100,930 research outputs found
Characterization of the physical and structural changes undergone by a biological tissue during microwave thermal ablation procedures
No full textThe aim of the present doctoral project was to investigate the physical and structural changes occurring in biological tissue treated with microwave thermal ablation procedures, focusing the study on the evaluation and characterization of the shrinkage of the tissue, in correlation with the influence of the thermal changes.
When the project started in 2013, few studies were conducted to comprehend the shrinking phenomenon (Diaz et al., 2008, Brace et al., 2009, Ganguli et al., 2008, Planché et al., 2013, Brace et al., 2010]. Nevertheless, the subject was of high interest for physicians and scientists involved in this field. The results reported from preliminary studies underlined that the volume occupied by the ablated tissue as measured at the end of the thermal ablation procedure is smaller than the volume occupied by the equivalent untreated tissue. Therefore, it resulted important to be able to adequately characterize the shrinkage of the tissue during a microwave thermal ablation procedure in order to correctly predict the true treatment volume; otherwise, the treatment safety as well as the efficacy can be compromised exposing peripheral structures to unwanted heating and affecting the assessment of the treatment’s technical success.
The analysis and study of the thermally ablated tissue led mainly to perform extensive experimental investigations. Accordingly, ex vivo studies were conducted at four different laboratories: the Laboratory of the Division of Health Protection Technologies, ENEA Casaccia Research Centre, Rome (Italy); the Radiology Dept. of Regina Elena National Cancer Institute, Rome (Italy); the R&D laboratory of HS Hospital Service SpA, Aprilia (Italy); the Applied Radiology Laboratory of Hadassah Hebrew University Medical Center, Jerusalem (Israel), where I stayed for 6 months as visiting scholar.
Moreover, thanks to the COST support, the laboratory of the Institute of Microbiology of the Academy of Sciences, Prague (Czech Republic), hosted me during a Short Term Scientific Mission (STSM) to conduct in vivo experiments of dielectric spectroscopy in the framework of a newborn joint scientific collaboration.
In the present thesis, the conducted work is illustrated following the speculative project development. Specifically, the first chapter introduces the microwave ablation therapy, its operating principles, clinical and experimental applications and gaps; the second chapter concerns the used devices and the setups developed to conduct the experimental trials; and the third chapter illustrates the conducted experiments and their results. Finally, the outcomes are discussed in the conclusive chapter
Height and survival at older ages among men born in an inland village in Sardinia (Italy), 1866-2006
No full textThis study investigated the relationship between individual height and survival at older ages among conscripts born between 1866 and 1915 in an inland village of Sardinia, Italy. Individual age at death was related to military height measurement at age 20. Differential longevity of conscripts at older ages was investigated through the comparison of age-specific mortality rates and life expectancy estimates. Results indicated that short conscripts (<161.1 cm) generally had higher survival rates than their tall peers (≥161.1 cm). At 70 years of age, tall peers were expected to live two years less than short conscripts. Biological mechanisms were examined in relation to the greater longevity of shorter people. Copyright © Society for the Study of Social Biology 2012
Letter, [Author unclear] to Paulina T. Merritt
No full textHandwritten letter to Paulina Merritt from an unknown author, October 1, 1876.
Development of an HPTLC method for determination of hypoglycin A in aqueous extracts of seedlings and samaras of Acer species.
No full textHypoglycin A (HGA) is a toxin contained in seeds of the sycamore maple tree (Acer pseudoplatanus). Ingestion of this amino acid causes equine atypical myopathy (AM) in Europe. Another variety, A. negundo, is claimed to be present where AM cases were reported in the US. For unknown reasons, occurrence of this disease has increased. It is important to define environmental key factors that may influence toxicity of samaras from Acer species. In addition, the content of HGA in seedlings needs to be determined since AM outbreaks, during autumn period when the seeds fall but also during spring when seeds are germinating. The present study aims to validate a reliable method using high performance thin layer chromatography for determination and comparison of HGA in samaras and seedlings.
The working range of the method was between 20 μg HGA to 408 μg HGA per ml water, corresponding to 12 - 244 mg/kg fresh weight or 40 - 816 mg/kg dry weight, taking into account of an arbitrary average dry matter content of 30%. Instrumental limit of detection and limit of quantification were of 10 µg HGA/ml and 20 µg HGA/ml water, respectively. Instrumental precision was 4% (RSD on 20 repeated measurements) while instrumental accuracy ranged between 86% and 121% of expected value. The HGA recovery of the analytical method estimated from spiked samaras and seedlings samples ranged between 63 and 103%. The method was applied to 9 samples of samaras from Acer pseudoplatanus, A. platanoides and A. campestre and 5 seedlings samples from A. pseudoplatanus. The results confirm detection of HGA in samaras from A. pseudoplatanus and the absence of detection in samaras of other tested species. They also suggest that detected levels of HGA are highly variable. This confirmed the suitability of the method for HGA detection in samaras or seedling
Handwritten biographical information on Paulina T. McClung Merritt
No full textA handwritten biography of Paulina T. McClung Merritt by an unknown author, 1892.
Heterogeneous and tissue-specific regulation of effector T cell responses by IFN-gamma during Plasmodium berghei ANKA infection.
No full textIFN-γ and T cells are both required for the development of experimental cerebral malaria during Plasmodium berghei ANKA infection. Surprisingly, however, the role of IFN-γ in shaping the effector CD4(+) and CD8(+) T cell response during this infection has not been examined in detail. To address this, we have compared the effector T cell responses in wild-type and IFN-γ(-/-) mice during P. berghei ANKA infection. The expansion of splenic CD4(+) and CD8(+) T cells during P. berghei ANKA infection was unaffected by the absence of IFN-γ, but the contraction phase of the T cell response was significantly attenuated. Splenic T cell activation and effector function were essentially normal in IFN-γ(-/-) mice; however, the migration to, and accumulation of, effector CD4(+) and CD8(+) T cells in the lung, liver, and brain was altered in IFN-γ(-/-) mice. Interestingly, activation and accumulation of T cells in various nonlymphoid organs was differently affected by lack of IFN-γ, suggesting that IFN-γ influences T cell effector function to varying levels in different anatomical locations. Importantly, control of splenic T cell numbers during P. berghei ANKA infection depended on active IFN-γ-dependent environmental signals--leading to T cell apoptosis--rather than upon intrinsic alterations in T cell programming. To our knowledge, this is the first study to fully investigate the role of IFN-γ in modulating T cell function during P. berghei ANKA infection and reveals that IFN-γ is required for efficient contraction of the pool of activated T cells
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Pelevin’s Trinity in the novel “t”: author – protagonist – reader
No full textThe article attempts to interpret Pelevin's artistic strategy in the novel "T" by exploring its subject organization and addressing the key problems of the author, the protagonist, and the reader as they are seen by the researcher. The article analyzes the peculiarities of constructing the narrative reality in the novel "T", and goes on to discuss Pelevin's philosophic models of the development of the humankind, and the emergence of his new anthropology
Measuring industry-science links through inventor-author relations: A profiling method
No full textIn this pilot study we examine the performance of text-based profiling in recovering a set of validated inventor-author links. In a first step we match patents and publications solely based on their similarity in content. Next, we compare inventor and author names on the highest ranked matches for the occurrence of name matches. Finally, we compare these candidate matches with the names listed in a validated set of inventor-author names. Our text-based profile methodology performs significantly better than a random matching of patents and publications, suggesting that text-based profiling is a valuable complementary tool to the name searches used in previous studies.innovation; industry-science links; text-based profiling;
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