Osteogenic Properties of Novel Methylsulfonylmethane-Coated Hydroxyapatite Scaffold

Despite numerous advantages of using porous hydroxyapatite (HAp) scaffolds in bone regeneration, the material is limited in terms of osteoinduction. In this study, the porous scaffold made from nanosized HAp was coated with different concentrations of osteoinductive aqueous methylsulfonylmethane (MSM) solution (2.5, 5, 10, and 20%) and the corresponding MH scaffolds were referred to as MH2.5, MH5, MH10, and MH20, respectively. The results showed that all MH scaffolds resulted in burst release of MSM for up to 7 d. Cellular experiments were conducted using MC3T3-E1 preosteoblast cells, which showed no significant difference between the MH2.5 scaffold and the control with respect to the rate of cell proliferation (p > 0.05). There was no significant difference between each group at day 4 for alkaline phosphatase (ALP) activity, though the MH2.5 group showed higher level of activity than other groups at day 10. Calcium deposition, using alizarin red staining, showed that cell mineralization was significantly higher in the MH2.5 scaffold than that in the HAp scaffold (p < 0.0001). This study indicated that the MH2.5 scaffold has potential for both osteoinduction and osteoconduction in bone regeneration.     

Numerical investigation on the hovering performance of contra-rotating ducted rotor for micro air vehicle

Microsystem Technologies - In this study, the hovering performance of contra rotating ducted rotor (CRDR) for micro air vehicle (MAV) was performed by using computational fluid dynamics technique....     

Encapsulation of Pt nanocatalyst with N-containing carbon layer for improving catalytic activity and stability in the hydrogen evolution reaction

As hydrogen emerges as a next-generation clean energy source, the production of hydrogen is generating much research interest. Water electrolysis, one of the promising methods of hydrogen production, has the advantage of no resource depletion or carbon dioxide emissions. In this study, a Pt@C core–shell catalyst in which an N-containing carbon layer covers individual Pt nanoparticles was applied to the hydrogen evolution reaction (the cathodic reaction of water electrolysis), and the effect of the carbon shell on the activity and stability of the catalyst was investigated. The catalyst was synthesized by simple annealing of Pt-aniline complexes at 600 °C in a N₂ atmosphere. The thermal decomposition of aniline during annealing resulted in N-containing carbon shells. The carbon shell had a positive effect on both the activity and stability of the catalyst in the hydrogen evolution reaction. Graphitic N and pyridinic N on the carbon shell, along with Pt, served as active sites for the hydrogen evolution reaction, increasing the catalytic activity. The carbon shell also effectively protected the Pt core from dissolution and agglomeration while allowing the transport of the reactant protons through the shell, improving stability with minimal loss of catalytic activity.     

Multiscale modeling and control of Kappa number and porosity in a batch-type pulp digester

This work proposes a multiscale modeling and model-based feedback control framework for the delignification process in a batch-type pulp digester. Specifically, we focus on a hardwood chip in the digester and develop a multiscale model capturing both the evolution of microscopic properties such as the pore size and shape distributions in the solid phase and the dynamic changes in the temperature and component concentrations in the liquor phase. While the macroscopic model adopts the continuum hypothesis based on the Purdue model, a novel microscopic model is developed using a kinetic Monte Carlo algorithm, accounting for the dissolution of lignin, cellulose, and hemicellulose contacting the liquor phase. A reduced-order model was built to design a Luenberger observer for state estimation, which is then used to develop a model-based control system. The simulation results demonstrated that the proposed methodology was able to regulate both the Kappa number and porosity to desired values.     

Application of offset-free Koopman-based model predictive control to a batch pulp digester

This work presents the application of a Koopman operator approach to a batch pulp digester. To manufacture paper products with desired properties, it is essential to consider both macroscopic and microscopic attributes of pulp. However, the complexity of multiscale dynamics of pulping processes hinders proper control system design. Therefore, we utilize extended dynamic mode decomposition (EDMD), which is based on Koopman operator theory, to derive a global linear representation of a pulp digester. Then, we design an offset-free Koopman-based model predictive control (KMPC) system to regulate the Kappa number and cell wall thickness (CWT) of fibers at a batch pulp digester while compensating for the influence of plant-model mismatch and disturbance during operation. The numerical experiments demonstrate that the linear state-space model, obtained via EDMD, properly predicts the behavior of a batch pulp digester, and the designed offset-free KMPC system successfully drives the Kappa number and CWT to set-point values.     

Rapid Screening of Glucocorticoid Receptor (GR) Effectors Using Cortisol-Detecting Sensor Cells

Cortisol, a stress hormone, plays key roles in mediating stress and anti-inflammatory responses. As abnormal cortisol levels can induce various adverse effects, screening cortisol and cortisol analogues is important for monitoring stress levels and for identifying drug candidates. A novel cell-based sensing system was adopted for rapid screening of cortisol and its functional analogues under complex cellular regulation. We used glucocorticoid receptor (GR) fused to a split intein which reconstituted with the counterpart to trigger conditional protein splicing (CPS) in the presence of targets. CPS generates functional signal peptides which promptly translocate the fluorescent cargo. The sensor cells exhibited exceptional performance in discriminating between the functional and structural analogues of cortisol with improved sensitivity. Essential oil extracts with stress relief activity were screened using the sensor cells to identify GR effectors. The sensor cells responded to peppermint oil, and L-limonene and L-menthol were identified as potential GR effectors from the major components of peppermint oil. Further analysis indicated L-limonene as a selective GR agonist (SEGRA) which is a potential anti-inflammatory agent as it attenuates proinflammatory responses without causing notable adverse effects of GR agonists.     

Ligand-Induced GPR110 Activation Facilitates Axon Growth after Injury

Recovery from axonal injury is extremely difficult, especially for adult neurons. Here, we demonstrate that the activation of G-protein coupled receptor 110 (GPR110, ADGRF1) is a mechanism to stimulate axon growth after injury. N-docosahexaenoylethanolamine (synaptamide), an endogenous ligand of GPR110 that promotes neurite outgrowth and synaptogenesis in developing neurons, and a synthetic GPR110 ligand stimulated neurite growth in axotomized cortical neurons and in retinal explant cultures. Intravitreal injection of GPR110 ligands following optic nerve crush injury promoted axon extension in adult wild-type, but not in gpr110 knockout, mice. In vitro axotomy or in vivo optic nerve injury rapidly induced the neuronal expression of gpr110. Activating the developmental mechanism of neurite outgrowth by specifically targeting GPR110 that is upregulated upon injury may provide a novel strategy for stimulating axon growth after nerve injury in adults.     

Effects of 1,2-dioleoyl-sn-glycero-3-phosphocholine on moisture content and oxidative stability in soybean oil–water system at different interfaces

Food Science and Biotechnology - Effects of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) on the oxidative stability were determined in soybean oil–water system at different locations...     

Comparative Proteomic Analysis of the Mesenchymal Stem Cells Secretome from Adipose,Bone Marrow,Placenta and Wharton’s Jelly

Mesenchymal stem cells (MSCs) have the potential to be a viable therapy against various diseases due to their paracrine effects, such as secretion of immunomodulatory, trophic and protective factors. These cells are known to be distributed within various organs and tissues. Although they possess the same characteristics, MSCs from different sources are believed to have different secretion potentials and patterns, which may influence their therapeutic effects in disease environments. We characterized the protein secretome of adipose (AD), bone marrow (BM), placenta (PL), and Wharton’s jelly (WJ)-derived human MSCs by using conditioned media and analyzing the secretome by mass spectrometry and follow-up bioinformatics. Each MSC secretome profile had distinct characteristics depending on the source. However, the functional analyses of the secretome from different sources showed that they share similar characteristics, such as cell migration and negative regulation of programmed cell death, even though differences in the composition of the secretome exist. This study shows that the secretome of fetal-derived MSCs, such as PL and WJ, had a more diverse composition than that of AD and BM-derived MSCs, and it was assumed that their therapeutic potential was greater because of these properties.     

Estimates of particulate matter inhalation doses during three-dimensional printing

Harmful emissions including particulates, volatile organic compounds, and aldehydes are generated during three-dimensional (3D) printing. Ultrafine particles are particularly important due to their ability to penetrate deep into the lung. We modeled inhalation exposure by particle size during 3D printing. A total of six thermoplastic filaments were used for printing under manufacturer's recommended conditions, and particle emissions in the size range between 10 nm and 10 μm were measured. The inhalation exposure dose including inhaled and deposited doses was estimated using a mathematical model. For all materials, the number of particles between 10 nm and 1 μm accounted for a large proportion among the released particles, with nano-sized particles being the dominant size. More than 1.3 × 10⁹ nano-sized particles/kgbw/g (95.3 ± 104.0 ng/kgbw/g) could be inhaled, and a considerable amount was deposited in respiratory regions. The total deposited dose in terms of particle number was 3.1 × 10⁸ particles/kgbw/g (63.6% of the total inhaled dose), and most (41.3%) were deposited in the alveolar region. The total mass of particles deposited was 19.8 ± 16.6 ng/kgbw/g, with 10.1% of the total mass deposited in the alveolar region. Given our findings, the inhalation exposure level is mainly determined by printing conditions, particularly the filament type and manufacturer-recommended extruder temperature.