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1.
Nanoscale ; 16(8): 4299-4307, 2024 Feb 22.
Article in English | MEDLINE | ID: mdl-38353593

ABSTRACT

Detecting airflow turbulence precursors promptly is crucial for ensuring flight safety and control. The initial stages of turbulence involve small reverse flows with random velocities and directions, which are not easily detected by existing airflow sensors. In this study, we designed a bionic, sensitivity-enhanced, bi-directional airflow sensor (BSBA) by incorporating bio-inspired circular tip slits and enlarging the central part of the cruciform beam structure. The BSBA exhibits a rapid response time (24.1 ms), high sensitivity (1.36 mV m-1 s-1), consistent detection of forward and backward airflow (correlation coefficient of 0.9854), and a low airflow detection threshold (1 ml). With these features, the proposed sensor can rapidly and accurately measure slight variations in the oscillating airflow, flow field, and contact force. The BSBA also achieves transparent obstacle detection on a quadrotor, even in visually challenging environments, by capturing minute changes in the flow fields produced by the quadrotor when encountering obstacles. The sensor's high sensitivity, consistent bi-directional detection, and fast response give it significant potential for enhancing safety in aircraft control systems.

2.
J Interpers Violence ; 39(5-6): 1014-1034, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37791486

ABSTRACT

Aggressive behavior is considered one of the indicators of maladjustment and increases during the transition to college. Previous studies have demonstrated that having identity fusion with particular social groups significantly predicts college adjustment among freshmen. However, the relationship between identity fusion and aggressive behavior in college freshmen has rarely been studied. Thus, guided by the frustration-aggression theory, this study aimed to explore the association between identity fusion with class and aggressive behavior among Chinese college freshmen and examine the potential mediating roles of depressive mood and sleep quality. A cross-sectional survey study was carried out among 1,037 Chinese college freshmen (Mage = 19.56, SD = 1.068, 29.12% males). Class identity fusion, depressive mood, sleep quality, and aggressive behavior were measured via four self-reported questionnaires. Structural equation modeling was used to test the mediation model. Analyses showed that identity fusion was negatively related to depressive mood and aggressive behavior and positively correlated with sleep quality. The results also revealed that the direct effect of identity fusion on aggressive behavior was significant, and identity fusion can indirectly affect aggressive behavior not only through the mediation effect of depressive mood but also through the chain mediation effect of depressive mood and sleep quality. Moreover, the mediating effect of depressive mood varied by gender. These findings suggest that strategies that help freshmen promote identity fusion and those that alleviate depressive mood and sleep problem may help reduce aggressive behavior.


Subject(s)
Depression , Sleep Quality , Male , Humans , Young Adult , Adult , Female , Aggression , Cross-Sectional Studies , Students
3.
ACS Nano ; 16(11): 18048-18057, 2022 11 22.
Article in English | MEDLINE | ID: mdl-36255256

ABSTRACT

Microcantilevers are one of the most essential sensitive elements for various mechanical sensors. Their sensing performance determines the index level of a series of sensors. To date, the long-standing trade-off between ultrasensitivity and long-term durability of microcantilevers still remains a challenge. In nature, scorpions can sense vibrations as low as 10 nm amplitude through their circular tip slits sensilla. Such slit sensilla embedded in the exoskeleton of walking legs endure the compressing and stretching of every movement without spontaneous fracture failures. Here, we focused on the structural design of the circular tip slits which concentrate stress effectively and disperse energy smoothly, with the result that the microcantilevers are ultrasensitive and durable simultaneously in a single element. We devised a reproducible circular tip slits cantilever with enhanced sensitivity and ultralow detection limits to monitor 7 nm amplitude vibrations. The sensor possessed excellent durability and remained highly consistent with the correlation coefficient of nearly 0.999 over 100 000 cycles. Furthermore, the circular tip slits cantilever could precisely sense diverse subtle mechanical signals and exhibited potential applications in monitoring respiratory patterns. The simple geometric design can be easily manufactured on various sensory materials for applications requiring ultrahigh sensitivity and long-time durability.


Subject(s)
Spiders , Animals , Scorpions , Vibration , Movement , Pressure
4.
Rev. cuba. oftalmol ; 34(3): e1084, 2021. tab, graf
Article in Spanish | LILACS, CUMED | ID: biblio-1352024

ABSTRACT

Objetivo: Determinar los resultados de la cirugía mínimamente invasiva en pacientes con estrabismos horizontales. Métodos: Se realizó un estudio descriptivo, longitudinal y prospectivo de una serie de 19 pacientes (16 ojos derechos, 17 izquierdos) atendidos en el Servicio de Oftalmología Pediátrica del Instituto Cubano de Oftalmología "Ramón Pando Ferrer", en el periodo comprendido entre junio de 2018 y julio de 2019, a quienes se les realizó cirugía mínimamente invasiva de estrabismo y fueron seguidos por 6 meses. Se evaluaron las variables: tipo de desviación, agudeza visual, signos posoperatorios, ángulo de desviación pre- y posquirúrgico, éxito quirúrgico, fusión, estereopsis y complicaciones. Resultados: El 73,7 por ciento de los pacientes presentaba esotropías; la media de agudeza visual pre- y posoperatoria entre los dos ojos fue muy similar; el signo posoperatorio más frecuente fue la hiperemia conjuntival ligera (75 por ciento ojos derechos y 64,5 por ciento ojos izquierdos) a las 24 horas. Se encontraron diferencias estadísticas (p < 0,001) en el ángulo de desviación horizontal en dioptrías prismáticas, pre- y poscirugía, con el 84,2 por ciento de éxito quirúrgico. El 78,6 y el 80 por ciento de los pacientes con esotropía y exotropías alcanzaron fusión, pero solo lograron estereopsis el 28,5 y el 60 por ciento de ellos respectivamente. La frecuencia de complicaciones ocurrió en el 15,8 por ciento de los pacientes. Conclusiones: Se alcanzaron buenos resultados motores, así como aceptables en los sensoriales en pacientes operados de estrabismos horizontales por cirugía mínimamente invasiva(AU)


Objective: Determine the results of minimally invasive surgery in patients with horizontal strabismus. Methods: A prospective longitudinal descriptive study was conducted of a series of 19 patients (16 right eyes, 17 left eyes) attending the Pediatric Ophthalmology Service at Ramón Pando Ferrer Cuban Institute of Ophthalmology from June 2018 to July 2019. These patients underwent minimally invasive strabismus surgery and were followed up for six months. The variables considered were deviation type, visual acuity, postoperative signs, pre- and postoperative angle of deviation, surgical success, fusion, stereopsis and complications. Results: Of the patients studied, 73.7 percent presented esotropias; mean pre- and postoperative visual acuity was very similar in the two eyes; the most common postoperative sign was slight conjunctival hyperemia (75 percent right eyes and 64.5 percent left eyes) at 24 hours. Statistical differences (p < 0.001) were found in the horizontal angle of deviation in pre- and postoperative prism diopters, with 84.2 percent surgical success. 78.6 percent and 80 percent of the patients with esotropia and exotropia achieved fusion, but only 28.5 and 60 percent of them, respectively, achieved stereopsis. Complications occurred in 15.8 percent of the patients. Conclusions: Good motor results were obtained, as well as acceptable sensory results in patients undergoing minimally invasive horizontal strabismus surgery(AU)


Subject(s)
Humans , Child, Preschool , Child , Adolescent , Adult , Esotropia/etiology , Strabismus/etiology , Minimally Invasive Surgical Procedures/methods , Depth Perception , Epidemiology, Descriptive , Prospective Studies , Longitudinal Studies
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