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Understanding the interplay between individual magnetic impurities and superconductivity is crucial for bottom-up construction of novel phases of matter. Sub-gap bound states that are used in this endeavor are typically considered as independent entities that each result from the exchange scattering between the respective impurity orbitals and electrons of the superconducting condensate. Here we present experimental evidence of individual multi-spin impurities where the sub-gap states are not independent. Specifically, we find that by tuning the energy of the state closest to zero through zero, all other sub-gap states change particle-hole asymmetry as well. We show that this can be understood by including Hund's coupling, which favors high-spin configurations, into a multi-orbital Anderson model. Unlike for the case of independent spins, the transition we observe signals the simultaneous departure of more than one quasiparticle from the impurity, while the parity of the ground state may remain unchanged. Our results show that Hund's coupling is not only crucial in generating high-spin impurities, but also to understand the transition between two distinct ground states, and should therefore be taken into account for e.g. impurity-based band-structure engineering.
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We investigated decays of ^{51,52,53}K at the ISOLDE Decay Station at CERN in order to understand the mechanism of the ß-delayed neutron-emission (ßn) process. The experiment quantified neutron and γ-ray emission paths for each precursor. We used this information to test the hypothesis, first formulated by Bohr in 1939, that neutrons in the ßn process originate from the structureless "compound nucleus." The data are consistent with this postulate for most of the observed decay paths. The agreement, however, is surprising because the compound-nucleus stage should not be achieved in the studied ß decay due to insufficient excitation energy and level densities in the neutron emitter. In the ^{53}K ßn decay, we found a preferential population of the first excited state in ^{52}Ca that contradicted Bohr's hypothesis. The latter was interpreted as evidence for direct neutron emission sensitive to the structure of the neutron-unbound state. We propose that the observed nonstatistical neutron emission proceeds through the coupling with nearby doorway states that have large neutron-emission probabilities. The appearance of "compound-nucleus" decay is caused by the aggregated small contributions of multiple doorway states at higher excitation energy.
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Isomer spectroscopy of heavy neutron-rich nuclei beyond the N=126 closed shell has been performed for the first time at the Radioactive Isotope Beam Factory of the RIKEN Nishina Center. New millisecond isomers have been identified at low excitation energies, 985.3(19) keV in ^{213}Tl and 874(5) keV in ^{215}Tl. The measured half-lives of 1.34(5) ms in ^{213}Tl and 3.0(3) ms in ^{215}Tl suggest spins and parities 11/2^{-} with the single proton-hole configuration πh_{11/2} as leading component. They are populated via E1 transitions by the decay of higher-lying isomeric states with proposed spin and parity 17/2^{+}, interpreted as arising from a single πs_{1/2} proton hole coupled to the 8^{+} seniority isomer in the ^{A+1}Pb cores. The lowering of the 11/2^{-} states is ascribed to an increase of the πh_{11/2} proton effective single-particle energy as the second νg_{9/2} orbital is filled by neutrons, owing to a significant reduction of the proton-neutron monopole interaction between the πh_{11/2} and νg_{9/2} orbitals. The new ms isomers provide the first experimental observation of shell evolution in the almost unexplored N>126 nuclear region below doubly magic ^{208}Pb.
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Nearly 80% of the world's population trusts traditional medicine and plant-based drug compounds to improve health, and more than 50% of women who participated in a study have used herbal remedies during pregnancy. Bocconia frutescens L. is a plant native to tropical America, where infusion of its leaves has been widely used for the treatment of several gastrointestinal disorders. We have already shown that orogastric consumption of B. frutescens L. during the organogenesis period at concentrations equivalent to human consumption produces teratogenic effects in rats, but effects on progeny development have not yet been studied. In this study, we aimed to investigate the possible association between the consumption of B. frutescens L. at a dose equivalent to that consumed by humans and the neurological development of rat progeny. Pregnant Wistar rats were administered lyophilized B. frutescens L. extract at 300 mg/kg/day or vehicle via the orogastric route during the organogenesis period (gestation days 7-13). The physical development and sensory and motor maturation of their offspring during lactation were analyzed with a battery of reflex and physical tests. B. frutescens L. produced a significant delay in physical development and sensorimotor maturation, compared to the control group. Proton nuclear magnetic resonance spectroscopy analysis showed signals for both flavonoids and alkaloids in the B. frutescens L. extract. We conclude that the delay in physical and neurological development could be interpreted as alterations in the maturation of some neuronal circuitries induced by B. frutescens L.
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Extratos Vegetais , Efeitos Tardios da Exposição Pré-Natal , Ratos Wistar , Animais , Feminino , Ratos , Gravidez , Extratos Vegetais/farmacologia , MasculinoRESUMO
Pd/ZnO nanocomposites were successfully synthesized by means of one and two pot synthesis and applied in the photodegradation of Rh6G. The nanocomposites were characterized by XRD, SEM, TEM, FTIR and micro-Raman spectroscopies. It was found the presence of PdZn2, PdO and agglomerated particles in the support surface for the Palladium-based nanocomposites fabricated by one-pot route; the two-step method allowed the formation of spherical Pd nanoparticles, with homogeneous distribution in the nanocomposite matrix, with an average size of 2.16 nm. The results show higher photocatalytic efficiency for the samples fabricated under the two-step approach compared to the one-pot synthesis. Based on experimental results, density functional theory (DFT) calculations were carried out to understand the enhancement photocatalytic of Pd/ZnO nanocomposites. To achieve it, the ZnO (001) and (101) surfaces were built and decorated by different Pd coverages. The theoretical results indicated two different photocatalytic mechanisms. In ZnO (001) case, the electrons flowed from surface to Pd, generating the superoxide radical anion (â O2-). Furthermore, the density of states of the ZnO (001) surface was modified by impurity Pd-d states at proximity to the conduction states, which may work as electron acceptors states. On the other hand, we found that the electrons flow from Pd to ZnO (101) surface, inducing the formation of â OH and â O2- for the degradation of Rh6G. The density of states of the ZnO (101) revealed a reduction in its bandgap, due to Pd-d states localized above valence states. Hence, our theoretical results suggest that the Pd-d states may facilitate the mobility of electrons and holes in (001) and (101) surfaces, respectively, reducing the rate of charge recombination.
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The high cognitive and/or emotional demands of competition can lead to a state of mental fatigue which has shown to be detrimental to soccer performance. However, there is a need to further understand the true mental demands of soccer players. The aim of the present study was to analyze the influence of motivation and the perceived requirements of the next match on mental fatigue perceived by soccer players over the passing of a season. The combined effect of both variables on the perception of mental fatigue, as well as the influence of the time of the season on perceived mental fatigue, were also analyzed. Twenty-six semi-professional Spanish male players (M = 26.31 ± 5.18 years) participated in the present study, conducted during the 2020-2021 season. Perceived mental fatigue and motivation were measured at each training session. The perceived requirements of the next match were also measured in each of the competitive weeks. Linear mixed models were run with R Studio to examine the influence of motivation and the perceived difficulty of the next match on perceived mental fatigue, the combined effect of both variables on perceived mental fatigue, and the influence of the passing of the season on perceived mental fatigue. The results showed a negative and significant influence of motivation on perceived mental fatigue (p < 0.001) and a positive and significant influence of the perceived requirements of the next match on perceived mental fatigue (p < 0.001). Regarding the combined effect, there was a positive and significant effect (p < 0.01) of the perceived difficulty of the next match on the relation between motivation and perceived mental fatigue. A negative influence of season passage on perceived mental fatigue levels was found (p < 0.001). We recommended coaches to consider using the most motivating training tasks when higher next-match requirements are perceived and to be careful with avoidance strategies for mental fatigue, especially at the beginning of the season.
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Desempenho Atlético , Futebol , Humanos , Masculino , Motivação , Futebol/psicologia , Esforço Físico , Estações do Ano , Fadiga Mental , Desempenho Atlético/psicologiaRESUMO
Recent studies in mice have indicated that the gut microbiome can regulate bone tissue strength. However, prior work involved modifications to the gut microbiome in growing animals and it is unclear if the same changes in the microbiome, applied later in life, would change matrix strength. Here we changed the composition of the gut microbiome before and/or after skeletal maturity (16 weeks of age) using oral antibiotics (ampicillin + neomycin). Male and female mice (n=143 total, n=12-17/group/sex) were allocated into five study groups:1) Unaltered, 2) Continuous (dosing 4-24 weeks of age), 3) Delayed (dosing only 16-24 weeks of age), 4) Initial (dosing 4-16 weeks of age, suspended at 16 weeks), and 5) Reconstituted (dosing from 4-16 weeks following by fecal microbiota transplant from Unaltered donors). Animals were euthanized at 24 weeks of age. In males, bone matrix strength in the femur was 25-35% less than expected from geometry in mice from the Continuous (p= 0.001), Delayed (p= 0.005), and Initial (p=0.040) groups as compared to Unaltered. Reconstitution of the gut microbiota, however, led to a bone matrix strength similar to Unaltered animals (p=0.929). In females, microbiome-induced changes in bone matrix strength followed the same trend as males but were not significantly different, demonstrating sex-related differences in the response of bone matrix to the gut microbiota. Minor differences in chemical composition of bone matrix were observed (Raman spectroscopy). Our findings indicate that microbiome-induced impairment of bone matrix in males can be initiated and/or reversed after skeletal maturity. The portion of the femoral cortical bone formed after skeletal maturity (16 weeks) is small; however, this suggests that microbiome-induced changes in bone matrix occur without osteoblast/osteoclast turnover using an, as of yet unidentified mechanism. These findings add to evidence that the mechanical properties of bone matrix can be altered in the adult skeleton.
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INTRODUCTION: Huntington disease (HD) is a hereditary neurodegenerative disorder. Thanks to predictive diagnosis, incipient clinical characteristics have been described in the prodromal phase. OBJECTIVE: To compare performance in cognitive tasks of carriers (HDC) and non-carriers (non-HDC) of the huntingtin gene and to analyse the variability in performance as a function of disease burden and proximity to the manifest stage (age of symptom onset). METHOD: A sample of 146 participants in a predictive diagnosis of HD programme were divided into the HDC (41.1%) and non-HDC groups (58.9%). Mathematical formulae were used to calculate disease burden and proximity to the manifest stage in the HDC group; these parameters were correlated with neuropsychological performance. RESULTS: Significant differences were observed between groups in performance on the Mini-Mental State Examination (MMSE), Stroop-B, Symbol-Digit Modalities Test (SDMT), and phonological fluency. In the HDC group, correlations were observed between disease burden and performance on the MMSE, Stroop-B, and SDMT. The group of patients close to the manifest stage scored lowest on the MMSE, Stroop-B, Stroop-C, SDMT, and semantic verbal fluency. According to the multivariate analysis of covariance, the MMSE effect shows statistically significant differences in disease burden and proximity to onset of symptoms. CONCLUSIONS: Members of the HDC group close to the manifest phase performed more poorly on tests assessing information processing speed and attention. Prefrontal cognitive dysfunction appears early, several years before the motor diagnosis of HD.
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Transtornos Cognitivos , Disfunção Cognitiva , Doença de Huntington , Humanos , Doença de Huntington/genética , Cognição , Efeitos Psicossociais da DoençaRESUMO
Diet formulation in a pasture-based dairy system is a challenge as the quality and quantity of available pasture, which generally constitutes the base diet, is constantly changing. The objective of this paper is to cover a more in-depth review of the nutritional characteristics of pasture-based diets, identifying potential system, plant, and animal factors that condition pasture dietary inclusion in dairy cows. In practice, there is a wide diversity of pasture-based systems with predominant to minimal use of pasture requiring a more specific classification that potentially considers the amount and time of access to pasture, access to housing, length of grazing season, seasonality of calving, and level and method of supplementation. There are important differences in the nutritional quality between pasture species and even cultivars. However, under management practices that promote maintenance of pasture in a vegetative state as well as controlling the availability of pasture, it is possible to achieve high dry matter intakes (â¼2.9%-3.4% of live weight) of pasture with moderate to high diet energy density, protein supply, and digestibility. The amount of pasture to include in the diet will depend on several factors, such as the type of production system, the cost of supplementary feeds, and the farmer's objectives, but inclusions of â¼40% to 50% of the diet seem to potentially reduce costs while apparently not limiting voluntary feed intake. Considering that there seems to be a continuum of intermediate management systems, a better understanding of the factors inherent to the feed ingredients used, as well as the use of nutrients by cows, and potential interactions between animal × system should be addressed in greater depth. This requires a meta-analysis approach, but given the diversity of the pasture-based system in practice, the existing information is highly fragmented. A clear definition of "subsystems" is necessary to direct the future research and development of mechanistic models.
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Lactação , Leite , Animais , Bovinos , Feminino , Humanos , Ração Animal/análise , Indústria de Laticínios/métodos , Dieta/veterinária , Ingestão de Alimentos , Leite/metabolismoRESUMO
OBJECTIVE: Hypertension and smoking during pregnancy have been linked to various adverse maternal and fetal outcomes. The objective of this work is to study how the smoking influences the development of hypertension, its effects on the pregnant woman, and on the newborn. MATERIALS AND METHODS: An observational study in two phases was carried out: the descriptive first phase allows characterization of the sample and the analytical second phase is a case-control nested in a retrospective cohort corresponding to pregnancy. RESULTS: A total of 712 women were included in the study. Of the 672 (94.4%) non-hypertensive women, 533 (79.3%) were non-smoking and 139 (20.7%) smoking. For the 40 (5.6%) hypertensive women, 30 (75.0%) were non-smoking and 10 (25.0%) smoking. The prevalence of hypertension was of 5.6%. Women who quit smoking before pregnancy saw a reduced risk of hypertension. For women who smoke during pregnancy, those of younger ages, with a normal body mass index, who are primiparous, employed and with a low-medium level of education have higher risk of hypertension. The risk of hypertension according to the level of physical activity during leisure time follows a "U" shape, with those who perform light physical activity at the lowest risk of hypertension. Hypertensive women have a higher risk of small for gestational age newborns. Smoking does not pose an additional risk for adverse outcomes once hypertension is diagnosed. CONCLUSIONS: Future studies should aim to determine the role of smoking habit in the appearance of hypertension in pregnancy in order to establish adequate intervention guidelines that may aid in reducing the prevalence of hypertension.
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Hipertensão , Resultado da Gravidez , Fumar , Humanos , Gravidez , Feminino , Adulto , Estudos Retrospectivos , Fumar/epidemiologia , Fumar/efeitos adversos , Recém-Nascido , Estudos de Casos e Controles , Prevalência , Espanha/epidemiologia , Hipertensão/epidemiologia , Hipertensão/etiologia , Hipertensão Induzida pela Gravidez/epidemiologia , Hipertensão Induzida pela Gravidez/etiologia , Adulto Jovem , Fatores de Risco , Exercício Físico , Abandono do Hábito de Fumar/estatística & dados numéricos , Estudos de CoortesRESUMO
Introducción: el correcto manejo de la hipotensión arterial durante la hemodiálisis es fundamental en la formación y trabajo del personal de enfermería nefrológica del Centro Médico Naval. El personal debe tener conocimientos suficientes sobre la hipotensión y sus factores asociados que le ayuden a predecirla y actuar de manera preventiva, así como con habilidades instrumentales para llevar a cabo medidas en la práctica. Objetivo: analizar la competencia clínica del personal de enfermería en el servicio de hemodiálisis del Centro Médico Naval con respecto a su formación académica y experiencia profesional en el manejo de la hipotensión arterial intradialítica. Metodología: estudio prospectivo, descriptivo y observacional. Se emplearon dos instrumentos: una adaptación del Cuestionario de conocimientos para el manejo de hemodiálisis de Miller y la Guía de observación de habilidades instrumentales en el personal de enfermería de Murillo. Resultados: se contó con una muestra de doce enfermeros pertenecientes al servicio de hemodiálisis. El 33.3% mostró un nivel regular de competencia clínica y 66.7% un nivel bueno. En promedio, la competencia clínica se ubicó en 78%. Discusión: los resultados obtenidos difieren de los reportados en otras investigaciones, tanto por el año de aplicación como de los sujetos evaluados. Limitaciones: se contó con una muestra baja debido a que el personal del servicio no es numeroso. Conclusiones: es necesario reforzar los conocimientos del personal sobre el tema. Sin embargo, se observó que las habilidades instrumentales fueron excelentes en todos los casos. No se observa relación con el nivel de estudios o la experiencia profesional.
Introduction: the correct management of arterial hypotension during hemodialysis is fundamental in the training and work of the nephrological nursing staff at the Naval Medical Center. The staff must have sufficient knowledge about hypotension and its associated factors to help them predict it and act preventively, as well as instrumental skills to carry out measures in practice. Objective: to analyze the clinical competence of the nursing staff in the hemodialysis service of the Naval Medical Center concerning their academic training and profesional experience in the management of intradialytic arterial hypotension. Methodology: a prospective, descriptive, and observational study. Two instruments were used: an adaptation of Miller's Hemodialysis Management Knowledge Questionnaire and Murillo's Guide to Observation of Instrumental Skills in Nursing Personnel. Results: There was a sample of twelve nurses belonging to the hemodialysis service. 33.3% percent showed a fair level of clinical competence and 66.7% a good level. On average, clinical competence was 78%. Discussion: the results obtained differ from those reported in other studies, in terms of both the year of application and the subjects evaluated. Limitations: there was a low sample size due to the small number of service personnel. Conclusions: it is necessary to reinforce the knowledge of the personnel on the subject. However, it was observed that instrumental skills were excellent in all cases. No relationship was observed with the level of studies or professional experience.
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Recursos Humanos de Enfermagem , Diálise Renal , Competência Clínica , HipotensãoRESUMO
The ß decays from both the ground state and a long-lived isomer of ^{133}In were studied at the ISOLDE Decay Station (IDS). With a hybrid detection system sensitive to ß, γ, and neutron spectroscopy, the comparative partial half-lives (logft) have been measured for all their dominant ß-decay channels for the first time, including a low-energy Gamow-Teller transition and several first-forbidden (FF) transitions. Uniquely for such a heavy neutron-rich nucleus, their ß decays selectively populate only a few isolated neutron unbound states in ^{133}Sn. Precise energy and branching-ratio measurements of those resonances allow us to benchmark ß-decay theories at an unprecedented level in this region of the nuclear chart. The results show good agreement with the newly developed large-scale shell model (LSSM) calculations. The experimental findings establish an archetype for the ß decay of neutron-rich nuclei southeast of ^{132}Sn and will serve as a guide for future theoretical development aiming to describe accurately the key ß decays in the rapid-neutron capture (r-) process.
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BACKGROUND: Prosthetic joint infection is one of the most serious complications in orthopedics. Prognostic systematic reviews (SRs) detecting and assessing factors related to prosthetic joint infection, allow better prediction of risk and implementation of preventive measures. Although prognostic SRs are increasingly frequent, their methodological field presents some knowledge gaps. PURPOSE: To carry out an overview of SR assessing risk factors for prosthetic joint infection, describing and synthesizing their evidence. Secondarily, to assess the risk of bias and methodological quality. MATERIAL AND METHODS: We conducted a bibliographic search in 4 databases (May 2021) to identify prognostic SR evaluating any risk factor for prosthetic joint infection. We evaluated risk of bias with the ROBIS tool, and methodological quality with a modified AMSTAR-2 tool. We computed the overlap degree study between included SR. RESULTS: Twenty-three SRs were included, studying 15 factors for prosthetic joint infection, of which, 13 had significant association. The most frequently studied risk factors were obesity, intra-articular corticosteroids, smoking and uncontrolled diabetes. Overlapping between SR was high for obesity and very high for intra-articular corticoid injection, smoking and uncontrolled diabetes. Risk of bias was considered low in 8 SRs (34.7%). The modified AMSTAR-2 tool showed important methodological gaps. CONCLUSIONS: Identification of procedural-modifiable factors, such as intra-articular corticoids use, can give patients better results. Overlapping between SR was very high, meaning that some SRs are redundant. The evidence on risk factors for prosthetic joint infection is weak due to high risk of bias and limited methodological quality.
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Within the framework of effective mass theory, we investigate the effects of spin-orbit interaction (SOI) and Zeeman splitting on the electronic properties of an electron confined in GaAs single quantum rings. Energies and envelope wavefunctions in the system are determined by solving the Schrödinger equation via the finite element method. First, we consider an inversely quadratic model potential to describe electron confining profiles in a single quantum ring. The study also analyzes the influence of applied electric and magnetic fields. Solutions for eigenstates are then used to evaluate the linear inter-state light absorption coefficient through the corresponding resonant transition energies and electric dipole matrix moment elements, assuming circular polarization for the incident radiation. Results show that both SOI effects and Zeeman splitting reduce the absorption intensity for the considered transitions compared to the case when these interactions are absent. In addition, the magnitude and position of the resonant peaks have non-monotonic behavior with external magnetic fields. Secondly, we investigate the electronic and optical properties of the electron confined in the quantum ring with a topological defect in the structure; the results show that the crossings in the energy curves as a function of the magnetic field are eliminated, and, therefore, an improvement in transition energies occurs. In addition, the dipole matrix moments present a non-oscillatory behavior compared to the case when a topological defect is not considered.
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INTRODUCTION: Metabolic (dysfunction) associated fatty liver disease (MAFLD) and gallstone disease are entities that share similar risk factors. Numerous publications confirm their elevated frequency, but few studies have considered their prevalence and possible association. AIMS: To determine the prevalence of MAFLD in patients with gallstone disease and the usefulness of liver biopsy for diagnosing the liver disease. MATERIALS AND METHODS: A prospective study was conducted on patients that underwent laparoscopic cholecystectomy, in whom liver biopsy was performed. VARIABLES ANALYZED: Anthropometric characteristics, biochemical profile, conventional ultrasound, risk factors, and histopathologic study of the liver biopsy. STATISTICAL ANALYSIS: Descriptive statistics were carried out for the quantitative variables and the Student's t test and multivariate analysis through binary logistic regression were employed for the continuous variables, utilizing IBM-SPSS, 25.0 (Windows) software. RESULTS: A total of 136 patients were classified into 2 groups: 40 (29.41%) with normal liver and 96 (70.59%) with MAFLD. Of the 136 patients, 71 patients (52.21%) corresponded to hepatic steatosis, 21 (15.44%) to steatohepatitis, and 4 (2.94%) to cirrhosis. Perisinusoidal inflammation was found in 39 cases (28.68%) and fibrosis was found in 10 (7.35%). The risk factors for both groups were age, diabetes, high blood pressure, and obesity. Glucose, triglyceride, and aminotransferase levels were significantly higher in the MAFLD group and conventional ultrasound demonstrated moderate concordance for its detection. DISCUSSION AND CONCLUSIONS: The results confirmed the elevated frequency of MAFLD associated with gallstone disease, justifying liver biopsy during cholecystectomy for diagnosing MAFLD.
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Colelitíase , Hepatopatia Gordurosa não Alcoólica , Humanos , Prevalência , México/epidemiologia , Estudos ProspectivosRESUMO
BACKGROUND: Prosthetic joint infection is one of the most serious complications in orthopedics. Prognostic systematic reviews (SR) detecting and assessing factors related to prosthetic joint infection, allow better prediction of risk and implementation of preventive measures. Although prognostic SR are increasingly frequent, their methodological field presents some knowledge gaps. PURPOSE: To carry out an overview of SR assessing risk factors for prosthetic joint infection, describing and synthesizing their evidence. Secondarily, to assess the risk of bias and methodological quality. MATERIAL AND METHODS: We conducted a bibliographic search in 4databases (May 2021) to identify prognostic SR evaluating any risk factor for prosthetic joint infection. We evaluated risk of bias with the ROBIS tool, and methodological quality with a modified AMSTAR-2 tool. We computed the overlap degree study between included SR. RESULTS: Twenty-three SR were included, studying 15 factors for prosthetic joint infection, of which, 13 had significant association. The most frequently studied risk factors were obesity, intra-articular corticosteroids, smoking and uncontrolled diabetes. Overlapping between SR was high for obesity and very high for intra-articular corticoid injection, smoking and uncontrolled diabetes. Risk of bias was considered low in 8SRs (34.7%). The modified AMSTAR-2 tool showed important methodological gaps. CONCLUSIONS: Identification of procedural-modifiable factors, such as intra-articular corticoids use, can give patients better results. Overlapping between SR was very high, meaning that some SR are redundant. The evidence on risk factors for prosthetic joint infection is weak due to high risk of bias and limited methodological quality.
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Polymer nanoclay composites have received significant attention due to their substantially enhanced mechanical, thermal and barrier properties. However, the effect of these nanoclays on the dynamic fracture resistance of a polymer matrix during fast fracture events has not been documented. In this study, the effect of nanoclay addition on the rapid crack propagation (RCP) resistance of high-density polyethylene (HDPE) was investigated through the high-speed double torsion test. Results showed that the addition of 1, 3, and 5% of nanoclays improved the dynamic fracture resistance under the plane strain conditions (Gd1) of HDPE up to 65%. An increase in the storage and loss modulus, and a decrease in crystallinity and melt flow index with nanoclay content was also found. Although the presence of agglomerates can hinder the enhancement of Gd1 as it promotes agglomerate fracture and debonding, the increase in energy consumption through fibrillation and crazing promoted by the nanoclay prevails, suggesting that the nanoclay's toughening effect that has been extensively reported under quasi-static and impact tests, is also present under RCP conditions, and that the HDPE nanocomposites could be used in applications in which RCP must be prevented.
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A theoretical analysis of optical properties in a ZnS/CdS/ZnS core/shell/shell spherical quantum dot was carried out within the effective mass approximation. The corresponding Schrödinger equation was solved using the finite element method via the 2D axis-symmetric module of COMSOL-Multiphysics software. Calculations included variations of internal dot radius, the application of electric and magnetic fields (both oriented along z-direction), as well as the presence of on-center donor impurity. Reported optical properties are the absorption and relative refractive index change coefficients. These quantities are related to transitions between the ground and first excited states, with linearly polarized incident radiation along the z-axis. It is found that transition energy decreases with the growth of internal radius, thus causing the red-shift of resonant peaks. The same happens when the external magnetic field increases. When the strength of applied electric field is increased, the opposite effect is observed, since there is a blue-shift of resonances. However, dipole matrix moments decrease drastically with the increase of the electric field, leading to a reduction in amplitude of optical responses. At the moment impurity effects are activated, a decrease in the value of the energies is noted, significantly affecting the ground state, which is more evident for small internal radius. This is reflected in an increase in transition energies.
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OBJECTIVES: Determine the association of higher FI-LAB scores, derived from common laboratory values and vital signs, with hospital and post-hospital outcomes in Veterans hospitalized with COVID-19 infection. DESIGN, SETTING, AND PARTICIPANTS: A retrospective, multicenter, cohort study of 7 Veterans Health Administration (VHA) medical centers in Florida and Puerto Rico. Patients aged 18 years and older hospitalized with COVID-19 and followed for up to 1 year post discharge or until death. Clinical Frailty Measure: FI-LAB. MAIN OUTCOMES AND MEASURES: Hospital and post-hospital outcomes. RESULTS: Of the 671 eligible patients, 615 (91.5%) patients were included (mean [SD] age, 66.1 [14.8] years; 577 men [93.8%]; median stay, 8 days [IQR:3-15]. There were sixty-one in-hospital deaths. Veterans in the moderate and high FI-LAB groups had a higher proportion of inpatient mortality (13.3% and 20.6%, respectively) than the low group (4.1%), p <0.001. Moderate and high FI-LAB scores were associated with greater inpatient mortality when compared to the low group, OR:3.22 (95%CI:1.59-6.54), p=.001 and 6.05 (95%CI:2.48-14.74), p<0.001, respectively. Compared with low FI-LAB scores, moderate and high scores were also associated with prolonged length of stay, intensive care unit (ICU) admission, and transfer. CONCLUSIONS AND RELEVANCE: In this study of patients admitted to 7 VHA Hospitals during the first surge of the pandemic, higher FI-LAB scores were associated with higher in-hospital mortality and other in-hospital outcomes; FI-LAB can serve as a validated, rapid, feasible, and objective frailty tool in hospitalized adults with COVID-19 that can aid clinical care.