Twisted One-Dimensional Charge Transfer and Related Y-Shaped Chromophores with a 4H-Pyranylidene Donor: Synthesis and Optical Properties.

Three series of push-pull derivatives bearing 4H-pyranylidene as electron donor group and a variety of acceptors were designed. On one hand, one-dimensional chromophores with a thiophene ring (series 1H) or 5-dimethylaminothiophene moiety (series 1N) as an auxiliary donor, non-coplanar with the π-conjugated system, were synthesized. On the other hand, related two-dimensional (2D) Y-shaped chromophores (series 2) were also prepared to compare how the diverse architectures affect the electrochemical, linear, and second-order nonlinear optical (NLO) properties. The presence of the 5-dimethylaminothiophene moiety in the exocyclic C═C bond of the pyranylidene unit gives rise to oxidation potentials rarely low, and the protonation (with an excess of trifluoroacetic acid) of its derivatives results in the apparition of a new blue-shifted band in the UV-visible spectra. The analysis of the properties of derivatives with and without the additional thiophene ring shows that this auxiliary donor leads to a higher NLO response, accompanied by an enhanced transparency. Y-shaped chromophores of series 2 present a blue-shifted absorption, higher molar extinction coefficients, and higher Eox values compared to their linear twisted counterparts. As concerns NLO properties, 2D Y-shaped architecture gives rise to somewhat lower µß values (except for thiobarbiturate derivatives).

(Super)gelators derived from push-pull chromophores: synthesis, gelling properties and second harmonic generation.

The present work takes advantage of the self-assembly process occurring along organogelation, to organize Second Harmonic Generation (SHG) active chromophores. To do so, three push-pull chromophores endowed with a dodecyl urea chain were synthesized and characterized. Their organogelating properties were studied in a wide range of solvents. Despite similar architectures, these derivatives exhibit very different gelling properties, from supergelation to the absence of gelling ability. The utilization of the Hansen solubility parameters allows for observing clear relationships between the gelled solvents and critical gelation concentrations. By evaporating the solvents from the organogels, xerogel materials were prepared and systematically studied by means of optical and electron microscopy as well as SHG microscopy. These studies demonstrate the critical role of the solvent over material structuring and allow generalizing the approach exploiting organogelation as a structuring tool to spontaneously organize push-pull chromophores into SHG-active materials.

Promoting Spontaneous Second Harmonic Generation through Organogelation.

An organogelator based on the Disperse Red nonlinear optical chromophore was synthesized according to a simple and efficient three-step procedure. The supramolecular gel organization leads to xerogels which display a spontaneous second harmonic generation (SHG) response without any need for preprocessing, and this SHG activity appears to be stable over several months. These findings, based on an intrinsic structural approach, are supported by favorable intermolecular supramolecular interactions, which promote a locally non-centrosymmetric NLO-active organization. This is in sharp contrast with most materials designed for SHG purposes, which generally require the use of expensive or heavy-to-handle external techniques for managing the dipoles' alignment.

D-π-A Compounds with Tunable Intramolecular Charge Transfer Achieved by Incorporation of Butenolide Nitriles as Acceptor Moieties.

Chromophores where a polyenic spacer separates a 4H-pyranylidene or benzothiazolylidene donor and three different butenolide nitriles have been synthesized and characterized. The role of 2(5H)-furanones as acceptor units on the polarization and the second-order nonlinear (NLO) properties has been studied. Thus, their incorporation gives rise to moderately polarized structures with NLO responses that compare favorably to those of related compounds featuring more efficient electron-withdrawing moieties. Derivatives of the proaromatic butenolide PhFu show the best nonlinearities. Benzothiazolylidene-containing chromophores present less alternated structures than their pyranylidene analogues, and, unlike most merocyanines, the degree of charge transfer does not decrease on lengthening the π-bridge.

Phosphonic anchoring groups in organic dyes for solid-state solar cells.

We report the synthesis and the optoelectronic characterization of three new 4H-pyran-4-ylidene and thiazole derivatives (pyt) as metal-free organic dyes for solid-state dye-sensitized solar cells (DSSCs). We investigate the performance and the long-term stability of devices employing pyt dyes functionalized with carboxylic and phosphonic acids as TiO2 anchoring groups. In contrast to reports on liquid electrolyte DSSCs, we show that solid-state DSSCs prepared with phosphoric pyt derivatives can achieve similar power conversion efficiency to their carboxyl analogues. We make use of the Mott-Schottky analysis and equivalent circuit models to demonstrate that a phosphonic group induces a significant increase in built-in voltage at the TiO2-hole transporter interface, which results in a higher open circuit voltage.

Push-pull systems bearing a quinoid/aromatic thieno[3,2-b]thiophene moiety: synthesis, ground state polarization and second-order nonlinear properties.

Chromophores bearing a 2-dicyanomethylenethieno[3,2-b]thiophene moiety in their quinoidal form have been synthesized, exploring for the first time the reactivity of this system towards aldehydes. Their ground state polarization and linear and second-order nonlinear optical (NLO) properties have been determined by a combined experimental and theoretical study, and compared to those of analogous compounds featuring an aromatic thienothiophene unit. Due to the gaining of aromaticity, quinoid systems have been found to display more polarized electronic ground states and higher NLO responses with respect to their aromatic counterparts.

Novel Spiro-Core Dopant-Free Hole Transporting Material for Planar Inverted Perovskite Solar Cells.

Hole-transporting materials (HTMs) have demonstrated their crucial role in promoting charge extraction, interface recombination, and device stability in perovskite solar cells (PSCs). Herein, we present the synthesis of a novel dopant-free spiro-type fluorine core-based HTM with four ethoxytriisopropylsilane groups (Syl-SC) for inverted planar perovskite solar cells (iPSCs). The thickness of the Syl-SC influences the performance of iPSCs. The best-performing iPSC is achieved with a 0.8 mg/mL Syl-SC solution (ca. 15 nm thick) and exhibits a power conversion efficiency (PCE) of 15.77%, with Jsc = 20.00 mA/cm2, Voc = 1.006 V, and FF = 80.10%. As compared to devices based on PEDOT:PSS, the iPSCs based on Syl-SC exhibit a higher Voc, leading to a higher PCE. Additionally, it has been found that Syl-SC can more effectively suppress charge interfacial recombination in comparison to PEDOT:PSS, which results in an improvement in fill factor. Therefore, Syl-SC, a facilely processed and efficient hole-transporting material, presents a promising cost-effective alternative for inverted perovskite solar cells.

Expression of Circulating MicroRNAs Associated with Obesity and their Relationships with Biochemical Parameters and Health-related Physical Fitness in Children 6 to 10 Years Old in Cali, Colombia.

BACKGROUND: Obesity is a public health problem worldwide; it has reached pandemic proportions in the last 40 years. Its prevalence in children and adolescents increased from 0.7% to 7.8% between 1975 and 2016. Recently, microRNAs (miRNAs) have been reported as regulatory factors related to molecular functions under different conditions. These can be used as biomarkers of a disease to estimate risks in the early stages. OBJECTIVE: This study aimed to determine the expression levels of miRNAs associated with childhood obesity and their relationships with biochemical parameters and Health-related Physical Fitness (HRPF). METHODS: This was a descriptive cross-sectional study in which a population of 40 children between 6 and 10 years of age of both sexes from Cali, Colombia, was evaluated; the children were classified as 20 normal-weight and 20 obese. Blood biochemistry, HRPF, and miRNA expression levels were determined (hsa-miR-122-5p, hsa-miR-15b-5p, hsa-miR-191-5p, hsa-miR-486-3p, hsa-miR-222-3p. Comparisons were made between the groups, miRNA associations between the studied variables, and linear regression analysis. RESULTS: Twenty normal-weight and 20 obese patients were evaluated. Both groups had an average age of eight years old. The miRNA hsa-miR-122-5p (p < 0.05) was overexpressed in the obese group. According to the linear regression analysis, the amount of adipose tissue may be associated with the production of miRNAs (hsa-miR-15b-5p, hsa-miR-222-3p, hsa-miR-122-5p, and hsamiR- 191-5p). CONCLUSION: Four miRNAs (hsa-miR-15b-5p, hsa-miR-222-3p, hsa-miR-122-5p, and hsa-miR- 191-5p) are associated with modifications in biochemical variables of HRPF in this group. Adipose tissue mass could be associated with the production of these miRNAs, thus making them biomarkers of childhood obesity risk.

Multichromophoric calix[4]arenes: effect of interchromophore distances on linear and nonlinear optical properties.

Multichromophoric calix[4]arenes with two or four disperse red one (DR1) moieties linked to the lower rim have been synthesized. The second-order nonlinear optical activity was measured by using the electric-field-induced second-harmonic generation technique and there was a nearly linear increase of the µß value with the number of chromophores in the molecule without affecting the charge-transfer absorption wavelength. The effect that the number of DR1 units plays on the hyperpolarizability, the dipole moment, and the absorption maxima has been also studied by using quantum chemical calculations. It was found that it was necessary to synthesize multichromophores with distant chromophores to obtain large nonlinear optical responses.

Synthesis, characterization, and optical properties of 4H-pyran-4-ylidene donor-based chromophores: the relevance of the location of a thiophene ring in the spacer.

A series of new 4H-pyran-4-ylidene donor-based chromophores with a thiophene ring in the spacer has been synthesized. The linear and nonlinear optical (NLO) properties of these compounds have been determined and compared with the results of computational calculations. The position of the thiophene ring proved essential to optimize the figure of merit µß, with the best results obtained when the heterocyclic system was closer to the donor moiety.

Notes on current Mbyá-Guarani medicinal plant exchanges in southern Brazil.

BACKGROUND: Experts in the Atlantic Forest, the Guarani people have the habit of transporting and exchanging plants due to their mobility throughout the territory. Historically, this habit contributed to the species composition and diversification among different phytophysiognomies that comprise the Atlantic Forest. Medicine and spirituality are traits that stand out within the Guarani culture, which is based on a holistic understanding of physical and spiritual well-being for the person's health. To achieve this balance, they use a range of native and adapted plant species. Our goal is to understand some of the Guarani contributions to the cultural landscape in the Atlantic Forest. METHODS: We conducted semi-structured interviews with key persons asking about the importance of forest environments for Guarani health and about visits to other Guarani villages and plants exchanged. Data analysis was qualitative, and through a bipartite network of exchanged plants to show current plant exchanges between villages. RESULTS: We visited seven Guarani Indigenous Territories in south Brazil, and with the participation of 12 respondents, we registered 27 species that were exchanged through different phytophysiognomies in the Atlantic Forest. These results show an intense movement of plants currently occurring between villages and the importance of these movements for both individual health and the integrity of the environments in which the Guarani villages are inserted. CONCLUSIONS: We observed a search for the maintenance of traditional species in the Guarani medical system, and we highlight the fundamental role of Guarani management in the conservation of the southern Atlantic Forest in indigenous territories.

4H-Pyran-4-ylidenes: strong proaromatic donors for organic nonlinear optical chromophores.

Merocyanines where a polyenic spacer separates a 4H-pyran-4-ylidene moiety and different strong organic acceptors have been synthesized. According to NMR studies and X-ray diffraction data, these compounds have weakly alternated structures and remarkably zwitterionic ground states, with a partial aromatic character that is compared to those of other pyran derivatives. The proaromaticity of the 4H-pyran-4-ylidene donor lies behind the cyanine-like behavior and low (positive or negative) second-order optical nonlinearities of the shorter derivatives. On the other hand, lengthening the pi-spacer gives rise to rapidly increasing mubeta(1907) values up to 17,400 x 10(-48) esu.

Chemical characterization and bioactive properties of a coffee-like beverage prepared from Quercus cerris kernels.

In the present study, a coffee-like beverage was prepared from Quercus cerris seeds. Seeds presented 60.4% carbohydrates (of which 26.9% is fiber), 6.3% proteins and 4.0% fat. In the coffee-like beverage, the TPC and TFC were 2070.2 mg GAE per L and 285.3 mg CEQ per L, respectively. The IC50 values determined using FRAP and DPPH assays were, respectively, 203.1 mg L-1 and 271.6 mg L-1. Concerning the reactive species scavenging capacity, the extract was more effective against O2˙-, HClO and ˙NO (namely, IC50 = 17.24 ± 0.24 µg mL-1, IC50 = 9.25 ± 0.92 µg mL-1 and IC50 = 0.65 ± 0.06 µg mL-1). Qualitative and quantitative analyses by 1D- and 2D-NMR and LC-MS indicated high levels of ellagic acid and gallotannin or ellagitannin derivatives. The optimal range of non-cytotoxic concentrations in Caco-2 and HT29-MTX cell lines was between 0.1 and 1.0 µg mL-1. This is the first study that evaluates the Q. cerris seed extract as a beverage.

Iminium salts of omega-dithiafulvenylpolyenals: an easy entry to the corresponding aldehydes and doubly proaromatic nonlinear optic-phores.

A short, high-yielding route to omega-dithiafulvenylpolyenals (1) via the corresponding iminium salts (2) and starting from trimethyl-1,3-dithiolium tetrafluoroborate is reported. The Knoevenagel reactions of either 1 or 2 with isoxazolone-containing acceptors afford merocyanines 7 and 9, in a process that is often accompanied by a vinylene-shortening side reaction. Experimental and theoretical studies reveal that compounds 7 and 9, featuring two proaromatic end groups, are strongly polarized and show good second-order nonlinear optical responses.

Sarcopenia in community-dwelling persons over 60 years of age from a northern spanish city: relationship between diagnostic criteria and association with the functional performance.

INTRODUCTION: Sarcopenia is a recognized problem in older people. Currently, its diagnosis goes beyond a simple loss of muscle mass. The aim of this study was to determine the frequency of sarcopenia, defined by the European Working Group on Sarcopenia in Older People (EWGSOP), in independent persons over 60 years of age from a northern Spanish city. In addition, this study compared the diagnostic criteria for sarcopenia and assessed the differences in functional performance according to them. METHODS: A cross-sectional study was carried out on 258 members of community centers of both genders. Body composition was assessed with dual-energy X-ray absorptiometry. Appendicular lean mass index (App LMI), hand grip strength (HGS), and 8 foot up-and-go test (8f-UG) were used to diagnose sarcopenia. RESULTS: The frequency of sarcopenia was 2.4% (n=6). In women, the App LMI was correlated with HGS (r= 0.164, p<0.05) and 8f­UG (r= -0.167, p<0.05), while in men, the App LMI was correlated with HGS (r=0.241, p<0.05) but not with 8f­UG (r= -0.173, p=0.117). The subjects with low HGS and low performance in the 8f­UG presented lower values in other functional outcomes than people with low App LMI (p<0.05). CONCLUSIONS: Using the EWGSOP definition, the frequency of sarcopenia was low in a group of individuals over 60 years of age from a northern Spanish city. In clinical practice, greater emphasis should be placed on the decrease in muscle strength and functional performance rather than on low muscle mass alone.

Introducción: La sarcopenia es un problema reconocido en la personas mayores. Actualmente, su diagnóstico va más allá de una simple pérdida de la masa muscular. El objetivo de este estudio fue determinar la frecuencia de sarcopenia definida por el European Working Group on Sarcopenia in Older People (EWGSOP), en personas mayores de 60 años con vida independiente de una ciudad del norte de España. Además, el estudio comparó los criterios diagnósticos para sarcopenia y evaluó las diferencias en el rendimiento funcional de acuerdo a ellos. Métodos: Se realizó un estudio transversal con 258 personas de ambos géneros, pertenecientes a centros comunitarios. La composición corporal se evaluó con absorciometría dual por rayos-X. El índice de masa magra apendicular (IMMA), la fuerza de prensión manual (FPM) y el 8 foot up­and­go test (8f­UG) fueron empleados para el diagnóstico de sarcopenia. Resultados: La frecuencia de sarcopenia fue de 2.4% (n=6). En las mujeres, el IMMA se correlacionó con el FPM (r= 0.164, p.

Dithienopyrrole as a rigid alternative to the bithiophene π relay in chromophores with second-order nonlinear optical properties.

4H-Pyranylidene-containing push-pull chromophores built around a bithiophene (BT) π relay or a rigidified thiophene-based unit, namely cyclopenta[1,2-b:3,4-b']dithiophene (CPDT) or dithieno[3,2-b:2',3'-d]pyrrole (DTP), have been synthesized and characterized. The effect of these different relays on the polarization and the second-order nonlinear optical (NLO) properties has been studied. For the sake of comparison, the corresponding reported dithieno[3,2-b:2',3'-d]thiophene (DTT) derivatives have also been included in the discussion. Replacement of the BT core by a rigidified unit (CPDT, DTP) leads to more polarized systems. Calculated NBO charges and electrochemical measurements show that dithienopyrrole has a remarkable donor character that allows an important charge transfer between the donor and the acceptor. The influence of the rigidification of the BT relay on the NLO responses depends on the acceptor strength. For the weakest acceptor used (thiobarbituric acid), passing from the BT relay to the rigidified units always involves an increase in the µß0 figure of merit. Nevertheless, for the strongest acceptor (2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran (TCF)), a slight increase in µß0 with respect to the BT chromophore is only observed for the DTP derivative. Thus, rigidification of the BT core is not enough to improve the second-order nonlinearity and the incorporation of a DTP moiety has proven to be the most efficient approach for this purpose.

New D-π-A-conjugated organic sensitizers based on 4H-pyran-4-ylidene donors for highly efficient dye-sensitized solar cells.

We have synthesized a series of four new promising D-π-A conjugated organic sensitizers with a proaromatic 4H-pyran-4-ylidene as a donor, a thiophene ring in the bridge, and 2-cyanoacrilic acid as acceptor. Comparison between different donor substituents and the modification of the thiophene ring resulted in molar extinction coefficients as high as 36399 M(-1) cm(-1) at 551 nm. The photovoltaic properties of the DSSCs demonstrate power conversion efficiencies as high as 5.4%.

Sarcopenia in community-dwelling persons over 60 years of age from a northern Spanish city: relationship between diagnostic criteria and association with the functional performance / Sarcopenia en personas mayores de 60 años residentes en la comunidad de una ciudad del norte de España: relación entre sus criterios diagnósticos y asociación con el rendimiento funcional

Introduction: Sarcopenia is a recognized problem in older people. Currently, its diagnosis goes beyond a simple loss of muscle mass. The aim of this study was to determine the frequency of sarcopenia, defined by the European Working Group on Sarcopenia in Older People (EWGSOP), in independent persons over 60 years of age from a northern Spanish city. In addition, this study compared the diagnostic criteria for sarcopenia and assessed the differences in functional performance according to them. Methods: A cross–sectional study was carried out on 258 members of community centers of both genders. Body composition was assessed with dual–energy X–ray absorptiometry. Appendicular lean mass index (App LMI), hand grip strength (HGS), and 8 foot up–and–go test (8f–UG) were used to diagnose sarcopenia. Results: The frequency of sarcopenia was 2.4% (n=6). In women, the App LMI was correlated with HGS (r= 0.164, p< 0.05) and 8f–UG (r= -0.167, p< 0.05), while in men, the App LMI was correlated with HGS (r=0.241, p< 0.05) but not with 8f–UG (r= -0.173, p=0.117). The subjects with low HGS and low performance in the 8f– UG presented lower values in other functional outcomes than people with low App LMI (p< 0.05). Conclusions: Using the EWGSOP definition, the frequency of sarcopenia was low in a group of individuals over 60 years of age from a northern Spanish city. In clinical practice, greater emphasis should be placed on the decrease in muscle strength and functional performance rather than on low muscle mass alone (AU)

Introducción: La sarcopenia es un problema reconocido en la personas mayores. Actualmente, su diagnóstico va más allá de una simple pérdida de la masa muscular. El objetivo de este estudio fue determinar la frecuencia de sarcopenia definida por el European Working Group on Sarcopenia in Older People (EWGSOP), en personas mayores de 60 años con vida independiente de una ciudad del norte de España. Además, el estudio comparó los criterios diagnósticos para sarcopenia y evaluó las diferencias en el rendimiento funcional de acuerdo a ellos. Métodos: Se realizó un estudio transversal con 258 personas de ambos géneros, pertenecientes a centros comunitarios. La composición corporal se evaluó con absorciometría dual por rayos-X. El índice de masa magra apendicular (IMMA), la fuerza de prensión manual (FPM) y el 8 foot up–and–go test (8f–UG) fueron empleados para el diagnóstico de sarcopenia. Resultados: La frecuencia de sarcopenia fue de 2.4% (n=6). En las mujeres, el IMMA se correlacionó con el FPM (r= 0.164, p< 0.05) y 8f–UG (r= -0.167, p< 0.05) pero no con el 8f–UG (r= -0.173, p=0.117). Los participantes con baja FPM y bajo rendimiento funcional en el 8f–UG presentaron valores más bajos en otros resultados funcionales que las personas con un bajo IMMA (p< 0.05). Conclusiones: al emplear la definición del EWGSOP, la frecuencia de sarcopenia fue baja en un grupo de personas mayores de 60 años de una ciudad del norte de España. En la práctica clínica, debe hacerse más énfasis en la disminución de la fuerza muscular y el rendimiento funcional, que en la baja masa muscular únicamente (AU)

Decreased optical nonlinearities upon CF3 substitution on tricyanofuran acceptors.

Replacement of the tricyanofuran (TCF) acceptor by its stronger analogue CF 3-TCF results in decreased second-order optical nonlinearities in merocyanines bearing a proaromatic 1,3-dithiole donor. The TCF-containing derivatives display exceptionally high mu beta values up to 31,000 x 10(-48) esu, unprecedented for 1,3-dithiole-based NLO-phores.

Synthesis, structure, and optical properties of 1,4-dithiafulvene-based nonlinear optic-phores.

Polyenic nonlinear optic (NLO)-phores with a proaromatic 1,4-dithiafulvene electron donor and the little explored 1,1,3-tricyano-2-phenylpropene acceptor have been synthesized. Their configurational and conformational features, ground state polarization, and linear and nonlinear optical properties have been determined experimentally and theoretically, and the results are compared to those of tetrathiafulvalene-related derivatives. The newly prepared compounds show close to optimal bond length alternation values for maximizing the first molecular hyperpolarizability, and one of them displays the highest mu beta0 value ever reported for a dithiafulvene-based NLO-phore. The first example of a dithiafulvenylmethylene transfer reaction is also reported.