REDUCING WATER ENTRY IMPACT LOADS ON MARINE STRUCTURES BY SURFACE MODIFICATION

In this study, the effect of hydrophobicity in reducing the impact forces during the water entry of complex geometries has been demonstrated on bow flare slamming and wet deck slamming. Superhydrophobic surfaces with a contact angle of 1600 and a hysteresis of 30 which shows a wetting regime in the Cassie–Baxter state were obtained via a chemical coating. By conducting drop tests with a bow flare ship section model and a catamaran section model at various impact velocities, jet flows, water pileups and air cavities were compared between the hydrophilic and hydrophobic cases via high speed camera images. The impact loads acting on the test bodies under hydrophobic effects were also compared via strain gauge measurements. The rise time of the strain values was measured shorter with smaller magnitudes in the hydrophobic cases. The modification in the jet flow propagation affects the total impact force. The results showed that hydrophobicity modifies the water uprising characteristics and energy balances, and reduces the impact loads acting on marine structures during slamming events

The influence of post-fixation on visualising vimentin in the retina using immunofluorescence method

Background: Post-fixation of sections is especially required for cryostat sections of fresh frozen tissues. Vimentin is an intermediate filament in both fibrillary and non-fibrillary form, expressed in Müller’s cells and astrocytes of the retina. Our aim was to determine the best post-fixation method for visualising vimentin in archival mouse eyes. Materials and methods: We used an archival mouse eye, slightly pre-fixed with paraformaldehyde and stored at –80°C for 4 years. We tried three fixatives (pa­raformaldehyde [PFA], alcohol/acetic acid [AAA] and methanol) for post-fixation of eye sections. Results: We showed that post-fixation alters the labelling properties of vimentin expressed in the retina. In the sections with no post-fixation, vimentin positivity was observed in and around the nuclei in non-fibrillary form. In PFA post-fixed sections, the vimentin in the retina was not observed as fibrils. Positivity was observed in the nuclei and in perinuclear regions of the cells. In AAA post-fixed sections, positive labelling was observed around the nuclei as fibrils. In methanol post-fixed sections, labelling was observed around the nuclei as fibrils. Conclusions: We conclude that post-fixation with AAA is more convenient for immunofluorescent labelling of vimentin in the retina for slightly PFA pre-fixed and long-term stored retina. (Folia Morphol 2018; 77, 2: 246–252

Scalar mesons in radiative \phi\to K^0\bar{K}^0\gamma decay

We study the radiative $\phi\to K^0\bar{K}^0\gamma$ decay within a phenomenological framework by considering the contributions of the $f_{0}(980)$ and $a_{0}(980)$ scalar resonances. We calculate the branching ratio $B(\phi\to K^0\bar{K}^0\gamma)$ by employing the coupling constants $g_{f_0K^{+}K^{-}}$ and $g_{a_0K^{+}K^{-}}$ as determined by different experimental groups.Comment: 10 pages, 3 figure

Accelerated aging effects on color and translucency of flowable composites

OBJECTIVES: To evaluate the effect of accelerated aging on color and translucency parameter of composites. MATERIALS AND METHODS: Filtek Supreme Ultra Flowable, shades A1, A3, White, Tetric EvoFlow, shades A1, A3, Bleach, and Filtek Z250 shades A1, A3, B1 were evaluated. Color and translucency were recorded using a spectrophotometer after 24-hour storage (baseline) and after accelerated aging. The data were analyzed by analysis of variance. RESULTS: Fisher\u27s PLSD intervals for comparisons among products and shades were 0.4, 0.1, 0.3, and 0.4 for ΔL*, Δa*, Δb*, and ΔE*, respectively. The data showed significant ΔE* and ΔL* main effects for composite product and shades (p \u3c 0.001) and their interactions (p = 0.008 and p = 0.03), respectively. Tetric EvoFlow displayed the smallest aging-dependent color shift followed by Filtek Z250 and Filtek Supreme Ultra Flowable. Accelerated aging did not significantly affected the composites for translucency (p \u3e 0.05). CONCLUSION: The effects of aging on color of resin composites were composite and shade dependent. Translucency was not affected by accelerated aging. CLINICAL SIGNIFICANCE: The effects of aging on color of resin composites were composite and shade dependent

Pathogenicity of proteinase 3-anti-neutrophil cytoplasmic antibody in granulomatosis with polyangiitis: Implications as biomarker and future therapies

Granulomatosis with polyangiitis (GPA) is a rare but serious necrotizing auto-immune vasculitis. GPA is mostly associated with the presence of Anti-Neutrophil Cytoplasmic Antibody (ANCA) targeting proteinase 3 (PR3-ANCA), a serine protease contained in neutrophil granules but also exposed at the membrane. PR3-ANCAs have a proven fundamental role in GPA: they bind neutrophils allowing their auto-immune activation responsible for vasculitis lesions. PR3-ANCAs bind neutrophil surface on the one hand by their Fab binding PR3 and on the other by their Fc binding Fc gamma receptors. Despite current therapies, GPA is still a serious disease with an important mortality and a high risk of relapse. Furthermore, although PR3-ANCAs are a consistent biomarker for GPA diagnosis, relapse management currently based on their level is inconsistent. Indeed, PR3-ANCA level is not correlated with disease activity in 25% of patients suggesting that not all PR3-ANCAs are pathogenic. Therefore, the development of new biomarkers to evaluate disease activity and predict relapse and new therapies is necessary. Understanding factors influencing PR3-ANCA pathogenicity, i.e. their potential to induce auto-immune activation of neutrophils, offers interesting perspectives in order to improve GPA management. Most relevant factors influencing PR3-ANCA pathogenicity are involved in their interaction with neutrophils: level of PR3 autoantigen at neutrophil surface, epitope of PR3 recognized by PR3-ANCA, isotype and glycosylation of PR3-ANCA. We detailed in this review the advances in understanding these factors influencing PR3-ANCA pathogenicity in order to use them as biomarkers and develop new therapies in GPA as part of a personalized approach

Effects of Blade Discharge Angle, Blade Number and Splitter Blade Length on Deep Well Pump Performance

Impellers with splitter blades are used for pumps and compressors in the design of turbomachines. Design parameters such as the number of blades, blade discharge angle and impeller discharge diameter impact affect pump performance and energy consumption. In this study, the effect of the number of blades (z=5, 6, and 7), blade discharge angles (β2b=25, and β2b=35) and splitter blade lengths (40, 55, 70, and 85% of the main blade length) on Deep Well Pump (DWP) performance has been studied experimentally. In the experiments, pump casing, blade inlet angle, blade thickness, blade width and impeller inlet and discharge diameters have been kept fixed while other parameters such as the number of blades, blade discharge angles and splitter blade lengths have been allowed to vary. As a result of the experimental study, the highest efficiency of all the impellers for best efficiency point (b.e.p) has been obtained on the impeller with the number of blades z=6, blade discharge angle 2b=25 and 85% splitter blade addition compared to impellers without splitter blades

Human fascioliasis

ABSTRACTFasciola hepatica, a zoonotic liver fluke, can also cause disease in humans. Common symptoms are epigastric pain, upper abdominal pain and malaise. Fever and arthralgia are common in acute fascioliasis. Eosinophilia is the predominant laboratory finding, especially in patients with the acute form of the disease. Diagnosis and treatment is not easy, as physicians rarely encounter this disease, and effective drugs are not available in many countries. Human fascioliasis may be underestimated. Patients with eosinophilia and abdominal pain should be evaluated for F. hepatica infestation by parasitological, radiological and serological tests

Automorphism groups of some pure braid groups

We find finite presentations for the automorphism group of the Artin pure braid group and the automorphism group of the pure braid group associated to the full monomial group

Acute and delayed sulfur mustard toxicity; novel mechanisms and future studies

Sulfur mustard (SM), also known as mustard gas, has been the most widely used chemical weapon. The toxicity of SM as an incapacitating agent is of much greater importance than its ability to cause lethality. Acute toxicity of SM is related to reactive oxygen and nitrogen species, DNA damage, poly(ADP-ribose) polymerase activation and energy depletion within the affected cell. Therefore melatonin shows beneficial effects against acute SM toxicity in a variety of manner. It scavenges most of the oxygen- and nitrogen-based reactants, inhibits inducible nitric oxide synthase, repairs DNA damage and restores cellular energy depletion. The delayed toxicity of SM however, currently has no mechanistic explanation. We propose that epigenetic aberrations may be responsible for delayed detrimental effects of mustard poisoning. Epigenetic refers to the study of changes that influence the phenotype without causing alteration of the genotype. It involves changes in the properties of a cell that are inherited but do not involve a change in DNA sequence. It is now known that in addition to genetic mutations, epimutations can also involve in the pathogenesis of a variety of human diseases. Several actions of melatonin are now delineated by epigenetic actions including modulation of histone acetylation and DNA methylation. Future studies are warranted to clarify whether epigenetic mechanisms are involved in pathogenesis of delayed sulfur mustard toxicity and melatonin alleviates delayed toxicity of this warfare agent