Role of Autophagy in Burn Wound Progression and Wound Healing

Background: Burn wound progression refers to the phenomenon of continued tissue loss following abatement of an initial thermal insult, which makes the treatment more difficult, prolongs hospital stay, increases medical costs, and raises the likelihood of scar formation. Autophagy is a highly conserved pathway that delivers intracellular macromolecule waste to lysosomes, where they are degraded into biologically active monomers, such as amino acids, that are subsequently reused to maintain cellular metabolic turnover and homeostasis. We aimed to observe the expression of autophagy in burn wounds in a deep second‐degree rodent burn model and further investigate the role of autophagy on burn wound progression and wound healing

Sirt3 Ameliorates Oxidative Stress and Mitochondrial Dysfunction After Intracerebral Hemorrhage in Diabetic Rats

Aim: Sirtuin3 (sirt3) plays a pivotal role in improving oxidative stress and mitochondrial dysfunction which directly induced neuronal apoptosis after intracerebral hemorrhage (ICH). Reactive oxygen species (ROS) is also a critical activator in triggering NACHT, LRR, and PYD domains-containing protein 3 (NLRP3) inflammasomes activation which can regulate inflammatory responses in brain. Moreover, hyperglycemia can aggravate the ICH-induced damage. Hence, this study was designed to investigate the mechanisms of neuroprotection of sirt3 in hyperglycemic ICH.Methods: ICH model was established by autologous blood injection. Hyperglycemia was induced by intraperitoneal injection with streptozotocin. Honokiol (HKL, a pharmacological agonist of sirt3) was injected intraperitoneally at doses of 2.5, 5, or 10 mg/kg. Sirt3 small interfering RNA transfection was implemented through intracerebroventricular injection. The expression of sirt3 and its downstream signaling molecules were detected using Western blotting or immunofluorescence staining. Morphological changes of mitochondria were detected by electron microscopy. SH-SY5Y cells were incubated with 10 μM oxyhemoglobin for 48 h to establish an in vitro ICH model, and then JC-1 staining was used to determine mitochondrial membrane potential (Δψm).Results: Hyperglycemia could suppress sirt3 expression after ICH when compared with non-diabetic rats. Sirt3 protein expression was decreased to the minimum at 24 h in perihematoma tissues. Electron microscope analysis indicated that hyperglycemic ICH induced extensive mitochondrial vacuolization. HKL attenuated ROS accumulation, adenosine triphosphate reduction, and Δψm through Sirt3–superoxide dismutase 2 (SOD2) and Sirt3–NRF1–TFAM pathway. Sirt3 knockdown could exacerbate the neuronal apoptosis and reverse the positive effects of HKL. Sirt3 activation could decrease NLRP3 and interleukin-1β levels through deacetylating SOD2 and scavenging ROS.Conclusion: HKL protects against hyperglycemic ICH-induced neuronal injury via a sirt3-dependent manner

Study on Acoustic Features of Laying Hens’ Vocalization

International audienceIn this paper, vocalizations of laying hens (Hyline Brown) were focused. An experiment was designed to obtain acoustic features of laying hens with different ages: 35days-old, 95days-old and 125days-old. Vocalizations were recorded by the microphone MPA201. Analysis was done by some analytical software in order to gain time-domain features and frequency-domain properties of laying hens’ sound. The duration time, pitch frequency, formant track and spectrums of vocalizations were all included. Results showed that some characteristics of vocalizations of laying hens with different ages were dissimilar when under given state. It was proved that the vocalization of laying hens could be recognized and identified

Adsorption and Sensing Properties of Formaldehyde on Chemically Modified Graphene Surfaces

Chemically modifying graphene (such as chemical doping) is a commonly used method to improve its formaldehyde sensing properties, but the microscopic mechanisms of heteroatoms in the adsorption and sensing process are still unclear. In this paper, the adsorption and sensing properties of formaldehyde on graphene surfaces modified by X doping (X = B, N, O, P, S, Mg and Al) were systematically investigated by first-principles calculations. The adsorption geometries, adsorption energies, charge transfers, and electronic structures were obtained and analyzed. The adsorption strengths of HCHO molecule on the Mg- and Al-doped graphene surfaces were stronger than those of non-metal (B, N, O, P and S)-doped cases. These results showed that the Mg- or Al-doped graphene was better for HCHO detecting than the non-metal-doped graphene systems. The sensing properties were simulated by theNEGF method for the two-probe nano-sensors constructed from Al- and Mg-doped graphene. The maximum sensing responses of nano-sensors based on Al- and Mg-doped graphene were obtained to be 107% and 60%, respectively. The present study supplies a theoretical basis for designing superior graphene-based HCHO gas sensors

Adsorption and Sensing Properties of Formaldehyde on Chemically Modified Graphene Surfaces

Chemically modifying graphene (such as chemical doping) is a commonly used method to improve its formaldehyde sensing properties, but the microscopic mechanisms of heteroatoms in the adsorption and sensing process are still unclear. In this paper, the adsorption and sensing properties of formaldehyde on graphene surfaces modified by X doping (X = B, N, O, P, S, Mg and Al) were systematically investigated by first-principles calculations. The adsorption geometries, adsorption energies, charge transfers, and electronic structures were obtained and analyzed. The adsorption strengths of HCHO molecule on the Mg- and Al-doped graphene surfaces were stronger than those of non-metal (B, N, O, P and S)-doped cases. These results showed that the Mg- or Al-doped graphene was better for HCHO detecting than the non-metal-doped graphene systems. The sensing properties were simulated by theNEGF method for the two-probe nano-sensors constructed from Al- and Mg-doped graphene. The maximum sensing responses of nano-sensors based on Al- and Mg-doped graphene were obtained to be 107% and 60%, respectively. The present study supplies a theoretical basis for designing superior graphene-based HCHO gas sensors

Quantitative evaluation of the decarburization and microstructure evolution of WC–Co during plasma spraying

The major hurdle that limits extensive application of thermal sprayed WC–Co coatings is the undesirable phase changes from WC to W2C or even W due to loss of carbon. This study investigated quantitatively the decarburization of WC in both in-flight and coating formation stages during atmospheric plasma spraying. The microstructure evolution of WC particles accompanying the decarburization was also investigated. Results showed that decomposition and oxidation of WC to W2C predominantly occurred in the in-flight stage (75.82%), while remnant 24.18% occurred during the coating formation stage. Further carbon loss during the coating formation stage of WC–Co droplets is dependent significantly on the temperature of the substrate/pre-coating. Most of the irregular WC particles turned into rounded morphology with a significant decrease in size. W2C precipitated from the liquid matrix showed either columnar growth or epitaxial growth on WC substrate

Research on the evolution mechanism of pinned particles in welding HAZ of Mg treated shipbuilding steel

The large heat input welding performance of shipbuilding steel could be improved effectively by Mg treated in steelmaking process, but the mechanism of Mg on the nano-scale pinned particles had not been figured out yet, and this is also the bottleneck for Mg oxide metallurgy developing. In this research, with Mg-treated shipbuilding steel produced by industrial trials, the systematic experiments and theoretical analysis of thermodynamics and crystallography had been done. The results showed that, with increased welding energy, as the core pinned particles, the quantity of particles between 40 nm and 120 nm was stable when the welding energy was \u3c250 kJ/cm. During welding process, a number of reversible chemical reactions involving [Mg] and MgO generation or consumption occurred in the heat affect zone for Mg treated shipbuilding steel, and the temperature for more MgO formation just meet the thermodynamic conditions that the solid solution behavior of pinned particles TiN started to accelerate. Due to the extremely low disregistry value between MgO and TiN, the newly generated MgO which was determined by the [Mg] content in steel was highly likely to precipitate on the original TiN particles, delayed the solid solution of TiN, and generated more stable pinned particles

Controlled growth of bismuth antimony telluride BixSb2 − xTe3 nanoplatelets and their bulk thermoelectric nanocomposites

Solution synthesis as a scalable bottom-up growth method shows considerable advantages for designing novel nanostructured bulk composites with augmented thermoelectric performance. Tuning the composition of synthesized materials in the solution process is important for adjusting the carrier type and concentration. Here, we report a modified solvothermal synthesis method for the controlled growth of BixSb2−xTe3 nanoplatelets, which can be sintered into nanostructured bulk pellets by using the spark plasma sintering process. We further demonstrate the tuning of the stoichiometric composition in ternary BixSb2−xTe3 nanoplatelets with high crystallinity and homogenous phase purity, which is proved by X-ray diffraction and Raman spectroscopy. The composition dependence of the thermoelectric performance of p-type BixSb2−xTe3 pellets is also systemically studied. The optimized nanostructured bulk Bi0.5Sb1.5Te3 sample is found to have ZT ~0.51 at 375 K, which shows great potential for further improving the thermoelectric performance by this solution synthesis method. Considering the progress in n-type Bi–Te–Se composites, our results advocate the promise of bismuth/antimony chalcogenide nanocomposites towards practical thermoelectric applications.NRF (Natl Research Foundation, S’pore)MOE (Min. of Education, S’pore)Accepted versio