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Tm3+-singly-doped and Tm3+-/Ho3+-codoped TeO2-Bi2O3-ZnO-Li2O-Nb2O5 ( TBZLN) tellurite glasses were successfully prepared by the melt-quenching technique. Emission characteristics and energy transfer mechanisms were studied upon 785-nm laser diode excitation. A significant enhancement of emission intensity at 1.81 μm with increasing concentration of Tm3+ ions has been observed while increase in the emission intensity at 2.0 μm with increasing concentration of Ho3+ has been observed up to the equal concentration of Tm3+ (0.5 mol%) in TBZLN glasses. The stimulated emission cross section of Tm3+: 3F4→3H6 (5.20×10−21 cm2) and Ho3+: 5I7→5I8 (4.00×10−21 cm2) in 1.0 mol% Tm3+-doped and 0.5 mol% Tm3+/1.0 mol% Ho3+-codoped TBZLN glasses are higher compared with the reported and are found to be excellent candidates for solid-state lasers operating at ~1.8 and 2.0 μm, respectively. The extension of near-infrared ( NIR) emission of Tm3+ with Ho3+ ions provides the possibility of using these materials for broadband NIR amplifiers. [ABSTRACT FROM AUTHOR]

We perform fully relativistic band-structure calculations for cubic SrTiO[sub 3], which are used to obtain carrier effective masses and the frequency behavior of its complex dielectric function ∈(ω). The obtained values and anisotropy of the carrier effective masses are shown to be highly influenced by the relativistic contributions. In order to evaluate the static dielectric constant, the low-frequency behavior of ∈(ω) is obtained by taking into account also the optical phonon contributions to the imaginary part of ∈(ω), adopting a simplified classical oscillator dispersion model. It is found that the phonon contribution leads to about 240 times (at T = 85 K) the value of the bare electronic contribution to the dielectric constant. The calculated temperature dependence of the dielectric constant is shown to be consistent with that observed in bulk SrTiO[sub 3] static permittivity measurements. [ABSTRACT FROM AUTHOR]

In this paper, we present results on time visible emission from Er3+-doped amorphous SiN thin films as a function of temperature. It is shown that the measured lifetime of the green emission decreases as the temperature increases and the effect is mainly attributed to thermalization of the 2H11/2 and 4S3/2 Er3+ levels. [Copyright &y& Elsevier]

Introduction: Pain in inflammatory myelopathies is frequent but has not been clinically characterized. It is an appropriate model to assess pain mechanisms after spinal cord inflammatory lesions since there are no brain lesions that could bias pain assessment, cognition and mood assessment. It has been suggested that the prevalence and severity of pain syndromes among patients with neuromyelitis optica (NMO) and longitudinally extensive transverse myelitis (LETM) are greater in comparison to those with multiple sclerosis. It is not clear whether higher scores on the Expanded Disability Status Scale (EDSS) could influence pain and health-related quality of life scores. This study aimed to characterize disability, pain syndromes, and quality of life in this population. Materials and Methods: Patients with spinal cord-restricted demyelinating disease (last relapse at least 12 months prior to evaluation) and complaint of pain underwent a full physical examination and filled out a DN-4 questionnaire, Brief Pain Inventory (BPI), Neuropathic Pain Symptom Inventory (NPSI), McGill Pain Questionnaire (MPQ) and SF-12 Health Survey. Disability was assessed using the EDSS. Spasticity was measured using the Ashworth Scale. Patients were classified as at-level and below-level pain. Results: Twenty patients were included (15 female, 45.3±9.8 yr).Twelve (60%) were diagnosed as NMO, the remaining as LETM. At-level pain was present in 9 (45%) and below-level in 10 (50%). Thirteen (65%) patients had more than one pain syndrome. Results refer to the main pain syndrome. The median scores of the BPI (VAS) was 21.9±7.2; BPI interference 24.9±15.3; Mental Component Summary Scale of the SF12 49.5 ± 10.7; Physical Component Summary 33.0±10.3; NPSI 23.3±15.4; and MPQ 8.5±2.5. The median EDSS was 4.8±2.4 and Ashworth spasticity scale 1.35±1.1. The DN4 detected neuropathic pain (NeP) in 18 patients. Low back pain was a major pain complaint in 6 (30%) patients. Discussion and Conclusion: NeP is frequent in patients with inflammatory myelopathies. Low back pain was noted as the main pain syndrome in a significant proportion of patients. Mixed pain syndromes are the rule in these patients. [ABSTRACT FROM AUTHOR]

Highlights: [•] The formation of CdS nanocrystals in the glassy host is shown by Raman measurements. [•] Nd2O3 modifies the growth of CdS nanocrystals in the SNAB glass. [•] Nd3+ ions are not incorporated inside the semiconductor nanocrystals. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the optical characterization of Nd3+ ions in nanostructured SiO2–Na2CO3–Al2O3–B2O3 (SNAB) CdS glass, synthesized by fusion. Radiative properties of the glass were determined by absorption, luminescence spectroscopy and lifetime measurements. Nd3+ emission enhancement and quenching were investigated in the presence of CdS nanocrystals. Nd3+-emission quenching was attributed to upconversion mechanisms and nonradiative processes such as multiphonon decay and energy transfer, while the Nd3+-emission enhancement was due to energy transfer from the CdS nanocrystals. Changes in the chemical environment around CdS nanocrystals were also confirmed by Judd–Ofelt calculations. [Copyright &y& Elsevier]

Highlights: [•] UV transparent glass matrix is used for rare earth doping at high concentrations. [•] Cluster formation of Yb3+ was not observed as well as, no evidence of cooperative luminescence among Yb3+. [•] An optimized near infrared emitter material (920 to 1060nm) is obtained. [•] Relatively high figure of merit was found. [Copyright &y& Elsevier]

Abstract: The present work reports on the thermo-optical study of germanate thin films doped with Au and Ag nanoparticles. Transmission Electron Microscopy images, UV–visible absorption and Micro-Raman scattering evidenced the presence of nanoparticles and the formation of collective excitations, the so called surface plasmons. Moreover, the effects of the metallic nanoparticles in the thermal properties of the films were observed. The thermal lens technique was proposed to evaluate the Thermal Diffusivity (D) of the samples. It furnishes superficial spatial resolution of about 100μm, so it is appropriate to study inhomogeneous samples. It is shown that D may change up to a factor 3 over the surface of a film because of the differences in the nanoparticles concentration distribution. [Copyright &y& Elsevier]

Abstract: This paper presents the optical characteristics of Nd3+ silicate glass (SiO2–B2O3–PbO), synthesized by the fusion method. Two sets of samples were prepared: glass and corresponding glass ceramics. Optical absorption, luminescence, Raman spectroscopy and atomic force microscopy (AFM) measurements were performed in order to determine the structural properties of the systems and the radiative characteristics of Nd3+ ions. Near infrared luminescence exhibited typical Nd3+ bands. Raman and AFM measurements indicated nanocrystal growth with thermal treatment of the glass ceramics. Judd–Ofelt calculations also confirmed that heat treatment induced structural rearrangement of the samples that was dependent on Nd2O3 concentration. This resulted in changes in the optical and physical properties of the samples, including stimulated emission cross section and rigidity. [Copyright &y& Elsevier]

Introducción: Los cambios en el estilo de vida y el uso de nuevas tecnologías han hecho que niños y adolescentes sean más sedentarios. La actividad física puede mejorar una serie de aspectos del rendimiento mental. Algunos estudios también han demostrado asociaciones entre el tiempo delante de la televisión y una peor salud mental. Material y métodos: En el presente estudio se presentan resultados de los hijos de 94 mujeres embarazadas sanas participantes en el estudio NUHEAL que fueron suplementadas de forma aleatoria desde la semana 20 de gestación y hasta el parto, con 500 mg de DHA+150 mg de EPA, o 400 mg de 5-MTHF, ambos o placebo. La actividad física se midió utilizando PAQ-C, FELS y un cuestionario de Actividades Sedentarias en los hijos a los 7.5 años. Los trastornos del comportamiento se estudiaron en los niños mediante el test Child Behaviour Check List (CBCL). Resultados: No se demostraron diferencias estadísticas ni en el grado de sedentarismo, ni en el número de niños que presentaron problemas de comportamiento entre los 4 grupos de estudio. No hubo diferencias significativas respecto a la internalización de problemas según el nivel de actividad física medida tanto por el PAQ-C como por el FELS. Los niños que mostraron alteraciones del comportamiento de tipo externalizante (comportamiento de ruptura de reglas y conducta agresiva) presentaban puntuaciones más bajas de actividad física en el PAQ-C (P = 0,035). Conclusión: La actividad física puede tener un efecto positivo para el tratamiento de los problemas de comportamiento en los niños, y específicamente en los de externalización. [ABSTRACT FROM AUTHOR]

Introduction: Adiponectin replacement therapy shows promising outcomes in various diseases, especially for bone-related disorders. Challenges in using the complete protein have led to alternative approaches, with AdipoRon and AdipoAI emerging as extensively researched drug candidates. Their influence on models of bone-related disorders has progressed considerably but there has been no review of their effectiveness in modulating bone metabolism and repair., Method: This systematic review seeks to address this knowledge gap. Based on preclinical evidence from PubMed, EMBASE, and COCHRANE, ten studies were included following PRISMA guidelines. The JBI Checklist Critical Appraisal Tool assessed the quality of this systematic review. The studies encompassed various animal models, addressing bone defects, osseointegration, diabetes-associated periodontitis, fracture repair, growth retardation, and diabetes-associated peri-implantitis., Result: AdipoRon and AdipoAI demonstrated effectiveness in modulating bone metabolism and repair through diverse pathways, including the activation of AdipoR1/APPL1, inhibition of F-actin ring formation, suppression of IκB-α phosphorylation, p65 nuclear translocation and Wnt5a-Ror2 signaling pathway, reduction of CCL2 secretion and expression, regulation of autophagy via LC3A/B expression, modulation of SDF-1 production, activation of the ERK-1/2 signaling pathway, modulation of bone integration-related markers and osteokines such as RANKL, BMP-2, OPG, OPN, and Runx2, inhibition of RANKL in osteoblasts, and inhibition of podosome formation via the activation of AMPK., Conclusion: While preclinical studies show promise, human trials are crucial to confirm the clinical safety and effectiveness of AdipoRon and AdipoAI. Caution is necessary due to potential off-target effects, especially in bone therapy with multi-target approaches. Structural biology and computational methods can help predict and understand these effects., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

In this paper, thermally stable lead-bismuth-borate glasses were doped with 0.5 mol% of Pr 3+ ions at several concentration levels of Yb 3+ ions. Structural characterizations were performed via Raman, differential scanning calorimetry, optical absorption and fluorescence spectra. The Judd-Ofelt intensity parameter, [Formula: see text], of Pr 3+ doped glass was comparatively higher than those from reported ones, which reflects the increase of co-valency and asymmetry of chemical bonds in the local environment of Pr 3+ . Near-infrared emission in 900-2200 nm wavelength range was recorded through 443 nm blue laser pumping. Visible to near-IR quantum cutting and concentration quenching mechanisms were discussed to understand the luminescent behaviour. Intense IR emission ([Formula: see text] features generated by absorbing one visible photon leads to quantum efficiencies close to 128% in Pr 3+ /Yb 3+ co-doped samples which may improve the solar spectrum absorption and accordingly, increase the efficiency of c-Si solar cells. Emission cross-section, lifetime, figure of merit and gain bandwidth corresponding to Pr 3+ : [Formula: see text] ([Formula: see text]m) were comparatively reported suggesting that the glass with molar composition 0.5Pr 3+ /0.1Yb 3+ might be a potential candidate for [Formula: see text]m laser operation with low pump threshold., (© 2022. The Author(s).)

The present work was proposal the potential evaluation of Fourier-Transform Mid-Infrared (FT-MIR) associated with chemometric approach in green beans, in order to discriminate the origin of special Arabica coffees in a single state that has heterogeneous environments. Partial Least Squares Discriminant Analysis (PLS-DA) model presented as result: 3 latent variables, R 2 X (cum) = 0.892, R 2 Y (cum) = 0.659; Q 2 Y (cum) = 0.494, RMSEP = 0.182387, p-value CV-Anova = 0.009, 100% of both sensitivity and specificity and the prediction classification obtained was: 100, 83.33, 100, 83.33% for class 1, class 2, class 3 and class 4, respectively. These results can be considered adequate for the proposed hypothesis. The obtained results that the regions have markers such as trigonelline, chlorogenic and fatty acids, sensitive to absorption in the mid-infrared and that are able to determine the origin of green coffee beans of Arabica. Thus, the FT-MIR associated with chemometrics has the potential to employ speed, modernity and cost reduction in the certification of origin of coffees., Competing Interests: Maria Jose Valenzuela Bell reports financial support was provided by 10.13039/501100003593National Council for Scientific and Technological Development. Maria Jose Valenzuela Bell reports financial support was provided by Minas Gerais State Foundation of Support to the Research., (© 2022 The Authors.)

Europium oxide (Eu 2 O 3 ) was used to evaluate the affinity of this rare earth element for interacting with double-stranded (ds) DNA molecules. To perform the study, we used single molecule force spectroscopy with optical tweezers and gel electrophoresis assays. Force spectroscopy experiments show that Eu 2 O 3 presents a strong interaction with dsDNA, and the binding is independent on the ionic strength used in the surrounding environment. Among the main characteristics of the interaction, Eu 2 O 3 tends to bind in a cooperative way, forming bound clusters of ∼ 3 molecules, and presents a high equilibrium association binding constant on the order of 10 5  M -1 . In addition, gel electrophoresis confirm the weak electrostatic character of the interaction and explicit show that Eu 2 O 3 does not interfere on drug intercalation into the double-helix. Such results demonstrate the potential of europium for interacting with nucleic acids and strongly suggest that this rare earth element may be considered for the design of new metal-based anticancer drugs in the future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Bioemulsifiers are surface active compounds which could be potentially used in food processing, cosmetic sector and oil recovery. Sugarcane straw (SS), was used as the raw substrate for the production of bio-emulsifiers (BE) by Cutaneotrichosporon mucoides. Three different delignification strategies using dilute sodium hydroxide, sodium sulfite and ammonium hydroxide followed by enzymatic hydrolysis (Cellic CTec 2, 7.5% total solids, 15 FPU/g, 72 h) were studied. Enzyme hydrolysis of ammonium hydroxide pretreated SS showed a maximum of 62.19 ± 0.74 g/l total reducing sugars with 88.35% hydrolytic efficiency (HE) followed by sodium hydroxide (60.06 ± 0.33 g/l; 85.40% HE) and sodium sulfite pretreated SS (57.22 ± 0.52 g/l; 84.71% HE), respectively. The ultrastructure of SS (native and delignified) by fourier transform-infrared and near infrared spectroscopy, revealed notable structural differences. The fermentation of hydrolysates by C. mucoides into bioemulsifiers showing emulsification index (EI) of 54.33%, 48.66% and 32.66% from sodium sulfite, sodium hydroxide, and ammonium hydroxide pretreated SS, respectively., Competing Interests: Conflict of interest The authors declare no conflict of interest., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Of the three RAS oncoproteins, only HRAS is delocalized and inactivated by farnesyltransferase inhibitors (FTI), an approach yet to be exploited clinically. In this study, we treat mice bearing Hras-driven poorly differentiated and anaplastic thyroid cancers ( Tpo-Cre/Hras G12V /p53 flox/flox ) with the FTI tipifarnib. Treatment caused sustained tumor regression and increased survival; however, early and late resistance was observed. Adaptive reactivation of RAS-MAPK signaling was abrogated in vitro by selective RTK (i.e., EGFR, FGFR) inhibitors, but responses were ineffective in vivo , whereas combination of tipifarnib with the MEK inhibitor AZD6244 improved outcomes. A subset of tumor-bearing mice treated with tipifarnib developed acquired resistance. Whole-exome sequencing of resistant tumors identified a Nf1 nonsense mutation and an activating mutation in Gnas at high allelic frequency, supporting the on-target effects of the drug. Cell lines modified with these genetic lesions recapitulated tipifarnib resistance in vivo This study demonstrates the feasibility of targeting Ras membrane association in cancers in vivo and predicts combination therapies that confer additional benefit. Significance: Tipifarnib effectively inhibits oncogenic HRAS-driven tumorigenesis and abrogating adaptive signaling improves responses. NF1 and GNAS mutations drive acquired resistance to Hras inhibition, supporting the on-target effects of the drug. Cancer Res; 78(16); 4642-57. ©2018 AACR ., (©2018 American Association for Cancer Research.)

Milk powder is an international dairy commodity. Goat and cow milk powders are significant sources of nutrients and the investigation of the authenticity and classification of milk powder is particularly important. The use of time-resolved fluorescence techniques to distinguish chemical composition and structure modifications could assist develop a portable and non-destructive methodology to perform milk powder classification and determine composition. This study goal is to differentiate milk powder samples from cows and goats using fluorescence lifetimes. The samples were excited at 315nm and the fluorescence intensity decay registered at 468nm. We observed fluorescence lifetimes of 1.5±0.3, 6.4±0.4 and 18.7±2.5ns for goat milk powder; and 1.7±0.3, 6.9±0.2 and 29.9±1.6ns for cow's milk powder. We discriminate goat and cow powder milk by analysis of variance using Fisher's method. In addition, we employed quadratic discriminant analysis to differentiate the milk samples with accuracy of 100%. Our results suggest that time-resolved fluorescence can provide a new method to the analysis of powder milk and its composition., (Copyright © 2016 Elsevier B.V. All rights reserved.)

17 α -Ethinyl estradiol (EE2), which is used worldwide in the treatment of some cancers and as a contraceptive, is often found in aquatic systems and is considered a pharmaceutically active compound (PhACs) in the environment. Current methods for the determination of this compound, such as chromatography, are expensive and lengthy and require large amounts of toxic organic solvents. In this work, a voltammetric procedure is developed and validated as a screening tool for detecting EE2 in water samples without prior extraction, clean-up, or derivatization steps. Application of the method we elaborate here to EE2 analysis is unprecedented. EE2 detection was carried out using differential pulse adsorptive cathodic stripping voltammetry (DP AdCSV) with a hanging mercury drop electrode (HMDE) in pH 7.0 Britton-Robinson buffer. The electrochemical process of EE2 reduction was investigated by cyclic voltammetry at different scan rates. Electroreduction of the hormone on a mercury electrode exhibited a peak at -1.16 ± 0.02 V versus Ag/AgCl. The experimental parameters were as follows: -0.7 V accumulation potential, 150 s accumulation time, and 60 mV s -1 scan rate. The limit of detection was 0.49  μ g L -1 for a preconcentration time of 150 s. Relative standard deviations were less than 13%. The method was applied to the detection of EE2 in water samples with recoveries ranging from 93.7 to 102.5%., Competing Interests: The authors report no conflict of interests.