1,903 research outputs found

    Evaluation of 3D printed PCL/PLGA/beta-TCP versus collagen membranes for guided bone regeneration in a beagle implant model

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    Here, we compared 3D-printed polycaprolactone/poly(lactic-co-glycolic acid)/beta-tricalcium phosphate (PCL/PLGA/beta-TCP) membranes with the widely used collagen membranes for guided bone regeneration (GBR) in beagle implant models. For mechanical property comparison in dry and wet conditions and cytocompatibility determination, we analyzed the rate and pattern of cell proliferation of seeded fibroblasts and preosteoblasts using the cell counting kit-8 assay and scanning electron microscopy. Osteogenic differentiation was verified using alizarin red S staining. At 8 weeks following implantation in vivo using beagle dogs, computed tomography and histological analyses were performed after sacrifice. Cell proliferation rates in vitro indicated that early cell attachment was higher in collagen than in PCL/PLGA/beta-TCP membranes; however, the difference subsided by day 7. Similar outcomes were found for osteogenic differentiation, with approximately 2.5 times greater staining in collagen than PCL/PLGA/beta-TCP, but without significant difference by day 14. In vivo, bone regeneration in the defect area, represented by new bone formation and bone-to-implant contact, paralleled those associated with collagen membranes. However, tensile testing revealed that whereas the PCL/PLGA/beta-TCP membrane mechanical properties were conserved in both wet and dry states, the tensile property of collagen was reduced by 99% under wet conditions. Our results demonstrate in vitro and in vivo that PCL/PLGA/beta-TCP membranes have similar levels of biocompatibility and bone regeneration as collagen membranes. In particular, considering that GBR is always applied to a wet environment (e.g. blood, saliva), we demonstrated that PCL/PLGA/beta-TCP membranes maintained their form more reliably than collagen membranes in a wet setting, confirming their appropriateness as a GBR membrane.11109Ysciescopu

    Investigation of the Antiasthmatic Properties of Ethanol Extract of Callophyllis japonica in Mice

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    Purpose: To determine whether an ethanol extract from Callophyllis japonica (C. japonica) could attenuate indices of airway inflammation in a murine model of ovalbumin (OVA)-induced asthma.Methods: The free radical scavenging activity of the C. japonica ethanol extracts (CJE) were investigated using an electron spin resonance (ESR) system. To make develop animal model of asthma, mice were sensitized and challenged with OVA.Results: CJE exhibited considerable scavenging activity of 71.08 ± 0.73, 79.11 ± 6.04%, 75.95 ± 7.01%, and 48.56 ± 5.96% of DPPH, alkyl, superoxide, and hydroxyl radicals, respectively. The successive intraperitoneal administration of CJE reduced the number of eosinophils in bronchoalveolar lavage (BAL) fluid, development of airway hyperresponsiveness (AHR), an increase in pulmonary Th2 cytokines, and allergen-specific immunoglobulin E (IgE).Conclusion: Administration of CJE markedly alleviates all indices of airway inflammation. This study provides evidence that CJE plays a critical role in the amelioration of the pathogenetic process of allergic asthma in mice.Keywords: Asthma, Phenolic contents, Free radical scavenging, Airway hyper-responsiveness, Cytokines, Immunoglobulin

    Magnetic Origin of Giant Magnetoelectricity in Doped Y-type Hexaferrite Ba0.5Sr1.5Zn2(Fe1-xAlx)(12)O-22

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    We investigated site-specific magnetic behaviors of multiferroic Ba0.5Sr1.5Zn2(Fe1-xAlx)(12)O-22 using Fe L-2,L-3-edge x-ray magnetic circular dichroism. The Al dopants mostly replace the Fe3+ ions at octahedral (O-h) sites, which contribute unquenched angular momenta through off-centering displacements. This replacement greatly reduces the magnetic anisotropy energy to change the magnetic order from a helical to a heliconical type with enhanced magnetoelectric susceptibility (alpha(ME)). The tetrahedral (T-d) Fe sites exhibit magnetic hysteresis distinguishable from that of the O-h sites, especially at low magnetic fields. These results provide essential clues for the heliconical order with a giant aME and multibit memory effects in the Al-doped Y-type hexaferrite.open1178sciescopu

    Flexible IZO/Ag/IZO/Ag multilayer electrode grown on a polyethylene terephthalate substrate using roll-to-roll sputtering

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    We investigated the optical, electrical, structural, and surface properties of roll-to-roll [R2R] sputter-grown flexible IZO/Ag/IZO/Ag [IAIA] multilayer films on polyethylene terephthalate substrates as a function of the top indium zinc oxide [IZO] thickness. It was found that the optical transmittance of the IAIA multilayer was significantly influenced by the top IZO layer thickness, which was grown on identical AIA multilayers. However, the sheet resistance of the IAIA multilayer was maintained between the range 5.01 to 5.1 Ω/square regardless of the top IZO thickness because the sheet resistance of the IAIA multilayer was mainly dependent on the thickness of the Ag layers. Notably, the optimized IAIA multilayer had a constant resistance change (ΔR/R0) under repeated outer bending tests with a radius of 10 mm. The mechanical integrity of the R2R-sputtered IAIA multilayer indicated that hybridization of an IZO and Ag metal layer is a promising flexible electrode scheme for the next-generation flexible optoelectronics

    Clothing insulation and temperature, layer and mass of clothing under comfortable environmental conditions

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    This study was designed to investigate the relationship between the microclimate temperature and clothing insulation (Icl) under comfortable environmental conditions. In total, 20 subjects (13 women, 7 men) took part in this study. Four environmental temperatures were chosen: 14??C (to represent March/April), 25??C (May/June), 29??C (July/August), and 23??C (September/October). Wind speed (0.14ms-1) and humidity (45%) were held constant. Clothing microclimate temperatures were measured at the chest (Tchest) and on the interscapular region (Tscapular). Clothing temperature of the innermost layer (Tinnermost) was measured on this layer 30 mm above the centre of the left breast. Subjects were free to choose the clothing that offered them thermal comfort under each environmental condition. We found the following results. 1) All clothing factors except the number of lower clothing layers (Llower), showed differences between the different environmental conditions (P<0.05). The ranges of Tchest were 31.6 to 33.5??C and 32.2 to 33.4??C in Tscapular. The range of Tinnermost was 28.6 to 32.0??C. The range of the upper clothing layers (Lupper) and total clothing mass (Mtotal) was 1.1 to 3.2 layers and 473 to 1659 g respectively. The range of Icl was 0.78 to 2.10 clo. 2) Post hoc analyses showed that analysis of Tinnermost produced the same results as for that of Icl. Likewise, the analysis of Lupper produced the same result as the analysis of the number of total layers (Ltotal) within an outfit. 3) Air temperature (ta) had positive relationships with Tchest and Tscapular and with Tinnermost but had inverse correlations with Icl, Mtotal, Lupper and Ltotal. Tchest, Tscapular, and Tinnermost increased as ta rose. 4) Icl had inverse relationships with Tchest and Tinnermost, but positive relationships with Mtotal, Lupper and Ltotal. Icl could be estimated by Mtotal, Lupper, and Tscapular using a multivariate linear regression model. 5) Lupper had positive relationships with Icl and Mtotal, but Llower did not. Subjects hardly changed Llower under environmental comfort conditions between March and October. This indicates that each of the Tchest, Mtotal, and Lupper was a factor in predicting Icl. Tinnermost might also be a more influential factor than the clothing microclimate temperature.open1

    Allah n'est pas obligé d'Ahmadou Kourouma: Une gymnastiquie langagière

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    Avec seulement quatre romans publiés en vingt-quatre ans, Ahmadou Kourouma s'est imposé comme l'un des écrivains les plus importants du conti- nent africain. Dans ses romans: Les soleils des Indépendances (1976), Monné, outrages et défis (1990), En attendant le vote des bêtes sauvages (1999) et Allah n'est pas obligé (2000), l'écrivain ivoirien dénonce les souffrances de l' Afrique noire. Il les dénonce avec les yeux des Africains et les décrit dans une langue calquée sur la leur. En effet, son style étonne, choque, séduit. Kourouma ne s'est pas contenté de «penser la langue»comme tout autre écrivain francophone; son oeuvre ne témoigne pas seulement d'une sorte d'hétérogénéité langagière comme c'est le cas en général chez les écrivains qui vivent le conflit des langues et des cultures; il est allé plus loin. Sa grande innovation comme dit si bien l'un des chercheurs, «réside dans le fait de proposer une oeuvre dont le protagoniste est à tout considérer le style-oui, le style malinké transposé en français

    Umbilical hernia rupture with evisceration of omentum from massive ascites: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>The incidence of hernias is increased in patients with alcoholic liver disease with ascites. To the best of our knowledge, this is the first report of an acute rise in intra-abdominal pressure from straining for stool as the cause of a ruptured umbilical hernia.</p> <p>Case presentation</p> <p>An 81-year-old Caucasian man with a history of alcoholic liver disease presented to our emergency department with an erythematous umbilical hernia and clear, yellow discharge from the umbilicus. On straining for stool, after initial clinical assessment, our patient noted a gush of fluid and evisceration of omentum from the umbilical hernia. An urgent laparotomy was performed with excision of the umbilicus and devitalized omentum.</p> <p>Conclusion</p> <p>We report the case of a patient with a history of alcoholic liver disease with ascites. Ascites causes a chronic increase in intra-abdominal pressure. A sudden increase in intra-abdominal pressure, such as coughing, vomiting, gastroscopy or, as in this case, straining for stool can cause rupture of an umbilical hernia. The presence of discoloration, ulceration or a rapid increase in size of the umbilical hernia signals impending rupture and should prompt the physician to reduce the intra-abdominal pressure.</p
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