Characterization and Mapping of Fuel Types for the Mediterranean Ecosystems of Pollino National Park in Southern Italy by Using Hyperspectral MIVIS Data

Abstract The characterization and mapping of fuel types is one of the most important factors that should be taken into consideration for wildland fire prevention and prefire planning. This research aims to investigate the usefulness of hyperspectral data to recognize and map fuel types in order to ascertain how well remote sensing data can provide an exhaustive classification of fuel properties. For this purpose airborne hyperspectral Multispectral Infrared and Visible Imaging Spectrometer (MIVIS) data acquired in November 1998 have been analyzed for a test area of 60 km2 selected inside Pollino National Park in the south of Italy. Fieldwork fuel-type recognitions, performed at the same time as remote sensing data acquisition, were used as a ground-truth dataset to assess the results obtained for the considered test area. The method comprised the following three steps: 1) adaptation of Prometheus fuel types for obtaining a standardization system useful for remotely sensed classification of fuel types and properties in the considered Mediterranean ecosystems; 2) model construction for the spectral characterization and mapping of fuel types based on a maximum likelihood (ML) classification algorithm; and 3) accuracy assessment for the performance evaluation based on the comparison of MIVIS-based results with ground truth. Results from our analysis showed that the use of remotely sensed data at high spatial and spectral resolution provided a valuable characterization and mapping of fuel types being that the achieved classification accuracy was higher than 90%

Cerebral Spectral Perturbation during Upper Limb Diagonal Movements

While it has been suggested that diagonal rhythmical bilateral movements promote improvement in motor and cognitive functions, no study that we are aware of has actually examined electrophysiological changes during diagonal movements. Therefore, we aimed to study cerebral activity during the performance of diagonal and vertical movements (DM and VM, respectively), through EEG recording focusing on theta, alpha, and beta frequency bands. Following independent component analysis, we computed time-frequency and source localization analysis. We found that (1) increased frontal theta during the initiation of DM was possibly related to the computational effort; (2) a biphasic pattern of frontoparietal alpha/beta modulations was found during VM; and in addition, (3) source localization showed increased frontal theta during DM generated in the middle frontal cortex. We will discuss the current results and their implications in relation to task difficulty, spatial and temporal computation

Optimal Spectral Domain Selection for Maximizing Archaeological Signatures: Italy Case Studies

Different landscape elements, including archaeological remains, can be automatically classified when their spectral characteristics are different, but major difficulties occur when extracting and classifying archaeological spectral features, as archaeological remains do not have unique shape or spectral characteristics. The spectral anomaly characteristics due to buried remains depend strongly on vegetation cover and/or soil types, which can make feature extraction more complicated. For crop areas, such as the test sites selected for this study, soil and moisture changes within near-surface archaeological deposits can influence surface vegetation patterns creating spectral anomalies of various kinds. In this context, this paper analyzes the usefulness of hyperspectral imagery, in the 0.4 to 12.8 μm spectral region, to identify the optimal spectral range for archaeological prospection as a function of the dominant land cover. MIVIS airborne hyperspectral imagery acquired in five different archaeological areas located in Italy has been used. Within these archaeological areas, 97 test sites with homogenous land cover and characterized by a statistically significant number of pixels related to the buried remains have been selected. The archaeological detection potential for all MIVIS bands has been assessed by applying a Separability Index on each spectral anomaly-background system of the test sites. A scatterplot analysis of the SI values vs. the dominant land cover fractional abundances, as retrieved by spectral mixture analysis, was performed to derive the optimal spectral ranges maximizing the archaeological detection. This work demonstrates that whenever we know the dominant land cover fractional abundances in archaeological sites, we can a priori select the optimal spectral range to improve the efficiency of archaeological observations performed by remote sensing data

A Scoping Review of Neuromodulation Techniques in Neurodegenerative Diseases: A Useful Tool for Clinical Practice?

Background and Objectives: Neurodegenerative diseases that typically affect the elderly such as Alzheimer’s disease, Parkinson’s disease and frontotemporal dementia are typically characterised by significant cognitive impairment that worsens significantly over time. To date, viable pharmacological options for the cognitive symptoms in these clinical conditions are lacking. In recent years, various studies have employed neuromodulation techniques to try and contrast patients’ decay. Materials and Methods: We conducted an in-depth literature review of the state-of-the-art of the contribution of these techniques across these neurodegenerative diseases. Results: The present review reports that neuromodulation techniques targeting cognitive impairment do not allow to draw yet any definitive conclusion about their clinical efficacy although preliminary evidence is very encouraging. Conclusions: Further and more robust studies should evaluate the potentialities and limitations of the application of these promising therapeutic tools to neurodegenerative diseases

A Scoping Review of Cognitive Training in Neurodegenerative Diseases via Computerized and Virtual Reality Tools: What We Know So Far

Most prevalent neurodegenerative diseases such as Alzheimer’s disease, frontotemporal dementia, Parkinson’s disease and multiple sclerosis are heterogeneous in their clinical profiles and underlying pathophysiology, although they typically share the presence of cognitive impairment that worsens significantly during the course of the disease. Viable pharmacological options for cognitive symptoms in these clinical conditions are currently lacking. In recent years, several studies have started to apply Computerized Cognitive Training (CCT) and Virtual Reality (VR) tools to try and contrast patients’ cognitive decay over time. However, no in-depth literature review of the contribution of these promising therapeutic options across main neurodegenerative diseases has been conducted yet. The present paper reports the state-of-the-art of CCT and VR studies targeting cognitive impairment in most common neurodegenerative conditions. Our twofold aim is to point out the scientific evidence available so far and to support health professionals to consider these promising therapeutic tools when planning rehabilitative interventions, especially when the access to regular and frequent hospital consultations is not easy to be provided

The hemispheric distribution of \u3b1-band EEG activity during orienting of attention in patients with reduced awareness of the left side of space (spatial neglect)

EEG studies in healthy humans have highlighted that alpha-band activity is relatively reduced over the occipital-parietal areas of the hemisphere contralateral to the direction of spatial attention. Here, we investigated the hemispheric distribution of alpha during orienting of attention in male and female right-brain-damaged patients with left spatial neglect. Temporal spectral evolution showed that in patients with neglect alpha oscillations over the damaged hemisphere were pathologically enhanced both during the baseline-fixation period that preceded cued orienting (capturing tonic alpha changes) and during orienting with leftward, rightward or neutral-bilateral spatial cues (reflecting phasic alpha changes). Patients without neglect showed a similar though significantly less enhanced hemispheric asymmetry. Healthy controls displayed a conventional decrease of alpha activity over the hemisphere contralateral to the direction of orienting. In right-brain-damaged patients, neglect severity in the line bisection task was significantly correlated both with tonic alpha asymmetry during the baseline period and with phasic asymmetries during orienting of attention with neutral-bilateral and leftward cues. Asymmetries with neutral-bilateral and leftward cues were correlated with lesion of white matter tracts linking frontal with parietal-occipital areas. These findings show that disruption of rostro-caudal white matter connectivity in the right hemisphere interferes with the maintenance of optimal baseline-tonic levels of alpha and the phasic modulation of alpha activity during shifts of attention. The hemispheric distribution of alpha activity can be used as a diagnostic tool for acquired pathological biases of spatial attention due to unilateral brain damage.SIGNIFICANCE STATEMENTAlpha desynchronization over the hemisphere contralateral to the attended side of space is a reliable marker of attentional orienting in the healthy human brain: can the same marker be used to spot and quantify acquired disturbances of spatial attention after unilateral brain injuries? Are pathological modifications in the hemispheric distribution of alpha specifically linked to attentional neglect for one side of space? We show that in patients with right brain damage the pathological enhancement of alpha oscillations over the parietal and occipital areas of the injured hemisphere is correlated with reduced awareness for the left side of space and with lesion of white matter pathways that subserve frontal modulation of alpha activity in posterior brain areas

Selective reorienting response of the left hemisphere to invalid visual targets in the right side of space: relevance for the spatial neglect syndrome

In humans, damage in the right hemisphere often provokes the striking inability to attend the left side of space, i.e. left spatial neglect. For years the leading hypothesis for the higher epidemiological incidence of left over right spatial neglect has been that the right hemisphere can orient attention to both sides of space while the left hemisphere only to the right side. Because of this hemispheric specialization, patients with lesion in the left hemisphere do not usually suffer right spatial neglect. Though comprehensive and very influential, to date, this explanation only found clear support in a MEG investigation into stimulus driven shifts of auditory attention. In contrast, no evidence for the same hypothesis was ever gathered from studies of visual attention run with behavioral paradigms that have importantly influenced the interpretation and modeling of attentional deficits in left spatial neglect. Here we report the first fMRI evidence directly supporting this long-standing hypothesis on the hemispheric lateralisation of mechanisms regulating orienting of spatial attention in the human brain. By demonstrating that the left hemisphere selectively reorients attention to invalidly cued visual targets in the right side of space we provide a more comprehensive account for deficits of spatial attention suffered by right brain damaged patients with left unilateral neglect

Reconstructing the origins of the space-number association: spatial and number-magnitude codes must be used jointly to elicit spatially organised mental number lines

In a series of five experiments with unimanual Go/No-Go tasks and intermixed Arabic numerical, i.e. numbers lower or higher than 5, and directional targets, i.e. arrows pointing to the left or to the right, we explored whether spatial codes used in isolation inherently evoke the left-to-right representation of number magnitudes, i.e. Space-to-Number congruency effect, and, vice-versa, whether number-magnitude codes used in isolation inherently evoke the conceptual activation of left/right spatial codes, i.e. Number-to-Space congruency effect. In Experiment 1 Go responses were provided based on instructions that activated only magnitude codes, e.g. "push only if the number is lower than 5 and whenever an arrow appears", or only spatial codes, e.g. "push only when an arrow points to the left and whenever a number appears". In Experiments 2-4, the same instructions were combined with the request of responding only to arrows in a specific colour. No fixed association was present between a specific arrow colour and a specific arrow direction. In Experiment 3, the direction of arrow-targets was kept fixed to favour the processing of arrow direction. In Experiment 4, an additional class of No-Go visual stimuli was included to heighten the focus of attention on numerical and directional arrow-targets and, in addition, only numbers 1, 2, 8 and 9 were used to force the contrast between small and large magnitude codes. The results of Experiments 1-4 highlighted no significant or reliable Space-to-Number congruency effect, e.g. faster RTs to numbers lower than 5 when participants attend to arrows pointing to the left, or Number-to-Space congruency effect, e.g. faster RTs to arrows pointing to the left when participants attend to numbers lower than 5. In Experiment 5 we confirmed that when spatial and number magnitude codes are used in conjunction, e.g. " push only when an arrow points left and when a number is lower than 5", a significant Space-to-Number congruency effect is found and we expanded this evidence to Number-to-Space congruency. Split-half testing showed that in Experiment 5 congruency effects were reliable and null-hypothesis significance testing showed that they were different from those found in all other experiments. We conclude that neither space codes used in isolation can elicit a spatial representation of number magnitudes nor number-magnitude codes used in isolation can trigger the activation of spatial codes. Thus, spatial and numerical codes must be used jointly to evoke reliable spatially organised mental number lines