[Design of new gradient scaffolds based on triply periodic minimal surfaces and study on its mechanical, permeability and tissue differentiation characteristics].

In order to establish a bone scaffold with good biological properties, two kinds of new gradient triply periodic minimal surfaces (TPMS) scaffolds, i.e., two-way linear gradient G scaffolds (L-G) and D, G fusion scaffold (N-G) were designed based on the gyroid (G) and diamond (D)-type TPMS in this study. The structural mechanical parameters of the two kinds of scaffolds were obtained through the compressive simulation. The flow property parameters were also obtained through the computational fluid dynamics (CFD) simulation in this study, and the permeability of the two kinds of scaffolds were calculated by Darcy's law. The tissue differentiation areas of the two kinds of scaffolds were calculated based on the tissue differentiation theory. The results show that L-G scaffold has a better mechanical property than the N-G scaffold. However, N-G scaffold is better than the L-G scaffold in biological properties such as permeability and cartilage differentiation areas. The modeling processes of L-G and N-G scaffolds provide a new insight for the design of bone scaffold. The simulation in this study can also give reference for the prediction of osseointegration after the implantation of scaffold in the human body.

Effect of Heat Treatment on the Chemical Structure and Thermal Properties of Softwood-Derived Glycol Lignin.

A large-scale glycol lignin (GL) production process (50 kg wood meal per batch) based on acid-catalyzed polyethylene glycol (PEG) solvolysis of Japanese cedar (JC) was developed at the Forestry and Forest Products Research Institute (FFPRI), Tsukuba, Japan. JC wood meal with various particle size distributions (JC-S < JC-M < JC-L) (average meal size, JC-S (0.4 mm) < JC-M (0.8 mm) < JC-L (1.6 mm)) and liquid PEG with various molecular masses are used as starting materials to produce PEG-modified lignin derivatives, namely, GLs, with various physicochemical and thermal properties. Because GLs are considered a potential feedstock for industrial applications, the effect of heat treatment on GL properties is an important issue for GL-based material production. In this study, GLs obtained from PEG400 solvolysis of JC-S, JC-M, and JC-L were subjected to heating in a constant-temperature drying oven at temperatures ranging from 100 to 220 °C for 1 h. All heat-treated GL series were thermally stable, as determined from the Klason lignin content, TMA, and TGA analyses. SEC analysis suggests the possibility of condensation among lignin fragments during heat treatment. ATR-FTIR spectroscopy, thioacidolysis, and 2D HSQC NMR demonstrated that a structural rearrangement occurs in the heat-treated GL400 samples, in which the content of α-PEG-ß-O-4 linkages decreases along with the proportional enrichments of ß-5 and ß-ß linkages, particularly at treatment temperatures above 160 °C.

The effects of adding ground terebinth fruits on the emulsification, microstructural, and flow properties of meat emulsions.

The effect of roasted and unroasted terebinth on the colour, emulsion capacity, flow properties, emulsion stability, microstructure, and textural properties of the meat emulsions was researched. The meat emulsions were created by adding the roasted and unroasted terebinth at four concentrations (0.0, 0.1, 0.3, and 0.5%) to the beef. The emulsion capacity and stability increased with the addition of terebinth, and the highest values for the emulsion capacity (233.50 ml oil/g protein) and stability (74.50%) were observed at the terebinth concentration of 0.3%. The emulsion stability and capacity of samples containing roasted terebinth were higher than those of samples containing unroasted terebinth. The viscosities of the samples with roasted terebinth increased with increasing concentration. The pseudo-plasticity increased with the addition of terebinth. As a result, the use of terebinth in high-fat emulsion-type products might be a potential herbal additive to improve its technological and functional properties.

Modification of Bulk Density, Flow Property and Crystallinity of Microcrystalline Cellulose Prepared from Waste Cotton.

The most affordable type of tablet is the immediately compressible tablet, which uses microcrystalline cellulose (MCC), a popular pharmaceutical excipient, as a filler or binder. To make it compatible with different active drugs and excipients, we tried to change some physical properties of the MCC. In the current study, we used a chelating agent to pretreat the waste cotton before pulping, bleaching, and finally, hydrochloric acid degradation with a concentration of 2N at 100 °C temperature for 20 min to prepare MCC. The prepared MCC was treated with different concentrations of sodium hydroxide at room temperature or at -20 °C followed by precipitation with hydrochloric acid or ethanol with complete washing with distilled water till neutralization. Evaluation of the degree of polymerization (DP) and FT-IR spectrum confirm the identity of the microcrystalline cellulose. The DP was found to be 216. The bulk density of the unmodified MCC was 0.21 while that of modified MCC varied from 0.253 to 0.594. The modified MCC powder showed good flow properties compared to the unmodified MCC as evaluated by the Hausner index, Carr's index and the angle of repose. The scanning electron microscopy (SEM) of the MCC revealed that the rod shape has been changed to an oval shape due to treatment with sodium hydroxide at -20 °C. The X-ray crystallographic (XRD) analysis indicated that the unmodified MCC and standard MCC showed the crystallinity index (CrI) value of 86.82% and 87.63%, respectively, while the value ranges from 80.18% to 60.7% among the modified MCC powder. The differences in properties of the MCC might be due to the variation of rearrangement of the cellulose chain among the MCC particles due to treatment with different concentrations of a base at different temperatures and precipitation environments. This has enabled us to prepare MCC with different properties which might be compatible with different drugs.

Influence of milling methods on the flow properties of ivory teff flour.

Increasing teff (Eragrostis tef) consumption has been recorded in recent years due to its gluten-free nature and exceptional nutritional composition. Studies on the particle level that relates to processing and handling of teff flour are limited. The effect of different milling methods (roller mill, pin mill, and hammer mill) on size distribution, shape characteristics, and flowability of teff flour was evaluated. Physical properties (angle of repose, tapped and bulk densities, size distribution, and shape characteristics) and proximate composition were investigated and correlated with flow properties. Flowability was measured in terms of bulk, shear, and dynamic flow properties using the FT4 powder rheometer. Particle size distribution significantly (p < .05) influenced the angle of repose, aeration energy, and wall friction angle while shape characteristics (circularity and aspect ratio) significantly (p < .05) affected the aerated and tapped bulk densities and basic flow energy. Hammer-milled flour had the highest aerated (548.00 kg/m3 ) and tapped bulk densities (804.33 kg/m3 ). Pin-milled flour had the highest compressibility index (38.46%), Hausner ratio (1.62), angle of repose (71.57°), and wall friction angle (25.92° at 3 kPa) indicating poorer flowability. Stability index and specific energy did not vary significantly (p > .05) among the milled flours. Highest basic flow (1,191.03 mJ) and aerated energies (272.32 mJ) were required to induce flow in hammer-milled flour due to greater proportion of large particles. Based on the flow function, all flours fall under the "easy flowing" category, but the pin-milled flour exhibited the poorest flowability.

Polymer Cold-Flow Improvers for Biodiesel.

In recent decades, biodiesel has been explored as a prospective comparable fuel to petroleum diesel for compression ignition engines. However, several drawbacks have limited the wide application of biodiesel as motor fuel, and the poor cold-flow property is one of the major problems. This problem is compounded by the diversity of the biodiesel characteristics arising from a variety of chemical compositions of biodiesel from different sources. Among the methods investigated to improve the cold-flow properties of biodiesel, the use of additives seems highly promising. Despite the significant number of publications, the potential of this method is still far from having been completely discovered or exploited. In the present review, we briefly describe the sources, chemical composition, and physico-chemical characteristics of the main types of biodiesel. Next, we discuss the examples of the use of different polymer additives for the improvement of the cold-flow characteristics of biodiesel and biodiesel/petroleum diesel blends. Additionally, we tried to assess the prospects of the polymer additives to enhance biodiesel performance. The main conclusion of this survey is that innovative and high-efficiency cold-flow improvers for biodiesel should be further developed.

A Comprehensive Review on Pellets as a Dosage Form in Pharmaceuticals.

Oral route of administration is widely accepted and desired because of its versatility, convenience, and, most importantly, patient compliance. Multiparticulate systems like granules and pellets are more advantageous when compared to single-unit dosage forms, as they are capable of distributing the drug more evenly in the gastrointestinal tract. The current paper focuses on pellets, the merits and demerits associated, various pelletization techniques, and their characterization. It also focuses on how pellets can be employed for drug delivery is controlled and sustained release formulations. It gives a complete emphasis on the drug and excipients that can be used in pellet formation, the marketed formulations, and the research pertaining to pellets.

Effects of Processing on a Sustained Release Formulation Prepared by Twin-Screw Dry Granulation.

Dry granulation is an indispensable process used to improve the flow property of moisture-sensitive materials. Considering the limitations of currently available dry granulation techniques, it is necessary to develop a novel technique. In this study, a twin-screw dry granulation (TSDG) technology was successfully applied to produce a sustained-release dry granule formulation, which was subsequently compressed into sustained-release tablets. Based on a preliminary study, theophylline was selected as model drug, Klucel™ EF, Ethocel™, and magnesium stearate were selected as excipients. A Resolution V Irregular Fraction Design was applied to determine the effect of different processing parameters (screw speed, feeding rate, barrel temperature, and screw configuration) on product properties (flow properties, particle size distribution, and dissolution time). A reliable model was achieved by combining the data obtained, and processing parameters were automatically optimized to attain the setting goal. In general, TSDG was demonstrated to be an alternative method for the preparation of dry granules. The continuous processing nature, simplicity of operation, and ease of optimization made TSDG competitive compared with other conventional dry granulation techniques.

Influence of polymethyl acrylate additive on the formation of particulate matter and NOX emission of a biodiesel-diesel-fueled engine.

The aim of this study is to investigate the effect of the polymethyl acrylate (PMA) additive on the formation of particulate matter (PM) and nitrogen oxide (NOX) emission from a diesel coconut and/or Calophyllum inophyllum biodiesel-fueled engine. The physicochemical properties of 20% of coconut and/or C. inophyllum biodiesel-diesel blend (B20), 0.03 wt% of PMA with B20 (B20P), and diesel fuel were measured and compared to ASTM D6751, D7467, and EN 14214 standard. The test results showed that the addition of PMA additive with B20 significantly improves the cold-flow properties such as pour point (PP), cloud point (CP), and cold filter plugging point (CFPP). The addition of PMA additives reduced the engine's brake-specific energy consumption of all tested fuels. Engine emission results showed that the additive-added fuel reduce PM concentration than B20 and diesel, whereas the PM size and NOX emission both increased than B20 fuel and baseline diesel fuel. Also, the effect of adding PMA into B20 reduced Carbon (C), Aluminum (Al), Potassium (K), and volatile materials in the soot, whereas it increased Oxygen (O), Fluorine (F), Zinc (Zn), Barium (Ba), Chlorine (Cl), Sodium (Na), and fixed carbon. The scanning electron microscope (SEM) results for B20P showed the lower agglomeration than B20 and diesel fuel. Therefore, B20P fuel can be used as an alternative to diesel fuel in diesel engines to lower the harmful emissions without compromising the fuel quality.

An investigation of effects of modification processes on physical properties and mechanism of drug release for sustaining drug release from modified rice.

The aim of this study was to investigate the effect of modification processes on physical properties and explain the mechanism of sustained drug release from modified rice (MR). Various types of Vietnamese rice were introduced in the study as the matrices of sustained release dosage form. Rice was thermally modified in water for a determined temperature at different times with a simple process. Then tablets containing MR and isradipine, the model drug, were prepared to investigate the capability of sustained drug release. Scanning electron microscopy (SEM) was used to determine different morphologies between MR formulations. Flow property of MR was analyzed by Hausner ratio and Carr's indices. The dissolution rate and swelling/erosion behaviors of tablets were evaluated at pH 1.2 and pH6.8 at 37±0.5°C. The matrix tablet containing MR showed a sustained release as compared to the control. The SEM analyses and swelling/erosion studies indicated that the morphology as well as swelling/erosion rate of MR were modulated by modification time, drying method and incubation. It was found that the modification process was crucial because it could highly affect the granule morphologies and hence, leading to the change of flowability and swelling/erosion capacity for sustained release of drug.

Effect of Salivary Reaction Time on Flow Properties of Commercial Food Thickeners Used for Dysphagic Patients.

The effect of human saliva on the flow properties of pudding-like thickened water prepared with commercial food thickeners was investigated, and their viscosity differences were also compared as a function of salivary reaction time (0-60 min after the addition of saliva). Food thickeners used in this study were starch-based (SB), gum-containing starch-based (GSB), and gumbased (GB) commercial thickeners marketed in Korea. GB showed no significant reduction in viscosity upon contact with human saliva during the salivary reaction. In contrast, SB almost completely lost its viscosity shortly after the addition of saliva, and GSB significantly reduced its viscosity after 20 min of reaction time but retained its viscosity. The results of this study indicate that GB can enhance the swallowing safety of dysphagic patients by retaining a stable viscosity level without the reduction of viscosity during consumption of thickened fluids, whereas SB may increase the possibility of aspiration owing to a rapid decrease of viscosity upon contact with human saliva.

Functionality of maize, wheat, teff and cassava starches with stearic acid and xanthan gum.

Consumer concerns to synthetic chemicals have led to strong preference for 'clean' label starches. Lipid and hydrocolloids are food friendly chemicals. This study determines the effects of stearic acid and xanthan gum alone and in combination on the functionality of maize, wheat, teff and cassava starches. An increase in viscosity was observed for all starches with stearic acid and xanthan gum compared to the controls with cassava having the least increase. A further increase in viscosity was observed for the cereal starches with combination of stearic acid and xanthan gum. Stearic acid reduced retrogradation, resulting in soft textured pastes. Combination of stearic acid and xanthan gum reduced the formation of type IIb amylose-lipid complexes, syneresis, and hysteresis in cereal starches compared to stearic acid alone. A combination of stearic acid and xanthan gum produce higher viscosity non-gelling starches and xanthan gum addition increases physical stability to freezing and better structural recovery after shear.

Design of new gradient scaffolds based on triply periodic minimal surfaces and study on its mechanical, permeability and tissue differentiation characteristics / 生物医学工程学杂志

In order to establish a bone scaffold with good biological properties, two kinds of new gradient triply periodic minimal surfaces (TPMS) scaffolds, i.e., two-way linear gradient G scaffolds (L-G) and D, G fusion scaffold (N-G) were designed based on the gyroid (G) and diamond (D)-type TPMS in this study. The structural mechanical parameters of the two kinds of scaffolds were obtained through the compressive simulation. The flow property parameters were also obtained through the computational fluid dynamics (CFD) simulation in this study, and the permeability of the two kinds of scaffolds were calculated by Darcy's law. The tissue differentiation areas of the two kinds of scaffolds were calculated based on the tissue differentiation theory. The results show that L-G scaffold has a better mechanical property than the N-G scaffold. However, N-G scaffold is better than the L-G scaffold in biological properties such as permeability and cartilage differentiation areas. The modeling processes of L-G and N-G scaffolds provide a new insight for the design of bone scaffold. The simulation in this study can also give reference for the prediction of osseointegration after the implantation of scaffold in the human body.

Effect of Salivary Reaction Time on Flow Properties of Commercial Food Thickeners Used for Dysphagic Patients

The effect of human saliva on the flow properties of pudding-like thickened water prepared with commercial food thickeners was investigated, and their viscosity differences were also compared as a function of salivary reaction time (0-60 min after the addition of saliva). Food thickeners used in this study were starch-based (SB), gum-containing starch-based (GSB), and gumbased (GB) commercial thickeners marketed in Korea. GB showed no significant reduction in viscosity upon contact with human saliva during the salivary reaction. In contrast, SB almost completely lost its viscosity shortly after the addition of saliva, and GSB significantly reduced its viscosity after 20 min of reaction time but retained its viscosity. The results of this study indicate that GB can enhance the swallowing safety of dysphagic patients by retaining a stable viscosity level without the reduction of viscosity during consumption of thickened fluids, whereas SB may increase the possibility of aspiration owing to a rapid decrease of viscosity upon contact with human saliva.