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α-Alumina (α-Al 2 O 3), widely used as a raw material or production in advanced manufacturing industry, has attracted much attention in terms of its preparation temperature. A simple dissolution-evaporation-precipitation process was employed to obtain the amorphous Al-oxalate (AAO) precursor, serving as the starting material for the low temperature preparation of nano α-Al 2 O 3. The crystalline structure and thermal behavior of the AAO were compared with commercially available aluminum hydroxide (Al(OH) 3) powder using the X-ray powder diffraction (XRD) instrument, the thermal gravity analysis and differential scanning calorimetry (TG-DSC). The phase transition mechanism of AAO was investigated by the fourier transform infrared spectroscopy (FTIR), transmission electron microscope (TEM), scanning electron microscope (SEM), and 27Al magic angle spinning nuclear magnetic resonance (27Al-MAS-NMR). The DSC results indicated that AAO underwent a phase transformation at 982 °C. The α-alumina diffraction peaks appeared in AAO at 1000 °C, while α-Al 2 O 3 phase was observed for Al(OH) 3 at 1200 °C. Furthermore, an absorption peak at 452 cm−1, corresponding to Al–O bond in α-alumina was detected at 1000 °C. The proposed low-temperature preparation mechanism of α-alumina from AAO is as follows: four coordination Al-oxalate species entities coexist within the AAO sample; with increasing temperature, organic acid functional groups oxidize and volatilize, resulting in the formation of tetra-coordinate [AlO 4 ], penta-coordinate [AlO 5 ], and hexa-coordinate [AlO 6 ] atomic groups; these atomic clusters further polymerize to form a structurally dense α-alumina crystal at the nano-scale (∼50 nm) at around 1000 °C. The experimental findings present a novel approach and method for the low-temperature preparation of nano-sized alumina powder. Additionally, a feasible theoretical reference for the low-temperature phase transition mechanism of amorphous Al-oxalate was provided. [ABSTRACT FROM AUTHOR]

Femoral head necrosis (FHN) in broilers is a common leg disorder in intensive poultry farming, giving rise to poor animal health and welfare. Abnormal mechanical stress in the hip joint is a risk factor for FHN, and articular cartilage is attracting increasing attention as a cushion and lubrication structure for the joint. In the present study, broilers aged 3 to 4 wk with FHN were divided into femoral head separation (FHS) and femoral head separation with growth plate lacerations (FHSL) groups, with normal broilers as control. The features of the hip joint, bone, and cartilage were assessed in FHN progression using devices including computed tomography (CT), atomic force microscope (AFM), and transmission electron microscopy (TEM). Broilers with FHN demonstrated decreased bone mechanical properties, narrow joint space, and thickened femoral head stellate structures. Notably, abnormal cartilage morphology was observed in FHN-affected broilers, characterized by increased cartilage thickness and rough cartilage surfaces. In addition, as FHN developed, cartilage surface friction and friction coefficient dramatically increased, while cartilage modulus and stiffness decreased. The ultramicro-damage occurred in chondrocytes and the extracellular matrix (ECM) of cartilage. Cell disintegration, abnormal mitochondrial accumulation, and oxidative stress damage were observed in chondrocytes. A notable decline in cartilage collagen content was observed in ECM during the initial stages of FHN, accompanied by a pronounced reduction in collagen fiber diameter and proteoglycan content as FHN progressed. Furthermore, the noticeable loosening of the collagen fiber structure and the appearance of type I collagen were noted in cartilage. In conclusion, there was a progressive decrease in bone quality and multifaceted damage of cartilage in the femoral head, which was closely linked to the severity of FHN in broilers. [ABSTRACT FROM AUTHOR]

Although mammalian kidney regeneration has been reported to occur throughout life, mature kidneys in mammals are not thought to regenerate sufficiently, particularly glomeruli. In our previous work, we found that renal regeneration could be enhanced by decellularized renal scaffolds after partial nephrectomy. In this study, we verified that the enhanced renal regeneration mediated by decellularized scaffolds could be attributed to regenerated glomeruli, which were counted both indirectly and directly under a microscope. Using the isobaric tag for relative and absolute quantitation, we performed proteomics analysis and found that hypoxia-inducible factor (HIF)-1α may be a key factor involved in induced renal regeneration. Dimethyloxyallyl glycine (DMOG), a propyl hydroxylase inhibitor, was applied to stabilize constitutive expression of HIF-1α protein, and small interfering RNA was used to inhibit gene expression. Administration of DMOG to decellularized scaffold-grafted rats improved the induced renal regeneration, whereas si Hif1α transfection decreased the regeneration capacity. These findings revealed the critical role of HIF-1α in renal regeneration and provided important insights into our understanding of kidney development and the treatment of various kidney diseases. [ABSTRACT FROM AUTHOR]

A promising paradigm to regenerative medicine involves the application of biomaterials, which makes a spurt of progress in the past 20 years. Of various biomaterials, decellularized biomaterials possess good biocompatibility and great potential for clinical translation. The role of decellularized biomaterials in tissue repair and regeneration is not just the structure and delivering bioactive matters, what's even important, the interaction between biomaterials and the internal environment, especially the scaffold-immune system interactions, which is the initial response to in vivo implantation. Consequently, we have reviewed the immunogenicity of decellularized scaffolds derived from various tissues and organs, and immunomodulatory effects of decellularized scaffolds in the view of innate and adaptive immune systems. Finally, we discuss the influence factors of host responses mediated by decellularized biomaterials. Decellularized scaffold-immune interactions can provide important mechanistic insight into the development of decellularized materials in vivo , penetrating into the knowledge is the necessary precondition for the clinical translation. [ABSTRACT FROM AUTHOR]

Recently, great efforts have been devoted to the production of higher alcohols (C 2+ alcohols) by chemical synthesis, but it's still quite challenging for the related heterogeneous catalysis. In this work, the hydrogenolysis of sugar alcohols derived from biomass was proposed to efficiently synthesize higher alcohols over the Ru-Mo/CMK-3 catalyst. The C C and C O bonds in sorbitol were positively broken to form C 2+ alcohols, while the excessive cleavage of C O bonds to form C1–C6 alkanes was effectively suppressed. The experimental results indicated that the yield of C 2+ alcohols in the products reached 49.0%, and that of C 5+ alcohols reached 29.9% in a continuous flow reactor. Preliminary experimental results and catalyst characterization supported that the synergetic effect of Ru and Mo species, different Ru precursors and the mesoporous channel effect of CMK-3 carrier were the key to such high reactivity. Unlabelled Image • Higher alcohols were produced efficiently from sorbitol over Ru-Mo/CMK-3 catalyst. • Yield of C 2+ alcohols reached 49.0%, hereinto yield of C 5+ alcohols reached 29.9%. • Ru precursors and the mesoporous channel effect of CMK-3 carrier inhibited the deep HDO of sorbitol. • Synergetic effect of Ru and Mo species was the key to HDO of sorbitol. [ABSTRACT FROM AUTHOR]

Leg disorders frequently occur in fast-growing broiler chickens, constituting severe health and welfare problems. Although salidroside (SAL) promotes osteogenesis and inhibits apoptosis of chondrocytes in rats, it remains to be determined whether SAL can effectively improve bone growth in broilers. The present study was designed to investigate the effects of dietary SAL supplementation on bone and cartilage characteristics in broiler chickens. Ninety-six Arbor Acres broiler chickens were randomly divided into 4 groups: control, low-dose SAL, medium-dose SAL, and high-dose SAL groups. The broiler chickens were raised until 42 d of age, with samples of bone and cartilage collected for biomechanical testing and bone metabolism index detection. The results showed that SAL significantly increased the vertical external diameter, cross-sectional moment of inertia, and cross-sectional area of the femur and tibia. Additionally, SAL enhanced bone mineral density and strength, as evidenced by significant increases in stiffness, Young's modulus, ultimate load, and fracture work of the femur and tibia. Furthermore, SAL influenced the relative content of phosphate, carbonate, and amide I in cortical bone. Moreover, SAL upregulated the expression of osteogenic genes (Collagen-1, RUNX2, BMP2, and ALP) in a dose-dependent manner and maintained the homeostasis of the extracellular matrix (ECM) of chondrocytes. These results indicated that SAL promoted leg health in broilers by improving bone and cartilage quality and enhancing chondrocyte activity. [ABSTRACT FROM AUTHOR]

• Using multiple groups of magnet coupling and plucking harvesters driven by inertial wheel. • In contrast to previous study, we have made a parametric study of the piezoelectric energy harvester structure. • It can generate milliwatt-level electrical energy at a smaller resonance frequency. Piezoelectric technology has attracted extensive attention and played an increasingly important role in the aspect of harvesting energy from the environment, which has advantages of simple structure, good performance, and so on. In this study, a multi-group dual piezoelectric energy harvester driven by inertial wheel with magnet coupling and plucking (M−PEH) is proposed. The M−PEH mainly includes a base, supports, piezoelectric patches, magnets, magnets cover, and rotor. This paper studies the series–parallel connection relationship between the circular and rectangular piezoelectric patches in the circumferential direction of the base, and the influence on the peak-to peak voltage when the length of the magnet extending from the surface of the rotor is different. Under the condition of inertial wheel 407 g, the M−PEH is tested and researched from 50 r/min to 600 r/min. After a series of experimental studies at 550 r/min, the peak-to-peak voltages of the circular and rectangular piezoelectric patches are respectively 15.00 V, 28.74 V, and 34.37 V, 67.19 V in the case of parallel and series connection when the length of the magnet protruding from the surface of the rotator is 7 mm. Besides that, under the condition of series connection, it is shown that the root-mean-square voltage and power of the circular and rectangular piezoelectric patches are 3.37 V, 0.054 mW, and 10.03 V, 0.80 mW, respectively at 550 r/min when the resistance is 100 kΩ. It can also easily light 47 light-emitting diodes (LEDs) under the excitation of 550 r/min. Therefore, the M−PEH can effectively collect energy under the drive of the inertia wheel and power the microelectronic devices. [ABSTRACT FROM AUTHOR]