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1.
Am J Respir Crit Care Med ; 210(3): 311-317, 2024 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-38358858

RESUMEN

Due to a typesetter error, this is a previous version of this article; It will be replaced shortly by the final accepted version. Rationale: Organizing ICU interprofessional teams-nurses, physicians, and respiratory therapists-is high priority because of workforce crises, but how often clinicians work together (i.e., interprofessional familiarity) remains unexplored. Objectives: Determine if mechanically ventilated patients cared for by teams with greater familiarity have lower mortality, shorter duration of mechanical ventilation, and greater spontaneous breathing trial (SBT) implementation. Methods: Using electronic health records from five ICUs (2018-2019), we identified the interprofessional team that cared for each mechanically ventilated patient each shift, calculated familiarity, and modeled familiarity exposures separately on ICU mortality, duration of mechanical ventilation, and SBT implementation using encounter-level generalized linear regression models with a log-link, unit-level fixed effects adjusting for cofounders, including severity of illness. Measurements and Main Results: Familiarity was defined as how often clinicians worked together for all patients in an ICU (i.e., coreness) and for each patient (i.e., mean team value). Among 4,292 patients (4,485 encounters, 72,210 shifts), unadjusted mortality was 12.9%, average duration of mechanical ventilation was 2.32 days, and SBT implementation was 89%. An increase in coreness and mean team value, by the SD of each, was associated with lower probability of dying (coreness: adjusted marginal effect, -0.038; 95% confidence interval [-0.07 to -0.004]; mean team value: adjusted marginal effect, -0.0034 [-0.054 to -0.014]); greater probability of receiving SBT when eligible (coreness: 0.45 [0.007 to 0.083]; mean team value: 0.012 [-0.017 to 0.042]), and shorter duration of mechanical ventilation (coreness: -0.23 [-0.321 to -0.139]). Conclusions: Interprofessional familiarity was associated with improved outcomes; assignment models that prioritize familiarity might be a novel solution.


Asunto(s)
Unidades de Cuidados Intensivos , Grupo de Atención al Paciente , Respiración Artificial , Humanos , Respiración Artificial/estadística & datos numéricos , Masculino , Femenino , Persona de Mediana Edad , Unidades de Cuidados Intensivos/estadística & datos numéricos , Anciano , Mortalidad Hospitalaria , Adulto
2.
Phys Rev Lett ; 132(14): 141401, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38640366

RESUMEN

The intrinsic presence of ghosts in the symmetric teleparallel framework is elucidated. We illustrate our general arguments in f(Q) theories by studying perturbations in the three inequivalent spatially flat cosmologies. Two of these branches exhibit reduced linear spectra, signalling they are infinitely strongly coupled. For the remaining branch we unveil the presence of seven gravitational degrees of freedom and show that at least one of them is a ghost. Our results rule out f(Q) cosmologies and clarify the number of propagating degrees of freedom in these theories.

3.
Int Microbiol ; 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38512524

RESUMEN

AIM: Volatile organic compounds (VOCs) are being studied as potential biomarkers in many infections. Therefore, this study aimed to analyze the volatile profile of three Gram-positive bacteria of clinical relevance to identify potential volatile biomarkers that allow their differentiation. METHODS AND RESULTS: L. monocytogenes, S. aureus, and E. faecalis clinical isolates were inoculated in a thioglycollate medium until grown. Then, VOCs were extracted by solid-phase microextraction, and the data obtained were subjected to multivariate analysis. According to our results, there was a high production of aldehydes in E. faecalis. In the case of alcohols, they only increased in L. monocytogenes, while ketones were produced significantly in all three bacteria, mainly due to acetoin. Acids were produced significantly in E. faecalis and L. monocytogenes. CONCLUSIONS: Potential biomarkers of L. monocytogenes could be 1-butanol and 2-methylbutanoic acid. In the case of E. faecalis, the VOC most related to its presence was nonanal. Lastly, potential biomarkers of S. aureus could be isoamyl butanoate and methionol, although some pyrazines have also been associated with this bacterium. SIGNIFICANCE AND IMPACT OF THE STUDY: The identification of potential biomarkers of these clinically relevant bacteria could open the way for the diagnosis of these infections through the analysis of volatile compounds.

4.
J Intensive Care Med ; : 8850666241253202, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38715423

RESUMEN

OBJECTIVE: Patients with acute myocardial infarction (AMI) complicated by respiratory failure require antiplatelet regimens which often cannot be stopped and may increase bleeding from tracheostomy. However, there is limited available data on both the proportion of patients undergoing tracheostomy and the impact on antiplatelet regimens on outcomes. METHODS: Utilizing the Vizient® Clinical Data Base, we identified patients ≥18 years admitted from 2015 to 2019 with a primary diagnosis of AMI and requiring invasive mechanical ventilation (IMV). We assessed for the incidence of patients undergoing tracheostomy, outcomes stratified by the timing of tracheostomy (≤10 vs >10 days), and the association between dual antiplatelet therapy (DAPT) use and in-hospital mortality. RESULTS: We identified 26 435 patients presenting with AMI requiring IMV. The mean (SD) age was 66.8 (12.3) years and 33.4% were women. The incidence of tracheostomy was 6.0% (n = 1573), and the median IMV time to tracheostomy was 12 days, 55.6% of which underwent percutaneous and 44.4% underwent open tracheostomy. Over 90% (n = 1424) underwent tracheostomy (>10 days) and had a similar mortality when compared to early (≤10 days) tracheostomy (22.5% vs 22.8%, P = 0.94). On the day of tracheostomy, only 24.7% were given DAPT, which was associated with a lower mortality than those not on DAPT (17.4% vs 23.7%, P = 0.01). After multivariable adjustment, DAPT use on the day of tracheostomy remained associated with lower in-hospital mortality (odds ratio 0.68; 95% confidence interval: 0.49-0.94, P = 0.02). Tracheostomy complications were not different between groups (P > 0.05), but more patients in the DAPT group required post-tracheostomy blood transfusions (5.6% vs 2.7%, P = 0.01). CONCLUSION: Approximately 1 in 20 intubated AMI patients requires tracheostomy. The lack of DAPT interruption on the day of tracheostomy but not the timing of tracheostomy was associated with a lower in-hospital mortality. Our results suggest that DAPT should not be a barrier to tracheostomy for patients with AMI.

5.
Appl Microbiol Biotechnol ; 108(1): 258, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38466440

RESUMEN

Environmental concerns about residues and the traditional disposal methods are driving the search for more environmentally conscious processes, such as pyrolysis and gasification. Their main final product is synthesis gas (syngas) composed of CO, CO2, H2, and methane. Syngas can be converted into various products using CO-tolerant microorganisms. Among them, Rhodospirillum rubrum is highlighted for its biotechnological potential. However, the extent to which high doses of CO affect its physiology is still opaque. For this reason, we have studied R. rubrum behavior under high levels of this gas (up to 2.5 bar), revealing a profound dependence on the presence or absence of light. In darkness, the key variable affected was the lag phase, where the highest levels of CO retarded growth to more than 20 days. Under light, R. rubrum ability to convert CO into CO2 and H2 depended on the presence of an additional carbon source, such as acetate. In those conditions where CO was completely exhausted, CO2 fixation was unblocked, leading to a diauxic growth. To enhance R. rubrum tolerance to CO in darkness, a UV-accelerated adaptive laboratory evolution (UVa-ALE) trial was conducted to isolate clones with shorter lag phases, resulting in the isolation of clones 1.4-2B and 1.7-2A. The adaptation of 1.4-2B was mainly based on mutated enzymes with a metabolic function, while 1.7-3A was mostly affected at regulatory genes, including the anti-repressor PpaA/AerR. Despite these mutations having slight effects on biomass and pigment levels, they successfully provoked a significant reduction in the lag phase (-50%). KEYPOINTS: • CO affects principally R. rubrum lag phase (darkness) and growth rate (light) • CO is converted to CO2/H2 during acetate uptake and inhibits CO2 fixation (light) • UVa-ALE clones showed a 50% reduction in the lag phase (darkness).


Asunto(s)
Monóxido de Carbono , Rhodospirillum rubrum , Monóxido de Carbono/metabolismo , Rhodospirillum rubrum/genética , Rhodospirillum rubrum/metabolismo , Dióxido de Carbono/metabolismo , Acetatos/metabolismo
6.
J Clin Densitom ; 27(1): 101461, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38134510

RESUMEN

BACKGROUND: Dual-energy X-ray absorptiometry (DXA) measures are affected by the noise produced by external factors such as textile compression found in loose clothing. The study aimed to determine the effect of a compression bandage (CB) on body composition (BC) assessed by DXA. METHODS: Sixty volunteers (age=21.4±4.7yr.) underwent full-body DXA scans on a control (CTRL) condition and after wearing a 30-mmHg CB on the trunk, legs, and arms. ANOVA (2 genders by 2 experimental conditions) determined mean interactions in BC variables tissue body fat% (BF%), region body fat% (RBF%), body tissue (BT), fat mass (FM), lean mass (LM), bone mineral content (BMC), and total mass (TM). Absolute reliability in BC scores was studied by the typical error of the measurement (TEM), the coefficient of variability (CV), and Bland-Altman plots. RESULTS: ANOVA interactions were found on tissue total BF% (p=0.049), RBF% (p=0.048), android lean mass (p=0.004), and android total mass (p=0.019). The CV was small for tissue BF% (2.61±0.93%, CI95%=0.79, 4.43%), RBF% (2.66±1.78%, CI95%=-0.83, 6.15%), BT (4.82±2.19%, CI95%=0.54, 9.10kg), FM (4.17±2.25%, CI95%=-0.24, 8.58kg), LM (3.25±2.44%, CI95%=-1.53, 8.04kg), BMC (4.81±2.96%, CI95%=-0.99, 10.62kg), and TM (2.84±2.80%, CI95%=-2.65, 8.33kg). Bland-Altman plots showed random error for BF%, LM, and BMC. A bias of 0.5% was observed on BF% in males. CONCLUSION: A CB worn during a full-body DXA scan elicited similar BC scores than not wearing it. The variation in scores was <10% for most BC variables, and a trivial bias of 0.5% in BF% was detected in male scores.


Asunto(s)
Tejido Adiposo , Composición Corporal , Masculino , Humanos , Femenino , Adolescente , Adulto Joven , Adulto , Absorciometría de Fotón , Reproducibilidad de los Resultados , Densidad Ósea
7.
J Sports Sci ; 42(3): 255-262, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38451829

RESUMEN

We studied the effect of exercise-induced body fluid redistribution on dual-energy x-ray absorptiometry (DXA) body composition scores. Thirty males completed 30-min of upper-body exercise (UBE), lower-body exercise, and seated non-exercise control (NEC). ANOVA determined interactions between experimental conditions and measurements on body composition variables. For UBE, mean pre to post differences were found on tissue fat (M = 0.35 ± 0.12%; CI95%diff = 0.10 to 0.59%; p = 0.007), region fat (M = 0.32 ± 0.11%; CI95%diff = 0.09 to 0.55%; p = 0.008), lean mass (M = 0.27 ± 0.01 kg; CI95%diff = 0.18 to 0.37 kg; p ≤ 0.0001), and total mass (M = 0.27 ± 0.05 kg; CI95%diff = 0.17 to 0.36 kg; p ≤ 0.0001). Mean tissue pre to post differences were found for the total body in the NEC (M = 0.10 ± 0.04 kg; CI95%diff = 0.03 to 0.18 kg; p = 0.008), UBE (M = 0.19 ± 0.03 kg; CI95%diff = 0.14 to 0.24 kg; p ≤ 0.0001), and LBE (M = 0.31 ± 0.04 kg; CI95%diff = 0.24 to 0.39 kg; p ≤ 0.0001) conditions. High absolute reliability was found within experimental conditions. These findings have practical implications for technicians, since acute exercise elicited small changes in body composition scores using DXA.


Asunto(s)
Absorciometría de Fotón , Composición Corporal , Ejercicio Físico , Humanos , Masculino , Ejercicio Físico/fisiología , Composición Corporal/fisiología , Adulto Joven , Adulto , Líquidos Corporales/fisiología
8.
Pharm Stat ; 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38708672

RESUMEN

What can be considered an appropriate statistical method for the primary analysis of a randomized clinical trial (RCT) with a time-to-event endpoint when we anticipate non-proportional hazards owing to a delayed effect? This question has been the subject of much recent debate. The standard approach is a log-rank test and/or a Cox proportional hazards model. Alternative methods have been explored in the statistical literature, such as weighted log-rank tests and tests based on the Restricted Mean Survival Time (RMST). While weighted log-rank tests can achieve high power compared to the standard log-rank test, some choices of weights may lead to type-I error inflation under particular conditions. In addition, they are not linked to a mathematically unambiguous summary measure. Test statistics based on the RMST, on the other hand, allow one to investigate the average difference between two survival curves up to a pre-specified time point τ $$ \tau $$ -a mathematically unambiguous summary measure. However, by emphasizing differences prior to τ $$ \tau $$ , such test statistics may not fully capture the benefit of a new treatment in terms of long-term survival. In this article, we introduce a graphical approach for direct comparison of weighted log-rank tests and tests based on the RMST. This new perspective allows a more informed choice of the analysis method, going beyond power and type I error comparison.

9.
Sensors (Basel) ; 24(11)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38894439

RESUMEN

Sixth-generation (6G) wireless networks demand a more efficient implementation of non-orthogonal multiple access (NOMA) schemes for severe multipath fading environments to serve multiple users. Using non-orthogonal multiple access (NOMA) schemes in IoT 6G networks is a promising solution to allow multiple users to share the same spectral and temporal resource, increasing spectral efficiency and improving the network's capacity. In this work, we have evaluated the performance of a novel progressive pattern interleaver (PPI) employed to distinguish the users in interleaved division multiple access (IDMA) schemes, suggested by 3GPP guidelines as a NOMA scheme, with two multi-carrier modulation schemes known as single-carrier frequency-division multiple access (SC-FDMA) and orthogonal frequency-division multiplexing (OFDM), resulting in SC-FDMA-IDMA and OFDM-IDMA schemes. Both schemes are multi-carrier schemes with orthogonal sub-carriers to deal against inter-symbol interference (ISI) and orthogonal interleavers for the simultaneous access of multiple users. It has been suggested through simulation outcomes that PPI performance is adequate with SC-FDMA-IDMA and OFDM-IDMA schemes in terms of bit error rate (BER) under multipath channel conditions. Moreover, regarding bandwidth requirement and the implementation complexity of the transmitted interleaver structure, PPI is superior to the conventional random interleaver (RI).

10.
Sensors (Basel) ; 24(14)2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-39065931

RESUMEN

The aim of the present study was to evaluate skin temperature (Tsk) asymmetries, using infrared thermography, in professional padel players before (PRE), after (POST) and 10 min after training (POST10), and their relationship with perceptual variables and training characteristics. Thermal images were taken of 10 players before, after and 10 min after a standardized technical training. After training, Tsk of the dominant side was higher than before training in the anterior forearm (30.8 ± 0.4 °C vs. 29.1 ± 1.2 °C, p < 0.01; ES = 1.9), anterior shoulder (31.6 ± 0.6 °C vs. 30.9 ± 0.6 °C, p < 0.05; ES = 1.0) posterior arm (29.5 ± 1.0 °C vs. 28.3 ± 1.2 °C, p < 0.05; ES = 1.0), and posterior forearm (30.8 ± 0.9 °C vs. 29.3 ± 1.6 °C, p < 0.05; ES = 1.1). Likewise, these differences were significant POST10 in the anterior arm, anterior forearm, anterior shoulder, posterior arm and posterior forearm. Comparing the different moments of measurement (PRE, POST and POST10), the temperature was higher POST10 in all the regions analyzed except for the shoulder, abdominals, and lower back. Also, correlations were found between fatigue variation and temperature variation between limbs (Tsk dominance), and no correlation was found except between age and posterior thigh (|r| = 0.69; p < 0.05), and between the racket mass and anterior knee (|r| = 0.81; p < 0.01). In conclusion, infrared thermography allows monitoring of skin asymmetries between limbs in professional padel players, but these asymmetries were not related to overall fatigue variation, overall pain variation, years of experience and training hours.


Asunto(s)
Temperatura Cutánea , Termografía , Humanos , Temperatura Cutánea/fisiología , Termografía/métodos , Masculino , Adulto , Rayos Infrarrojos , Adulto Joven , Antebrazo/fisiología , Atletas
11.
Int J Mol Sci ; 25(11)2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38892353

RESUMEN

Mycobacterium bovis (Mb) is the causative agent of bovine tuberculosis (bTb). Genetic selection aiming to identify less susceptible animals has been proposed as a complementary measure in ongoing programs toward controlling Mb infection. However, individual animal phenotypes for bTb based on interferon-gamma (IFNÉ£) and its use in bovine selective breeding programs have not been explored. In the current study, IFNÉ£ production was measured using a specific IFNÉ£ ELISA kit in bovine purified protein derivative (bPPD)-stimulated blood samples collected from Holstein cattle. DNA isolated from the peripheral blood samples collected from the animals included in the study was genotyped with the EuroG Medium Density bead Chip, and the genotypes were imputed to whole-genome sequences. A genome-wide association analysis (GWAS) revealed that the IFNÉ£ in response to bPPD was associated with a specific genetic profile (heritability = 0.23) and allowed the identification of 163 SNPs, 72 quantitative trait loci (QTLs), 197 candidate genes, and 8 microRNAs (miRNAs) associated with this phenotype. No negative correlations between this phenotype and other phenotypes and traits included in the Spanish breeding program were observed. Taken together, our results define a heritable and distinct immunogenetic profile associated with strong production of IFNÉ£ in response to Mb.


Asunto(s)
Estudio de Asociación del Genoma Completo , Interferón gamma , Mycobacterium bovis , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Tuberculosis Bovina , Animales , Bovinos , Mycobacterium bovis/inmunología , Interferón gamma/genética , Interferón gamma/metabolismo , Tuberculosis Bovina/genética , Tuberculosis Bovina/inmunología , Tuberculosis Bovina/microbiología , Fenotipo , Genotipo
12.
J Environ Manage ; 368: 122162, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39128352

RESUMEN

Husks of rice (RH), coffee (CH), and cholupa (CLH) were used to produce natural adsorbents. The natural adsorbents were used to remove pharmaceuticals such as diclofenac, ciprofloxacin, and acetaminophen in a mixture of distilled water. However, CH stood out for its efficiency in removing ciprofloxacin (74%) due to the higher concentration of acidic groups, as indicated by the Boehm method. In addition, CH removed 86% of ciprofloxacin individually. Therefore, CH was selected and used to remove other fluoroquinolones, such as levofloxacin and Norfloxacin. Although electrostatic interactions favored removals, better removal was observed for ciprofloxacin due to its smaller molecular volume. Then, ciprofloxacin was selected, and the effect of pH, matrix, and adsorbent doses were evaluated. In this way, using a pH of 6.2 in urine with a dose of 1.5 g L-1, it is possible to adsorb CIP concentrations in the range (0.0050-0.42 mmol L-1). Subsequently, the high R2 values and low percentages of APE and Δq indicated better fits for pseudo-second-order kinetics, suggesting a two-stage adsorption. At the same time, the Langmuir isotherm recommends a monolayer adsorption with a Qm of 25.2 mg g-1. In addition, a cost of 0.373 USD/g CIP was estimated for the process, where the material can be reused up to 4 times with a CIP removal in the urine of 51%. Consequently, thermodynamics analysis showed an exothermic and spontaneous process with high disorder. Furthermore, changes in FTIR analysis after adsorption suggest that CH in removing CIP in urine involves electrostatic attractions, hydrogen bonds and π-π interactions. In addition, the life cycle analysis presents, for the 11 categories evaluated, a lower environmental impact of the CIP removal in urine with CH than for the preparation of adsorbent, confirming that the adsorption process is more environmentally friendly than materials synthesis or other alternatives of treatments. Furthermore, future directions of the study based on real applications were proposed.

13.
J Relig Health ; 63(2): 1285-1306, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38289427

RESUMEN

Environmental changes are affecting human health. A renewal of the way we understand and relate to the planet is needed. Ecospirituality brings together the terms spirituality and environment and is born as a means of solution to this dilemma. This systematic review aimed to find out the influence of ecospirituality on global health. A search of scientific literature was carried out in the main health science databases. A review was conducted to critically evaluate the studies that identified relevant ecospiritual aspects regarding health care for communities. After a systematic search and screening, and following specified methodological criteria, a total of 14 articles were selected in the review. The findings of the review suggest that a new perspective in our worldview such as ecospirituality will provide us with the necessary keys to improve health. To understand ecospirituality, we must keep in mind the indigenous way of life, which is the clear example to follow to achieve environmental health and global health. Ecospirituality leads to a healthier environment, and as this is directly related to health, there is also an improvement in global health.


Asunto(s)
Salud Global , Humanos , Salud Ambiental
14.
Adicciones ; 0(0): 1903, 2024 Jun 27.
Artículo en Inglés, Español | MEDLINE | ID: mdl-39033526

RESUMEN

Alcohol consumption among Spanish undergraduates during their university time has increased exponentially in recent years. In addition, this lifestyle change is associated with abandoning the Mediterranean diet, increasing the risk of suffering some kind of injury and affecting their quality of life. The study was carried out with a sample of 1,057 Spanish university students, 12.1% (n = 127) of them women and 87.9% (n= 930) men. The SF-36 questionnaire was used to measure health-related quality of life, the MEDAS test to check adherence to the Mediterranean diet, and the AUDIT test to measure alcohol consumption. The results show an inverse relationship between injury and quality of life (ß= -0.020) and adherence to the Mediterranean diet (ß= -0.042) among students who have suffered some kind of injury. On the other hand, there was a positive relationship with alcohol consumption (ß= -0.046). The main conclusion is that lower alcohol consumption and higher adherence to the Mediterranean diet was associated with a better quality of life and a reduced risk of injury in undergraduates in southern Spain.


El consumo de alcohol de la juventud durante el periodo universitario ha aumentado exponencialmente en los últimos años. Además, el cambio de estilo de vida se asocia al abandono de la dieta mediterránea, aumentando el riesgo de sufrir algún tipo de lesión y afectando a su calidad de vida. El estudio se realizó con una muestra de 1057 estudiantes universitarios españoles, el 12,1% (n = 127) de mujeres y el 87,9% (n = 930) de hombres. Se utilizó el cuestionario SF-36 para medir la calidad de vida relacionada con la salud; el test MEDAS para comprobar la adherencia a la dieta mediterránea; y el test AUDIT para medir el consumo de alcohol. Los resultados muestran una relación inversa entre la lesión y la calidad de vida (ß= -0,020) y la adherencia a la dieta mediterránea (ß= -0,042) entre los estudiantes que han sufrido algún tipo de lesión. Por otro lado, se observa una relación positiva con el consumo de alcohol (ß= -0,046). La principal conclusión es que un menor consumo de alcohol y una mayor adherencia a la dieta mediterránea se asociaron con una mejor calidad de vida y un menor riesgo de lesiones en los estudiantes universitarios del sur de España.

15.
ACS Org Inorg Au ; 4(3): 338-349, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38855337

RESUMEN

Near-infrared (NIR)-emitting phosphate glasses containing Nd3+ ions are attractive for applications in laser materials and solar spectral converters. The composition-structure-property relation in this type of glass system is thus of interest from fundamental and applied perspectives. In this work, Nd3+-containing glasses were made by melting with 50P2O5-(50 - x)BaO-xNd2O3 (x = 0, 0.5, 1.0, 2.0, 3.0, 4.0 mol %) nominal compositions and studied comprehensively by density and related physical properties, X-ray diffraction (XRD), Raman spectroscopy, O 1s X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC), dilatometry, ultraviolet-visible (UV-vis)-NIR optical absorption, and photoluminescence (PL) spectroscopy with decay dynamics assessment. The densities and molar volumes of the Nd3+-containing glasses generally increased with Nd2O3 concentration also resulting in shorter Nd3+-Nd3+ distances. XRD supported the amorphous nature of the glasses, whereas the Raman spectra evolution was indicative of glass depolymerization being induced by Nd3+ ions. Oxygen (1s) and phosphorus (2p) analysis by XPS for the glass with 4.0 mol % Nd2O3 agreed with the increase in nonbridging oxygens relative to the undoped host. DSC results showed that the glass transition temperatures increased with Nd3+ concentration, with the glasses also displaying a decreased tendency toward crystallization. Dilatometry showed trends of increasing softening temperatures and decreasing thermal expansion coefficients with increasing Nd2O3 content. A glass strengthening/tightening effect was then indicated to be induced by Nd3+ with higher field strength compared to Ba2+ ions. The UV-vis-NIR absorption by Nd3+ ions increased consistently with Nd3+ concentration. The UV-vis absorption edges of the Nd-containing glasses were also analyzed via Tauc and Urbach plots for comparison with the undoped host. Concerning the PL behavior, the Nd3+ NIR emission intensity was highest for 1.0 mol % Nd2O3 and decreased thereafter. The decay kinetics of the 4F3/2 emitting state in Nd3+ ions analyzed revealed decreasing lifetimes where the decay rate analysis pointed to the prevalence of ion-ion excitation migration leading to PL quenching at high Nd3+ concentrations.

16.
ACS Phys Chem Au ; 4(4): 363-374, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39069979

RESUMEN

This work reports on various properties and analysis of optical interactions in phosphate glasses containing red-emitting Mn2+ and near-infrared (NIR)-emitting Nd3+ ions, which are of interest for energy applications and solar spectral converters. The glasses were made by melting with 50P2O5-(48 - x)BaO-2MnO-xNd2O3 (x = 0, 0.5, 1.0, and 2.0 mol %) nominal compositions and characterized by X-ray diffraction, density and related physical properties, differential scanning calorimetry, dilatometry, UV-vis-NIR optical absorption, and photoluminescence spectroscopy with decay kinetics analysis. The glasses were X-ray amorphous, wherein the physical and thermal properties of the Mn2+/Nd3+-codoped glasses were largely impacted by Nd2O3 contents. The optical absorption spectra supported the occurrence of Mn2+ ions and the lack of Mn3+ in the codoped glasses, while the absorption due to Nd3+ ions increased steadily with Nd2O3 contents. Analyzing the glass absorption edges via Tauc and Urbach plots was further pursued for a comparison. The photoluminescence evaluation showed a consistent suppression of the emission from Mn2+ ions with increasing Nd3+ concentration, while the decay kinetics revealed shorter lifetimes in connection with increased Mn2+ → Nd3+ transfer efficiencies. Excitation of Mn2+ at 410 nm, however, led to the Nd3+ NIR emission being most intense for 1.0 mol % Nd2O3, despite the 4F3/2 emission decay analysis showing lifetime shortening throughout. Considering the compromise between red and NIR emissions, the Mn-containing glass doped with 0.5 mol % Nd2O3 is put in perspective with the concept of solar spectral conversion.

17.
J Phys Chem B ; 128(12): 2995-3003, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38497578

RESUMEN

Phosphate glasses containing Nd3+, Gd3+, and Yb3+ as lanthanide ions are attractive for applications in laser materials, phototherapy lamps, and solar spectral converters. The composition-structure-property relation in this type of glass system is thus of interest from fundamental and applied perspectives. In this work, the impact of the differing ionic radius of Nd3+, Gd3+, and Yb3+ and consequent field strength on the physical properties of phosphate glasses is investigated, focusing ultimately on thermal expansion effects. The glasses were made by melting with a fixed concentration of the lanthanide ions having 50P2O5-46BaO-4Ln2O3 nominal compositions (mol %) with Ln = Nd, Gd, and Yb. The investigation encompassed measurements by X-ray diffraction (XRD), optical spectroscopy, density, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and dilatometry. XRD supported the amorphous nature of the glasses, whereas absorption and photoluminescence spectra showed the optical features of the Nd3+, Gd3+, and Yb3+ ions in the glasses. Oxygen speciation by XPS indicated an increase in nonbridging oxygens for the larger radii Nd3+ and Gd3+ ions relative to the host, contrasting with Yb3+. Phosphorus XPS analysis further supported the hypothesis that the P 2p binding energies of the glasses increased with the cation field strength of the lanthanides. The Raman spectra were interpreted based on glass depolymerization effects and the impact of Ln3+ ions with high field strength. Particularly, the band position of the symmetric out-of-chain nonbridging oxygen stretch, νs(PO2-), shifted to higher frequencies correlating with the Ln3+ field strength. Dilatometry ultimately revealed a steady decrease in the coefficient of thermal expansion for the glasses, which correlated linearly with Ln3+ field strengths and thus indicated to sustain increased glass rigidities. The various analyses performed thus illuminated the structural foundation of the thermomechanical behavior of the glasses connected with changes in the Ln3+ field strengths.

18.
Sci Rep ; 14(1): 11478, 2024 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769409

RESUMEN

The Eurasian otter Lutra lutra is a territorial semi-aquatic carnivore usually found at low densities in rivers, coastal areas, and wetlands. Its diet is based on prey associated with aquatic environments. Mediterranean rivers are highly seasonal, and suffer reduced flow during the summer, resulting in isolated river sections (pools) that sometimes can be left with a minimal amount of water, leading to concentrations of food for otters. To our knowledge, this process, which was known to field naturalists, has not been accurately described, nor have otter densities been estimated under these conditions. In this study, we describe the population size and movements of an aggregation of otters in an isolated pool in the Guadiana River in the Tablas de Daimiel National Park (central Spain), which progressively dried out during the spring-summer of 2022, in a context of low connectivity due to the absence of circulating water in the Guadiana and Gigüela rivers. Using non-invasive genetic sampling of 120 spraints collected along 79.4 km of sampling transects and spatial capture-recapture methods, we estimated the otter density at 1.71 individuals/km of river channel length (4.21 individuals/km2) in a progressively drying river pool, up to five times higher than previously described in the Iberian Peninsula. The movement patterns obtained with the spatial capture-recapture model are not quite different from those described in low density, which seems to indicate a wide home range overlap, with low signs of territoriality.


Asunto(s)
Nutrias , Ríos , Territorialidad , Animales , Nutrias/fisiología , España , Densidad de Población , Estaciones del Año , Ecosistema , Conducta Animal
19.
Materials (Basel) ; 17(11)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38893933

RESUMEN

The CO2 adsorption of a phenylene-bridged ordered mesoporous organosilica (PMO-benzene) was analyzed. The maximum capture capacity was 638.2 mg·g-1 (0 °C and 34 atm). Approximately 0.43 g would be enough to reduce the amount of atmospheric CO2 in 1 m3 to pre-industrial levels. The CO2 adsorption data were analyzed using several isotherm models, including Langmuir, Freundlich, Sips, Toth, Dubinin-Radushkevich, and Temkin models. This study confirmed the capability of this material for use in reversible CO2 capture with a minimal loss of capacity (around 1%) after 10 capture cycles. Various techniques were employed to characterize this material. The findings from this study can help mitigate the greenhouse effect caused by CO2.

20.
Vet Sci ; 11(6)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38921994

RESUMEN

The Retinta breed, an autochthonous type of Spanish beef cattle, is highly adapted to breeding in its natural environment, which is characterized by a Mediterranean climate. The origins of this breed can be traced to two ancestral bovine stocks, which gave rise to distinct morphotypes differentiated primarily by coat color, alongside other significant traits such as growth, morphological conformation and temperament. Specifically, one morphotype comprises blond animals (Rubia Andaluza), genetically resembling the ancestral Bos taurus Aquitanicus, while the other encompasses brown- and red-colored animals (Retinta Extremeña) originating from Bos taurus Turdenatus stock. Over decades, these populations have undergone hybridization, leading to a unified population, albeit with the original subpopulations largely maintaining their genetic integrity. The objective of this study was to undertake genealogical and genomic characterization of these genetic lines, including a particular subpopulation within the blond animals (Tamarona cow). To achieve this, the genealogical records of 22,004 active animals were analyzed, and over 63,000 SNPs from a total of 1030 animals were examined for genomic characterization. Genealogical analysis revealed pedigree completeness and a high level of effective population size (Ne) across the entire population, yet relatively low Ne values within each pure line (ranging from 28.38 to 34.47). These findings underscore the ongoing efforts of the National Association of Retinta Breeders (ACRE) over the past decades to mitigate the loss of variability in this breed. The genomic characterization highlights the persistent differences within the original population and the predominant influence of the Retinto line within the current breed, as evidenced by principal component analysis (PCA) and admixture analysis. Furthermore, the identification of the Tamarona subpopulation within the blond lineage underlines its unique genetic composition, warranting its recognition as an official genetic line within the current Retinta breed. Given the small population size of these lines, particularly the Tamarona subpopulation, protective measures are imperative to preserve this distinct gene pool. Such measures would enhance the genetic diversity of the Retinta breed, which is essential for sustainable breeding practices in its natural habitats.

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