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1.
Behav Res Methods ; 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38627322

RESUMEN

Computer code plays a vital role in modern science, from the conception and design of experiments through to final data analyses. Open sharing of code has been widely discussed as being advantageous to the scientific process, allowing experiments to be more easily replicated, helping with error detection, and reducing wasted effort and resources. In the case of psychology, the code used to present stimuli is a fundamental component of many experiments. It is not known, however, the degree to which researchers are sharing this type of code. To estimate this, we conducted a survey of 400 psychology papers published between 2016 and 2021, identifying those working with the open-source tools Psychtoolbox and PsychoPy that openly share stimulus presentation code. For those that did, we established if it would run following download and also appraised the code's usability in terms of style and documentation. It was found that only 8.4% of papers shared stimulus code, compared to 17.9% sharing analysis code and 31.7% sharing data. Of shared code, 70% ran directly or after minor corrections. For code that did not run, the main error was missing dependencies (66.7%). The usability of the code was moderate, with low levels of code annotation and minimal documentation provided. These results suggest that stimulus presentation code sharing lags behind other forms of code and data sharing, potentially due to less emphasis on such code in open-science discussions and in journal policies. The results also highlight a need for improved documentation to maximize code utility.

2.
Sci Rep ; 12(1): 4191, 2022 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-35264706

RESUMEN

Filtering facepiece respirators (FFRs) provide effective protection against diseases spread through airborne infectious droplets and particles. The widespread use of FFRs during the COVID-19 pandemic has not only led to supply shortages, but the disposal of single-use facemasks also threatens the environment with a new kind of plastic pollution. While limited reuse of filtering facepiece respirators has been permitted as a crisis capacity strategy, there are currently no standard test methods available for decontamination before their repeated use. The decontamination of respirators can compromise the structural and functional integrity by reducing the filtration efficiency and breathability. Digital segmentation of X-ray microcomputed tomography (microCT) scans of the meltblown nonwoven layers of a specific N95 respirator model (Venus-4400) after treatment with one and five cycles of liquid hydrogen peroxide, ultraviolet radiation, moist heat, and aqueous soap solution enabled us to perform filtration simulations of decontaminated respirators. The computed filtration efficiencies for 0.3 µm particles agreed well with experimental measurements, and the distribution of particle penetration depths was correlated with the structural changes resulting from decontamination. The combination of X-ray microCT imaging with numerical simulations thus provides a strategy for quantitative evaluation of the effectiveness of decontamination treatments for a specific respirator model.


Asunto(s)
Descontaminación/métodos , Máscaras , COVID-19/prevención & control , COVID-19/virología , Detergentes/química , Equipo Reutilizado , Filtración , Humanos , Peróxido de Hidrógeno/farmacología , Máscaras/virología , Modelos Teóricos , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/aislamiento & purificación , Rayos Ultravioleta , Microtomografía por Rayos X
3.
Hum Vaccin Immunother ; 17(9): 3239-3246, 2021 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-34076556

RESUMEN

Objective: At a large public university, we aimed to evaluate an intervention designed to increase serogroup B meningococcal (MenB) vaccine uptake and awareness.Methods: Using a pretest-posttest design with a double posttest, we evaluated an intervention conducted by a local foundation and the Florida Department of Health that distributed MenB vaccine on campus and conducted an educational campaign. Prior to intervention activities, we recruited students to complete a survey about their MenB knowledge and attitudes. For survey participants who provided contact information, we sent two follow-up surveys and assessed MenB vaccine records. We used chi-square tests, adjusted for nonindependence, to compare preintervention to postintervention (three-month and one-year) vaccination and attitudes.Results: Among the 686 students with accessible vaccine records, MenB vaccine initiation increased 9% (from 24% to 33%) and completion increased 8% (from 13% to 21%) from before the intervention to one year after the intervention. When restricting to students who completed the relevant follow-up surveys, the percentage of students who heard of the MenB vaccine increased by 15% (p > .001) from before the intervention to three months after (n = 188 students) and maintained a 10% increase (p > .001) one year after the intervention (n = 261 students). Among students that heard of the MenB vaccine, the percentage of students who thought they needed the MenB vaccine even though they received the MenACWY increased 14% (p = .03) by the three-month postintervention survey and up to 18% by the one-year follow-up (p = .002).Conclusions: A university-wide, on-campus vaccination and educational campaign increased college students' MenB vaccine initiation, completion, and knowledge.Clinicaltrials.gov ID: NCT02975596.


Asunto(s)
Infecciones Meningocócicas , Vacunas Meningococicas , Neisseria meningitidis Serogrupo B , Neisseria meningitidis , Humanos , Universidades , Vacunación
4.
J Colloid Interface Sci ; 598: 93-103, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-33894618

RESUMEN

HYPOTHESIS: Self-similarity is a scale-invariant irregularity that can assist in designing a robust superhydrophobic material. A combinatorial design strategy involving self-similarity and dual-length scale can be employed to create a new library of a doubly re-entrant, disordered, and porous network of superhydrophobic materials. Asymmetric wettability can be engineered in nonwoven materials by rendering them with superhydrophobic characteristics on one side. EXPERIMENTS: A facile, scalable, and inexpensive spray-coating technique was used to decorate the weakly hydrophobicstearate-treatedtitanate nanowires (TiONWs)over the self-similar nonwoven material. Laser scanning confocal microscopy was employed to image the impalement dynamics in three dimensions. With the aid of X-ray microcomputed tomography analysis, the three-dimensional (3D) nonwoven structural parameters were obtained and analyzed. The underwater superhydrophobic behavior of the prepared samples was investigated. FINDINGS: A classic 'lotus effect' has been successfully endowed in self-similar nonwoven-titanate nanostructured materials (SS-Ti-NMs) from a nonwoven material that housed the air pockets in bulk and water repellent TiONWs on the surface. The finer fiber-based SS-Ti-NMs exhibited lower roll-off angles and a thinner layer of water on its surface. An asymmetric wettability and the unusual display of underwater superhydrophobic behavior of SS-Ti-NMs have been uncovered.

5.
J Exp Psychol Learn Mem Cogn ; 47(8): 1246-1263, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33539166

RESUMEN

Visual statistical learning (VSL) occurs when participants are exposed to spatially or temporally ordered stimuli, and become increasingly sensitive to them without explicitly realizing the hidden regularities. In the temporal domain of VSL, participants are usually exposed to shape-triplets, followed by the use of familiarity judgments and recognition tasks to directly probe VSL. Other methods, such as the rapid serial visual presentation (RSVP) task, indirectly probe the learning of temporal sequences, and provide evidence of learning within the triplets. Despite the RSVP's success, however, previous implementations of the RSVP task have only pseudorandomized the triplets to form the test sequence, such that the task permits only two stream locations for a given target shape (belonging to a certain within-triplet position), out of six available locations. These fixed locations may result in confounded response time (RT) findings and potentially lead to an overestimation of a weak (or nonexistent) VSL effect. In this study, we conduct 4 experiments and show that the previously reported VSL effect in RSVP is eliminated when the RSVP stream is fully counterbalanced (Experiment 1), and resurfaces again when the RSVP stream returns to its original pseudorandomized design (Experiment 2). Importantly, in both, we observe a "stream location effect," where RT gradually becomes faster to reflect the hazard rate of target appearance, which may have been the factor driving previously reported VSL effects. Follow-up experiments show that results from Experiment 1 are not due to the absence of implicit learning (Experiment 3), although the stream location effect can occur without any learning, suggesting that it is something inherent to the RSVP task (Experiment 4). Together, these results identify an influential effect, the stream location effect, inherently present in the RSVP task, and show how misinforming the RSVP task can be, when not used with properly controlled parameters, and demand a reexamination of the effects found in previous studies which could have been the effect of detection stream locations, misconstrued as VSL. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Asunto(s)
Artefactos , Aprendizaje Espacial , Humanos , Juicio , Tiempo de Reacción , Reconocimiento en Psicología
6.
J Community Health ; 46(4): 808-816, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33389475

RESUMEN

Serogroup B meningococcal disease (MenB) causes almost 60% of meningitis cases among adolescents and young adults. Yet, MenB vaccine coverage among adolescents remains below 10%. Since parents are the primary medical decision makers for adolescents, we examined MenB vaccination rates and parent attitudes about meningitis and the MenB vaccine. In 2018, in conjunction with a county-wide, school-based immunization campaign, we conducted a mixed methods study among parents of 16- to 17-year-olds. We facilitated focus groups asking parents about their knowledge of meningitis and reactions to educational materials and sent behavioral surveys based on Health Belief Model constructs to parents through the county high school system. Parents in three focus groups (n = 8; participation rate = 13%) expressed confusion about their child's need to receive the MenB vaccine in addition to the meningococcal conjugate vaccine (MenACWY), but conveyed strong trust in their physicians' recommendation. Among survey participants (n = 170), 70 (41%) had heard of the MenB vaccine. Among those 70 parents, the most common barriers to vaccination were concerns about side effects (55%) and uncertainty of susceptibility due to receipt of the MenACWY vaccine (30%). The percentage of teens that received at least one dose of the MenB vaccine was 50% (n = 35) by parent report and 23% (n = 16) by state vaccination records. Parents demonstrated uncertainty and confusion about the MenB vaccine particularly due to the existence of another meningitis vaccine and limited health care provider recommendations. Confirmatory studies of parent confusion about the MenB vaccine are needed to develop interventions.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Infecciones Meningocócicas , Vacunas Meningococicas , Neisseria meningitidis Serogrupo B , Padres , Adolescente , Humanos , Infecciones Meningocócicas/prevención & control , Instituciones Académicas , Estudiantes , Vacunación , Adulto Joven
7.
J Mech Behav Biomed Mater ; 112: 104069, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32957055

RESUMEN

Biomaterials are porous and three-dimensional (3D) templates, which are used as biological substitutes in tissue engineering. Targeting the optimal design of biomaterials requires a synergy between mechanical, porous, mass transport, and biological properties. To address this challenge, we propose a non-periodic meta-biomaterial in the form of an out-of-plane auxetic nonwoven scaffold that possesses a 3D interconnected highly porous structure with remarkable mechanical properties corresponding to conventional nonwoven material. A design strategy of utilizing larger fiber diameters to enhance the porosity and permeability characteristics successfully devised the nonwoven scaffold with an extraordinary out-of-plane auxetic effect. In situ tensile-X-ray microcomputed tomography (microCT) analysis has been carried out to monitor the variation in the morphological characteristics.


Asunto(s)
Materiales Biocompatibles , Andamios del Tejido , Porosidad , Ingeniería de Tejidos , Microtomografía por Rayos X
9.
Clin Pract Cases Emerg Med ; 4(2): 167-170, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32426663

RESUMEN

Simultaneous hemorrhagic and ischemic strokes have been previously reported in the literature. Typically, these occur in patients secondary to dialysis, cerebral amyloid angiopathy, or thrombotic thrombocytopenic purpura.1,2,3 However, this is the unique case of a 62-year-old Asian female who presented with a hemorrhagic stroke suspected to be secondary to refractory hypertension from intracranial large vessel atherosclerotic flow limiting stenosis, with rapid subsequent large vessel occlusion and ischemic stroke. Questions arise such as ideal blood pressure parameters for dual management, timeliness of computed tomography angiography imaging in the emergency department for detection of large vessel occlusion during intracranial hemorrhage, and subsequent selection of treatment plan in the dual-lesion patient population.

10.
Iperception ; 11(6): 2041669520981094, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33489074

RESUMEN

Investigations of the "fat-face" illusion have unanimously agreed that the illusion is face-specific. Here, we offer several manipulations to highlight that the fat-face illusion is not restricted to the bottom image, isn't a property of internal features, facial contour/texture, and in general isn't even specific to faces. We propose the axis of horizontal asymmetry account to contextualize fat-face illusion as a geometry-led illusion.

11.
Clin Pract Cases Emerg Med ; 3(2): 144-148, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31061972

RESUMEN

Double steal phenomenon is a rare condition where occlusion of the innominate (brachiocephalic) artery leads to hemodynamic changes in which blood flow is shunted from the intracranial circulation down the right vertebral artery and subsequently up the right carotid and subclavian circulation. This is a case of a 67-year-old female presenting emergently with recurrent transient ischemic attacks due to double steal phenomenon. Emergency department recognition of the double steal phenomenon and large vessel occlusion by computed tomography angiogram of the head and neck allowed for early treatment, which was critical in avoiding irreversible cerebral infarction.

12.
J Mech Behav Biomed Mater ; 72: 6-13, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28433000

RESUMEN

Success of tissue engineering relies on the architecture and properties of porous scaffolds. Electrospun nonwoven scaffolds in the form of mats are unique materials due to large surface area to volume ratio, high porosity, versatility in surface functionalities and excellent mechanical properties. Maneuvering the mechanical behavior of the electrospun mat is a major challenge both from theoretical and experimental perspectives. Herein, we report a two-dimensional (2D) analytical model of normalized elastic moduli of electrospun mats by formulating a relationship with the governing fiber and structural parameters. The analytical model of normalized mat modulus has also accounted for fiber curvature in the form of sinusoidal curve along with the specimen dimensions considered during the uniaxial tensile test. A comparison has been made between the magnitudes of normalized mat modulus obtained through predictive modeling and the experimental results adapted from the literature. In general, a good agreement has been found between the theoretical and the experimental results of normalized moduli of electrospun mats. An interplay of some of the governing parameters has been analyzed through parametric analysis. Through theoretical modeling, the normalized amplitude of fiber crimp via fiber diameter along with the aspect ratio of specimen dimensions are observed to be the dominant factors responsible for modulating the normalized mat modulus.


Asunto(s)
Módulo de Elasticidad , Ingeniería de Tejidos , Andamios del Tejido , Porosidad
13.
J Mech Behav Biomed Mater ; 57: 359-64, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26889606

RESUMEN

Anterior cruciate ligament (ACL) is one of the most susceptible ligaments of the knee that can suffer injury. These ruptured ligaments can be treated through surgical intervention using a braided structure that either acts as a substitute graft in isolation or an augmentation device alongside the biological tissue. Therefore, the main objective of the research work is to present an analytical model for predicting the complete set of tensile properties of braided prosthesis consisting of multifilament strands based upon predefined braid geometry and constituent material properties. The model has also accounted for the kinematical changes under defined loading conditions. The research findings have been confirmed by making a comparison between the theoretical and experimental results. The tensile properties of braided prostheses predicted via analytical route matched reasonably well with the experimental results.


Asunto(s)
Ligamento Cruzado Anterior , Ensayo de Materiales , Prótesis e Implantes , Resistencia a la Tracción , Poliésteres , Estrés Mecánico
14.
J Mech Behav Biomed Mater ; 54: 305-15, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26505530

RESUMEN

Anterior cruciate ligament (ACL) is a key fibrous connective tissue that maintains the stability of a knee joint and it is the most commonly injured ligament of the knee. A synthetic prosthesis in the form of a braided structure can be an attractive alternative to biological grafts provided that the mechanical properties can be tailored to mimic the natural ACL. In the present work, the polypropylene based structurally gradient braided prostheses have been designed and developed by understanding their tensile properties. Circular braiding process was employed to fabricate structurally gradient braided prostheses by systematically placing different types of braids in defined set of layers. An analytical model for predicting the tensile properties of structurally gradient braided prostheses has been presented by modifying and combining the existing models available in the literature. Specifically, the full set of stress-strain behaviour of structurally gradient braided prostheses has been computed based upon braid structural characteristics, constituent strand properties and braid kinematics. A triaxial braid in the outer layer of braided prostheses was found to withstand higher tensile stresses in comparison to a biaxial braid having same structural characteristics. A comparison has been made between the theoretical and experimental results of tensile properties of structurally gradient braided prostheses. The tensile properties of structurally gradient braided prostheses predicted through analytical route matched reasonably well with the experimental results.


Asunto(s)
Ligamento Cruzado Anterior , Ensayo de Materiales , Prótesis e Implantes , Resistencia a la Tracción , Humanos , Estrés Mecánico
15.
Mater Sci Eng C Mater Biol Appl ; 48: 453-6, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25579946

RESUMEN

Sutures are the materials used for wound closure that are caused by surgery or trauma. The main pre-requisite to the success of the suture is to obtain ultimate level of tensile properties with defined geometrical constraints. In this communication, the model for tensile properties of braided sutures has been proposed by elucidating the most important geometrical and material parameters. The model has accounted for the kinematical changes occurring in the braid and constituent strand geometries under defined level of strain. A comparison has been made between the theoretical and experimental results of stress-strain characteristics of braided sutures.


Asunto(s)
Modelos Teóricos , Estrés Mecánico , Suturas , Resistencia a la Tracción , Humanos
16.
Mater Sci Eng C Mater Biol Appl ; 40: 135-41, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24857475

RESUMEN

The present investigation involves the preparation and characterisation of silver containing nanogels and their incorporation onto the surface of woven fabrics so that they can be potentially used in biomedical applications such as wound dressings. These silver nanoparticles were mixed with N-isopropylacrylamide (NIPAM) based nanogels during and at the end of polymerisation process prior to their application onto the fabrics. NIPAM based nanogels were found to have a peak of lower critical solution temperature (LCST) that is close to the human body temperature. These nanogels were applied on cotton fabrics and cured for 15 h at 30°C. Silver based nanogels were padded onto the fabrics followed by drying at 30°C overnight. Scanning electron microscopy images have shown excellent distribution of silver nanoparticles on the fabric surface. EDX analysis was also conducted to confirm the presence of silver particles on the fabric surface. The results showed that a cotton fabric treated with silver based nanogels prevented the growth of bacteria, i.e. Gram-positive (Staphylococcus epidermidis) and Gram-negative (Escherichia coli), on whereas the control cotton fabric samples exhibited considerable level of bacterial growth. Specifically, the nanogels in which the silver particles were added during the polymerisation process were observed to have higher antibacterial efficacy towards both types of bacteria.


Asunto(s)
Antibacterianos/química , Geles/química , Nanoestructuras/química , Acrilamidas/química , Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Humanos , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Nanoestructuras/toxicidad , Plata/química , Staphylococcus epidermidis/efectos de los fármacos , Temperatura
17.
Langmuir ; 28(6): 3285-9, 2012 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-22251513

RESUMEN

Electrospun nonwoven mats exhibiting extreme hydrophobicity have recently attracted much attention for their use in a wide range of applications. These materials are highly heterogeneous and irregular in structure, and accordingly, the design parameters of such materials need to be carefully chosen for obtaining higher apparent contact angles along with the robust composite solid-liquid-vapor interface. Here, we present two dimensionless design parameters, namely, the spacing ratio and pressure difference across the liquid-vapor interface, for enhancing the stability of the Cassie regime. These design parameters are essentially dependent upon the structural characteristics of the electrospun mat and equilibrium contact angle of the liquid. Interestingly, the stability of the composite interface is a trade-off between these dimensionless parameters. Moreover, the pressure difference across the interface can significantly increase by reducing the fiber diameter to nanoscale. The stability of the Cassie state in an electrospun nonwoven mat consisting of lower fiber volume fractions at the nanostructural scale can restore superhydrophobicity even after the impact of a rainfall.


Asunto(s)
Nanoestructuras/química , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Teóricos
18.
Am J Emerg Med ; 29(5): 482-8, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20825816

RESUMEN

OBJECTIVE: We sought to determine the agreement of physician estimates compared with Broselow tape measurements in accurately determining children's weights. Our secondary objective was to evaluate whether physician adjustment of the Broselow tape weight measurement is a better estimate of pediatric weight compared with either method alone. METHODS: This cross-sectional study was conducted in the emergency department (ED) of a tertiary children's hospital. Children between the ages of 0 and 14 years consecutively registered in the pediatric ED were eligible for enrollment. Height, weight, body mass index, and Broselow tape measurement were obtained for all subjects. Blinded ED physicians provided estimates for weight and body habitus for enrolled subjects. Physicians next were given the Broselow weight measurement and then submitted a second, amended estimate (hybrid). Percentage differences were used to analyze the discrepancy between estimates and actual weight. Specifically examined were the proportion of estimates that fell within 10% of the patients' actual body weights. RESULTS: A total of 372 subjects met the inclusion criteria. Mean age was 45.7 months, mean body mass index was 17.4, mean weight was 16.8 kg, and 39 participants (18.1%) met the definition for obese. Broselow estimates were within 10% of actual weight 63% of the time, physician estimates were within 10% of the actual weight 43% of the time and hybrid estimates 55% of the time. Based on average mean percent error, compared with actual weight, Broselow differed by 10.8% (95% confidence interval [CI], 9.7-12), hybrid estimate by 11.3% (95% CI, 10.3-12.2), and physician estimate by 16.2% (95% CI, 14.7-17.7). The Broselow tape was significantly worse than physician estimate for obese patients: 26.4% (95% CI, 19.7-33.1) versus 16.0% (95% CI, 12.3-19.8). CONCLUSION: The Broselow tape generally has greater agreement with actual weight than physician visual estimation, except for obese children. Physician adjustment of the Broselow measurement also proved to be comparable to the Broselow tape.


Asunto(s)
Peso Corporal , Adolescente , Antropometría/instrumentación , Estatura , Índice de Masa Corporal , Niño , Preescolar , Estudios Transversales , Servicio de Urgencia en Hospital , Femenino , Humanos , Lactante , Masculino , Obesidad/diagnóstico
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