Added mass energy recovery of octopus-inspired shape change

Dynamic shape change of the octopus mantle during fast jet escape manoeuvres results in added mass energy recovery to the energetic advantage of the octopus, giving escape thrust and speed additional to that due to jetting alone. We show through numerical simulations and experimental validation of overall wake behaviour, that the success of the energy recovery is highly dependent on shrinking speed and Reynolds number, with secondary dependence on shape considerations and shrinking amplitude. The added mass energy recovery ratio η[subscript ma], which measures momentum recovery in relation to the maximum momentum recovery possible in an ideal flow, increases with increasing the non-dimensional shrinking parameter σ[superscript ∗]=ȧ[subscript max]/U√(Re[subscript 0]), where ȧ[subscript max] is the maximum shrinking speed, U is the characteristic flow velocity and √(Re0) is the Reynolds number at the beginning of the shrinking motion. An estimated threshold σ[superscript ∗]≈10 determines whether or not enough energy is recovered to the body to produce net thrust. Since there is a region of high transition for 10100 added mass energy is recovered at diminishing returns, we propose a design criterion for shrinking bodies to be in the range of 50<σ[superscript ∗]<100, resulting in 61–82 % energy recovery

ADSORPTION OF PHENOLS FROM OLIVE OIL MILL WASTEWATER AS WELL AS N AND P FROM A SIMULATED CITY WASTEWATER LIQUID ON ACTIVATED GREEK LIGNITES

The results show that surface area of activated coal samples increased substantially and in some more than the commercial one. The increase in surface area was higher the higher the carbon content and the lower the ash content. The adsorption capacity of phenols and the decrease of COD (Chemical Oxygen Demand) in olive oil mil wastewater disposals were measured in selected samples as well as the decrease of COD and the adsorption of nitrogen and phosphorus from a solution which simulates city waste disposals were measured in 14 selected Greek lignites and 1 commercially available activated lignite sample (HOK). The maximum recorded adsorption of phenol was 30.6 mg/g of activated lignite while the commercial one (HOK) adsorbed 16 mg/g of activated lignite. The COD reduction was 1262 mg of COD/g of activated lignite while in the commercial one the reduction was 439 mg of COD/g of activated lignite. The maximum adsorption of N and P from the simulated city waste liquid was 6.41 mg/g of activated lignite and 2.52 mg/g of activated lignite, respectively. while the commercial one (HOK) adsorbed 2.84 mg/g and 2.42 mg/g, respectively. Finally, the COD reduction was 50.28 mg/g of activatedlignite and 34.92 mg/g for the commercially one (HOK). The results show that Greek activated lignites can be used successfully for cleaning industrial and city wastes. These findings open the door for the economic exploitation of small to medium size lignite deposits in Greece, which are widespread in Greece

Shape of retracting foils that model morphing bodies controls shed energy and wake structure

The flow mechanisms of shape-changing moving bodies are investigated through the simple model of a foil that is rapidly retracted over a spanwise distance as it is towed at constant angle of attack. It is shown experimentally and through simulation that by altering the shape of the tip of the retracting foil, different shape-changing conditions may be reproduced, corresponding to: (i) a vanishing body, (ii) a deflating body and (iii) a melting body. A sharp-edge, ‘vanishing-like’ foil manifests strong energy release to the fluid; however, it is accompanied by an additional release of energy, resulting in the formation of a strong ring vortex at the sharp tip edges of the foil during the retracting motion. This additional energy release introduces complex and quickly evolving vortex structures. By contrast, a streamlined, ‘shrinking-like’ foil avoids generating the ring vortex, leaving a structurally simpler wake. The ‘shrinking’ foil also recovers a large part of the initial energy from the fluid, resulting in much weaker wake structures. Finally, a sharp edged but hollow, ‘melting-like’ foil provides an energetic wake while avoiding the generation of a vortex ring. As a result, a melting-like body forms a simple and highly energetic and stable wake, that entrains all of the original added mass fluid energy. The three conditions studied correspond to different modes of flow control employed by aquatic animals and birds, and encountered in disappearing bodies, such as rising bubbles undergoing phase change to fluid

CD14+ CD15- HLA-DR- myeloid-derived suppressor cells impair antimicrobial responses in patients with acute-on-chronic liver failure.

OBJECTIVE: Immune paresis in patients with acute-on-chronic liver failure (ACLF) accounts for infection susceptibility and increased mortality. Immunosuppressive mononuclear CD14+HLA-DR- myeloid-derived suppressor cells (M-MDSCs) have recently been identified to quell antimicrobial responses in immune-mediated diseases. We sought to delineate the function and derivation of M-MDSC in patients with ACLF, and explore potential targets to augment antimicrobial responses. DESIGN: Patients with ACLF (n=41) were compared with healthy subjects (n=25) and patients with cirrhosis (n=22) or acute liver failure (n=30). CD14+CD15-CD11b+HLA-DR- cells were identified as per definition of M-MDSC and detailed immunophenotypic analyses were performed. Suppression of T cell activation was assessed by mixed lymphocyte reaction. Assessment of innate immune function included cytokine expression in response to Toll-like receptor (TLR-2, TLR-4 and TLR-9) stimulation and phagocytosis assays using flow cytometry and live cell imaging-based techniques. RESULTS: Circulating CD14+CD15-CD11b+HLA-DR- M-MDSCs were markedly expanded in patients with ACLF (55% of CD14+ cells). M-MDSC displayed immunosuppressive properties, significantly decreasing T cell proliferation (p=0.01), producing less tumour necrosis factor-alpha/interleukin-6 in response to TLR stimulation (all p<0.01), and reduced bacterial uptake of Escherichia coli (p<0.001). Persistently low expression of HLA-DR during disease evolution was linked to secondary infection and 28-day mortality. Recurrent TLR-2 and TLR-4 stimulation expanded M-MDSC in vitro. By contrast, TLR-3 agonism reconstituted HLA-DR expression and innate immune function ex vivo. CONCLUSION: Immunosuppressive CD14+HLA-DR- M-MDSCs are expanded in patients with ACLF. They were depicted by suppressing T cell function, attenuated antimicrobial innate immune responses, linked to secondary infection, disease severity and prognosis. TLR-3 agonism reversed M-MDSC expansion and innate immune function and merits further evaluation as potential immunotherapeutic agent

TAM receptors in the pathophysiology of liver disease

TAM receptors (Tyro3, Axl and MerTK) are a family of tyrosine kinase receptors that are expressed in a variety of cell populations, including liver parenchymal and non-parenchymal cells. These receptors are vital for immune homeostasis, as they regulate the innate immune response by suppressing inflammation via toll-like receptor inhibition and by promoting tissue resolution through efferocytosis. However, there is increasing evidence indicating that aberrant TAM receptor signaling may play a role in pathophysiological processes in the context of liver disease. This review will explore the roles of TAM receptors and their ligands in liver homeostasis as well as a variety of disease settings, including acute liver injury, steatosis, fibrosis, cirrhosis-associated immune dysfunction and hepatocellular carcinoma. A better understanding of our current knowledge of TAM receptors in liver disease may identify new opportunities for disease monitoring as well as novel therapeutic targets. Nonetheless, this review also aims to highlight areas where further research on TAM receptor biology in liver disease is required

An Improved Shortcut Design Method of Divided Wall Columns Exemplified by a Liquefied Petroleum Gas Process

Designing a sustainable and economical distillation system is a big global challenge in the industrial chemical field. To address this issue, one of most promising solutions is the so-called dividing wall columns addressed in this work, which not only can cut energy cost but also use limited installation space. An improved shortcut design approach is developed in this work to provide accurate models for each section of dividing wall columns; meanwhile Underwood’s and Gilliland’s equations are employed to determine minimum reflux ratio and total number of stages in different column sections in terms of corresponding design specifications and operating conditions. This proposed approach has been applied to separations of mixtures of hydrocarbons and alcohol with different values on the ease of separation index. To test its effectiveness, the preliminary design parameters obtained through the improved proposed shortcut method are further validated by a rigorous simulation in Aspen HYSYS. Furthermore, the results indicate that this method could provide much more accuracy of average interconnecting stream composition of the prefractionator and main column than those of other methods. In practice, this method has been applied to a case of liquefied petroleum gas (LPG) separation with three targeted products in an industrial liquefied petroleum gas plant. The applications and efficiency of the shortcut method in this study lay a theoretical foundation for designing the separation of ideal mixtures involving dividing wall columns

Logarithmic spin, logarithmic rate and material frame-indifferent generalized plasticity

In this work we present a new rate type formulation of large deformation generalized plasticity which is based on the consistent use of the logarithmic rate concept. For this purpose, the basic constitutive equations are initially established in a local rotationally neutralized configuration which is defined by the logarithmic spin. These are then rephrased in their spatial form, by employing some standard concepts from the tensor analysis on manifolds. Such an approach, besides being compatible with the notion of (hyper)elasticity, offers three basic advantages, namely:(i) The principle of material frame-indifference is trivially satisfied ; (ii) The structure of the infinitesimal theory remains essentially unaltered ; (iii) The formulation does not preclude anisotropic response. A general integration scheme for the computational implementation of generalized plasticity models which are based on the logarithmic rate is also discussed. The performance of the scheme is tested by two representative numerical examples

The acute effect of the antioxidant drug “U-74389G” on mean platelet volume levels during hypoxia reoxygenation injury in rats

AbstractBackgroundThis experimental study examined the effect of the antioxidant drug “U-74389G”, on a rat model and particularly in a hypoxia – reoxygenation protocol. The effects of that molecule were studied hematologically using blood mean platelets volume (MPV) levels.Methods40 rats of mean weight 231.875g were used in the study. MPV levels were measured at 60min of reoxygenation (groups A and C) and at 120min of reoxygenation (groups B and D). The drug U-74389G was administered only in groups C and D.ResultsU-74389G administration kept significantly increased the predicted MPV levels by 12.77±3.07% (p=0.0001). Reoxygenation time non-significantly decreased the predicted MPV levels by 2.55±3.71% (p=0.4103). However, U-74389G administration and reoxygenation time together kept significantly increased the predicted MPV levels by 7.09±1.91% (p=0.0005).ConclusionsU-74389G administration whether it interacted or not with reoxygenation time kept significantly increased the predicted MPV levels. This finding has great clinical interest in blood clotting and coagulation pathophysiology

An Image Analysis System for the Assessment of Retinal Microcirculation in Hypertension and Its Clinical Evaluation

Abstract — A system for the assessment of hypertension through the measurement of retinal vessels in fundoscopy images, is presented. The proposed approach employs multiple image analysis methods, in an integrated system that is used in clinical practice. Automating the measurement process enables the conduct of a clinical study that, for the first time, shows the correlation between macrovascular and microvascular al-terations, based on numerous measurements acquired by this system. Experience and perspectives gained from clinical usage and evaluation are reported. I

The effect of the antioxidant drug “U-74389G†on testosterone levels during ischemia reperfusion injury in rats

Background: This experimental study examined the effect of the antioxidant drug “U-74389Gâ€, on a rat model and particularly in an adrenal ischemia - reperfusion protocol. The effects of that molecule were studied biochemically using blood mean testosterone (T) levels.Materials and methods: 40 rats of mean weight 231.875 g were used in the study. Testosterone levels were measured at 60 min of reperfusion (groups A and C) and at 120 min of reperfusion (groups B and D), A and B without but C and D with U-74389G administration.Results: U-74389G administration significantly increased the T levels by 52.17%+28.69% (p=0.0451). Reperfusion time significantly decreased the T levels by 85.62%+26.33% (P= 0.0019). However, U-74389G administration and reperfusion time together produced a non-significant combined effect in increasing the T levels by 11.18%+17.97% (p= 0.5245).Conclusions: U-74389G administration interacted or not with reperfusion time increased short – term the testosterone levels.        Â