Swelling of acetylated wood in organic liquids

To investigate the affinity of acetylated wood for organic liquids, Yezo spruce wood specimens were acetylated with acetic anhydride, and their swelling in various liquids were compared to those of untreated specimens. The acetylated wood was rapidly and remarkably swollen in aprotic organic liquids such as benzene and toluene in which the untreated wood was swollen only slightly and/or very slowly. On the other hand, the swelling of wood in water, ethylene glycol and alcohols remained unchanged or decreased by the acetylation. Consequently the maximum volume of wood swollen in organic liquids was always larger than that in water. The effect of acetylation on the maximum swollen volume of wood was greater in liquids having smaller solubility parameters. The easier penetration of aprotic organic liquids into the acetylated wood was considered to be due to the scission of hydrogen bonds among the amorphous wood constituents by the substitution of hydroxyl groups with hydrophobic acetyl groups.Comment: to be published in J Wood Science (Japanese wood research society

Invasive mechanical ventilation in cancer patients: prior non-invasive ventilation is a poor prognostic factor

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Influence of Material Properties on Rate of Resorption of Two Bone Graft Materials after Sinus Lift Using Radiographic Assessment

. Purpose. The aim of this study was to investigate the influence of chemical and physical properties of two graft materials on the rate of resorption. Materials and Methods. Direct sinus graft procedure was performed on 22 patients intended for implant placement. Two types of graft materials were used (Bio-Oss and Cerabone) and after 8 months healing time the implants were inserted. Radiographic assessment was performed over the period of four years. Particle size, rate of calcium release, and size and type of crystal structure of each graft were evaluated. Results. The average particle size of Bio-Oss (1 mm) was much smaller compared to Cerabone (2.7 mm). The amount of calcium release due to dissolution of material in water was much higher for Bio-oss compared to Cerabone. X-ray image analysis revealed that Bio-Oss demonstrated significantly higher volumetric loss (33.4 ± 3.1%) of initial graft size compared to Cerabone (23.4 ± 3.6%). The greatest amount of vertical loss of graft material volume was observed after one year of surgery. Conclusion. The chemical and physical properties of bone graft material significantly influence resorption rate of bone graft materials used for sinus augmentation

Influence of Material Properties on Rate of Resorption of Two Bone Graft Materials after Sinus Lift Using Radiographic Assessment

Purpose. The aim of this study was to investigate the influence of chemical and physical properties of two graft materials on the rate of resorption. Materials and Methods. Direct sinus graft procedure was performed on 22 patients intended for implant placement. Two types of graft materials were used (Bio-Oss and Cerabone) and after 8 months healing time the implants were inserted. Radiographic assessment was performed over the period of four years. Particle size, rate of calcium release, and size and type of crystal structure of each graft were evaluated. Results. The average particle size of Bio-Oss (1 mm) was much smaller compared to Cerabone (2.7 mm). The amount of calcium release due to dissolution of material in water was much higher for Bio-oss compared to Cerabone. X-ray image analysis revealed that Bio-Oss demonstrated significantly higher volumetric loss (33.4 ± 3.1%) of initial graft size compared to Cerabone (23.4 ± 3.6%). The greatest amount of vertical loss of graft material volume was observed after one year of surgery. Conclusion. The chemical and physical properties of bone graft material significantly influence resorption rate of bone graft materials used for sinus augmentation

Experimental Investigation and Large-Eddy Simulation of the Turbulent Flow past a Smooth and Rigid Hemisphere

Computations carried out on the German Federal Top-Level Computer SuperMUC at LRZ Munich under the contract number pr84na.International audienceThe objective of the present paper is to provide a detailed experimental and numerical investigation on the turbulent flow past a hemispherical obstacle (diameter D). For this purpose, the bluff body is exposed to a thick turbulent boundary layer of the thickness δ = D/2 at Re = 50,000. In the experiment this boundary layer thickness is achieved by specific fences placed in the upstream region of the wind tunnel. A detailed measurement of the upstream flow conditions by laser-Doppler and hot-film probes allows to mimic the inflow conditions for the complementary large-eddy simulation of the flow field using a synthetic turbulence inflow generator. These clearly defined boundary and operating conditions are the prerequisites for a combined experimental and numerical investigation of the flow field relying on the laser-Doppler anemometry and a finite-volume Navier-Stokes solver for block-structured curvilinear grids. The results comprise an analysis on the unsteady flow features observed in the vicinity of the hemisphere as well as a detailed discussion of the time-averaged flow field. The latter includes the mean velocity field as well as the Reynolds stresses. Owing to the proper description of the oncoming flow and supplementary numerical studies guaranteeing the choice of an appropriate grid and subgrid-scale model, the results of the measurements and the prediction are found to be in close agreement

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Migration of dendritic cells to the lymph nodes and its enhancement to drive anti-tumor responses.

Better prognoses associated with increased T cell infiltration of tumors, as seen with chimeric antigen receptor (CAR) T cell therapies and immune checkpoint inhibitors, portray the importance and potential of the immune system in controlling tumors. This has rejuvenated the field of cancer immunotherapy leading to an increasing number of immunotherapies developed for cancer patients. Dendritic Cells (DCs) vaccines represent an appealing option for cancer immunotherapy since DCs have the ability to circumvent tolerance to tumors by its adjuvant properties and to induce memory T cells that can become persistent after initial tumor clearance to engage potential metastatic tumors. In the past, DC-based cancer vaccines have elicited only poor clinical response in cancer patients, which can be attributed to complex and a multitude of issues associated with generation, implementing, delivery of DC vaccine and their potential interaction with effector cells. The current review mainly focuses on migration/trafficking of DCs, as one of the key issues that affect the success of DC-based cancer vaccines, and discusses strategies to enhance it for cancer immunotherapy. Additionally, impact of maturation, route of DC delivery and negative effects of tumor microenvironment (TME) on DC homing to LN are reviewed. Moreover, strategies to increase the expression of genes involved in Lymph node homing, preconditioning of the vaccination site, enhancing lymph node ability to attract and receive DCs, while limiting negative impact of TME on DC migration are discussed