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    Earthquake‐induced landslide scenarios for seismic microzonation. Application to the Accumoli area (Rieti, Italy)

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    Scenarios of earthquake-induced landslides are necessary for seismic microzonation (SM) studies since they must be integrated with the mapping of instability areas. The PARSIFAL (Probabilistic Approach to pRovide Scenarios of earthquake‐Induced slope FAiLures) approach provides extensive analyses, over tens to thousands of square kilometers, and is designed as a fully comprehensive methodology to output expected scenarios which depend on seismic input and saturation conditions. This allows to attribute a rating, in terms of severity level, to the landslide-prone slope areas in view of future engineering studies and designs. PARSIFAL takes into account first-time rock- and earth-slides as well as re-activations of existing landslides performing slope stability analyses of different failure mechanisms. The results consist of mapping earthquake-induced landslide scenarios in terms of exceedance probability of critical threshold values of co-seismic displacements (P[D≥Dc|a(t),ay]). PARSIFAL was applied in the framework of level 3 SM studies over the municipality area of Accumoli (Rieti, Italy), strongly struck by the 2016 seismic sequence of Central Apennines. The use of the PARSIFAL was tested for the first time to screen the Susceptibility Zones (ZSFR) from the Attention Zones (ZAFR) in the category of the unstable areas, according to the guidelines by Italian Civil Protection. The results obtained were in a GIS-based mapping representing the possibility for a landslide to be induced by an earthquake (with a return period of 475 years) in three different saturation scenarios (i.e. dry, average, full). Only 41% of the landslide-prone areas in the Municipality of Accumoli are existing events, while the remaining 59% is characterized by first-time earth- or rock-slides. In dry conditions, unstable conditions or P[D≥Dc|a(t),ay]>0 were for 54% of existing landslides, 17% of first-time rock-slides and 1% of first-time earth- slides. In full saturation conditions, the findings are much more severe since unstable conditions or P[D≥Dc|a(t),ay]>0 were found for 58% of the existing landslides and for more than 80% of first-time rock- and earth-slides. Moreover, comparison of the total area of the ZAFR versus ZSFR, resulted in PARSIFAL screening reducing of 22% of the mapped ZAFR

    Measuring disease activity in Crohn's disease

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    In the last few years the management of Crohn's disease (CD) has changed due to the introduction of new therapeutic agents that provide more alternative options in patients with severe diseases, introducing new concepts regarding treatment timing. At the moment, the absence of good predictors of disease outcome and a subclinical marker available to predict relapse during clinical remission are major problems in the management of CD. In recent decades, the evaluation of several variables has been proposed to address this issue, including disease behavior, clinical-endoscopic activity and intestinal damage. In particular, definition of mucosal restitution or healing after therapy has been proposed as a surrogate of efficacy and new goal of the therapy. Regarding this concept, several criticisms have been raised, such as the need to better define the role of mucosal healing in a transmural disease. In order to address this issue, new alternative techniques providing both extraluminal and luminal intestinal damage have been proposed, including ultrasonography, computed tomography and magnetic resonance imaging. © 2012 Springer Science+Business Media, LLC

    Taxa de adequação de uso das terras e riscos de degradação agroambiental.

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    Ainda há grandes conflitos entre agricultura e meio ambiente, apesar da crescente adoção de sistemas de produção mais adequados à conservação dos recursos naturais. O objetivo deste trabalho foi analisar a taxa de adequação de uso das terras da quadrícula de Ribeirão Preto-SP, identificando-se inclusive as taxas de sobreutilização e subutilização, além de eventuais riscos de degradação agroambiental. A partir do cruzamento do mapa de uso atual das terras com o mapa de aptidão agrícola foi gerado o mapa de adequação de uso. A área apresentou uso adequado para 50,76% das terras; subutilização para 28,67%; e sobreutilização para 13,99%. De um modo geral a área apresentou risco baixo ou muito baixo de degradação agroambiental

    Severity of postoperative recurrence in Crohn's disease: Correlation between endoscopic and sonographic findings

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    Background: Crohn's disease (CD) recurrence is currently assessed by ileocolonoscopy. Small intestine contrast ultrasonography (SICUS) visualizes the small bowel lesions in CD, although its role after curative resection is undefined. We aimed to investigate the accuracy of SICUS in assessing CD recurrence after ileocolonic resection when using ileocolonoscopy as a gold standard. The correlation between the bowel wall thickness (BWT) measured by SICUS and the endoscopic score of recurrence was also assessed. Methods: The analysis included 72 CD patients with ileocolonic resection requiring ileocolonoscopy, undergoing SICUS within 6 months. Recurrence was assessed by ileocolonoscopy using the Rutgeerts' score. SICUS was performed after PEG ingestion and findings compatible with recurrence included: increased BWT (>3 mm), bowel dilation (>25 mm) or stricture (<10 mm). Results: Ileocolonoscopy detected recurrence in 67/72 (93%) patients. SICUS detected findings compatible with recurrence in 62/72 (86%) patients (5 false negative (FN), 4 false positive (FP), 1 true negative (TN), 62 true positive (TP)), showing a 92.5% sensitivity, 20% specificity, and 87.5% accuracy for detecting CD recurrence. The BWT detected by SICUS was correlated with the Rutgeerts' score (P = 0.0001; r = 0.67). The median BWT, the extent of the ileal lesions, and the prestenotic dilation were higher in patients with an endoscopic degree of recurrence ≥3 versus ≤2 (P < 0.001) and the lumen diameter was lower in patients with a Rutgeerts' score ≥3 versus ≤2 (P < 0.0001). Conclusions: Although SICUS and ileocolonoscopy provide different views of the small bowel, SICUS shows a significant correlation with the endoscopic findings. SICUS may represent an alternative noninvasive technique for assessing CD recurrence after ileocolonic resection. Copyright © 2009 Crohn's & Colitis Foundation of America, Inc

    An Intact Kidney Slice Model to Investigate Vasa Recta Properties and Function in situ

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    Background: Medullary blood flow is via vasa recta capillaries, which possess contractile pericytes. In vitro studies using isolated descending vasa recta show that pericytes can constrict/dilate descending vasa recta when vasoactive substances are present. We describe a live kidney slice model in which pericyte-mediated vasa recta constriction/dilation can be visualized in situ. Methods: Confocal microscopy was used to image calcein, propidium iodide and Hoechst labelling in ‘live’ kidney slices, to determine tubular and vascular cell viability and morphology. DIC video-imaging of live kidney slices was employed to investigate pericyte-mediated real-time changes in vasa recta diameter. Results: Pericytes were identified on vasa recta and their morphology and density were characterized in the medulla. Pericyte-mediated changes in vasa recta diameter (10–30%) were evoked in response to bath application of vasoactive agents (norepinephrine, endothelin-1, angiotensin-II and prostaglandin E2) or by manipulating endogenous vasoactive signalling pathways (using tyramine, L-NAME, a cyclo-oxygenase (COX-1) inhibitor indomethacin, and ATP release). Conclusions: The live kidney slice model is a valid complementary technique for investigating vasa recta function in situ and the role of pericytes as regulators of vasa recta diameter. This technique may also be useful in exploring the role of tubulovascular crosstalk in regulation of medullary blood flow

    Non-invasive techniques for assessing postoperative recurrence in Crohn's disease

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    Postoperative recurrence after ileo-colonic resection is a feature of Crohn's Disease (CD), almost 73% of patients show endoscopic recurrence at 1 year and 90% at 3 years. After surgical resection for CD, symptoms may be related to the surgical resection itself. Moreover, the development of an early severe endoscopic recurrence within 1 year represents a risk factor for early clinical recurrence. On the basis of these observations, the early detection and assessment of asymptomatic endoscopic recurrence may allow a timely and appropriate treatment of CD patients after ileo-colonic resection. At this purpose, conventional colonoscopy with ileoscopy currently represents the gold standard for assessing CD recurrence, graded according to the Rutgeerts' score. Lesions compatible with CD recurrence can be also detected by conventional radiology, including small bowel follow through and enema, both associated with a high radiation exposure. Due to the ineluctable course of CD after resection, and to the need of a proper follow up for assessing CD recurrence, several alternative, non invasive techniques have been searched in order to assess the post-operative recurrence, including: faecal alpha 1-antitrypsin clearance, faecal calprotectin, 99Tc-HMPAO scintigraphy, virtual colonoscopy, ultrasonography and, more recently, wireless capsule endoscopy (WCE) and Small Intestine Contrast Ultrasonography (SICUS). Among these, current evidences suggest that in experienced hands, ultrasound examination by SICUS represents a non-invasive technique useful for assessing recurrence in CD patients under regular follow up after surgery. The same findings are suggested for WCE, although the impact risk related to the recurrence or to the surgical anastomosis itself limits the use of this non-invasive technique for assessing CD recurrence after surgery. © 2008 Editrice Gastroenterologica Italiana S.r.l

    123I-Interleukin-2 scintigraphy for the in vivo assessment of intestinal mononuclear cell infiltration in Chron's disease

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    Activated mononuclear cells expressing interleukin-2 (IL2) receptors (IL2-Rs) heavily infiltrate the Crohn’s disease (CD) gut wall. A new technique for the in vivo detection of tissue infiltrating IL2-R positive (IL2R1ve) cells was developed based on 123I-IL2 scintigraphy. The aim of this study was to investigate whether 123I-IL2 accumulates in the CD gut wall in different phases of the disease and to evaluate the specificity of 123I-IL2 binding to activated IL2R1ve cells infiltrating the gut wall. Methods: Fifteen patients with ileal CD (10 active and 5 inactive) and 10 healthy volunteers were studied by 123I-IL2 scintigraphy. Six patients with active CD were studied before and after 12 wk of steroid treatment. After scintigraphy, patients were followed up for 29–54 mo. Ex vivo autoradiography was performed to determine specificity of 125IIL2 binding to IL2R1ve cells. For bowel scintigraphy, 123I-IL2 (75 MBq) was injected intravenously and g camera images were acquired after 1 h. Bowel radioactivity was quantified in 64 regions of interest (ROIs). Results: Autoradiography showed specific binding of 125I-IL2 to IL2R1ve mononuclear cells infiltrating the CD gut wall. Intestinal 123I-IL2 uptake assessed by the number of positive ROIs was higher in patients with active or inactive CD than in healthy volunteers (P , 0.0001 andP 5 0.03, respectively) and positively correlated with the CD activity index (P 5 0.01). 123I-IL2 intestinal uptake significantly decreased in patients with CD in steroid-induced remission (P 5 0.03). A significant correlation was observed between the number of positive ROIs and time to disease relapse. Conclusion: 123I-IL2 accumulates in the diseased CD gut wall by specific binding to IL2R1ve cells, infiltrating the involved tissues. 123I-IL2 scintigraphy may be an objective tool for the in vivo assessment of intestinal activated mononuclear cell infiltration

    Wireless capsule endoscopy and proximal small bowel lesions in Crohn's disease

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    AIM: To investigate the prevalence of proximal small bowel (SB) lesions detected by wireless capsule endoscopy (WCE) in Crohn's disease (CD). METHODS: WCE was performed in 64 patients: 32 with CD of the distal ileum, and 32 controls with iron-deficiency anemia (IDA) or diarrhea. WCE was performed using the Given SB-WCE, followed by small intestine contrast ultrasonography (SICUS). Findings compatible with CD by using WCE included erosions, aphthoid or deep ulcers, and strictures/stenosis. RESULTS: WCE detected proximal SB lesions in 16/32 (50%) patients (14 aphthoid ulcers, 2 deep ulcers, one stricture), which appeared not to be related to clinical parameters [epigastric pain, age, smoking, non-steroidal anti-inflammatory drugs (NSAIDs), IDA]. Among patients with proximal SB lesions, 6 (37%) were smokers, 3 (19%) NSAID users, 3 (19%) had epigastric pain and 4 (25%) had IDA. SICUS detected proximal SB lesions in 3/32 patients (19%) also showing lesions with WCE. No correlations were observed between proximal SB lesions assessed by WCE or by SICUS (χ2 = 1.5, P = 0.2). CONCLUSION: The use of WCE allows the detection of previously unknown upper SB lesions in a high proportion of patients with a previous diagnosis of CD involving the distal ileum. © 2010 Baishideng

    Time-domain nuclear magnetic resonance (TD-NMR) and chemometrics for determination of fat content in commercial products of milk powder.

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    Made available in DSpace on 2017-11-09T23:16:05Z (GMT). No. of bitstreams: 1 PROCITimedomainnuclear....pdf: 1135929 bytes, checksum: 473b2dd2b69ad9452455ae6850aa087f (MD5) Previous issue date: 2017-11-09bitstream/item/166525/1/PROCI-Time-domain-nuclear....pd
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