One-dimensional modelling of mixing, dispersion and segregation of multiphase fluids flowing in pipelines

The flow of immiscible liquids in pipelines has been studied in this work in order to formulate a one-dimensional model for the computer analysis of two-phase liquid-liquid flow in horizontal pipes. The model simplifies the number of flow patterns commonly encountered in liquid-liquid flow to stratified flow, fully dispersed flow and partial dispersion with the formation of one or two different emulsions. The model is based on the solution of continuity equations for dispersed and continuous phase; correlations available in the literature are used for the calculation of the maximum and mean dispersed phase drop diameter, the emulsion viscosity, the phase inversion point, the liquid-wall friction factors, liquid-liquid friction factors at interface and the slip velocity between the phases. In absence of validated models for entrainment and deposition in liquid-liquid flow, two entrainment rate correlations and two deposition models originally developed for gas-liquid flow have been adapted to liquid-liquid flow. The model was applied to the flow of oil and water; the predicted flow regimes have been presented as a function of the input water fraction and mixture velocity and compared with experimental results, showing an overall good agreement between calculation and experiments. Calculated values of oil-in-water and water-in-oil dispersed fractions were compared against experimental data for different oil and water superficial velocities, input water fractions and mixture velocities. Pressure losses calculated in the full developed flow region of the pipe, a crucial quantity in industrial applications, are reasonably close to measured values. Discrepancies and possible improvements of the model are also discussed. The model for two-phase flow was extended to three-phase liquid-liquid-gas flow within the framework of the two-fluid model. The two liquid phases were treated as a unique liquid phase with properly averaged properties. The model for three-phase flow thus developed was implemented in an existing research code for the simulation of three-phase slug flow with the formation of emulsions in the liquid phase and phase inversion phenomena. Comparisons with experimental data are presented

HEAT SHOCK PROTEINS AND AUTOIMMUNE SYSTEM ACTIVATION IN IBD: ARTICULAR MANIFESTATIONS AND THE EPIDEMIOLOGICAL FREQUENCY IN ORTHPEDICS

clinical evidence suggest that arthritis is one of the complications of inflammatori bowel disease (IBD) of which the etiological causes are still not completely understood. Among the possible explanations the most probable theory is poor regulation of the intestinal immune system, which causes a cross-like immune reactivity against the resident micro flora. Arthritis is these subjects involves different joints and is asymmetric, with greater involvement of the large joints of the lower limbs. Joints may also be involved with the spinal forms of sacroileitis and ankilosing spondylitis. This clinical evidence explains the existence of Lesnioski-Crohn's disease, a variant of IBD in which patients have bone joint problems that may also be the primary manifestations of the disease

3D-Printing of Arteriovenous Malformations for Radiosurgical Treatment: Pushing Anatomy Understanding to Real Boundaries

open9noRadiosurgery of arteriovenous malformations (AVMs) is a challenging procedure. Accuracy of target volume contouring is one major issue to achieve AVM obliteration while avoiding disastrous complications due to suboptimal treatment. We describe a technique to improve the understanding of the complex AVM angioarchitecture by 3D prototyping of individual lesions. Arteriovenous malformations of ten patients were prototyped by 3D printing using 3D rotational angiography (3DRA) as a template. A target volume was obtained using the 3DRA; a second volume was obtained, without awareness of the first volume, using 3DRA and the 3D-printed model. The two volumes were superimposed and the conjoint and disjoint volumes were measured. We also calculated the time needed to perform contouring and assessed the confidence of the surgeons in the definition of the target volumes using a six-point scale. The time required for the contouring of the target lesion was shorter when the surgeons used the 3D-printed model of the AVM (p=0.001). The average volume contoured without the 3D model was 5.6 ± 3 mL whereas it was 5.2 ± 2.9 mL with the 3D-printed model (p=0.003). The 3D prototypes proved to be spatially reliable. Surgeons were absolutely confident or very confident in all cases that the volume contoured using the 3D-printed model was plausible and corresponded to the real boundaries of the lesion. The total cost for each case was 50 euros whereas the cost of the 3D printer was 1600 euros. 3D prototyping of AVMs is a simple, affordable, and spatially reliable procedure that can be beneficial for radiosurgery treatment planning. According to our preliminary data, individual prototyping of the brain circulation provides an intuitive comprehension of the 3D anatomy of the lesion that can be rapidly and reliably translated into the target volume.openCONTI, Alfredo; PONTORIERO, ANTONIO; IATI', GIUSEPPE; MARINO, DANIELE; LA TORRE, Domenico; VINCI, Sergio Lucio; GERMANO', Antonino Francesco; PERGOLIZZI, Stefano; TOMASELLO, FrancescoCONTI, Alfredo; PONTORIERO, ANTONIO; IATI', GIUSEPPE; MARINO, DANIELE; LA TORRE, Domenico; VINCI, Sergio Lucio; GERMANO', Antonino Francesco; PERGOLIZZI, Stefano; TOMASELLO, Francesc

INFLAMMATORY BOWEL DISEASE AND PERIPHERAL ATRHITIS: MESALAZINA AND PROBIOTICS

The inflammaotory bowel disease (IBD) are a group of inflammatory pathologies of the digestive line with chronicity and recurrent characteristic. The IBDs mostly recognized are the ulcerative colitis and Crohn's disease; they are more frequent in the industrialized countries and among the caucasian populations that among those africans or oriental. The secondary artropaties to IBD recognize a multifactorial genesis in subjects predisposed as a result genetically or environmental factors; a fundamental role of the intestinal dysbiosis they are hypothesized

Post-Treatment Edema after Meningioma Radiosurgery is a Predictable Complication

Symptomatic post-treatment edema (PTE) causing seizures, focal deficits, and intracranial hypertension is a rather common complication of meningioma radiosurgery. Factors associated to the occurrence of PTE still needs to be clarified. We retrospectively analyzed our patients' data to identify factors associated with the development of symptomatic PTE. Supposed risk factors were systematically analyzed. Between July 2007 and March 2014, 245 meningiomas in 229 patients were treated by a single fraction or multisession radiosurgery (2-5 fractions) or hypofractionated stereotactic radiotherapy (6-15 fractions) using the CyberKnife system (Accuray Inc., Sunnyvale, CA) at the University Hospital of Messina, Italy. Local tumor control was achieved in 200 of 212 patients with World Health Organization (WHO) Grade I meningiomas (94%) at a mean follow-up of 62 months. Symptomatic PTE on MRI was diagnosed in 19 patients (8.3%) causing seizure (n=17, 89%), aggravating headache (n=12, 63%), or focal deficits (n=13, 68%). Four variables were found to be associated with the likelihood of edema development, including tumor volume > 4.5 mL, non-basal tumor location, tight brain/tumor interface, and atypical histology. Nonetheless, when multivariate logistic regression analysis was performed, only tumor volume and brain-tumor interface turned out to be independent predictors of PTE development. Our results suggest that the factor associated with the risk of developing PTE is associated to characteristics of meningioma rather than to the treatment modality used. Accordingly, an appropriate patient selection is the way to achieve safe treatment and long-term disease control

Combination therapy with aliskiren versus ramipril or losartan added to conventional therapy in patients with type 2 diabetes mellitus, uncontrolled hypertension and microalbuminuria.

Hypothesis/Introduction: The aim of this study was to assess the antihypertensive efficacy and safety of aliskiren versus ramipril or losartan in hypertensive patients with type 2 diabetes mellitus, microalbuminuria and uncontrolled hypertension, despite the use of optimal conventional antihypertensive therapy. Materials and methods: In this open-label active comparator study, 126 patients were randomly assigned to receive 24 weeks of additional therapy with aliskiren (Group A) or either losartan or ramipril (Group B), according to whether a patient was already treated with an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker, respectively. Results: After 24 weeks, both treatment groups experienced a significant reduction of systolic blood pressure (−11.37% and −8.47%, respectively; both p <0.001 vs . baseline) and diastolic blood pressure levels (−10.67% and −9.28%, respectively; both p <0.001 vs . baseline), with a greater reduction of mean systolic values in Group A compared with Group B ( p <0.001). Furthermore, after six months microalbuminuria was significantly decreased in both treatment groups (−67.62% and −49.1%, respectively; both p <0.001), with a reduction rate in Group A significantly higher than in Group B ( p <0.001). Conclusions: The addition of aliskiren to optimal conventional therapy provided a higher reduction of blood pressure and urinary albumin excretion when compared with the addition of losartan or ramipril

A misunderstood intestinal perforation believed acute pancreatitis: a case report

Acute pancreatitis represents one, possible but rare, of the several complications of laparoscopic cholecystectomy. In the case reported, a 31-year-old female patient complained of abdominal pain after laparoscopic cholecystectomy. The clinical picture, the high values of serum amylase, lipase and white blood cell count and the subsequent abdominal computed tomography (CT) led to diagnose an acute biliary pancreatitis. This was pharmacologically treated, but the patient worsened in a few days. A contrastenhanced CT showed the presence of free air and effusion into the peritoneal cavity. The patient was submitted to another intervention, which revealed a 1-cm jejunal perforation. The injured loop was then repaired and the patient discharged after three days. The cause remains obscure but it was likely due to umbilical trocar insertion. An upper quadrant abdominal pain with elevated amylase and lipase serum concentration, not always indicate the presence of an acute pancreatitis but could be associated to a difficult case of intestinal perforation