNN, MobileNet, and ResNet18 neural networks. We visualize the VVB modes using a color-coding method with Stokes parameters, and the neural networks' performance is tested in a 1 km free space communication link with four atmospheric turbulence strengths. The results demonstrate that neural networks can recognize large datasets of laser modes with good accuracies, even under turbulence environments. We also propose an image encryption scheme using the VVB dataset to encode an RGB figure which is transmitted through the turbulence channel and successfully recovered by the pre-trained neural networks. Our study highlights the potential of artificial intelligence for VVB pattern recognition and could have a significant impact on the design of future optical communications systems and information encryption protocols. [Display omitted] • Classification of the large structured light dataset (270 classes). • Comparison of three neural networks under different turbulence environments. • Image encryption and transmission using large structured light dataset and pre-trained neural networks. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) because of low-cost fabrication and high performance have shown superb potential for the next-generation photovoltaic application. For the potential applications of photovoltaic technologies, semitransparent PSCs are also highly attractive and of commercial interest to develop building- and tandem-integrated solar cells. Here, we present fully-ambient-processed stable and mesoscopic semitransparent PSCs by non-continuous islands-structure-CH 3 NH 3 PbI 3-x Cl x -NiO nanoparticles (MAPbI 3-x Cl x -NiO NPs) composite and interface engineering by inserting Al 2 O 3 /NiO between TiO 2 and MAPbI 3-x Cl x -NiO composite layers in a device configuration of FTO/c-TiO 2 /mp-TiO 2 /Al 2 O 3 /NiO/islands-structure-MAPbI 3-x Cl x -NiO /spiro-OMeTAD/Au. Except for the islands-structure-MAPbI 3-x Cl x -NiO capping layer, a uniform and thicker and transparent TiO 2 /Al 2 O 3 /NiO/MAPbI 3-x Cl x composite layer is formed, which can effectively reduce photocurrent density loss and interface recombination. Interestingly, the optimized semitransparent PSCs showed hysteresis-free performance. The average visible transmittance (AVT) of MAPbI 3-x Cl x -NiO NPs composite film was ranged from 18% to 56% and the corresponding device PCE changed from 17.51% to 12.47%. The PSCs without encapsulation showed an excellent air stability over 270 days with retaining ~98% of its original V oc , ~96% of J sc , ~97% of FF and ~93% of PCE under ambient condition (25–30 ℃ and 45–50% humidity). Finally, we achieved semitransparent device of PCE = 10.06%, corresponding to AVT = 27%. [ABSTRACT FROM AUTHOR]

Graphene has played the role of game-changer for conductive transparent devices indebted to its unique two dimensional (2D) structures and gained an exceptional opportunity to be employed in energy industry. In the past two decades graphene has been merged with the concept of photovoltaic (PV) material and exhibited a significant role as a transparent electrode, hole/electron transport material and interfacial buffer layer in solar cell devices. This review covers the different methods of graphene fabrication and broadly discusses the recent advances in graphene-based solar cells, including bulk heterojunction (BHJ) organic, dye-sensitized and perovskite solar cell deices. The power conversion efficiency surpassed 20.3% for graphene-based perovskite solar cells and hit the efficiency of 10% for BHJ organic solar cells. Except the part of charge extracting and transport to the electrodes, graphene has another unique role of device protection against environmental degradation via its packed 2D network structure and provides long-term environmental stability for PV devices. We highlighted a comparative study on the role of graphene and its derivatives in photovoltaic devices. After all, the potential issues and the perspective for future research in graphene-based materials for PV applications are presented. [ABSTRACT FROM AUTHOR]

The poor air-stability and reproducibility of perovskite solar cells (PSCs) have prevented the practical applications of the devices that can withstand sustained operation under ambient air conditions. Here, we report all-ambient-air-solution-processed PSCs based on CH 3 NH 3 PbI 3−x Cl x -NiO composite film with inserting Al 2 O 3 /NiO at the TiO 2 /perovskite interface in a cell configuration of FTO/c-TiO 2 /mp-TiO 2 /Al 2 O 3 /NiO/MAPbI 3−x Cl x -NiO/spiroOMeTAD/Au. The interface engineering with Al 2 O 3 /NiO not only improves crystalline quality of perovskite films and enhances charge transport, but also effectively suppresses carrier recombination. This composite-based interface engineering PSCs showed a high power conversion efficiency ( PCE ) of 18.14% and excellent reproducibility with average 16–18% PCE for 35 devices. More importantly, the devices without encapsulation showed a significant enhancement in long-term air-stability; the device photovoltaic parameters stabilized after 20 days and sustained its stability over 210 days with retaining ~100% of its original V oc , ~94% of J sc , ~91% of FF and ~86% of PCE in an ambient environment. [ABSTRACT FROM AUTHOR]

As the head source of the two longest rivers in China and the longest river in Southeast Asia, the East Qinghai-Tibetan Plateau (QTP) is experiencing increasing thaw snowmelt and more heavy precipitation events under global warming, which might lead to soil erosion risk. To understand the potential driving force of soil erosion and its relationship with precipitation in the context of climate change, this study analyzed long-term variations in annual rainfall-runoff erosivity, a climatic index of soil erosion, by using the Mann-Kendall statistical test and Theil and Sen's approach in the Source Region of the Three Rivers during 1961–2012. The results showed the followings: (i) increasing annual rainfall-runoff erosivity was observed over the past 52 years, with a mean relative trend index ( RT 1 ) value of 12.1%. The increasing trend was more obvious for the latest two decades: RT 1 was nearly three times larger than that over the entire period; (ii) more precipitation events and a higher precipitation amount were the major forces for the increasing rainfall-runoff erosivity; (iii) similar rising trends in sediment yields, which corresponded to rainfall-runoff erosivity under slightly increasing vegetation coverage in the study area, implied a large contribution of rainfall-runoff erosivity to the increasing sediment yields; and (iv) high warming rates increased the risk of soil destruction, soil erosion and sediment yields. Conservation measures, such as enclosing grassland, returning grazing land to grassland and rotation grazing since the 1980s, have maintained vegetation coverage and should be continued and strengthened. [ABSTRACT FROM AUTHOR]

Herein, we present a simple, eco-friendly one-step microwave-assisted reduction (MWAR) that can produce silver nanoparticles (Ag NPs) and reduced graphene oxide (rGO) in the form of Ag-rGO composites for application in heterojunction hybrid solar cells. The field-effect transistor fabricated with the MWAR Ag-rGO composite showed p-type behavior with a high mobility of 3.3×10 5 cm 2 V −1 s −1 and conductivity of 9×10 6 S/m which is one-order of magnitude greater than pristine graphene (i.e., 1.59×10 5 S/m). As-synthesized Ag-rGO composite was introduced into the active layer of bulk heterojunction solar cell based on P3HT:PCBM. Compared to the P3HT:PCBM only device (i.e., control device), the Ag-rGO implemented device showed a power conversion efficiency (PCE) of 4.23%, which is about 42% increase over the control device (i.e. PCE=2.98%). This dramatic increase in PCE was found to be mainly due to an increase in short-circuit current ( J sc ) from 9.55 to 12.76 mA/cm 2 (about 33% increase), suggesting that the incorporation of p-type Ag-rGO into the active layer enhances the charge carrier generation and fast extraction of holes to the electrode. Furthermore, the Ag-rGO composite based solar cells without encapsulation showed remarkable air stability with retaining ~90% of its original PCE and ~93% of J sc for 30 days under ambient environment, attributed to gas barrier feature of the randomly distributed graphene sheets. [ABSTRACT FROM AUTHOR]

One of critical issues for practical applications of perovskite solar cells (PSCs) is how to enhance the photocurrent and air stability of the peovskite materials. Here, we report an air-stable, hole-conductor-free (HCF), high photocurrent PSC based on CH 3 NH 3 PbI 3 –NiO nanoparticles (MAPbI 3 –NiO NPs) composite. The composite solution contains highly dispersed NiO NPs in solution of CH 3 NH 3 I(MAI) and PbI 2 in dimethylformamide. By introducing the CH 3 NH 3 PbI 3 –NiO composite into the active layer, the HCF-PSCs with FTO/c-TiO 2 /mp-TiO 2 /MAPbI 3 –NiO/Au architecture have been fabricated under ambient conditions. This composite-based HCF-PSCs show a high photocurrent density ( J sc ) of 26.41 mA/cm 2 , which is 97%of theoretical maximum (i.e., 27.2 mA/cm 2 ). Compared to the power conversion efficiency (PCE) of MAPbI 3 -based HCF-PSC (i.e., 5.43%), the MAPbI 3 –NiO NPs composite-based HCF-PSC showed a high PCE of 12.14%. This increase in PCE is mainly due to a remarkable increase in photocurrent density, suggesting that the MAPbI 3 –NiO composite enhances the charge carrier generation via improving photo-absorption and fast hole-conduction by NiO NPs. More interestingly, the composite-based HCF-PSCs without encapsulation showed remarkable air stability with retaining ~90% of its original PCE and ~94% of both J sc and FF for 60 days under ambient environment. XPS and IR spectra analysis revealed that Ni–O, Pb–O, C–O, Ni–N and N–NiO bonds attributed to strong chemical interaction between NiO and MAPbI 3 molecules enhance the air stability of MAPbI 3 –NiO composite based HCF-PSCs. [ABSTRACT FROM AUTHOR]

Background: Our objective was to examine the role of p38 mitogen-activated protein kinase (MAPK) in ischemia-reperfusion (I/R)-induced recruitment or leukocytes in the colon. Methods: C57/Bl6 mice were subjected to 30 minutes of ischemia by clamping the superior mesenteric artery followed by 2 hours of reperfusion. Animals were pretreated with the selective p38 MAPK inhibitors SB 239063 and SKF 86002 before induction of I/R. Leukocyte-endothelium interactions were quantified by use of intravital fluorescence microscopy. Additionally, the role of p38 MAPK in mast cell-generated tumor necrosis factor-α (TNF-α) as well as neutrophil adhesion and P-selectin expression were examined in vitro. Results: SB 239063 and SKF 86002 decreased both I/R-provoked leukocyte rolling and adhesion by > 75%. Inhibition of p38 MAPK decreased dose-dependently the mast cell generated TNF-α production as well as TNF-α-induced expression of P-selectin and neutrophil adhesion on endothelial cells. Conclusion: We conclude that p38 MAPK regulates leukocyte rolling and adhesion in colonic I/R. Moreover, inhibition of p38 MAPK activity decreases formation of TNF-α and P-selectin–dependent leukocyte attachment to activated endothelial cells. Thus, our findings suggest that interference with the p38 MAPK signaling pathway could be an effective strategy to protect against I/R-induced inflammation in the colon. [Copyright &y& Elsevier]

Stabilization of perovskite phases and interfaces in stacked perovskite photovoltaics are critical for their efficiency, operational stability and perovskite solar modules (PSMs). Herein, A-site cation-size mismatch processed perovskite-composition films with less crystal defects are formed by incorporating larger cations formamidinium and methylammonium with smaller cations, i.e., potassium and cesium. The interface stabilization can be achieved by inserting Poly[bis(4-phenyl) (2,4,6-trimethylphenyl) amine], mesoporous alumina, phenethyammonium ligands and atomic-layer-deposition tin oxides at desired interfaces in inverted perovskite solar cells (PSCs). Thus, the interface defects, non-radiative recombination and ion migration can be remarkably suppressed, resulting in improvement of interface contacts and hole/electron transport. As a result, both cation-size mismatch and interface stabilization (CM-IS) strategies enable hysteresis-free, reproducible 21.9% and 16.9% efficient NiO x -based inverted PSCs and PSMs. Moreover, a high V oc of 1.16 V and 8.05 V can be obtained in large-area PSCs (1 cm2) and PSMs (11.2 cm2) with 7 subcells connected in series. Additionally, the measured T 85 lifetime (the time as a function of PCEs decrease to 85% of its initial value) of unencapsulated PSCs under continuous AM 1.5G light illumination is approximately 1000 h. Phase and interface defects induced non-radiative recombination and instability in inverted perovskite solar cells (PSCs) can be remarkably suppressed by A-site cation-size mismatch and interface stabilization (CM-IS) strategies. Thus, a highly efficient 21.9% and 16.9% NiO x -based inverted PSCs and perovskite solar modules (PSMs) were fabricated. Moreover, a high V oc of 1.16 V and 8.05 V can be obtained in large-area PSCs (1 cm2) and PSMs (11.2 cm2) with 7 subcells connected in series. [Display omitted] • A-site cation-size mismatch processed perovskite compositional films with less crystal defects are formed. • The interface stabilization is employed to reduce interface defects in stacked inverted PSCs. • Inverted PSCs and modules with 21.9% (0.09 cm2) and 16.9% (11.2 cm2) efficiency are fabricated. • Inverted PSCs based on CM-IS strategies show enhanced operational stability over 1000 h. [ABSTRACT FROM AUTHOR]

Segmentation of coronary artery intravascular ultrasound (IVUS) images is the first step in assessing blood vessel morphology and detecting possible atherosclerotic lesions. To overcome the disadvantage of manual acquisition of initial contour in traditional Snake algorithm and construction of external force only from gradient information, an improved Snake algorithm is proposed for automatic outer membrane segmentation in intravascular ultrasound images. Firstly, we design a basic segmentation algorithm to automatically extract the approximate contour of the first frame, and this is iterated as the initial contour of the Snake algorithm. Next, the extended structure tensor is combined with the Snake algorithm to make it part of the external force of the Snake algorithm, and then the curve is evolved to complete the segmentation. To verify the effectiveness of the proposed method, this paper not only shows the experimental results qualitatively, but also quantitatively measures the RMSE and RDD indices. Comparative experiments show that the proposed method not only has higher accuracy, but also has better timeliness. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) based on organometal halide (Omh) perovskites have been exhibited superb potential for next-generation photovoltaic applications because of their ever-increasing power conversion efficiencies over the past decade. However, their operational stability remains a challenge, which are attributed to the ionic nature of Omh perovskites and defects of heterojunction interfaces in a stacked solar cell. Thus, stabilization of Omh perovskites phases and device interfaces are of paramount importance towards long-term stable PSCs. This review presents an important tool to explore efficient and stable PSCs by Omh perovskite-based composites and interface stabilization strategies. Moreover, it deals with the study on materials selection for effective design of Omh perovskite composites and cell heterojunction interfaces. The chemical and electrical characteristics of Omh perovskite composites and device interface states, including perovskite film growth, defect tolerance, interface trap passivation, strong chemical interaction, cross-linking and/or chemical bonding, are further discussed. These features provide insights into the stabilization and immobilization of Omh perovskite structures and stacked solar cell interfaces for highly efficient and stable perovskite photovoltaics. Recent progress in materials innovation and interface stabilization for highly efficient and operationally-stable perovskite photovoltaics. [Display omitted] • Degradation factors and their mechanisms in perovskite photovoltaics are briefly analyzed. • Judicious strategies to stabilize perovskites phases and solar cell heterojunction interfaces are reviewed. • Key works related to efficient perovskite photovoltaics by materials innovation and interface stabilization are presented. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) demonstrated a record-high power conversion efficiency, but they have instability issues attributed to the degradation of materials and device performance. To overcome the instability problem and performance degradation, various methods have been proposed, but still need a comprehensive solution. Here, we propose an innovative way of insuring device performance and long-term stability by utilizing functional composites of perovskite, nickle oxide and graphene into device structures. We fabricated the PSCs based on MAPbI 3−x Cl x /NiO-graphene photoactive composite and NiO interface layer. Compared to the pristine perovskite cells, the champion device based on the photoactive composites with NiO interface showed remarkably high photocurrent density of 25.9 mA/cm2 (i.e., 95.2% of theoretical maximum) and power conversion efficiency of 20.8% without J-V hysteresis. More impressively, unencapsulated cells showed significant improvement of thermal- and photo- and long-term air-stability with retaining 97–100% of the initial values of performance parameters over 310 days under ambient conditions. Schematic illustration of a perovskite solar cell structure based on MAPbI 3−x Cl x /NiO-rGO composite photoactive layer and NiO interface formed on the SrTiO 3 /Al 2 O 3 -graphene electron transfer layer, exhibiting the mechanism of charge carrier separation and conduction through graphene and connected NiO nanoparticles and blocking moisture and oxygen infiltration. ga1 • Highly stable and efficient composites-based perovskite solar cells. • Perovskite/NiO-graphene photoactive composite and NiO interface layer. • Remarkably high photocurrent density and power conversion efficiency without J-V hysteresis. • Significant improvement of thermal- and photo- and air-stability with retaining 97–100% of device performance over 310 days. [ABSTRACT FROM AUTHOR]

For commercialization of perovskite solar cells (PSCs), the device stability issues attributed to degradation of perovskite material, photo and thermal instability, and photocurrent density-voltage (J - V) hysteresis behavior should be solved. Furthermore, most of presented high efficiency PSCs utilize an antisolvent-strategy to assist perovskite crystal growth with large grain-size and excellent coverage. To solve such issues, we developed fully-ambient-air and antisolvent-free processes for the fabrication of PSCs with perovskite-based composites (i.e., MAPbI 3-x Cl x -Cu:NiO, MAPbI 3-x Cl x -Cu:NiO-carbon-graphite and MAPbI 3-x Cl x -Al 2 O 3). Such perovskite composites based cells with interface engineering yielded high power-conversion-efficiency (PCE) of 18.6% and fill factor (FF) of 78.3% with excellent reproducibility. More importantly, the target cells showed hysteresis-free behavior and dramatic enhancement in air-, photo- and thermal-stability. Compared to the pristine cells, the target device showed remarkable long-term stability with retaining almost 100% of the initial values of V oc and J sc , and ~94% of FF and PCE over 280 days. Schematic illustration and conceptual mechanism of stable perovskite solar cells by perovskite-based-composites and interface engineering. Image 1 • Fully-ambient-air and antisolvent-free processes for highly stable perovskite solar cell. • Perovskite-based composites with interface engineering with Al 2 O 3 /Cu:NiO. • Dramatic enhancement of air-, photo- and thermal-stability with hysteresis-free behavior. • Long-term stability with retaining initial values of photovoltaic parameters over 280 days. [ABSTRACT FROM AUTHOR]

In this paper, an environmentally friendly and facile method for the synthesis of CuCo 2 O 4 nanosheets using deep eutectic solvent was reported. The synthesized CuCo 2 O 4 nanosheets were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), zeta potential research, Brunauer-Emmett-Teller (BET) surface area analysis, Fourier transform infrared spectroscopy (FT-IR), diffuse reflectance spectroscopy (DRS) and photoluminescence (PL) techniques. The CuCo 2 O 4 nanosheets were successfully applied in degradation of organic dyes based on excellent photocatalytic activity. In the photocatalytic system, with 15 mg catalyst, 99.96% Methyl orange, 99.89% Congo red and 99.90% Amaranth (MO: 300 mg L−1, CR:300 mg L−1, AM: 80 mg L−1) in 200 mL solution were degraded in 120 min, respectively. Then, it was proved that removal of dyes was made up of original Langmuir adsorption and first order kinetics. Moreover, the nanomaterial could be reused for six cycles with slight decline of degradation efficiency, proving its high stability. In addition to good photocatalytic activity, the nanomaterial exhibited excellent antimicrobial activity against Escherichia coli and Staphylococcus aureus, achieving a complete bactericidal effect at a concentration of 100 μg mL−1. In conclusion, the as-synthesized nanomaterial had high photocatalytic activity and good antibacterial activity, which was expected to be applied in practical wastewater treatment. Proposed reaction mechanism for dyes decomposition by CuCo 2 O 4 nanosheets. [Display omitted] • The novel CuCo 2 O 4 nanosheets was Synthesized by deep eutectic solvent. • Simultaneous bacteria inactivation and pollutants removal was investigated. • Nanomaterial had excellent disinfection ability toward E.Coli and S.aureus bacteria. • The antibacterial mechanism and dye degradation mechanism was investigated. [ABSTRACT FROM AUTHOR]

Abstract: Loquat (Eriobotrya japonica Lindl.) fruit were stored in air at 25°C, modified atmosphere packaging (MAP, polyethylene bag of 0.01mm thickness) at 1 and 6°C, controlled atmospheres (CA) of 10% O2 +1% CO2 and, CA with 70% O2 treatment for 24h at first, then stored in CA with 10% O2 +1% CO2 at 1°C, to determine the effects of atmospheres and temperatures on quality attributes, physiological properties and storability during storage periods. The results indicated CA with 10% O2 +1% CO2 was more effective in reducing fruit decay, SSC/TA, pH, activities of endo-PG and exo-PG, inhibiting ethyl acetate accumulation in fruit, inducing ethanol accumulation in fruit at later storage period in comparison with MAP treatment. Loquat fruit could be stored in this CA condition at 1°C for more than 50d with normal flavour and low decay index of about 7%. Short term high-O2 treatment at the beginning of storage had little effect on fruit flavor, but stimulated ethanol accumulation in loquat fruit, and reduced activities of endo-PG and exo-PG. MAP treatment showed more effectiveness in reducing fruit decay, off-flavor and weight loss at 1°C than at 6°C. CA conditions were more effective for reducing the activities of PPO and oxidative stress compared to other treatments, which may be the reason why loquat fruit stored in CA conditions had lower decay index than that kept in other conditions. [Copyright &y& Elsevier]

The addition of 2% (w/v) sodium bicarbonate (SBC) in the suspensions of antagonistic yeast Cryptococcus laurentii or Trichosporon pullulans significantly limited spore germination and germ tube elongation of Penicillium expansum and Alternaria alternata in potato dextrose broth (PDB) medium. Biocontrol activity of C. laurentii or T. pullulans against postharvest decay caused by P. expansum and A. alternata in pear fruits was significantly increased when C. laurentii or T. pullulans combined with SBC. Combining C. laurentii or T. pullulans with SBC provided a more effective control on P. expansum and A. alternata than applying the antagonistic yeast or SBC alone. Effects of C. laurentii with and without SBC on controlling P. expansum and A. alternata were better than those of T. pullulans. C. laurentii in combination with SBC showed the best control of disease caused by A. alternata in pear fruits. [Copyright &y& Elsevier]

High quality, closely packed nanorods (NRs) textured ZnO hollow particles were prepared via thermal treatment of polystyrene@ZnO core-shell structures at 300 °C. Polystyrene@ZnO core-shell structures were synthesized using a chemical route. These hollow ZnO particles were investigated for hydrogen gas sensing properties. Morphological properties were studied using field emission scanning electron microscope (FE-SEM). Structural parameters and molecular fingerprint confirmation were carried out by x-ray diffraction (XRD) and Raman analysis respectively. The elemental compositions and atomic species of sensor materials were studied using energy dispersive spectrometer (EDS) analysis and x-ray photoelectron spectroscopy (XPS) spectra respectively. The study of atomic planar arrangements and crystalline nature were examined by using a high-resolution transmission electron microscope (HR-TEM) micrograph and selected area electron diffraction (SAED) pattern respectively. Hollow ZnO particles sensor was revealed remarkable selectivity towards hydrogen (H 2) gas. The lowest H 2 detection limit of ZnO sensor was at 2 ppm with the response of 7%, whereas 89% gas response was recorded for 100 ppm at optimized temperature 225 °C with response time 139 s. Gas response as a function of operating temperatures as well as gas concentrations was tested along with good sensor stability. The transient gas response and selectivity studies were carried out and analyzed. ZnO growth and gas sensing mechanisms were elucidated. Image 1 • Hollow ZnO spherical microparticles formation from polystyrene@ZnO core-shell. • Easy growth of ZnO nanorods on polystyrene micron particles with mechanism. • Detail structural analysis using XRD data, and materials characterizations. • High transient gas response, stability with better selectivity towards H 2 at 225 °C. • H 2 gas detection in range 2–100 ppm by hollow ZnO sensor with fast response. [ABSTRACT FROM AUTHOR]

Abstract The future trend of water and sediment variation is closely related to the governance of the Yellow River. The increasingly frequent occurrence of extreme rainfall events has rendered the future water and sediment situation of the Yellow River uncertain. Understanding the characteristics of flood and sediment yield of the river basin under extreme rainfall conditions at different times is a prerequisite and foundation for accurate prediction of water and sediment situation in the Yellow River in the future period. We here used the July 26 extraordinary rainstorm event in 2017 in the Wuding River as a starting point for revealing the law of flood and sediment yields changes under extreme rainfall conditions around the year 2000. The results indicated that, during the period from 1960 to 2016, the average proportion of extreme rainfall depth in the middle Yellow River region over the total precipitation depth increased by 5.1%. Areas where extreme rainfall events frequently occur showed a trend of developing from localized regions in the Toudaoguai–Longmen reach to the majority of the middle reaches. There were obvious changes in the rainfall-flood and rainfall-sediment relations under extreme rainfall conditions. Compared with historical extreme rainfall events, the decline in flood and sediment yield in the river basin after 2000 under similar rainfall and intensity conditions was obvious. Among these results, flood decreased by 30.4–78.2%, sediment yield was decreased by 53.0–88.2% and sediment content in flood was decreased by >47.2% on average when compared with the same rainfall conditions in the previous century. Comparative watershed studies showed that, during extreme rainfall events, areas under soil and water loss management programs suffer 57.2% and 75.7% less flood runoff modulus and sediment transport modulus, respectively, than non-managed areas. This indicates that soil and water loss management is the major driving factor for changes in rainfall-flood and rainfall-sediment relations under extreme rainfall conditions. This study highlights the importance of soil and water loss management in the flood control and sediment reduction. We concluded that, with the implementation of soil and water conservation measures, the probability of large flood and sediment events will greatly decrease and the amount of sediment entering the Yellow River under extreme rainfall will further decrease in the next 30 years. Highlights • Frequency of extreme rainstorm events in the Yellow River increased significantly. • Rainstorm-sediment relations exhibited obvious changes after 2000. • Soil and water loess management plays a key role in reducing sediment. • The probability of large flood and sediment events will greatly decrease. [ABSTRACT FROM AUTHOR]

Highlights • Fruit stalk retention helped to maintain peach fruit quality during chilling storage. • Fruit stalk retained membrane integrity and reduced MDA level during chilling storage. • Fruit stalk retention reduced the maximum H2O2 peak level during chilling injury (CI). • Fruit stalk retention prevented the decline of antioxidant enzymes activity during CI. Abstract Chilling injury (CI) is a physiological disorder of peach fruit, occurring at low temperature storage, especially at 5 °C. In this study, the influence of fruit stalk retention on fruit quality and reactive oxygen species (ROS) metabolism of white-fleshed peach (cv. Okubo) was investigated. Fruit with and without stalk was exposed to chilling condition and subsequent shelf-life at 20 °C. Fruit physiological changes and ROS metabolism were monitored. The results showed that stalk retention effectively maintained fruit membrane integrity and reduced juice extraction rate under CI condition. ROS metabolism assay revealed that retention of fruit stalk significantly maintained activities of ascorbate peroxidase (APX), peroxidase (POD), and catalase (CAT), and reduced the peak level of hydrogen peroxide (H 2 O 2) of fruit stored at 5 °C. Multivariable analysis (principal component, partial least squares and path analyses) demonstrated that the improvement of fruit quality indexes such as membrane integrity due to stalk retention was mainly achieved by maintaining APX and POD activities. [ABSTRACT FROM AUTHOR]

Core browning is a major issue of pear fruits. The primary factor leading to development of core browning is high levels of CO 2 in storage. Hypobaric storage is a new postharvest technique to extend the shelf life of fruits and can reduce CO 2 partial pressure. In this study, the effect of hypobaric storage on core browning of Yali pear fruits ( Pyrus bretschneideri Rehd.) was evaluated. Results showed that fruits after 0.025 MPa hypobaric treatment had 37.3% lower rate of core browning development and higher acidity and soluble solid content than control fruits. In addition, 0.025 MPa hypobaric treatment increased activities of cytochrome oxidase (CCO) and peroxidase (POD), and 2,2-diphenylpicrylhydrazyl (DPPH) radicals and superoxide anion scavenging capabilities. In comparison with the control, hypobaric treated fruits had lower activity of polyphenol oxidase (PPO) and higher level of total polyphenols. Hypobaric treatment also reduced an increase of succinate dehydrogenase (SDH) and glucose-6-phosphate dehydrogenase (G-6-PDH) activities. Results indicated that hypobaric treatment could control core browning of pear fruits by regulating reactive oxygen species (ROS) generation and elimination enzymes to maintain cell membrane integrity and reduce enzymatic browning. [ABSTRACT FROM AUTHOR]

• High CO 2 concentrations caused core browning. • Core browning and damage of cellular membrane increased in 4% CO 2 condition. • H 2 O 2 and malondialdehyde increased in 4% CO 2 condition. • CO 2 regulate electron transport chain and reactive oxygen species scavenging enzymes. Pears may be affected by core browning during storage, reducing their commercial value. The effect of CO 2 stress on the core browning process in Yali pears was investigated. Exposure to a 4% CO 2 atmosphere significantly increased the core browning and reduced titratable acidity and soluble solids content. The activity of succinate dehydrogenase and peroxidase was reduced in CO 2 -stressed pears, whereas the levels of H 2 O 2 and malondialdehyde were increased. Transmission electron microscopy revealed significant damage to cellular membrane structure in the core tissues of CO 2 -stressed pears. In addition, CO 2 -stressed pears showed increased polyphenol oxidase activity. These results suggest that high concentrations of carbon dioxide can accelerate core browning in pears by inhibiting the activities of enzymes in the electron transport chain, resulting in increased levels of free radicals that damage cellular membranes. [ABSTRACT FROM AUTHOR]

• Hypobaric storage effects on blueberry bioactive, antioxidants and ROS were studied. • Storage at 0.025 MPa was more suitable for retention of blueberry bioactive compounds. • Multivariate PLSR analysis revealed that ROS were negatively correlated with anthocyanin, POD, CAT, SSC, flavonol and antioxidant capacity. • Blueberries can be stored up to 50 days under hypobaric storage. This paper studies the effects of hypobaric storage on the physiochemical quality of the Northland blueberry fruits, as well as their bioactive compounds, pre- and pro-antioxidant enzymes and reactive oxygen species (ROS). Different hypobaric pressures at 0.025, 0.05 and 0.075 MPa were applied to stored blueberry at 0 °C. Hypobaric treatment resulted in lower fruit decay rate compared to control, maintained respiration rate and pH of the fruit for 0.05 and 0.075 MPa treatments, which implied that fruit freshness was maintained following hypobaric storage. Also, hypobaric storage significantly retained high bioactive compounds (P < 0.05), especially total flavonol and anthocyanins after 50 days storage at 0.025 MPa compared to control. The retained bioactive compounds were reflected as high antioxidant capacity indicated by DPPH, FRAP and TEAC. The treatment 0.025MPa displayed the lowest MDA activity on day 23 and highest on day 50, which reflected delayed oxidation by hydrogen peroxide. Evidently, high levels of POD, APX, PPO and GSH antioxidant enzymes in the 0.025 MPa stored blueberries may be due to delayed ROS metabolism. Partial least square regression (PLSR) model showed that, ROS were negatively correlated with anthocyanin, POD, CAT, SSC, flavonol, TEAC, FRAP, DPPH as well as hydroxyl radical scavenging ability. Similarly, path analysis (PA) revealed that MDA was negatively correlated with TEAC, TA and fruit pH, while hydrogen peroxide was negatively correlated with GSH and protein. Of the pressures, 0.025 MPa was selected as the suitable hypobaric pressure for Northland blueberry storage as significantly retained studied indexes at relatively high values throughout 50 days storage. [Display omitted] [ABSTRACT FROM AUTHOR]

• Yeast cell wall component as MAMPs stimulated disease resistance of cherry tomato fruit. • The resistance mechanism is associated with induction of related defense genes expression. • SlMAPK3 played as a key upstream signaling kinase responding yeast cell wall induction. • SlMAPK3 could directly regulate the expression of specific transcription factors and PR genes. Induced disease resistance of fruit by bio-based compounds is a promising strategy to control fruit decay. This research was aimed at studying the resistance of cherry tomato fruit to Botrytis cinerea induced by the yeast cell wall component from Saccharomyces cerevisiae and investigate a role of MAPKs in regulating the resistance response. The disease resistance of cherry tomato fruit was effectively enhanced by yeast cell wall and β-glucan. The expression of SlMAPK3 (but not of SlMAPK1 and SlMAPK2) was significantly increased by yeast cell wall and β-glucan and reached peak at 1 h. The yeast cell wall component also induced high expression of PR genes (SlPR1 , SlPR5 and SlCHI9) and the transcription factors (SlERF1 and SlPti5) that specifically bind to the promoter of PR genes. The expression of PR genes (SlPR1 , SlPR5 and SlCHI9) peaked after 24 h (at 24 or 48 h). The peak of SlERF1 and SlPti5 gene expression mostly appeared at around 4 h. It supposed to be a chronological order in the peaks of gene expression profile among SlMAPK3 , PR genes and transcription factors. U0126 (1,4-diamino-2,3-dicyano-1,4-bis(o-amino-phenylmercapto)butadiene) significantly inhibited transcription of SlMAPK3, PR g enes and transcription factors. The yeast cell wall and β-glucan could not induce high expression of SlMAPK3 and the downstream genes of SlMAPK3 in the U0126 treatment. These findings indicated that the yeast cell wall component that acts as microbe associated molecular patterns (MAMPs) could effectively induce disease resistance in cherry tomato fruit after harvest. The mechanism of induced resistance was associated with the expression of SlMAPK3 and defense-related genes. SlMAPK3 , as an important upstream signaling kinase, had a direct regulatory effect on the downstream transcriptional factors (SlERF1 and SlPti5) to activate the expression of PR genes in the yeast cell wall component-induced immune responses in cherry tomato fruit. [ABSTRACT FROM AUTHOR]