Sensitivity analysis of bridge pier scour depth predictive formulae

Sensitivity analysis is an approach to recognising the behaviour of models and relative importance of causative factors. In this paper, behaviours of six pier scour depth empirical formulae are evaluated on the basis of an analytical method. The sensitivity of predicted scour depth is analysed with respect to the following independent parameters: approach flow depth, riverbed slope and median sediment size. Also their combined influence is studied examining the relative importance of each parameter with respect to the total variation of the maximum scour depth. Results show that: (1) sensitivity significantly depends on flow intensity for most of the selected formulae, whereas for the others it is a constant value or depends on other influencing parameters; (2) different formulae demonstrate various level of sensitivity to the input variables, so that, for a certain error in the input variables, the error in the results may vary consistently; (3) some formulae are very sensitive to the input parameters under some conditions, hence an error in an input variable may be amplified in the output results; and (4) most of the formulae are more sensitive to the variations of the influencing parameters in clear-water than in live-bed conditions

Anisotropy in the Turbulent Flow through Random and Emergent Rigid Vegetation on Rough Beds

In this study, we explore for the first time the turbulence anisotropy of flows through random and emergent rigid vegetation on rough beds, using the anisotropy invariant maps (AIMs). We present the results of an experimental campaign, based on Acoustic Doppler Velocimeter (ADV) measures, varying the bed sediment size (coarse sand, fine gravel, and coarse gravel), under the same hydraulic conditions. The evolution of the stress ellipsoid formed by the Reynolds stresses is discussed, together with the analysis of the anisotropic invariant function. We demonstrate that vegetation distribution is of paramount importance in the turbulence anisotropy evolution along the water depth. While in the case of a regular pattern the bed roughness is the key parameter in determining the shape of the stress ellipsoid in the near-bed region, in a random vegetation distribution this assumption is no longer valid. However, by increasing the bed roughness in such kind of arrangement, its effect on the turbulence anisotropy are visible in specific areas around the vegetation stem. This is confirmed by the analysis of the anisotropic invariant function calculated for different sections close to the stem itself

Turbulence in mobile-bed streams

This study is devoted to quantify the near-bed turbulence parameters in mobile-bed flows with bed-load transport. A reduction in near-bed velocity fluctuations due to the decrease of flow velocity relative to particle velocity of the transporting particles results in an excessive near-bed damping in Reynolds shear stress (RSS) distributions. The bed particles are associated with the momentum provided from the flow to maintain their motion overcoming the bed resistance. It leads to a reduction in RSS magnitude over the entire flow depth. In the logarithmic law, the von Kármán coefficient decreases in presence of bed-load transport. The turbulent kinetic energy budget reveals that for the bed-load transport, the pressure energy diffusion rate near the bed changes sharply to a negative magnitude, implying a gain in turbulence production. According to the quadrant analysis, sweep events in mobile-bed flows are the principal mechanism of bed-load transport. The universal probability density functions for turbulence parameters given by Bose and Dey have been successfully applied in mobile-bed flows

Experimental and Numerical Study of Free-Surface Flows in a Corrugated Pipe

A new discharge computational model is proposed on the basis of the integration of the velocity profile across the flow cross-section in an internally corrugated pipe flowing partially full. The model takes into account the velocity profiles in the pressurised pipe to predict the flow rate under free-surface flow conditions. The model was evaluated through new laboratory experiments as well as a literature datasets. The results show that flow depth and pipe slope may affect the model accuracy; nevertheless, a prediction error smaller than 20% is expected from the model. Experimental results reveal the influence of the pipe slope and flow depth on the friction factor and the stage-discharge curves: the friction factor may increase with pipe slope, while it reduces as flow depth increases. Hence, a notable change of pipe slope may lead to the variation of the stage-discharge curve. A part of this study deals with numerical simulation of the velocity profiles and the stage-discharge curves. Using the Reynolds-Averaged Navier-Stokes (RANS) equations, numerical solutions were obtained to simulate four experimental tests, obtaining enough accurate results as to velocity profiles and water depths. The results of the simulated flow velocity were used to estimate the flow discharge, confirming the potential of numerical techniques for the prediction of stage-discharge curves

Inflammatory Cells in Diffuse Large B Cell Lymphoma

Diffuse large B cell lymphoma (DLBCL), known as the most common non-Hodgkin lymphoma (NHL) subtype, is characterized by high clinical and biological heterogeneity. The tumor microenvironment (TME), in which the tumor cells reside, is crucial in the regulation of tumor initiation, progression, and metastasis, but it also has profound effects on therapeutic efficacy. The role of immune cells during DLBCL development is complex and involves reciprocal interactions between tumor cells, adaptive and innate immune cells, their soluble mediators and structural components present in the tumor microenvironment. Different immune cells are recruited into the tumor microenvironment and exert distinct effects on tumor progression and therapeutic outcomes. In this review, we focused on the role of macrophages, Neutrophils, T cells, natural killer cells and dendritic cells in the DLBCL microenvironment and their implication as target for DLBCL treatment. These new therapies, carried out by the induction of adaptive immunity through vaccination or passive of immunologic effectors delivery, enhance the ability of the immune system to react against the tumor antigens inducing the destruction of tumor cells

Cryopreservation protocol for human biliary tree stem/progenitors, hepatic and pancreatic precursors

Human biliary tree stem/progenitor cells (hBTSCs) are being used for cell therapies of patients with liver cirrhosis. A cryopreservation method was established to optimize sourcing of hBTSCs for these clinical programs and that comprises serum-free Kubota's Medium (KM) supplemented with 10% dimethyl sulfoxide (DMSO), 15% human serum albumin (HSA) and 0.1% hyaluronans. Cryopreserved versus freshly isolated hBTSCs were similar in vitro with respect to self-replication, stemness traits, and multipotency. They were able to differentiate to functional hepatocytes,cholangiocytes or pancreatic islets, yielding similar levels of secretion of albumin or of glucose-inducible levels of insulin. Cryopreserved versus freshly isolated hBTSCs were equally able to engraft into immunocompromised mice yielding cells with human-specific gene expression and human albumin levels in murine serum that were higher for cryopreserved than for freshly isolated hBTSCs. The successful cryopreservation of hBTSCs facilitates establishment of hBTSCs cell banking offering logistical advantages for clinical programs for treatment of liver diseases

Relationship between eroded volume and main scour hole dimensions near quay walls caused by internal counter-rotating twin-propellers

The present study aims at computing and analysing the eroded sediment volumes induced by twin-propeller jets near a vertical quay wall from the main geometric characteristics of the scour hole. Two different scouring mechanisms govern the scouring process: i) the down-flow due to the interaction between the propellers jet and the wall, and ii) the direct impact of the propellers jet flow on the seabed. For this reason, the whole study area is divided into two subzones: 1) ’near the wall’ field; 2) ’far from the wall’ field. Both forward and backward rotation of the propellers during manoeuvring are analysed. The results show that, for the two manoeuvring states, the relationship between the eroded volume and the geometric characteristics of the scour hole in the near-wall subzone does not change, meaning that the backward rotation does not affect the morphology of the scour hole near the wall. Moreover, the eroded volume can be determined as a function of the maximum depth near the wall and, with higher accuracy, as a product of the three main geometric characteristics of the scour hole at any time-stage during the scour hole developmentPostprint (published version

Infiltración granulomatosa difusa del sistema digestivo compatible con infección por <i>Mycobacterium</i> spp. en Schnauzer miniatura

Las micobacteriosis son poco frecuentes en los caninos. Sin embargo, los Schnauzer miniatura se vuelven más susceptibles a ellas, ya que pueden ser inmunodeficientes debido a la presencia en homocigosis recesiva del gen CARD9 defectuoso. En estos individuos la infección se caracteriza por infiltración granulomatosa difusa del sistema gastrointestinal, lo que ocasiona vómitos, diarrea, pérdida de peso y linfadenopatia generalizada. El cuadro puede confundirse con enfermedades gastrointestinales neoplásicas, obstructivas, inflamatorias y parasitarias. El diagnóstico definitivo requiere de cultivo prolongado, el cual resulta a veces dificultoso, y de técnicas moleculares. Aún no existe antibioticoterapia eficaz y su uso se desaconseja dada la dificultad para implementarla sobre la base de pruebas de resistencia. Esto se suma al riesgo zoonótico para las personas inmunodeprimidas. El objetivo de este trabajo es describir un cuadro compatible con micobacteriosis en un Schnauzer miniatura joven desarrollado a posteriori de una situación estresante.Trabajo publicado en Cagliada, Maria del Pilar Lilia y Galosi, Cecilia Mónica (comps.). I Congreso de Microbiología Veterinaria. Libro de resúmenes. La Plata: Facultad de Ciencias Veterinarias, 2021.Facultad de Ciencias Veterinaria

Cytokine storm and histopathological findings in 60 cases of COVID-19-related death: from viral load research to immunohistochemical quantification of major players IL-1\u3b2, IL-6, IL-15 and TNF-\u3b1

This study involves the histological analysis of samples taken during autopsies in cases of COVID-19 related death to evaluate the inflammatory cytokine response and the tissue localization of the virus in various organs. In all the selected cases, SARS-CoV-2 RT-PCR on swabs collected from the upper (nasopharynx and oropharynx) and/or the lower respiratory (trachea and primary bronchi) tracts were positive. Tissue localization of SARS-CoV-2 was detected using antibodies against the nucleoprotein and the spike protein. Overall, we tested the hypothesis that the overexpression of proinflammatory cytokines plays an important role in the development of COVID-19-associated pneumonia by estimating the expression of multiple cytokines (IL-1\u3b2, IL-6, IL-10, IL-15, TNF-\u3b1, and MCP-1), inflammatory cells (CD4, CD8, CD20, and CD45), and fibrinogen. Immunohistochemical staining showed that endothelial cells expressed IL-1\u3b2 in lung samples obtained from the COVID-19 group (p\u2009&lt;\u20090.001). Similarly, alveolar capillary endothelial cells showed strong and diffuse immunoreactivity for IL-6 and IL-15 in the COVID-19 group (p\u2009&lt;\u20090.001). TNF-\u3b1 showed a higher immunoreactivity in the COVID-19 group than in the control group (p\u2009&lt;\u20090.001). CD8\u2009+\u2009T cells where more numerous in the lung samples obtained from the COVID-19 group (p\u2009&lt;\u20090.001). Current evidence suggests that a cytokine storm is the major cause of acute respiratory distress syndrome (ARDS) and multiple organ failure and is consistently linked with fatal outcomes

modelling and simulation for major incidents

In recent years, there has been a rise in Major Incidents with big impact on the citizens health and the society. Without the possibility of conducting live experiments when it comes to physical and/or toxic trauma, only an accurate in silico reconstruction allows us to identify organizational solutions with the best possible chance of success, in correlation with the limitations on available resources (e.g. medical team, first responders, treatments, transports, and hospitals availability) and with the variability of the characteristic of event (e.g. type of incident, severity of the event and type of lesions). Utilizing modelling and simulation techniques, a simplified mathematical model of physiological evolution for patients involved in physical and toxic trauma incident scenarios has been developed and implemented. The model formalizes the dynamics, operating standards and practices of medical response and the main emergency service in the chain of emergency management during a Major Incident