Double burden of malnutrition as a risk factor for overweight and obesity

OBJECTIVE To assess the longitudinal effect of double burden of malnutrition (DBM) on the risk of developing child and adolescent overweight or obesity. METHODS Analysis of the Peruvian Young Lives Study, younger cohort: baseline (2002) and 4 follow-ups (2006–2007, 2009–2010, 2013–2014, and 2016–2017). Outcomes were the incidence of overweight and obesity as defined by the World Health Organization standards. The exposure comprised a variable with 4 categories: non-stunted child with a non-overweight mother (reference group), non-stunted child with an overweight mother, stunted child with a non-overweight mother, and stunted child with an overweight mother (i.e., DBM). Poisson regression models were built to assess the association of interest, and relative risks (RR) and 95%CI were reported. RESULTS Data from 2,034 children; 50.0% were girls and the mean age was 12.0 (3.6) months at baseline. Non-stunted children with an overweight mother had greater risk (RR = 1.64; 95%CI: 1.35–1.99) of developing overweight, compared with the risk for stunted children with a non-overweight mother (RR = 1.38; 95%CI: 1.10–1.72), and for those with DBM (RR = 1.28; 95%CI: 1.02–1.61). When compared with the reference group, obesity risk was greater among non-stunted children with an overweight mother (RR = 2.33; 95%CI: 1.68–3.22), greater among stunted children with a non-overweight mother (RR = 2.59; 95%CI: 1.75–3.84), and greater among those with DBM (RR = 2.14; 95%CI: 1.39–3.28). CONCLUSIONS DBM is a risk factor for childhood overweight and obesity in Peru. Dual-duty policies tackling both undernutrition in children and overweight in mothers are needed to reduce DBM and its future effects in Peru

Lateral instability in normal viscous fingers

We study a low-amplitude, long-wavelength lateral instability of the Saffman-Taylor finger by means of a phase-field model. We observe such an instability in two situations in which small dynamic perturbations are overimposed to a constant pressure drop. We first study the case in which the perturbation consists of a single oscillatory mode and then a case in which the perturbation consists of temporal noise. In both cases the instability undergoes a process of selection

“Colmillos de sangre”: etnografías oníricas sobre las experiencias de ensoñación en jóvenes latinoamericanos residentes en la región de Los Lagos, Chile (2020-2023)

El articulo muestra reflexiones fenomenológicas a partir de una etnografía-narrativa sobre las experiencias de ensoñación que manifiestan jóvenes latinoamericanos residentes entre los años 2020-2023 en áreas urbanas de la región de Los Lagos, ciudades localizadas en la norpatagonia de Chile, a objeto de comprender las dimensiones culturales de la vida migrante y sus representaciones simbólicas asociadas con el mundo de los sueños. La metodología propuesta es, en un primer momento, pensada desde una etnografía especular que dialogaba con la interdisciplina, sobre todo en la elaboración de talleres participativos, los cuales permitieron la exploración del objeto de estudio desde las subjetividades como prácticas culturales que fueron narradas a través de la descripción densa. Los resultados muestran cómo las prácticas oníricas y las experiencias de ensoñación donde los sujetos interpretan sus experiencias vividas, se asociaban con la proyección de los significados migratorios en torno a sus estadías, deseos y demandas en Chile. Los aportes que hace este trabajo a los estudios migratorios son, precisamente, un tipo de conocimiento nuevo sobre las formas en las que los sujetos se relacionan e interaccionan en espacios de anclaje donde proyectan parte de sus experiencias basadas en el afrontamiento a los nuevos lugares de residencia, representaciones que bien pueden comprenderse como significados de la nostalgia, estados nerviosos y temores asociados con lo desconocido

Block copolymer-based magnetic mixed matrix membranes-effect of magnetic field on protein permeation and membrane fouling

In this study, we report the impact of the magnetic field on protein permeability through magnetic-responsive, block copolymer, nanocomposite membranes with hydrophilic and hydrophobic characters. The hydrophilic nanocomposite membranes were composed of spherical polymeric nanoparticles (NPs) synthesized through polymerization-induced self-assembly (PISA) with iron oxide NPs coated with quaternized poly(2-dimethylamino)ethyl methacrylate. The hydrophobic nanocomposite membranes were prepared via nonsolvent-induced phase separation (NIPS) containing poly (methacrylic acid) and meso-2, 3-dimercaptosuccinic acid-coated superparamagnetic nanoparticles (SPNPs). The permeation experiments were carried out using bovine serum albumin (BSA) as the model solute, in the absence of the magnetic field and under permanent and cyclic magnetic field conditions OFF/ON (strategy 1) and ON/OFF (strategy 2). It was observed that the magnetic field led to a lower reduction in the permeate fluxes of magnetic-responsive membranes during BSA permeation, regardless of the magnetic field strategy used, than that obtained in the absence of the magnetic field. Nevertheless, a comparative analysis of the effect caused by the two cyclic magnetic field strategies showed that strategy 2 allowed for a lower reduction of the original permeate fluxes during BSA permeation and higher protein sieving coefficients. Overall, these novel magneto-responsive block copolymer nanocomposite membranes proved to be competent in mitigating biofouling phenomena in bioseparation processes

Measurement Invariance of the Short UCLA Loneliness Scale in Spanish and Peruvian Old People: Latent Mean Differences and Evidence for Differential Effects on Perceived Health

The objectives of this study are to evaluate the measurement invariance of the University of California Los Angeles Loneliness Scale (UCLA-LS) three-item version (UCLA-LS-3) in older adults in Peru and Spain, to compare the latent means of loneliness, and to evaluate the psychometric properties of the scale with Item Response Theory (IRT) models, and evaluate the possible moderating effects of the country on loneliness-health relationships. Peruvian sample was composed of 235 old adults from the city of Lima. The Spanish sample was composed of 443 old adults. The three-factor structure of RUCLA-3 anchored to the health measure fitted the data reasonably well in Spain and Peru. The R-UCLA-3 may be considered invariant for these two samples. The latent means of loneliness are different, the Peruvian average of loneliness being greater than that of Spain. The R-UCLA-3 is an invariant measure in older adults in Peru and Spain, with adequate psychometric properties through IRT models

Exploring the surface-enhanced Raman scattering (SERS) activity of gold nanostructures embedded around nanogaps at wafer scale: Simulations and experiments

A unique way of converting free space light into a local electromagnetic field in small spaces is via metallic nanostructuring. In this work fabrication, experimental characterization and simulation of surface-enhanced Raman scattering (SERS) active specimens based on Au nanostructures are discussed. We used displacement Talbot lithography (DTL) to fabricate silicon nano-wedge substrates with Au nanostructures embedded around their apices. After the ion beam etching process, a nanogap is introduced between two Au nanostructures templated over nano-wedges, yielding specimens with SERS characteristics. The Au nanostructures and the nanogaps have symmetric and asymmetric configurations with respect to the wedges. With this nanofabrication method, various wafer-scale specimens were fabricated with highly controllable nanogaps with a size in the order of 6 nm for symmetric gaps and 8 nm for asymmetric gaps. SERS characteristics of these specimens were analyzed experimentally by calculating their analytical enhancement factor (AEF). According to finite-difference time-domain (FDTD) simulations, the Raman enhancement arises at the narrow gap due to plasmonic resonances, yielding a maximum AEF of 6.9 × 106. The results highlight the SERS activity of the nanostructures and ultimately comply with reliable substrates for practical applications

Overexpression of alpha-synuclein at non-toxic levels increases dopaminergic cell death induced by copper exposure via modulation of protein degradation pathways

Gene multiplications or point mutations in alpha (α)-synuclein are associated with familial and sporadic Parkinson’s disease (PD). An increase in copper (Cu) levels has been reported in the cerebrospinal fluid and blood of PD patients, while occupational exposure to Cu has been suggested to augment the risk to develop PD. We aimed to elucidate the mechanisms by which α-synuclein and Cu regulate dopaminergic cell death. Short-term overexpression of WT or A53T α-synuclein had no toxic effect in human dopaminergic cells and primary midbrain cultures, but it exerted a synergistic effect on Cu-induced cell death. Cell death induced by Cu was potentiated by overexpression of the Cu transporter protein 1 (Ctr1) and depletion of intracellular glutathione (GSH) indicating that the toxic effects of Cu are linked to alterations in its intracellular homeostasis. Using the redox sensor roGFP, we demonstrated that Cu-induced oxidative stress was primarily localized in the cytosol and not in the mitochondria. However, α-synuclein overexpression had no effect on Cu-induced oxidative stress. WT or A53T α-synuclein overexpression exacerbated Cu toxicity in dopaminergic cells and yeast in the absence of α-synuclein aggregation. Cu increased autophagic flux and protein ubiquitination. Impairment of autophagy by overexpression of a dominant negative Atg5 form or inhibition of the ubiquitin/proteasome system (UPS) with MG132 enhanced Cu-induced cell death. However, only inhibition of the UPS stimulated the synergistic toxic effects of Cu and α-synuclein overexpression. Our results demonstrate that α-synuclein stimulates Cu toxicity in dopaminergic cells independent from its aggregation via modulation of protein degradation pathways