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Ternesite is synthesized through sintering a mixture of CaCO3, SiO2, and CaSO4 in a molar ratio of 4:2:1. Ternesite has a hydration rate between ye'elimite and belite in an aluminum-containing environment, and is considered to be a new material that can be used to enhance the performance of calcium sulphoaluminate cements. This experiment investigated the influence of different particle sizes of SiO2 on ternesite formation. Controlled partial pressure sintering was employed within the temperature range from 1100 °C to 1200 °C, with a 72 h incubation period. The highest purity of ternesite in the samples reached 99.47% (500 nm SiO2 sample). The analysis results from scanning electron microscopy and an energy dispersive spectrometer indicated that the particle size of SiO2 exerted a significant influence on the formation of ternesite. In the preparation of ternesite from 10 μm particle size SiO2, traces of calcium silicate were found in the product. The results of a thermal analysis further demonstrated significant distinctions in the thermal stability of ternesite prepared with SiO2 of different particle sizes. Additionally, the crystallinity of ternesite was influenced by the particle size of SiO2, consequently impacting the hydration performance of ternesite–calcium sulphoaluminate cement. [ABSTRACT FROM AUTHOR]

Four weld metals respectively named LOLT (Low oxygen low titanium), LOHT (Low oxygen high titanium), HOLT (High oxygen low titanium), HOHT (High oxygen high titanium) with varying Ti and O additions were prepared by laboratory high heat input welding test. The effects of Ti, B and O on microstructure and impact toughness of these weld metals were investigated. The results show that with 205 kJ/cm high heat input, the contents of O and Ti in LOLT were appropriate, and a large number of cross-distributed acicular ferrite were formed, which improved the impact toughness; with the increasing Ti addition, granular bainite was formed in LOHT, which deteriorated its impact toughness. Compared with LOLT, the number of inclusions in HOLT was increased due to the higher O addition. Meanwhile, coarse grain boundary ferrite (GBF) was formed at prior austenite grain boundary because the interaction of B to the excess O prevented its segregation at austenite grain boundary, which resulted in the decrease of weld metal impact toughness. However, as Ti addition increased again, the number of inclusions in HOHT did not change much but GBF was not formed, which improved the impact toughness. [ABSTRACT FROM AUTHOR]

In this present work, during high heat input welding of the weld metal, different types of Mn-depleted zones were achieved by different cooling rates. The effects of cooling rates on Mn-depleted zone formation and acicular ferrite (AF) transformation were analyzed. The Mn-depleted zone around the inclusions, as well as the interface concentration of Mn atoms, are found to be significantly different with different cooling rates. When the cooling rate is 10 °C/s, the interface concentration of Mn atoms around the inclusions is the lowest, the area of Mn-depleted zone is the smallest, and the proportion of AF in the weld metal is the highest. As the cooling rate decreases further, the interface concentration of Mn begins to rise, the area of the Mn-depleted zone gradually expands, and the proportion of AF decreases. However, when the cooling rate reaches 100 °C/s, only a very small amount of MnS precipitates, no Mn-depleted zone forms around the inclusions, and acicular ferrite cannot be produced effectively in the weld metal. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to examine the prevalences of CVD, CVD risk factors. and health behaviors among cancer survivor‐spouse dyads, assess how these prevalences differ by role (survivor vs spouse) and gender, and report congruences in health behaviors between survivors and their spouses. Methods: We identified 1026 survivor‐spouse dyads from the 2010‐2015 Medical Expenditure Panel Survey. We used weighted multivariable logistic and linear regressions to analyze the data related to CVD, CVD risk factors, and health behaviors. Results: Survivors and spouses reported high prevalences of CVD and CVD risk factors but low engagement in healthy behaviors, including non‐smoking, physical activity, and maintaining a healthy weight (proxy for healthy diet). Gender and role differences were significantly related to the prevalence of CVD, CVD risk factors, and health behaviors among survivors and spouses. From 39% to 88% of survivors and spouses were congruent in their current smoking status, physical activity engagement/disengagement, and BMI. Conclusion: Cancer survivors and spouses have high rates of CVD and CVD risk factors and poor engagement in healthful lifestyle behaviors. A high proportion of survivors and spouses were congruent in their current smoking status, physical activity engagement/disengagement, and BMI. Effective lifestyle interventions are needed for this high‐risk population. Couple‐focused interventions may be well‐suited for these dyads and warrant further study. Implications for Cancer Survivors: Both cancer survivors and their spouses need to be non‐moking, more physically active, and maintain normal BMI in order to reduce their high risk of CVD and CVD risk factors. [ABSTRACT FROM AUTHOR]

Three weld metals with different oxygen contents were developed. The influence of oxygen contents on the microstructure and impact toughness of weld metal was investigated through high heat input welding tests. The results showed that a large number of fine inclusions were formed and distributed randomly in the weld metal with oxygen content of 500 ppm under the heat input condition of 341 kJ/cm. Substantial cross interlocked acicular ferritic grains were induced to generate in the vicinity of the inclusions, primarily leading to the high impact toughness at low temperature for the weld metal. With the increase of oxygen content, the number of fine inclusions distributed in the weld metal increased and the grain size of intragranular acicular ferrites decreased, which enhanced the impact toughness of the weld metal. Nevertheless, a further increase of oxygen content would contribute to a great diminution of the austenitic grain size. Following that the fraction of grain boundary and the start temperature of transformation increased, which facilitated the abundant formation of pro-eutectoid ferrites and resulted in a deteriorative impact toughness of the weld metal. [ABSTRACT FROM AUTHOR]

We tested the ability of the axolotl (Ambystoma mexicanum) fibula to regenerate across segment defects of different size in the absence of intervention or after implant of a unique 8-braid pig small intestine submucosa (SIS) scaffold, with or without incorporated growth factor combinations or tissue protein extract. Fractures and defects of 10% and 20% of the total limb length regenerated well without any intervention, but 40% and 50% defects failed to regenerate after either simple removal of bone or implanting SIS scaffold alone. By contrast, scaffold soaked in the growth factor combination BMP-4/HGF or in protein extract of intact limb tissue promoted partial or extensive induction of cartilage and bone across 50% segment defects in 30%-33% of cases. These results show that BMP-4/HGF and intact tissue protein extract can promote the events required to induce cartilage and bone formation across a segment defect larger than critical size and that the long bones of axolotl limbs are an inexpensive model to screen soluble factors and natural and synthetic scaffolds for their efficacy in stimulating this process. [ABSTRACT FROM AUTHOR]

Collagens, especially Type I collagen, are the primary structural proteins in the body. They sustain mechanical bodily stresses, support different types of cells, and serve as anchors for various growth factors. The collagen-peptides produced when collagens are cleaved by enzymatic activities also exhibit potent biological activities. As highly biocompatible molecules with potent biological functions, the collagens have garnered wide interest as biomedical materials, in particular, for tissue repair and regeneration. This review first provides a brief introduction to collagen structure and classification, and then primarily focuses on the current development of collagen-based biomaterials, with emphasis on collagen-based scaffolding materials for tissue regeneration. [ABSTRACT FROM AUTHOR]

Background: Tissue breakdown in periodontitis is initiated by bacteria, such as Porphyromonas gingivalis, and is caused largely by host responses. Resolvins protect the host against acute inflammation by blocking the migration of polymorphonuclear neutrophils to initiate resolution. The effects of resolvins on human gingival fibroblasts (HGFs) are unknown. This study examines the effects of resolvin D1 on HGF survival and cytokine expression when treated with or without P. gingivalis supernatant. Methods: Cytotoxicity of resolvin D1 on HGFs with or without a toxic level of P. gingivualis supernatant was measured with lactate dehydrogenase assays. Cytokine arrays were performed on HGF-conditioned media treated with or without resolvin D1 and with or without P. gingivualis supernatant. Results: Resolvin D1 had no cytotoxic effects on HGFs at concentrations between 1 and 1,000 nM (all P> 0.05). Resolvin D1 (1,000 nM) significantly inhibited the toxic effects of 13.5% (v/v) P. gingivualis supernatant on HGFs (P = 0.002). Resolvin D1 significantly reduced the expression of interleu-kin (IL)-6 (P= 0.010) and monocyte chemoattractant protein (MCP)-1 (P = 0.04) in untreated fibroblasts. P. gingivualis (10%) supernatant significantly increased the expression levels of granulocyte-macrophage colony-stimulating factor (CSF), granulocyte CSF, growth-regulated oncogene (GRO), IL-5, IL-6, IL-7,IL-8, IL-10, MCP-1, MCP-2, MCP-3, and monokine induced by γ-interferon. Resolvin D1 significantly reduced the expression of GRO (P= 0.04), marginally reduced the levels of MCP-1 (P= 0.10), and marginally increased the levels of transforming growth factor (TGF)-β1 (P = 0.07) from HGFs treated with P. gingivualis supernatant. Conclusions: Resolvin D1 altered the cytotoxicity of P. gingivualis supernatant on HGFs. Resolvin D1 significantly reduced GRO, marginally reduced MCP-1, and marginally increased TGF-β1 from P. gingivualis-treated HGFs, which could alter the ability of P. gingivualis to induce inflammation. [ABSTRACT FROM AUTHOR]

Background: Members of the matrix metalloproteinase (MMP) family have been shown to be involved in periodontal disease. Risk factors for periodontal disease include tobacco smoking. Cigarette smoke condensate (CSC) is comprised of thousands of chemicals. Nicotine is one of the active components in tobacco. This study compares the effects of CSC and nicotine at the level in CSC on the collagen-degrading ability of human gingival fibroblasts (HGFs) and the expression of selected MMPs and tissue inhibitors of metalloproteinases (TIMPs). Methods: HGFs were seeded in six-well collagen-coated plates, exposed to 100 µg/mL (2.4 µg/mL nicotine) of CSC or 2.4 µg/mL nicotine for 3 days, and then collagen degradation was analyzed. After 3 days exposure to CSC or nicotine, the conditioned media from HGFs was collected and the membrane proteins were extracted for gelatin zymography and Western blot analyses. The mRNA levels of MMP-2, MMP-14, and TIMP-2 were measured by reverse transcription-polymerase chain reaction. Results: The CSC increased collagen degradation, and increased the levels of TIMP-2, MMP-14, and the active MMP-2 in the membrane extracts, and their mRNA levels. CSC also increased the level of active MMP-2 in the conditioned media. Nicotine at the level in CSC (2.4 µg/mL) had little influence on collagen degradation, as well as on the protein and mRNA levels of MMP-2, MMP-14, and TIMP-2. Conclusions: CSC may increase HGF-mediated collagen degradation by affecting membrane-associated MMPs and TIMPs. [ABSTRACT FROM AUTHOR]

We used an antibody array to compare the protein expression of matrix metalloproteinases (MMPs)-1, -2, -3, -8, -9, -10, and -13, as well as the tissue inhibitors of metalloproteinases (TIMPs)-1, -2, and -4 during blastema formation in amputated hindlimbs of regeneration-competent wild-type axolotls and stage-54 Xenopus, and regeneration-deficient short-toes axolotls and Xenopus froglets. Expression of MMP-9 and -2 was also compared by zymography. Both short-toes and froglet failed to up-regulate MMPs in a pattern comparable to the wild-type axolotl, suggesting that subnormal histolysis is at least in part responsible for the poor blastema formation characteristic of both short-toes and froglet. MMP levels were much lower in amputated stage-54 Xenopus limb buds than in the other animals, suggesting that blastema formation in these limb buds requires much less extracellular matrix degradation than in fully differentiated limbs. TIMP expression patterns followed the same trends as the MMP's in each group of animals. Developmental Dynamics 240:1127-1141, 2011. © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]