194 research outputs found
Removal of electrostatic artifacts in magnetic force microscopy by controlled magnetization of the tip: application to superparamagnetic nanoparticles
Magnetic force microscopy (MFM) has been demonstrated as valuable technique for the
characterization of magnetic nanomaterials. To be analyzed by MFM techniques, nanomaterials
are generally deposited on flat substrates, resulting in an additional contrast in MFM images due to
unavoidable heterogeneous electrostatic tip-sample interactions, which cannot be easily distinguished
from the magnetic one. In order to correctly interpret MFM data, a method to remove the electrostatic
contributions from MFM images is needed. In this work, we propose a new MFM technique, called
controlled magnetization MFM (CM-MFM), based on the in situ control of the probe magnetization
state, which allows the evaluation and the elimination of electrostatic contribution in MFM images. The
effectiveness of the technique is demonstrated through a challenging case study, i.e., the analysis of
superparamagnetic nanoparticles in absence of applied external magnetic field. Our CM-MFM technique
allowed us to acquire magnetic images depurated of the electrostatic contributions, which revealed
that the magnetic field generated by the tip is sufficient to completely orient the superparamagnetic
nanoparticles and that the magnetic tip-sample interaction is describable through simple models once
the electrostatic artifacts are removed
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Predicting Empathy From Resting State Brain Connectivity: A Multivariate Approach.
Recent task fMRI studies suggest that individual differences in trait empathy and empathic concern are mediated by patterns of connectivity between self-other resonance and top-down control networks that are stable across task demands. An untested implication of this hypothesis is that these stable patterns of connectivity should be visible even in the absence of empathy tasks. Using machine learning, we demonstrate that patterns of resting state fMRI connectivity (i.e. the degree of synchronous BOLD activity across multiple cortical areas in the absence of explicit task demands) of resonance and control networks predict trait empathic concern (n = 58). Empathic concern was also predicted by connectivity patterns within the somatomotor network. These findings further support the role of resonance-control network interactions and of somatomotor function in our vicariously driven concern for others. Furthermore, a practical implication of these results is that it is possible to assess empathic predispositions in individuals without needing to perform conventional empathy assessments
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Mechanisms of cognitive-behavioral therapy for obsessive-compulsive disorder involve robust and extensive increases in brain network connectivity.
Cognitive-behavioral therapy (CBT) is effective for obsessive compulsive disorder (OCD); however, little is understood about its mechanisms related to brain network connectivity. We examined connectivity changes from resting-state functional magnetic resonance imaging data pre-to-post-CBT in 43 OCD participants, randomized to receive either 4 weeks of intensive CBT or 4 weeks waitlist followed by 4 weeks of CBT, and 24 healthy controls before and after 4 weeks of no treatment. Network-based-statistic analysis revealed large-magnitude increases in OCD connectivity in eight networks. Strongest increases involved connectivity between the cerebellum and caudate/putamen, and between the cerebellum and dorsolateral/ventrolateral prefrontal cortices. Connectivity increases were associated with increased resistance to compulsions. Mechanisms of CBT may involve enhanced cross-network integration, both within and outside of classical cortico-striatal-thalamo-cortical regions; those involving cerebellar to striatal and prefrontal regions may reflect acquisition of new non-compulsive goal-directed behaviors and thought patterns. Our findings have implications for identifying targets for enhancing treatment efficacy and monitoring treatment progress
The differences between classical and modern tale
Tutti conoscono la parola fiaba, ognuno però la collega a cose diverse. La fiaba è un racconto, una novella con elementi magici al suo interno. Troviamo diverse tipologie di fiaba. Nella tesi vengono trattate, discusse e messe a confronto la fiaba classica e la fiaba moderna. In primo luogo si è cercato di esplicare le caratteristiche della fiaba in generale volgendo una particolare attenzione all’analisi delle differenze tra le fiabe classica e moderna tenendo conto anche delle funzioni di Vladimir Propp. Nel lavoro abbiamo analizzato le fiabe classiche e le fiabe moderne più famose ed i loro autori ed esposto le differenze tra gli autori della stessa tipologia di fiaba e infine tra le due tipologie di fiabe. Abbiamo menzionato la “nuova” versione delle fiabe, quella introdotta da Walt Disney, e il nuovo genere creato dalla fiaba, il fantasy. È stato trattato l’argomento “la letteratura per l’infanzia” e cercato di capire quale sia il pubblico più adatto per questo genere letterario. Infine sono state analizzate e discusse le funzioni educative delle fiabe moderna e classica, si è cercato di capire quale fiaba sia più giusta e adatta ai bambini e perché e di esporre i criteri in base ai quali dovrebbe venir effettuata la scelta delle educatrici sulla fiaba da introdurre nella scuola per l’infanzia come pure l’importanza della fiaba stessa nella scuola dell’infanzia. Infine è stato esposto e commentato il fatto di mostrare le immagini durante la lettura delle fiabe riportando diverse teorie che dimostrano come le immagini possono essere positive e negative nelle fiabe. Si è cercato dunque di capire l’importanza o meno dell’uso delle immagini nel raccontare una fiaba. In conclusione è stata svolta una ricerca empirica per somministrazione di un questionario da compilare dalle educatrici delle scuole per l’infanzia in Istria su quali fiabe preferiscono leggere ai bambini, quanto leggono le fiabe, se preferiscono leggere le fiabe classiche o moderne e perché e la scelta delle fiabe.Svi poznaju riječ bajka, ali ju povezuju s različitim stvarima. Bajka je priča, pripovijetka s ugrađenim čarobnim elementima. Nalazimo različite vrste bajki. U radu se raspravlja o sličnostima i razlikama između klasične i moderne bajke. Prvo se pokušalo navesti karakteristike bajke uopće pridajući posebnu pozornost analizi razlika između klasične i moderne bajke, uzimajući u obzir i funkcije Vladimira Proppa. U radu je prikazan presjek najpoznatijih klasičnih i modernih bajki i njihovih autora, izložene su razlike između autora istog tipa bajke te između dviju vrsti bajki. Spomenuli smo „novu” verziju bajke, koju je uveo Walt Disney i novostvoreni žanr koji je proizašao iz bajke, fantasy roman. Raspravljalo se o dječjoj književnosti te se nastojalo razumjeti koja je najprikladnija publika za ovaj književni žanr. Potom su se analizirale obrazovne funkcije klasične i moderne bajke, pokušalo se shvatiti koji je tip bajke prikladniji za rad s djecom u predškolskim ustanovama i zašto te odrediti kriterije prema kojima bi odgojitelji trebali obaviti odabir bajke, kao i važnost same bajke u predškolskoj ustanovi. Na kraju teorijskog dijela raspravljalo se o potrebi pokazivanja slika dok se čita bajka te su iznijete različite teorije na tu temu koje pokazuju kako slike mogu imati pozitivni i negativni učinak. Slijedom toga pokušalo se shvatiti je li korištenje slika pri pripovijedanju bajke važno ili nije. U zadnjem dijelu prikazani su rezultati empirijskog istraživanja, provedenog putem upitnika koji su popunjavali odgajatelji vrtića u Istri. Istražili smo koje bajke odgojitelji vole čitati djeci, koliko čitaju bajke djeci, jesi li im draže klasične ili moderne bajke i zašto te njihov stav o izboru bajki.Everybody is familiar with the word fairy tale, but they link it to different things. A fairy tale is a story, a narrative which has elements of magic built in it. There are various types of fairy tales. This paper discusses the similarities and differences between the classic and modern fairy tale. First, it attempts to list the general characteristics of fairy tales, paying special attention to the analysis of differences between the classic and modern fairy tale, also consideringthe functions given by Vladimir Propp. The paper also offers an overview of the most popular classic and modern fairy tales and their authors, so the differences between authors of the same type of fairy tales, as well as between two types of fairy tales, are presented. The “new” version of fairy tales introduced by Walt Disney is mentioned, along with the newly composed genre which has arisen from fairy tales, the fantasy novel. Children’s literature is also discussed with the intention to understand which public is the most appropriate for this literary genre. Secondly, the educational functions of the classic and modern fairy tale are analysed. The aim is to understand which type of fairy tale is the most appropriate in working with children in preschool institutions and why, but also to set the criteria according to which preschool teachers should choose fairy tales. The sole importance of fairy tales in preschool institutions is also discussed. At the end of the theoretical part there is a discussion about the need to show pictures while reading fairy tales. Various theories about this topic are presented, and they show that pictures can have both a positive and negative effect. The intention is to understand if using pictures in story-telling is important or not. The last part of the paper displays results of an empirical research conducted through a questionnaire and filled out by Istrian kindergartens’ educators. They answered about which fairy tales they liked to read to their children, how oftent hey read fairy tales to children, if they liked classic or modern fairy tales more and why, an
The differences between classical and modern tale
Tutti conoscono la parola fiaba, ognuno però la collega a cose diverse. La fiaba è un racconto, una novella con elementi magici al suo interno. Troviamo diverse tipologie di fiaba. Nella tesi vengono trattate, discusse e messe a confronto la fiaba classica e la fiaba moderna. In primo luogo si è cercato di esplicare le caratteristiche della fiaba in generale volgendo una particolare attenzione all’analisi delle differenze tra le fiabe classica e moderna tenendo conto anche delle funzioni di Vladimir Propp. Nel lavoro abbiamo analizzato le fiabe classiche e le fiabe moderne più famose ed i loro autori ed esposto le differenze tra gli autori della stessa tipologia di fiaba e infine tra le due tipologie di fiabe. Abbiamo menzionato la “nuova” versione delle fiabe, quella introdotta da Walt Disney, e il nuovo genere creato dalla fiaba, il fantasy. È stato trattato l’argomento “la letteratura per l’infanzia” e cercato di capire quale sia il pubblico più adatto per questo genere letterario. Infine sono state analizzate e discusse le funzioni educative delle fiabe moderna e classica, si è cercato di capire quale fiaba sia più giusta e adatta ai bambini e perché e di esporre i criteri in base ai quali dovrebbe venir effettuata la scelta delle educatrici sulla fiaba da introdurre nella scuola per l’infanzia come pure l’importanza della fiaba stessa nella scuola dell’infanzia. Infine è stato esposto e commentato il fatto di mostrare le immagini durante la lettura delle fiabe riportando diverse teorie che dimostrano come le immagini possono essere positive e negative nelle fiabe. Si è cercato dunque di capire l’importanza o meno dell’uso delle immagini nel raccontare una fiaba. In conclusione è stata svolta una ricerca empirica per somministrazione di un questionario da compilare dalle educatrici delle scuole per l’infanzia in Istria su quali fiabe preferiscono leggere ai bambini, quanto leggono le fiabe, se preferiscono leggere le fiabe classiche o moderne e perché e la scelta delle fiabe.Svi poznaju riječ bajka, ali ju povezuju s različitim stvarima. Bajka je priča, pripovijetka s ugrađenim čarobnim elementima. Nalazimo različite vrste bajki. U radu se raspravlja o sličnostima i razlikama između klasične i moderne bajke. Prvo se pokušalo navesti karakteristike bajke uopće pridajući posebnu pozornost analizi razlika između klasične i moderne bajke, uzimajući u obzir i funkcije Vladimira Proppa. U radu je prikazan presjek najpoznatijih klasičnih i modernih bajki i njihovih autora, izložene su razlike između autora istog tipa bajke te između dviju vrsti bajki. Spomenuli smo „novu” verziju bajke, koju je uveo Walt Disney i novostvoreni žanr koji je proizašao iz bajke, fantasy roman. Raspravljalo se o dječjoj književnosti te se nastojalo razumjeti koja je najprikladnija publika za ovaj književni žanr. Potom su se analizirale obrazovne funkcije klasične i moderne bajke, pokušalo se shvatiti koji je tip bajke prikladniji za rad s djecom u predškolskim ustanovama i zašto te odrediti kriterije prema kojima bi odgojitelji trebali obaviti odabir bajke, kao i važnost same bajke u predškolskoj ustanovi. Na kraju teorijskog dijela raspravljalo se o potrebi pokazivanja slika dok se čita bajka te su iznijete različite teorije na tu temu koje pokazuju kako slike mogu imati pozitivni i negativni učinak. Slijedom toga pokušalo se shvatiti je li korištenje slika pri pripovijedanju bajke važno ili nije. U zadnjem dijelu prikazani su rezultati empirijskog istraživanja, provedenog putem upitnika koji su popunjavali odgajatelji vrtića u Istri. Istražili smo koje bajke odgojitelji vole čitati djeci, koliko čitaju bajke djeci, jesi li im draže klasične ili moderne bajke i zašto te njihov stav o izboru bajki.Everybody is familiar with the word fairy tale, but they link it to different things. A fairy tale is a story, a narrative which has elements of magic built in it. There are various types of fairy tales. This paper discusses the similarities and differences between the classic and modern fairy tale. First, it attempts to list the general characteristics of fairy tales, paying special attention to the analysis of differences between the classic and modern fairy tale, also consideringthe functions given by Vladimir Propp. The paper also offers an overview of the most popular classic and modern fairy tales and their authors, so the differences between authors of the same type of fairy tales, as well as between two types of fairy tales, are presented. The “new” version of fairy tales introduced by Walt Disney is mentioned, along with the newly composed genre which has arisen from fairy tales, the fantasy novel. Children’s literature is also discussed with the intention to understand which public is the most appropriate for this literary genre. Secondly, the educational functions of the classic and modern fairy tale are analysed. The aim is to understand which type of fairy tale is the most appropriate in working with children in preschool institutions and why, but also to set the criteria according to which preschool teachers should choose fairy tales. The sole importance of fairy tales in preschool institutions is also discussed. At the end of the theoretical part there is a discussion about the need to show pictures while reading fairy tales. Various theories about this topic are presented, and they show that pictures can have both a positive and negative effect. The intention is to understand if using pictures in story-telling is important or not. The last part of the paper displays results of an empirical research conducted through a questionnaire and filled out by Istrian kindergartens’ educators. They answered about which fairy tales they liked to read to their children, how oftent hey read fairy tales to children, if they liked classic or modern fairy tales more and why, an
Microscopies at the nanoscale for nano-scale drug delivery systems
One of the frontier of nanoscience is undoubtedly represented by the use of nanotechnologies
in the pharmaceutical research. During the last decades a big family of nanostructures that have a
surface-acting action, such as NanoParticles (NPs), lipid nanocarriers and many more, have been developed
to be used as Drug Delivery Systems (DDSs). However, these nanocarriers opened also new
frontiers in nanometrology, requiring an accurate morphological characterization, near atomic resolution,
before they are really available to clinicians to ascertain their elemental composition, to exclude the presence of contaminants
introduced during the synthesis procedure and to ensure biocompatibility. Classical Transmission (TEM) and
Scanning Electron Microscopy (SEM) techniques frequently have to be adapted for an accurate analysis of formulation
morphology, especially in case of hydrated colloidal systems. Specific techniques such as environmental scanning microscopy
and/or cryo preparation are required for their investigation. Analytical Electron Microscopy (AEM) techniques such
as Electron Energy-Loss Spectroscopy (EELS) or Energy-Dispersive X-ray Spectroscopy (EDXS) are additional assets to
determine the elemental composition of the systems. Here we will discuss the importance of Electron Microscopy (EM) as
a reliable tool in the pharmaceutical research of the 21st century, focalizing our attention on advantages and limitations of
different kind of NPs (in particular silver and carbon NPs, cubosomes) and vesicles (liposomes and niosomes)
Disentangling disorders of consciousness: Insights from diffusion tensor imaging and machine learning
Previous studies have suggested that disorders of consciousness (DOC) after severe brain injury may result from disconnections of the thalamo-cortical system. However, thalamo-cortical connectivity differences between vegetative state (VS), minimally conscious state minus (MCS−, i.e., low-level behavior such as visual pursuit), and minimally conscious state plus (MCS+, i.e., high-level behavior such as language processing) remain unclear. Probabilistic tractography in a sample of 25 DOC patients was employed to assess whether structural connectivity in various thalamo-cortical circuits could differentiate between VS, MCS−, and MCS+ patients. First, the thalamus was individually segmented into seven clusters based on patterns of cortical connectivity and tested for univariate differences across groups. Second, reconstructed whole-brain thalamic tracks were used as features in a multivariate searchlight analysis to identify regions along the tracks that were most informative in distinguishing among groups. At the univariate level, it was found that VS patients displayed reduced connectivity in most thalamo-cortical circuits of interest, including frontal, temporal, and sensorimotor connections, as compared with MCS+, but showed more pulvinar-occipital connections when compared with MCS−. Moreover, MCS− exhibited significantly less thalamo-premotor and thalamo-temporal connectivity than MCS+. At the multivariate level, it was found that thalamic tracks reaching frontal, parietal, and sensorimotor regions, could discriminate, up to 100% accuracy, across each pairwise group comparison. Together, these findings highlight the role of thalamo-cortical connections in patients\u27 behavioral profile and level of consciousness. Diffusion tensor imaging combined with machine learning algorithms could thus potentially facilitate diagnostic distinctions in DOC and shed light on the neural correlates of consciousness. Hum Brain Mapp 38:431–443, 2017. © 2016 Wiley Periodicals, Inc
An open platform for Aerosol InfraRed Spectroscopy analysis – AIRSpec
AIRSpec is a platform consisting of several chemometric packages developed
for analysis of Fourier transform infrared (FTIR) spectra of atmospheric
aerosols. The packages are accessible through a browser-based interface,
which also generates the necessary input files based on user interactions for
provenance management and subsequent use with a command-line interface. The
current implementation includes the task of baseline correction, organic
functional group (FG) analysis, and multivariate calibration for any analyte
with absorption in the mid-infrared. The baseline correction package uses
smoothing splines to correct the drift of the baseline of ambient aerosol
spectra given the variability in both environmental mixture composition and
substrates. The FG analysis is performed by fitting individual Gaussian line
shapes for alcohol (aCOH), carboxylic acid (COOH), alkane (aCH), carbonyl (CO),
primary amine (aNH2), and ammonium (ammNH) for each spectrum.
The multivariate calibration model uses the
spectra to estimate the concentration of relevant target variables (e.g.,
organic or elemental carbon) measured with different reference instruments.
In each of these analyses, AIRSpec receives spectra and user choices on
parameters for model computation; input files with parameters that can later
be used with a command-line interface for batch computation are returned
together with diagnostic figures and tables in text format. AIRSpec is built
using the open-source software consisting of R and Shiny and is released
under the GNU Public License v3. Users can download, modify, and extend the
package, or access its functionality through the web application
(http://airspec.epfl.ch, last access: 3 April 2019) hosted at the École polytechnique
fédérale de Lausanne (EPFL). AIRSpec provides a unified framework by
which different chemometric techniques can be shared and accessed, and its
underlying suite of packages provides the basic functionality for extending
the platform with new types of analyses. For example, basic functionality
includes operations for populating and accessing spectra residing in
in-memory arrays or relational databases, input and output of spectra and
results of computation, and user interface development. Moreover, AIRSpec
facilitates the exploratory work, can be used by FTIR spectra acquired with
different methods, and can be extended easily with new chemometric packages
when they become available. Therefore AIRSpec provides a framework for
centralizing and disseminating such algorithms. This paper describes the
modular architecture and provides examples of the implemented packages using
the spectra of aerosol samples collected on PM2.5 polytetrafluoroethylene (Teflon) filters.</p
Estimation of Organic and Elemental Carbon using FT-IR absorbance spectra from PTFE Filters
Organic carbon and elemental carbon are major components of atmospheric PM. Typically they are measured using destructive and relatively expensive methods (e.g., TOR). We aim to reduce the operating costs of large air quality monitoring networks using FT-IR spectra of ambient PTFE filters and PLS regression. We achieve accurate predictions for models (calibrated in 2011) that use samples collected at the same or different sites of the calibration data set and in a different year (2013)
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