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1.
Rehabilitación (Madr., Ed. impr.) ; 58(2): 1-14, abril-junio 2024. tab
Artigo em Espanhol | IBECS | ID: ibc-232118

RESUMO

La pandemia de COVID-19 ha afectado a la población, perjudicando especialmente a los miembros de aquellos grupos sociales en situación de mayor vulnerabilidad. Estas poblaciones específicas, como aquellas con alguna dependencia funcional, podrían verse más afectadas por los efectos de la pandemia del COVID-19. Por lo tanto, el objetivo de este artículo fue describir las intervenciones para preservar la salud general, mantener la función y la independencia y prevenir la infección por COVID-19 para los adultos con dependencia funcional (ADF). Se realizó una búsqueda sistemática en bases de datos. Se revisaron los títulos y los resúmenes de cada publicación para determinar su relevancia. Dos revisores independientes accedieron a los artículos de texto completo para determinar su elegibilidad después de la selección inicial. Las búsquedas se realizaron en septiembre de 2021 y se actualizaron en enero y julio de 2022. La información encontrada se clasificó en 3 categorías: 1) ADF durante la pandemia de COVID-19; 2) ADF durante la pandemia de COVID-19 según una condición específica (condiciones neurológicas, discapacidades/deficiencias sensoriales y deterioro cognitivo), y 3) Adultos mayores con dependencia funcional. Los adultos con dependencia enfrentaron dificultades y barreras durante la pandemia por COVID-19. Las autoridades de cada país deben garantizar que los ADF tengan acceso a los servicios de rehabilitación en tiempos de crisis sanitaria. Además, es necesario aumentar la capacidad de los servicios de rehabilitación en tiempos de crisis como pandemias. De igual manera, se sugiere el fortalecimiento de estrategias como la telerehabilitación para evitar el deterioro o agravamiento de la funcionalidad de las personas dependientes. (AU)


The COVID-19 pandemic has affected the world population, especially people from social groups in a situation of greater vulnerability among people with some functional dependency. Therefore, the aim of this review was to describe interventions during the pandemic to preserve general health, maintain function and independence, and prevent COVID-19 infection for functionally dependent adults (FDA). A systematic search in databases was carried out. Titles and abstracts of each publication were reviewed for relevance. Full-text articles were accessed by two independent reviewers. The information found was classified into three categories: 1) FDA during the COVID-19 pandemic, 2) FDA during the COVID-19 pandemic according to a specific condition (neurological conditions, sensory disabilities/impairments, and cognitive impairment), and 3) Older adults with functional dependence. The FDAs have faced difficulties and barriers during the COVID-19 pandemic. Strengthening strategies such as telerehabilitation is suggested to avoid deterioration or aggravation of the functionality of dependent people. (AU)


Assuntos
Humanos , Atividades Cotidianas , Vida Independente , Moradias Assistidas , Envelhecimento , Cuidadores
2.
Braz J Biol ; 84: e276871, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38451630

RESUMO

The objective of the study was to carry out phytochemical prospection through colorimetric tests to determine the groups of secondary metabolites and also to determine the total content of phenolic compounds (TPC) present in plant extracts methanol (ME), ethyl acetate (EAE), hexane (HE) and dichloromethane (DE) from the leaves of Myrsine umbellata, as well as to investigate the antimicrobial activity against twelve standard ATCC strains by the broth microdilution technique; the antioxidant potential by the DPPH method and the ABTS method and the antibiofilm potential on the biofilm biomass of standard bacteria by the crystal violet technique and tetrazolium salt reduction (MTT) assay. Phytochemical prospection detected the presence of saponins, steroids, alkaloids, anthocyanins, anthocyanidins, flavonoids, and tannins. The results of the quantitative phytochemical estimation revealed a higher content of total phenolics in DE (280.24 ± 0.037 µM GAE g ext. -1) followed by ME (159.01 ± 0.031 µM GAE g ext. -1). The ME showed the best biological activities when compared to the other extracts tested. We observed antimicrobial activity against Gram-positive Staphylococcus epidermidis strain (MIC 3.12 and MBC 6.25), antioxidant percentage of 92.58% against the DPPH radical and 420.31 µM Trolox g ext. -1 against the ABTS radical, finally showed antibiofilm action against Gram-positive strain Staphylococcus aureus, with eradication of the biomass in 92.58%. The results suggest that EM from M. umbellata represents an alternative source of plant bioactives for the development of natura products.


Assuntos
Anti-Infecciosos , Benzotiazóis , Myrsine , Ácidos Sulfônicos , Antocianinas , Antioxidantes/farmacologia , Metanol , Fenóis/farmacologia , Compostos Fitoquímicos/farmacologia , Anti-Infecciosos/farmacologia
3.
Pharmacol Res ; 202: 107130, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38447748

RESUMO

Pharmacology has broadened its scope considerably in recent decades. Initially, it was of interest to chemists, doctors and pharmacists. In recent years, however, it has been incorporated into the teaching of biologists, molecular biologists, biotechnologists, chemical engineers and many health professionals, among others. Traditional teaching methods, such as lectures or laboratory work, have been superseded by the use of new pedagogical approaches to enable a better conceptualization and understanding of the discipline. In this article, we present several new methods that have been used in Spanish universities. Firstly, we describe a teaching network that has allowed the sharing of pedagogical innovations in Spanish universities. A European experience to improve prescribing safety is described in detail. The use of popular films and medical TV series in biomedical students shows how these audiovisual resources can be helpful in teaching pharmacology. The use of virtual worlds is detailed to introduce this new approach to teaching. The increasingly important area of the social aspects of pharmacology is also considered in two sections, one devoted to social pharmacology and the other to the use of learning based on social services to improve understanding of this important area. Finally, the use of Objective Structured Clinical Evaluation in pharmacology allows to know how this approach can help to better evaluate clinical pharmacology students. In conclusion, this article allows to know new pedagogical methods resources used in some Spanish universities that may help to improve the teaching of pharmacology.


Assuntos
Farmacologia Clínica , Farmacologia , Humanos , Aprendizagem , Farmacologia Clínica/educação , Pessoal de Saúde , Farmacologia/educação
4.
Food Res Int ; 176: 113863, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38163679

RESUMO

Yacon is a highly perishable tuberous root, rich in fructooligosaccharides (FOS). Convective drying preceded by ethanol treatment (ET) is an alternative for increasing shelf life in a shorter process. The aim of this study was to investigate the impact of ET and temperature (50 °C and 70 °C) on quality parameters (fructan retention, total phenolic content, antioxidant capacity, shrinkage, color and microstructural parameters) and process parameters (drying time, drying kinetics, and energy consumption) in the convective drying of yacon slices. The ET induced structural alterations in the tissues and cells that aids in the reduction of drying time up to 28.00 %. ET resulted in an increase in effective diffusivity and leaded to noteworthy reduction in energy consumption (up to 22.72 %). The quality parameters such as color, shrinkage, and total phenolic content showed no significant differences among the treatments. The use of ethanol promoted highest preservation of antioxidant activity; however, it caused degradation of FOS. The ethanol pretreated drying at 50 °C was the better condition for lower consumption and preservation of quality parameters as total phenolic content, antioxidant capacity and fructan retention, but the samples dried at 50 °C were the ones with the highest fructan retention (55.11 ± 2.19 %).


Assuntos
Antioxidantes , Etanol , Antioxidantes/química , Fenóis/química , Dessecação/métodos , Frutanos
5.
Rehabilitacion (Madr) ; 58(2): 100827, 2024.
Artigo em Espanhol | MEDLINE | ID: mdl-38160494

RESUMO

The COVID-19 pandemic has affected the world population, especially people from social groups in a situation of greater vulnerability among people with some functional dependency. Therefore, the aim of this review was to describe interventions during the pandemic to preserve general health, maintain function and independence, and prevent COVID-19 infection for functionally dependent adults (FDA). A systematic search in databases was carried out. Titles and abstracts of each publication were reviewed for relevance. Full-text articles were accessed by two independent reviewers. The information found was classified into three categories: 1) FDA during the COVID-19 pandemic, 2) FDA during the COVID-19 pandemic according to a specific condition (neurological conditions, sensory disabilities/impairments, and cognitive impairment), and 3) Older adults with functional dependence. The FDAs have faced difficulties and barriers during the COVID-19 pandemic. Strengthening strategies such as telerehabilitation is suggested to avoid deterioration or aggravation of the functionality of dependent people.


Assuntos
COVID-19 , Telerreabilitação , Humanos , Idoso , Cuidadores , Pandemias/prevenção & controle , Estado Funcional
6.
Opt Express ; 31(24): 40824-40835, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38041373

RESUMO

The self-healing phenomenon of structured light beams has been comprehensively investigated for its important role in various applications including optical tweezing, superresolution imaging, and optical communication. However, for different structured beams, there are different explanations for the self-healing effect, and a unified theory has not yet been formed. Here we report both theoretically and experimentally a study of the self-healing effect of structured beams in lenslike media, this is, inhomogeneous lenslike media with a quadratic gradient index. By observing the appearance of a number of shadows of obstructed structured wave fields it has been demonstrated that their self-healing in inhomogeneous media are the result of superposition of fundamental traveling waves. We have found that self-healing of structured beams occurs in this medium and, interestingly enough, that the shadows created in the process present sinusoidal propagating characteristics as determined by the geometrical ray theory in lenslike media. This work provides what we believe to be a new inhomogenous environment to explain the self-healing effect and is expected to deepen understanding of the physical mechanism.

7.
Sci Rep ; 13(1): 17965, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37863891

RESUMO

We theoretically propose penta-silicene nanoribbons (p-SiNRs) with induced p-wave superconductivity as a platform for the emergence of spin-polarized Majorana zero-modes (MZMs). The model explicitly considers the key ingredients of well-known Majorana hybrid nanowire setups: Rashba spin-orbit coupling, magnetic field perpendicular to the nanoribbon plane, and first nearest neighbor hopping with p-wave superconducting pairing. The energy spectrum of the system, as a function of chemical potential, reveals the existence of MZMs with a well-defined spin orientation localized at the opposite ends of both the top and bottom chains of the p-SiNR, associated with well-localized and nonoverlapping wave function profiles. Well-established experimental techniques enable the fabrication of highly ordered p-SiNRs, complemented by a thin lead film on top, responsible for inducing p-wave superconductivity through proximity effect. Moreover, the emergence of MZMs with explicit opposite spin orientations for some set of model parameters opens a new avenue for exploring quantum computing operations, which accounts for both MZMs and spin properties, as well as for new MZMs probe devices based on spin-polarized electronic transport mechanisms.

8.
Opt Express ; 31(18): 29196-29212, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710725

RESUMO

Ray tracing in gradient-index (GRIN) media has been thoroughly studied and several ray tracing methods have been proposed. Methods are based on finding the ray path given a known GRIN. In recent decades, the inverse problem, which consists of finding the GRIN distribution for a given light ray path, has been gaining attention. Given that it is not an easy task, the methods proposed in the literature vary in degrees of difficulty. In this work, an alternative method is presented to derive symmetric GRIN distributions whose implementation can be considered the simplest to date. Since it is based on invariants, which result from the symmetries of the system as stated by Fermat's principle, it is an exact numerical method, i.e., the physical system is not approximated. The robustness of the method permits the reconstruction of the GRIN distribution from a ray propagating in three-dimensions. In order to demonstrate its operation, different known symmetric GRIN media are reconstructed using rays that propagate in two and three dimensions.

9.
Med Oral Patol Oral Cir Bucal ; 28(6): e530-e538, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37471300

RESUMO

BACKGROUND: The development and establishment of oral squamous cell carcinoma are confined to carcinogenesis, which involves oxidative stress via oxygen-free radical production as a hydroxyl radical (HO•), considered the most important cause of oxidative damage to basic biomolecules since it targets DNA strands. 8-Hydroxy-2´-deoxyguanosine (8-OHdG) is considered a free radical with a promutagenic capacity due to its ability to pair with adenosine instead of cytosine during replication. MATERIAL AND METHODS: We collected 30 paraffin-embedded tissue samples of OSCC from patients treated between 2013 and 2018. We recorded risk habits, disease stage, disease free survival and death with at least 3 years of follow-up. 8-Hydroxyguanosine was evaluated by immunohistochemistry and subsequently classified as weak-moderate or strong positive expression. Additionally, we noted whether it was expressed in the cytoplasm and/or nucleus. RESULTS: Most of the cases expressed 8-OHdG with a strong intensity (80%). All neoplastic cells were preferentially stained in only the cytoplasm (70.0%), but nuclear positivity was found in 30%, independent of the intensity. Based on the location in the cytoplasm and/or nucleus, tumors >4 cm showed a high frequency (95.5%) of 8-OHdG expression in only the cytoplasm, with a significant difference (p value 0.001). Additionally, overall survival was affected when immunoexpression was present in the cytoplasm and nucleus because all deaths were in this group were statistically significant (p value = 0.001). CONCLUSIONS: All tumors showed DNA oxidative damage, and 8-OHdG was preferentially expressed in the cytoplasm. This finding was associated with tumor size and, when present in the nucleus, might also be related to death.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Bucais , Humanos , 8-Hidroxi-2'-Desoxiguanosina/metabolismo , Desoxiguanosina/química , Desoxiguanosina/metabolismo , Dano ao DNA , Estresse Oxidativo , Radicais Livres
10.
J Helminthol ; 97: e51, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37381606

RESUMO

Mesocestoides is a controversial tapeworm with significant lack of data related to systematics and life cycles. This helminth has an indirect life cycle with vertebrates, mostly carnivorous mammals, as definitive hosts. Theoretically, a coprophagous arthropod would be the first intermediate host, and herptiles, mammals, and birds, which prey on these insects, would represent the second intermediate hosts. However, recent evidence suggests that this life cycle would require only two hosts, with no arthropods involved. In the Neotropics, although there are records of mammals and reptiles as hosts for Mescocestoides, no molecular analyses have been performed. This work aimed to record an additional intermediate host and molecularly characterize the isolated larvae. Thus, 18 braided tree iguanas (Liolaemus platei) from Northern Chile were collected and dissected during 2019. One lizard was parasitized by three morphotypes of larvae compatible with tetrathyridia of Mescocestoides. To achieve its specific identity, a molecular approach was performed: 18S rRNA and 12S rRNA loci were amplified through cPCR. The inferred phylogenies confirmed the morphological diagnosis and stated that all morphotypes were conspecifics. The sequences for both loci formed a monophyletic clade with high nodal support, representing a sister taxon to Mescocestoides clade C. This study represents the first molecular characterization of any taxon of Mescocestoides from the Neotropics. Future surveys from potential definitive hosts would help to elucidate its life cycle. Furthermore, an integrative taxonomic approach is required in additional studies from the Neotropical region, which would contribute to a better understanding of the evolutionary relationships of this genus.


Assuntos
Lagartos , Animais , Chile/epidemiologia , Evolução Biológica , Larva/genética , RNA Ribossômico 18S , Mamíferos
11.
Artigo em Inglês | MEDLINE | ID: mdl-37164796

RESUMO

INTRODUCTION AND AIM: A large number of patients with autoimmune hepatitis (AH) seek information about their disease on the Internet. The reliability, comprehensiveness, and quality of said information in Spanish has not been studied. Our aim was to describe the characteristics of the information about AH on YouTube®. METHODS: An analytic observational study evaluated videos in Spanish about AH available on YouTube®, describing their general characteristics, viewer engagement, and information sources. Standardized tools were utilized to analyze reliability (DISCERN), comprehensiveness, and overall quality (Global Quality Score [GQS]). RESULTS: One hundred videos were included, 93% of which provided information from healthcare professionals (group 1), and 7% of which reflected patient opinions (group 2). There were differences in the median reliability (DISCERN 4 vs 2, p ≤ 0.05) and comprehensiveness (4 vs 2, p ≤ 0.05) scores between groups, but equal overall quality (GQS 3 vs 2, p = 0.2). Reliability (DISCERN 4; RIC 3-4) and comprehensiveness (4.5; IQR 3-5) were higher in videos by professional organizations, compared with those by independent users, healthcare information websites, and for-profit organizations (DISCERN 3; IQR 2.5-3.5) (p < 0.001). Reliability (DISCERN 2; IQR 1.5-3), comprehensiveness (2; IQR 1.5-2.5), and quality (GQS 2.5; IQR 1.5-3.5) were lower for videos made by for-profit organizations. CONCLUSION: The majority of videos about AH in Spanish on YouTube® have good reliability, comprehensiveness, and quality. Videos created by academic organizations had higher scores, thus their collaboration, with respect to patient opinion videos, is suggested.

12.
Artigo em Inglês | MEDLINE | ID: mdl-37164798

RESUMO

INTRODUCTION AND AIM: The majority of patients with inflammatory bowel disease (IBD) seek information about their disease on the Internet. The reliability, comprehensiveness, and quality of said information in Spanish has not previously been studied. MATERIALS AND METHODS: An analytic observational study was conducted that included YouTube® videos on IBD available in Spanish, describing general characteristics, engagement, and sources. Standard tools for evaluating reliability (DISCERN), comprehensiveness, and overall quality (Global Quality Score, GQS) were employed. RESULTS: One hundred videos were included. Eighty-eight videos consisted of information produced by healthcare professionals (group 1) and 12 included patient opinions (group 2). There were no differences in the median scores for reliability (DISCERN 3 vs 3, p = 0.554) or comprehensiveness (3 vs 2.5, p = 0.768) between the two groups, but there was greater overall quality in the group 2 videos (GQS 3 vs 4, p = 0.007). Reliability was higher for the videos produced by professional organizations (DISCERN 4; IQR 3-4), when compared with healthcare information websites and for-profit agencies (DISCERN 3; IQR 2.5-3.5) (p < 0.001), but the videos with healthcare information website and for-profit sources had a higher quality score (GQS 3 vs 4, p < 0.001). Comprehensiveness scores were similar. CONCLUSION: The majority of YouTube® videos in Spanish on IBD have good reliability, comprehensiveness, and quality. Reliability was greater for the videos produced by professional organizations, whereas quality was higher for those created from healthcare information websites and for-profit agencies.

13.
Microbiol Spectr ; 11(3): e0454022, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37010409

RESUMO

Osteomyelitis is an infection of the bone, associated with an inflammatory process. Imaging plays an important role in establishing the diagnosis and the most appropriate patient management. However, data are lacking regarding the use of preclinical molecular imaging techniques to assess osteomyelitis progression in experimental models. This study aimed to compare structural and molecular imaging to assess disease progression in a mouse model of implant-related bone and joint infections caused by Staphylococcus aureus. In SWISS mice, the right femur was implanted with a resorbable filament impregnated with S. aureus (infected group, n = 10) or sterile culture medium (uninfected group, n = 6). Eight animals (5 infected, 3 uninfected) were analyzed with magnetic resonance imaging (MRI) at 1, 2, and 3 weeks postintervention, and 8 mice were analyzed with [18F]fluorodeoxyglucose (FDG)-positron emission tomography (PET)-computed tomography (CT) at 48 h and at 1, 2, and 3 weeks postintervention. In infected animals, CT showed bone lesion progression, mainly in the distal epiphysis, although some uninfected animals presented evident bone sequestra at 3 weeks. MRI showed a lesion in the articular area that persisted for 3 weeks in infected animals. This lesion was smaller and less evident in the uninfected group. At 48 h postintervention, FDG-PET showed higher joint uptake in the infected group than in the uninfected group (P = 0.025). Over time, the difference between groups increased. These results indicate that FDG-PET imaging was much more sensitive than MRI and CT for differentiating between infection and inflammation at early stages. FDG-PET clearly distinguished between infection and postsurgical bone healing (in uninfected animals) from 48 h to 3 weeks after implantation. IMPORTANCE Our results encourage future investigations on the utility of the model for testing different therapeutic procedures for osteomyelitis.


Assuntos
Osteomielite , Infecções Estafilocócicas , Animais , Camundongos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18 , Staphylococcus aureus , Infecções Estafilocócicas/diagnóstico por imagem , Osteomielite/diagnóstico por imagem , Imageamento por Ressonância Magnética
14.
Int. j. clin. health psychol. (Internet) ; 23(2): 1-9, abr.-jun. 2023. tab, graf, ilus
Artigo em Inglês | IBECS | ID: ibc-213891

RESUMO

Background/Objective: Screening for depression in patients with cancer can be difficult due to overlap between symptoms of depression and cancer. We assessed validity of the Beck Depression Inventory (BDI-II) in this population. Method: Data was obtained in an outpatient neuropsychiatry unit treating patients with and without cancer. Psychometric properties of the BDI-II Portuguese version were assessed separately in 202 patients with cancer, and 376 outpatients with mental health complaints but without cancer. Results: Confirmatory factor analysis suggested a three-factor structure model (cognitive, affective and somatic) provided best fit to data in both samples. Criterion validity was good for detecting depression in oncological patients, with an area under the ROC curve (AUC) of 0.85 (95% confidence interval [CI], 0.76–0.91). A cut-off score of 14 had sensitivity of 87% and specificity of 73%. Excluding somatic items did not significantly change the ROC curve for BDI-II (difference AUCs = 0.002, p=0.9). A good criterion validity for BDI-II was also obtained in the non-oncological population (AUC = 0.87; 95% CI 0.81–0.91), with a cut-off of 18 (sensitivity=84%; specificity=73%). Conclusions: The BDI-II demonstrated good psychometric properties in patients with cancer, comparable to a population without cancer. Exclusion of somatic items did not affect screening accuracy. (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Neoplasias/psicologia , Depressão , Psicometria , Análise Fatorial , Curva ROC , Inquéritos e Questionários , Portugal
15.
Artigo em Inglês | MEDLINE | ID: mdl-36973121

RESUMO

INTRODUCTION AND AIMS: Distal pancreatectomy is a frequent procedure and postoperative fistula, its most common complication, has an incidence of 30 to 60%. The aim of the present work was to study the role of the neutrophil-to-lymphocyte ratio and the platelet-to-lymphocyte ratio, as indicators of inflammatory response in the setting of pancreatic fistula. METHODS: A retrospective observational study was conducted on patients that underwent distal pancreatectomy. The diagnosis of postoperative pancreatic fistula was made according to the definition proposed by the International Study Group on Pancreatic Fistula. The relation of postoperative pancreatic fistula to the neutrophil-to-lymphocyte ratio and the platelet-to-lymphocyte ratio was determined in the postoperative evaluation. SPSS v.21 software was utilized for the statistical analysis and a P<.05 was considered statistically significant. RESULTS: A total of 12 patients (27.2%) developed grade B or grade C postoperative pancreatic fistula. ROC curves were constructed and a threshold of 8.3 (PPV 0.40, NPV 0.86) was established for the neutrophil-to-lymphocyte ratio, with an area under the curve of 0.71, sensitivity of 0.81, and specificity of 0.62, whereas a threshold of 33.2 (PPV 0.50, NPV 0.84) was established for the platelet-to-lymphocyte ratio, with an area under the curve of 0.72, sensitivity of 0.72, and specificity of 0.71. CONCLUSION: The neutrophil-to-lymphocyte ratio and the platelet-to-lymphocyte ratio are serologic markers that can aid in identifying patients that will present with grade B or grade C postoperative pancreatic fistula, thus helping to provide an opportune focus on care and resources.

16.
Sci Rep ; 13(1): 1508, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36707603

RESUMO

Topological one-dimensional superconductors can sustain zero energy modes protected by different kinds of symmetries in their extremities. Observing these excitations in the form of Majorana fermions is one of the most intensive quests in condensed matter physics. We are interested in another class of one-dimensional topological systems in this work, namely topological insulators. Which present symmetry-protected end modes with robust properties and do not require the low temperatures necessary for topological superconductivity. We consider a device in the form of a single electron transistor coupled to the simplest kind of topological insulators, namely chains of atoms with hybridized sp orbitals. We study the thermoelectric properties of the device in the trivial, non-trivial topological phases and at the quantum topological transition of the chains. We show that the device's electrical conductance and the Wiedemann-Franz ratio at the topological transition have universal values at very low temperatures. The conductance and thermopower of the device with diatomic sp-chains, at their topological transition, give direct evidence of fractional charges in the system. The former has an anomalous low-temperature behavior, attaining a universal value that is a consequence of the double degeneracy of the system due to the presence of zero energy modes. On the other hand, the system can be tuned to exhibit high values of the thermoelectric figure of merit and the power factor at high temperatures.

17.
J Synchrotron Radiat ; 30(Pt 1): 242-250, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36601943

RESUMO

The PERCIVAL detector is a CMOS imager designed for the soft X-ray regime at photon sources. Although still in its final development phase, it has recently seen its first user experiments: ptychography at a free-electron laser, holographic imaging at a storage ring and preliminary tests on X-ray photon correlation spectroscopy. The detector performed remarkably well in terms of spatial resolution achievable in the sample plane, owing to its small pixel size, large active area and very large dynamic range; but also in terms of its frame rate, which is significantly faster than traditional CCDs. In particular, it is the combination of these features which makes PERCIVAL an attractive option for soft X-ray science.


Assuntos
Fótons , Radiografia , Raios X
18.
J Autism Dev Disord ; 53(8): 3012-3022, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35616819

RESUMO

This study examines declarative memory retrieval in ASD depending on the availability and access to stored conceptual knowledge. Fifteen autistic participants and a matched control group of 18 typically-developed (TD) volunteers completed a Remember-Know paradigm manipulated by encoding-type (categorical, perceptual) and item-typicality (high-typical, low-typical). The autistic group showed worse and slower recognition and less recollection but equivalent familiarity-based memories compared to TDs. Notably, low-typical items did not improve their memories as they did for TDs, likely due to difficulties in matching low-fit information to the stored schema. Results suggest that memory decline in ASD may derive from the episodic system and its dynamics with the semantic system. These findings may inform interventional strategies for enhancing learning abilities in ASD.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Memória Episódica , Humanos , Rememoração Mental , Reconhecimento Psicológico
19.
Food Chem ; 402: 134472, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36303384

RESUMO

An efficient macroporous resin purification process was designed to obtain food-grade phlorotannin-rich extracts from the seaweeds Durvillaea incurvata and Lessonia spicata. Phlorotannins were profiled to relate structures with the α-glucosidase inhibitory activity of the extracts. Liquid chromatography-mass spectrometry was applied for tentative identification. The best phlorotannin purification performance was achieved with HP-20 resin and elution with 80% v/v ethanol. This is the first study that demonstrates the effectivity of HP-20 resin for removing potentially toxic elements (As, Cd) from seaweed extracts. Fucols/phlorethols/fucophlorethols isomers up to 4 phloroglucinol units (PGU) were the most representative phlorotannins. High molecular weight species (11-21 PGU), although in low abundances, were detected in D. incurvata for the first time. Eckols, carmalols, fuhalols, phenolic acids, and flavonoids were also detected. Some extracts' potent α-glucosidase inhibitory activities were related to their high phlorotannin abundances, the presence of phlorotannins of a high degree of polymerization, and the phlorotannins class.


Assuntos
Alga Marinha , alfa-Glucosidases , Cromatografia Líquida de Alta Pressão/métodos , Taninos/química , Chile , Alga Marinha/química , Floroglucinol/química , Resinas Vegetais
20.
Int J Clin Health Psychol ; 23(2): 100350, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36467263

RESUMO

Background/Objective: Screening for depression in patients with cancer can be difficult due to overlap between symptoms of depression and cancer. We assessed validity of the Beck Depression Inventory (BDI-II) in this population. Method: Data was obtained in an outpatient neuropsychiatry unit treating patients with and without cancer. Psychometric properties of the BDI-II Portuguese version were assessed separately in 202 patients with cancer, and 376 outpatients with mental health complaints but without cancer. Results: Confirmatory factor analysis suggested a three-factor structure model (cognitive, affective and somatic) provided best fit to data in both samples. Criterion validity was good for detecting depression in oncological patients, with an area under the ROC curve (AUC) of 0.85 (95% confidence interval [CI], 0.76-0.91). A cut-off score of 14 had sensitivity of 87% and specificity of 73%. Excluding somatic items did not significantly change the ROC curve for BDI-II (difference AUCs = 0.002, p=0.9). A good criterion validity for BDI-II was also obtained in the non-oncological population (AUC = 0.87; 95% CI 0.81-0.91), with a cut-off of 18 (sensitivity=84%; specificity=73%). Conclusions: The BDI-II demonstrated good psychometric properties in patients with cancer, comparable to a population without cancer. Exclusion of somatic items did not affect screening accuracy.

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