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showing 10 items of 32550 documents
Hacer espacios en patrimonialización. Prácticas cotidianas en la formación del 'Paisaje Cultural Cafetero' de Colombia - Patrimonio Mundial
2017
Esta tesis analiza la patrimonialización del ‘Paisaje Cultural Cafetero’ de Colombia, inscrito en la Lista de Patrimonio Mundial desde 2011. Se refiere a un contexto rural andino especializado en la producción de café, donde la pequeña agricultura ha perdido rentabilidad económica tras la liberalización del mercado. El patrimonio paisajístico se proyecta allí como medida de conservación, revitalización económica y pacificación. La investigación se pregunta por el efecto cotidiano de este patrimonio, diseñado en nombre de pequeños agricultores. Plantea un seguimiento etnográfico a las prácticas de productivas de café, durante los cinco años posteriores al reconocimiento de la UNESCO (2011-20…
Psychosocial Risk Factors and Psychopathological Outcomes: Preliminary Findings in Italian Pregnant Women
2023
The perinatal period may represent a particularly challenging time for expecting parents. Previous studies have highlighted an association between several perinatal risk conditions (e.g., childhood maltreatment, poor social support, and stress levels) and the development of psychopathological symptoms in pregnant women, especially depression symptoms. The current study examined the effects of psychosocial risk factors (childhood maltreatment, poor social support, and stressful events) on anxiety, depression, perceived stress, irritability/anger, relationship problems, psychosomatic symptoms, specific physiological problems, and addiction/at-risk behaviors. Sixty-one pregnant women (age rang…
Levels and Changes of Physical Activity in Adolescents during the COVID-19 Pandemic: Contextualizing Urban vs. Rural Living Environment
2020
The COVID-19 pandemic and the social distancing implemented shortly after influence physical activity levels (PALs). The purpose of this investigation was to evaluate the changes in PAL and factors associated with PALs among Croatian adolescents while considering the impact of community (urban vs. rural living environment). The sample included 823 adolescents (mean age: 16.5 ±
Public Libraries – Facilitators of Information Society and e- Inclusion in Latvia
2014
Abstract The economic growth and national competitiveness is closely correlated with the development of information society. In the last few years the role of public libraries has significantly increased and libraries have greatly contributed to the improvement of information society in Latvia. The usage of library services had never been as high as they were in 2011 – 42% of the population were active library users and 90% of them used the Internet. Nowadays, the public library network in Latvia provides a powerful network of information, knowledge and community centres and they are highly demanded by society.
Ultrafast Interface Charge Separation in Carbon Nanodot-Nanotube Hybrids
2021
Carbon dots are an emerging family of zero-dimensional nanocarbons behaving as tunable light harvesters and photoactivated charge donors. Coupling them to carbon nanotubes, which are well-known electron acceptors with excellent charge transport capabilities, is very promising for several applications. Here, we first devised a route to achieve the stable electrostatic binding of carbon dots to multi- or single-walled carbon nanotubes, as confirmed by several experimental observations. The photoluminescence of carbon dots is strongly quenched when they contact either semiconductive or conductive nanotubes, indicating a strong electronic coupling to both. Theoretical simulations predict a favo…
Energy level determination of purine containing blue light emitting organic compounds
2018
Organic light emitting diodes (OLED) have found their applications in the mobile and TV screens. Till now the commercially available diodes are made by expensive thermal evaporation in a vacuum. The costs of OLED fabrication could be decreased by applying low-cost wet casting methods, for example, spin-coating. In this work, we have studied a group of blue light emitting purine derivatives which could potentially be used in OLEDs. The advantage of these compounds is their ability to form amorphous thin films from solutions. All the thin films were prepared by the spincoating method from chloroform solution on ITO glass. The position of hole and electron transport energy levels is important …
Intramolecular Hydrogen Bond, Hirshfeld Analysis, AIM; DFT Studies of Pyran-2,4-dione Derivatives
2021
Intra and intermolecular interactions found in the developed crystals of the synthesized py-ron-2,4-dione derivatives play crucial rules in the molecular conformations and crystal stabili-ties, respectively. In this regard, Hirshfeld calculations were used to quantitatively analyze the different intermolecular interactions in the crystal structures of some functionalized py-ran-2,4-dione derivatives. The X-ray structure of pyran-2,4-dione derivative namely (3E,3′E)-3,3′-((ethane-1,2-diylbis(azanediyl))bis(phenylmethanylylidene))bis(6-phenyl-2H-pyran-2,4(3H)-dione) was determined. It crystallized in the monoclinic crystal system and C2/c space group with unit cell parameters: a = 14.0869(4) …
Crystal structure of the pyridine–diiodine (1/1) adduct
2015
In the title adduct, C5H5N·I2, the N—I distance [2.424 (8) Å] is remarkably shorter than the sum of the van der Waals radii. The line through the I atoms forms an angle of 78.39 (16)° with the normal to the pyridine ring.
Halogen Bonds in 2,5-Dihalopyridine-Copper(I) Halide Coordination Polymers
2019
Two series of 2,5-dihalopyridine-Cu(I)A (A = I, Br) complexes based on 2-X-5-iodopyridine and 2-X-5-bromopyridine (X = F, Cl, Br and I) are characterized by using single-crystal X-ray diffraction analysis to examine the nature of C2&minus
Rayleigh-instability-driven dewetting of thin Au and Ag films on indium-tin-oxide surface under nanosecond laser irradiations
2013
Investigations have been carried out on laser-beam-induced nanoparticle (NP) formation in thin (5 nm) Au and Ag films on indium-tin-oxide substrate. After the irradiation the films were observed to break-up into NPs through a dewetting mechanism. This mechanism was investigated as a Rayleigh-instability- driven process. In fact, for each used laser fluence, the resulting Au and Ag NPs' mean size and surface-to-surface mean distance were quantified and correlated between them in the framework of the Rayleigh-instability theory showing an excellent agreement. © The Institution of Engineering and Technology 2013.