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1.
Opt Lett ; 49(5): 1245-1248, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38426984

RESUMO

We propose a novel (to our knowledge) and simple real-time optical monitoring (RTOM) system for dynamic spectral analysis of telecommunication signals, involving electro-optic (EO) temporal sampling followed by dispersion-induced frequency-to-time mapping and high-speed photodetection. This system enables tracking of the presence and relative intensity of multiple wavelength-division-multiplexed (WDM) data streams that span over a broad frequency band with high resolution, accuracy, and fast measurement update rates. We derive the design conditions and trade-offs of the proposed scheme and report proof-of-concept experiments and a numerical result that demonstrate successful spectral monitoring of dense-WDM signals with different modulation formats and bit rates, over the full C-band, with the needed resolution to discern channels separated by a few tens of GHz, and with an unprecedented fast measurement update rate in the MHz range.

2.
Knee Surg Sports Traumatol Arthrosc ; 32(2): 473-489, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38293728

RESUMO

PURPOSE: One of the most pertinent questions in total knee arthroplasty (TKA) is: what could be considered normal coronal alignment? This study aims to define normal, neutral, deviant and aberrant coronal alignment using large data from a computed tomography (CT)-scan database and previously published phenotypes. METHODS: Coronal alignment parameters from 11,191 knee osteoarthritis (OA) patients were measured based on three dimensional reconstructed CT data using a validated planning software. Based on these measurements, patients' coronal alignment was phenotyped according to the functional knee phenotype concept. These phenotypes represent an alignment variation of the overall hip knee ankle angle (HKA), femoral mechanical angle (FMA) and tibial mechanical angle (TMA). Each phenotype is defined by a specific mean and covers a range of ±1.5° from this mean. Coronal alignment is classified as normal, neutral, deviant and aberrant based on distribution frequency. Mean values and distribution among the phenotypes are presented and compared between two populations (OA patients in this study and non-OA patients from a previously published study). RESULTS: The arithmetic HKA (aHKA), combined normalised data of FMA and TMA, showed that 36.0% of knees were neutral within ±1 SD from the mean in both angles, 44.3% had either a TMA or a FMA within ±1-2 SD (normally aligned), 15.3% of the patients were deviant within ±2-3 SD and only 4.4% of them had an aberrant alignment (±3-4 SD in 3.4% and >4 SD in 1.0% of the patients respectively). However, combining the normalised data of HKA, FMA and TMA, 15.4% of patients were neutral in all three angles, 39.7% were at least normal, 27.7% had at least one deviant angle and 17.2% had at least one aberrant angle. For HKA, the males exhibited 1° varus and females were neutral. For FMA, the females exhibited 0.7° more valgus in mean than males and grew 1.8° per category (males grew 2.1° per category). For TMA, the males exhibited 1.3° more varus than females and both grew 2.3° and 2.4° (females) per category. Normal coronal alignment was 179.2° ± 2.8-5.6° (males) and 180.5 > ± 2.8-5.6° (females) for HKA, 93.1 > ± 2.1-4.2° (males) and 93.8 > ± 1.8-3.6° (females) for FMA and 86.7 > ± 2.3-4.6° (males) and 88 > ± 2.4-4.8° (females) for TMA. This means HKA 6.4 varus or 4.8° valgus (males) or 5.1° varus to 6.1° valgus was considered normal. For FMA HKA 1.1 varus or 7.3° valgus (males) or 0.2° valgus to 7.4° valgus was considered normal. For TMA HKA 7.9 varus or 1.3° valgus (males) or 6.8° varus to 2.8° valgus was considered normal. Aberrant coronal alignment started from 179.2° ± 8.4° (males) and 180.5 > ± 8.4° (females) for HKA, 93.1 > ± 6.3° (males) 93.8 > ± 5.4° (females) for FMA and 86.7 > ± 6.9° (males) and 88 > ± 7.2° (females) for TMA. This means HKA > 9.2° varus or 7.6° valgus (males) or 7.9° varus to 8.9° valgus was considered aberrant. CONCLUSION: Definitions of neutrality, normality, deviance as well as aberrance for coronal alignment in TKA were proposed in this study according to their distribution frequencies. This can be seen as an important first step towards a safe transition from the conventional one-size-fits-all to a more personalised coronal alignment target. There should be further definitions combining bony alignment, joint surfaces' morphology, soft tissue laxities and joint kinematics. LEVEL OF EVIDENCE: III.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Masculino , Feminino , Humanos , Artroplastia do Joelho/métodos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Extremidade Inferior , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Fêmur/cirurgia , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/cirurgia , Estudos Retrospectivos
3.
Sensors (Basel) ; 24(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38732843

RESUMO

As the number of electronic gadgets in our daily lives is increasing and most of them require some kind of human interaction, this demands innovative, convenient input methods. There are limitations to state-of-the-art (SotA) ultrasound-based hand gesture recognition (HGR) systems in terms of robustness and accuracy. This research presents a novel machine learning (ML)-based end-to-end solution for hand gesture recognition with low-cost micro-electromechanical (MEMS) system ultrasonic transducers. In contrast to prior methods, our ML model processes the raw echo samples directly instead of using pre-processed data. Consequently, the processing flow presented in this work leaves it to the ML model to extract the important information from the echo data. The success of this approach is demonstrated as follows. Four MEMS ultrasonic transducers are placed in three different geometrical arrangements. For each arrangement, different types of ML models are optimized and benchmarked on datasets acquired with the presented custom hardware (HW): convolutional neural networks (CNNs), gated recurrent units (GRUs), long short-term memory (LSTM), vision transformer (ViT), and cross-attention multi-scale vision transformer (CrossViT). The three last-mentioned ML models reached more than 88% accuracy. The most important innovation described in this research paper is that we were able to demonstrate that little pre-processing is necessary to obtain high accuracy in ultrasonic HGR for several arrangements of cost-effective and low-power MEMS ultrasonic transducer arrays. Even the computationally intensive Fourier transform can be omitted. The presented approach is further compared to HGR systems using other sensor types such as vision, WiFi, radar, and state-of-the-art ultrasound-based HGR systems. Direct processing of the sensor signals by a compact model makes ultrasonic hand gesture recognition a true low-cost and power-efficient input method.


Assuntos
Gestos , Mãos , Aprendizado de Máquina , Redes Neurais de Computação , Humanos , Mãos/fisiologia , Reconhecimento Automatizado de Padrão/métodos , Ultrassonografia/métodos , Ultrassonografia/instrumentação , Ultrassom/instrumentação , Algoritmos
4.
Int Nurs Rev ; 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38197742

RESUMO

AIM: To identify current key areas for nursing research in Switzerland, we revised the Swiss Research Agenda for Nursing (SRAN) initially published in 2008. BACKGROUND: By developing a research agenda, nursing researchers internationally prioritize and cluster relevant topics within the research community. The process should be collaborative and systematic to provide credible information for decisionmakers in health care research, policy, and practice. SOURCES OF EVIDENCE: After a participative, systematic, and critical evaluation within and outside of the Swiss Association for Nursing Science, the updated SRAN 2019-2029 defines four research priorities (new models of care, nursing care interventions, work and care environment, and quality of care and patient safety) and four transversal themes (organization of research, research methodologies, research in health care policy and public health perspectives). CONCLUSION: Adding to other national nursing research agendas, the categories are organized in a framework of key research priorities and transversal themes. They relate to the importance of global and local foci of research as well as challenges in health care services and policy systems. The agenda is an important prerequisite for enhancing the influence of nursing research in Switzerland and provides guidance for the next decade. IMPLICATIONS FOR NURSING PRACTICE: The revised agenda ensures that research projects target key knowledge gaps and the discipline's core questions in respective countries. IMPLICATIONS FOR HEALTH POLICY: Nursing research should inform and influence health policy on all institutional and political levels. Therefore, the integration of public health perspectives in research is one of the most important new aspects of SRAN 2019-2029.

5.
Nat Mater ; 21(4): 416-422, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34969994

RESUMO

Disordered magnetic states known as spin liquids are of paramount importance in both fundamental and applied science. A classical state of this kind was predicted for the Ising antiferromagnetic triangular model, while additional non-commuting exchange terms were proposed to induce its quantum version-a quantum spin liquid. However, these predictions have not yet been confirmed experimentally. Here, we report evidence for such a state in the triangular-lattice antiferromagnet NdTa7O19. We determine its magnetic ground state, which is characterized by effective spin-1/2 degrees of freedom with Ising-like nearest-neighbour correlations and gives rise to spin excitations persisting down to the lowest accessible temperature of 40 mK. Our study demonstrates the key role of strong spin-orbit coupling in stabilizing spin liquids that result from magnetic anisotropy and highlights the large family of rare-earth (RE) heptatantalates RETa7O19 as a framework for realization of these states, which represent a promising platform for quantum applications.

6.
Phys Rev Lett ; 130(16): 166703, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37154642

RESUMO

Spiral spin liquids are an exotic class of correlated paramagnets with an enigmatic magnetic ground state composed of a degenerate manifold of fluctuating spin spirals. Experimental realizations of the spiral spin liquid are scarce, mainly due to the prominence of structural distortions in candidate materials that can trigger order-by-disorder transitions to more conventionally ordered magnetic ground states. Expanding the pool of candidate materials that may host a spiral spin liquid is therefore crucial to realizing this novel magnetic ground state and understanding its robustness against perturbations that arise in real materials. Here, we show that the material LiYbO_{2} is the first experimental realization of a spiral spin liquid predicted to emerge from the J_{1}-J_{2} Heisenberg model on an elongated diamond lattice. Through a complementary combination of high-resolution and diffuse neutron magnetic scattering studies on a polycrystalline sample, we demonstrate that LiYbO_{2} fulfills the requirements for the experimental realization of the spiral spin liquid and reconstruct single-crystal diffuse neutron magnetic scattering maps that reveal continuous spiral spin contours-a characteristic experimental hallmark of this exotic magnetic phase.

7.
Prev Med ; 170: 107492, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37001605

RESUMO

This study is to identify victimization patterns and analyze the association between the experience of polyvictimization and overweight or obesity among adolescent girls and boys. The sample consisted of 2680 Brazilian ninth-graders enrolled in public and private schools, taken from the São Paulo Project for the social development of children and adolescents (SP-PROSO). Victimization was explored in two ways: (i) as per Finkelhor and (ii) by latent class analysis (LCA). The interest outcomes were overweight and obesity. Multinomial logistic regression models were used to study the relationship between victimization and overweight or obesity, controlling for confounders. LCA grouped boys and girls adolescents into three classes. These classes received the same labels, but the patterns differed between sexes. Class 1 was characterized by fewer types of victimization suffered and lower endorsement values in the analyzed items and was named bullying and indirect victimization (♀: 42.7%, n = 546; ♂: 21.6%, n = 293). Class 2 included more victimization types than Class 1 and less than Class 3. This class was labeled family violence and peer victimization (♀: 29.1%, n = 356; ♂: 47.9%, n = 652). Class 3 was named high polyvictimization (♀: 28.2%, n = 345; ♂: 30.5%, n = 418). According to Finkelhor, polyvictimization was not associated with overweight or obesity in both sexes. Only the class of high polyvictimization was associated with being overweight (ORadj: 1.60, 95%CI: 1.01-2.54) in girls. In this study, polyvictimization was associated with being overweight only among adolescent girls. Longitudinal studies in different contexts and populations are needed to understand this relationship.


Assuntos
Bullying , Vítimas de Crime , Masculino , Feminino , Criança , Humanos , Adolescente , Sobrepeso/epidemiologia , Brasil/epidemiologia , Obesidade
8.
BMC Musculoskelet Disord ; 24(1): 431, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37254174

RESUMO

BACKGROUND: Quadriceps tendon rupture (QTR) is a severe injury of the knee extensor apparatus. The study aims to validate the use of forgotten joint score (FJS-12) for functional outcome assessing after surgical treatment of QTR. METHODS: Fifty-seven patients who underwent surgery for QTR with transosseous suture reconstruction in a single orthopaedic surgery and traumatology center between 2015 and 2020 were eligible for enrolment in this retrospective case series. The demographic data and other pre-operative details such as age, gender, comorbidities and medication use also were extracted from the medical records. Patient reported outcome measures (PROMs) were gathered in the form of Western Ontario and McMaster Universities Arthritis Index Score (WOMAC), Tegner Activity Score (TAS), Lysholm Score and FJS-12 at a mean follow-up time of 49.84 months ± 20.64 months. The FJS-12 was validated by correlation with WOMAC, TAS and Lysholm Score. RESULTS: The mean age of all patients were 69.2 ± 13.6 years with 51 (89.5%) males and 6 (10.5%) females. The mean time from injury to surgery was 3.39 ± 5.46 days. All patients reported satisfactory functional outcomes after surgery on FJS-12, WOMAC and Lysholm scores, except the TAS, which decreased slightly from pre-operative level. There was a high negative correlation between WOMAC and FJS-12, but moderate positive correlations between FJS-12 and TAS and Lysholm scores. The Cronbach's alpha value was 0.96 for 12 items in FJS-12. CONCLUSION: This study has found that FJS-12 is a reliable and easy to assess tool for functional outcomes after QTR reconstruction. It has shown moderate to strong correlation with other commonly used outcome measures (WOMAC, TAS and Lysholm).


Assuntos
Artroplastia do Joelho , Traumatismos dos Tendões , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Estudos Retrospectivos , Articulação do Joelho/cirurgia , Avaliação de Resultados em Cuidados de Saúde , Tendões/cirurgia , Traumatismos dos Tendões/diagnóstico , Traumatismos dos Tendões/cirurgia
9.
J Res Adolesc ; 33(4): 1268-1280, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37395433

RESUMO

Emotion dysregulation is increasingly implicated as a transdiagnostic risk factor in the etiology of mental health problems. This project aimed to explore the links between emotion regulation, negative parenting and student-teacher relationships using longitudinal and ecologically valid data. A sample of n = 209 young people enrolled in the 'Decades-to-Minutes' (D2M) study, based in Zurich, Switzerland, provided data from the ages of 7-20 via parent- and self-report questionnaires and ecological momentary assessment. Data were analyzed using Dynamic Structural Equation Modeling (DSEM). Worse student-teacher relationships predicted increased negative affectivity and emotional lability. Negative parenting practices predicted emotional lability only via their impact on student-teacher relationships. The findings point to worse student-teacher relationships as risk factors in the socioemotional development of children and young people.


Assuntos
Avaliação Momentânea Ecológica , Poder Familiar , Criança , Humanos , Adolescente , Poder Familiar/psicologia , Emoções/fisiologia , Estudantes/psicologia , Pais/psicologia
10.
Aggress Behav ; 49(5): 469-479, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36891623

RESUMO

The relation between attention deficit hyperactivity disorder (ADHD) symptoms and aggression is well documented; however, the processes that account for higher levels of aggression associated with ADHD in the course of daily life are little understood. The current study used ecological momentary assessment to explore how ADHD traits relate to individual differences in perceiving provocation from others and the resultant aggressive behaviors; and the strengths of the links between provocation and aggression in the flow of daily life. A dynamic structural equation model was fit using data from a subpopulation of young adults involved in the longitudinal z-proso study (n = 259, median-age 20). Data on provocation and aggression was collected at four quasi-random time periods per day over a 14-day period. Individuals with higher ADHD trait levels reported higher instances of provocation and aggression, with ADHD traits significantly moderating aggression inertia such that those with higher levels of ADHD traits showed greater persistence of aggressive behavior over time. However, ADHD trait levels did not significantly moderate any of the observed cross-lagged effects. Our findings suggest that individuals with higher levels of ADHD traits are at greater risk of exposure to interpersonal interactions involving interpersonal provocation, show higher levels of aggressive behavior in daily life, and find it more difficult to reduce their aggression once triggered. These findings support the importance of targeting factors such as social skills and emotion regulation that may underpin the increased difficulties in interpersonal interactions often experienced by individuals with high levels of ADHD symptoms.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Adulto Jovem , Humanos , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Análise de Classes Latentes , Agressão/psicologia , Estudos Longitudinais , Relações Interpessoais
11.
Knee Surg Sports Traumatol Arthrosc ; 31(5): 1840-1850, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36811657

RESUMO

PURPOSE: The purpose of this study was to visualise the influence of alignment strategy on bone resection in varus knee phenotypes. The hypothesis was that different amounts of bone resection would be required depending on the alignment strategy chosen. Through visualisation of the corresponding bone sections, it was hypothesised, it would be possible to assess which of the different alignment strategies would require the least amount of change to the soft tissues for the chosen phenotype, whilst still ensuring acceptable alignment of the components, and thus could be considered the most ideal alignment strategy. METHODS: Simulations of the different alignment strategies (mechanical, anatomical, constrained kinematic and unconstrained kinematic) in relation to their bone resections were performed on five common exemplary varus knee phenotypes. VARHKA174° VARFMA87° VARTMA84°, VARHKA174° VARFMA90° NEUTMA87°, VARHKA174° NEUFMA93° VARTMA84°, VARHKA177° NEUFMA93° NEUTMA87° and VARHKA177° VALFMA96° VARTMA81°. The phenotype system used categorises knees based on overall limb alignment (i.e. hip knee angle) but also takes into account joint line obliquity (i.e. TKA and FMA) and has been applied in the global orthopaedic community since its introduction in 2019. The simulations are based on long-leg radiographs under load. It is assumed that a change of 1° in the alignment of the joint line corresponds to a displacement of the distal condyle by 1 mm. RESULTS: In the most common phenotype VARHKA174° NEUFMA93° VARTMA84°, a mechanical alignment would result in an asymmetric elevation of the tibial medial joint line by 6 mm and a lateral distalisation of the femoral condyle by 3 mm, an anatomical alignment only by 0 and 3 mm, a restricted by 3 and 3 mm, respectively, whilst a kinematic alignment would result in no change in joint line obliquity. In the similarly common phenotype 2 VARHKA174° VARFMA90° NEUTMA87° with the same HKA, the changes are considerably less with only 3 mm asymmetric height change on one joint side, respectively, and no change in restricted or kinematic alignment. CONCLUSION: This study shows that significantly different amounts of bone resection are required depending on the varus phenotype and the alignment strategy chosen. Based on the simulations performed, it can, therefore, be assumed that an individual decision for the respective phenotype is more important than the dogmatically correct alignment strategy. By including such simulations, the modern orthopaedic surgeon can now avoid biomechanically inferior alignments and still obtain the most natural possible knee alignment for the patient.


Assuntos
Artroplastia do Joelho , Fraturas Ósseas , Humanos , Estudos Retrospectivos , Articulação do Joelho/cirurgia , Tíbia/cirurgia , Fenótipo , Fraturas Ósseas/cirurgia
12.
Sensors (Basel) ; 23(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36679598

RESUMO

Vital signs estimation provides valuable information about an individual's overall health status. Gathering such information usually requires wearable devices or privacy-invasive settings. In this work, we propose a radar-based user-adaptable solution for respiratory signal prediction while sitting at an office desk. Such an approach leads to a contact-free, privacy-friendly, and easily adaptable system with little reference training data. Data from 24 subjects are preprocessed to extract respiration information using a 60 GHz frequency-modulated continuous wave radar. With few training examples, episodic optimization-based learning allows for generalization to new individuals. Episodically, a convolutional variational autoencoder learns how to map the processed radar data to a reference signal, generating a constrained latent space to the central respiration frequency. Moreover, autocorrelation over recorded radar data time assesses the information corruption due to subject motions. The model learning procedure and breathing prediction are adjusted by exploiting the motion corruption level. Thanks to the episodic acquired knowledge, the model requires an adaptation time of less than one and two seconds for one to five training examples, respectively. The suggested approach represents a novel, quickly adaptable, non-contact alternative for office settings with little user motion.


Assuntos
Radar , Processamento de Sinais Assistido por Computador , Humanos , Monitorização Fisiológica/métodos , Sinais Vitais , Taxa Respiratória , Respiração , Algoritmos , Frequência Cardíaca
13.
Arch Womens Ment Health ; 25(3): 633-640, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35420323

RESUMO

Maternal prenatal stress places a substantial burden on mother's mental health. Expectant mothers in low- and middle-income countries (LMICs) have thus far received less attention than mothers in high-income settings. This is particularly problematic, as a range of triggers, such as exposure to traumatic events (e.g. natural disasters, previous pregnancy losses) and adverse life circumstances (e.g. poverty, community violence), put mothers at increased risk of experiencing prenatal stress. The ten-item Perceived Stress Scale (PSS-10) is a widely recognised index of subjective experience of stress that is increasingly used in LMICs. However, evidence for its measurement equivalence across settings is lacking. This study aims to assess measurement invariance of the PSS-10 across eight LMICs and across birth parity. This research was carried out as part of the Evidence for Better Lives Study (EBLS, vrc.crim.cam.ac.uk/vrcresearch/EBLS). The PSS-10 was administered to N = 1,208 expectant mothers from Ghana, Jamaica, Pakistan, the Philippines, Romania, South Africa, Sri Lanka and Vietnam during the third trimester of pregnancy. Confirmatory factor analysis suggested a good model fit of a two-factor model across all sites, with items on experiences of stress loading onto a negative factor and items on perceived coping onto a positive factor. Configural and metric, but not full or partial scalar invariance, were established across all sites. Configural, metric and full scalar invariance could be established across birth parity. On average, first-time mothers reported less stress than mothers who already had children. Our findings indicate that the PSS-10 holds utility in assessing stress across a broad range of culturally diverse settings; however, caution should be taken when comparing mean stress levels across sites.


Assuntos
Mães , Parto , Criança , Análise Fatorial , Feminino , Humanos , Paridade , Gravidez , Psicometria , Estresse Psicológico/diagnóstico
14.
Hautarzt ; 73(6): 485-487, 2022 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-34609536

RESUMO

We report a case of a 57-year-old slightly obese woman with localized itch on the arms accompanied by stinging and burning sensations. A few excoriations were observed upon clinical examination. The MRI examination of the cervical spine revealed a meningioma at C5/C6 level. The diagnosis of brachioradial pruritus due to compression of the cervical myelon was further supported by a positive ice-pack sign. Disc herniation or prolapse, foraminal stenosis and degenerative alterations constitute other possible causes of brachioradial pruritus.


Assuntos
Neoplasias Meníngeas , Meningioma , Vértebras Cervicais/diagnóstico por imagem , Feminino , Humanos , Neoplasias Meníngeas/complicações , Neoplasias Meníngeas/diagnóstico , Meningioma/complicações , Meningioma/diagnóstico , Pessoa de Meia-Idade , Pescoço , Prurido/diagnóstico , Prurido/etiologia
15.
Nat Mater ; 19(5): 576, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31719690

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

16.
Nat Mater ; 19(4): 386-390, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31685944

RESUMO

Chirality, a foundational concept throughout science, may arise at ferromagnetic domain walls1 and in related objects such as skyrmions2. However, chiral textures should also exist in other types of ferroic materials, such as antiferromagnets, for which theory predicts that they should move faster for lower power3, and ferroelectrics, where they should be extremely small and possess unusual topologies4,5. Here, we report the concomitant observation of antiferromagnetic and electric chiral textures at domain walls in the room-temperature ferroelectric antiferromagnet BiFeO3. Combining reciprocal and real-space characterization techniques, we reveal the presence of periodic chiral antiferromagnetic objects along the domain walls as well as a priori energetically unfavourable chiral ferroelectric domain walls. We discuss the mechanisms underlying their formation and their relevance for electrically controlled topological oxide electronics and spintronics.

17.
Glob Chang Biol ; 27(11): 2458-2477, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33538378

RESUMO

Increasing soil organic carbon (SOC) stocks is a promising way to mitigate the increase in atmospheric CO2 concentration. Based on a simple ratio between CO2 anthropogenic emissions and SOC stocks worldwide, it has been suggested that a 0.4% (4 per 1000) yearly increase in SOC stocks could compensate for current anthropogenic CO2 emissions. Here, we used a reverse RothC modelling approach to estimate the amount of C inputs to soils required to sustain current SOC stocks and to increase them by 4‰ per year over a period of 30 years. We assessed the feasibility of this aspirational target first by comparing the required C input with net primary productivity (NPP) flowing to the soil, and second by considering the SOC saturation concept. Calculations were performed for mainland France, at a 1 km grid cell resolution. Results showed that a 30%-40% increase in C inputs to soil would be needed to obtain a 4‰ increase per year over a 30-year period. 88.4% of cropland areas were considered unsaturated in terms of mineral-associated SOC, but characterized by a below target C balance, that is, less NPP available than required to reach the 4‰ aspirational target. Conversely, 90.4% of unimproved grasslands were characterized by an above target C balance, that is, enough NPP to reach the 4‰ objective, but 59.1% were also saturated. The situation of improved grasslands and forests was more evenly distributed among the four categories (saturated vs. unsaturated and above vs below target C balance). Future data from soil monitoring networks should enable to validate these results. Overall, our results suggest that, for mainland France, priorities should be (1) to increase NPP returns in cropland soils that are unsaturated and have a below target carbon balance and (2) to preserve SOC stocks in other land uses.


Assuntos
Carbono , Solo , Carbono/análise , Sequestro de Carbono , Estudos de Viabilidade , França
18.
Eur J Clin Invest ; 51(11): e13606, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34076253

RESUMO

BACKGROUND: Heart failure is one of the most pressing current public health concerns. However, in Spain there is a lack of population data. We aimed to examine thirteen-year nationwide trends in heart failure hospitalization, in-hospital mortality and 30-day readmission rates in Spain. METHODS: We conducted a retrospective observational study of patients discharged with the principal diagnosis of heart failure from The National Health System' acute hospitals during 2003-2015. The source of the data was the Minimum Basic Data Set. Temporal trends were modelled using Poisson regression analysis. The risk-standardized in-hospital mortality ratio was calculated using a multilevel risk adjustment logistic regression model. RESULTS: A total of 1 254 830 episodes of heart failure were selected. Throughout 2003-2015, the number of hospital discharges with principal diagnosis of heart failure increased by 61%. Discharge rates weighted by age and sex increased during the period [incidence rate ratio (IRR): 1.03; 95% confidence interval (95% CI): 1.03-1.03; P < .001)], although this increase was motivated by the increase in older age groups (≥75 years old). The crude mortality rate diminished (IRR: 0.99; 95% CI: 0.98-1, P < .001), but 30-day readmission rate increased (IRR: 1.05; 95% CI: 1.04-1.06; P < .001). The risk-standardized in-hospital mortality ratio did not change throughout the study period (IRR: 0.997; 95% CI: 0.992-1; P = .32). CONCLUSIONS: From 2003 to 2015, heart failure admission rates increased significantly in Spain as a consequence of the sustained increase of hospitalization in the population ≥75 years. 30-day readmission rates increased, but the risk-standardized in-hospital mortality ratio did not significantly change for the same period.


Assuntos
Insuficiência Cardíaca/epidemiologia , Mortalidade Hospitalar/tendências , Hospitalização/tendências , Readmissão do Paciente/tendências , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais , Espanha/epidemiologia
19.
Opt Lett ; 46(14): 3452-3455, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34264236

RESUMO

This Letter introduces a technique for performing binary adaptive optics, which is carried out by optical components only, without the help of any electronic or optoelectronic device. In this technique, the interferogram produced by a point diffraction interferometer modulates a light-driven crystal. The modulated light-driven crystal may produce pupil-plane only-phase or only-amplitude binary masks to mitigate phase aberrations. The capability of working unsupported makes it suitable for application in hard-to-reach or hazardous locations such as satellites, underwater, or contaminated places. The Letter includes an experimental validation where the ability of the technique to produce pupil amplitude masking is confirmed.

20.
J Child Psychol Psychiatry ; 62(2): 232-243, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32474921

RESUMO

BACKGROUND: Irritability is frequently comorbid with ADHD. Although irritability alone has been linked to deleterious mental health and adaptive issues, the joint developmental course of ADHD and irritability symptoms during childhood as well as its association with later mental health and suicidal outcomes is not fully understood. We aimed to describe the developmental trajectories of childhood ADHD and irritability symptoms and to quantify their association with adolescent mental health and suicidal outcomes. METHODS: The Quebec Longitudinal Study of Child Development (QLSCD) included 1407 participants from the general population followed up from age 5 months to 17 years. We used a multitrajectory approach to identify developmental trajectories of childhood (6-12 years) ADHD and irritability symptoms. Outcome measures were adolescent (13-17 years) mental health (psychiatric symptoms/functional impairment) and suicidal outcomes. RESULTS: We identified distinct developmental profiles: combined absent or very low ADHD and absent or very low irritability (940 [66.8%]; reference group), moderately high irritability and low ADHD (158 [11.2%]), moderately high ADHD and low irritability (198 [14.1%]), and combined high ADHD and high irritability (111 [7.9%]). Multivariate modeling showed that, compared to children in the reference group, those in the combined high ADHD and high irritability profile showed higher levels of ADHD continuity (d ranges = 0.40-0.50), externalizing (d ranges = 0.25-0.59), internalizing (d ranges = 0.20-0.29), and functional impairments (d ranges = 0.17-0.48) and suicidal behaviors (odds ratio (OR) = 2.12, confidence interval (CI) = 1.47-3.06) in adolescence. CONCLUSIONS: The presence of persistently high levels of irritability along with ADHD symptoms during childhood significantly predicts adolescent ADHD continuity, externalizing, internalizing, and suicidal outcomes. Systematic consideration of irritability when assessing and treating ADHD may improve long-term mental health outcomes.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Criança , Humanos , Recém-Nascido , Humor Irritável , Estudos Longitudinais , Saúde Mental , Ideação Suicida
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