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Synthetic bone graft has gained considerable attention because of an increase in the aged population. In the present study, a biphasic bone graft composed of hydroxyapatite (HAp) and calcium sulfate (CS) is prepared using a gel-foaming technique. The gel is prepared at a temperature as low as 35 °C; many pores are introduced into the gel through an agitation process. The foamed gel can be cut into any shape and size. After sintering, the porosity of the biphasic bone graft is approximately 70%. Depending on the HAp/CS ratio, the amount of macropores and micropores can be tailored. The macropores of approximately 130 μm diameter are interconnected with each other through openings of 40 μm size. The biphasic bone graft exhibits no cytotoxicity; preosteoblast cells can adhere and proliferate on the surface of the fabricated bone graft. However, migration of these cells into the bone graft is considerably limited in the in vitro study. When the biphasic bone graft is implanted into the distal femur of rats, with the combined effect of osteoblast and osteoclast cells, more than 90% of the bone graft is degraded after 3 months. New trabeculae bone and bone marrow are observed within the bone defect. The HAp/CS composite can thus be used as degradable bone grafts.

Gene therapy for bone tissue engineering has been widely developed. Recently, non-viral DNA-based gene therapy has been reported to be a safer and more efficient method of delivering DNA into target cells. We used a non-viral gene transfection reagent to delivery bone morphogenetic protein-2 (BMP-2) gene into bone marrow stromal cells (BMSCs). Primary BMSCs were isolated from rat femurs and transfected with BMP-2 plasmids. The transfection rate was analyzed using flow cytometry. The concentration of BMP-2 protein was quantified using an enzyme-linked immunosorbent assay. Levels of osteopontin and osteocalcin were measured to evaluate osteogenic differentiation. In vivo, we designed a critical-size calvarial defect rat model to study new bone regeneration, using Matrigel as a scaffold to carry BMP-2-transfected bone marrow stromal cells into the defect site. New bone formation was assessed by micro-computed tomography, X-ray, immunohistochemical staining and histomophometry. The transfection rate after 72 h was 31.5%. The BMP-2 protein level as well as osteopontin and osteocalcin expressions were higher in the experimental group (transfected with BMP-2) than the control group (transfected with green fluorescent protein, GFP). The in vivo study suggested that bone healing occurred 12 weeks after scaffold implantation. In addition, BMP-2-transfected bone marrow stromal cells provided better osteogenic differentiation than primary bone marrow stromal cells. Our findings suggest that non-viral gene therapy may be useful in bone tissue engineering. Significance The study has clinical implications for the wider use of BMP-2-transfected BMSCs for cell-based transplantation therapy in bone regeneration.

Antipsychotic medications play an important role in treating psychotic disorders such as delusions, chaotic thoughts, and hallucinations. However, the excessive usage of antipsychotic drugs can cause numerous undesired effects which results in strong demand for drug detection. In this report, iron vanadate nanoparticles (FeV NPs) were synthesized using a mild hydrothermal process for the electrooxidation of thioridazine hydrochloride (TDZ). In detail, FeV NPs with 50–100 nm size were obtained from the starting materials of Fe(NO3)3·9H2O/NH4VO3/(C6H9NO)n at 120 °C for 6 h. Systematic investigations such as XRD, FT–IR, Raman, FE-SEM, TEM, and XPS analyses were performed to establish the structural, morphological, and compositional profile of the prepared FeV NPs. The electrochemical impedance spectroscopy (EIS) analysis exhibited fast electron transfer and the electrochemical experiments showed an excellent catalytic activity of FeV NPs modified electrode towards the electrooxidation of TDZ. As a result, the proposed electrode revealed a broad linear concentration range of 0.02–122.1 µM and the detection limit of 0.008 µM with exceptional selectivity in the existence of organic and inorganic compounds. As a proof of concept, the electrode was tested for the recognition of TDZ in human blood serum, with a high recovery range between 93% and 102%. The electrochemical sensing results put forward that the FeV NPs and their related composites will be a favorable candidate for sensing a variety of analytes in the future.

Since the EU introduced the European Landscape Convention (ELC) in 2000, the landscape has received growing attention in spatial planning and environmental impact assessments. To promote implementation of the ELC, the Swedish National Heritage Board proposed its Landscape Vision 2020, which addresses the goal of a ‘holistic landscape policy’. This study examined challenges and benefits brought by such a holistic approach to handling landscape protection/management within four issues in planning practice, namely cross-sector cooperation, local participation, integrating culture and nature, and bridging past and future. The analysis focused on a controversial road project passing through a World Heritage Site in Sweden. The results showed that the four issues were closely interlinked. In the case study, a new wave of cross-sector cooperation at authority level was observed, but it was also found to dominate the entire planning process and eventually limit the achievement of the other three issues. In conclusion, this study identified institutional culture and political context as key explanatory factors for understanding how the ELC and a holistic landscape view can be implemented in national practice.

The experimental study of a 3 kW organic Rankine cycle (ORC) system using an open-drive scroll type expander and R245fa has been investigated. The expander is originally hermetic-type refrigerant scroll compressor with built-in volume ratio of 3.24. The effects of pressure drop, degree of superheating and condenser temperature on system overall performance are examined. Moreover, the detailed behavior of pump and expander are explored. The experimental results show that the pressure drop exhibits a relatively higher sensitivity on system performance. The condenser temperature exhibits a negative effect on electrical power, thermal efficiency and system generating efficiency. The maximum expander shaft power, electrical power, thermal efficiency and system generating efficiency are 2.64 kW, 1.89 kW, 5.92% and 3.93%, respectively. The highest thermal efficiency does not represent the highest expander shaft power.

In this study, SnS2 powders with various surface morphologies are prepared using a facile solvothermal route with three different solvents. The powders synthesized in ethylene glycol and deionized water exhibit aggregates composed of nanoplates, whereas those synthesized in ethanol show flower-like microspheres (diameter: 1–2 µm) composed of nanosheets (thickness: 60–70 nm). The hierarchical flower-like microstructures can alleviate the volume change during charge/discharge cycles due to their porous nature. In addition, SnS2 synthesized at a lower temperature (100 °C) has nanoplates with a lower thickness, improving electrochemical performance. At a constant current density of 300 mA g−1, the microflowers exhibit a reversible capacity of 460 mAh g−1 after 100 cycles, a retention of 84%. More importantly, at a higher current density of 5000 mA g−1, a reversible capacity of 285 mAh g−1 is obtained. This study demonstrates that SnS2 synthesized using suitable processing design strategies can be used as an efficient active material for lithium-ion batteries.

In this study, experiments are carried out to examine the 3 kW organic Rankine cycle (ORC), investigating the influence of the heat source temperature and the flowrate of heat source on the system performance and heat recovery. Firstly, the behaviors of the evaporator and expander are examined. The efficiency and heat recovery effectiveness further discussed. The results indicated that the inlet temperature of the heat source exhibits a higher sensitivity on system efficiency than the flowrate due to the contribution of the heat transfer rate and power output. The system efficiency increases from 5.2% to 5.6% when the inlet temperature increase. However, the higher heat transfer rate leads to reduction of heat recovery from 60% to 40%. It indicated that the system efficiency may rise while the decrease in the heat recovery effectiveness are encountered with the increase in evaporating temperature. To tackle this inconsistency, the present study proposes a new appraisal, total heat recovery efficiency, defined by the multiplication of system efficiency and effectiveness. The proposed appraisal is more appropriate from the perspective of the heat recovery. Based on the experimental data, the proposed index can assess the performance of ORC subject to inlet temperature of heat source.

At the Chang Gung Memorial Hospital, a wobbled beam together with a set of single scatterers produces a uniform proton field at the first and second gantries for proton radiotherapy. Conformal field shaping was accomplished by using only a multileaf collimator (MLC) or a combination of an MLC and a brass aperture (downstream of the MLC). The MLC-only technique typically delivered extra low dose tails in penumbra compared to the dose delivered using both the MLC and brass aperture/block. This study attempted to provide a physical explanation of this phenomenon by Monte Carlo simulation and phase space analysis. The Particle Therapy System Simulation Framework was used as the Monte Carlo tool for beam propagation simulation. This research team investigated four possible causes for low dose tails including, (a) same-side MLC scattering; (b) opposite-side MLC scattering; (c) MLC transmission; and (d) proton angular distribution broadened by the wobbling magnets. The results indicated that the proton angular distribution broadened by the wobbling magnets is the single cause of low dose tails and can be stopped by inserting a downstream brass aperture.

Photopolymerized hydrogels are extensively investigated for various tissue engineering applications, primarily due to their ability to form hydrogels in a minimally invasive manner. Although photocrosslinkable hydrogels provide necessary biological and chemical characteristics to mimic cellular microenvironments, they often lack sufficient mechanical properties. Recently, nanocomposite approaches have demonstrated potential to overcome these deficits by reinforcing the hydrogel network with. In this study, we investigate some physical, chemical, and biological properties of photocrosslinked poly(ethylene glycol) (PEG)-silica hydrogels. The addition of silica nanospheres significantly suppresses the hydration degree of the PEG hydrogels, indicating surface interactions between the silica nanospheres and the polymer chains. No significant change in hydrogel microstructure or average pore size due to the addition of silica nanospheres was observed. However, addition of silica nanospheres significantly increases both the mechanical strength and the toughness of the hydrogel networks. The biological properties of these nanocomposite hydrogels were evaluated by seeding fibroblast cells on the hydrogel surface. While the PEG hydrogels showed minimum cell adhesion, spreading and proliferation, the addition of silica nanospheres enhanced initial cell adhesion, promoted cell spreading and increased the metabolic activity of the cells. Overall, results indicate that the addition of silica nanospheres improves the mechanical stiffness and cell adhesion properties of PEG hydrogels and can be used for biomedical applications that required controlled cell adhesion.

The structures and mechanical properties of both physically and covalently cross-linked nanocomposite hydrogels made from poly(ethylene glycol) (PEG) and silicate nanoparticles (Laponite RD) are investigated. Injectable nanocomposite precursor solutions can be covalently cross-linked via photopolymerization. The resulting hydrogels are transparent and have interconnected pores, high elongation and toughness. These properties depend on the hydrogel composition, polymer-nanoparticle interactions and degree of cross-linking (both physical and covalent). Covalent cross-linking of polymer chains leads to the formation of an elastic network, whereas physical cross-linking between nanoparticles and polymer chains induces viscoelastic properties. At high deformations covalent bonds may be broken but physical bonds rebuild and to some extent self-heal the overall network structure. Addition of silicate also enhances the bioactivity and adhesiveness of the hydrogel as these materials stick to soft tissue as well as to hard surfaces. In addition, MC3T3-E1 mouse preosteoblast cells readily adhere and spread on nanocomposite hydrogel surfaces. Collectively, the combinations of properties such as elasticity, stiffness, interconnected network, adhesiveness to surfaces and bio-adhesion to cells provide inspiration and opportunities to engineer mechanically strong and elastic tissue matrixes for orthopedic, craniofacial and dental applications.

Phorbol 12-myristate 13-acetate (PMA) is known to activate protein kinase C (PKC) and increase angiogenesis in cultured endothelial cells. Using a microRNA (miRNA) array, we found that PMA induced miR-146a expression in human microvascular endothelial cells. The miR-146a expression was dependent on dose and time and independent of PKC activation. Using a combined approach involving predictions using miRanda algorithm and whole genome microarray experiments with or without inhibition of miR-146a expression by LNA-antimir-146a or LNA-control, 29 potential target genes of miR-146a were identified. Because endothelial cell S phase progression is an early event in the induction of angiogenesis, we evaluated 5 cell cycle-related genes from the 29 target genes and found that the transcripts of 3 genes (CCNA2, PA2G4, and BRCA1) were downregulated after PMA treatment, but their expression was rescued upon miR-146a inhibition. However, inhibition of miR-146a expression failed to alter the cell cycle distribution or angiogenesis induced by PMA treatment. By using a combined approach involving computational prediction and a whole genome microarray experiment in the presence or absence of antimir, the observations in this presented article raise the possibility that antimir strategies might be used to identify the potential miRNA targets.

To understand the molecular mechanisms that direct the expression of the gene encoding the platelet-activating factor (PAF) receptor, the 5′-flanking region of the human PAF receptor gene was cloned, and its promoter activity in myeloid cell lines was characterized. By the 5′-rapid amplification of cDNA ends method and primer extension, the transcription initiation site was mapped to an adenosine residue 137 bases upstream of the ATG translation initiation codon. The promoter region lacks a typical TATA or CCAAT box. However, the sequence encompassing the transcription initiation site shows high homology to the initiator (Inr) sequence. Transfection of promonocytic U937 cells with recombinant plasmids containing a series of truncated segments of the 5′-flanking region linked to the luciferase reporter gene revealed that the sequence from nucleotides −44 to +27 relative to the transcription initiation site was sufficient to promote a high level of gene expression. The promoter activity was much lower in nonexpressing HeLa cells and promyelocytic HL-60 cells, which express relatively low levels of the PAF receptor. Gel mobility shift analysis demonstrated the binding of nuclear factors extracted from myelocytic cells to the −16/+18 sequence containing the Inr element. No binding activity was detected using the nuclear extracts from the nonmyelocytic HeLa cells. The DNA-protein complexes were sequence-specific since the binding was not significantly affected by the mutated Inr sequences or the Inr sequence of the terminal deoxynucleotidyltransferase gene. Furthermore, point mutations in the Inr element significantly reduced promoter activity in both U937 and THP-1 cell lines. When Me2SO or retinoic acid was used to induce granulocytic differentiation of HL-60 cells, a distinct Inr-protein complex was induced concurrently, but the complex was not observed in 12-O-tetradecanoylphorbol-13-acetate-induced monocytic differentiated HL-60 cells or Me2SO-induced differentiated U937 cells, indicating that the inducible Inr binding activity is granulocyte-specific. These results suggest that distinct nuclear factors interact with the unique Inr element and play a role in the transcriptional regulation of the PAF receptor in various myeloid cells.