1,655 research outputs found
Nonparametric circular quantile regression
We discuss nonparametric estimation of conditional quantiles of a circular distribution when the conditioning variable is either linear or circular. Two different approaches are pursued: inversion of a conditional distribution function estimator, and minimization of a smoothed check function. Local constant and local linear versions of both estimators are discussed. Simulation experiments and a real data case study are used to illustrate the usefulness of the methods
'Post-genomic era sheds light on Goethe’s Palm origins (Chamaerops humilis L.)
openThe increasing development of the post-genomic era is becoming more and more reliable among the scientific research field. In particular, reference genomes are acquiring great importance for the conservation of biodiversity. In this regard, one of the aims of this study was to obtain a first draft genome of the non-model palm species Chamaerops humilis L. Pursuing this goal drove our research to better understanding the origin of the C. humilis specimen present in the Botanical Garden of Padua. This last aspect has been of great importance due to the great cultural and historical significance of this individual, better known as the Goethe’s palm. Our results provided us with a fragmented but quite complete genome; moreover, it helped us to understand that Goethe’s palm belongs to the western part of the C. humilis clusters found among the Mediterranean Basin. In particular, we relied on the information provided by ten microsatellites found across the genome. These have been merged and compared to the Giovino’s et al. 2023 dataset. From now on, we only have to wait to see what future studies will reserve for us.The increasing development of the post-genomic era is becoming more and more reliable among the scientific research field. In particular, reference genomes are acquiring great importance for the conservation of biodiversity. In this regard, one of the aims of this study was to obtain a first draft genome of the non-model palm species Chamaerops humilis L. Pursuing this goal drove our research to better understanding the origin of the C. humilis specimen present in the Botanical Garden of Padua. This last aspect has been of great importance due to the great cultural and historical significance of this individual, better known as the Goethe’s palm. Our results provided us with a fragmented but quite complete genome; moreover, it helped us to understand that Goethe’s palm belongs to the western part of the C. humilis clusters found among the Mediterranean Basin. In particular, we relied on the information provided by ten microsatellites found across the genome. These have been merged and compared to the Giovino’s et al. 2023 dataset. From now on, we only have to wait to see what future studies will reserve for us
An Overview of Forest Cover and Management in Italy
Over the centuries, alongside multiple changes in socio-economical conditions, needs and technical possibilities, Italian forest and forest management have gone through a dynamic and complex evolution process. In the last decade, forest lands in Italy have been constantly growing and nowadays cover almost 11 million hectars, accounting for 36.4 % of the total national territory. Several quantitative and qualitative aspects of forest resources, regarding species composition, actual and available stock, ownership, volume of utilization, accessibility, terrain features and others, have been described through the analysis of the National Forest Inventory (INFC2005). The most represented forest typology is »coppice with standards«, while many forests are in a mature stage, waiting for conversion to transitional stands. Concerning forest logging, full length harvesting and winching-skidding extraction are the most widespread systems, but in many areas the low-openness conditions represent a limiting factor for logging distances, expecially in high slope classes, where sustainable and cost-effective operations are primary. The modern solutions allowed by technological progress, in addition to the growing environmental awareness and need of a sustainable management at multiple level, require an effi cient forest communication management and professional training of operators, in a challenging scenario that Italy is called to approach
On boosting kernel regression
In this paper we propose a simple multistep regression smoother which is constructed in an iterative manner, by learning the Nadaraya-Watson estimator with L-2 boosting. We find, in both theoretical analysis and simulation experiments, that the bias converges exponentially fast. and the variance diverges exponentially slow. The first boosting step is analysed in more detail, giving asymptotic expressions as functions of the smoothing parameter, and relationships with previous work are explored. Practical performance is illustrated by both simulated and real data
Evidence from multivariate morphometric study of the quercus pubescens complex in southeast Italy
The name Quercus pubescens s.l. encompasses a complex of deciduous oak taxa with mainly southeastEuropean
distribution and a large ecological niche. As the easternmost region of Italy, Apulia is
rather isolated from a geographical and physiographical viewpoint and counts the highest number
of oak species (10). In the taxonomic and phytosociological literature, the occurrence of several
species belonging to the Quercus pubescens collective group is reported for this region. In order to
verify if different sets of morphological characters are associated with different taxa, 24 populations
of Quercus pubescens s.l. located in different ecological-geographical areas of Apulia were sampled.
A total of 367 trees, 4254 leaves and 1120 fruits were collected and morphologically analysed.
Overall, 25 morphological characters of oak leaves and fruits were statistically treated using both
univariate and multivariate analysis. Nested ANOVA showed that leaves collected from a single tree
exhibited a degree of morphological variability higher than that observed when comparing leaves
coming from different trees of the same population and from different trees of different populations
as well. Almost all the morphological characters analysed exhibited a continuous trend of variation
so that none of them can be used as a character to discriminate between populations. Only leaf
and fruit “size” and fruit petiole length emerged as slightly discriminating characters. Our results
suggest that it is unlikely that more than one species belonging to the Quercus pubescens complex
occurs in the Apulia region. Comparison between the Apulian populations and a genetically
pure Q. pubescens population coming from a different area (the Molise region) strengthened the
assumption as to the existence of a single species that can provisionally be classified under the name
of Q. pubescens s.
Drug delivery in overcoming the blood-brain barrier: role of nasal mucosal grafting
The blood–brain barrier (BBB) plays a fundamental role in protecting and maintaining the homeostasis of the brain. For this reason, drug delivery to the brain is much more difficult than that to other compartments of the body. In order to bypass or cross the BBB, many strategies have been developed: invasive techniques, such as temporary disruption of the BBB or direct intraventricular and intracerebral administration of the drug, as well as noninvasive techniques. Preliminary results, reported in the large number of studies on the potential strategies for brain delivery, are encouraging, but it is far too early to draw any conclusion about the actual use of these therapeutic approaches. Among the most recent, but still pioneering, approaches related to the nasal mucosa properties, the permeabilization of the BBB via nasal mucosal engrafting can offer new potential opportunities. It should be emphasized that this surgical procedure is quite invasive, but the implication for patient outcome needs to be compared to the gold standard of direct intracranial injection, and evaluated whilst keeping in mind that central nervous system diseases and lysosomal storage diseases are chronic and severely debilitating and that up to now no therapy seems to be completely successful
- …