Addition Of SF Research Articles

Experimental evaluation and statistical modeling of sustainable sisal fiber-reinforced fly ash-based lateritic concrete using response surface methodology

This research uses waste laterite scraps as coarse aggregates in sisal fiber-reinforced fly ash-based lateritic concrete and evaluates its strength properties to create sustainable concrete. By lowering the requirement for virgin materials, its use lessens the need for granite mining, environmental contamination, and the preservation of natural resources. Using response surface methodology (RSM’s) central composite design (CCD), twenty-nine different lateritic concrete mixtures have been designed with varying input factor combinations (LA: 25%–100%, FA: 5%–20%, SF: 0.25%–1%, and SP: 1%–1.6%) with a total of 279 test specimens were cast and tested for responses like compressive, split-tensile, and flexural strengths at 28 days. The analysis of variance (ANOVA) test was performed to determine the accuracy of the mathematical models developed following the experimental results. Quadratic models were proposed due to a higher coefficient of determination (R2) for all responses. The higher addition of laterite aggregate linearly reduces fresh concrete’s workability. The compressive strength of the M30 grade concretes for 28 days increased by 11.20% when 25% of the granite aggregates were substituted with laterite aggregates. Compressive strength decreases above 25% replacement. Similarly, split tensile and flexural strengths are increased over the control mix by 10.86% and 5.88%, respectively. Multi-objective optimization was used to study the interactions between the different components and determine the appropriate mixing ratio. Considering the goals of multi-objective optimization, the optimal mix of sisal fiber-reinforced fly ash-based lateritic concrete may be produced with LA substitution of 25%, FA substitution of 10.52%, SF addition of 1%, and SP addition of 1.48%. Experimental validation was carried out with an error rate of less than 5% of the anticipated optimal data.

Co-utilization of sepiolite and ferromanganese ore reduces rice Cd and As concentrations via soil immobilization and root Fe-Mn plaque resistance

Cadmium (Cd) and arsenic (As), common toxic elements in farmland soil, are easily absorbed by rice and accumulate in grains. Combined amendment is likely to ameliorate Cd-As-contaminated soil; however, studies on this aspect are limited. Therefore, we explored the effects of co-utilizing sepiolite and ferromanganese ore (SF) on Cd-As accumulation in rice by conducting pot experiments on Cd-As-contaminated paddy soil. The results showed that 4 g kg−1 SF (4SF) reduced Cd (55.9 %/48.5 %) and As (82.9 %/64.7 %) concentrations in grain in early and late rice. The Fe concentration in Fe-Mn plaque (IMP) (FeIMP) first decreased and then increased, and the Mn concentration in IMP (MnIMP) increased with an increase in the SF addition amount. This resulted in the 4SF treatment maximizing the Cd adsorption capacity of IMP, whereas the 2 g kg−1 SF treatment (2SF) minimized the As adsorption capacity of IMP. More importantly, when the total Cd and As were 9.7 mg kg−1 and 304.2 mg kg−1, respectively, in the soil, 4SF application reduced CaCl2-extractable Cd (80.5 %/87.9 %), and 2SF reduced available As (24.0 %/20.9 %) in early and late rice. Additionally, SF decreased the Cd and As ion contents in soil pore water. Overall, SF has good immobilization and sustained effect on Cd-As and can be used as an effective material for remediation of Cd-As-contaminated soil.

Stimulating the efficiency of Cd-phytoremediation from contaminated soils by Solanum nigrum L.: Effect of foliar and soil application of yeast extract

Black nightshade (Solanum nigrum L.) is an annual grass and is known as a Cd-hyperaccumulator. The current study aims to use a natural biostimulant, i.e., yeast extract, to improve the phytoremediation capacity of S. nigrum in a pot experiment. S. nigrum was cultivated in a Cd-contaminated soil and treated with yeast extract (20% w/v) via soil or foliar application. The experiment included four treatments: control (C), yeast extract applied via soil (S), yeast extract applied via foliar spraying (F), and yeast extract applied via soil and foliar application (SF). The treatments of yeast extract were laid out in a completely randomized design (CRD) with six replicates. The plants of S. nigrum sprayed with yeast extract in combination with soil addition had the highest significant values of Cd in the plant shoot. The addition of yeast extract significantly increased the phytoremediation indexes compared to the control. The addition of yeast extract to the soil or via foliar spraying significantly enhanced the translocation factor (TF) and bioaccumulation factor (BAF) of Cd in S. nigrum plants. The combined addition of soil and foliar spraying of yeast extract (SF) was more effective than the sole addition of S or F in increasing the TF and BAF of Cd by S. nigrum. The addition of SF increased both the TF and BAF by 50% above the control. The yeast extract significantly enhanced the activity of superoxide dismutase (SOD) and peroxidase (POD). The combined addition of SF was more effective in enhancing the concentrations of proline and soluble carbohydrates in the plant leaves than the sole addition of each treatment. The maximum nutrient uptake and photosynthesis pigments, i. e., chlorophyll, were achieved from the addition of yeast extract to the soil in combination with foliar spraying. The yeast extract improved S. nigrum's Cd-phytoextraction capacity by protecting photosynthesis pigments and increasing antioxidant defenses and plant nutrient uptake. S. nigrum plants have many characteristics that qualify them for use in cleaning Cd-contaminated soils. However, it is recommended that yeast extract be sprinkled on the leaves and added directly to the soil to improve phytoremediation efficiency.

α-Tricalcium phosphate cement reinforced with silk fibroin: A high strength biomimetic bone cement with chloride-substituted hydroxyapatite

In the past decades, bone defects have become an increasing factor in the development of disability in patients, impacting their quality of life. Large bone defects have minor chances to self-repair, requiring surgical intervention. Therefore, α-TCP-based cements are rigorously studied for the development of bone filling and replacement applications due to the possibility of application in minimally invasive procedures. However, α-TCP-based cements do not present adequate mechanical properties for most orthopedic applications. The aim of this study is to develop a biomimetic α-TCP cement reinforced with 0.250–1.000 wt% of silk fibroin using non-dialyzed SF solutions. Samples with SF additions higher than 0.250 wt% presented complete transformation of the α-TCP to a biphasic CDHA/HAp-Cl material, which could enhance the osteoconductivity of the material. Samples reinforced with concentrations of 0.500 wt% SF showed an increase of 450% of the fracture toughness and 182% of the compressive strength of the control sample, even with 31.09% porosity, which demonstrates good coupling between the SF and the CPs. All samples reinforced with SF showed a microstructure with smaller needle-like crystals when compared to the control sample, which possibly contributed to the material's reinforcement. Moreover, the composition of reinforced samples did not affect the cytotoxicity of the CPCs and enhanced the cell viability presented by the CPC without SF addition. Hence, biomimetic CPCs with mechanical reinforcement through the addition of SF were successfully obtained through the developed methodology, with the potential to be further evaluated as a suitable material for bone regeneration.

Effect of binder strengthening using micro-silica on mechanical and absorption characteristics of HPC reinforced with reclaimed jute fibres

The incorporation of dispersed fibres in the binder matrix is proven to be beneficial to the tensile performance of high-performance concrete (HPC). However, the insertion of new/virgin fibres in the ‘concrete matrix’ significantly adds to the final cost and embodied carbon of HPC. Therefore, the environment-friendly design of fibre-reinforced HPC remains the main challenge. In this study, the influence of different volume fractions (Vol.) of ‘jute fibre’ (JF) was examined on the engineering performance of HPC. The effect of micro-silica/silica fume (SF) inclusion as a secondary binder was also analysed on the performance of JF-reinforced HPC. To investigate the mechanical performance of designed mixes, compression, flexure, and splitting-tensile tests were conducted at 28 and 91 days. Non-destructive durability performance indicators, such as ‘water-absorption (WA)’, ‘rapid chloride-ion permeability (RCIP)’, ‘electrical-resistivity (ER)’, and ‘ultrasonic-pulse velocity (UPV)’ were also examined. It was found that the utilisation ratio/efficiency of JF addition improved with the ageing of samples. Moreover, the inclusion of SF proved to be beneficial in the strength gain due to JF addition. The combined use of 0.3% vol. of JF and SF improved the ‘compressive strength (CS)’ by 26–30%. The inclusion of 0.3% vol. of JF improved the ‘splitting-tensile strength (STS)’ of plain HPC by 43% and 23% with and without the SF inclusion, respectively. The JF incorporation showed a minor decrease in the imperviousness of HPC. SF incorporation helped minimise the damaging effect of JF incorporation on the ER, WA resistance, and UPV value of HPC. Owing to the addition of SF, the WA capacity of JF-reinforced mixes was decreased by up to 30% at 28 days and up to 50% at 91 days. While the RCIP values of JF-reinforced mixes were dropped by 40–60% (depending on the JF content) owing to the superior pozzolanic and filler effect of SF.

In Situ Electrospinning of "Dry-Wet" Conversion Nanofiber Dressings for Wound Healing.

Rapid wound dressings provide an excellent solution strategy for the treatment of wounds in emergency situations. In this study, aqueous solvent-based PVA/SF/SA/GelMA nanofiber dressings fabricated by a handheld electrospinning device could deposit quickly and directly on the wound, perfectly fitting wounds with various sizes. Using an aqueous solvent overcame the disadvantage of using the current organic solvents as the medium for rapid wound dressings. The porous dressings had excellent air permeability to ensure smooth gas exchange at the wound site. The distribution range of the tensile strength of the dressings was 9-12 Kpa, and the tensile strain was between 60-80%, providing sufficient mechanical support during wound healing. The dressings could absorb 4-8 times their own weight in solution and could rapidly absorb wound exudates from wet wounds. The nanofibers formed ionic crosslinked hydrogel after absorbing exudates, maintaining the moist condition. It formed a hydrogel-nanofiber composite structure with un-gelled nanofibers and combined the photocrosslinking network to maintain a stable structure at the wound location. The in vitro cell culture assay indicated that the dressings had excellent cell cytocompatibility, and the addition of SF contributed to cell proliferation and wound healing. The in situ deposited nanofiber dressings had excellent potential in the urgent treatment of emergency wounds.

Synergetic effects of hybrid steel and recycled tyre polymer fibres on workability, mechanical strengths and toughness of concrete

Recycled tyre polymer fibre (RTPF) has been considered an eco-friendly and promising alternative to traditional polymer fibres to enhance the engineering behaviours of concrete. This paper presents an experimental study to explore the synergetic effects of hybrid steel fibre (SF, 0.5–1.5 vol%) and RTPF (0.1–0.4 vol%) in tailoring the workability and mechanical properties of concrete, including slump, compressive and splitting tensile strengths, flexural toughness and load-deflection response. The results showed that the addition of either SF or RTPF lead to a decrease in the workability of concrete by 28.3%–81.2%. In contrast, the increasing content of SF from 0.5 vol% to 1.0 vol% and RTPF from 0.1 vol% to 0.2 vol% would enhance the average strengths and flexural toughness of concrete. In addition, the optimal content of SF and RTPF is 1.0 vol% and 0.2 vol%, respectively, which can promote the average compressive strength of plain concrete by up to 13.2 %. The microstructural analysis further revealed the synergetic effects of hybrid SF and RTPF in controlling the micro-cracks of concrete, which would contribute to the higher energy absorption capacity of concrete. The results suggested that hybrid SF and RTPF hold promise as sustainable alternatives to synthetic fibres in full-scale structural applications.

Optimization Based on Toughness and Splitting Tensile Strength of Steel-Fiber-Reinforced Concrete Incorporating Silica Fume Using Response Surface Method.

The greatest weakness of concrete as a construction material is its brittleness and low fracture energy absorption capacity until failure occurs. In order to improve concrete strength and durability, silica fume SF is introduced into the mixture, which at the same time leads to an increase in the brittleness of concrete. To improve the ductility and toughness of concrete, short steel fibers have been incorporated into concrete. Steel fibers and silica fume are jointly preferred for concrete design in order to obtain concrete with high strength and ductility. It is well-known that silica fume content and fiber properties, such as aspect ratio and volume ratio, directly affect the properties of SFRCs. The mixture design of steel-fiber-reinforced concrete (SFRC) with SF addition is a very important issue in terms of economy and performance. In this study, an experimental design was used to study the toughness and splitting tensile strength of SFRC with the response surface method (RSM). The models established by the RSM were used to optimize the design of SFRC in terms of the usage of optimal silica fume content, and optimal steel fiber volume and aspect ratio. Optimum silica fume content and fiber volume ratio values were determined using the D-optimal design method so that the steel fiber volume ratio was at the minimum and the bending toughness and splitting tensile strength were at the maximum. The amount of silica fume used as a cement replacement, aspect ratio, and volume fraction of steel fiber were chosen as independent variables in the experiment. Experimentally obtained mechanical properties of SFRC such as compression, bending, splitting, modulus of elasticity, toughness, and the toughness index were the dependent variables. A good correlation was observed between the dependent and independent variables included in the model. As a result of the optimization, optimum steel fiber volume was determined as 0.70% and silica fume content was determined as 15% for both aspect ratios.

Design, preparation, and characterization of silk fibroin/carboxymethyl cellulose wound dressing for skin tissue regeneration applications

AbstractSilk fibroin (SF) has been broadly applied in wound dressing fabrication because of its proper features for wound healing. In this work, we developed a carboxymethyl cellulose (CMC)/gelatin blend film with different concentrations of glycerol, and modified the optimized film with an SF layer through electrospinning process. Tensile strength and cell viability evaluation of blend films demonstrated that the glycerol content of 3% could be suitable as the substrate layer for the two‐layer wound dressing. The morphology of the blend film and electrospun nanofibers was obtained from scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). It concluded that structural changes had been occurred in both layers after cross‐linking with glutaraldehyde vapor. Further, it was shown that the mechanical properties of the two‐layer enhanced with the addition of SF. Moreover, the swelling ratio was higher than those of SF itself, due to the hydrophilic property of CMC/gelatin blend film. The biocompatibility of fibroblasts was investigated by MTT assay, and the coating showed an improvement in cell proliferation because of the cytocompatibility nature of SF. All results suggest that the prepared wound dressing could be a desirable candidate for wound healing applications.

Nutrient composition, bioactive components, functional, thermal and pasting properties of sweet potato flour‐incorporated protein‐enriched and low glycemic composite flour

The composite flour was produced with wheat flour, sweet potato flour, chick pea flour, and soybean flour (WF:SPF:CPF:SF) in the proportions of 100:0:0:0 (control), 0:100:0:0 (100% SPF), 70:10:10:10 (10% SPF), 60:20:10:10 (20% SPF), 50:30:10:10 (30% SPF), 40:40:10:10 (40% SPF), 30:50:10:10 (50% SPF), 20:60:10:10 (60% SPF), and 10:70:10:10 (70% SPF). The addition of SPF in blends leads to elevation in fiber, ash, minerals, and bioactive components. Protein content of flour blends was increased from 12.53% (Control) to 28.01% (10% SPF) due to addition of CPF and SF. The low glycemic functional properties of SPF reduced the estimated glycemic index of flour blends from 73.87 (Control) to 50.54 (70% SPF). The pasting temperature of flour blends was higher, whereas peak viscosity, break down viscosity, final viscosity, set back viscosity, and peak time were lower than control sample. The thermal properties were significantly higher in composite flours containing SPF than control. The prepared composite flour with 70% SPF, 10% WF, 10% CPF, and 10% SF was suitable for the development of protein enriched and low glycemic functional food. Novelty impact statement The present study investigates the use of under exploited sweet potato tubers for the development of composite flour having low glycemic index and enriched in protein content with the addition of chick pea and soy flour. The protein content was increased from 12.53% to 28.01%, and glycemic index was reduced from of 73.87 to 50.54 for sweet potato-based composite flour in comparison with the control. Composite flour also found rich in fiber, ash, microelements, bioactive compounds, and antioxidant activity. The composite flour enriched in protein content, bioactive compounds with reduced glycemic index could be used to develop functional food products for the management of the life style diseases.

Preparation of Silk Fibroin Nanofiber Scaffold and Its Application in Tendon-Bone Healing and Sports Rehabilitation

ABSTRACTIn this work, polylactic acid/polycaprolactone/silk fibroin (PLA/PCL/SF) nanofiber scaffolds with different mass ratios were prepared by electrospinning technology. The morphology and structure of the nanofiber scaffold were characterized with the scanning electron microscope (SEM), and its porosity and adsorption were tested using the Fourier transform infrared spectrometer (FTIR). 24 New Zealand white rabbits were rolled into control group (n = 8, with autologous tendons) and experimental group (n = 16) randomly. The PLA/PCL/SF nanofiber scaffolds were adopted to wrap autologous tendons to establish extra-articular models. Tendon-bone healing was evaluated six weeks after surgery through histological and biomechanical tests, and the related gene expressions in tissue cells were detected. It turned out that mass ratio of PLA/PCL and SF components had a considerable impact on the morphology of the nanofiber scaffold. The surface of nanofiber with a mass ratio of 3:1 was distributed with dense pores. As the content of SF increased, the porosity and adsorption of the nanofiber scaffold gradually decreased. Moreover, the experimental results suggested that the addition of SF improved the hydrophilicity of PLA/PCL/SF scaffold, which was beneficial to the adhesion and proliferation of NIH/3T3 (a mouse embryonic fibroblast cell line established by the National Institutes of Health (NIH)). In addition, histological observation results showed that the width of the tendon-bone interface (TBI) of rabbits in control group was still relatively large at the 6th week after the surgery, with poor healing effect and disordered collagen arrangement. The widths of the TBI of the material group and rehabilitation group were substantially narrower relative to that in control group, and the collagen was arranged regularly. It was suggested that the healing effects between tendon and bone in material group and rehabilitation group were accelerated, and the effect in the rehabilitation group was superior to that of material group, indicating that rehabilitation exercise could organize the negative effects of training in postoperative rehabilitation training and promote the healing between tendons and bones.

Research on the fire safety effect of thermoplastic polyurethane elastomer based on sodium fumarate

AbstractSodium fumarate (SF, C4H3NaO4), as a low‐cost and environment‐friendly additive, has been applied as the fire safety agent to investigate the flame retardancy and smoke suppression property in thermoplastic polyurethane elastomer (TPU). A series of tests were carried out, including limiting oxygen index (LOI), cone calorimeter test (CCT), smoke density test (SDT), and thermogravimetric/Fourier transform infrared spectroscopy (TG‐IR). The results proved that the addition of SF can significantly improve the fire safety property of TPU. Remarkably, in the case of the sample containing 2.0 wt% SF, LOI was raised up to 27.5 compared with 21.0 of pure TPU. The CCT results showed that pHRR, THR, TSR, and SF values decreased by 60.1%, 17.0%, 44.6%, and 66.4%, respectively, while the residual mass increased from 3.0% to 12.3% compared with pure TPU. The digital photographs displayed a more compact and intense carbon layer after the addition of SF. The SDT results indicated SF has increased the luminous flux and reduced Ds values, implying the improvement of the smoke suppression property of TPU. TG and TG‐IR results showed that the addition of SF has promoted the char forming process and reduced the release of CO2 and other volatile compounds. All results of tests illustrated that SF has considerable fire safety effect on TPU. Through the analysis of the results of this experiment, it will make a significance in the aspect of fire safety of polymer.

Soybean by-products and modified cassava starch for improving alveolar structure and quality characteristics of gluten-free bread

There is a global trend towards assuring more sustainable application of ingredients in food development, with emphasis in the nutrients recovering from agro-industrial by-products. Soybean extruded–expelled meal (SF) was explored to take an advantage from its nutrients; and its behaviour with pregelatinised cassava starch (PGS) and hydration levels (WC) as a contribution to technological improvement in gluten-free (GF) bread-making. The aim of this work was to study the effects of different levels of SF, PGS and WC on alveolar structure and final quality characteristics of GF bread formulation. A Box–Behnken experimental design and surface response methodology were applied. The final quality of GF breads was significantly affected by the addition of SF, PGS and WC, being the SF and WC the components with major impact. Lower levels of PGS and SF showed higher specific loaf volume with a softer crumb, faster recuperation of resilience and springiness, and less susceptibility to being disintegrated. The colour intensity and the uniformity of the alveolar crumb structure were enhanced by SF addition. Optimisation carried out to improve the physical and textural characteristics of bread, rendered a formulation with PGS 15.0 g × 100 g−1, SF 6.0 g × 100 g−1 and WC 160 g × 100 g−1. A size portion of GF bread (50 g) would increase 1.4- and 3.7-fold the protein and fibre intake, respectively. The addition SF and PGS with the adequate hydration level is promising for producing GF bread with an improved technological and nutritional profile, and could be useful to add value to an industrial by-product and reduce manufacturing cost.

Gas foaming of electrospun poly(L-lactide-co-caprolactone)/silk fibroin nanofiber scaffolds to promote cellular infiltration and tissue regeneration

Electrospun nanofibers emulate extracellular matrix (ECM) morphology and architecture; however, small pore size and tightly-packed fibers impede their translation in tissue engineering. Here we exploited in situ gas foaming to afford three-dimensional (3D) poly(L-lactide-co-ε-caprolactone)/silk fibroin (PLCL/SF) scaffolds, which exhibited nanotopographic cues and a multilayered structure. The addition of SF improved the hydrophilicity and biocompatibility of 3D PLCL scaffolds. Three-dimensional scaffolds exhibited larger pore size (38.75 ± 9.78 μm2) and high porosity (87.1% ± 1.5%) than that of their 2D counterparts. 3D scaffolds also improved the deposition of ECM components and neo-vessel regeneration as well as exhibited more numbers of CD163+/CCR7+ cells after 2 weeks implantation in a subcutaneous model. Collectively, 3D PLCL/SF scaffolds have broad implications for regenerative medicine and tissue engineering applications.

Permeability of self-compacting concrete made with recycled concrete aggregates and Portland cement-fly ash-silica fume binder

Permeability properties of self-compacting concrete (SCC) made with fine recycled concrete aggregates (FRCA), coarse recycled concrete aggregates (CRCA), and Portland cement-fly ash-silica fume binder are reported. Fresh and permeability properties of various SCC mixes were assessed. The results indicate that the increase in content of fine and coarse recycled concrete aggregates (RCA) in SCC tends to deteriorate the workability and permeability properties. The compressive strength also decreased with the inclusion of RCA. The substitution of 50% CRCA and 25% FRCA in SCC mix shows marginal decrease in hardened SCC properties as compared to SCC made with fine and coarse natural aggregates. Further, increase in FRCA content in SCC mix deteriorated the compressive strength and permeability properties. Furthermore, the addition of SF at 10% by weight of ordinary Portland cement was able to compensate the loss of permeability properties even for 50% substitution of both FRCA and CRCA.

Influence of a Stepped Heat Curing on the Performance of High-Strength Portland Pozzolana Cement–Based Mortars

Abstract In this study, the effects of a stepped heat curing regime originally developed for the Indian conditions on the performance properties of high strength cementitious mortars (HSCMs) containing portland pozzolana cement (PPC) were evaluated. Six mixtures were cast without and with heat curing, including two control mixtures (CM-NC and CM-HC), two silica fume mixtures (SF-NC and SF-HC), and two rice husk ash mixtures (RHA-NC and RHA-HC). Results indicated that stepped heat curing improved the 7-day strength of all mixtures substantially, but mixtures were unable to maintain very high strength levels up to 28 days. The 28-day strengths of heat-cured specimens were comparable with that of the respective normal water-cured specimens. The trends obtained for flexural, impact, and dynamic split tensile strengths supported the compressive strength trends. The durability properties of mixtures were affected to some extent by the use of high temperature for longer duration despite certain improvements in their matrices. Thus, longer durations of high temperature of 200°C up to 48 h should be avoided for HSCMs containing PPC. Under normal water and heat curing, the addition of SF and RHA lowered the early-age compressive strength of HSCMs, whereas at 28 days, their strength and durability improved. In addition, the performances of SF and RHA mixtures were comparable to each other.

The effect of silica fume inclusion on the properties of recycled concrete aggregate- containing concrete

Protecting the environment against the hazards of construction and demolishing (C&D) wastes is crucial. Elimination of C&D wastes by using them as recycled concrete aggregates (RCA) within the manufacture of new concretes is a promising solution for this problem. Since RCA coming from demolished structures have poor qualities, overall performance of new concrete should be monitored carefully. Without achieving a satisfactory strength performance, manufacturing concretes with RCA could not be widely accepted in construction sector. This study investigates the effects of silica fume, which is an effective pozzolanic material, on the properties of concrete mixtures made with 50%RCA as a replacement to quarried aggregates. RCA used was obtained from a 25-years old public building in Nicosia that was structurally failed and demolished. Results obtained indicated a 12.3% water demand increase for obtaining the targeted slump when SF was added in fresh concrete. The increase in compressive strength of concrete with SF in 28 days was 1.5%, where this increase was recorded as 8.1% at 90 days, yielding more than 65MPa strength. Also, addition of SF was observed to improve flexural strength of concrete samples up to a 4.3% at the age of 28 days, enabling the manufacture concrete mixtures apt for structural use.

Inclusion of Soluble Fiber in the Gestation Diet Changes the Gut Microbiota, Affects Plasma Propionate and Odd-Chain Fatty Acids Levels, and Improves Insulin Sensitivity in Sows.

The transition from pregnancy to lactation is characterized by a progressive decrease in insulin sensitivity. Propionate increases with dietary fiber consumption and has been shown to improve insulin sensitivity. Recent studies suggest that plasma odd-chain fatty acids [OCFAs; pentadecanoic acid (C15:0) and heptadecanoic acid (C17:0)] that inversely correlated with insulin resistance are synthesized endogenously from gut-derived propionate. The present study investigated the effects of soluble fiber during gestation on gut microbiota, plasma non-esterified fatty acids and insulin sensitivity in sows. Sows were allocated to either control or 2.0% guar gum plus pregelatinized waxy maize starch (SF) dietary treatment during gestation. The SF addition changes the structure and composition of gut microbiota in sows. Genus Eubacterium increased by SF addition may promote intestinal propionate production. Moreover, the dietary SF increased circulating levels of plasma OCFAs, especially C17:0. The SF-fed sows had a higher insulin sensitivity and a lower systemic inflammation level during perinatal period. Furthermore, the plasma C15:0 and C17:0 was negatively correlated with the area under curve of plasma glucose after meal and plasma interleukin-6. In conclusion, dietary SF improves insulin sensitivity and alleviates systemic inflammation in perinatal sows, potentially related to its stimulating effect on propionate and OCFAs production.

A bio-psycho-social approach for frailty amongst Singaporean Chinese community-dwelling older adults \u2013 evidence from the\xa0Singapore Longitudinal Aging Study

BackgroundFew empirical studies support a bio-psycho-social conceptualization of frailty. In addition to physical frailty (PF), we explored mental (MF) and social (SF) frailty and studied the associations between multidimensional frailty and various adverse health outcomes.MethodsCross-sectional and longitudinal analyses were conducted using data from a population-based cohort (SLAS-1) of 2387 community-dwelling Singaporean Chinese older adults. Outcomes examined were functional and severe disability, nursing home referral and mortality. PF was defined by shrinking, weakness, slowness, exhaustion and physical inactivity, 1–2 = pre-frail, 3–5 = frail; MF was defined by ≥1 of cognitive impairment, low mood and poor self-reported health; SF was defined by ≥2 of living alone, no education, no confidant, infrequent social contact or help, infrequent social activities, financial difficulty and living in low-end public housing.ResultsThe prevalence of any frailty dimension was 63.0%, dominated by PF (26.2%) and multidimensional frailty (24.2%); 7.0% had all three frailty dimensions. With a few exceptions, frailty dimensions share similar associations with many socio-demographic, lifestyle, health and behavioral factors. Each frailty dimension varied in showing independent associations with functional (Odds Ratios [ORs] = 1.3–1.8) and severe disability prevalence at baseline (ORs = 2.2–7.3), incident functional disability (ORs = 1.1–1.5), nursing home referral (ORs = 1.5–3.4) and mortality (Hazard Ratios = 1.3–1.5) after adjusting for age, gender, medical comorbidity and the two other frailty dimensions. The addition of MF and SF to PF incrementally increased risk estimates by more than 2 folds.ConclusionsThis study highlights the relevance and utility of PF, MF and SF individually and together. Multidimensional frailty can better inform policies and promote the use of targeted multi-domain interventions tailored to older adults’ frailty statuses.

Osteogenic Differentiation of Mesenchymal Stem Cells with Silica-Coated Gold Nanoparticles for Bone Tissue Engineering.

Multifunctional nanofibrous scaffolds for effective bone tissue engineering (BTE) application must incorporate factors to promote neovascularization and tissue regeneration. In this study, silica-coated gold nanoparticles Au(SiO2) were tested for their ability to promote differentiation of human mesenchymal stem cells (hMSCs) into osteoblasts. Biocompatible poly-ε-caprolactone (PCL), PCL/silk fibroin (SF) and PCL/SF/Au(SiO2) loaded nanofibrous scaffolds were first fabricated by an electrospinning method. Electrospun nanofibrous scaffolds were characterized for fiber architecture, porosity, pore size distribution, fiber wettability and the relevant mechanical properties using field emission scanning electron microscopy (FESEM), porosimetry, determination of water contact angle, measurements by a surface analyzer and tabletop tensile-tester measurements. FESEM images of the scaffolds revealed beadless, porous, uniform fibers with diameters in the range of 164 ± 18.65 nm to 215 ± 32.12 nm and porosity of around 88–92% and pore size distribution around 1.45–2.35 µm. Following hMSCs were cultured on the composite scaffolds. Cell-scaffold interaction, morphology and proliferation of were analyzed by FESEM analysis, MTS (3-(4,5-dimethyl thiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt) and CMFDA (5-choromethyl fluorescein acetate) dye assays. Osteogenic differentiation of MSCs into osteogenic cells were determined by alkaline phosphatase (ALP) activity, mineralization by alizarin red S (ARS) staining and osteocalcin expression by immunofluorescence staining. The results revealed that the addition of SF and Au(SiO2) to PCL scaffolds enhanced the mechanical strength, interconnecting porous structure and surface roughness of the scaffolds. This, in turn, led to successful osteogenic differentiation of hMSCs with improved cell adhesion, proliferation, differentiation, mineralization and expression of pro-osteogenic cellular proteins. This provides huge support for Au(SiO2) as a suitable material in BTE.