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The simultaneous downstream valorization of cellulose and lignin is an important aspect of efficiently extracting value from lignocellulose. The present work, we demonstrated the preparation of a novel bio-based filler by the co-assembly of cellulose and lignin obtained from a one-pot ethanosolv lignocellulose fractionation process. The cellulose was valorized by forming cellulose nanocrystals (CNCs) through simple bleaching and ultrasonication processes. The lignin fractions demonstrated greater solubility (19.2 mg/mL) and lower molecular weight (6980 g/mol) than conventional industrial lignins. Various lignin@CNCs specimens were prepared via a facile co-assembly of the lignin and CNCs. These entirely bio-based materials could be used as a multifunctional filler to enhance the properties of a waterborne coating (WBC). Specifically, the mechanical properties, coating performance and ultraviolet resistance of a WBC were all significantly improved, demonstrating a synergistic enhancement effect obtained from the CNCs and lignin. In this manner, both cellulose and lignin components were efficiently transformed to value-added fillers for WBC, demonstrating a highly efficient pathway for lignocellulose utilization and downstream value-added applications.

A new Cd(ii) MOF with fsh topology was synthesized and used as a photocatalyst for the safe degradation of dyes.

Huanglongbing (HLB), or citrus greening disease, has complex and variable symptoms, making its diagnosis almost entirely reliant on subjective experience, which results in a low diagnosis efficiency. To overcome this problem, we constructed and validated a deep learning (DL)-based method for detecting citrus HLB using YOLOv5l from digital images. Three models (Yolov5l-HLB1, Yolov5l-HLB2, and Yolov5l-HLB3) were developed using images of healthy and symptomatic citrus leaves acquired under a range of imaging conditions. The micro F1-scores of the Yolov5l-HLB2 model (85.19%) recognising five HLB symptoms (blotchy mottling, “red-nose” fruits, zinc-deficiency, vein yellowing, and uniform yellowing) in the images were higher than those of the other two models. The generalisation performance of Yolov5l-HLB2 was tested using test set images acquired under two photographic conditions (conditions B and C) that were different from that of the model training set condition (condition A). The results suggested that this model performed well at recognising the five HLB symptom images acquired under both conditions B and C, and yielded a micro F1-score of 84.64% and 85.84%, respectively. In addition, the detection performance of the Yolov5l-HLB2 model was better for experienced users than for inexperienced users. The PCR-positive rate of Candidatus Liberibacter asiaticus (CLas) detection (the causative pathogen for HLB) in the samples with five HLB symptoms as classified using the Yolov5l-HLB2 model was also compared with manual classification by experts. This indicated that the model can be employed as a preliminary screening tool before the collection of field samples for subsequent PCR testing. We also developed the ‘HLBdetector’ app using the Yolov5l-HLB2 model, which allows farmers to complete HLB detection in seconds with only a mobile phone terminal and without expert guidance. Overall, we successfully constructed a reliable automatic HLB identification model and developed the user-friendly ‘HLBdetector’ app, facilitating the prevention and timely control of HLB transmission in citrus orchards.

Simulating the comprehensive functions of native skin—and not simply the perception of external physical stimuli—by electronic skin (e-skin) has gathered increasing attention in the development of wearable devices and human-interactive technology. Here, we report an anti-bacterial, color-variable, ultraviolet (UV)-sensitive, shape-adaptive, and immunoregulatory e-skin based on a single- and dual-network switchable hydrogel composed of a covalent network of polyacrylamide (PAAm) and a coordinated network of xanthan gum (Xg)/iron ions [Fe(III)]. In the presence of sodium lactate and UV exposure, Fe(III) could be reduced to Fe(II), which de-coordinated the Xg/Fe(III) network. During this reduction process, the e-skin realized three functions of real skin: (i) UV triggered a color change with detectable resistance alterations; (ii) reactive oxygen species (ROS) were dramatically produced to defend against pathogens; and (iii) the piezoresistant hydrogel became highly stretchable to perceive all-scale human motions. Moreover, the shear-thinning properties of Xg in the precursor solution allowed the e-skin to be printable, and the anti-inflammatory functions of de-coordinated Xg were beneficial for wound healing. In summary, this newly-developed e-skin can achieve the perception of UV and human motions. It has promising applications for irregularly-shaped body surfaces and infected wounds.

Positively charged cationic defects are the main source of defects in metal-halide perovskite solar cells. They determine the quasi-Fermi level of electrons under illumination and contribute to non-radiative recombination loss, causing an open-circuit voltage deficit. In addition, they act as ion migration pathways for halide hopping, thus deteriorating long-term stability. Herein, a nitrogen-donor crown ether as a positive defect passivator is developed, which demonstrates a soft Lewis base nature, a large donor number and a higher formation constant with positively charged cationic defects. Density functional theory calculation indicates that the electron-donating nitrogen atom dramatically increases the electron density of oxygen atoms, leading to a strong affinity with positively charged cationic defects (Pb2+ and Cs+). The electron trap density in perovskite is significantly reduced by 27 %, resulting in an increased build-in potential. By adding a small amount of nitrogen-donor crown ether to the precursor solution, the perovskite solar cells achieve an efficiency of 24.07 % with an open-circuit voltage of 1.174 V and a fill factor of 82.15 %. Moreover, the unencapsulated perovskite solar cells show a T80 lifetime of 510 h under continuous operation (1 sun equivalent illumination, maximum power point tracking condition, dry N2 atmosphere), and enhanced moisture and heat stability.

Plutella xylostella is a typical phototactic pest. LW-opsin contributes to the phototaxis of P. xylostella, but the expression changes of other genes in the phototransduction pathway caused by the mutation of LW-opsin remain unknown. In the study, the head transcriptomes of male G88 and LW-opsin mutants were compared. A GO-function annotation showed that DEGs mainly belonged to the categories of molecular functions, biological processes, and cell composition. Additionally, a KEGG-pathway analysis suggested that DEGs were significantly enriched in some classical pathways, such as the phototransduction-fly and vitamin digestion and absorption pathways. The mRNA expressions of genes in the phototransduction-fly pathway, such as Gq, ninaC, and rdgC were significantly up-regulated, and trp, trpl, inaD, cry1, ninaA and arr1 were significantly down-regulated. The expression trends of nine DEGs in the phototransduction pathway confirmed by a RT-qPCR were consistent with transcriptomic data. In addition, the influence of a cry1 mutation on the phototaxis of P. xylostella was examined, and the results showed that the male cry1 mutant exhibited higher phototactic rates to UV and blue lights than the male G88. Our results indicated that the LW-opsin mutation changed the expression of genes in the phototransduction pathway, and the mutation of cry1 enhanced the phototaxis of a P. xylostella male, providing a basis for further investigation on the phototransduction pathway in P. xylostella.

In December 2019, the COVID-19 pandemic began to ravage the world quickly, causing unprecedented losses in human life and the economy. A statistical study revealed that the proportion of solid organ transplant (SOT) recipients with severe symptoms and deaths after being infected by SARS-CoV-2 is considerably higher than that of non-SOT recipients, and the prognosis is relatively poor. In addition, the clinical manifestation of SOT recipients suffering from COVID-19 is different from that of general COVID-19 patients. Acute kidney injury (AKI) is a common complication in COVID-19 patients, and it is likely more common among SOT recipients infected with SARS-CoV-2. Clinical experts consider that SOT recipients have long-term treatment with immunosuppressants, and the comorbidities are driven by a high rate of severe symptoms and mortality. Orthotopic kidney allograft transplantation is an effective treatment for patients suffering from end-stage kidney disease/kidney failure through which they can easily extend their life. Indeed, kidney transplant recipients have suffered significant damage during this pandemic. To effectively reduce the severity of symptoms and mortality of kidney transplant recipients suffering from COVID-19, precise application of various drugs, particularly immunosuppressants, is necessary. Therefore, herein, we will collate the current clinical experience of treating COVID-19 infection in kidney transplant recipients and discuss the adjustment of patients using immunosuppressive agents in the face of COVID-19.

In order to break through the limitations of wood solar drying and its application in the tropics, the core part of a wood solar drying system (collection/storage media) should be adapted to the se...

Zero-thermal-expansion (ZTE) alloys, as dimensionally stable materials, are urgently required in many fields, particularly in highly advanced modern industries. In this study, high-performance ZTE with a negligible coefficient of thermal expansion a

Nanostructured fluoridated hydroxyapatite (FHA) coatings were deposited on Ti substrates using the suspension plasma spraying (SPS) process. The effects of the plasma spraying power on the microstructure and properties of coatings were intensively studied. The X-ray diffraction pattern showed that the as-sprayed coatings mainly consisted of the hydroxyapatite (HA) phase, and the crystal size was estimated to be dozens of nanometers. With the increase of the spraying power, the amount of decomposed phases, crystallinity, and crystal size increased. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy confirmed the presence of fluorine in the as-sprayed coatings. The corrosion in simulated body fluid (SBF) was studied using potentiodynamic polarization tests, and the results indicated that the coating greatly enhanced the corrosion resistance of the Ti substrate. The chemical stability was assessed by measuring the weight loss of the coatings before and after immersion in a citric acid-modified phosphate buffered saline (PBS) solution at various intervals. The results showed that increasing the spraying powers decreased the dissolution rate of coatings. The in vitro bioactivity was characterized by soaking coatings in the SBF solution for different times, and the obtained results suggested that the spraying power levels affected the initial nucleation rate of the bone-like apatite on the coating surface. The antibacterial activity was investigated using optical density (OD) growth curves and colony-forming unit assays. The coating prepared at a low spraying power had relatively high antibacterial activity with respect to Staphylococcus aureus.

Lipid droplet (LD) is a monolayer phospholipid membrane-bound organelle found in all eukaryotes and several prokaryotes which plays key roles in cellular lipid homeostasis and human health. The origin and evolution of the organelle remains unknown. Here, we report that through screening over 660 bacteria using biophysical and biochemical methods, plus LD isolation and proteomic tool, LDs were identified in most of these microbes, affiliated with five main bacterial phyla. Moreover, LDs were also identified in E. coli overexpressing lipid synthesis enzymes, indicating that bacteria without detectable LDs possessed the ability of LD biogenesis. The similarity of isolated LDs from representative strains and evolutionary analysis of LD major protein PspA demonstrate that LDs were conserved in bacteria. Furthermore, time-lapse imaging revealed that LDs were inheritable accompanying with bacterial growth and division. Finally, a common ancestor of LD-containing bacteria was predicted to originate 3.19 billion years ago by a phylogenetic analysis. Our findings suggest that LD is a widespread and inheritable organelle from an ancient common ancestor.

The Sm8Co73.2Fe8.8B10 ribbons were prepared by melt-spinning at a roller velocity of 40 m/s followed by annealing at 700–900 °C for 30 min, and then their structure and magnetic properties were studied. The results show that the as-spun ribbons are composed of Sm(Co,Fe)12B6 and Sm2(Co,Fe)14B nanocrystallines with an average size of ∼10 nm distributed on the amorphous matrix, and exhibit the weak hard magnetic properties. Moreover, the annealing treatment at 800 °C can obviously improve the ones, and make the ribbons consist of Sm(Co,Fe)12B6, Sm2(Co,Fe)14B, Sm2(Co,Fe)7, Co0.72Fe0.28 and a little residual amorphous phase. However, a higher annealing temperature of 900 °C will reduce the comprehensive magnetic properties of ribbons due to the changes in microstructure. The Curie temperatures of Sm(Co,Fe)12B6, Sm2(Co,Fe)14B, Co0.72Fe0.28 phases are -(103–120) °C, 770–780 °C and 900 °C, respectively. The relationship between microstructure and magnetic properties was discussed in detail and the microstructural model was proposed to determine the magnetic properties.

The SmCo3.1−xFe0.9CuxB (x = 0, 0.02, 0.06 and 0.1) ribbons were prepared by melt-spinning at 40 m/s accompanied by annealing at 800 °C for 30 min, and then their structures and magnetic properties were investigated. The results show that the annealed ribbons are composed of single Sm(Co,Fe)4B phase at x = 0, and single Sm(Co,Fe,Cu)4B phase at x = 0.02–0.1. These phases with different Cu contents have the same hexagonal CeCo4B-type structure with a space group of P6/mmm, and the lattice parameters a and c increase monotonically with increasing x from 0 to 0.1, while the axial ratio of c/a remains almost unchanged (c/a = 1.3495). In particular, the x = 0.06 ribbons consisting of short rod-shaped Sm(Co,Fe,Cu)4B grains, which contact with each other directly, show the high coercivity of up to 44450.0 Oe, and each in-plane grain exhibits preferred orientation along its long or short axis direction.

The phase compositions, atomic structures and magnetic properties of as-spun SmCo4B and SmCo3.1Fe0.9B ribbons are comparatively studied. It was found that SmCo4B and SmCo3.1Fe0.9B ribbons consist of single SmCo4B or Sm(Co,Fe)4B phase, respectively. The SmCo4B phase displays homogeneous equiaxed grains, which contact each other directly, while Sm(Co,Fe)4B phase does not expose its clear grain profile. The Extended X-ray Absorption Fine Structure (EXAFS) analysis shows that both interatomic distance and disorder degree increase when a part of Co is substituted by Fe in SmCo4B ribbons. Such change in atomic structure increases the effect of atomic mismatch and the glass-forming ability of SmCo4B ribbons, but reduces the magnetocrystalline anisotropy. Annealing is quite helpful to improve the magnetic properties of SmCo3.1Fe0.9B ribbons.

A new Sm(Co,Fe,Cu)4B/Sm2(Co,Fe,Cu)7 cell structure is found, and its phase composition, microstructure and magnetic properties are investigated. Particularly, the atom structure of main phase is analyzed by extended X-ray absorption fine structure. It was found that as-spun SmCo2.94FeCu0.06B ribbons were composed of amorphous phase and approximate equiaxed Sm(Co,Fe,Cu)4B nanocrystallines. The high disorder of the nanocrystallines leads to the low magnetic anisotropy. After the as-spun ribbons were annealed at 800 °C for 30 min, the amorphous phase disappeared completely. The short rod-shaped Sm(Co,Fe,Cu)4B grains have a staggered distribution accompanied by ∼8 vol% lamellar Sm2(Co,Fe,Cu)7 phase at grain boundaries, and the new cell/cell-wall-type Sm(Co,Fe,Cu)4B/Sm2(Co,Fe,Cu)7 microstructure is produced. The annealed ribbons show an ultra-high coercivity of up to 5.01 T at room temperature, 40.64 T at 5 K (obtained by extrapolating), and estimated to be ∼ 41.96 T at 0 K. The microstructureal models of both ribbons are created and the coercivity mechanism is discussed in detail.