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1.
Nat Mater ; 23(4): 519-526, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38480865

RESUMO

Hyperfluorescence shows great promise for the next generation of commercially feasible blue organic light-emitting diodes, for which eliminating the Dexter transfer to terminal emitter triplet states is key to efficiency and stability. Current devices rely on high-gap matrices to prevent Dexter transfer, which unfortunately leads to overly complex devices from a fabrication standpoint. Here we introduce a molecular design where ultranarrowband blue emitters are covalently encapsulated by insulating alkylene straps. Organic light-emitting diodes with simple emissive layers consisting of pristine thermally activated delayed fluorescence hosts doped with encapsulated terminal emitters exhibit negligible external quantum efficiency drops compared with non-doped devices, enabling a maximum external quantum efficiency of 21.5%. To explain the high efficiency in the absence of high-gap matrices, we turn to transient absorption spectroscopy. It is directly observed that Dexter transfer from a pristine thermally activated delayed fluorescence sensitizer host can be substantially reduced by an encapsulated terminal emitter, opening the door to highly efficient 'matrix-free' blue hyperfluorescence.

2.
J Antimicrob Chemother ; 79(5): 1019-1022, 2024 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-38471817

RESUMO

OBJECTIVES: To calculate a risk-adjusted mortality ratio (RAMR) for bloodstream infections (BSIs) using all-patient refined diagnosis-related groups (APR-DRGs) and compare it with the crude mortality rate (CMR). METHODS: Retrospective observational study of prevalent BSI at our institution from January 2019 to December 2022. In-hospital mortality was adjusted with a binary logistic regression model adjusting for sex, age, admission type and mortality risk for the hospitalization episode according to the four severity levels of APR DRGs. The RAMR was calculated as the ratio of observed to expected in-hospital mortality, and the CMR was calculated as the proportion of deaths among all bacteraemia episodes. RESULTS: Of 2939 BSIs, 2541 were included: Escherichia coli (n = 1310), Klebsiella pneumoniae (n = 428), Pseudomonas aeruginosa (n = 209), Staphylococcus aureus (n = 498) and candidaemia (n = 96). A total of 436 (17.2%) patients died during hospitalization and 279 died within the first 14 days after the onset of BSI. Throughout the period, all BSI cases had a mortality rate above the expected adjusted mortality (RAMR value greater than 1), except for Escherichia coli (1.03; 95% CI 0.86-1.21). The highest overall RAMR values were observed for P. aeruginosa, Candida and S. aureus with 2.06 (95% CI 1.57-2.62), 1.99 (95% CI 1.3-2.81) and 1.8 (95% CI 1.47-2.16), respectively. The temporal evolution of CMR may differ from RAMR, especially in E. coli, where it was reversed. CONCLUSIONS: RAMR showed higher than expected mortality for all BSIs studied except E. coli and provides complementary to and more clinically comprehensive information than CMR, the currently recommended antibiotic stewardship programme mortality indicator.


Assuntos
Bacteriemia , Mortalidade Hospitalar , Humanos , Estudos Retrospectivos , Masculino , Feminino , Idoso , Bacteriemia/mortalidade , Bacteriemia/microbiologia , Bacteriemia/diagnóstico , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Hospitalização/estatística & dados numéricos , Escherichia coli/isolamento & purificação , Adulto
3.
Electrophoresis ; 45(1-2): 69-100, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37259641

RESUMO

Proteins are important molecules involved in an immensely large number of biological processes. Being capable of manipulating proteins is critical for developing reliable and affordable techniques to analyze and/or detect them. Such techniques would enable the production of therapeutic agents for the treatment of diseases or other biotechnological applications (e.g., bioreactors or biocatalysis). Microfluidic technology represents a potential solution to protein manipulation challenges because of the diverse phenomena that can be exploited to achieve micro- and nanoparticle manipulation. In this review, we discuss recent contributions made in the field of protein manipulation in microfluidic systems using different physicochemical principles and techniques, some of which are miniaturized versions of already established macro-scale techniques.


Assuntos
Técnicas Analíticas Microfluídicas , Nanopartículas , Microfluídica/métodos , Técnicas Analíticas Microfluídicas/métodos , Nanopartículas/química , Dispositivos Lab-On-A-Chip
4.
Cytotherapy ; 26(10): 1193-1200, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38775773

RESUMO

BACKGROUND: Hematopoietic cell transplantation (HCT) is a promising treatment for hematological diseases, yet access barriers like cost and limited transplant centers persist. Telemedicine-based patient navigation (PN) has emerged as a solution. This study presents a cost-free PN telemedicine clinic (TC) in collaboration with the National Marrow Donor Program. AIM: to assess its feasibility and impac on HCT access determined by the cumulative incidence of transplantation. METHODS: In this single-center cohort study, patients of all ages and diagnoses referred for HCT participated. Two transplant physician-navigators established patient relationships via video calls, collecting medical history, offering HCT education and recommending pretransplant tests. The analysis involved descriptive statistics and intent-to-transplant survival assessment. RESULTS: One hundred and three patients were included of whom n = 78 were referred for allogeneic HCT (alloHCT), with a median age of 28 years. The median time from initial contact to the first consult was 5 days. The cumulative incidence of transplantation was 50% at 6 months and 61% at 12 months, with varying outcomes based on HCT type. Notably, 49 patients were not transplanted, primarily due to refractory disease, progression or relapse (57.1%). Autologous HCT candidates and physician referrals were correlated with higher transplant success compared to alloHCT candidates and patients who were not referred by a physician. CONCLUSION: Our pretransplant TC was feasible, facilitating access to HCT. Disease relapse posed a significant barrier. Enhancing timely physician referrals should be a focus for future efforts.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Navegação de Pacientes , Telemedicina , Humanos , Transplante de Células-Tronco Hematopoéticas/métodos , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Adolescente , Criança , Adulto Jovem , Pré-Escolar , Acessibilidade aos Serviços de Saúde , Idoso , Estudos de Coortes , Lactente , Transplante Homólogo/métodos
5.
J Anim Ecol ; 93(1): 95-108, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38078562

RESUMO

In most bird species, parents raise offspring cooperatively. In some cases, this cooperation extends to helpers-at-the-nest who assist the breeders with a range of tasks. While cooperative food provisioning might merely arise incidentally, as a result of the efforts of carers that act independently from each other, recent studies suggest that birds may coordinate by taking turns in visiting the nest. However, evidence that such coordination emerges because individuals actively respond to each other's behaviour is controversial, and the potential benefits of carers' alternation remain unknown. We addressed this knowledge gap by analysing a multiyear dataset for cooperatively breeding carrion crows Corvus corone, comprising 8693 nest visits across 50 groups. Our results reveal that turn-taking does occur in this species and that all group members, regardless of their sex and social role (breeder/helper), tend to alternate at the nest with other carers rather than to make repeat visits. Importantly, we found that the body mass of nestlings increased significantly with the degree of carers' alternation, possibly because well-coordinated groups provided food at more regular intervals. Using earlier monitoring data, the observed increase in body mass is predicted to substantially boost postfledging survival rates. Our analyses demonstrate that alternation in nestling provisioning has measurable fitness benefits in this study system. This raises the possibility that cooperatively breeding carrion crows, as well as other bird species with similarly coordinated brood provisioning, exhibit specialized behavioural strategies that enable effective alternation.


En la mayoría de las especies de aves, los padres cooperan entre sí en el cuidado de sus crías. En algunos casos, la cooperación se extiende a individuos ayudantes que asisten a los reproductores en diferentes tareas. El aprovisionamiento cooperativo de las crías puede darse simplemente como resultado del esfuerzo de cuidadores que actúan de forma independiente, pero estudios recientes sugieren que las aves pueden coordinarse, tomando turnos a la hora de visitar el nido. Sin embargo, las evidencias de que dicha coordinación ocurre porque los individuos realmente responden al comportamiento de los demás es controvertida, y los potenciales beneficios de la alternancia al nido son desconocidos. Nosotros abordamos estos aspectos analizando una base de datos plurianual en la corneja negra Corvus corone, que incluye 8693 visitas al nido en 50 grupos. Nuestros resultados revelan que se produce toma de turnos en esta especie y que todos los miembros del grupo, independientemente del sexo y del estatus social (reproductor / ayudante), tienden a alternarse al nido con otros cuidadores, en vez de repetir visitas. Más importante aún, encontramos que la masa corporal de los polluelos aumentaba de forma significativa al aumentar el grado de coordinación de los cuidadores, posiblemente porque los grupos mejor coordinados aprovisionaban las crías a intervalos más regulares. Basándonos en datos anteriores, pudimos calcular que el incremento observado en masa corporal predice un aumento sustancial de la tasa de supervivencia de los volanderos. Nuestros análisis demuestran, por lo tanto, que la alternancia al nido tiene beneficios medibles en eficacia biológica. Esto conlleva la posibilidad de que las cornejas negras cooperativas, al igual que otras especies de aves con aprovisionamiento coordinado de las crías, exhiban estrategias comportamentales especializadas que permitan una eficiente alternancia al nido.


Assuntos
Corvos , Aves Canoras , Humanos , Animais , Comportamento Cooperativo , Cruzamento , Comportamento de Nidação
6.
Analyst ; 149(8): 2469-2479, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38516870

RESUMO

There is a growing interest in the advancement of microscale electrokinetic (EK) systems for biomedical and clinical applications, as these systems offer attractive characteristics such as portability, robustness, low sample requirements and short response time. The present work is focused on manipulating the characteristics of the insulating post arrangement in insulator-based EK (iEK) systems for separating a binary mixture of spherical microparticles with same diameter (5.1 µm), same shape, made from the same substrate material and only differing in their zeta potential by ∼14 mV. This study presents a combination of mathematical modeling and experimental separations performed by applying a low-frequency alternating current (AC) voltage in iEK systems with 12 distinct post arrangements. These iEK devices were used to systematically study the effect of three spatial characteristics of the insulating post array on particle separations: the horizontal separation and the vertical separation between posts, and introducing an offset to the posts arrangement. Through normalization of the spatial separation between the insulating posts with respect to particle diameter, guidelines to improve separation resolution for different particle mixtures possessing similar characteristics were successfully identified. The results indicated that by carefully designing the spatial arrangement of the post array, separation resolution values in the range of 1.4-2.8 can be obtained, illustrating the importance and effect of the arrangement of insulating posts on improving particle separations. This study demonstrates that iEK devices, with effectively designed spatial arrangement of the insulating post arrays, have the capabilities to perform discriminatory separations of microparticles of similar characteristics.

7.
Analyst ; 149(14): 3839-3849, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38855835

RESUMO

Insulator-based electrokinetically driven microfluidic devices stimulated with direct current (DC) voltages are an attractive solution for particle separation, concentration, or isolation. However, to design successful particle manipulation protocols, it is mandatory to know the mobilities of electroosmosis, and linear and nonlinear electrophoresis of the microchannel/liquid/particle system. Several techniques exist to characterize the mobilities of electroosmosis and linear electrophoresis. However, only one method to characterize the mobility of nonlinear electrophoresis has been thoroughly assessed, which generally requires DC voltages larger than 1000 V and measuring particle velocity in a straight microchannel. Under such conditions, Joule heating, electrolysis, and the DC power source cost become a concern. Also, measuring particle velocity at high voltages is noisy, limiting characterization quality. Here we present a protocol-tested on 2 µm polystyrene particles-for characterizing the mobility of nonlinear electrophoresis of the liquid/particle system using a DC voltage of only 30 V and visual inspection of particle dynamics in a microchannel featuring insulating obstacles. Multiphysics numerical modelling was used to guide microchannel design and to correlate particle location during an experiment with electric field intensity. The method was validated against the conventional characterization protocol, exhibiting excellent agreement while significantly reducing measurement noise and experimental complexity.

8.
Eur Arch Psychiatry Clin Neurosci ; 274(4): 837-847, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38243018

RESUMO

Schizophrenia has been associated with a reduced task-related modulation of cortical activity assessed through electroencephalography (EEG). However, to the best of our knowledge, no study so far has assessed the underpinnings of this decreased EEG modulation in schizophrenia. A possible substrate of these findings could be a decreased inhibitory function, a replicated finding in the field. In this pilot study, our aim was to explore the association between EEG modulation during a cognitive task and the inhibitory system function in vivo in a sample including healthy controls and patients with schizophrenia. We hypothesized that the replicated decreased task-related activity modulation during a cognitive task in schizophrenia would be related to a hypofunction of the inhibitory system. For this purpose, 27 healthy controls and 22 patients with schizophrenia (including 13 first episodes) performed a 3-condition auditory oddball task from which the spectral entropy modulation was calculated. In addition, cortical reactivity-as an index of the inhibitory function-was assessed by the administration of 75 monophasic transcranial magnetic stimulation single pulses over the left dorsolateral prefrontal cortex. Our results replicated the task-related cortical activity modulation deficit in schizophrenia patients. Moreover, schizophrenia patients showed higher cortical reactivity following transcranial magnetic stimulation single pulses over the left dorsolateral prefrontal cortex compared to healthy controls. Cortical reactivity was inversely associated with EEG modulation, supporting the idea that a hypofunction of the inhibitory system could hamper the task-related modulation of EEG activity.


Assuntos
Eletroencefalografia , Esquizofrenia , Estimulação Magnética Transcraniana , Humanos , Esquizofrenia/fisiopatologia , Masculino , Feminino , Adulto , Projetos Piloto , Adulto Jovem , Inibição Psicológica , Pessoa de Meia-Idade , Córtex Pré-Frontal Dorsolateral/fisiopatologia , Córtex Pré-Frontal Dorsolateral/fisiologia , Inibição Neural/fisiologia , Córtex Cerebral/fisiopatologia
9.
Retina ; 44(3): 487-497, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37972955

RESUMO

PURPOSE: The LIGHTSITE III study evaluated multiwavelength photobiomodulation (PBM) therapy in nonexudative (dry) age-related macular degeneration (AMD) using the LumiThera Valeda Light Delivery System. METHODS: LIGHTSITE III is a randomized, controlled trial to assess the safety and effectiveness of PBM in dry AMD. Subjects were given multiwavelength PBM (590, 660, and 850 nm) or Sham treatment delivered in a series of nine sessions over 3 to 5 weeks every four months over 24 months. Subjects were assessed for efficacy and safety outcomes. Data from the 13-month analysis are presented in this report. RESULTS: A total of 100 subjects (148 eyes) with dry AMD were randomized. LIGHTSITE III met the primary efficacy best-corrected visual acuity endpoint with a significant difference between PBM (n = 91 eyes) and Sham (n = 54 eyes) groups (Between group difference: 2.4 letters (SE 1.15), CI: -4.7 to -0.1, P = 0.02) (PBM alone: 5.4 letters (SE 0.96), CI: 3.5 to 7.3, P < 0.0001; Sham alone: 3.0 letters (SE 1.13), CI: 0.7-5.2, P < 0.0001). The PBM group showed a significant decrease in new onset geographic atrophy ( P = 0.024, Fisher exact test, odds ratio 9.4). A favorable safety profile was observed. CONCLUSION: LIGHTSITE III provides a prospective, randomized, controlled trial showing improved clinical and anatomical outcomes in intermediate dry AMD following PBM therapy.


Assuntos
Atrofia Geográfica , Terapia com Luz de Baixa Intensidade , Degeneração Macular , Humanos , Estudos Prospectivos , Acuidade Visual , Degeneração Macular/diagnóstico , Degeneração Macular/radioterapia , Degeneração Macular/tratamento farmacológico , Olho , Atrofia Geográfica/diagnóstico , Atrofia Geográfica/radioterapia
10.
Sensors (Basel) ; 24(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38544121

RESUMO

The vast amount of information stemming from the deployment of the Internet of Things and open data portals is poised to provide significant benefits for both the private and public sectors, such as the development of value-added services or an increase in the efficiency of public services. This is further enhanced due to the potential of semantic information models such as NGSI-LD, which enable the enrichment and linkage of semantic data, strengthened by the contextual information present by definition. In this scenario, advanced data processing techniques need to be defined and developed for the processing of harmonised datasets and data streams. Our work is based on a structured approach that leverages the principles of linked-data modelling and semantics, as well as a data enrichment toolchain framework developed around NGSI-LD. Within this framework, we reveal the potential for enrichment and linkage techniques to reshape how data are exploited in smart cities, with a particular focus on citizen-centred initiatives. Moreover, we showcase the effectiveness of these data processing techniques through specific examples of entity transformations. The findings, which focus on improving data comprehension and bolstering smart city advancements, set the stage for the future exploration and refinement of the symbiosis between semantic data and smart city ecosystems.

11.
Sensors (Basel) ; 24(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38475231

RESUMO

Nowadays, there are plenty of data sources generating massive amounts of information that, combined with novel data analytics frameworks, are meant to support optimisation in many application domains. Nonetheless, there are still shortcomings in terms of data discoverability, accessibility and interoperability. Open Data portals have emerged as a shift towards openness and discoverability. However, they do not impose any condition to the data itself, just stipulate how datasets have to be described. Alternatively, the NGSI-LD standard pursues harmonisation in terms of data modelling and accessibility. This paper presents a solution that bridges these two domains (i.e., Open Data portals and NGSI-LD-based data) in order to keep benefiting from the structured description of datasets offered by Open Data portals, while ensuring the interoperability provided by the NGSI-LD standard. Our solution aggregates the data into coherent datasets and generate high-quality descriptions, ensuring comprehensiveness, interoperability and accessibility. The proposed solution has been validated through a real-world implementation that exposes IoT data in NGSI-LD format through the European Data Portal (EDP). Moreover, the results from the Metadata Quality Assessment that the EDP implements, show that the datasets' descriptions generated achieve excellent ranking in terms of the Findability, Accessibility, Interoperability and Reusability (FAIR) data principles.

12.
Sensors (Basel) ; 24(12)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38931591

RESUMO

In recent years, there has been a growing interest in developing portable and personal devices for measuring air quality and surrounding pollutants, partly due to the need for ventilation in the aftermath of COVID-19 situation. Moreover, the monitoring of hazardous chemical agents is a focus for ensuring compliance with safety standards and is an indispensable component in safeguarding human welfare. Air quality measurement is conducted by public institutions with high precision but costly equipment, which requires constant calibration and maintenance by highly qualified personnel for its proper operation. Such devices, used as reference stations, have a low spatial resolution since, due to their high cost, they are usually located in a few fixed places in the city or region to be studied. However, they also have a low temporal resolution, providing few samples per hour. To overcome these drawbacks and to provide people with personalized and up-to-date air quality information, a personal device (smartwatch) based on MEMS gas sensors has been developed. The methodology followed to validate the performance of the prototype was as follows: firstly, the detection capability was tested by measuring carbon dioxide and methane at different concentrations, resulting in low detection limits; secondly, several experiments were performed to test the discrimination capability against gases such as toluene, xylene, and ethylbenzene. principal component analysis of the data showed good separation and discrimination between the gases measured.


Assuntos
COVID-19 , Dióxido de Carbono , Monitoramento Ambiental , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Humanos , Dióxido de Carbono/análise , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Gases/análise , SARS-CoV-2/isolamento & purificação , Metano/análise
13.
J Stroke Cerebrovasc Dis ; 33(10): 107917, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39111374

RESUMO

OBJECTIVES: To describe the availability and barriers to access post-stroke rehabilitation services in Latin America. MATERIALS AND METHODS: We conducted a multi-national survey in Latin American countries. The survey consisted of three sections: (1) the national state of post-stroke rehabilitation; (2) the local state of post-stroke rehabilitation; and (3) the coverage and financing of post-stroke services. Stroke leaders from the surveyed countries were involved in developing and disseminating the survey. RESULTS: 261 responses were collected from 17 countries. The mean age of respondents was 42.4 ± 10.1 years, and 139 (54.5 %) of the respondents were male. National clinical guidelines for post-stroke rehabilitation were reported by 67 (25.7 %) of the respondents. However, there were discrepancies between respondents within the same country. Stroke units, physiotherapy, occupational therapy, speech therapy, and neuropsychological therapy services were less common in public than private settings. The main barriers for inpatient and outpatient services included limited rehabilitation facilities, coverage, and rehabilitation personnel. The main source of financing for the inpatient and outpatient services was the national health insurance, followed by out-of-pocket payments. Private and out-of-pocket costs were more frequently reported in outpatient services. CONCLUSIONS: Post-stroke rehabilitation services in Latin American countries are restricted due to a lack of coverage by the public health system and private insurers, human resources, and financial aid. Public settings offer fewer post-stroke rehabilitation services compared to private settings. Developing consensus guidelines, increasing coverage, and using innovative approaches to deliver post-stroke rehabilitation is paramount to increase access without posing a financial burden.


Assuntos
Pesquisas sobre Atenção à Saúde , Acessibilidade aos Serviços de Saúde , Reabilitação do Acidente Vascular Cerebral , Humanos , América Latina/epidemiologia , Reabilitação do Acidente Vascular Cerebral/economia , Acessibilidade aos Serviços de Saúde/economia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/economia , Acidente Vascular Cerebral/diagnóstico , Gastos em Saúde , Disparidades em Assistência à Saúde/economia , Guias de Prática Clínica como Assunto , Custos de Cuidados de Saúde , Centros de Reabilitação/economia , Assistência Ambulatorial/economia
14.
Int J Nurs Pract ; : e13313, 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39431424

RESUMO

INTRODUCTION: In-hospital falls represent significant health and economic concerns, but previous studies regarding the economic cost of falls do not account for other cofounders (comorbidities and clinical aspects) in this cost evaluation. AIM: The aim of this study is to analyse the cost of in-hospital falls comparing those who had falls to nonfalls patients while accounting for several risk factors associated with falls. METHODS: Data were collected from January 2020 to December 2022, in a private hospital in Brazil. The sample was divided into two groups: one with patients who fell and the other with nonfallers on a 1:2 ratio, and these groups were matched to avoid confounding variables. RESULTS: The median cost for patients who experienced falls was US$7520.26 compared to US$6144.24 for those without falls (p < 0.01). This trend was especially marked in men aged 20-40 who suffered falls and showed a significantly elevated median cost of US$29 722.02 distinguishing them from those without falls with a median cost of US$1179.48 (p < 0.01). CONCLUSION: Hospital falls significantly increase financial costs compared to nonfall cases, irrespective of comorbidities, length of stay or case-mix variations. The findings recommend a universal precautions approach to fall prevention in hospitals, targeting all hospitalised patients to effectively minimise the economic burden associated with in-hospital falls.

15.
Neuroimage ; 280: 120332, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37619796

RESUMO

The majority of electroencephalographic (EEG) and magnetoencephalographic (MEG) studies filter and analyse neural signals in specific frequency ranges, known as "canonical" frequency bands. However, this segmentation, is not exempt from limitations, mainly due to the lack of adaptation to the neural idiosyncrasies of each individual. In this study, we introduce a new data-driven method to automatically identify frequency ranges based on the topological similarity of the frequency-dependent functional neural network. The resting-state neural activity of 195 cognitively healthy subjects from three different databases (MEG: 123 subjects; EEG1: 27 subjects; EEG2: 45 subjects) was analysed. In a first step, MEG and EEG signals were filtered with a narrow-band filter bank (1 Hz bandwidth) from 1 to 70 Hz with a 0.5 Hz step. Next, the connectivity in each of these filtered signals was estimated using the orthogonalized version of the amplitude envelope correlation to obtain the frequency-dependent functional neural network. Finally, a community detection algorithm was used to identify communities in the frequency domain showing a similar network topology. We have called this approach the "Connectivity-based Meta-Bands" (CMB) algorithm. Additionally, two types of synthetic signals were used to configure the hyper-parameters of the CMB algorithm. We observed that the classical approaches to band segmentation are partially aligned with the underlying network topologies at group level for the MEG signals, but they are missing individual idiosyncrasies that may be biasing previous studies, as revealed by our methodology. On the other hand, the sensitivity of EEG signals to reflect this underlying frequency-dependent network structure is limited, revealing a simpler frequency parcellation, not aligned with that defined by the "canonical" frequency bands. To the best of our knowledge, this is the first study that proposes an unsupervised band segmentation method based on the topological similarity of functional neural network across frequencies. This methodology fully accounts for subject-specific patterns, providing more robust and personalized analyses, and paving the way for new studies focused on exploring the frequency-dependent structure of brain connectivity.


Assuntos
Eletroencefalografia , Magnetoencefalografia , Humanos , Algoritmos , Encéfalo , Bases de Dados Factuais
16.
J Am Chem Soc ; 145(42): 23205-23213, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37818771

RESUMO

An exceptional microsample from the ground layer of Leonardo da Vinci's Mona Lisa was analyzed by high-angular resolution synchrotron X-ray diffraction and micro Fourier transform infrared spectroscopy, revealing a singular mixture of strongly saponified oil with high lead content and a cerussite (PbCO3)-depleted lead white pigment. The most remarkable signature in the sample is the presence of plumbonacrite (Pb5(CO3)3O(OH)2), a rare compound that is stable only in an alkaline environment. Leonardo probably endeavored to prepare a thick paint suitable for covering the wooden panel of the Mona Lisa by treating the oil with a high load of lead II oxide, PbO. The review of Leonardo's manuscripts (original and latter translation) to track the mention of PbO gives ambiguous information. Conversely, the analysis of fragments from the Last Supper confirms that not only PbO was part of Leonardo's palette, through the detection of both litharge (α-PbO) and massicot (ß-PbO) but also plumbonacrite and shannonite (Pb2OCO3), the latter phase being detected for the first time in a historical painting.

17.
Anal Chem ; 95(26): 9914-9923, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37342914

RESUMO

There is an immediate need for the development of rapid and reliable methods for microparticle and cell assessments, and electrokinetic (EK) phenomena can be exploited to meet that need in a low cost and label-free fashion. The present study combines modeling and experimentation to separate a binary mixture of microparticles of the same size (5.1 µm), shape (spherical), and substrate material (polystyrene), but with a difference in particle zeta potentials of only ∼14 mV, by applying direct current (DC)-biased low-frequency alternating current (AC) voltages in an insulator-based-EK (iEK) system. Four distinct separations were carried out to systematically study the effect of fine-tuning each of the three main characteristics of the applied voltage: frequency, amplitude, and DC bias. The results indicate that fine-tuning each parameter improved the separation from an initial separation resolution Rs = 0.5 to a final resolution Rs = 3.1 of the fully fine-tuned separation. The separation method exhibited fair reproducibility in retention time with variations ranging from 6 to 26% between experimental repetitions. The present study demonstrates the potential to extend the limits of iEK systems coupled with carefully fine-tuned DC-biased low-frequency AC voltages to perform discriminatory micron-sized particle separations.

18.
Electrophoresis ; 44(1-2): 268-297, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36205631

RESUMO

Temperature is a critical-yet sometimes overlooked-parameter in microfluidics. Microfluidic devices can experience heating inside their channels during operation due to underlying physicochemical phenomena occurring therein. Such heating, whether required or not, must be monitored to ensure adequate device operation. Therefore, different techniques have been developed to measure and control temperature in microfluidic devices. In this contribution, the operating principles and applications of these techniques are reviewed. Temperature-monitoring instruments revised herein include thermocouples, thermistors, and custom-built temperature sensors. Of these, thermocouples exhibit the widest operating range; thermistors feature the highest accuracy; and custom-built temperature sensors demonstrate the best transduction. On the other hand, temperature control methods can be classified as external- or integrated-methods. Within the external methods, microheaters are shown to be the most adequate when working with biological samples, whereas Peltier elements are most useful in applications that require the development of temperature gradients. In contrast, integrated methods are based on chemical and physical properties, structural arrangements, which are characterized by their low fabrication cost and a wide range of applications. The potential integration of these platforms with the Internet of Things technology is discussed as a potential new trend in the field.


Assuntos
Técnicas Analíticas Microfluídicas , Temperatura , Microfluídica/métodos , Dispositivos Lab-On-A-Chip
19.
Gen Comp Endocrinol ; 343: 114369, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37611673

RESUMO

In starfish, a relaxin-like gonad-stimulating peptide (RGP) acts as a gonadotropin that triggers gamete maturation and spawning. In common with other relaxin/insulin superfamily peptides, RGP consists of an A- and a B-chain, with cross-linkages mediated by one intra- and two inter-chain disulfide bonds. In this study, a second relaxin-like peptide (RLP2) was identified in starfish species belonging to the orders Valvatida, Paxillosida, and Forcipulatida. Like RGP, RLP2 precursors comprise a signal peptide and a C-peptide in addition to the A- and B-chains. However, a unique cysteine motif [CC-(3X)-C-(10X)-C] is present in the A-chain of RLP2, which contrasts with the cysteine motif in other members of the relaxin/insulin superfamily [CC-(3X)-C-(8X)-C]. Importantly, in vitro pharmacological tests revealed that Patiria pectinifera RLP2 (Ppe-RLP2) and Asterias rubens RLP2 (Aru-RLP2) trigger shedding of mature eggs from ovaries of P. pectinifera and A. rubens, respectively. Furthermore, the potencies of Ppe-RLP2 and Aru-RLP2 as gonadotropic peptides were similar to those of Ppe-RGP and Aru-RGP, respectively, and the effect of RLP2 exhibited partial species-specificity. These findings indicate that two relaxin-type peptides regulate spawning in starfish and therefore we propose that RGP and RLP2 are renamed RGP1 and RGP2, respectively.


Assuntos
Asterias , Asterina , Relaxina , Animais , Estrelas-do-Mar , Cisteína , Peptídeo C , Insulina
20.
Retina ; 43(8): 1301-1307, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37130434

RESUMO

PURPOSE: Analysis of a 3-year, Phase 4, open-label, observational study evaluating the association of baseline best-corrected visual acuity (BCVA) with visual, treatment burden, and retinal thickness variability (RTV) outcomes and intraocular pressure (IOP)-related events after the 0.19-mg fluocinolone acetonide (FAc) intravitreal implant. METHODS: Data from patients with diabetic macular edema (DME) who did not have a clinically significant rise in IOP after previous corticosteroid treatment (N = 202 eyes from 159 patients) were segregated by baseline BCVA of ≥20/40 or <20/40 and analyzed for BCVA, number of yearly supplemental DME treatments, RTV, and incidence of IOP-related events. RESULTS: At 36 months post-FAc, eyes with better baseline BCVA (≥20/40) maintained baseline BCVA, whereas vision in eyes with worse baseline BCVA (<20/40) increased by approximately 7 letters to 61.34 letters (Snellen equivalent approximately 20/60; P < 0.05). Treatment burden and RTV decreased post-FAc regardless of baseline BCVA. Eyes with better baseline BCVA (≥20/40) had numerically fewer IOP-related events post-FAc versus eyes with worse baseline BCVA (<20/40), including a lower incidence of incisional IOP-lowering surgery. CONCLUSION: The 0.19-mg FAc implant improved RTV and treatment burden regardless of baseline BCVA. Better baseline BCVA (≥20/40) was associated with long-term BCVA maintenance. Although eyes with worse baseline BCVA (<20/40) experienced significantly improved BCVA, it never rose to the level of those with better baseline BCVA. These data indicate that early, effective intervention in DME, before significant vision loss occurs, is key to maintaining visual outcomes.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Edema Macular , Humanos , Glucocorticoides/uso terapêutico , Edema Macular/etiologia , Edema Macular/complicações , Retinopatia Diabética/complicações , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/tratamento farmacológico , Implantes de Medicamento , Fluocinolona Acetonida , Injeções Intravítreas
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