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1.
Proc Natl Acad Sci U S A ; 121(23): e2320012121, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38809713

RESUMO

Rechargeable sodium-oxygen (Na-O2) battery is deemed as a promising high-energy storage device due to the abundant sodium resources and high theoretical energy density (1,108 Wh kg-1). A series of quasisolid electrolytes are constantly being designed to restrain the dendrites growth, the volatile and leaking risks of liquid electrolytes due to the open system of Na-O2 batteries. However, the ticklish problem about low operating current density for quasisolid electrolytes still hasn't been conquered. Herein, we report a rechargeable Na-O2 battery with polyvinylidene fluoride-hexafluoropropylene recombination Nafion (PVDF-HFP@Nafion) based quasisolid polymer electrolyte (QPE) and MXene-based Na anode with gradient sodiophilic structure (M-GSS/Na). QPE displays good flame resistance, locking liquid and hydrophobic properties. The introduction of Nafion can lead to a high Na+ migration number (tNa+ = 0.68) by blocking the motion of anion and promote the formation of NaF-rich solid electrolyte interphase, resulting in excellent cycling stability at relatively high current density under quasisolid environment. In the meantime, the M-GSS/Na anode exhibits excellent dendrite inhibition ability and cycling stability. Therefore, with the synergistic effect of QPE and M-GSS/Na, constructed Na-O2 batteries run more stably and exhibit a low potential gap (0.166 V) after an initial 80 cycles at 1,000 mA g-1 and 1,000 mAh g-1. This work provides the reference basis for building quasisolid state Na-O2 batteries with long-term cycling stability.

2.
Chemistry ; 30(55): e202304106, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39083260

RESUMO

Sodium-oxygen batteries have been regarded as promising energy storage devices due to their low overpotential and high energy density. Its applications, however, still face formidable challenges due to the lack of understanding about the influence of electrocatalysts on the discharge products. Here, a phosphorous and nitrogen dual-doped carbon (PNDC) based cathode is synthesized to increase the electrocatalytic activity and to stabilize the NaO2 superoxide nanoparticle discharge products, leading to enhanced cycling stability when compared to the nitrogen-doped carbon (NDC). The PNDC air cathode exhibits a low overpotential (0.36 V) and long cycling stability (120 cycles). The reversible formation/decomposition and stabilization of the NaO2 discharge products are clearly proven by in-situ synchrotron X-ray diffraction and ex-situ X-ray diffraction. Based on the density functional theory calculation, the PNDC has much stronger adsorption (-2.85 eV) for NaO2 than that of NDC (-1.80 eV), which could efficiently stabilize the NaO2 discharge products.

3.
Sensors (Basel) ; 24(9)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38732904

RESUMO

In this paper, we present a novel approach referred to as the audio-based virtual landmark-based HoloSLAM. This innovative method leverages a single sound source and microphone arrays to estimate the voice-printed speaker's direction. The system allows an autonomous robot equipped with a single microphone array to navigate within indoor environments, interact with specific sound sources, and simultaneously determine its own location while mapping the environment. The proposed method does not require multiple audio sources in the environment nor sensor fusion to extract pertinent information and make accurate sound source estimations. Furthermore, the approach incorporates Robotic Mixed Reality using Microsoft HoloLens to superimpose landmarks, effectively mitigating the audio landmark-related issues of conventional audio-based landmark SLAM, particularly in situations where audio landmarks cannot be discerned, are limited in number, or are completely missing. The paper also evaluates an active speaker detection method, demonstrating its ability to achieve high accuracy in scenarios where audio data are the sole input. Real-time experiments validate the effectiveness of this method, emphasizing its precision and comprehensive mapping capabilities. The results of these experiments showcase the accuracy and efficiency of the proposed system, surpassing the constraints associated with traditional audio-based SLAM techniques, ultimately leading to a more detailed and precise mapping of the robot's surroundings.

4.
Soins Gerontol ; 29(168): 17-20, 2024.
Artigo em Francês | MEDLINE | ID: mdl-38944468

RESUMO

The emergence of social robots in gerontology has introduced new playful and reassuring media into nursing homes and geriatric wards. Despite promising results, their complexity hinders their widespread adoption. The Intelligent Interactive Care System aims to remedy these limitations by offering interactive therapeutic workshops. This study evaluates residents' involvement in these workshops within an adapted activity and care center, revealing a high level of involvement and satisfaction.


Assuntos
Robótica , Humanos , Idoso , Idoso de 80 Anos ou mais , Casas de Saúde , Masculino , Feminino , Melhoria de Qualidade , Geriatria
5.
Beilstein J Org Chem ; 20: 552-560, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505235

RESUMO

A series of novel photo- and ionochromic N-acylated 2-(aminomethylene)benzo[b]thiophene-3(2Н)-ones with a terminal phenanthroline receptor substituent was synthesized. Upon irradiation in acetonitrile or DMSO with light of 436 nm, they underwent Z-E isomerization of the C=C bond, followed by very fast N→O migration of the acyl group and the formation of nonemissive O-acylated isomers. These isomers were isolated preparatively and fully characterized by IR, 1H, and 13C NMR spectroscopy as well as HRMS and XRD methods. The reverse thermal reaction was catalyzed by protonic acids. N-Acylated compounds exclusively with Fe2+ formed nonfluorescent complexes with a contrast naked-eye effect: a color change of the solutions from yellow to dark orange. Subsequent selective interaction with AcO- led to the restoration of the initial absorption and emission properties. Thus, the obtained compounds represent dual-mode "on-off-on" switches of optical and fluorescent properties under sequential exposure to light and H+ or sequential addition of Fe2+ and AcO- ions.

6.
New Phytol ; 237(3): 714-733, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35037253

RESUMO

Tropical forest function is of global significance to climate change responses, and critically determined by water availability patterns. Groundwater is tightly related to soil water through the water table depth (WT), but historically neglected in ecological studies. Shallow WT forests (WT < 5 m) are underrepresented in forest research networks and absent in eddy flux measurements, although they represent c. 50% of the Amazon and are expected to respond differently to global-change-related droughts. We review WT patterns and consequences for plants, emerging results, and advance a conceptual model integrating environment and trait distributions to predict climate change effects. Shallow WT forests have a distinct species composition, with more resource-acquisitive and hydrologically vulnerable trees, shorter canopies and lower biomass than deep WT forests. During 'normal' climatic years, shallow WT forests have higher mortality and lower productivity than deep WT forests, but during moderate droughts mortality is buffered and productivity increases. However, during severe drought, shallow WT forests may be more sensitive due to shallow roots and drought-intolerant traits. Our evidence supports the hypothesis of neglected shallow WT forests being resilient to moderate drought, challenging the prevailing view of widespread negative effects of climate change on Amazonian forests that ignores WT gradients, but predicts they could collapse under very strong droughts.


O funcionamento da floresta tropical é de importância global para as respostas às mudanças climáticas e é criticamente determinado pelos padrões de disponibilidade de água. A água subterrânea está intimamente relacionada à água do solo através da profundidade do lençol freático, que tem sido historicamente negligenciado em estudos ecológicos. Florestas com lençol freático raso (< 5 m) estão sub-representadas nas redes de pesquisa florestal e ausentes nas medições de fluxo de gases, embora representem ~ 50% da Amazônia e devam responder de forma diferente às secas relacionadas às mudanças globais. Aqui revisamos os padrões de profundidade do lençol freático e suas consequências para plantas, resultados emergentes, e avançamos em um modelo conceitual que integra o ambiente e as distribuições de características funcionais para prever os efeitos das mudanças climáticas. As florestas com lençol freático raso têm uma composição de espécies distinta, com árvores mais aquisitivas na obtenção de recursos e hidrologicamente vulneráveis, dosséis mais baixos e menor biomassa do que as florestas com lençol freático profundo. Durante os anos climáticos 'normais', as florestas com lençol freático raso têm maior mortalidade e menor produtividade do que as florestas com lençol freático profundo, mas durante secas moderadas, a mortalidade é amortecida e a produtividade aumenta. No entanto, durante secas severas, as florestas com lençol freático raso podem ser mais sensíveis devido às raízes superficiais e características funcionais de intolerância à seca. Nossas evidências apoiam a hipótese de que as florestas com lençol freático raso, historicamente negligenciadas, sejam resilientes à seca moderada, desafiando a visão predominante dos efeitos negativos generalizados da mudança climática nas florestas amazônicas que ignora gradientes de profundidade do lençol freático, mas prevê que elas podem entrar em colapso sob secas muito fortes.


La función de los bosques tropicales es de importancia mundial para las respuestas al cambio climático y está críticamente determinada por los patrones de disponibilidad de agua. El agua subterránea está estrechamente relacionada con el agua del suelo a través de la profundidad del nivel freático (NF), pero históricamente se há negligenciado en los estudios ecológicos. Los bosques con NF poco profundos (NF < 5 m) están subrepresentados en las redes de investigación forestal y ausentes en las mediciones de flujo de gases, aunque representan ~ 50% de la Amazonía y se espera que respondan de manera diferente a las sequías relacionadas con el cambio climático global. Aquí revisamos los patrones de NF y las consecuencias para las plantas, los resultados emergentes y avanzamos en un modelo conceptual que integra distribuciones ambientales y de rasgos funcionales para predecir los efectos del cambio climático. Los bosques con NF poco profundos tienen una composición de especies distinta, con árboles más adquisitivos en la obtención de recursos e hidrológicamente más vulnerables, dosel más bajo y menor biomasa que los bosques de NF profundo. Durante los años climáticos 'normales', los bosques con NF poco profundos tienen una mayor mortalidad y menor productividad que los bosques con NF profundos, pero durante sequías moderadas la mortalidad se amortigua y la productividad aumenta. Sin embargo, durante una sequía severa, los bosques de NF poco profundos pueden ser más sensibles debido a raíces poco profundas y rasgos de intolerancia a la sequía. Nuestra evidencia apoya la hipótesis de que los bosques de NF poco profundos, mayoritariamente desconsiderados, son resistentes a sequías moderadas, desafiando la visión predominante de impactos negativos generalizados del cambio climático en los bosques amazónicos, que ignora los gradientes de NF, pero predice que podrían colapsar bajo sequías muy fuertes.


Assuntos
Secas , Água Subterrânea , Refúgio de Vida Selvagem , Florestas , Árvores/fisiologia , Mudança Climática , Água , Clima Tropical
7.
Molecules ; 28(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36838917

RESUMO

In this article, we used molecular dynamics (MD), one of the most common methods for simulations of membranes, to study the interaction of fluorescent membranotropic biological probe 10-N-nonyl acridine orange (NAO) with the bilayer, mimicking a plasma membrane of Gram-negative bacteria. Fluorescent probes serve as an effective tool to study the localization of different components in biological membranes. Revealing the molecular details of their interaction with membrane phospholipids is important both for the interpretation of experimental results and future design of lipid-specific stains. By means of coarse-grained (CG) MD, we studied the interactions of NAO with a model membrane, imitating the plasma membrane of Gram-negative bacteria. In our simulations, we detected different NAO forms: monomers, dimers, and stacks. NAO dimers had the central cardiolipin (CL) molecule in a sandwich-like structure. The stacks were formed by NAO molecules interlayered with anionic lipids, predominantly CL. Use of the CG approach allowed to confirm the ability of NAO to bind to both major negatively charged phospholipids, phosphatidylglycerol (PG) and CL, and to shed light on the exact structure of previously proposed NAO-lipid complexes. Thus, CG modeling can be useful for the development of new effective and highly specific molecular probes.


Assuntos
Cardiolipinas , Corantes Fluorescentes , Cardiolipinas/análise , Cardiolipinas/química , Cardiolipinas/metabolismo , Corantes Fluorescentes/química , Laranja de Acridina/química , Fosfatidilgliceróis , Membrana Celular/metabolismo , Fosfolipídeos/metabolismo , Bactérias/metabolismo
8.
Glob Chang Biol ; 28(2): 375-389, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34606660

RESUMO

Phenological mismatch is often cited as a putative driver of population declines in long-distance migratory birds. The mechanisms and cues utilized to advance breeding ground arrival will impact the adaptability of species to further warming. Furthermore, timing of post-breeding migration potentially faces diverging selective pressures, with earlier onset of tropical dry seasons favouring migration advancement, while longer growing seasons in temperate areas could facilitate delayed departures. Despite this, few studies exist of migration phenology on the non-breeding grounds or on post-breeding passage. Here, we use first arrival and last departure dates of 20 species of trans-Saharan migratory birds from tropical non-breeding grounds (The Gambia), between 1964 and 2019. Additionally, we use first arrival and last departure dates, as well as median arrival and departure dates, at an entry/departure site to/from Europe (Gibraltar), between 1991 and 2018. We assess phenological trends in pre- and post-breeding migration, as well as individual species' durations of stay in breeding and non-breeding areas. Furthermore, we assess the extent to which inter-annual variation in these timings may be explained by meteorological and ecological variables. We find significant advances in pre-breeding migration at both locations, while post-breeding migration is delayed. At Gibraltar, these trends do not differ between first/last and median dates of migration. The combination of these trends suggests substantial changes in the temporal usage of the two continents by migratory birds. Duration of stay (of species, not individuals) within Europe increased by 16 days, on average, over the 27-year monitoring period. By contrast, duration of species' stays on the non-breeding range declined by 63 days, on average, over the 56-year monitoring period. Taken together these changes suggest substantial, previously unreported alterations to annual routines in Afro-Palaearctic migrants.


Assuntos
Migração Animal , Aves , África do Norte , Animais , Europa (Continente) , Estações do Ano
9.
Pharmacol Res ; 185: 106489, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36228869

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive cognitive decline and currently there are no available treatments. Alongside the conventional Aß and tau hypotheses, neuroinflammation and metabolism disruption have also been regarded as crucial hallmarks of AD. In this study, a novel Chinese formula Nao Tan Qing (NTQ) was developed and shown to improve AD. In vivo experiments showed that NTQ significantly mitigated cognitive impairment, Aß burden and neuroinflammation in a transgenic AD mouse model (5×FAD). Network pharmacology results revealed that the active components of NTQ could target inflammatory and metabolic pathways. In addition, hippocampal transcriptomics suggested that NTQ regulated signaling pathways related to inflammation and lipid metabolism. Consistently, serum metabolomics further indicated that NTQ could modulate glycolipid metabolism. In summary, a combination of systems pharmacology analysis and biological validation study demonstrates that NTQ could alleviate behavioral abnormality and pathological alterations of AD by targeting glycolipid metabolism and neuroinflammation, and is accordingly a potential therapeutic agent for AD.


Assuntos
Doença de Alzheimer , Animais , Camundongos , Doença de Alzheimer/metabolismo , Doenças Neuroinflamatórias , Farmacologia em Rede , Camundongos Transgênicos , Modelos Animais de Doenças , Metabolismo dos Lipídeos , Glicolipídeos/uso terapêutico , Peptídeos beta-Amiloides/metabolismo
10.
Proc Natl Acad Sci U S A ; 116(6): 1934-1939, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30670639

RESUMO

From early 2003 to mid-2013, the total mass of ice in Greenland declined at a progressively increasing rate. In mid-2013, an abrupt reversal occurred, and very little net ice loss occurred in the next 12-18 months. Gravity Recovery and Climate Experiment (GRACE) and global positioning system (GPS) observations reveal that the spatial patterns of the sustained acceleration and the abrupt deceleration in mass loss are similar. The strongest accelerations tracked the phase of the North Atlantic Oscillation (NAO). The negative phase of the NAO enhances summertime warming and insolation while reducing snowfall, especially in west Greenland, driving surface mass balance (SMB) more negative, as illustrated using the regional climate model MAR. The spatial pattern of accelerating mass changes reflects the geography of NAO-driven shifts in atmospheric forcing and the ice sheet's sensitivity to that forcing. We infer that southwest Greenland will become a major future contributor to sea level rise.

11.
Sensors (Basel) ; 22(3)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35161783

RESUMO

The lack of interest of children at school is one of the biggest problems that Mexican education faces. Two important factors causing this lack of interest are the predominant methodology used in Mexican schools and the technology as a barrier for attention. The methodology that institutions have followed has become an issue because of its very traditional approach, with the professor giving all the theoretical material to the students while they listen and memorize the contents, and, if we add the issue of the growing access to technological devices for students, children carrying a phone are more likely to be distracted. This study aims to integrate technology through assistive robots as a beneficial tool for educators, in order to improve the attention span of students by making the learning process in multiple areas of the Mexican curriculum more dynamic, therefore obtaining better results. To prove this, four different approaches were implemented; three in elementary schools and one in higher education: the LEGO® robotic kit and the NAO robot for STEM (science, technology, engineering, and mathematics) teaching, the NAO robot for physical education (PE), and the PhantomX Hexapod, respectively. Each of these technological approaches was applied by considering both control and experimental groups, in order to compare the data and provide conclusions. Finally, this study proves that the attention span is indeed improved as a result of implementing robotic platforms during the teaching process, allowing the children to become more motivated during their PE class and become more proactive and retain more information during their STEM classes.


Assuntos
Procedimentos Cirúrgicos Robóticos , Robótica , Criança , Países Desenvolvidos , Humanos , Educação Física e Treinamento , Tecnologia
12.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(6): 1189-1198, 2022 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-36575089

RESUMO

Gesture imitation is a common rehabilitation strategy in limb rehabilitation training. In traditional rehabilitation training, patients need to complete training actions under the guidance of rehabilitation physicians. However, due to the limited resources of the hospital, it cannot meet the training and guidance needs of all patients. In this paper, we proposed a following control method based on Kinect and NAO robot for the gesture imitation task in rehabilitation training. The method realized the joint angles mapping from Kinect coordination to NAO robot coordination through inverse kinematics algorithm. Aiming at the deflection angle estimation problem of the elbow joint, a virtual space plane was constructed and realized the accurate estimation of deflection angle. Finally, a comparative experiment for deflection angle of the elbow joint angle was conducted. The experimental results showed that the root mean square error of the angle estimation value of this method in right elbow transverse deflection and vertical deflection directions was 2.734° and 2.159°, respectively. It demonstrates that the method can follow the human movement in real time and stably using the NAO robot to show the rehabilitation training program for patients.


Assuntos
Articulação do Cotovelo , Robótica , Reabilitação do Acidente Vascular Cerebral , Humanos , Extremidade Superior , Robótica/métodos , Reabilitação do Acidente Vascular Cerebral/métodos , Modalidades de Fisioterapia , Fenômenos Biomecânicos
13.
Molecules ; 26(24)2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34946514

RESUMO

Thua-nao, or Thai fermented soybeans, is a traditional Lanna fermented food in Northern Thailand. It is produced by using a specific bacterial species called Bacillus subtilis var. Thua-nao. We investigated the antioxidant activity and cytotoxic effect of isoflavones from Thua-nao. The phenolic compound contents and total flavonoid contents were determined by spectrophotometry. The antioxidant activity was examined using the ABTS, FRAP, and DPPH assays. The isoflavone contents and phenolic compositions were examined by the high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS) techniques. The ability of isoflavones to inhibit human cancer cell growth was assessed by the MTT assay. The total phenolic content, total flavonoid content, and antioxidant activities of the isoflavones were 49.00 ± 0.51 mg GAE/g of dry extract (DE), 10.76 ± 0.82 mg QE/g of DE, 61.03 ± 0.97 µmol Trolox/g of DE, 66.54 ± 3.97 µM FeSO4/g of DE, and 22.47 ± 1.92% of DPPH inhibition, respectively. Additionally, the isoflavone extracts from Thua-nao had high isoflavone contents and polyphenolic compound compositions, especially daidzein and genistein. The isoflavone demonstrated a weak inhibition of MCF-7 and HEK293 cancer cell growth. It has a high antioxidant component, which is beneficial and can be developed for new therapeutic uses. However, further studies on the benefits of Thua-nao should be performed for realizing better and more effective uses soon.


Assuntos
Antioxidantes , Misturas Complexas/química , Citotoxinas , Alimentos Fermentados , Glycine max/química , Isoflavonas , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Citotoxinas/química , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Células HEK293 , Células Hep G2 , Humanos , Isoflavonas/química , Isoflavonas/isolamento & purificação , Isoflavonas/farmacologia , Células MCF-7
14.
Angew Chem Int Ed Engl ; 60(6): 3205-3211, 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33073428

RESUMO

Aprotic Na-O2 batteries have attracted growing interest owing to their low overpotentials and high energy density. Their cycling stability and Coulombic efficiency are limited, however, by Na dendrite formation and superoxide (O2 - ) degradation. Here, we present a bifunctional cation additive, the tetrabutylammonium cation (TBA+ ), to simultaneously protect the Na anode and stabilize the superoxide. The adsorption of TBA+ on the Na anode suppresses the dendrite formation in the Na plating and ensures stable anode cycling at high current density in both Ar and oxygen atmospheres. Aprotic Na-O2 batteries with TBA+ show increased Coulombic efficiency as well as good rate capability. These are rewarded by the fast desolvation kinetics of O2 - and suppression of the disproportionation reaction of O2 - with TBA+ , as confirmed by molecular dynamics simulation and DFT calculations. This bifunctional effect of this cation additive paves a new avenue for the development of Na-O2 batteries.

15.
BMC Health Serv Res ; 20(1): 253, 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32216766

RESUMO

BACKGROUND: Workplace violence against healthcare workers is a global issue that is on the rise, with Chinese healthcare workers facing growing challenges with hospital violence. Attacks on medical staff have increased in recent years with no clear resolution. Prior research focused on policies to improve the doctor-patient relationship and better protect clinicians, but few studies addressed the patient perspective. This paper examines patients' choices when facing a medical dispute and identifies groups who are more likely to respond to conflict with violence or other serious actions. METHODS: Patient survey responses were collected in 12 leading public hospitals in five Chinese provinces with 5556 participants. The survey asked sociodemographic information, patients' attitudes (e.g., general optimism, trust in their physicians, perceived healthcare quality), and their primary response to a medical dispute. From least to most severe, the options range from "complaining within the family" to "violence." We used t-tests and Chi-square tests to explore the relationships between reactions and patient characteristics. We also performed multivariable logistic regressions to determine the impact of sociodemographics and provider trust on the seriousness of responses. RESULTS: The primary response of a third of respondents was complaining to hospital or health department officials (32.5%). Seeking legal help (26.3%) and direct negotiation with doctors (19.6%) were other frequent responses. More serious responses included 83 stating violence (1.5%), 9.7% expressing a desire to expose the issue to the news media, and 7.4% resorting to seeking third-party assistance. Patients who were more likely to report "violence" were male (OR = 1.81, p < .05), high-income earners (OR = 3.71, p < .05), or reported lower life satisfaction (OR = 1.40, p < .05). Higher trust scores were associated with a lower likelihood of a serious response, including violence (OR = 0.80, p < .01). CONCLUSION: Most respondents reported mild reactions when facing a medical dispute. Among those who reported the intent of serious reactions, some sociodemographic characteristics and the trust of physicians could be predictive. To prevent future hospital violence, this work helps identify the characteristics of patients who are more likely to seek severe approaches to medical dispute resolution, including resorting to violence. From these results, hospitals will be better able to target specific groups for interventions that build patient-provider trust and improve general patient satisfaction.


Assuntos
Dissidências e Disputas , Pacientes/psicologia , Relações Médico-Paciente , Violência no Trabalho/estatística & dados numéricos , Adulto , Idoso , China , Feminino , Hospitais Públicos , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes/estatística & dados numéricos , Inquéritos e Questionários , Adulto Jovem
16.
Int J Biometeorol ; 64(4): 611-621, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31900588

RESUMO

Research in northern latitudes confirms that climate teleconnections exert important influences on ungulate fitness, but studies from regions with milder climates are lacking. We explored the influence of the Pacific Decadal Oscillation (PDO), Northern Atlantic Oscillation (NAO), and El Niño-Southern Oscillation (ENSO) on male, 2.5-year-old white-tailed deer (Odocoileus virginianus) antler and body mass in Mississippi, USA, a region with mild winters and warm, humid summers. Explanatory variables were seasonal averages of each climate index extending back to 3 years prior to account for possible maternal and lag effects. Seasonal climate indices from the period of gestation and the first year of life were correlated with deer morphometrics. Reduced antler mass was largely correlated (R2 = 0.52) with PDO values indicating dry conditions during parturition and neonatal development and NAO values indicating warmer than normal winters during gestation and the first year of life. Body mass was less correlated (R2 = 0.16) to climate indices, responding negatively to warmer winter weather during the first winter of life. Climate may promote variable fitness among cohorts through long-term effects on male competition for dominance and breeding access. Because broad-scale climate indices simplify complex weather systems, they may benefit management at larger scales. Although this study compared climate with morphological variables, it is likely that demographic characteristics can likewise be modeled using climate indices. As climate change in this region is projected to include greater variability in summer precipitation, we may see concomitantly greater variability in fitness among cohorts of white-tailed deer.


Assuntos
Chifres de Veado , Cervos , Animais , Mudança Climática , El Niño Oscilação Sul , Masculino , Estações do Ano , Tempo (Meteorologia)
17.
Sensors (Basel) ; 20(22)2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33202827

RESUMO

The effectiveness of social robots such as NAO in pedagogical therapies presents a challenge. There is abundant literature focused on therapies using robots with children with autism, but there is a gap to be filled in other educational different needs. This paper describes an experience of using a NAO as an assistant in a logopedic and pedagogical therapy with children with different needs. Even if the initial robot architecture is based on genericbehaviors, the loading and execution time for each specific requirement and the needs of each child in therapy, made it necessary to develop "Adaptive Behaviors". These evolve into an adaptive architecture, appliedto the engineer-therapist-child interaction, requiring the engineer-programmer to be always present during the sessions. Benefits from the point of view of the therapist and the children and the acceptance of NAO in therapy are shown. A robot in speech-therapy sessions can play a positive role in several logopedic aspectsserving as a motivating factor for the children.Future works should be oriented in developing intelligent algorithms so as to eliminate the presence of the engineer-programmer in the sessions. Additional work proposals should consider deepening the psychological aspects of using humanoid robots in educational therapy.


Assuntos
Tecnologia Educacional , Robótica , Interação Social , Algoritmos , Criança , Humanos
18.
Sensors (Basel) ; 20(13)2020 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-32605077

RESUMO

A Brain-Computer Interface (BCI) acts as a communication mechanism using brain signals to control external devices. The generation of such signals is sometimes independent of the nervous system, such as in Passive BCI. This is majorly beneficial for those who have severe motor disabilities. Traditional BCI systems have been dependent only on brain signals recorded using Electroencephalography (EEG) and have used a rule-based translation algorithm to generate control commands. However, the recent use of multi-sensor data fusion and machine learning-based translation algorithms has improved the accuracy of such systems. This paper discusses various BCI applications such as tele-presence, grasping of objects, navigation, etc. that use multi-sensor fusion and machine learning to control a humanoid robot to perform a desired task. The paper also includes a review of the methods and system design used in the discussed applications.


Assuntos
Interfaces Cérebro-Computador , Aprendizado de Máquina , Algoritmos , Encéfalo/fisiologia , Eletroencefalografia , Humanos , Robótica
19.
Sensors (Basel) ; 20(8)2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32340140

RESUMO

The interaction between humans and an NAO robot using deep convolutional neural networks (CNN) is presented in this paper based on an innovative end-to-end pipeline method that applies two optimized CNNs, one for face recognition (FR) and another one for the facial expression recognition (FER) in order to obtain real-time inference speed for the entire process. Two different models for FR are considered, one known to be very accurate, but has low inference speed (faster region-based convolutional neural network), and one that is not as accurate but has high inference speed (single shot detector convolutional neural network). For emotion recognition transfer learning and fine-tuning of three CNN models (VGG, Inception V3 and ResNet) has been used. The overall results show that single shot detector convolutional neural network (SSD CNN) and faster region-based convolutional neural network (Faster R-CNN) models for face detection share almost the same accuracy: 97.8% for Faster R-CNN on PASCAL visual object classes (PASCAL VOCs) evaluation metrics and 97.42% for SSD Inception. In terms of FER, ResNet obtained the highest training accuracy (90.14%), while the visual geometry group (VGG) network had 87% accuracy and Inception V3 reached 81%. The results show improvements over 10% when using two serialized CNN, instead of using only the FER CNN, while the recent optimization model, called rectified adaptive moment optimization (RAdam), lead to a better generalization and accuracy improvement of 3%-4% on each emotion recognition CNN.


Assuntos
Algoritmos , Expressão Facial , Redes Neurais de Computação , Aprendizado Profundo , Reconhecimento Facial/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Robótica
20.
Sensors (Basel) ; 20(9)2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32349349

RESUMO

In this paper, we propose a novel algorithm to detect a door and its orientation in indoor settings from the view of a social robot equipped with only a monocular camera. The challenge is to achieve this goal with only a 2D image from a monocular camera. The proposed system is designed through the integration of several modules, each of which serves a special purpose. The detection of the door is addressed by training a convolutional neural network (CNN) model on a new dataset for Social Robot Indoor Navigation (SRIN). The direction of the door (from the robot's observation) is achieved by three other modules: Depth module, Pixel-Selection module, and Pixel2Angle module, respectively. We include simulation results and real-time experiments to demonstrate the performance of the algorithm. The outcome of this study could be beneficial in any robotic navigation system for indoor environments.

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