111 research outputs found
Nonlinear light-matter interaction at terahertz frequencies
Strong optical pulses at mid-infrared and terahertz frequencies have recently
emerged as a powerful tool to manipulate and control the solid state and
especially complex condensed matter systems with strongly correlated electrons.
The recent developments in high-power sources in the 0.1-30 THz frequency
range, both from table-top laser systems and Free-Electron Lasers, has provided
access to excitations of molecules and solids, which can be stimulated at their
resonance frequencies. Amongst these, we discuss free electrons in metals,
superconducting gaps and Josephson plasmons in layered superconductors,
vibrational modes of the crystal lattice (phonons), as well as magnetic
excitations. This Review provides an overview and illustrative examples of how
intense THz transients can be used to resonantly control matter, with
particular focus on strongly correlated electron systems and high-temperature
superconductors.Comment: 55 pages, 34 figure
Virtual biopsy in abdominal pathology: where do we stand?
In recent years, researchers have explored new ways to obtain information from pathological tissues, also exploring non-invasive techniques, such as virtual biopsy (VB). VB can be defined as a test that provides promising outcomes compared to traditional biopsy by extracting quantitative information from radiological images not accessible through traditional visual inspection. Data are processed in such a way that they can be correlated with the patient’s phenotypic expression, or with molecular patterns and mutations, creating a bridge between traditional radiology, pathology, genomics, and artificial intelligence (AI). Radiomics is the backbone of VB, since it allows the extraction and selection of features from radiological images, feeding them into AI models in order to derive lesions' pathological characteristics and molecular status. Presently, the output of VB provides only a gross approximation of the findings of tissue biopsy. However, in the future, with the improvement of imaging resolution and processing techniques, VB could partially substitute the classical surgical or percutaneous biopsy, with the advantage of being non-invasive, comprehensive, accounting for lesion heterogeneity, and low cost. In this review, we investigate the concept of VB in abdominal pathology, focusing on its pipeline development and potential benefits
Virtual biopsy in prostate cancer: can machine learning distinguish low and high aggressive tumors on MRI?
In the last decades, MRI was proven a useful tool for the diagnosis and characterization of Prostate Cancer (PCa). In the literature, many studies focused on characterizing PCa aggressiveness, but a few have distinguished between low-aggressive (Gleason Grade Group (GG) =3) PCas based on biparametric MRI (bpMRI). In this study, 108 PCas were collected from two different centers and were divided into training, testing, and validation set. From Apparent Diffusion Coefficient (ADC) map and T2-Weighted Image (T2WI), we extracted texture features, both 3D and 2D, and we implemented three different methods of Feature Selection (FS): Minimum Redundance Maximum Relevance (MRMR), Affinity Propagation (AP), and Genetic Algorithm (GA). From the resulting subsets of predictors, we trained Support Vector Machine (SVM), Decision Tree, and Ensemble Learning classifiers on the training set, and we evaluated their prediction ability on the testing set. Then, for each FS method, we chose the best classifier, based on both training and testing performances, and we further assessed their generalization capability on the validation set. Between the three best models, a Decision Tree was trained using only two features extracted from the ADC map and selected by MRMR, achieving, on the validation set, an Area Under the ROC (AUC) equal to 81%, with sensitivity and specificity of 77% and 93%, respectively.Clinical Relevance- Our best model demonstrated to be able to distinguish low-aggressive from high-aggressive PCas with high accuracy. Potentially, this approach could help clinician to noninvasively distinguish between PCas that might need active treatment and those that could potentially benefit from active surveillance, avoiding biopsy-related complications
Influência da atividade física em grupo na qualidade de vida e variáveis cardiorrespiratórias em idosos institucionalizados
Introdução: O envelhecimento populacional é um fenômeno relevante em todo mundo, sendo que atenção tem sido dada a qualidade de vida da população idosa. Objetivo: Avaliar os efeitos da atividade física sobre a qualidade de vida de idosos institucionalizados, identificar o perfil desses indivíduos e verificar a influência da atividade física sobre os sinais vitais. Materiais e Métodos: A amostra foi composta por sete indivíduos, de ambos os sexos. O programa de exercícios foi realizado em uma frequência de três vezes semanais no período de um mês. A intervenção foi composta de exercícios de aquecimento, alongamentos, amplitude de movimento ativa, atividades lúdicas e relaxamento. A avaliação foi realizada por meio de um questionário de caracterização da amostra, bem como aplicação do questionário WHOQOL-OLD para avaliar a qualidade de vida, onde foi aplicado pré e pós-intervenção. Os sinais vitais: PAS, PAD, FC, FR, SapO2 foram verificadas pré e pós sessão. Resultados: Verificou-se neste estudo que os participantes apresentavam idade média de 70 anos, sendo a maior prevalência do sexo feminino (86%) e de indivíduos não escolarizados (57%). Em relação ao escore bruto pré e pós intervenção do questionário WHOQOL – OLD, observamos diferença estatisticamente significativa (p<0,05) evidenciando uma melhora na qualidade de vida desta população. Observamos uma redução estatisticamente significativa na PAD, PAS e SpO2 no momento pós-intervenção. Conclusão: Conclui-se assim que o programa de atividade física não proporcionou alterações relevantes clinicamente nos sinais vitais. Destaca-se ainda que a atividade física em grupo proporcionou uma melhora global da qualidade de vida dos idosos institucionalizados
VEGF and VEGFR polymorphisms affect clinical outcome in advanced renal cell carcinoma patients receiving first-line sunitinib
Background: Currently, sunitinib represents one of the therapeutic strongholds for renal cell carcinoma, but the criteria for treatment selection are lacking. We assessed the role of vascular endothelial growth factor (VEGF) and VEGF receptor (VEGFR) polymorphisms in the prediction of the clinical outcome in metastatic renal cell carcinoma (mRCC) patients.Methods:A total of 84 tumour samples from mRCC patients receiving first-line sunitinib were tested for VEGF and VEGFR single-nucleotide polymorphisms (SNPs). The SNP results were correlated with progression-free survival (PFS) and overall survival (OS).Results:Median PFS was 8.22 months, although whereas median OS was 32.13 months. The VEGF A rs833061 resulted significant in PFS (17 vs 4 months; P<0.0001) and OS (38 vs 10 months; P<0.0001). The VEGF A rs699947 was significant for PFS (18 vs 4 months; P=0.0001) and OS (37 vs 16 months; P<0.0001). The VEGF A rs2010963 was significant in PFS (18 vs 8 vs 2 months; P=0.0001) and OS (31 vs 36 vs 9 months; P=0.0045). The VEGR3 rs6877011 was significant in PFS (12 vs 4 months; P=0.0075) and OS (36 vs 17 months; P=0.0001). At multivariate analysis, rs833061, rs2010963 and rs68877011 were significant in PFS, and rs833061 and rs68877011 were independent factors in OS.Conclusions:In our analysis, patients with TT polymorphism of rs833061, CC polymorphism of rs699947, CC polymorphism of rs2010963 and CG polymorphism of rs6877011 seem to have a worse PFS and OS when receiving first-line sunitini
Elevated serum Neurofilament Light chain (NfL) as a potential biomarker of neurological involvement in Myotonic Dystrophy type 1 (DM1)
Background Cognitive and behavioural symptoms due to involvement of the central nervous system (CNS) are among the main clinical manifestations of Myotonic Dystrophy type 1 (DM1). Such symptoms affect patients' quality of life and disease awareness, impacting on disease prognosis by reducing compliance to medical treatments. Therefore, CNS is a key therapeutic target in DM1. Deeper knowledge of DM1 pathogenesis is prompting development of potential disease-modifying therapies: as DM1 is a rare, multisystem and slowly progressive disease, there is need of sensitive, tissue-specific prognostic and monitoring biomarkers in view of forthcoming clinical trials. Circulating Neurofilament light chain (NfL) levels have been recognized as a sensitive prognostic and monitoring biomarker of neuroaxonal damage in various CNS disorders. Methods We performed a cross-sectional study in a cohort of 40 adult DM1 patients, testing if serum NfL might be a potential biomarker of CNS involvement also in DM1. Moreover, we collected cognitive data, brain MRI, and other DM1-related diagnostic findings for correlation studies. Results Mean serum NfL levels resulted significantly higher in DM1 (25.32 +/- 28.12 pg/ml) vs 22 age-matched healthy controls (6.235 +/- 0.4809 pg/ml). Their levels positively correlated with age, and with one cognitive test (Rey's Auditory Verbal learning task). No correlations were found either with other cognitive data, or diagnostic parameters in the DM1 cohort. Conclusions Our findings support serum NfL as a potential biomarker of CNS damage in DM1, which deserves further evaluation on larger cross-sectional and longitudinal studies to test its ability in assessing brain disease severity and/or progression
The Life Span Determinant p66Shc Localizes to Mitochondria Where It Associates with Mitochondrial Heat Shock Protein 70 and Regulates Trans-membrane Potential
P66Shc regulates life span in mammals and is a critical component of the apoptotic response to oxidative stress. It functions as a downstream target of the tumor suppressor p53 and is indispensable for the ability of oxidative stress-activated p53 to induce apoptosis. The molecular mechanisms underlying the apoptogenic effect of p66Shc are unknown. Here we report the following three findings. (i) The apoptosome can be properly activated in vitro in the absence of p66Shc only if purified cytochrome c is supplied. (ii) Cytochrome c release after oxidative signals is impaired in the absence of p66Shc. (iii) p66Shc induces the collapse of the mitochondrial trans-membrane potential after oxidative stress. Furthermore, we showed that a fraction of cytosolic p66Shc localizes within mitochondria where it forms a complex with mitochondrial Hsp70. Treatment of cells with ultraviolet radiation induced the dissociation of this complex and the release of monomeric p66Shc. We propose that p66Shc regulates the mitochondrial pathway of apoptosis by inducing mitochondrial damage after dissociation from an inhibitory protein complex. Genetic and biochemical evidence suggests that mitochondria regulate life span through their effects on the energetic metabolism (mitochondrial theory of aging). Our data suggest that mitochondrial regulation of apoptosis might also contribute to life span determination
AUTONOMOUS SYSTEMS & SAFETY ISSUES: THE ROADMAP TO ENABLE NEW ADVANCES IN INDUSTRIAL APPLICATIONS
The paper addresses the safety issues related to the development of new solutions based on autonomous systems for industrial applications and the necessity to develop experimental environments for investigating these cases; a set of examples is proposed in order to provide cases and challenges as well as to suggest approaches to address these problems
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