Search results for "54"
showing 10 items of 2200 documents
Interface Amorphization of Two‐Dimensional Black Phosphorus upon Treatment with Diazonium Salts
2021
Abstract Two‐dimensional (2D) black phosphorus (BP) represents one of the most appealing 2D materials due to its electronic, optical, and chemical properties. Many strategies have been pursued to face its environmental instability, covalent functionalization being one of the most promising. However, the extremely low functionalization degrees and the limitations in proving the nature of the covalent functionalization still represent challenges in many of these sheet architectures reported to date. Here we shine light on the structural evolution of 2D‐BP upon the addition of electrophilic diazonium salts. We demonstrated the absence of covalent functionalization in both the neutral and the r…
Impact of the Hypoechogenicity Criteria on Thyroid Nodule Malignancy Risk Stratification Performance by Different TIRADS Systems
2021
Background: Various Thyroid Imaging and Reporting data systems (TIRADS) are used worldwide for risk stratification of thyroid nodules. Their sensitivity is high, while the specificity is suboptimal. The aim of the study was to compare several TIRADS systems and evaluate the effect of hypoechogenicity as a sign of risk of malignancy on the overall assessment of diagnostic accuracy. Methods: The prospective study includes 274 patients with 289 thyroid nodules to whom US and risk of malignancy were assessed according to four TIRADS systems—European (EU-TIRADS), Korean (K-TIRADS), TIRADS by American College of Radiology (ACR TIRADS), and modified Kwak et al. TIRADS (L-TIRADS) systems, in which …
Performance of Contrast-Enhanced Ultrasound in Thyroid Nodules: Review of Current State and Future Perspectives
2021
Simple Summary Ultrasound has been used as baseline imaging for thyroid nodules for decades; nevertheless, no single feature is sensitive or specific enough to exclude or confirm thyroid malignancy. Therefore, clinical practice and research still focus on less invasive diagnostic patterns to reduce unnecessary fine-needle aspiration biopsies or surgery. The main advantage of CEUS is the ability to assess the sequence and intensity of vascular perfusion and hemodynamics in the thyroid nodule, thus providing real-time characterization of nodule features, and considered a valuable new approach in the determination of benign vs. malignant nodules. In addition, contrast agents used in CEUS can h…
Real-time observation of a correlation-driven sub 3 fs charge migration in ionised adenine
2021
Sudden ionisation of a relatively large molecule can initiate a correlation-driven process dubbed charge migration, where the electron density distribution is expected to rapidly move along the molecular backbone. Capturing this few-femtosecond or attosecond charge redistribution would represent the real-time observation of electron correlation in a molecule with the enticing prospect of following the energy flow from a single excited electron to the other coupled electrons in the system. Here, we report a time-resolved study of the correlation-driven charge migration process occurring in the nucleic-acid base adenine after ionisation with a 15–35 eV attosecond pulse. We find that the produ…
Investigation of Tinnitus Patients in Italy: Clinical and Audiological Characteristics
2010
Objective. 312 tinnitus sufferers were studied in order to analyze: the clinical characteristics of tinnitus; the presence of tinnitus-age correlation and tinnitus-hearing loss correlation; the impact of tinnitus on subjects' life and where possible the etiological/predisposing factors of tinnitus.Results. There is a slight predominance of males. The highest percentage of tinnitus results in the decades 61–70. Of the tinnitus sufferers, 197 (63.14%) have a hearing deficit (light hearing loss in 37.18% of cases). The hearing impairment results of sensorineural type in 74.62% and limited to the high frequencies in 58.50%. The tinnitus is referred as unilateral in 59.93%, a pure tone in 66.99%…
Impacts of oak deforestation and rainfed cultivation on soil redistribution processes across hillslopes using 137Cs techniques
2021
Abstract Background As one of the main components of land-use change, deforestation is considered the greatest threat to global environmental diversity with possible irreversible environmental consequences. Specifically, one example could be the impacts of land-use changes from oak forests into agricultural ecosystems, which may have detrimental impacts on soil mobilization across hillslopes. However, to date, scarce studies are assessing these impacts at different slope positions and soil depths, shedding light on key geomorphological processes. Methods In this research, the Caesium-137 (137Cs) technique was applied to evaluate soil redistribution and soil erosion rates due to the effects …
Noetherian type in topological products
2010
The cardinal invariant "Noetherian type" of a topological space $X$ (Nt(X)) was introduced by Peregudov in 1997 to deal with base properties that were studied by the Russian School as early as 1976. We study its behavior in products and box-products of topological spaces. We prove in Section 2: 1) There are spaces $X$ and $Y$ such that $Nt(X \times Y) < \min\{Nt(X), Nt(Y)\}$. 2) In several classes of compact spaces, the Noetherian type is preserved by the operations of forming a square and of passing to a dense subspace. The Noetherian type of the Cantor Cube of weight $\aleph_\omega$ with the countable box topology, $(2^{\aleph_\omega})_\delta$, is shown in Section 3 to be closely related …
Habilidades matemáticas tempranas en niños chilenos con Trastorno del Desarrollo del Lenguaje: Un estudio comparativo
2021
En las últimas décadas se ha incrementado el interés de las investigaciones respecto a las dificultades académicas que presentan los niños con Trastorno del Desarrollo del Lenguaje (TDL). No obstante, su relación con las habilidades matemáticas es una de las menos estudiadas. El objetivo de este estudio consistió en determinar si existen diferencias relevantes entre las habilidades matemáticas tempranas de niños con TDL y con desarrollo típico (DT). Participaron 78 niños de 4 a 7 años 11 meses de edad, pertenecientes a colegios con programas de integración escolar de Santiago de Chile. Se conformó un grupo de 44 niños con TDL y un grupo de 34 con DT. Se establecieron comparaciones del rendi…
Pharmacologic Inhibition of ADAM10 Attenuates Brain Tissue Loss, Axonal Injury and Pro-inflammatory Gene Expression Following Traumatic Brain Injury …
2021
The α-secretase A disintegrin and metalloprotease 10 (ADAM10) regulates various physiological and pathophysiological processes. Despite its broad functional implications during development, plasticity, and disease, no pharmacological approaches to inhibit ADAM10 in acute brain injury have been reported. Here, we examined the effects of the ADAM10 inhibitor GI254023X on the neurological and histopathological outcome after experimental traumatic brain injury (TBI). C57BL/6N mice were subjected to the controlled cortical impact (CCI) model of TBI or sham procedure and received GI254023X or vehicle during the acute phase of injury (n = 40, 100 mg/kg, 25% DMSO, 0.1 M Na2CO3, intraperitoneal, 30 …
What is a tree in the Mediterranean Basin hotspot? A critical analysis
2019
Background: Tree species represent 20% of the vascular plant species worldwide and they play a crucial role in the global functioning of the biosphere. The Mediterranean Basin is one of the 36 world biodiversity hotspots, and it is estimated that forests covered 82% of the landscape before the first human impacts, thousands of years ago. However, the spatial distribution of the Mediterranean biodiversity is still imperfectly known, and a focus on tree species constitutes a key issue for understanding forest functioning and develop conservation strategies. Methods: We provide the first comprehensive checklist of all native tree taxa (species and subspecies) present in the Mediterranean-Europ…