Search results for "Circulation"
showing 10 items of 1137 documents
Water absorption and hydrothermal ageing of epoxy adhesives reinforced with amino-functionalized graphene oxide nanoparticles
2021
Abstract The study is focused on quantitative characterization of water absorption and hydrothermal ageing effects in a room-temperature amine cured epoxy adhesive widely used in automotive, aerospace, construction, and marine industries. Amino-functionalized graphene oxide (mGO) nanoparticles were incorporated into the epoxy (up to 1.72 wt.%) enabled cross-linking reactions and providing high interfacial adhesion, superior reinforcement efficiency and enhanced resistance to hydrothermal ageing of nanocomposites. Anomalous water absorption accompanied by progressive weight loss of samples (down to 7%) is fitted by two-stage models considering additive and coupled contribution from water dif…
Geochemistry of REE, Zr and HF in a wide range of pH and water composition: The Nevado del Ruiz volcano hydrothermal system (Colombia)
2015
International audience; The geochemical behaviour of Rare Earth Elements, Zr and Hf was investigated in the thermal waters of Nevado del Ruiz volcano system. A wide range of pH, between 1.0 and 8.8, characterizes these fluids. The acidic waters are sulphate dominated with different Cl/SO4 ratios. The important role of the pH and the ionic complexes for the distribution of REE, Zr and Hf in the aqueous phase was evidenced. The pH rules the precipitation of authigenic Fe and Al oxyhydroxides producing changes in REE, Zr, Hf amounts and strong anomalies of Cerium. The precipitation of alunite and jarosite removes LREE from the solution, changing the REE distribution in acidic waters.Y–Ho and Z…
Acoustic doppler velocity profiler for velocity and turbulence measurements in a large amplitude meandering flume
2008
Flow over deformed bed of a meandering laboratory channel is experimentally investigated. The velocity components have been obtained using an Ultrasonic Doppler Profiler (DOP2000) that measures the instantaneous flow velocity profile along the probe direction. In this work, some results obtained in peculiar sections along the channel are reported. A refined mesh of the measurement points has been used for each considered cross-section. The analysis of the collected data essentially confirms that when the aspect ratio is small the secondary circulation assumes great importance and, in accordance with previous findings, a second counter-rotating secondary circulation cell appears near the fre…
3D microvascular architecture of pre-cancerous lesions and invasive carcinomas of the colon.
2001
Despite the significance of tumour neoangiogenesis and the extensive knowledge on the molecular basis of blood vessel formation currently no quantitative data exist on the 3D microvascular architecture in human primary tumours and their precursor lesions. This prompted us to examine the 3D vascular network of normal colon mucosa, adenomas and invasive carcinomas by means of quantitative microvascular corrosion casting. Fresh hemicolectomy specimens from 20 patients undergoing cancer or polyposis coli surgery were used for corrosion casting, factor VIII and VEGF immunostaining. In addition, immunostaining was done on colorectal tissue from 33 patients with metastatic and non-metastatic carci…
Pharmacological Interventions on Asymmetric Dimethylarginine, a Clinical Marker of Vascular Disease
2011
The aim of this paper is to review the latest data on the pharmacological modulation of asymmetric dimethylarginine in human disease. When the terminal nitrogens of the guanidine portion of an arginine become methylated through the action of N-methyl transferases, two chemically close, but physiologically different amino acids are synthesized: symmetric and asymmetric dimethylarginine. The vascular origin of asymmetric dimethylarginine and its inhibitory activity on endothelial nitric oxide synthase give it an important role in certain diseases in which microcirculation is compromised: hypertension, atherosclerosis, inflammatory bowel disease, and diabetes. This review discusses the role th…
Anaesthetic techniques to prevent perioperative stroke.
2013
Different techniques and interventions that can be used by an anaesthesiologist to minimize the perioperative stroke risk are summarized.The most important risk factors for perioperative stoke are not modifiable, for example previous stroke or renal failure, but they can be used to identify patients with a high risk for perioperative stroke. The antiplatelet therapy should be continued in patients with a high risk for cardiovascular thrombosis. This might be true even for operations in which bleeding should be strictly avoided such as eye surgery. One of the most recent neuroprotective approaches is the remote ischaemic preconditioning.Perioperative stroke increases morbidity and mortality …
The 2015 International Society for Heart and Lung Transplantation Guidelines for the management of fungal infections in mechanical circulatory suppor…
2016
Shahid Husain, MD, MS, Amparo Sole, MD, PhD, Barbara D. Alexander, MD, MHS, Saima Aslam, MD, MS, Robin Avery, MD, Christian Benden, MD, Eliane M. Billaud, PharmD, PhD, Daniel Chambers, MBBS, MD, Lara Danziger-Isakov, MD, Savitri Fedson, MD, Kate Gould, MD, Aric Gregson, MD, Paolo Grossi, MD, PhD, Denis Hadjiliadis, MD, Peter Hopkins, MD, Me-Linh Luong, MD, Debbie J.E. Marriott, MD, Victor Monforte, MD, Patricia Munoz, MD, PhD, Alessandro C. Pasqualotto, MD, PhD, Antonio Roman, MD, Fernanda P. Silveira, MD, Jeffrey Teuteberg, MD, MS, Stephen Weigt, MD, Aimee K. Zaas, MD, MHS, Andreas Zuckerman, MD, and Orla Morrissey, MD, PhD
Brain tissue pO2 related to SjvO2, ICP, and CPP in severe brain injury
2000
The aim of this report is to present first experience in comparing the course of brain tissue oxygen pressure values (PtiO2) to changes in jugular vein oxygen saturation (SjvO2), intracranial pressure (ICP), and cerebral perfusion pressure (CPP) after severe brain injury. PtiO2 monitoring was done using a polarographic Clark type microcatheter (LICOX pO2 probe) (GMS, Kiel, Germany) with a diameter of 0.5 mm and a sensitive area 7.9 mm long inserted in a right frontal position. The microcatheter was connected to a LICOX pO2 device. A fiber-optic catheter was used to measure SjvO2 and placed into the right internal jugular vein. The ICP monitoring was performed with a fiber-optic intraparench…
A new principle to normalize plasma concentrations allowing single-sample clearance determinations in both children and adults.
1992
A sufficiently accurate quantification of renal function requiring only one plasma sample without an additional gamma-camera study has, until now, only been possible in adults. A new principle will be presented here allowing the universal application of known algorithms, regardless of the clearance substance used, by normalizing the plasma concentrations with respect to the individual body dimensions of the patients - for infants as well as for adults. In this respect, algorithms are developed for clearance determinations using technetium-99m mercaptoacetyltriglycine (99mTc-MAG3), which are based on steady-state studies as the reference. They allow the calculation of quantitative clearance …
Periodontal morphological microcirculation in Oral Lichen Planus
2008
This study aimed at evaluating possible differences in the vascular pattern (of periodontal mucosa microcirculation) between healthy patients and patients suffering from PLP (periodontal lichen planus). Fifty-four patients (27 patients suffering from PLP and 27 healthy patients) were examined by means of videocapillaroscopy. The following area was examined for each patient: periodontal mucosa corresponding to 1.1 and 2.1. The following parameters were analyzed on every capillaroscopic image: capillary loop length, loop diameter, capillary tortuosity, capillary density, avascular areas, possible microhaemorrhages, distinctive morphology. The results obtained using videocapillaroscopic softwa…