1,026 research outputs found
Parametric Surfaces for Augmented Architecture representation
Augmented Reality (AR) represents a growing communication channel, responding to the need to expand reality with additional information, offering easy and engaging access to digital data. AR for architectural representation allows a simple interaction with 3D models, facilitating spatial understanding of complex volumes and topological relationships between parts, overcoming some limitations related to Virtual Reality. In the last decade different developments in the pipeline process have seen a significant advancement in technological and algorithmic aspects, paying less attention to 3D modeling generation. For this, the article explores the construction of basic geometries for 3D model’s generation, highlighting the relationship between geometry and topology, basic for a consistent normal distribution. Moreover, a critical evaluation about corrective paths of existing 3D models is presented, analysing a complex architectural case study, the virtual model of Villa del Verginese, an emblematic example for topological emerged problems. The final aim of the paper is to refocus attention on 3D model construction, suggesting some "good practices" useful for preventing, minimizing or correcting topological problems, extending the accessibility of AR to people engaged in architectural representation
Solidarity with disabled people in times of crisis: A comparative analysis of Italy and the UK
Against the background of crisis and cuts, citizens can express solidarity with groups in various ways. Using novel survey data this article explores the attitudes and behaviours of citizens in their expressions of solidarity with disabled people and in doing so illuminates the differences and similarities across two European contexts: Italy and the UK. The findings reveal pools of solidarity with disabled people across both countries that have on the one hand similar foundations such as the social embeddedness and social trust of citizens, while on the other hand contain some differences, such as the more direct and active nature of solidarity in Italy compared to the UK and the role of religiosity as an important determinant, particularly in Italy. Across both countries the role of ‘deservingness’ was key to understanding solidarity, and the study’s conclusions raise questions about a solidarity embedded by a degree of paternalism and even religious piety
[BMIm][BARF] imidazolium salt solutions in alkyl carbonate solvents: Structure and interactions
Solutions of weakly coordinating ionic liquids (ILs) in alkyl carbonates are gaining growing attention, as the latter are "green" solvents with high solvation power, but the phase behavior and structure of ILs in organic polar solvents are still poorly understood. Here, we study the interactions and nanoscale structure of 1-butyl-3-methylimidazolium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate, [BMIm][BARF], in three symmetrical alkyl carbonate solvents with increasing alkyl chain-length. Electrical conductivity and nuclear magnetic resonance measurements showed that [BMIm][BARF] was mostly undissociated in these solvents, especially at lower IL concentration. Small angle X-ray scattering patterns evidenced the presence of rod-like nanostructures in the IL/solvent mixtures. At higher IL concentration, [BMIm][BARF] is increasingly more dissociated in solvents with lower dielectric constant, as confirmed by analysis of the solvents' carbonyl stretching band via Fourier transform infrared spectroscopy. This trend is opposite to that exhibited by BMIm ILs with less bulky counterions. The bulky BARF(-) is weakly coordinating and has no ability to give strong H-bonding, thus short-range anisotropic van der Waals forces are likely key in the interaction of the ion pairs. The slower self-diffusion of the ions in alkyl carbonates with lower dielectric constants might partially hinder close contact needed for self-assembly into local nano-sized structures. Overall, our results shed light on interactions and self-organization in imidazolium salt-alkyl carbonate mixtures, with potential impact in applicative fields spanning from batteries, catalysis and extraction, up to bio-applications (antimicrobial and bioengineering)
Rational Design of Sustainable Liquid Microcapsules for Spontaneous Fragrance Encapsulation
The high volatility, water-immiscibility, and light/oxygen-sensitivity of most aroma compounds represent a challenge to their incorporation in liquid consumer products. Current encapsulation methods entail the use of petroleum-based materials, initiators, and crosslinkers as well as mixing, heating, and purification steps. Hence, more efficient and eco-friendly approaches to encapsulation must be sought. Herein, we propose a simple method by making use of a pre-formed amphiphilic polymer and employing the Hansen Solubility Parameters approach to determine which fragrances could be encapsulated by spontaneous coacervation in water. The coacervates do not precipitate as solids but they remain suspended as colloidally stable liquid microcapsules, as demonstrated by fluorescence correlation spectroscopy. The effective encapsulation of fragrance is proven through confocal Raman spectroscopy, while the structure of the capsules is investigated by means of cryo FIB/SEM, confocal laser scanning microscopy, and small-angle X-ray scattering
Observation of Fragile-to-Strong Dynamic Crossover in Protein Hydration Water
At low temperatures proteins exist in a glassy state, a state which has no
conformational flexibility and shows no biological functions. In a hydrated
protein, at and above 220 K, this flexibility is restored and the protein is
able to sample more conformational sub-states, thus becomes biologically
functional. This 'dynamical' transition of protein is believed to be triggered
by its strong coupling with the hydration water, which also shows a similar
dynamic transition. Here we demonstrate experimentally that this sudden switch
in dynamic behavior of the hydration water on lysozyme occurs precisely at 220
K and can be described as a Fragile-to-Strong dynamic crossover (FSC). At FSC,
the structure of hydration water makes a transition from predominantly
high-density (more fluid state) to low-density (less fluid state) forms derived
from existence of the second critical point at an elevated pressure.Comment: 6 pages (Latex), 4 figures (Postscript
Mode-coupling theory predictions for a limited valency attractive square-well model
Recently we have studied, using numerical simulations, a limited valency
model, i.e. an attractive square well model with a constraint on the maximum
number of bonded neighbors. Studying a large region of temperatures and
packing fractions , we have estimated the location of the liquid-gas
phase separation spinodal and the loci of dynamic arrest, where the system is
trapped in a disordered non-ergodic state. Two distinct arrest lines for the
system are present in the system: a {\it (repulsive) glass} line at high
packing fraction, and a {\it gel} line at low and . The former is
essentially vertical (-controlled), while the latter is rather horizontal
(-controlled) in the plane. We here complement the molecular
dynamics results with mode coupling theory calculations, using the numerical
structure factors as input. We find that the theory predicts a repulsive glass
line -- in satisfactory agreement with the simulation results -- and an
attractive glass line which appears to be unrelated to the gel line.Comment: 12 pages, 6 figures. To appear in J. Phys. Condens. Matter, special
issue: "Topics in Application of Scattering Methods for Investigation of
Structure and Dynamics of Soft Condensed Matter", Fiesole, November 200
Increased susceptibility to amyloid toxicity in familial Alzheimer's fibroblasts
Much experimental evidence suggests that an imbalance in cellular redox status is a major factor in the pathogenesis of Alzheimer's disease (AD). Our previous data showed a marked increase in membrane lipoperoxidation in primary fibroblasts from familial AD (FAD) patients. In the present study, we demonstrate that when oligomeric structures of A beta 1-40 and A beta 1-42 are added to the culture media, they accumulate quicker near the plasma membrane, and are internalized faster and mostly in APPV717I fibroblasts than in age-matched healthy cells; this results in an earlier and sharper increase in the production of reactive oxygen species (ROS). Higher ROS production leads in turn to an increase in membrane oxidative-injury and significant impairment of cellular antioxidant capacity, giving rise to apoptotic cascade activation and finally to a necrotic outcome. In contrast, healthy fibroblasts appear more resistant to amyloid oxidative-attack, possibly as a result of their plasma membrane integrity and powerful antioxidant capacity. Our data are consistent with increasing evidence that prefibrillar aggregates, compared to mature fibrils, are likely the more toxic species of the peptides. These findings provide compelling evidence that cells bearing increased membrane lipoperoxidation are more susceptible to aggregate toxicity as a result of their reduced ability to counteract amyloid oligomeric attack
Effect of lithium encapsulation by a macrocyclic aza cage in micellar solutions of lithium dodecyl sulfate
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