923 research outputs found

    Geomorphological evolution of western Sicily, Italy

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    This paper proposes a morphoevolutionary model for western Sicily. Sicily is a chain–foredeep–foreland ­system still being built, with tectonic activity involving uplift which tends to create new relief. To reconstruct the ­morphoevolutionary model, geological, and geomorphological studies were done on the basis of field survey and aerial photographic interpretation. The collected data show large areas characterized by specific geological, geomorphological, and topographical settings with rocks, landforms, and landscapes progressively older from south to north Sicily. The achieved results display: (1) gradual emersion of new areas due to uplift, its interaction with the Quaternary ­glacio-eustatic oscillations of the sea level, and the following production of a flight of stair-steps of uplifted marine ­terraces in southern Sicily, which migrates progressively upward and inwards; in response to the uplift (2) triggering of down-cutting processes that gradually dismantle the oldest terraces; (3) competition between uplift and down-cutting processes, which is responsible for the genesis of river valleys and isolated rounded hills in central Sicily; (4) continuous deepening over time that results in the exhumation of older and more resistant rocks in northern Sicily, where the higher heights of Sicily are realized and the older forms are retained; (5) extensional tectonic event in the northern end of Sicily, that produces the collapse of large blocks drowned in the Tyrrhenian Sea and sealed by coastal-marine deposits during the Calabrian stage; (6) trigger of uplift again in the previously subsiding blocks and its interaction with coastal processes and sea level fluctuations, which produce successions of marine terraces during the Middle–Upper Pleistocene stages

    Preclinical Imaging Evaluation of miRNAs' Delivery and Effects in Breast Cancer Mouse Models: A Systematic Review

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    SIMPLE SUMMARY: The purpose of this systematic review was to assess the advancements in preclinical molecular imaging protocols used to study the delivery, tracking and therapeutic efficacy of miRNAs in mouse models of breast cancer. For this aim we have interrogated several browsers (PubMed, EMBASE, BIOSIS™ and Scopus) using the following terms: breast cancer, mouse, mice, microRNA(s) and miRNA(s). From 114 articles selected according to a PRISMA protocol, we focused on mouse models, routes of miRNA administration, therapy efficacy and molecular imaging. Importantly, we highlight here the advancements made in all imaging techniques’ applications used, providing a useful tool, on the basis of the current evidence, with which to suggest the best preclinical imaging protocol. ABSTRACT: Background: We have conducted a systematic review focusing on the advancements in preclinical molecular imaging to study the delivery and therapeutic efficacy of miRNAs in mouse models of breast cancer. Methods: A systematic review of English articles published in peer-reviewed journals using PubMed, EMBASE, BIOSIS™ and Scopus was performed. Search terms included breast cancer, mouse, mice, microRNA(s) and miRNA(s). Results: From a total of 2073 records, our final data extraction was from 114 manuscripts. The most frequently used murine genetic background was Balb/C (46.7%). The most frequently used model was the IV metastatic model (46.8%), which was obtained via intravenous injection (68.9%) in the tail vein. Bioluminescence was the most used frequently used tool (64%), and was used as a surrogate for tumor growth for efficacy treatment or for the evaluation of tumorigenicity in miRNA-transfected cells (29.9%); for tracking, evaluation of engraftment and for response to therapy in metastatic models (50.6%). Conclusions: This review provides a systematic and focused analysis of all the information available and related to the imaging protocols with which to test miRNA therapy in an in vivo mice model of breast cancer, and has the purpose of providing an important tool to suggest the best preclinical imaging protocol based on available evidence

    Role of fluorine in suppressing boron transient enhanced diffusion in preamorphized Si

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    We have explained the role of fluorine in the reduction of the self-interstitial population in a preamorphized Si layer under thermal treatment. For this purpose, we have employed a B spike layer grown by molecular-beam epitaxy as a marker for the self-interstitial local concentration. The amorphized samples were implanted with 731012, 731013, or 431014 F/cm2 at 100 keV, and afterwards recrystallized by solid phase epitaxy. Thermal anneals at 750 or 850 °C were performed in order to induce the release of self-interstitials from the end-of-range (EOR) defects and thus provoke the transient enhanced diffusion of B atoms. We have shown that the incorporation of F reduces the B enhanced diffusion in a controlled way, up to its complete suppression. It is seen that no direct interaction between B and F occurs, whereas the suppression of B enhanced diffusion is related to the F ability in reducing the excess of silicon self-interstitials emitted by the EOR source. These results are reported and discussed

    Clinical Appropriateness of Coronary Angiography

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    Background: The study evaluates the appropriateness of coronary angiography and the agreement between the used method and the presence of coronary artery disease by the indications proposed from American College of Cardiology/American Heart Association (1999). Method: The guidelines allow us to associate to Class I and IIa the judgment of appropriateness, to the Class IIb of uncertainty; to Class III of inappropriateness. Result: On 761 coronary angiography 76.74% were appropriate, 23.13% unsuitable, 0.13% uncertain. The group with the greater value of appropriateness is that one with unstable angina (97.9% appropriate); that one with the lower value is the group with non-specific symptomatology (26.7% appropriate). Conclusion: Considering the false positives, it is important the rate of the greater sensibility and the lower specificity of the not invasive tests carried before coronary angiography, as well as, the probable presence of microcircle disease. Among the false negatives, we must considered the number of patients with effective coronary artery disease which has “jumped” the intermediate stage of the not invasive diagnostic process, before the coronary angiography, but have obtained the same final benefit
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