246 research outputs found
Language re-discovered: A death education intervention in the net between kindergarten, family and territory
The article presents the positive results of a death education experience, realized owing to a collaboration between school, family and territory. The project, with the scope of reflecting on topics of death and spirituality, included 46 children of 5 from kindergarten and 50 parents, and then mobilizing the entire community. Social services and public administration had a special role in this, aiming to guarantee the necessary support for the families in the existential reflections. The experience was monitored with participatory observation, via interviews and questionnaires. The children answered questions regarding death and spirituality during an open and sincere conversation with the teachers. The parents, who at home talked about certain pre-defined teams with the children, were asked to give their informed consent and were given a questionnaire with open questions ex-ante/ ex-post. All data were processed via qualitative analysis of the texts. The results are truly positive, showing that children are capable of facing the problem of death and are able to acquire a certain representation of the spiritual dimension. The parents, who in the beginning demonstrated some anxiety, eventually were greatly satisfied and expressed their willingness to continue to search for the connection between death and transcendence
Interplay between static and dynamic polar correlations in relaxor Pb(Mg_{1/3}Nb_{2/3})O_{3}
We have characterized the dynamics of the polar nanoregions in
Pb(MgNb)O (PMN) through high-resolution neutron
backscattering and spin-echo measurements of the diffuse scattering cross
section. We find that the diffuse scattering intensity consists of \emph{both}
static and dynamic components. The static component first appears at the Curie
temperature K, while the dynamic component freezes completely
at the temperature T K; together, these components account for
all of the observed spectral weight contributing to the diffuse scattering
cross section. The integrated intensity of the dynamic component peaks near the
temperature at which the frequency-dependent dielectric constant reaches a
maximum (T) when measured at 1 GHz, i. e. on a timescale of
ns. Our neutron scattering results can thus be directly related to dielectric
and infra-red measurements of the polar nanoregions. Finally, the global
temperature dependence of the diffuse scattering can be understood in terms of
just two temperature scales, which is consistent with random field models.Comment: (8 pages, 5 figures, submitted to Phys. Rev. B
Solid Surface Structure Affects Liquid Order at the Polystyrene/SAM Interface
We present a combined x-ray and neutron reflectivity study characterizing the
interface between polystyrene (PS) and silanized surfaces. Motivated by the
large difference in slip velocity of PS on top of dodecyl-trichlorosilane (DTS)
and octadecyl-trichlorosilane (OTS) found in previous studies, these two
systems were chosen for the present investigation. The results reveal the
molecular conformation of PS on silanized silicon. Differences in the molecular
tilt of OTS and DTS are replicated by the adjacent phenyl rings of the PS. We
discuss our findings in terms of a potential link between the microscopic
interfacial structure and dynamic properties of polymeric liquids at
interfaces
Speckle observations of the binary asteroid (22) Kalliope with C2PU/PISCO
We present new speckle measurements of the position of Linus, the satellite
of the asteroid (22) Kalliope, obtained at the 1m C2PU-Epsilon telescope on the
Plateau de Calern, France. Observations were made in the visible domain with
the speckle camera PISCO. We obtained 122 measurements in February-March 2022
and April 2023, with a mean uncertainty close to 10 milli-arcseconds on the
angular separation
Temperature-dependent structure and dynamics of highly-branched poly(N-isopropylacrylamide) in aqueous solution
Small-angle neutron scattering (SANS) and neutron spin-echo (NSE) have been used to investigate the temperature-dependent solution behaviour of highly-branched poly(N-isopropylacrylamide) (HB-PNIPAM). SANS experiments have shown that water is a good solvent for both HB-PNIPAM and a linear PNIPAM control at low temperatures where the small angle scattering is described by a single correlation length model. Increasing the temperature leads to a gradual collapse of HB-PNIPAM until above the lower critical solution temperature (LCST), at which point aggregation occurs, forming disperse spherical particles of up to 60 nm in diameter, independent of the degree of branching. However, SANS from linear PNIPAM above the LCST is described by a model that combines particulate structure and a contribution from solvated chains. NSE was used to study the internal and translational solution dynamics of HB-PNIPAM chains below the LCST. Internal HB-PNIPAM dynamics is described well by the Rouse model for non-entangled chains
The icephobic performance of alkyl-grafted aluminum surfaces
This work analyzes the anti-icing performance of flat aluminum surfaces coated with widely used alkyl-group based layers of octadecyltrimethoxysilane, fluorinated alkylsilane and stearic acid as they are subjected to repeated icing/deicing cycles. The wetting properties of the samples upon long-term immersion in water are also evaluated. The results demonstrate that smooth aluminum surfaces grafted with alkyl groups are prone to gradual degradation of their hydrophobic and icephobic properties, which is caused by interactions and reactions with both ice and liquid water. This implies that alkyl-group based monolayers on aluminum surfaces are not likely to be durable icephobic coatings unless their durability in contact with ice and/or water is significantly improved
Caracterização e avaliação de processos de seleção de resÃduos sólidos urbanos por meio da técnica de mapeamento
NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics
Xenarthrans – anteaters, sloths, and armadillos – have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with 24 domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, ten anteaters, and six sloths. Our dataset includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data-paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the south of the USA, Mexico, and Caribbean countries at the northern portion of the Neotropics, to its austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n=5,941), and Cyclopes sp. has the fewest (n=240). The armadillo species with the most data is Dasypus novemcinctus (n=11,588), and the least recorded for Calyptophractus retusus (n=33). With regards to sloth species, Bradypus variegatus has the most records (n=962), and Bradypus pygmaeus has the fewest (n=12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other datasets of Neotropical Series which will become available very soon (i.e. Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans dataset
ATLANTIC-CAMTRAPS: a dataset of medium and large terrestrial mammal communities in the Atlantic Forest of South America
Our understanding of mammal ecology has always been hindered by the difficulties of observing species in closed tropical forests. Camera trapping has become a major advance for monitoring terrestrial mammals in biodiversity rich ecosystems. Here we compiled one of the largest datasets of inventories of terrestrial mammal communities for the Neotropical region based on camera trapping studies. The dataset comprises 170 surveys of medium to large terrestrial mammals using camera traps conducted in 144 areas by 74 studies, covering six vegetation types of tropical and subtropical Atlantic Forest of South America (Brazil and Argentina), and present data on species composition and richness. The complete dataset comprises 53,438 independent records of 83 species of mammals, includes 10 species of marsupials, 15 rodents, 20 carnivores, eight ungulates and six armadillos. Species richness averaged 13 species (±6.07 SD) per site. Only six species occurred in more than 50% of the sites: the domestic dog Canis familiaris, crab-eating fox Cerdocyon thous, tayra Eira barbara, south American coati Nasua nasua, crab-eating raccoon Procyon cancrivorus and the nine-banded armadillo Dasypus novemcinctus. The information contained in this dataset can be used to understand macroecological patterns of biodiversity, community, and population structure, but also to evaluate the ecological consequences of fragmentation, defaunation, and trophic interactions. © 2017 by the Ecological Society of Americ
Quale futuro per il diritto allo studio? Principio di sussidiariet\ue0, autonomia universitaria e prospettive di riforma
- …