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1.
Trends Biotechnol ; 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38519307

RESUMEN

Anaerobic ammonium oxidation (anammox) is an energy-efficient method for nitrogen removal that opens the possibility for energy-neutral wastewater treatment. Research on anammox over the past decade has primarily focused on its implementation in domestic wastewater treatment. However, emerging studies are now expanding its use to novel biotechnological applications and wastewater treatment processes. This review highlights recent advances in the anammox field that aim to overcome conventional bottlenecks, and explores novel and niche-specific applications of the anammox process. Despite the promising results and potential of these advances, challenges persist for their real-world implementation. This underscores the need for a transition from laboratory achievements to practical, scalable solutions for wastewater treatment which mark the next crucial phase in the evolution of anammox research.

2.
Otol Neurotol ; 45(2): 176-183, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38206066

RESUMEN

OBJECTIVE: Evaluate whether a portable, tablet-based central auditory processing (CAP) test system using native language training videos and administered by minimally trained community health workers can produce CAP results comparable to previously published norms. Our secondary aim was to determine subject parameters that influence test results. STUDY DESIGN: Cross-sectional study. SETTING: Community-based settings in Chontales, Nicaragua, New Hampshire, and Florida. PATIENTS: English- and/or Spanish-speaking children and adolescents (n = 245; average age, 12.20 yr; range, 6-18 yr). MAIN OUTCOME MEASURES: Completion of the following tests with responses comparable to published norms: Pure-tone average (PTA), gap detection threshold (GDT), fixed-level frequency threshold, masking level difference (MLD), Hearing in Noise Test (HINT), Dichotic Digits Test (DDT), and Frequency Pattern Recognition (FPR) test. RESULTS: GDT, HINT, and DDT had comparable results to previously published normative values. MLD and FPR results differed compared with previously published normative values. Most CAP tests (MLD, GDT, HINT) results were independent of age and PTA (p = 0.1-0.9). However, DDT was associated with age and PTA (p < 0.0001). CONCLUSIONS: Pediatric CAP testing can be successfully completed in remote low- and middle- income country environments using a tablet-based platform without the presence of an audiologist. Performance on DDT improved with age but deteriorated with hearing loss. Further investigation is warranted to assess the variability of FPR.


Asunto(s)
Sordera , Países en Desarrollo , Adolescente , Humanos , Niño , Estudios Transversales , Percepción Auditiva , Pruebas Auditivas
3.
J Mater Chem B ; 12(10): 2494-2504, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38170794

RESUMEN

At the time when pathogens are developing robust resistance to antibiotics, the demand for implant surfaces with microbe-killing capabilities has significantly risen. To achieve this goal, profound understanding of the underlying mechanisms is crucial. Our study demonstrates that graphene oxide (GO) nano films deposited on stainless steel (SS316L) exhibit superior antibacterial features. The physicochemical properties of GO itself play a pivotal role in influencing biological events and their diversity may account for the contradictory results reported elsewhere. However, essential properties of GO coatings, such as oxygen content and the resulting electrical conductivity, have been overlooked so far. We hypothesize that the surface potential and electrical resistance of the oxygen content in the GO-nano films may induce bacteria-killing events on conductive metallic substrates. In our study, the GO applied contains 52 wt% of oxygen, and thus exhibits insulating properties. When deposited as a nano film on an electrically conducting steel substrate, GO flakes generate a Schottky barrier at the interface. This barrier, consequently, impedes the transfer of electrons to the underlying conductive substrate. As a result, this creates reactive oxygen species (ROS), leading to bacterial death. We confirmed the presence of GO coatings and their hydrolytic stability by using X-ray photoelectron spectroscopy (XPS), µRaman spectroscopy, scanning electron microscopy (SEM), and Kelvin probe force microscopy (KPFM) measurements. The biological evaluation was performed on the MG63 osteoblast-like cell line and two selected bacteria species: S. aureus and P. aeruginosa, demonstrating both the cytocompatibility and antibacterial behavior of GO-coated SS316L substrates. We propose a two-step bactericidal mechanism: electron transfer from the bacteria membrane to the substrate, followed by ROS generation. This mechanism finds support in changes observed in contact angle, surface potential, and work function, identified as decisive factors. By addressing overlooked factors and effectively bridging the gap between understanding and practicality, we present a transformative approach for implant surfaces, combating microbial resistance, and offering new application possibilitie.


Asunto(s)
Antibacterianos , Grafito , Staphylococcus aureus , Especies Reactivas de Oxígeno/metabolismo , Antibacterianos/farmacología , Antibacterianos/química , Metales/farmacología , Oxígeno/farmacología
4.
Eur J Orthop Surg Traumatol ; 34(1): 415-423, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37566140

RESUMEN

PURPOSE: Verify if the use of locking plates in displaced three- and four-part proximal humerus fractures has meant an improvement even in patients over 70 years of age. MATERIAL AND METHODS: We performed surgery with locking plate fixation in 56 consecutive patients with three- and four-part proximal humerus fractures according to Neer's classification between 1/1/15 and 12/31/20 at our Hospital. Patient satisfaction, quality of life, functionality and radiological variables, as well as the comparison between patients older and younger than 70 years were the main outcomes. Likewise, factors and complications that may have influenced these variables were analyzed as secondary outcomes. The analysis of all these variables was performed after a minimum follow-up time of 24 months after surgery. RESULTS: 51 patients (92%) ended up satisfied or very satisfied according to the SF-36 test and with no disability or mild disability according to the DASH Score questionnaire. 46 patients (82%) obtained a satisfactory or excellent result according to the Neer scale modified by Cofield and 38 (68%) a good or excellent function according to the Constant Murley questionnaire. In 47 cases (84%) good radiological alignment was observed. Complications occurred in 20 patients (36%). The complications and the results of the SF-36, DASH Score, Neer scale modified by Cofield and Constant Murley tests depended on the radiological alignment (p = 0.009, p = 0.006, p = 0.025, p = 0.0008 and p = 0.0004). There were 37 patients younger than 70 years and 19 older than 70 years with no statistically significant differences when comparing the two groups. CONCLUSIONS: This study demonstrates that satisfactory results can be obtained with osteosynthesis with locking plates in displaced proximal humerus fractures even in patients older than 70 years of age. LEVEL OF EVIDENCE III: Retrospective Cohort, Treatment Study.


Asunto(s)
Fracturas del Húmero , Fracturas del Hombro , Humanos , Anciano , Anciano de 80 o más Años , Estudios Retrospectivos , Calidad de Vida , Fijación Interna de Fracturas/efectos adversos , Fijación Interna de Fracturas/métodos , Fracturas del Hombro/diagnóstico por imagen , Fracturas del Hombro/cirugía , Húmero , Placas Óseas , Resultado del Tratamiento
5.
Rev. cuba. med ; 62(4)dic. 2023.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1550887

RESUMEN

Introducción: La tomografía de emisión de positrones es una técnica diagnóstica no invasiva que permite tomar imágenes del organismo que muestra el metabolismo de los órganos del cuerpo. Objetivo: Destacar el valor de la PET/CT en el diagnóstico imagenológico prequirúrgico del enfermo. Presentación de caso: Se presentó un paciente masculino de 39 años sin antecedentes de importancia, con un cuadro de hipoglucemias severas de 5 años de evolución, a pesar de los múltiples estudios imagenológicos se incluyó la ecoendoscopía digestiva, lo que no fue posible evidenciar la lesión tumoral. Se le realiza PET/CT cuyo resultado fue crucial para localizar el tumor, se le dio al paciente la oportunidad de un tratamiento quirúrgico y la demostración anatomopatológica de insulinoma. Conclusiones: Los insulinomas son tumores pancreáticos poco frecuentes que provocan hiperinsulinismo endógeno y son difíciles de visualizar debido a su tamaño por las técnicas de imágenes convencionales, por lo que el PET/CT es un estudio bastante efectivo para localizar la lesión tumoral, y así realizar un procedimiento quirúrgico.


Introduction: Positron emission tomography is a non-invasive diagnostic technique, allowing images of the body to be taken that show the metabolism of the body's organs. Objective: To highlight the value of PET/CT in the pre-surgical imaging diagnosis of the patient. Case presentation: We report the case of a 39-year-old male patient with no significant medical history, but a 5-year history of severe hypoglycemia. Despite multiple imaging studies, digestive ultrasound endoscopy was included, which was not possible to demonstrate the tumor lesion. PET/CT was performed, the result of which was crucial in locating the tumor. The patient was given the opportunity for surgical treatment and the pathological demonstration of insulinoma. Conclusions: Insulinomas are rare pancreatic tumors that cause endogenous hyperinsulinism and are difficult to visualize due to their size using conventional imaging techniques, therefore PET/CT is a fairly effective study to locate the tumor lesion, and thus perform a surgical procedure.

6.
Sensors (Basel) ; 23(19)2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37836897

RESUMEN

In this article, we study the effect of annealing temperature and applied stress on the magnetic properties of Fe71.80B13.27Si11.02Nb2.99Ni0.92 and Co65.34Si12.00B10.20Cr8.48Fe3.90Mo0.08 microwires. An anomalous behavior of the coercive field is observed while applying stress, indicating nontrivial changes in the microwire magnetic anisotropy. The effect of applied stimuli on the magnetic anisotropy and magnetostriction constant in both microwires is also discussed.

7.
Sensors (Basel) ; 23(17)2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37687937

RESUMEN

As-prepared Fe-rich microwires with perfectly rectangular hysteresis loops present magnetization reversal through fast domain wall propagation, while the giant magnetoimpedance (GMI) effect in Fe-rich microwires is rather low. However, the lower cost of Fe-rich microwires makes them attractive for magnetic sensors applications. We studied the effect of conventional (furnace) annealing and Joule heating on magnetic-propertied domain wall (DW) dynamics and the GMI effect in two Fe microwires with different geometries. We observed that magnetic softness, GMI effect and domain wall (DW) dynamics can be substantially improved by appropriate annealing. Observed experimental results are discussed considering the counterbalance between the internal stresses relaxation and induced magnetic anisotropy associated with the presence of an Oersted magnetic field during Joule heating.

8.
Rev. cuba. med ; 62(2)jun. 2023.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1530128

RESUMEN

La enfermedad poliquística renal autosómica dominante es considerada la enfermedad renal genética más frecuente y es la cuarta causa de enfermedad renal crónica a nivel mundial. Afecta a cerca de 1 por cada 1000 nacidos vivos. La enfermedad poliquística hepática es la manifestación extrarrenal más frecuente de la enfermedad poliquística renal. La cirrosis hepática constituye un hallazgo tardío en esta enfermedad y su presentación es más común en el anciano, y la descompensación de la enfermedad con insuficiencia hepática como causa de muerte. Presentamos el caso de un paciente masculino de 60 años con antecedentes patológicos personales de la enfermedad poliquística renal con ascitis a tensión, y edemas en ambos miembros inferiores con datos de insuficiencia hepática y evolución desfavorable hasta su fallecimiento. Aunque la presencia de la falla hepática se asocia a un pronóstico precario, la detección precoz puede suponer el inicio de un tratamiento oportuno y apropiado que puede ser beneficioso.


Autosomal dominant polycystic kidney disease is considered the most common genetic kidney disease and the fourth leading cause of chronic kidney disease worldwide. It affects about 1 in 1,000 live births. Polycystic liver disease is the most common extrarenal manifestation of polycystic kidney disease. Liver cirrhosis is a late finding in this disease and its presentation is more common in the elderly. Decompensation of the disease, with liver failure as the cause of death, is rare in polycystic liver disease. We report the case of a 60-year-old male patient with a personal pathological history of polycystic kidney disease with tense ascites and edema in both lower limbs, with evidence of liver failure and unfavorable evolution until his death. Although the presence of liver failure is associated with poor prognosis, its early detection may mean the initiation of timely and appropriate treatment that may be beneficial.

9.
Int J Mol Sci ; 24(9)2023 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-37176107

RESUMEN

Implant-related infections are a worldwide issue that is considered very challenging. Conventional therapies commonly end up failing; thus, new solutions are being investigated to overcome this problem. The in situ delivery of the drug at the implant site appears to be more sufficient compared to systemic antibiotic therapy. In this study, we manufactured porous zirconia scaffolds using the foam replication method. To improve their overall bioactivity, they were coated with a calcium phosphate (CaP) layer containing antibiotic-loaded degradable polymer nanoparticles (NPs) obtained by the double emulsion method to achieve the antibacterial effect additionally. Encapsulation efficiency (EE) and drug loading (DL) were superior and were equal to 99.9 ± 0.1% and 9.1 ± 0.1%, respectively. Scaffolds were analyzed with scanning electron microscopy, and their porosity was evaluated. The porosity of investigated samples was over 90% and resembled the microstructure of spongy bone. Furthermore, we investigated the cytocompatibility with osteoblast-like MG-63 cells and antimicrobial properties with Staphylococcus aureus. Scaffolds coated with a CaP layer were found non-toxic for MG-63 cells. Moreover, the presence of antibiotic-loaded nanoparticles had no significant influence on cell viability, and the obtained scaffolds inhibited bacteria growth. Provided processes of fabrication of highly porous zirconia scaffolds and surface functionalization allow minimizing the risk of implant-related infection.


Asunto(s)
Nanopartículas , Andamios del Tejido , Andamios del Tejido/química , Ingeniería de Tejidos/métodos , Porosidad , Gentamicinas/farmacología , Antibacterianos/farmacología , Nanopartículas/química , Fosfatos de Calcio/química
10.
ACS Appl Mater Interfaces ; 15(17): 21699-21718, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37083334

RESUMEN

Aseptic loosening and periprosthetic infections are complications that can occur at the interface between inert ceramic implants and natural body tissues. Therefore, the need for novel materials with antibacterial properties to prevent implant-related infection is evident. This study proposes multifunctionalizing the inert ceramic implant surface by biomimetic calcium phosphate (CaP) coating decorated with antibiotic-loaded nanoparticles for bioactivity enhancement and antibacterial effect. This study aimed to coat zirconium dioxide (ZrO2) substrates with a bioactive CaP-layer containing drug-loaded degradable polymer nanoparticles (NPs). The NPs were loaded with two antibiotics, gentamicin or bacitracin. The immobilization of NPs happened by two deposition methods: coprecipitation and drop-casting. X-ray diffraction (XRD), scanning electron microscopy (SEM), and cross-section analyses were used to characterize the coatings. MG-63 osteoblast-like cells and human mesenchymal stem cells (hMSC) were chosen for in vitro tests. Antibacterial activity was assessed with S. aureus and E. coli. The coprecipitation method allowed for a favorable homogeneous distribution of the NPs within the CaP coating. The CaP coating was constituted of hydroxyapatite and octacalcium phosphate; its thickness was 3.8 ± 1 µm with cavities of around 1 µm suitable for hosting NPs with a size of 200 nm. Antibiotics were released from the coatings in a controlled manner for 1 month. The cell culture study has confirmed the excellent behavior of the coprecipitated coating, showing cytocompatibility and a homogeneous distribution of the cells on the coated surfaces. The increase in alkaline phosphatase activity showed osteogenic differentiation. The materials were found to inhibit the growth of bacteria. Newly developed coatings with antibacterial and bioactive properties are promising candidates to prevent peri-implant infectious bone diseases.


Asunto(s)
Antibacterianos , Nanopartículas , Humanos , Antibacterianos/farmacología , Antibacterianos/química , Osteogénesis , Staphylococcus aureus , Biomimética , Escherichia coli , Materiales Biocompatibles Revestidos/farmacología , Materiales Biocompatibles Revestidos/química , Fosfatos de Calcio/farmacología , Fosfatos de Calcio/química , Cerámica/farmacología , Propiedades de Superficie , Titanio/química
11.
Sensors (Basel) ; 23(7)2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-37050578

RESUMEN

Supervised learning requires the accurate labeling of instances, usually provided by an expert. Crowdsourcing platforms offer a practical and cost-effective alternative for large datasets when individual annotation is impractical. In addition, these platforms gather labels from multiple labelers. Still, traditional multiple-annotator methods must account for the varying levels of expertise and the noise introduced by unreliable outputs, resulting in decreased performance. In addition, they assume a homogeneous behavior of the labelers across the input feature space, and independence constraints are imposed on outputs. We propose a Generalized Cross-Entropy-based framework using Chained Deep Learning (GCECDL) to code each annotator's non-stationary patterns regarding the input space while preserving the inter-dependencies among experts through a chained deep learning approach. Experimental results devoted to multiple-annotator classification tasks on several well-known datasets demonstrate that our GCECDL can achieve robust predictive properties, outperforming state-of-the-art algorithms by combining the power of deep learning with a noise-robust loss function to deal with noisy labels. Moreover, network self-regularization is achieved by estimating each labeler's reliability within the chained approach. Lastly, visual inspection and relevance analysis experiments are conducted to reveal the non-stationary coding of our method. In a nutshell, GCEDL weights reliable labelers as a function of each input sample and achieves suitable discrimination performance with preserved interpretability regarding each annotator's trustworthiness estimation.

12.
J Biomed Mater Res A ; 111(9): 1322-1332, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36924189

RESUMEN

Hemocompatibility is the most significant criterion for blood-contacting materials in successful in vivo applications. Prior to the clinical tests, in vitro analyses must be performed on the biomaterial surfaces in accordance with the ISO 10993-4 standards. Designing a bio-functional material requires engineering the surface structure and chemistry, which significantly influence the blood cell activity according to earlier studies. In this study, we elucidate the role of surface terminations and polymorphs of SiC single crystals in the initial stage of the contact coagulation. We present a detailed analysis of phase, roughness, surface potential, wettability, consequently, reveal their effect on cytotoxicity and hemocompatibility by employing live/dead stainings, live cell imaging, ELISA and Micro BCA protein assay. Our results showed that the surface potential and the wettability strongly depend on the crystallographic polymorph as well as the surface termination. We show, for the first time, the key role of SiC surface termination on platelet activation. This dependency is in good agreement with the results of our in vitro analysis and points out the prominence of cellular anisotropy. We anticipate that our experimental findings bridge the surface properties to the cellular activities, and therefore, pave the way for tailoring advanced hemocompatible surfaces.


Asunto(s)
Coagulación Sanguínea , Activación Plaquetaria , Materiales Biocompatibles/química , Humectabilidad , Propiedades de Superficie , Ensayo de Materiales , Adhesividad Plaquetaria
13.
Sensors (Basel) ; 23(6)2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-36991797

RESUMEN

We studied the magnetic properties of a glass-covered amorphous microwire that was stress-annealed at temperatures distributed along the microwire length. The Sixtus-Tonks, Kerr effect microscopy and magnetic impedance techniques have been applied. There was a transformation of the magnetic structure across the zones subjected to annealing at different temperatures. The annealing temperature distribution induces the graded magnetic anisotropy in the studied sample. The variety of the surface domain structures depending on the longitudinal location has been discovered. Spiral, circular, curved, elliptic and longitudinal domain structures coexist and replace each other in the process of magnetization reversal. The analysis of the obtained results was carried out based on the calculations of the magnetic structure, assuming the distribution of internal stresses.

14.
J Cardiothorac Surg ; 18(1): 93, 2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-36964599

RESUMEN

BACKGROUND: Kommerell's aneurysm is a saccular or fusiform dilatation found in 3-8% of Kommerell's diverticulum cases. A non-dissecting rupture rate of 6% has been reported. If ruptured, emergent surgical correction is usually granted. However, evidence regarding the optimal surgical approach in this acute setting is scarce. In this case report series, we aim to describe our experience managing type-1 non-dissecting ruptured Kommerell's aneurysm with hybrid emergent surgical approaches. CASES PRESENTATION: From January 2005 to December 2020, three cases of type-1 non-dissecting ruptured Kommerell's aneurysm requiring emergent surgical repair were identified. The mean age was 66.67 ± 7.76 years, and 3/3 were male. The most common symptoms were atypical chest pain, dyspnoea, and headache (2/3). The mean aneurysm's diameter was 63.67 ± 5.69 mm. Frozen Elephant Trunk was the preferred surgical approach (2/3). The Non-Frozen Elephant Trunk patient underwent a hybrid procedure consisting of a supra-aortic debranching and a zone-2 stent-graft deployment. We found a mean clamp time of 140 ± 60.75 min, cardiac arrest time of 51.33 ± 3.06 min, and a hospital stay of 13.67 ± 5.51 days. The most common complications were surgical-site infection and shock (2/3). Only one patient died (1/3). CONCLUSION: Evidence of management for non-dissecting ruptured Kommerell's aneurysms is scarce. Additional, robust, and more extensive studies are required. The selection of the appropriate surgical approach is challenging, and each patient should be individualized. Frozen Elephant Trunk was feasible for patients requiring emergent surgical repair in our centre. However, other hybrid or open procedures can be performed.


Asunto(s)
Aneurisma Roto , Implantación de Prótesis Vascular , Anomalías Cardiovasculares , Divertículo , Procedimientos Endovasculares , Humanos , Masculino , Persona de Mediana Edad , Anciano , Femenino , Aorta Torácica/cirugía , Implantación de Prótesis Vascular/métodos , Anomalías Cardiovasculares/cirugía , Aneurisma Roto/diagnóstico por imagen , Aneurisma Roto/cirugía , Aneurisma Roto/complicaciones , Procedimientos Endovasculares/métodos , Arteria Subclavia/cirugía , Divertículo/cirugía
15.
Int J Pharm X ; 5: 100166, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36880028

RESUMEN

3D printing is driving a shift in patient care away from a generalised model and towards personalised treatments. To complement fast-paced clinical environments, 3D printing technologies must provide sufficiently high throughputs for them to be feasibly implemented. Volumetric printing is an emerging 3D printing technology that affords such speeds, being capable of producing entire objects within seconds. In this study, for the first time, rotatory volumetric printing was used to simultaneously produce two torus- or cylinder-shaped paracetamol-loaded Printlets (3D printed tablets). Six resin formulations comprising paracetamol as the model drug, poly(ethylene glycol) diacrylate (PEGDA) 575 or 700 as photoreactive monomers, water and PEG 300 as non-reactive diluents, and lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP) as the photoinitiator were investigated. Two printlets were successfully printed in 12 to 32 s and exhibited sustained drug release profiles. These results support the use of rotary volumetric printing for efficient and effective manufacturing of various personalised medicines at the same time. With the speed and precision it affords, rotatory volumetric printing has the potential to become one of the most promising alternative manufacturing technologies in the pharmaceutical industry.

16.
In. Chao Pereira, Caridad. Insuficiencia cardiaca. Conducta terapéutica en escenarios clínicos. La Habana, Editorial Ciencias Médicas, 2023. , ilus, tab.
Monografía en Español | CUMED | ID: cum-79488
17.
Membranes (Basel) ; 12(10)2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36295783

RESUMEN

Two-dimensional (2D) MXene materials have recently been the focus of membrane research due to their unique properties, such as their single-atomic-layer thickness, flexibility, molecular filtration abilities and microstructural similarities with graphene, which is currently the most efficient precursor material for gas separation applications. In addition, the potential to process nanoscale channels has motivated investigations of parameters which can improve membrane permeability and selectivity. Interlayer spacing and defects, which are still challenging to control, are among the most crucial parameters for membrane performance. Herein, the effect of heat treatment on the d-spacing of MXene nanosheets and the surface functionalization of nanolayers was shown regarding its impact on the gas diffusion mechanism. The distance of the layers was reduced by a factor of over 10 from 0.345 nm to 0.024 nm, the defects were reduced, and the surface functionalization was maintained upon treatment of the Ti3C2 membrane at 500 °C under an Ar/H2 atmosphere as compared to 80 °C under vacuum. This led to a change from Knudsen diffusion to molecular sieving, as demonstrated by single-gas permeation tests at room temperature. Overall, this work shows a simple and promising way to improve H2/CO2 selectivity via temperature treatment under a controlled atmosphere.

18.
Comput Intell Neurosci ; 2022: 7352160, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35990118

RESUMEN

In recent years, studies have been conducted to quantify the relationship between microeconomic and macroeconomic development. Macroeconomics is the orientation of microeconomic development. Existing research hopes to quantify the relationship between macroeconomics and micro-firms, rather than just focusing on economic indicators. And some empirical studies try to use the relationship between them to discuss its usefulness for micro-firm decision-making. This article focuses on applying and developing aggregate earnings in connecting microenterprise earnings and macroeconomic development. To achieve this goal, this research did a comprehensive bibliometric analysis on macro-accounting on the two most influential databases, namely, Web of Science and Scopus. It used the information visualization software VOSviewer to draw knowledge maps to sort research lines. We also analyzed the research hotspots of macro-accounting in recent years according to the year scale and combined it with the neural network PSO-LSTM model to predict their future development. It turns out that the research on aggregate earnings related to economic growth has become a research hotspot in recent years. Scopus research and development potential is better than Web of Science in this field.


Asunto(s)
Bibliometría , Desarrollo Económico , Bases de Datos Factuales , Conocimiento , Programas Informáticos
19.
J Strength Cond Res ; 36(3): 827-831, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32149882

RESUMEN

ABSTRACT: Jiménez-Reyes, P, Casado, A, González, JE, and Rodríguez-Fernández, C. Influence of hurdling clearance on sprint mechanical properties in high-level athletes. J Strength Cond Res 36(3): 827-831, 2022-Short hurdling races are sprint races in which athletes must also clear 10 hurdles. Assessing the force-velocity (F-V) profile in sprinting has been found useful for implementing individualized training programs and determining the mechanical effectiveness in force application. This study therefore compared the sprint mechanical F-V profile between flat and hurdle conditions to distinguish which mechanical capacity (i.e., maximum force [F0], maximum velocity [V0], or maximum power [Pmax]) is required to optimize performance in hurdling races. Twenty-two athletes (10 men and 12 women, aged: 22.4 ± 3.6 years old) competing at the national and elite performance levels conducted 2 maximal sprints of 40 m in both flat and hurdle conditions. F0, V0, FVslope, Pmax, and decrease and maximal ratio of horizontal force (DRF and RFpeak, respectively) were assessed for each condition. A higher F0 (effect size [ES] = 1.69) and a lower V0 (ES = 2.08), DRF (ES = 3.15) and RFpeak (ES = 1.31) were found in the hurdle condition than in the flat condition. No significant differences were observed between conditions for Pmax (ES = 0.01). These results support the potential of using the F-V profile to monitor sprint mechanics to optimize specific and individualized sprint training programs for hurdlers and sprinters. Coaches of hurdlers should thus consider implementing in their training routines exercises that were found to be effective on the development of F0, such as heavy load resisted sprints.


Asunto(s)
Rendimiento Atlético , Carrera , Adolescente , Adulto , Atletas , Ejercicio Físico , Femenino , Humanos , Cinética , Masculino , Adulto Joven
20.
Materials (Basel) ; 14(22)2021 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-34832253

RESUMEN

Heusler Ni-Mn-Sn-based alloys are good candidates for magnetic refrigeration. This application is based on cycling processes. In this work, thermal cycles (100) have been performed in three ribbons produced by melt-spinning to check the thermal stability and the magnetic response. After cycling, the temperatures were slowly shifted and the thermodynamic properties were reduced, the entropy changed at about 3-5%. Likewise, the thermomagnetic response remains similar. Thus, these candidates maintain enough thermal stability and magnetic response after cycling. Likewise, Cu addition shifts the structural transformation to higher temperatures, whereas the Curie temperature is always near 310 K. Regarding magnetic shape memory applications, the best candidate is the Ni49Mn36 Sn14Cu1 alloy.

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