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Virus-like particles (VLPs) are nano-scale particles that are morphologically similar to a live virus but which lack a genetic component. Since the pandemic spread of COVID-19, much focus has been placed on coronavirus (CoV)-related VLPs. CoVs contain four structural proteins, though the minimum requirement for VLP formation differs among virus species. CoV VLPs are commonly produced in mammalian and insect cell systems, sometimes in the form of chimeric VLPs that enable surface display of CoV epitopes. VLPs are an ideal model for virological research and have been applied as vaccines and diagnostic reagents to aid in clinical disease control. This review summarizes and updates the research progress on the characteristics of VLPs from different known CoVs, mainly focusing on assembly, in vitro expression systems for VLP generation, VLP chimerism, protein-based nanoparticles and their applications in basic research and clinical settings, which may aid in development of novel VLP vaccines against emerging coronavirus diseases such as SARS-CoV-2.

High-performance two-stage bipolar cascade 905nm vertical cavity surface emitting lasers (VCSELs) are designed and fabricated. Three different designs are investigated to compare the electrical and optical properties. Experimental results show that the current spreading and thermal problems are important factors affecting the device performance. The device with two oxide apertures accompanied with a $1.5\lambda $ -long active region spacing exhibits a very high slope efficiency of 2.27W/A and a relatively high power conversion efficiency of 52.4%. Such high-performance bipolar cascade VCSELs with 905nm are very important for LiDAR and automotive applications.

Severe acute respiratory syndrome coronavirus (SARS-CoV)-2 is responsible for the COVID-19 pandemic that has caused unprecedented loss of life and economic trouble all over the world, though the mechanism of its replication remains poorly understood. In this study, antibodies were generated and used to systematically determine the expression profile and subcellular distribution of 11 SARS-CoV-2 nonstructural replicase proteins (nsp1, nsp2, nsp3, nsp5, nsp7, nsp8, nsp9, nsp10, nsp13, nsp14, and nsp15) by Western blot and immunofluorescence assay. Nsp3, nsp5, and nsp8 were detected in perinuclear foci at different time points, with diffusion and stronger fluorescence observed over time. In particular, colocalization of nsp8 and nsp13 with different replicase proteins suggested viral protein-protein interaction, which may be key to understanding their functions and potential molecular mechanisms. Viral intermediate dsRNA was detected in perinuclear foci as early as 2-h postinfection, indicating the initiation of virus replication. With the passage of time, these perinuclear dsRNA foci became larger and brighter, and nearly all colocalized with N protein, consistent with viral growth over time. Thus, the development of these anti-nsp antibodies provides basic tools for the further study of replication and diagnosis of SARS-CoV-2.

The output characteristics of vertical cavity surface emitting lasers (VCSELs) arrays are largely influenced by temperature. We systematically studied thermal properties in 20-element oxide-confined VCSEL arrays via both theory and experiment. The output power, conversion efficiency, and threshold current dependent on ambient temperatures were measured. According to the relationship of wavelength shift and dissipated power, the device thermal resistance dependent on ambient temperature was obtained. The actual temperature in active region was successfully extracted. A 3-D heat diffusion model was established to simulate temperature distribution accurately.

A novel swine enteric alphacoronavirus, swine acute diarrhoea syndrome coronavirus (SADS-CoV), related to Rhinolophus bat CoV HKU2 in the subgenus Rhinacovirus emerged in southern China in 2017, causing diarrhoea in newborn piglets, and critical questions remain about the pathogenicity, cross-species transmission and potential animal reservoirs. Our laboratory's previous research has shown that SADS-CoV can replicate in various cell types from different species, including chickens. Here, we systematically explore the susceptibility of chickens to a cell-adapted SADS-CoV strain both in vitro and in vivo. First, evidence of SADS-CoV replication in primary chicken cells, including cytopathic effects, immunofluorescence staining, growth curves and structural protein expression, was proven. Furthermore, we observed that SADS-CoV replicated in chicken embryos without causing gross lesions and that experimental infection of chicks resulted in mild respiratory symptoms. More importantly, SADS-CoV shedding and viral distribution in the lungs, spleens, small intestines and large intestines of infected chickens were confirmed by quantitative reverse transcription polymerase chain reaction and immunohistochemistry. The genomic sequence of the original SADS-CoV from the pig source sample in 2017 was determined to have nine nucleotide differences compared to the cell-adapted strain used; among these were three nonsynonymous mutations in the spike gene. These results collectively demonstrate that chickens are susceptible to SADS-CoV infection, suggesting that they are a potential animal reservoir. To our knowledge, this study provides the first experimental evidence of cross-species infection in which a mammalian alphacoronavirus is able to infect an avian species.

Liquid hydrolysate (LH) derived from the microwave hydrothermal pretreatment (MHP) of wheat straw (WS) was anaerobically digested together with the solid residual to promote the overall energy profit. Different MHP temperatures (90, 120, 150, 180 °C) and retention times (10, 20, 40 min) were investigated. Increased MHP intensity generated plenty of VFAs (mainly acetate) and phenols in the LH, implying the double-side effect of LH on AD. The highest methane production of 227.92 mL CH

The particularity of the tumor microenvironment (TME) significantly limits the efficiency of chemodynamic therapy (CDT). Although various measures have been taken to improve the efficiency of CDT, how to organically integrate them into one nanosystem to achieve efficient synergy for CDT according to predetermined procedures is still an urgent problem to be solved. This work reported a multifunctional nanosystem, TP

The combined effects of liquid digestate recirculation (LDR) and biochar on methanogenesis and microbial communities were studied in semi-continuous anaerobic reactors fed with wheat straw and swine manure. The tolerated organic loading rate (OLR) was expanded from 5 g- volatile solids (VS)∙L

Device characterization

Oxidative stress underlies a number of pathological conditions, including cancer, neurodegeneration, and aging. Antioxidant-rich foods help maintain cellular redox homeostasis and mitigate oxidative stress, but the underlying mechanisms are not clear. For example, sulforaphane (SFN), an electrophilic compound that is enriched in cruciferous vegetables such as broccoli, is a potent inducer of cellular antioxidant responses. NFE2L2/NRF2 (nuclear factor, erythroid 2 like 2), a transcriptional factor that controls the expression of multiple detoxifying enzymes through antioxidant response elements (AREs), is a proposed target of SFN. NFE2L2/NRF2 is a target gene of TFEB (transcription factor EB), a master regulator of autophagic and lysosomal functions, which we show here to be potently activated by SFN. SFN induces TFEB nuclear translocation via a Ca(2+)-dependent but MTOR (mechanistic target of rapamycin kinase)-independent mechanism through a moderate increase in reactive oxygen species (ROS). Activated TFEB then boosts the expression of genes required for autophagosome and lysosome biogenesis, which are known to facilitate the clearance of damaged mitochondria. Notably, TFEB activity is required for SFN-induced protection against both acute oxidant bursts and chronic oxidative stress. Hence, by simultaneously activating macroautophagy/autophagy and detoxifying pathways, natural compound SFN may trigger a self-defense cellular mechanism that can effectively mitigate oxidative stress commonly associated with many metabolic and age-related diseases. Abbreviations: ANOVA: analyzes of variance; AREs: antioxidant response elements; Baf-A1: bafilomycin A(1); BHA: butylhydroxyanisole; CAT: catechin hydrate; CCCP: carbonyl cyanide m- chlorophenylhydrazone; CLEAR: coordinated lysosomal expression and regulation; DCFH-DA: 2ʹ,7ʹ-dichlorofluorescin diacetate; FBS: fetal bovine serum; GFP: green fluorescent protein; HMOX1/HO-1: heme oxygenase 1; KD: knockdown; KEAP1: kelch like ECH associated protein 1; KO: knockout; LAMP1: lysosomal associated membrane protein 1; MCOLN1/TRPML1: mucolipin 1; ML-SA1: mucolipin-specific synthetic agonist 1; ML-SI3: mucolipin-specific synthetic inhibitor 3; MTOR: mechanistic target of rapamycin kinase; MTORC1: mechanistic target of rapamycin kinase complex 1; NAC: N-acetylcysteine; NFE2L2/NRF2: nuclear factor: erythroid 2 like 2; NPC: Niemann–Pick type C; PBS: phosphate-buffered saline; PPP2/PP2A: protein phosphatase 2; Q-PCR: real time polymerase chain reaction; ROS: reactive oxygen species; RPS6KB1/S6K1/p70S6K: ribosomal protein S6 kinase B1; SFN: sulforaphane; TFEB: transcription factor EB; WT, wild-type

The 808-nm vertical cavity surface emitting laser (VCSEL) with strained In0.13Ga0.75Al0.12As/Al0.3Ga0.7As quantum wells is designed and fabricated. Compared with the VCSELs with Al0.05Ga0.95As/Al0.3Ga0.7As quantum wells, the VCSEL with strained In0.13Ga0.75Al0.12As/Al0.3Ga0.7As quantum wells is demonstrated to possess higher power conversion efficiency (PCE) and better temperature stability. The maximum PCE of 43.8% for 10-μm VCSEL is achieved at an ambient temperature of 30 °C. The size-dependent thermal characteristics are also analyzed by characterizing the spectral power and output power. It demonstrates that small oxide-aperture VCSELs are advantageous for temperature-stable performance.

Background & Objective: The lysosome is a membrane-enclosed organelle widely found in every eukaryotic cell. It has been deemed as the stomach of the cells. Recent studies revealed that it also functions as an intracellular calcium store and is a platform for nutrient-dependent signal transduction. Similar with the plasma membrane, the lysosome membrane is furnished with various proteins, including pumps, ion channels and transporters. So far, two types of lysosomal potassium channels have been identified: large-conductance and Ca2+-activated potassium channel (BK) and TMEM175. TMEM175 has been linked to several neurodegeneration diseases, such as the Alzheimer and Parkinson disease. Recent studies showed that TMEM175 is a lysosomal potassium channel with novel architecture and plays important roles in setting the lysosomal membrane potential and maintaining pH stability. TMEM175 deficiency leads to compromised lysosomal function, which might be responsible for the pathogenesis of related diseases. BK is a well-known potassium channel for its function on the plasma membrane. Studies from two independent groups revealed that functional BK channels are also expressed on the lysosomal plasma membrane. Dysfunction of BK causes impaired lysosomal calcium signaling and abnormal lipid accumulation, a featured phenotype of most lysosomal storage diseases (LSDs). Boosting BK activity could rescue the lipid accumulation in several LSD cell models. Overall, the lysosomal potassium channels are essential for the lysosome physiological function, including lysosomal calcium signaling and autophagy. The dysfunction of lysosomal potassium channels is related to some neurodegeneration disorders. Conclusion: Therefore, lysosomal potassium channels are suggested as potential targets for the intervention of lysosomal disorders.

O3-type transition metal oxides as the cathodes for Na-ion batteries have attracted extensive attention owing to their high theoretical specific capacity and ease of synthesis. This work indicates enhanced electrochemical reversibility and improved air stability via a rational Zn2+ doping for O3-NaNi0.5Mn0.5O2. It exhibits a discharge capacity of 113 mAh g−1 at 0.5 C, excellent capacity retention of 80% after 150 cycles, and the capability to release a capacity of 82 mAh g−1 at 5 C in the voltage range of 2–4 V. The doped cathode undergoes a phase transition of O3-O3/O′3-P3-P′3-O''3 with a small volume change of approximately 2.00% in the voltage range of 2–4 V, and a subsequent slight structural change in the high voltage range of 4–4.2 V, which well demonstrates the enhanced cyclic stability. The assembled full cell confirms the feasibility of applying O3-type NaNi0.47Zn0.03Mn0.5O2 cathode for Na-ion batteries. Thus, the work suggests an efficient strategy to better release the potential of high-energy cathode for Na-ion batteries.

Methyl glyoxal (MG), a major precursor of advanced glycation end-products, has been identified as significant in the progression of several diseases including aging, diabetes and neurodegenerative diseases as well as causing hepatic damages. 7-hydroxycoumarin (7-HC), a natural-occurring derivative of coumarin from fruits and plants, has been reported to exert antioxidant and free radical-scavenging properties, protecting cells from aldehydes and oxidants. In this study, the ability of 7-HC to protect human HepG2 cells against MG-induced toxicity and oxidative stress was investigated. Results show that 7-HC pretreatment significantly attenuates MG-induced cytotoxicity, apoptotic changes and ROS accumulation and that this protection is shown to be associated with the induction of the nuclear factor erythroid 2-related factor 2 (NRF2) and its downstream detoxifying enzymes. In response to 7-HC, NRF2 protein translocates from cytosol to the nuclei. In addition, depletion of NRF2 by siRNA significantly reduces the protective effect of 7-HC against MG, suggesting that NRF2 plays an important role in the protective function of 7-HC. These findings highlight the potential for the interventional activation of the NRF2 induction via the non-toxic natural phytochemical 7-HC as a novel therapeutic approach towards the detoxification of MG, with the aim of halting the progression of diseases in which MG has been implicated.

We have investigated the dry etching of Al0.12GaAs/Al0.9GaAs Distributed Bragg Reflectors (DBRs) using photoresist mask in Inductively Coupled Plasma system with Cl2/BCl3/Ar chemistry. Resultant etch rate/etch profiles are studied as a function of ICP process parameters and photoresist mask sidewall profile. The vertical and inclined sidewalls were obtained via controlling mixing gas proportion. Enhancing physical effect in etching, photoresist mask patterns could transfer to etched substrate. In the end, controllable sidewall profile, smooth etch surface and repeatable process of Al0.12GaAs/Al0.9GaAs DBRs etching were achieved.

Graphical abstract, Highlights • A summary of the effects of lysosomal ion channels on the cellular entry and uncoating of enveloped viruses. • Lysosomal channels represent an exciting and emerging target for therapeutic strategies against enveloped viruses. • Further investigation may aid in development of novel therapies against SARS-CoV-2., Ion channels are necessary for correct lysosomal function including degradation of cargoes originating from endocytosis. Almost all enveloped viruses, including coronaviruses (CoVs), enter host cells via endocytosis, and do not escape endosomal compartments into the cytoplasm (via fusion with the endolysosomal membrane) unless the virus-encoded envelope proteins are cleaved by lysosomal proteases. With the ongoing outbreak of severe acute respiratory syndrome (SARS)-CoV-2, endolysosomal two-pore channels represent an exciting and emerging target for antiviral therapies. This review focuses on the latest knowledge of the effects of lysosomal ion channels on the cellular entry and uncoating of enveloped viruses, which may aid in development of novel therapies against emerging infectious diseases such as SARS-CoV-2.

Cells utilize calcium ions (Ca2+) to signal almost all aspects of cellular life, ranging from cell proliferation to cell death, in a spatially and temporally regulated manner. A key aspect of this regulation is the compartmentalization of Ca2+ in various cytoplasmic organelles that act as intracellular Ca2+ stores. Whereas Ca2+ release from the large-volume Ca2+ stores, such as the endoplasmic reticulum (ER) and Golgi apparatus, are preferred for signal transduction, Ca2+ release from the small-volume individual vesicular stores that are dispersed throughout the cell, such as lysosomes, may be more useful in local regulation, such as membrane fusion and individualized vesicular movements. Conceivably, these two types of Ca2+ stores may be established, maintained or refilled via distinct mechanisms. ER stores are refilled through sustained Ca2+ influx at ER-plasma membrane (PM) membrane contact sites (MCSs). In this review, we discuss the release and refilling mechanisms of intracellular small vesicular Ca2+ stores, with a special focus on lysosomes. Recent imaging studies of Ca2+ release and organelle MCSs suggest that Ca2+ exchange may occur between two types of stores, such that the small stores acquire Ca2+ from the large stores via ER-vesicle MCSs. Hence vesicular stores like lysosomes may be viewed as secondary Ca2+ stores in the cell.