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The white light emitting diodes (LEDs) devices based on the use of blue chips and yttrium aluminum garnet phosphors have great potential impact on energy savings in the world. However, there has been public concern over the non-visual influences of blue light on human health. Herein, we report a high-gravity-hydrolysis approach for the synthesis of transparent nanozirconia/silicone hybrid materials, which can be used as the encapsulation of white LEDs with enhanced light extraction efficiency and reduced blue light exposure. The formation of zirconia nanoparticles on silicone chains is performed in a high-gravity rotating packed bed (RPB) reactor. The homogeneous micromixing of the reactants in the RPB enables the formation of ultrasmall zirconia nanoparticles in the silicone chains. Compared with LEDs encapsulated with commercial silicone, the white LEDs packaged by nanozirconia/silicone exhibit significant enhanced luminous flux (from 13.28 to 31.34) and decreased proportion of blue light (from 3.1% to 1.8%), resulting in low correlated color temperature (4573 K). This work demonstrates a scalable and efficient approach for healthy lighting based on the commercial white LEDs technology. Image 1 • High-gravity-hydrolysis approach for scalable synthesis of nanozirconia/silicone. • The luminous flux of LEDs was enhanced from 13 to 31 by nanozirconia doping. • Proportion of blue light from the LEDs was decreased from 3.1% to 1.8%. [ABSTRACT FROM AUTHOR]

Background Agaricus bisporus is the mushroom with the highest global production yield. However, due to their natural unprotected structure, shelf-life of this kind of mushroom is quite short. During the postharvest period, mushroom experiences continuous quality degradation, presenting discolouration, moisture loss, texture changes, microbial count increasing, and nutrient and flavour loss. In order to maintain the postharvest quality and to extend the shelf-life of mushroom, postharvest preservation techniques including physical, chemical and thermal processes are essential. Scope and approach This review summarises quality degradation processes of mushrooms including moisture loss, discolouration, texture changes, microbial count increasing, and nutrients and flavour loss, analyses their influential factors including temperature, relative humidity, water activity, and respiration rate, and presents the preservation methods for mushrooms including drying, cooling, packaging, irradiation, washing, and coating. Key findings and conclusions The quality degradation process of mushrooms is complex, which is affected by both the inner factors related to mushroom itself and the outer factors related to storage conditions. For better preserving their postharvest quality, hybrid methods such as thermal techniques combined with physical or chemical techniques and novel non-thermal technologies including plasma, ultrasound and high pressure treatments are highly recommended. [ABSTRACT FROM AUTHOR]

Zero-valent iron has been intensively investigated in chemical reduction of nitrate in water, but the reduction requires acidic or weak acidic pH conditions and the product of the reduction is exclusively ammonium, an even more toxic substance. Zero-valent aluminum is a stronger reductant than iron, but its use for the reduction of aqueous nitrate requires considerably alkaline pH conditions. In this study, aluminum-iron alloys with an iron content of 10%, 20% and 58% (termed Al-Fe10, Al-Fe20 and Al-Fe58, respectively) were investigated for the reduction of aqueous nitrate. Al-Fe alloys were efficient to reduce nitrate in water in an entire pH range of 2–12 and the reduction proceeded in a pseudo-first order at near neutral pH conditions. The observed reaction rate constant (K obs ) of Al-Fe10 was 3 times higher than that of Fe and the K obs of Al-Fe20 doubled that of Al-Fe10. The nitrogen selectivity of the reduction by Al-Fe10, Al-Fe20 and Al-Fe58 was 17.6%, 23.9% and 40.3%, respectively at pH 7 and the nitrogen selectivity by Al-Fe20 increased from 18.9% at pH 2–60.3% at pH 12. The enhanced selectivity and reactivity of Al-Fe alloys were likely due to the presence of an intermetallic Al-Fe compound (Al 13 Fe 4 ). [ABSTRACT FROM AUTHOR]

The prediction of moisture content uniformity on mango slices as affected by four different shapes (square, rectangle, regular triangle, and round shape) during microwave-vacuum drying (MVD) was investigated using near-infrared hyperspectral imaging in combination with multivariate chemometric analysis. Applying spectral pretreatment of a 2nd derivative followed by mean-center to raw spectra was found to be greatly beneficial for the reduction of noise and scattering levels. Seven wavelengths (951, 977, 1138, 1362, 1386, 1420, and 1440 nm) with larger absolute values of regression coefficients derived from a partial least square regression model were identified as feature variables for moisture prediction. An optimized model based on the selected wavelengths was developed using multivariate linear regression, achieving a high prediction accuracy with R p 2 = 0.993 and RMSEP = 1.282%. From the moisture distribution map, a similar non-uniform drying pattern was found on square, rectangle and regular triangle-shaped samples, while round-shaped mango slices achieved better drying results. Industrial relevance The current study suggested that NIR hyperspectral imaging was a promising technique in predicting the moisture content of mango slices during MVD, and non-uniformity of moisture distribution and the effect of sample geometry should be taken into account when the microwave-vacuum method is implemented in drying. [ABSTRACT FROM AUTHOR]

Mango slices were dried by microwave-vacuum drying using a domestic microwave oven equipped with a vacuum desiccator inside. Two lab-scale hyperspectral imaging (HSI) systems were employed for moisture prediction. The Page and the Two-term thin-layer drying models were suitable to describe the current drying process with a fitting goodness of R 2 = 0.978. Partial least square (PLS) was applied to correlate the mean spectrum of each slice and reference moisture content. With three waveband selection strategies, optimal wavebands corresponding to moisture prediction were identified. The best model RC-PLS-2 ( R p 2 = 0.972 and RMSEP = 4.611%) was implemented into the moisture visualization procedure. Moisture distribution map clearly showed that the moisture content in the central part of the mango slices was lower than that of other parts. The present study demonstrated that hyperspectral imaging was a useful tool for non-destructively and rapidly measuring and visualizing the moisture content during drying process. [ABSTRACT FROM AUTHOR]

Nitrate contamination is increasingly becoming a global health and environmental issue, because nitrate concentration in ground and surface waters has exceeded the safe limit in many places of the world. Removal of such low levels of nitrate from water by conventional processes in an efficient and cost-effective manner poses a significant challenge in water treatment industry. Chemical reduction using zero-valent iron and aluminum particles for nitrate removal from water has been extensively investigated. In this study, aluminum–iron alloy particles (containing 10% iron) were investigated for removal of nitrate from water and compared with zero-valent aluminum, iron and mixtures of aluminum and iron particles. The aluminum–iron alloy and metallic aluminum particles were inactive for nitrate reduction due to the presence of ubiquitous aluminum oxide layer on surface of the particles. Nitrate reduction was significantly promoted by copper chloride and the alloy particles showed the fastest rate and largest efficiency of the reduction. The significant promotion of the reduction was likely due to the catalytic effect of copper and an intermetallic alloy compound Al 13 Fe 4 . The catalytic mechanism of nitrate reduction by the alloy material was analyzed and the reduction pathway was identified as nitrite and ammonium to be intermediate and end product, respectively. [ABSTRACT FROM AUTHOR]

Abstract: We determined earlier that the hepatoma upregulated protein (HURP) is overexpressed in hepatocellular carcinoma (HCC), but the role of this protein during cancer development and progression remains unknown. Here, we observed that the overexpression of HURP in HEK293 cells promoted the ubiquitination of p53 and its degradation by the proteasome. In contrast, HURP knockdown using short-hairpin RNA reversed these effects. Knockdown of HURP promoted the accumulation of p53 in SK-Hep-1 cells (p53+/−), and these cells showed reduced proliferation, while the p53-mutant Mahlavu cells were not affected. HURP knockdown did not affect the proliferation of H1299 lung carcinoma cells and Hep3B HCC cells which lack p53. Knockdown of HURP also sensitized SK-Hep-1 cells to cisplatin. On the other hand, the expression of exogenous p53 in H1299 and Hep3B cells was decreased following overexpression of HURP, and these cells showed decreased sensitivity to cisplatin-induced apoptosis. Importantly, overexpression of HURP promoted the proliferation of HEK293 cells in an anchorage-independent manner, and inoculation of SK-Hep-1 cancer cells that expressed short-hairpin RNA to knockdown HURP resulted in smaller tumors in nude mice. Gankyrin, a positive regulator of the E3 ubiquitin ligase MDM2, was found to be upregulated following HURP expression, and gankyrin knockdown decreased the HURP-mediated downregulation of p53. Notably, we detected a positive correlation between elevated HURP and gankyrin protein levels in HCC patients (r 2 =0.778; N =9). Taken together, these results indicate that HURP represents an oncogene that may play a role in HCC progression and chemoresistance. [Copyright &y& Elsevier]

Abstract: Spinel ferrite Co x (Cu0.5Zn0.5)1−x Fe2O4 over a compositional range 0< x <1 was prepared using a simple hydrothermal method. Particle sizes could be varied from 14 to 25nm by changing the x value. X-ray diffraction results confirmed that all the as-prepared nanoparticles revealed typical spinel structure and transmission electron microscopy images showed that the particle size of the samples increased with increasing x value. The magnetic properties of the as-prepared Co x (Cu0.5Zn0.5)1−x Fe2O4 nanoparticles have been systematically examined. The maximum saturation magnetization existed at the highest Co content (x =1). The electromagnetic properties of all the samples have been measured by an Agilent network analyzer and the results showed that Co0.1(Cu0.5Zn0.5)0.9Fe2O4 possessed the best microwave absorbing properties. [ABSTRACT FROM AUTHOR]

Abstract: Co–Cu–Zn doped Fe3O4 nanoparticles can be successfully synthesized using a simple method. The particles in the size range 20−400nm with different regular shapes i.e. sphere-like, regular hexane and tetrahedron are controllably achieved by changing the metal ion concentration. Compared to pure Fe3O4 without dopants, Co–Cu–Zn doped Fe3O4 nanoparticles exhibit better microwave absorbing properties at 2−18GHz. Among three Co–Cu–Zn doped Fe3O4 nanoparticles with different morphologies, tetrahedral Co–Cu–Zn doped Fe3O4 nanoparticles represent a better dielectric loss in high frequency range. This work is believed the first known report of Co–Cu–Zn doped Fe3O4 nanoparticles with tunable morphology and magnetic properties through the hydrothermal process without using any organic solvents, organic metal salts or surfactants. [Copyright &y& Elsevier]

Abstract: Co0.2Cu0.03Fe2.77O4 nanoparticles with different morphologies have been synthesized directly via a simple hydrothermal method. The effects of pH value, precursor concentration, reaction temperature and surfactant on the particle size were discussed. X-ray diffraction analyses showed that the as-synthesized Co0.2Cu0.03Fe2.77O4 nanoparticles possessed typical spinel structure. Scanning electron microscope images showed different morphologies of the particles, including truncated octahedron and octahedron. It was indicated that well-dispersed Co0.2Cu0.03Fe2.77O4 nanoparticles can be synthesized at pH values ranging from 11 to 13, and reaction temperature of 160°C. The particle size decreased from 18 to 10nm after the addition of sodium dodecyl sulphate at the pH value of 9. The magnetic measurement showed that the as-prepared Co–Cu spinel ferrite nanoparticles possessed hard magnetic property. [Copyright &y& Elsevier]

Recent studies have profiled the innate immune signatures in patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and suggest that cellular responses to viral challenge may affect disease severity. Yet the molecular events that underlie cellular recognition and response to SARS-CoV-2 infection remain to be elucidated. Here, we find that SARS-CoV-2 replication induces a delayed interferon (IFN) response in lung epithelial cells. By screening 16 putative sensors involved in sensing of RNA virus infection, we found that MDA5 and LGP2 primarily regulate IFN induction in response to SARS-CoV-2 infection. Further analyses revealed that viral intermediates specifically activate the IFN response through MDA5-mediated sensing. Additionally, we find that IRF3, IRF5, and NF-κB/p65 are the key transcription factors regulating the IFN response during SARS-CoV-2 infection. In summary, these findings provide critical insights into the molecular basis of the innate immune recognition and signaling response to SARS-CoV-2. • SARS-CoV-2 replication induces a delayed IFN response in lung epithelial cells • MDA5 and LGP2 are the major sensors recognizing SARS-CoV-2 infection • Viral intermediates activate the IFN response through MDA5-mediated sensing • IRF3, IRF5, and NF-κB/p65 are required for the IFN response induced by SARS-CoV-2 The molecular events that underlie innate immune recognition and response to SARS-CoV-2 infection remain unclear. Yin et al. report that SARS-CoV-2 replication induces a delayed interferon (IFN) response that is triggered by sensing of viral RNA through the MDA5 pattern recognition receptor. [ABSTRACT FROM AUTHOR]

Real-time process/product monitoring can be achieved using suitable process analytical technologies (PAT) to improve process efficiencies and product quality. In the dairy industry, near infrared (NIR) spectroscopy has been utilised as a laboratory analytical method (off-line) for compositional analysis of dairy products since the 1970s. Recent advances in NIR technology and instrumentation have widened its applications from a bench-top analytical instrument to a promising PAT tool for on-line and in-line implementation. This review focuses on the use of NIR technology for real-time monitoring of dairy products, by briefly outlining the measurement principle, NIR instrument configurations, in-line sampling methods, calibration models development, some practical considerations for process installation, and current state of the art in on-line and in-line NIR applications (2012 to date) for continuous process monitoring in the production of dairy products. The challenges and additional resources required to improve production efficiencies using NIR spectroscopy are also discussed. [ABSTRACT FROM AUTHOR]

Highlights • A high-gravity-assisted method for efficient synthesis of zirconia nanoparticles. • Highly dispersed zirconia nanoparticles in organic solvents and epoxy resin. • Significant enhanced light extraction efficiency of LEDs by zirconia nanodispersion. Abstract Zirconia-based hybrid polymers has become one of the ideal encapsulation material for light emitting diodes (LEDs) with high extraction efficiency due to their proper refractive index to those of semiconductor chips. However, the controlling of the dispersion for zirconia nanoparticles in polymeric hosts to obtain optically transparent hybrid nanocomposites has been one of the major challenges. Herein, we reported the synthesis of zirconia nanodispersion via high-gravity-assisted homogeneous precipitation in an internal circulation rotating packed bed (RPB) reactor followed by two-step modification. An alternative to conventional precipitation in batch stirred tank reactors (STR), the process intensification by high-gravity RPB results in homogeneous micromixing during the nucleation and growth of zirconia particles, which are benefit for continuous and reproducible production of ultrasmall zirconia nanoparticles. The obtained zirconia nanoparticles are purely cubic phase with narrow size-distribution in the range of 3–5 nm according to the X-ray diffraction and transmission electron microscopy characterization, which were similarity to that by the conventional methods. Nevertheless, the average hydrodynamic diameters of zirconia nanoparticles in aqueous solutions obtained by RPB methods were much smaller than those prepared in conventional STR, which enabled easy control and surface modification for highly dispersed nanodispersion in organic solvents and/or polymeric hosts. After two-step surface modification, zirconia nanoparticles with goal-directed structures were obtained, with highly dispersity in various organic solvents (e.g. toluene, trichloromethane, tetrahydrofuran, etc.) and aliphatic epoxy resin, forming transparent hybrid films with tunable refractive indexes. The preliminary applications of these zirconia nanodispersions for LEDs encapsulation were demonstrated. The light extraction efficiency of the LEDs devices packaged with zirconia/epoxy hybrid material increased by 10 percent when the doping content of zirconia nanoparticles was 0.2, compared to the devices encapsulated by original epoxy. [ABSTRACT FROM AUTHOR]