Propagation and deposition of stony debris flows at channel confluences

The fluid dynamics of stony debris flows generated in two small tributaries adjacent to each other and flowing into a main receiving channel was analyzed experimentally at a laboratory scale. The analysis on the propagation along the tributaries and deposition in the main channel provide information about sediment-water mobility, dangerous damming, and potential hazard. Debris flows were generated by releasing a preset water discharge over an erodible layer of saturated gravels material. As a consequence, the debris flow sediment concentration varied accordingly to the entrainment rate which, in turn, was strongly controlled by the tributary slope. The data collected by acoustic level sensors, pore fluid pressure transducers, and a load cell were used to characterize the evolution of bulk density and solid concentration of the sediment-water mixture. These two parameters were relevant to assess the stony debris flow mobility which contributes to determine the shape of sediment deposits in the main channel. The detailed bed topography surveys carried out in the main channel at the end of each experiment provided information on the morphology of these deposits and on the interplay of adjacent confluences. The influences of conflu- ence angle, tributary slopes, and triggering conditions have been investigated, for a total of 18 different configurations. Within the investigated range of parameters, the slope angle was the parameter that mainly influences the stony debris flow mobility while, for adjacent confluences, the degree of obstruction within the receiving channel was strongly influenced by the triggering scenario

Coarse-grained debris flow dynamics on erodible beds.

A systematic set of flume experiments is used to investigate the features of velocity profiles within the body of coarse-grained debris flows and the dependence of the transport sediment concentration on the relevant parameters (runoff discharge, bed slope, grain size and form). The flows are generated in a 10 m long laboratory flume, initially filled with a layer consisting of loose debris. After saturation, a prescribed water discharge is suddenly supplied over the granular the runoff triggers a debris flow wave that reaches nearly steady conditions. Three types of material have been used in the tests: gravel with mean grain size of 3 and 5 mm, and 3 mm glass spheres. Measured parameters included: triggering water discharge, volumetric sediment discharges, sediment concentration, flow depth and velocity profiles. The dynamic similarity with full-sized debris flows is discussed on the basis of the relevant dimensionless parameters. Concentration data highlight the dependence on the slope angle and the importance of the quasi-static friction angle. The effects of flow rheology on the shape of velocity profiles are analyzed with attention to the role of different stress generating mechanisms. A remarkable collapse of the dimensionless profiles is obtained by scaling the debris flow velocity with the runoff velocity, and a power law characterization is proposed following a heuristic approach. The shape of the profiles suggests a smooth transition between the different rheological regimes (collisional and frictional) that establish in the upper and lower regions of the flow, and is compatible with the presence of multiple length scales

El taller de escritura académica para estudiantes de intercambio

El aumento en la cantidad de estudiantes universitarios extranjeros no hispanohablantes que llegan a nuestro país a través de un programa de intercambio nos enfrenta con el tema del desempeño académico en una lengua extranjera. La mayoría de ellos tiene un nivel intermedio o avanzado de español y, por otra parte, ha adquirido habilidades académicas en su lengua materna. Sin embargo, su desempeño en las universidades locales revela que muchos de ellos tienen dificultades para la comprensión de textos complejos en español; de la misma manera, sus producciones escritas muestran inadecuaciones con respecto a las expectativas de un lector hispanohablante experto. Por estas razones, les resulta difícil cumplir con los diferentes requerimientos del medio universitario. Como profesores de español de estos estudiantes, nos vemos enfrentados al desafío de ofrecerles herramientas para que puedan mejorar su desempeño y aprovechar al máximo su experiencia de inmersión. A partir del análisis de un corpus de textos producidos por estudiantes universitarios estadounidenses durante sus estudios en Buenos Aires, y tomando en cuenta desarrollos teóricos de la lingüística aplicada y de la sociolingüística, se discutirán las posibles fuentes de estas dificultades y se propondrán contenidos y actividades para trabajar en un taller de escritura académica destinado al mejoramiento de las habilidades en esta área.Facultad de Humanidades y Ciencias de la Educació

Malignant melanoma with liver and spleen metastases: case report

CONTEXT: The diagnosis of primary melanoma is easily confirmed after histological analysis of the lesion, whereas it is rarely diagnosed when the patient even has distant metastases. DESIGN: Case report CASE REPORT: Malignant melanoma is responsible for about 1% of all deaths caused by cancer in the USA and only 3% of all malig-nant skin diseases. Malignant melanoma is a rare disease, although it corresponds to 65% of all deaths caused by skin cancer. The liver and spleen are rarely the first sites of melanoma metastases. This paper reports on the clinical picture of a patient with fatal malignant melanoma and hepatic and spleen metastases. As this was an un-usual presentation, the melanoma diagnosis could only be made after pathological analysis of the skin and hepatic lesions.CONTEXTO: O melanoma maligno é responsável por aproximadamente 1% de todas as mortes causadas por câncer nos EUA e apenas 3% de todas as doenças malignas cutâneas. Embora considerada uma patologia rara, representa 65% de todos os óbitos por câncer de pele. O fígado e o baço raramente são os primeiros sítios de metástases de melanoma. TIPO DE ESTUDO: Relato de caso. RELATO DE CASO: Este artigo relata o quadro de um paciente portador de melanoma maligno evoluindo para óbito com metástases hepática e esplênica. Por ser uma apresentação atípica da doença, o diagnóstico definitivo ocorreu somente após a análise histopatológica das lesões de pele e do fígado.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Department of PathologyUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Gastroenterology DivisionUNIFESP, EPM, Department of PathologyUNIFESP, EPM, Gastroenterology DivisionSciEL

EFFECT OF LIVING MULCH ON PEST/BENEFICIAL INTERACTION

The aim of this study was to evaluate the effect of cover crops on pest/beneficial dynamics and to test the potential of living mulch on enhancing biological control against insect pests. The research, carried out in the frame of the InterVeg (Core Organic II) project, involved four European countries: Germany, Slovenia, Denmark and Italy. Three crops were tested: cauliflower, leek and artichoke. The preliminary results obtained in Italy on cauliflower, indicated that the living mulch did not affect the infestation of the cabbage butterfly, Pieris brassicae, showing no detrimental effect of this technique on pest dynamics. A very high level of parasitization against cabbage butterfly was detected either in the living mulch crop (88%) and in the sole one (63%). Living mulch showed to increase the spider and rove beetle activity density, while the carabid activity density was slightly higher in the sole crop

EFFECT OF LIVING MULCH ON PEST/BENEFICIAL INTERACTION

The aim of this study was to evaluate the effect of cover crops on pest/beneficial dynamics and to test the potential of living mulch on enhancing biological control against insect pests. The research, carried out in the frame of the InterVeg (Core Organic II) project, involved four European countries: Germany, Slovenia, Denmark and Italy. Three crops were tested: cauliflower, leek and artichoke. The preliminary results obtained in Italy on cauliflower, indicated that the living mulch did not affect the infestation of the cabbage butterfly, Pieris brassicae, showing no detrimental effect of this technique on pest dynamics. A very high level of parasitization against cabbage butterfly was detected either in the living mulch crop (88%) and in the sole one (63%). Living mulch showed to increase the spider and rove beetle activity density, while the carabid activity density was slightly higher in the sole crop

Term amniotic membrane is a high throughput source for multipotent mesenchymal stem cells with the ability to differentiate into endothelial cells in vitro

BACKGROUND: Term Amniotic membrane (AM) is a very attractive source of Mesenchymal Stem Cells (MSCs) due to the fact that this fetal tissue is usually discarded without ethical conflicts, leading to high efficiency in MSC recovery with no intrusive procedures. Here we confirmed that term AM, as previously reported in the literature, is an abundant source of hMSCs; in particular we further investigated the AM differentiation potential by assessing whether these cells may also be committed to the angiogenic fate. In agreement with the recommendation of the International Society for Cellular Therapy, the mesenchymal cells herein investigated were named Amniotic Membrane-human Mesenchymal Stromal Cells (AM-hMSC). RESULTS: The recovery of hMSCs and their in vitro expansion potential were greater in amniotic membrane than in bone marrow stroma. At flow cytometry analysis AM-hMSCs showed an immunophenotypical profile, i.e., positive for CD105, CD73, CD29, CD44, CD166 and negative for CD14, CD34, CD45, consistent with that reported for bone marrow-derived MSCs. In addition, amniotic membrane-isolated cells underwent in vitro osteogenic (von Kossa stain), adipogenic (Oil Red-O stain), chondrogenic (collagen type II immunohistochemichal detection) and myogenic (RT-PCR MyoD and Myogenin expression as well as desmin immunohistochemical detection) differentiation. In angiogenic experiments, a spontaneous differentiation into endothelial cells was detected by in vitro matrigel assay and this behaviour has been enhanced through Vascular Endothelial Growth Factor (VEGF) induction. According to these findings, VEGF receptor 1 and 2 (FLT-1 and KDR) were basally expressed in AM-hMSCs and the expression of endothelial-specific markers like FLT-1 KDR, ICAM-1 increased after exposure to VEGF together with the occurrence of CD34 and von Willebrand Factor positive cells. CONCLUSION: The current study suggests that AM-hMSCs may emerge as a remarkable tool for the cell therapy of multiple diseased tissues. AM-hMSCs may potentially assist both bone and cartilage repair, nevertheless, due to their angiogenic potential, they may also pave the way for novel approaches in the development of tissue-engineered vascular grafts which are useful when vascularization of ischemic tissues is required

Angiogenic potential of human dental pulp stromal (stem) cells.

Dental pulp is a heterogeneous microenviroment where unipotent progenitor and pluripotent mesenchymal stem cells cohabit. In this study we investigated whether human Dental Pulp Stromal (Stem) Cells (DP-SCs) committed to the angiogenic fate. DP-SCs showed the specific mesenchymal immunophenotypical profile positive for CD29, CD44, CD73, CD105, CD166 and negative for CD14, CD34, CD45, in accordance with that reported for bone marrow-derived SCs. The Oct-4 expression in DP-SCs, evaluated through RT-PCR analysis, increased in relation with the number of the passages in cell culture and decreased after angiogenic induction. In agreement with their multipotency, DP-SCs differentiated toward osteogenic and adipogenic commitments. In angiogenic experiments, differentiation of DP-SCs, through Vascular Endothelial Growth Factor (VEGF) induction, was evaluated by in vitro matrigel assay and by cytometric analysis. Accordingly, endothelial-specific markers like Flt-1 and KDR were basally expressed and they increased after exposure to VEGF together with the occurrence of ICAM-1 and von Willebrand Factor positive cells. In addition, VEGF-induced DP-SCs maintained endothelial cell-like features when cultured in a 3-D fibrin mesh, displaying focal organization into capillary-like structures. The DP-SC angiogenic potential may prove a remarkable tool for novel approaches to developing tissue-engineered vascular grafts which are useful when vascularization of ischemic tissues is required

Left ventricular chamber dilation and filling pressure may help to categorise patients with type 2 diabetes

Type 2 diabetes may alter cardiac structure and function. Many patients with type 2 diabetes have diastolic dysfunction with preserved ejection fraction (EF). Recently, this latter measure was criticised. Thus, this research looked at the impact of left ventricular end-diastolic volume and E/e' ratio variations in patients with type 2 diabetes and preserved EF with the aim to recognise different clinical phenotypes

Gastrointestinal presentation of kawasaki disease: A red flag for severe disease?

Background Kawasaki disease (KD) is a febrile systemic vasculitis of unknown etiology and the main cause of acquired heart disease among children in the developed world. To date, abdominal involvement at presentation is not recognized as a risk factor for a more severe form of the disease. Objective To evaluate whether presenting abdominal manifestations identify a group at major risk for Intravenous immunoglobulin (IVIG)-resistance and coronary lesions. Methods Retrospective study of KD patients diagnosed between 2000 and 2015 in 13 pediatric units in Italy. Patients were divided into 2 groups according to the presence or absence of abdominal manifestations at onset. We compared their demographic and clinical data, IVIG-responsiveness, coronary ectasia/aneurysms, laboratory findings from the acute and subacute phases. Results 302 patients (181 boys) were enrolled: 106 patients with, and 196 patients without presenting abdominal features. Seasonality was different between the groups (p = 0.034). Patients with abdominal manifestations were younger (p = 0.006) and more frequently underwent delayed treatment (p = 0.014). In the acute phase, patients with abdominal presentation had higher platelet counts (PLT) (p = 0.042) and lower albuminemia (p = 0.009), while, in the subacute phase, they had higher white blood cell counts (WBC) and PLT (p = 0.002 and p < 0.005, respectively) and lower red blood cell counts (RBC) and hemoglobin (Hb) (p = 0.031 and p 0.009). Moreover, the above mentioned group was more likely to be IVIG-resistant (p < 0.005) and have coronary aneurysms (p = 0.007). In the multivariate analysis, presenting abdominal manifestations, age younger than 6 months, IVIG- resistance, delayed treatment and albumin concentration in the acute phase were independent risk factors for coronary aneurysms (respectively p<0.005, <0.005, = 0.005 and 0.009). Conclusions This is the first multicenter report demonstrating that presenting gastrointestinal features in KD identify patients at higher risk for IVIG-resistance and for the development of coronary aneurysms in a predominantly Caucasian population