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1.
Nature ; 628(8009): 752-757, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38622268

RESUMO

In recent years, the stacking and twisting of atom-thin structures with matching crystal symmetry has provided a unique way to create new superlattice structures in which new properties emerge1,2. In parallel, control over the temporal characteristics of strong light fields has allowed researchers to manipulate coherent electron transport in such atom-thin structures on sublaser-cycle timescales3,4. Here we demonstrate a tailored light-wave-driven analogue to twisted layer stacking. Tailoring the spatial symmetry of the light waveform to that of the lattice of a hexagonal boron nitride monolayer and then twisting this waveform result in optical control of time-reversal symmetry breaking5 and the realization of the topological Haldane model6 in a laser-dressed two-dimensional insulating crystal. Further, the parameters of the effective Haldane-type Hamiltonian can be controlled by rotating the light waveform, thus enabling ultrafast switching between band structure configurations and allowing unprecedented control over the magnitude, location and curvature of the bandgap. This results in an asymmetric population between complementary quantum valleys that leads to a measurable valley Hall current7, which can be detected by optical harmonic polarimetry. The universality and robustness of our scheme paves the way to valley-selective bandgap engineering on the fly and unlocks the possibility of creating few-femtosecond switches with quantum degrees of freedom.


Assuntos
Compostos de Boro , Luz , Compostos de Boro/química , Lasers , Transporte de Elétrons , Teoria Quântica
2.
JMIR Res Protoc ; 13: e52365, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564249

RESUMO

BACKGROUND: Ankle-foot orthoses (AFOs) are vital in gait rehabilitation for patients with stroke. However, many conventional AFO designs may not offer the required precision for optimized patient outcomes. With the advent of 3D scanning and printing technology, there is potential for more individualized AFO solutions, aiming to enhance the rehabilitative process. OBJECTIVE: This nonrandomized trial seeks to introduce and validate a novel system for AFO design tailored to patients with stroke. By leveraging the capabilities of 3D scanning and bespoke software solutions, the aim is to produce orthoses that might surpass conventional designs in terms of biomechanical effectiveness and patient satisfaction. METHODS: A distinctive 3D scanner, complemented by specialized software, will be developed to accurately capture the biomechanical data of leg movements during gait in patients with stroke. The acquired data will subsequently guide the creation of patient-specific AFO designs. These personalized orthoses will be provided to participants, and their efficacy will be compared with traditional AFO models. The qualitative dimensions of this experience will be evaluated using the Quebec User Evaluation of Satisfaction With Assistive Technology (QUEST) assessment tool. Feedback from health care professionals and the participants will be considered throughout the trial to ensure a rounded understanding of the system's implications. RESULTS: Spatial-temporal parameters will be statistically compared using paired t tests to determine significant differences between walking with the personalized orthosis, the existing orthosis, and barefoot conditions. Significant differences will be identified based on P values, with P<.05 indicating statistical significance. The Statistical Parametric Mapping method will be applied to graphically compare kinematic and kinetic data across the entire gait cycle. QUEST responses will undergo statistical analysis to evaluate patient satisfaction, with scores ranging from 1 (not satisfied) to 5 (very satisfied). Satisfaction scores will be presented as mean and SD values. Significant variations in satisfaction levels between the personalized and existing orthosis will be assessed using a Wilcoxon signed rank test. The anticipation is that the AFOs crafted through this innovative system will either match or outperform existing orthoses in use, with higher patient satisfaction rates. CONCLUSIONS: Embracing the synergy of technology and biomechanics may hold the key to revolutionizing orthotic design, with the potential to set new standards in patient-centered orthotic solutions. However, as with all innovations, a balanced approach, considering both the technological possibilities and individual patient needs, will be paramount to achieving optimal outcomes. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/52365.

3.
Orphanet J Rare Dis ; 19(1): 151, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594754

RESUMO

BACKGROUND: Inherited retinal diseases (IRDs) are a group of rare degenerative disorders of the retina that can lead to blindness from birth to late middle age. Knowing the target population and its resources is essential to better plan support measures. The aim of this study was to evaluate the socioeconomic characteristics of regions in Portugal where IRD patients reside to inform the planning of vision aid and rehabilitation intervention measures. RESULTS: This study included 1082 patients from 973 families, aged 3 to 92 years, with a mean age of 44.8 ± 18.1 years. Patients living with an IRD were identified in 190 of the 308 municipalities. According to this study, the estimated IRD prevalence in Portugal was 10.4 per 100,000 inhabitants, and by municipalities, it ranged from 0 to 131.2 per 100,000 inhabitants. Overall, regions with a higher prevalence of IRD have a lower population density (r=-0.371, p < 0.001), a higher illiteracy rate (r = 0.404, p < 0.001) and an overall older population (r = 0.475, p < 0.001). Additionally, there is a lower proportion of doctor per capita (r = 0.350, p < 0.001), higher social security pensions beneficiaries (r = 0.439, p < 0.001), worse water quality for human consumption (r=-0.194, p = 0.008), fewer audiences at the cinema (r=-0.315, p < 0.001) and lower proportion of foreign guests in tourist accommodations (r=-0.287, p < 0.001). CONCLUSION: The number of identified patients with IRD varied between regions. Using data from national statistics (PORDATA), we observed differences in socioeconomic characteristics between regions. Multiple targeted aid strategies can be developed to ensure that all IRD patients are granted full clinical and socioeconomic support.


Assuntos
Doenças Retinianas , Pessoa de Meia-Idade , Humanos , Adulto , Portugal/epidemiologia , Doenças Retinianas/epidemiologia , Retina , Fatores Socioeconômicos
4.
Nature ; 628(8009): 746-751, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38658682

RESUMO

The valley degree of freedom1-4 of electrons in materials promises routes towards energy-efficient information storage with enticing prospects for quantum information processing5-7. Current challenges in utilizing valley polarization are symmetry conditions that require monolayer structures8,9 or specific material engineering10-13, non-resonant optical control to avoid energy dissipation and the ability to switch valley polarization at optical speed. We demonstrate all-optical and non-resonant control over valley polarization using bulk MoS2, a centrosymmetric material without Berry curvature at the valleys. Our universal method utilizes spin angular momentum-shaped trefoil optical control pulses14,15 to switch the material's electronic topology and induce valley polarization by transiently breaking time and space inversion symmetry16 through a simple phase rotation. We confirm valley polarization through the transient generation of the second harmonic of a non-collinear optical probe pulse, depending on the trefoil phase rotation. The investigation shows that direct optical control over the valley degree of freedom is not limited to monolayer structures. Indeed, such control is possible for systems with an arbitrary number of layers and for bulk materials. Non-resonant valley control is universal and, at optical speeds, unlocks the possibility of engineering efficient multimaterial valleytronic devices operating on quantum coherent timescales.


Assuntos
Dissulfetos , Molibdênio , Molibdênio/química , Dissulfetos/química , Elétrons , Eletrônica/instrumentação , Fenômenos Ópticos
5.
bioRxiv ; 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38659860

RESUMO

Wolcott-Rallison Syndrome (WRS) is the most common cause of permanent neonatal diabetes mellitus among consanguineous families. The diabetes associated with WRS is non-autoimmune, insulin-requiring and associated with skeletal dysplasia and growth retardation. The therapeutic options for WRS patients rely on permanent insulin pumping or on invasive transplants of liver and pancreas. WRS has a well identified genetic cause: loss-of-function mutations in the gene coding for an endoplasmic reticulum kinase named PERK (protein kinase R-like ER kinase). Currently, WRS research is facilitated by cellular and rodent models with PERK ablation. While these models have unique strengths, cellular models incompletely replicate the organ/system-level complexity of WRS, and rodents have limited scalability for efficiently screening potential therapeutics. To address these challenges, we developed a new in vivo model of WRS by pharmacologically inhibiting PERK in zebrafish. This small vertebrate displays high fecundity, rapid development of organ systems and is amenable to highly efficient in vivo drug testing. PERK inhibition in zebrafish produced typical WRS phenotypes such as glucose dysregulation, skeletal defects, and impaired development. PERK inhibition in zebrafish also produced broad-spectrum WRS phenotypes such as impaired neuromuscular function, compromised cardiac function and muscular integrity. These results show that zebrafish holds potential as a versatile model to study WRS mechanisms and contribute to the identification of promising therapeutic options for WRS.

6.
Biol Sport ; 41(2): 95-103, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38524810

RESUMO

The purpose of this study was three-fold: (i) to compare total distance, high-speed running (HSR) distance, and sprint distance covered per 5-minute epoch by players acting as both starters and substitutes; (ii) to compare the locomotor demands between the moments the players entered the match (45-60, 60-75 and 75-90 minutes); and (iii) to compare the locomotor demands of the players between the variations of the within- and between-playing positions. Twenty-one male professional soccer players competing in the Professional Premier League of one of the European countries were observed over sixteen official matches. The players were monitored during all matches using a Global Navigation Satellite System. The measures collected were total distance (TD; m), distance in HSR, sprint distance, HSR, and sprint counts. Considering the comparisons between the splits over the second half of match play, a significant difference between the starters and the substitutes was observed only for sprint distance in the 90-95 minute split (Z = -2.023; p = 0.043). Moreover, no substantial differences were found between the moment the substitute player entered the match regarding total distance (H = 2.650; p = 0.266), HSR distance (H = 1.738; p = 0.419), and sprint distance (H = 0.048; p = 0.976). However, the comparison of between-playing positions revealed considerable differences in total distance (H = 29.246; p < 0.001), and HSR distance (H = 12.153; p = 0.002) covered by the players acting as starters. In contrast, for substitute players, such differences were reported in HSR distance (H = 27.892; p < 0.001) and sprint distance (H = 15.879; p < 0.001). In conclusion, this study suggests that acting as a starter or a substitute does not significantly affect the intensity of effort except during the last periods of match play. However, the contextual factor of performing in a specific playing position plays a significant role both for starters and substitutes.

7.
Biol Sport ; 41(2): 185-199, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38524823

RESUMO

This descriptive study aimed to investigate the current practices of Portuguese and Brazilian soccer coaches in the design and implementation of small-sided games (SSGs) in soccer. A total of 187 male coaches participated in the online survey, consisting of 82 Portuguese and 105 Brazilian individuals. These coaches held various positions within the technical staff, with 63 serving as head coaches, 38 as assistant coaches, 38 as physical trainers, and 48 in other roles related to the technical staff. Additionally, the participants represented both youth (n = 102) and adult competitive levels (n = 59), along with some who were not currently associated with a specific group. The survey consisted of 32 questions divided into three main sections: (i) the timing of SSG application, (ii) the methods used for applying SSGs, and (iii) the reasons for applying SSGs. The Chi-square test revealed a statistically significant association between nationality and the frequency of SSGs used in training sessions during the pre-season (p = 0.039) and in-season (p < 0.001). Moreover, significant association between nationality and the time allocated to employing SSGs for targeting aerobic training (p < 0.001) was found. There was a significant association between nationality and the weekly frequency of SSGs use for targeting sprint training (p = 0.019). The Chi-square test identified significant associations between nationality and the use of SSGs for targeting technical training (p = 0.002), as well as for tactical training (p = 0.002). In summary, this study underscores that SSGs are primarily employed to enhance aerobic fitness, change of direction, technical skills, and tactical behaviors. Coaches generally favor employing SSGs two to three times a week, with typical sessions lasting between 16 to 30 minutes. Notably, the major discrepancies between nationalities lie in the importance assigned to the use of SSGs. However, in practice, the formats and objectives for implementing SSGs remain relatively similar.

8.
Sensors (Basel) ; 24(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38474907

RESUMO

When a limb suffers a fracture, rupture, or dislocation, it is traditionally immobilized with plaster. This may induce discomfort in the patient, as well as excessive itching and sweating, which creates the growth of bacteria, leading to an unhygienic environment and difficulty in keeping the injury clean during treatment. Furthermore, if the plaster remains for a long period, it may cause lesions in the joints and ligaments. To overcome all of these disadvantages, orthoses have emerged as important medical devices to help patients in rehabilitation, as well as for self-care of deficiencies in clinics and daily life. Traditionally, these devices are produced manually, which is a time-consuming and error-prone method. From another point of view, it is possible to use imageology (X-ray or computed tomography) to scan the human body; a process that may help orthoses manufacturing but which induces radiation to the patient. To overcome this great disadvantage, several types of 3D scanners, without any kind of radiation, have emerged. This article describes the use of various types of scanners capable of digitizing the human body to produce custom orthoses. Studies have shown that photogrammetry is the most used and most suitable 3D scanner for the acquisition of the human body in 3D. With this evolution of technology, it is possible to decrease the scanning time and it will be possible to introduce this technology into clinical environment.


Assuntos
Fraturas Ósseas , Aparelhos Ortopédicos , Humanos , Tomografia Computadorizada por Raios X , Tecnologia , Extremidades
9.
Sci Prog ; 107(1): 368504241231657, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38444385

RESUMO

The primary objective of this study was to systematically investigate the physiological and physical fitness adaptations resulting from small-sided games (SSGs) training programs in basketball players competing at youth competitive levels, as compared to other training approaches and/or control groups. To achieve this, we conducted a literature search on PubMed, Scopus, SPORTDiscus, and Web of Science, adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. From the initial 626 studies retrieved, five were considered eligible for the current study. Among the five included articles, four conducted comparisons between the effects of SSGs and running-based high-intensity interval training. Regarding this, the four studies revealed a significant improvement in the final velocity during the 30-15 Intermittent Fitness Test, ranging from 4.07% to 7.29% following SSG-based interventions. This improvement was not significantly different from the comparator group. Additionally, two studies indicated that the SSGs group showed a significant advantage in change-of-direction time, with improvements ranging from -2.11% to 6.69% after interventions, and these results were not significantly different from the comparator group. However, the effects on repeated sprint ability yielded contradictory findings; two studies reported significant improvements ranging from -5.00% to -2.16%, while two others did not show significant effects following SSGs-based interventions. Similarly, in the linear sprint, the results of SSGs-based interventions were inconsistent. In summary, based on the available research, it can be concluded that SSG-based training is effective in significantly enhancing aerobic performance and change of direction, comparable to alternative approaches. However, the effects on repeated sprint ability and sprint performance are not consistently demonstrated.


Assuntos
Basquetebol , Condicionamento Físico Humano , Adolescente , Humanos , Basquetebol/fisiologia , Exercício Físico , Adaptação Fisiológica
10.
Heliyon ; 10(5): e27203, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38449617

RESUMO

Purpose: This study aimed to: (i) analyze the changes in physical fitness and body composition following a 4-month intervention of small-sided games (SSG) training; and (ii) analyze the association between internal and external training loads and the observed changes in physical fitness and body composition among sedentary young adults. Methods: Sixty sedentary individuals (males: 30; females: 30) participated in this randomized controlled trial study. Physical fitness and body composition parameters were assessed at the 1st, 8th weeks, and 16th weeks after a SSG intervention. Results: Significant main effects of time and gender on overall physical fitness parameters, with a notable time-group interaction were observed. For body composition measures, we found significant main effects of time, group, and gender. Furthermore, we identified significant correlations between shuttle run, handgrip, and vertical jump performance, and the time spent at VO2max (TVO2max) during SSG (r = -0.779, p = 0.001; r = -0.788, p = 0.001; r = 0.692, p = 0.004, respectively). Handgrip strength exhibited significant correlations with heat exhaustion (HE) and total distance (TD) during SSG (r = -0.616, p = 0.014; r = -0.629, p = 0.012). Similarly, we observed significant correlations between hip perimeter (HP), skinfolds (SF), waist-to-hip ratio (W:H), and TVO2max (r = 0.624, p = 0.013; r = 0.663, p = 0.007; r = 0.535, p = 0.040, respectively). Conclusion: This study indicates that the intensity achieved during SSG plays a crucial role in fostering positive adaptations in aerobic capacity, maximal strength, and jumping performance in recreational soccer. Therefore, practitioners should ensure that SSG formats generate the required stimulus to sustain prolonged periods within VO2max zones.

11.
Clin Transl Radiat Oncol ; 45: 100731, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38304241

RESUMO

Objective: To reduce liver and lung dose during right breast irradiation while maintaining optimal dose to the target volume. This dose reduction has the potential to decrease acute side effects and long-term toxicity. Materials and Methods: 16 patients treated with radiation therapy for localized carcinoma of the right breast were included retrospectively. For the planning CT, each patient was immobilised on an indexed board with the arms placed above the head. CT scans were acquired in free-breathing (FB) as well as with deep inspiration breath hold (DIBH). Both scans were acquired with the same length. Planning target volumes (PTV's) were created with a 5 mm margin from the respective clinical target volumes (CTV's) on both CT datasets. The liver was outlined as scanned. Dose metrics evaluated were as follows: differences in PTV coverage, dose to the liver (max, mean, V90%, V50%, V30%), dose to lung (mean, V20Gy, relative electron density) and dose to heart (Dmax). The p-values were calculated using Wilcoxon signed-rank tests. A p-value was significant when <0.05. Results: Differences in PTV coverage between plans using FB and DIBH were less than 2 %. Maximum liver dose was significantly less using DIBH: 17.5 Gy versus FB: 40.3 Gy (p < 0.001). The volume of the liver receiving 10 % of the dose was significantly less using DIBH with 1.88 cm3 versus 72.2 cm3 under FB (p < 0.001). The absolute volume receiving 20 Gy in the right lung was larger using DIBH: 291 cm3 versus 230 cm3 under FB (p < 0.001) and the relative volume of lung receiving dose greater than 20 Gy was smaller with DIBH: 11.5 % versus 14 % in FB (p = 0.007). The relative electron density of lung was significantly less with DIBH: 0.59 versus 0.62 with FB, (p < 0.001). This suggests that the lung receives less dose due to its lower density when using DIBH. Conclusion: Radiation of the right breast using DIBH spares liver and lung tissue significantly and thus carries the potential of best practice for right sided breast cancer.

12.
Sci Prog ; 107(1): 368504231224606, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38196181

RESUMO

The objectives of this study were twofold: (a) to analyze the variability of 3v3 and 5v5 small-sided games (SSG) formats in sedentary young adults, and (b) to compare the physiological and locomotor demands of 3v3 and 5v5 SSG formats while considering variations based on sex. The study followed a longitudinal design over 4 months. Thirty sedentary young adults with a mean age of 20.2 ± 1.0 years, height of 1.67 ± 0.06 m, and body mass of 86.3 ± 11.8 kg were included in the study. The participants engaged in 3v3 and 5v5 SSG formats, with each format being played 10 times per month. During each session, heart rate (HR), rate of perceived exertion (RPE), and total distance were measured and analyzed. The within-player variability for HR ranged from a minimum of 1.6% to a maximum of 2.8% (considering the levels at each month), while the between-players variability for HR ranged from a minimum of 1.4% to a maximum of 2.6% (considering the levels at each month). Similar variability patterns were observed for the other outcomes. In terms of comparisons between the formats, the 3v3 format resulted in higher RPE than the 5v5 format for both male (p = 0.006) and female (p = 0.628) participants, as well as for the other outcome measures. In summary, these findings highlight the reproducibility of physiological responses in 3v3 and 5v5 SSG among sedentary individuals. Notably, the 3v3 format consistently induced higher RPE levels. These findings underscore the importance of programming SSG based on sex and format preferences for optimizing exercise outcomes in sedentary.


Assuntos
Futebol , Humanos , Feminino , Masculino , Adulto Jovem , Adulto , Reprodutibilidade dos Testes , Exercício Físico
13.
Nature ; 626(7997): 66-71, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38233521

RESUMO

Ever since its discovery1, the notion of the Berry phase has permeated all branches of physics and plays an important part in a variety of quantum phenomena2. However, so far all its realizations have been based on a continuous evolution of the quantum state, following a cyclic path. Here we introduce and demonstrate a conceptually new manifestation of the Berry phase in light-driven crystals, in which the electronic wavefunction accumulates a geometric phase during a discrete evolution between different bands, while preserving the coherence of the process. We experimentally reveal this phase by using a strong laser field to engineer an internal interferometer, induced during less than one cycle of the driving field, which maps the phase onto the emission of higher-order harmonics. Our work provides an opportunity for the study of geometric phases, leading to a variety of observations in light-driven topological phenomena and attosecond solid-state physics.

15.
Heliyon ; 9(11): e22041, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38045141

RESUMO

Aerobic fitness is a critical aspect of overall health and well-being, essential for maintaining a high quality of life. Unfortunately, sedentary behavior has been on the rise among young adults, and this has had a negative impact on their aerobic fitness levels. Therefore, it is crucial to identify enjoyable physical exercise training programs that can play a pivotal role in improving aerobic fitness. The objective of this study was to systematically review the experimental studies concerning the impact of small-sided games (SSGs) training programs, implemented across various team sports, on the enhancement of aerobic fitness in a youth sedentary population. A literature search was conducted in PubMed, Scopus, and the Web of Science on August 01, 2023. Our eligibility criteria focused on studies involving sedentary youth populations (aged <18 years) as the target population. These studies needed to incorporate interventions based on SSGs as the intervention of interest, comparing them to passive or control groups as the comparator. The primary outcomes of interest were related to maximal oxygen uptake (VO2max), assessed either directly or indirectly, or the results of field-based cardiorespiratory tests. We specifically considered two- or multi-arm randomized controlled studies as the study design of interest. Out of the initial pool of 1980 studies, we reviewed 38 full-text articles, ultimately selecting and analyzing 13 studies for inclusion in our review. Among the studies included, a total of 1281 participants were enrolled in SSG-based interventions, while 744 participants acted as part of the control groups. Regarding the impact on VO2max, the six studies that investigated this outcome showed varying improvements, ranging from 2.2 % to 31.3 % when participants were exposed to SSGs. In terms of the outcome related to endurance performance in field-based tests, the eight studies that examined this aspect found that participants exposed to SSGs showed improvements ranging from 0.1 % to 79.8 %. In conclusion, this systematic review suggests that SSG-based interventions conducted among sedentary youth populations can play a positive role in improving their aerobic fitness. This improvement in aerobic fitness can have potential positive impacts on their overall health and quality of life.

16.
Nat Commun ; 14(1): 8421, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38110439

RESUMO

High-harmonic generation in solids allows probing and controlling electron dynamics in crystals on few femtosecond timescales, paving the way to lightwave electronics. In the spatial domain, recent advances in the real-space interpretation of high-harmonic emission in solids allows imaging the field-free, static, potential of the valence electrons with picometer resolution. The combination of such extreme spatial and temporal resolutions to measure and control strong-field dynamics in solids at the atomic scale is poised to unlock a new frontier of lightwave electronics. Here, we report a strong intensity-dependent anisotropy in the high-harmonic generation from ReS2 that we attribute to angle-dependent interference of currents from the different atoms in the unit cell. Furthermore, we demonstrate how the laser parameters control the relative contribution of these atoms to the high-harmonic emission. Our findings provide an unprecedented atomic perspective on strong-field dynamics in crystals, revealing key factors to consider in the route towards developing efficient harmonic emitters.

17.
GE Port J Gastroenterol ; 30(Suppl 1): 35-44, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37908740

RESUMO

Endoscopic esophageal stent placement is an effective palliative treatment for malignant strictures and has also been successfully used for benign indications, including esophageal refractory strictures and iatrogenic leaks and perforations. Despite several decades of evolution and the wide variety of esophageal stents available to choose from, an ideal stent that is both effective and without adverse events such as stent migration, tissue ingrowth, or pressure necrosis has yet to be developed. This paper is an overview of how this evolution happened, and it also addresses the characteristics of some of the currently available stents, like their material and construction, delivery device, radial and axial force pattern, covering and size which may help to understand and avoid the occurrence of adverse events. The insertion delivery systems and techniques of placement of an esophageal self-expandable metal stent are reviewed, as well as some tips and tricks regarding placement and management of adverse events.


A colocação endoscópica de próteses esofágicas metálicas auto-expansíveis é um tratamento paliativo eficaz da estenose maligna, tendo também sido usada com sucesso em indicações benignas, como no caso de estenoses refratárias do esófago ou de perfurações e deiscências iatrogénicas. Apesar de várias décadas de evolução e não obstante existir uma grande variedade de escolha de próteses esofágicas, ainda está por desenvolver a prótese ideal que apresente simultaneamente uma eficácia elevada e uma incidência reduzida de complicações como migração, crescimento tecidular ou necrose por pressão. Este artigo fornece uma visão global de como esta evolução ocorreu e aborda as características de algumas das próteses atualmente existentes no mercado, como o seu material e tipo de construção, padrão de força axial e radial, cobertura e dimensões, que poderão ajudar a compreender e a evitar a ocorrência desses eventos adversos. São analisados os sistemas de libertação e técnicas de introdução das próteses metálicas auto-expansíveis, com alguns truques e dicas relativas à colocação das próteses e abordagem de eventos adversos.

18.
ACS Appl Opt Mater ; 1(10): 1661-1669, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37915971

RESUMO

We have established a label-free plasmonic platform that monitors proteolytic activity in real time. The sensor consists of a random array of gold nanorods that are functionalized with a design peptide that is specifically cleaved by thrombin, resulting in a blueshift of the longitudinal plasmon. By monitoring the plasmon of many individual nanorods, we determined thrombin's proteolytic activity in real time and inferred relevant kinetic parameters. Furthermore, a comparison to a kinetic model revealed that the plasmon shift is dictated by a competition between peptide cleavage and thrombin binding, which have opposing effects on the measured plasmon shift. The dynamic range of the sensor is greater than two orders of magnitude, and it is capable of detecting physiologically relevant levels of active thrombin down to 3 nM in buffered conditions. We expect these plasmon-mediated label-free sensors to open the window to a range of applications stretching from the diagnostic and characterization of bleeding disorders to fundamental proteolytic and pharmacological studies.

19.
Heliyon ; 9(10): e20920, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37916076

RESUMO

Monitoring locomotor demands in team sports becomes popular in professional and recreational daily activities. Precise measurements are main of importance in training routine. The aim of this study is three-fold: (i) analyze the validity of Polar M400 Global Positioning System (GPS) watches for measuring distances covered in team sports simulation cycle; (ii) testing inter-unit reliability of two devices attached during testing; and (iii) testing inter-session reliability for the same simulation cycle. Methods: Twenty-one team athletes (age: 24.5 ± 5.2 years; body mass: 71.8 ± 5.7 kg; height: 176.5 ± 4.3 cm) were tested in the team sport simulation cycle (TSSC). Two Polar M400 sport watches were used by each player on their wrists at the same time. The data obtained from Polar M400 were compared to the reference fixed distance of the TSSC to determine the watch validity. Inter-session reliability was also tested using the two watches in two different sessions. Results: No significant differences between the reference value and the watches (F = 1.086; p = 0.368; ηp2 ≤0.042) were found. The %CV (0.03-0.05%) and SEM (0.05-0.09) values found for all considered groups confirmed good levels of reliability of the Polar M400 to measure total distance. Conclusions: The Polar M400 is a valid and reliable watch for measuring the distances covered by team sport athletes. Both coaches and athletes can monitor the distances covered with accuracy and precision, through the use of the Polar M400 sport watch.

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