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Elena Navarro-Palomares,1 Lorena García-Hevia,1 Jesús Galán-Vidal,2 Alberto Gandarillas,2 Fe García-Reija,3 Ana Sánchez-Iglesias,4,5 Luis M Liz-Marzán,4,5 Rafael Valiente,1,6 Mónica L Fanarraga1 1The Nanomedicine Group, Valdecilla Health Research Institute IDIVAL, Universidad de Cantabria, Santander, 39011, Spain; 2Cell Cycle, Stem Cell Fate & Cancer Laboratory, Valdecilla Health Research Institute IDIVAL, Santander, 39011, Spain; 3Oral and Maxillofacial Surgery Unit, Valdecilla Hospital HUVM, Santander, Spain; 4CIC biomaGUNE, Basque Research and Technology Alliance (BRTA), and CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), San Sebastián, 20014, Spain; 5Ikerbasque, Basque Foundation for Science, Bilbao, 48009, Spain; 6Dpt. Applied Physics, Facultad de Ciencias, Universidad de Cantabria, Santander, 39005, SpainCorrespondence: Mónica L Fanarraga; Lorena García-Hevia, Valdecilla Health Research Institute IDIVAL, University of Cantabria, Avda Herrera Oria s/n, Santander, 39011, Spain, Tel +34 942315515 Ext. 74101, Email fanarrag@unican.es; lgarcia@idival.orgIntroduction: A great challenge in nanomedicine, and more specifically in theranostics, is to improve the specificity, selectivity, and targeting of nanomaterials towards target tissues or cells. The topical use of nanomedicines as adjuvants to systemic chemotherapy can significantly improve the survival of patients affected by localized carcinomas, reducing the side effects of traditional drugs and preventing local recurrences.Methods: Here, we have used the Shiga toxin, to design a safe, high-affinity protein-ligand (ShTxB) to bind the globotriaosylceramide receptor (GB3) that is overexpressed on the surfaces of preneoplastic and malignant cancer cells in the head and neck tumors.Results: We find that ShTxB functionalized gold nanorods are efficiently retrotranslocated to the GB3-positive cell cytoplasms. After 3 minutes of laser radiation with a wavelength resonant with the AuNR longitudinal localized surface plasmon, the death of the targeted cancer cells is activated. Both preclinical murine models and patient biopsy cells show the non-cytotoxic nature of these functionalized nanoparticles before light activation and their treatment selectivity.Discussion: These results show how the use of nanomedicines directed by natural ligands can represent an effective treatment for aggressive localized cancers, such as squamous cell carcinoma of the oral cavity.Keywords: functionalized nanomaterial, natural ligand, nanoparticle targeting, squamous carcinoma, globotriaosylceramide

A theoretical description of the sunbird, a drinking bird without any external liquid, is compared with experiment. The transient times and the periods of oscillation given by a simulation of the dynamics agree with the measured values.

We present a simple model of the dynamics of the drinking bird and relate its period to the properties of its internal and external liquids. The effect of humidity on the motion is studied and it is shown that there are two evaporation regimes. The results of the model are in agreement with observations.

We have investigated the crystal structure of Cs2CuCl4 in the 0-20 GPa range as a function of pressure and how pressure affects its electronic properties by means of optical absorption spectroscopy. In particular, we focused on the electronic properties in the low-pressure Pnma phase, which are mainly related to the tetrahedral CuCl2- 4 units distorted by the Jahn-Teller effect. This study provides a complete characterization of the electronic structure of Cs2CuCl4 in the Pmna phase as a function of the cell volume and the Cu-Cl bond length, RCu-Cl. Interestingly, the opposite shift of the charge-transfer band-gap and the Cu2+ d-d crystal-field band shift with pressure are responsible for the strong piezochromism of Cs2CuCl4. We have also explored the high-pressure structure of Cs2CuCl4 above 4.9 GPa yielding structural transformations that are probably associated with a change of coordination around Cu2+. Since the high-pressure phase appears largely amorphized, any structural information from X-ray diffraction is ruled out. We use electronic probes to get structural information of the high-pressure phase. [ABSTRACT FROM AUTHOR]

This work presents the structural, morphological, and luminescent characterization of pure SrTiO3 and SrTiO3:Eu3+ powders doped with different europium atomic concentrations from 3.0 to 7.0 a.t.%. Those phosphors were prepared by pressure-assisted combustion synthesis using titanium oxide as precursor and were subjected to postannealing at 1200°C. XRD measurements indicated that undoped and Eu3+ doped samples presented a single cubic crystalline phase and SEM images demonstrated that we have particles with sizes in the range of 0.2 µm–1.0 µm. Moreover, the size of the grains increases as the content of Eu3+ dopant increases. A strong red emission from Eu3+ ions was obtained by photoluminescence under excitation at 396 nm and confirmed by cathodoluminescence. All those results indicate that our red phosphors could be useful for potential applications in solid state lighting and field emission displays. [ABSTRACT FROM AUTHOR]

The structural and spectroscopic properties of (Eu 1- x Yb x) 2 O 3 nanocrystals with cubic (C-type) and monoclinic (B-type) crystalline structures have been studied. NCs have been synthetized by the sol-gel Pechini method and characterized at room temperature by X-ray diffraction, transmission electron microscopy, diffuse reflectance, Raman spectroscopy and photoluminescence techniques. NIR emission from Yb3+ ions has been observed in both C- and B-type NCs upon excitation of Eu3+ ions at 532 nm, where Yb3+ ions do not absorb photons. This fact reveals that an efficient non-resonant energy transfer process from Eu3+ to Yb3+ takes place, allowing to obtain simultaneous visible and NIR emissions under visible excitation. The decay curves of the 5D 0 → 7F 2 Eu3+ emission of C-type NCs corroborate this phenomenon since the Eu3+ lifetime has been found to decrease as the Yb3+ content increases. Finally, we discuss the use of the Eu3+ luminescence as a structural probe to distinguish between different RE 2 O 3 polymorphs. • (Eu 1-x Yb x) 2 O 3 nanocrystals have been stabilized within the cubic (C-type) and monoclinic (B-type) structures by the sol-gel Pechini method. • An efficient non-resonant energy transfer process from Eu3+ to Yb3+ takes place, inducing simultaneous Vis-NIR emission under Vis excitation. • Eu3+ lifetime has been found to decrease when increasing the Yb3+ content, contrary to the usual behavior. • Eu3+ luminescence is proposed as a structural probe to differentiate between RE 2 O 3 polymorphs. [ABSTRACT FROM AUTHOR]

Reproducibility of computational research is often challenging despite established guidelines and best practices. Translating these guidelines into practical applications remains difficult. Here, we present ENCORE, an approach to enhance transparency and reproducibility by guiding researchers in how to structure and document a computational project. ENCORE builds on previous efforts in computational reproducibility and integrates all project components into a standardized file system structure. It utilizes pre-defined files as documentation templates, leverages GitHub for software versioning, and includes an HTML-based navigator. ENCORE is designed to be agnostic to the type of computational project, data, programming language, and ICT infrastructure, and does not rely on specific software tools. We also share our group's experience using ENCORE, highlighting that the most significant challenge to the routine adoption of approaches like ours is the lack of incentives to motivate researchers to dedicate sufficient time and effort to ensure reproducibility., (© 2024. The Author(s).)

Optical fiber with YPO 4 :Pr 3+ nanocrystals (NCs) is presented for the first time using the glass powder-NCs doping method. The method's advantage is separate preparation of NCs and glass to preserve luminescent and optical properties of NCs once they are incorporated into optical fiber. The YPO 4 :Pr 3+ nanocrystals were synthesized by the co-precipitation and hydrothermal methods, optimized for size (< 100 nm), shape, Pr 3+ ions concentration (0.2 mol%), and emission lifetime. The core glass was selected from the non-silica P 2 O 5 -containing system with refractive index (n = 1.788) close to the NCs (n o  = 1.657, n e  = 1.838). Optical fiber was drawn by modified powder-in-tube method after pre-sintering of glass powder-YPO 4 :Pr 3+ (wt 3%) mixture to form optical fiber preform. Luminescent properties of YPO 4 :Pr 3+ and optical fiber showed their excellent agreement, including sharp Pr 3+ emission at 600 nm ( 1 D 2 - 3 H 4 ) and 1 D 2 level lifetime (τ = 156 ± 5 µs) under 488 nm excitation. The distribution of the YPO 4 :Pr 3+ NCs in optical fiber were analyzed by TEM-EDS in the core region (FIB-SEM-prepared). The successful usage of glass powder-NCs doping method was discussed in the aspect of promising properties of the first YPO 4 :Pr 3+ doped optical fiber as a new way to develop active materials for lasing applications, among others., (© 2024. The Author(s).)

Objective: This study aims to describe the accessibility to and promotion of alcohol and tobacco around secondary schools in Madrid and its distribution in relation with area-level socioeconomic deprivation; analyze the relationship between this exposure and individual consumption characteristics of students between 14 and 18 years old; and explore other facilitators of this consumption., Method: Mixed-methods study conducted in three phases: 1) we collected data on accessibility to and promotion of alcohol and tobacco in the environment using systematic social observation around 55 secondary schools; 2) we administered 2287 questionnaires among the students in these centers to gather information about characteristics and determinants of consumption; and 3) we conducted 20 semi-structured interviews and one discussion group to deepen in the results obtained in surveys and systematic social observation. We will use Geographic Information Systems to integrate and analyze the data from a spatial perspective., (Copyright © 2023 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.)

Measuring the density of alcohol outlets around schools is a critical step towards understanding the drivers of drinking among adolescents. Different methodologies have been used in the literature for this purpose, but the implications of using one methodology or another have not been clearly assessed. Our aim was to compare different methods to measure alcohol outlet density and highlight under which characteristics of the environment might be best using each approach. We used Geographic Information Systems to geolocate schools (n = 576) and alcohol outlets (n = 21,732) in Madrid. We defined the density of alcohol outlets as the number of establishments within an area of 400 m around schools measured using two buffering methods: crow flies' and street network distances. We evaluated the agreement between both methods visually and through regression models, including street connectivity, population density, and density of recreational venues as predictors of disagreement. The density of alcohol outlets around schools was higher using crow flies' distances compared to street network distances. The differences between methodologies were wider in areas of higher density of outlets, especially in the downtown areas, where there are higher population density and street connectivity. Our results suggest that the spatial characteristics and morphology of the study area (e.g., street connectivity and population density) should be considered when deciding the methodology to be used to measure alcohol outlet density. Future studies should explore the implications of different exposure measures in their association with drinking prevalence and consumption patterns among different geographical contexts., (© 2023. The Author(s).)

Sequencing of B-cell and T-cell immune receptor repertoires helps us to understand the adaptive immune response, although it only provides information about the clonotypes (lineages) and their frequencies and not about, for example, their affinity or antigen (Ag) specificity. To further characterize the identified clones, usually with special attention to the particularly abundant ones (dominant), additional time-consuming or expensive experiments are generally required. Here, we present an extension of a multiscale model of the germinal center (GC) that we previously developed to gain more insight in B-cell repertoires. We compare the extent that these simulated repertoires deviate from experimental repertoires established from single GCs, blood, or tissue. Our simulations show that there is a limited correlation between clonal abundance and affinity and that there is large affinity variability among same-ancestor (same-clone) subclones. Our simulations suggest that low-abundance clones and subclones, might also be of interest since they may have high affinity for the Ag. We show that the fraction of plasma cells (PCs) with high B-cell receptor (BcR) mRNA content in the GC does not significantly affect the number of dominant clones derived from single GCs by sequencing BcR mRNAs. Results from these simulations guide data interpretation and the design of follow-up experiments., (© 2023. The Author(s).)