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1.
Cryst Growth Des ; 24(3): 938-946, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38344677

RESUMEN

Zeolite stability, in terms of lattice energy, is revisited from a crystal-chemistry point of view. A linearized equation relates the zeolite lattice energy using simple structural data readily available from experiments or modeling. The equation holds for a large range of zeolite energies, up to 3 eV per tetrahedron with respect to quartz, and has been validated internally via two simple machine learning automatic procedures for data fitting/reference partitions and externally using data from recently synthesized zeolites. The approach is certain in locating those recently synthesized zeolites in the energy range of those experimentally known zeolites used in the parametrization of the linearized equation. Hidden intrinsic structural data-energy correlations were found for data sets built from energy-relaxed structures along with energy values computed using the same energy functions employed in the structural relaxation. The asymmetry of the structural features is relevant for an accurate description of the energy.

2.
Vet Sci ; 10(4)2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37104442

RESUMEN

As guest editors, we are pleased to present this Special Issue entitled "Assisted Reproductive Technologies (ARTs) in Domestic Mammals", comprising 10 articles of relevant interest in the field of animal reproduction [...].

3.
Animals (Basel) ; 13(4)2023 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-36830405

RESUMEN

The evolution of some fetal growth indices and arterial blood flow parameters in the umbilical cord of the embryos and fetuses of primiparous pregnant goats of Murciano-Granadina breed were analyzed by ultrasonography. Weekly ultrasonographic sessions took place from 18- to 125-days post-breeding. Fetal measures were carried out by ultrasound B-mode. This mode was used to take a series of measurements in the embryo/fetus throughout pregnancy: crown-rump length (CRL, from 24-days post-mating -dpm- to 61 dpm), trunk diameter (TD, 24-34 dpm), biparietal diameter (BPD, 28-125 dpm) and eye orbit diameter (EOD, 75-125 dpm). Spectral Doppler was used to study blood flow from umbilical artery. Different blood flow parameters were obtained as follows: Arterial Pulse, Peak Systolic Velocity (PSV), End Diastolic Velocity (EDV), Mean Velocity (MV), Systolic velocity/Diastolic velocity Ratio (S/D), Pulsatility Index (PI) and Resistance Index (RI). In this study, the umbilical cord was first noticed between 32- and 35-days post-breeding. However, these umbilical arterial blood flow parameters were not conclusive (positive S/D ratios and RI < 1) until 65-80 days of pregnancy. The explanation to these results could be that vascular development related to umbilical arteries elasticity and diameter is not good enough in early pregnancy. Therefore, these vessels have already acquired their appropriate characteristics in order to allow blood flow parameters and Doppler index measures from only 2.5 months of pregnancy. This is the first time that a detailed study of fetal growth indices and umbilical artery flow rates in fetuses from Murciano-Granadina goats has been performed throughout virtually the entire duration of gestation. In conclusion, the evolution of the fetal growth indices in this breed has determined that the umbilical artery velocimetric parameters (PSV, EDV, MV) increase significantly and the AP, S/D, PI and RI indices decrease significantly throughout the analyzed pregnancy period.

4.
Nanoscale ; 15(7): 3504-3519, 2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36723023

RESUMEN

We have studied the clusters involved in the initial stages of nucleation of Zeolitic Imidazolate Frameworks, employing a wide range of computational techniques. In the pre-nucleating solution, the prevalent cluster is the ZnIm4 cluster (formed by a zinc cation, Zn2+, and four imidazolate anions, Im-), although clusters such as ZnIm3, Zn2Im7, Zn2Im7, Zn3Im9, Zn3Im10, or Zn4Im12 have energies that are not much higher, so they would also be present in solution at appreciable quantities. All these species, except ZnIm3, have a tetrahedrally coordinated Zn2+ cation. Small ZnxImy clusters are less stable than the ZnIm4 cluster. The first cluster that is found to be more stable than ZnIm4 is the Zn41Im88 cluster, which is a disordered cluster with glassy structure. Bulk-like clusters do not begin to be more stable than glassy clusters until much larger sizes, since the larger cluster we have studied (Zn144Im288) is still less stable than the glassy Zn41Im88 cluster, suggesting that Ostwald's rule (the less stable polymorph crystallizes first) could be fulfilled, not for kinetic, but for thermodynamic reasons. Our results suggest that the first clusters formed in the nucleation process would be glassy clusters, which then undergo transformation to any of the various crystal structures possible, depending on the kinetic routes provided by the synthesis conditions. Our study helps elucidate the way in which the various species present in solution interact, leading to nucleation and crystal growth.

5.
Animals (Basel) ; 13(2)2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36670848

RESUMEN

Artificial insemination (AI) with frozen semen in goats still presents serious difficulties, especially in certain goat breeds, in spite of technological progress. The aim of this work is the in vitro study of seminal extenders adapted from those used on other species to evaluate the response of goat sperm to several homeostatic conditions in order to achieve optimal post-thaw semen quality. Three different extenders based on different activity principles were used: (1) extender according to the methodology proposed for pigs, (2) skimmed-milk-based extender according to the methodology proposed for goats in France, and (3) a new egg-yolk-based extender replacing membrane-protective surfactants with sodium dodecyl sulfate (SDS) and named by our team as extender "IMIDA". The freezing guidelines were those proposed for the freezing of porcine semen. The results obtained show that the egg-yolk-based extenders have good parameters of sperm motility at thawing, studied objectively using the computer-assisted sperm analysis (CASA) system and also subjectively. In particular, in the sperm resistance test after five hours, the thawed sperm containing SDS in their composition showed an optimal average on every evaluated parameter. The new IMIDA extender provided the highest sperm quality averages, so it could be a good extender to use in cryopreservation of semen in the caprine species.

6.
Sci Total Environ ; 856(Pt 1): 158914, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36155046

RESUMEN

The invasive alien seaweed Rugulopteryx okamurae (R.o.) has spread quickly through the Mediterranean Sea causing an unprecedented ecological impact. A solution integrated into a circular economy model is needed in order to curb the negative effects of its presence. Anaerobic digestion (AD) is proposed as a feasible process able to transform biomass into renewable energy. Nevertheless, in order to improve the methane yield and surpass the drawbacks associated with AD processes, this research proposes a thermal pretreatment and a new developed method where the macroalgae is mechanically pretreated with zeolite. Chemical and microstructure characterization of the algal biomass after pretreatments involved scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). The highest methane yields of 240 (28) and 250 (20) NLCH4 kg-1 VSadded were obtained with the new mechanical pretreatment and the thermal pretreatment at 120 °C for 45 min without zeolite, achieving a 35 % improvement against the non-pretreated algae. A direct relationship between the crystallinity index of the samples and methane production was observed. The experimental data of methane production versus time were found to be in accordance with both first-order kinetic and Transference Function mathematical models.


Asunto(s)
Phaeophyceae , Algas Marinas , Zeolitas , Biomasa , Especies Introducidas , Anaerobiosis , Metano , Biocombustibles
7.
Int J Mol Sci ; 23(24)2022 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-36555801

RESUMEN

Controlled ovarian stimulation is a necessary step in some assisted reproductive procedures allowing a higher collection of female gametes. However, consequences of this stimulation for the gamete or the offspring have been shown in several mammals. Most studies used comparisons between oocytes from different donors, which may contribute to different responses. In this work, we use the bovine model in which each animal serves as its own control. DNA methylation profiles were obtained by single-cell whole-genome bisulfite sequencing of oocytes from pre-ovulatory unstimulated follicles compared to oocytes from stimulated follicles. Results show that the global percentage of methylation was similar between groups, but the percentage of methylation was lower for non-stimulated oocytes in the imprinted genes APEG3, MEG3, and MEG9 and higher in TSSC4 when compared to stimulated oocytes. Differences were also found in CGI of imprinted genes: higher methylation was found among non-stimulated oocytes in MEST (PEG1), IGF2R, GNAS (SCG6), KvDMR1 ICR UMD, and IGF2. In another region around IGF2, the methylation percentage was lower for non-stimulated oocytes when compared to stimulated oocytes. Data drawn from this study might help to understand the molecular reasons for the appearance of certain syndromes in assisted reproductive technologies-derived offspring.


Asunto(s)
Metilación de ADN , Superovulación , Animales , Bovinos , Femenino , Superovulación/fisiología , Impresión Genómica , Oocitos/metabolismo , Técnicas Reproductivas Asistidas , Mamíferos
9.
Vet Sci ; 9(6)2022 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-35737312

RESUMEN

This study aimed to determine uterine blood flow indices by transabdominal Doppler ultrasound in sows (n = 18) under different conditions: (i) sows after estrus detection (day 0, D0); (ii) sows 2 h after artificial insemination (AI), performed 24 h after detection of estrus (day 1, D1); (iii) sows in early diestrus (day 5, D5). Moreover, three different types of seminal doses were used for AI depending on the ejaculate fraction included (F1: doses containing only the rich fraction of the ejaculate; F2: F1 + the transition fraction between rich and poor fractions; F3: F2 and poor fraction). The statistical analysis revealed significant differences in some indices regarding the period of analysis (D0, D1, and D5). Diastolic velocity and mean velocity showed lower values at D5 in comparison with D0 and D1 (p < 0.01). On the other hand, the pulsatility index and the relationship systolic velocity/diastolic velocity indicated higher values at D5 in comparison with D0 and D1 (p < 0.01). No differences were observed regarding the type of seminal dose used in any of the time points analyzed (p > 0.05). Neither insemination per se nor the type of ejaculate fraction used immediately modified the uterine vascularity, but some indices are affected by the stage of the estrus cycle (estrus vs. early diestrus).

10.
Nanoscale ; 14(19): 7332-7340, 2022 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35535713

RESUMEN

Ethylene oxide is one of the most important raw materials in the chemical industry, with an annual production close to 35 million metric tons. Despite its importance, to date, no metal has been found that can compete with the original silver bulk material catalyst discovered in 1931. Recently, a few copper and copper-silver based nanostructures have demonstrated remarkable selectivity and activity, especially when coupled with an industrial chlorine promoter. The present work evaluates the mechanistic role of chlorine as an active promoter of the selective oxidation of ethylene to ethylene oxide in the presence of a silver-copper oxide hybrid nanocatalyst (AgCuO). Experimental kinetic studies combined with density functional theory (DFT) calculations provide insight into the influence that Ag/CuO-supported chlorine atoms have over the ethylene epoxidation reaction. Remarkably, the typically described indirect route via the formation of an oxametallacycle (OMC) is also accompanied by a direct route. Furthermore, the presence of chlorine seems to facilitate a more favorable adsorption energy for ethylene oxide (EO) than for acetaldehyde (AA), the main reaction by-product. As a result, complete oxidation of EO can be further prevented in the presence of this AgCuO hybrid heteronanostructure.

11.
Behav Modif ; 46(1): 230-253, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33215506

RESUMEN

A component analysis is an approach where two or more independent variables are evaluated as a package and independently. The approach is used to assess and identify which component of a treatment package is the most effective. The purpose of this review is to document the application of component analyses to improve or mitigate non-academic behaviors with individuals with disabilities. We identified 21 research articles that used a component analysis to evaluate treatment packages with students who were identified as having or at-risk for a disability in classroom and/or alternative settings. Results from reviewing 21 articles (22 cases) indicate that 11 intervention packages had a single component that was critical for successful behavior change. Two articles suggested the entire intervention package was necessary while nine articles did not report a critical component or had variable results pertaining to critical components. The benefits and drawbacks of using component analyses for single case research are discussed. Implications for future research are also presented.


Asunto(s)
Personas con Discapacidad , Estudiantes , Educación , Humanos
12.
Behav Anal Pract ; 14(3): 728-733, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34631376

RESUMEN

The present brief practice examined 6 randomly selected studies from the Journal of Applied Behavior Analysis that included functional analysis data replotted on the functional analysis celeration chart (FACC). The FACC showcases the practicality of a standard celeration chart- derived visual display. The research question asked, what level values occurred related to the original authors' determination of function? Results indicated all functions had a ×2 level multiplier or higher when placed on the FACC.

13.
In. Sousa, Islândia Carvalho; Guimarães, Maria Beatriz; Gallego Pérez, Daniel F. Experiências e reflexões sobre medicinas tradicionais, complementares e integrativas em sistemas de saúde nas Américas / Experiencias y reflexiones sobre medicinas tradicionales, complementarias e integradoras en los sistemas de salud de las Américas. Recife, Fiocruz/PE;ObservaPICS, 2021. p.102-113, graf.
Monografía en Español | LILACS, MTYCI | ID: biblio-1151979

RESUMEN

La Vigilancia en Salud es una de las fortalezas del Sistema Nacional de Salud Cubano, en el cual los profesionales sanitarios desempeñan una labor fundamental en cada nivel del mismo como ente activo de dicha vigilancia. Tal empeño demanda de una formación académica con un enfoque biopsicosocial, acompañado del desarrollo de un pensamiento salubrista desde el mismo inicio de su formación.


Asunto(s)
Vigilancia Sanitaria , Productos Biológicos , Acupuntura , Terapias Complementarias , Aparatos Sanitarios , Cuba , Sistemas Nacionales de Salud
14.
Animals (Basel) ; 11(1)2020 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-33374860

RESUMEN

The early identification of infertile males improves reproduction efficiency at a production level and is essential to secure high production rates. Before entering a breeding program, males must pass an initial breeding soundness examination (BSE) which consist of several diagnostic exams whose end point is to estimate their future fertility. There is ongoing research to find new markers that allow better identification of fertile males. Doppler mode allows the quantitative and qualitative evaluation of the irrigation of organs. When evaluating the reproductive system, Doppler mode has been successfully used for the evaluation of the uterine and ovarian irrigation. In males, it is gaining relevance for the evaluation of testicular irrigation. Researchers have found a relationship between pulsed-wave Doppler velocimetric parameters and seminal quality in various domestic animal species. This suggests Doppler ultrasound parameters should be considered as objective parameters to evaluate testicular function. In this review, we analyze the results in the main domestic animal species and discuss the differences and similarities among the results. We also discuss the effect of the location of the measurements, breed, season and laterality in the measurement of Doppler velocimetric parameters as well as the impact and limitations of this method of assessing breeding soundness.

15.
Artículo en Inglés | MEDLINE | ID: mdl-32727042

RESUMEN

The use of telemedicine has greatly increased, largely derived from the COVID-19 pandemic, which has created the need for a guide aimed towards the adequate management of a modality of health care: the video consultation. A Delphi study composed of three rounds was conducted with 16 experts in holding video consultations and managing non-technical skills from different specialties and nationalities to conceive a consensus on the criteria needed for properly managing video consultations by healthcare professionals. The consensus criteria were defined by three dimensions (preparation of video consultation, video consultation process, and post-video consultation) and their corresponding items. Excellent consensus data was obtained; therefore, use is recommended by any healthcare professional who is going to utilize a video consultation, in order to manage it effectively.


Asunto(s)
Telemedicina/normas , Adulto , Betacoronavirus , COVID-19 , Medios de Comunicación , Infecciones por Coronavirus , Atención a la Salud , Técnica Delphi , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral , Derivación y Consulta , SARS-CoV-2 , Telemedicina/métodos
16.
J Immigr Minor Health ; 22(2): 255-265, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31630315

RESUMEN

The health assets model focuses on recognizing the strengths, capacities and resources of individuals and their communities to improve health control processes. This study focuses on identifying and comparing the transcultural and cultural assets in health as accounted for by 45 young Romanians, Moroccans and Spaniards living in southern Spain. The research uses a photovoice method to understand what young people consider to boost their health. Of all the photographs taken, each young person selected the six most relevant images, and individual interviews were carried out. Both images and interviews were analysed qualitatively using Atlas Ti. We identified 40 transcultural assets in health that were common among the 3 cultural groups and 7 cultural assets that were specific to cultural groups. The seven assets include religion and spirituality, cultural symbols, medicine, traditional food, thinness, freedom/autonomy and plants. The definition of transcultural and cultural health assets facilitates the development of educational health interventions that reinforce the strengths of others in a culturally sensitive manner.


Asunto(s)
Cultura , Emigrantes e Inmigrantes , Determinantes Sociales de la Salud/etnología , Adolescente , Etnicidad , Humanos , Entrevistas como Asunto , Marruecos/etnología , Fotograbar , Investigación Cualitativa , Rumanía/etnología , España
17.
Gastroenterol Hepatol ; 42 Suppl 1: 20-25, 2019 Sep.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32560769

RESUMEN

Chronic hepatitis C virus infection is a systemic disease that impairs the quality of life of affected individuals. The impairment is not only due to physiological factors, such as the non-hepatic manifestations of the disease or certain symptoms such as fatigue, weakness and nausea, but is also due to the substantial psychological impact of the infection. Treatment with direct-acting antivirals (DAA) has been demonstrated to substantially improve patient's quality of life, starting in the initial phases. Supplement information: This article is part of a supplement entitled "The value of simplicity in hepatitis C treatment", which is sponsored by Gilead. © 2019 Elsevier España, S.L.U. All rights reserved.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Calidad de Vida , Hepatitis C Crónica/psicología , Humanos , Resultado del Tratamiento , Rendimiento Laboral
18.
Phys Chem Chem Phys ; 20(27): 18647-18656, 2018 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-29955743

RESUMEN

The development of new interatomic potentials to model metallic systems is a difficult task, due in part to the dependence between the parameters that describe the electron density and the short-range interactions. Parameter search methods are prone to false convergence. To solve this problem, we have developed a methodology for obtaining the electron density parameters independently of the short-range interactions, so that physically sound parameters can be obtained to describe the electron density, after which the short-range parameters can be fitted, thus reducing the complexity of the process and yielding better interatomic potentials. With the new method we can develop self-consistent, accurate force fields, using solely calculations, without the need to fit to experimental data. Density functional theory calculations are used to compute the observables with which the potential is fit. We applied the method to a Ni-based Inconel 625 superalloy (IN625), modelled here as Ni, Cr, Mo and Fe solid solution alloys. The capability of the force fields developed using this new method is validated, by comparing the structural and thermo-elastic properties predicted with the force fields, with the corresponding experimental data, both for single crystals and polycrystalline alloys.

19.
Phys Chem Chem Phys ; 20(26): 18047-18055, 2018 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-29932198

RESUMEN

We introduce a method to allow the screening of large configurational spaces of heteroatom distributions in zeotype materials. Based on interatomic potential calculations of configurations containing up to two heteroatoms per cell, we parameterize an atomistic effective Hamiltonian to describe the energy of multiple substitutions, with consideration of both short- and long-range interactions. Then, the effective Hamiltonian is used to explore the full configurational space at other compositions, allowing the identification of the most stable structures for further analysis. We illustrate our approach with the aluminogermanate PKU-9, where we show that increasing the aluminium concentration changes the likely siting of Al, in agreement with experiment.

20.
Angew Chem Int Ed Engl ; 57(28): 8453-8457, 2018 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-29873868

RESUMEN

We report a new family of titanium-organic frameworks that enlarges the limited number of crystalline, porous materials available for this metal. They are chemically robust and can be prepared as single crystals at multi-gram scale from multiple precursors. Their heterometallic structure enables engineering of their photoactivity by metal doping rather than by linker functionalization. Compared to other methodologies based on the post-synthetic metallation of MOFs, our approach is well-fitted for controlling the positioning of dopants at an atomic level to gain more precise control over the band-gap and electronic properties of the porous solid. Changes in the band-gap are also rationalized with computational modelling and experimentally confirmed by photocatalytic H2 production.

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