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1.
Medicine (Baltimore) ; 99(9): e19331, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32118765

RESUMEN

BACKGROUND: Cricothyroidotomy is the final strategy in the "cannot intubate, cannot oxygenate" scenario, but half of needle cricothyroidotomy attempts result in failure. The most frequent complication in needle cricothyroidotomy is posterior tracheal wall injury. We hypothesized that needle length is related to posterior wall injury and compared needle cricothyroidotomy with a commercial kit to a modified shorter needle to evaluate success and posterior wall injury rates. METHODS: The commercial kit has a needle stopper to prevent posterior wall injury, with a penetrating length of 25 mm. We made long stopper to shorten the length by 5 mm (net 20 mm penetrating length). Residents were recruited, received a lecture about cricothyroidotomy and practiced needle cricothyroidotomy using the commercial kit on a simulator. They then performed cricothyroidotomy using the commercial kit or the shorter needle on an ex-vivo porcine larynx covered with artificial skin. An intra-tracheal endoscope recorded the procedure. The video was evaluated for success/failure or posterior wall injury by independent evaluators. Larynxes with a distance from the outer surface to the inner lumen exceeding 13 mm were excluded. The distance in each larynx was measured by dissection after the study. Success and posterior wall injury rates were analyzed using Fisher exact test (P < .05 was statistically significant). RESULTS: Forty-seven residents participated in the study. Data for two residents were excluded. There was no statistically significant difference in success rate between the commercial kit (100%, 45/45) and the shorter needle (91%, 41/45, P = .12). Failure was defined if the needle tip did not reach the lumen in four trials. Cannulated but complicated by posterior wall injury occurred in 33% (15/45) with the commercial kit and 5% (2/43) with the shorter needle (P < .01). CONCLUSION: During needle cricothyroidotomy, force is needed for the needle to penetrate the cricothyroid ligament. The advancing needle sometimes cannot be stopped after penetrating the cricothyroid ligament. These data suggest that needle length is associated with posterior wall injury.


Asunto(s)
Cartílago Cricoides/cirugía , Agujas/efectos adversos , Tráquea/lesiones , Animales , Estudios Cruzados , Modelos Animales de Enfermedad , Diseño de Equipo/métodos , Diseño de Equipo/normas , Agujas/tendencias , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/fisiopatología , Porcinos/lesiones , Enseñanza
2.
PLoS One ; 15(2): e0228536, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32049971

RESUMEN

Recent literature emphasizes the importance of comfort in the design of exosuits and other assistive devices that physically augment humans; however, there is little quantitative data to aid designers in determining what level of force makes users uncomfortable. To help close this knowledge gap, we characterized human comfort limits when applying forces to the shoulders, thigh and shank. Our objectives were: (i) characterize the comfort limits for multiple healthy participants, (ii) characterize comfort limits across days, and (iii) determine if comfort limits change when forces are applied at higher vs. lower rates. We performed an experiment (N = 10) to quantify maximum tolerable force pulling down on the shoulders, and axially along the thigh and shank; we termed this force the comfort limit. We applied a series of forces of increasing magnitude, using a robotic actuator, to soft sleeves around their thigh and shank, and to a harness on their shoulders. Participants were instructed to press an off-switch, immediately removing the force, when they felt uncomfortable such that they did not want to feel a higher level of force. On average, participants exhibited comfort limits of ~0.9-1.3 times body weight on each segment: 621±245 N (shoulders), 867±296 N (thigh), 702±220 N (shank), which were above force levels applied by exosuits in prior literature. However, individual participant comfort limits varied greatly (~250-1200 N). Average comfort limits increased over multiple days (p<3e-5), as users habituated, from ~550-700 N on the first day to ~650-950 N on the fourth. Specifically, comfort limits increased 20%, 35% and 22% for the shoulders, thigh and shank, respectively. Finally, participants generally tolerated higher force when it was applied more rapidly. These results provide initial benchmarks for exosuit designers and end-users, and pave the way for exploring comfort limits over larger time scales, within larger samples and in different populations.


Asunto(s)
Diseño de Equipo , Dispositivo Exoesqueleto , Pierna/fisiología , Mialgia/prevención & control , Comodidad del Paciente , Presión/efectos adversos , Hombro/fisiología , Adulto , Tobillo/fisiología , Fenómenos Biomecánicos , Diseño de Equipo/efectos adversos , Diseño de Equipo/métodos , Dispositivo Exoesqueleto/efectos adversos , Femenino , Marcha/fisiología , Humanos , Masculino , Mialgia/etiología , Comodidad del Paciente/métodos , Robótica/instrumentación , Robótica/métodos , Estrés Mecánico , Muslo/fisiología , Adulto Joven
3.
PLoS One ; 15(2): e0225408, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32023244

RESUMEN

A high-voltage generator (HVG) is an essential part of a radio frequency identification electrically erasable programmable read-only memory (RFID-EEPROM). An HVG circuit is used to generate a regulated output voltage that is higher than the power supply voltage. However, the performance of the HVG is affected owing to the high-power dissipation, high-ripple voltage and low-pumping efficiency. Therefore, a regulator circuit consists of a voltage divider, comparator and a voltage reference, which are respectively required to reduce the ripple voltage, increase pumping efficiency and decrease the power dissipation of the HVG. Conversely, a clock driving circuit consists of the current-starved ring oscillator (CSRO), and the non- overlapping clock generator is required to drive the clock signals of the HVG circuit. In this study, the Mentor Graphics EldoSpice software package is used to design and simulate the HVG circuitry. The results showed that the designed CSRO dissipated only 4.9 µW at 10.2 MHz and that the phase noise was only -119.38 dBc/Hz at 1 MHz. Moreover, the proposed charge pump circuit was able to generate a maximum VPP of 13.53 V and it dissipated a power of only 31.01 µW for an input voltage VDD of 1.8 V. After integrating all the HVG modules, the results showed that the regulated HVG circuit was also able to generate a higher VPP of 14.59 V, while the total power dissipated was only 0.12 mW with a chip area of 0.044 mm2. Moreover, the HVG circuit produced a pumping efficiency of 90% and reduced the ripple voltage to <4 mV. Therefore, the integration of all the proposed modules in HVG ensured low-ripple programming voltages, higher pumping efficiency, and EEPROMs with lower power dissipation, and can be extensively used in low-power applications, such as in non-volatile memory, radiofrequency identification transponders, on-chip direct current DC-DC converters.


Asunto(s)
Suministros de Energía Eléctrica , Diseño de Equipo/métodos , Dispositivo de Identificación por Radiofrecuencia , Programas Informáticos , Electricidad , Ondas de Radio , Transistores Electrónicos
4.
Int J Radiat Oncol Biol Phys ; 106(2): 440-448, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31928642

RESUMEN

PURPOSE: Recent studies suggest that ultrahigh-dose-rate, "FLASH," electron radiation therapy (RT) decreases normal tissue damage while maintaining tumor response compared with conventional dose rate RT. Here, we describe a novel RT apparatus that delivers FLASH proton RT (PRT) using double scattered protons with computed tomography guidance and provide the first report of proton FLASH RT-mediated normal tissue radioprotection. METHODS AND MATERIALS: Absolute dose was measured at multiple depths in solid water and validated against an absolute integral charge measurement using a Faraday cup. Real-time dose rate was obtained using a NaI detector to measure prompt gamma rays. The effect of FLASH versus standard dose rate PRT on tumors and normal tissues was measured using pancreatic flank tumors (MH641905) derived from the KPC autochthonous PanCa model in syngeneic C57BL/6J mice with analysis of fibrosis and stem cell repopulation in small intestine after abdominal irradiation. RESULTS: The double scattering and collimation apparatus was dosimetrically validated with dose rates of 78 ± 9 Gy per second and 0.9 ± 0.08 Gy per second for the FLASH and standard PRT. Whole abdominal FLASH PRT at 15 Gy significantly reduced the loss of proliferating cells in intestinal crypts compared with standard PRT. Studies with local intestinal irradiation at 18 Gy revealed a reduction to near baseline levels of intestinal fibrosis for FLASH-PRT compared with standard PRT. Despite this difference, FLASH-PRT did not demonstrate tumor radioprotection in MH641905 pancreatic cancer flank tumors after 12 or 18 Gy irradiation. CONCLUSIONS: We have designed and dosimetrically validated a FLASH-PRT system with accurate control of beam flux on a millisecond time scale and online monitoring of the integral and dose delivery time structure. Using this system, we found that FLASH-PRT decreases acute cell loss and late fibrosis after whole-abdomen and focal intestinal RT, whereas tumor growth inhibition is preserved between the 2 modalities.


Asunto(s)
Órganos en Riesgo/efectos de la radiación , Terapia de Protones/instrumentación , Traumatismos Experimentales por Radiación/prevención & control , Protección Radiológica/instrumentación , Radioterapia Guiada por Imagen/instrumentación , Abdomen/efectos de la radiación , Animales , Proliferación Celular/efectos de la radiación , Diseño de Equipo/métodos , Estudios de Factibilidad , Femenino , Fibrosis , Rayos gamma , Intestino Delgado/patología , Intestino Delgado/efectos de la radiación , Ratones , Ratones Endogámicos C57BL , Tratamientos Conservadores del Órgano/instrumentación , Tratamientos Conservadores del Órgano/métodos , Órganos en Riesgo/patología , Neoplasias Pancreáticas/radioterapia , Terapia de Protones/métodos , Protección Radiológica/métodos , Radiometría/métodos , Radioterapia Guiada por Imagen/métodos , Dispersión de Radiación , Células Madre/efectos de la radiación , Tomografía Computarizada por Rayos X
5.
AAPS PharmSciTech ; 20(8): 329, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31676991

RESUMEN

The objective of this study was to optimize the performance of a high-efficiency pediatric inhaler, referred to as the pediatric air-jet DPI, using computational fluid dynamics (CFD) simulations with supporting experimental analysis of aerosol formation. The pediatric air-jet DPI forms an internal flow pathway consisting of an inlet jet of high-speed air, capsule chamber containing a powder formulation, and outlet orifice. Instead of simulating full breakup of the powder bed to an aerosol in this complex flow system, which is computationally expensive, flow-field-based dispersion parameters were sought that correlated with experimentally determined aerosolization metrics. For the pediatric air-jet DPI configuration that was considered, mass median aerodynamic diameter (MMAD) directly correlated with input turbulent kinetic energy normalized by actuation pressure and flow kinetic energy. Emitted dose (ED) correlated best with input flow rate multiplied by the ratio of capillary diameters. Based on these dispersion parameters, an automated CFD process was used over multiple iterations of over 100 designs to identify optimal inlet and outlet capillary diameters, which affected system performance in complex and unexpected ways. Experimental verification of the optimized designs indicated an MMAD < 1.6 µm and an ED > 90% of loaded dose. While extrathoracic depositional loss will be determined in future studies, at an operating flow rate of 15 L/min, it is expected that pediatric mouth-throat or even nose-throat aerosol deposition fractions will be below 10% and potentially less than 5% representing a significant improvement in the delivery efficiency of dry powder pharmaceutical aerosols to children.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Inhaladores de Polvo Seco/métodos , Diseño de Equipo/métodos , Hidrodinámica , Administración por Inhalación , Aerosoles , Niño , Sistemas de Liberación de Medicamentos/normas , Inhaladores de Polvo Seco/normas , Diseño de Equipo/normas , Humanos , Tamaño de la Partícula , Polvos
6.
Undersea Hyperb Med ; 46(4): 429-435, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31509899

RESUMEN

Introduction: It is vital to protect divers from the cold, particularly in Arctic conditions. The insulating gas layer within the drysuit is crucial for reducing heat loss. The technical diving community has long claimed the superiority of argon over air as an insulating gas. Although argon is widely used, previous studies have shown no significant differences between the two gases. Owing to its lower heat conductivity, argon should be a better thermal insulating gas than air. Methods: The study aimed to determine whether argon is beneficial for reducing heat loss in divers during development of military drysuit diving equipment in Arctic water temperatures. Four divers completed 14 dives, each lasting 45 minutes: seven dives used air insulation and seven used argon insulation. Rectal and eight skin temperatures were measured from which changes in calculated mean body temperature (MBT) were assessed. Results: There was a significant reduction in area weighted skin temperature over time (0-45 minute) on air dives (ΔTskin = -4.16°C, SE = 0.445, P ⟨ 0.001). On argon dives the reduction was significantly smaller compared to air dives (difference between groups = 2.26°C, SE = 0.358, P ⟨ 0.001). There were no significant changes in rectal temperatures, nor was a significant difference seen between groups. Conclusion: Compared to air, argon may be superior as a drysuit insulating gas in Arctic water temperatures for some divers. Argon used as insulating gas can make diving safer and may diminish the risks of fatal diving accidents and occupational hazard risks in professional diving.


Asunto(s)
Aire , Argón , Buceo , Ropa de Protección , Temperatura Cutánea , Conductividad Térmica , Adulto , Regiones Árticas , Regulación de la Temperatura Corporal , Frío , Diseño de Equipo/métodos , Finlandia , Humanos , Masculino , Persona de Mediana Edad , Personal Militar , Estudios Retrospectivos
7.
Med Sci Monit ; 25: 7175-7181, 2019 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-31549689

RESUMEN

BACKGROUND 3D-printed insoles are widely used. This study was conducted to test a customized three-dimensional (3D)-printed heel support insole based on arch lift and to investigate whether the pressure distribution on the sole was improved while maintaining foot function. MATERIAL AND METHODS The design was based on a 3D plantar contour scanning modeling technique. Thirty healthy male participants walked along a 10-m track under 3 self-controlled interventions. A customized 3D-printed heel support insole based on arch lift was inserted into the socks for the experimental condition A. For condition B, a customized 3D-printed heel-supporting insole was inserted into the socks, and a standardized pre-made heel-supporting insole was inserted into the socks as a control (condition C). We used the Footscan® pressure plate to measure the plantar parameters in the forefoot contact and foot flange phases in each condition. RESULTS Compared with condition B and the control condition, the peak pressure under the heel was significantly lower in condition A (P<0.05), and the peak pressure in the midfoot region was not significantly increased (P>0.05). CONCLUSIONS The biomechanical properties of the customized 3D-printed heel support are better than those of the traditional heel support insole, especially when there is a need for an additional increase in heel height. Patients do not decrease midfoot motion function while using this customized insole.


Asunto(s)
Diseño de Equipo/métodos , Ortesis del Pié/tendencias , Talón/fisiopatología , China , Pie , Voluntarios Sanos , Humanos , Masculino , Presión , Impresión Tridimensional/instrumentación , Zapatos , Caminata
8.
Appl Ergon ; 81: 102881, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31422253

RESUMEN

The aim of this study was to propose a new method for optimizing the touch-screen installation position in order to minimize the physical workload and increase screen visibility. Ten students participated in this study. The participants utilized a touch screen at different installation heights (50, 65, and 80% of stature), tilt angles (0°, 45°, and 90° from the horizontal plane), and having different button sizes (a square with a side of 10, 20, and 30 mm). The joint angles, when using a touch screen, were measured to calculate the joint torque ratios (JTRs). Subjective screen visibility were also determined. The optimal installation position was determined by solving a bi-objective optimization problem consisting of two objective functions. The Pareto optimal solutions for the two objectives showed a range of 1124-1251 mm and 44.4-67.9°. The proposed method determined the optimal installation position of the touch screens.


Asunto(s)
Terminales de Computador , Diseño de Equipo/métodos , Ergonomía/métodos , Análisis y Desempeño de Tareas , Interfaz Usuario-Computador , Adulto , Femenino , Voluntarios Sanos , Humanos , Masculino , Torque , Percepción del Tacto , Carga de Trabajo , Adulto Joven
9.
Appl Ergon ; 81: 102903, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31422260

RESUMEN

Design features of safety work boots have the potential to influence how underground coal miners' feet interact with the challenging surfaces they walk on and, in turn, their risk of slipping. Despite the importance of work boot design in reducing the risk of miners slipping, limited research has investigated how boot design features, such as shaft stiffness and sole flexibility, affect the way miners walk. Therefore, this study aimed to investigate the effects of systematic variations to boot shaft stiffness and sole flexibility on lower limb muscle activity and ankle motion in preparation for initial foot-ground contact when 20 males walked across two simulated coal mining surfaces under four mining boot conditions. It was concluded that a boot which has different flexibility and stiffness between the shaft and sole is a better design option to reduce underground coal miners' slip risk than a boot that has a stiff shaft and stiff sole or flexible shaft and flexible sole.


Asunto(s)
Minas de Carbón , Diseño de Equipo/métodos , Pisos y Cubiertas de Piso , Zapatos , Caminata/fisiología , Accidentes por Caídas/prevención & control , Accidentes de Trabajo/prevención & control , Adulto , Tobillo/fisiología , Simulación por Computador , Pie/fisiología , Humanos , Extremidad Inferior/fisiología , Masculino , Propiedades de Superficie
10.
Appl Ergon ; 81: 102887, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31422265

RESUMEN

The Visual Field (VF) principle has been found to apply in many situations, but has not been tested under many possible conditions of operator posture with different display and control locations. In this research we used four display locations, four control locations relative to a seated operator and tested the strength of population stereotype for six different types of controls with linear displays moving either horizontally or vertically and circular displays with a neutral indicator at the 12, 3, 6 and 9 o'clock positions. Apart from several minor differences in operator responses, the VF principle held up well under all these different display/control relationships. By designing the display/control arrangement to have high stereotype strength, the direction of control movement for a given direction of indicator movement can be selected to comply with the VF principle for producing fewest errors in movement direction.


Asunto(s)
Presentación de Datos , Diseño de Equipo/psicología , Sistemas Hombre-Máquina , Conducta Estereotipada , Campos Visuales , Terminales de Computador , Diseño de Equipo/métodos , Femenino , Humanos , Masculino , Movimiento , Postura , Tiempo de Reacción , Adulto Joven
11.
Appl Ergon ; 81: 102890, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31422279

RESUMEN

A two phase project is described for redesigning and evaluating paramedic response bags, one of the key pieces of equipment used by emergency medical services. Adopting a user-centred approach, Phase I involved first educating active service paramedics about ergonomic principles, and then collaborating with them to conceptualise a new type of response bag, based on separate colour coded kits, each containing related equipment items. Phase II describes a formal evaluation study, involving simulated procedures with a patient mannequin and active service paramedics in a real ambulance. Results indicated subjective preferences for the new bags, where 62% of the paramedics believed it was easier to find equipment in the new bag and 65% preferred the new bags overall. No detrimental effects were attributed to the transition to the new bag. Also discussed are the advantages of the participatory design approach, as well as design guidelines and implications for paramedic operations.


Asunto(s)
Técnicos Medios en Salud/psicología , Servicios Médicos de Urgencia , Diseño de Equipo/psicología , Equipos y Suministros , Ergonomía , Adulto , Diseño de Equipo/métodos , Femenino , Humanos , Masculino , Satisfacción Personal
12.
Medicina (Kaunas) ; 55(8)2019 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-31366186

RESUMEN

Background and objectives: Medical devices such as catheters are used on a large scale to treat heart and cardiovascular diseases. Unfortunately, they present some important drawbacks (structure failure, calcifications, infections, thrombosis, etc.), with the main side effects occurring due to adhesion and proliferation of bacteria and living cells on the surface of the implanted devices. The aim of this work is to modify the surface of polyvinyl chloride (PVC), an affordable biocompatible material, in order to reduce these aforementioned side effects. Materials and Methods: The surface of PVC was modified by depositing a thin layer also of PVC that incorporates an active substance, dicoumarol (a well-known anticoagulant), by spin coating process. The modified surfaces were analyzed by Fourier-transform infrared (FT-IR) microscopy, Fourier-transform infrared (FT-IR) spectroscopy, Ultraviolet-visible spectroscopy (UV-VIS), and Scanning electron microscopy (SEM) in order to determine the surface morphology and behavior. The samples were tested for Gram-positive (S. aureus ATCC 25923) and Gram-negative (P. aeruginosa ATCC 27853) standard strains from American Type Culture Collection (ATCC). Results: The material obtained had a smooth surface with a uniform distribution of dicoumarol, which is released depending on the deposition parameters. The concentration of dicoumarol at the surface of the material and also the release rate is important for the applications for which the surface modification was designed. PVC modified using the proposed method showed a good ability to prevent salt deposition and decreased the protein adhesion, and the resistance to bacterial adherence was improved compared with standard PVC.


Asunto(s)
Dicumarol/uso terapéutico , Cloruro de Polivinilo/efectos adversos , Materiales Biocompatibles , Catéteres/efectos adversos , Catéteres/microbiología , Catéteres/normas , Dicumarol/normas , Diseño de Equipo/métodos , Diseño de Equipo/normas , Humanos , Cloruro de Polivinilo/normas , Cloruro de Polivinilo/uso terapéutico
13.
Clin Drug Investig ; 39(11): 1021-1030, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31377981

RESUMEN

Successful treatment for respiratory diseases relies on effective delivery of medication to the lungs using an inhalation device. Different inhalers have distinct characteristics affecting drug administration and patient adherence, which can impact clinical outcomes. We report on the development of the Respimat® soft mist inhaler (SMI) and compare key attributes with metered-dose inhalers (MDIs) and dry powder inhalers (DPIs). The Respimat SMI, a pocket-sized device generating a single-breath, inhalable aerosol, was designed to enhance drug delivery to the lungs, reduce the requirements for patient coordination and inspiratory effort, and improve the patients' experience and ease of use. The drug deposition profile with Respimat SMI is favorable compared with MDIs and DPIs, with higher drug deposition to the lung and peripheral airways. The slow velocity and long spray duration of the Respimat SMI aerosol also aid patient coordination. Clinical equivalence has been demonstrated for maintenance treatment of chronic obstructive pulmonary disease using once-daily tiotropium between Respimat SMI (5 µg) and HandiHaler DPI (18 µg). In comparative studies, patients preferred Respimat SMI to MDIs and DPIs; they reported that Respimat SMI was easy to use and felt the inhaled dose was delivered. The Respimat SMI, designed to generate a slow-moving and fine mist, is easy to use and effectively delivers drug treatment to the lungs. The patient-centered design of Respimat SMI improved patient satisfaction, and may help to promote long-term adherence and improve clinical outcomes with asthma and chronic obstructive pulmonary disease.


Asunto(s)
Combinación Albuterol y Ipratropio/administración & dosificación , Broncodilatadores/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Diseño de Equipo/métodos , Inhaladores de Dosis Medida , Administración por Inhalación , Combinación Albuterol y Ipratropio/metabolismo , Asma/tratamiento farmacológico , Asma/metabolismo , Broncodilatadores/metabolismo , Sistemas de Liberación de Medicamentos/instrumentación , Humanos , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/metabolismo
14.
Appl Ergon ; 80: 102-110, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31280793

RESUMEN

This paper discusses the design and evaluation of connected and cooperative vehicle in-vehicle sign designs displayed on a mobile phone: Emergency Electronic Brake Lights (EEBL), Emergency Vehicle Warning (EVW), Traffic Condition Warning, and Road Works Warning. Appropriateness and comprehension of each design alternative were assessed using quantitative (i.e. Likert scales) and qualitative (i.e. open-ended questions) methods. Forty-four participants took part in the study and were shown twelve dashboard camera videos presenting a total of eleven designs alternatives, displayed with or without a legend. Despite their appropriateness, EEBL and EVW signs displayed with a legend were better comprehended and less ambiguous than those displayed without a legend. Moreover, displaying a legend below the signs to warn drivers of an emergency braking ahead was efficient in low visibility condition and could potentially increase safety in critical situations.


Asunto(s)
Conducción de Automóvil/psicología , Urgencias Médicas/psicología , Diseño de Equipo/métodos , Directorios de Señalización y Ubicación , Equipos de Seguridad , Adulto , Automóviles , Comprensión , Simulación por Computador , Femenino , Humanos , Masculino , Tiempo de Reacción , Adulto Joven
15.
Appl Ergon ; 80: 136-145, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31280797

RESUMEN

We compared three passive exoskeleton designs in a mock drilling task under three precision requirements levels, defined by required hole sizes, in terms of physical demands (perceived exertion and muscular activation) and quality. The investigated designs were: 1) an upper-body exoskeleton mainly supporting the shoulder; and both 2) full-body, and 3) upper-body exoskeletons, each with connected supernumerary arms. At a fixed pace, participants (n = 12) repeated "drilling" two same-sized holes for 2 min. A fairly consistent result across exoskeleton designs was that higher precision demands increased some muscle activation levels and deteriorated quality. Designs with supernumerary arms led to the largest reductions in quality and increased physical demands overall, mainly in the low back. The shoulder-focused exoskeleton reduced shoulder demands but appeared to reduce quality with the highest precision requirement. Although future work is needed under more diverse/realistic scenarios, these results might be useful to (re)design occupational exoskeletons.


Asunto(s)
Industria de la Construcción/instrumentación , Diseño de Equipo/métodos , Ergonomía/métodos , Dispositivo Exoesqueleto , Análisis y Desempeño de Tareas , Adulto , Simulación por Computador , Electromiografía , Femenino , Humanos , Masculino , Músculo Esquelético , Enfermedades Musculoesqueléticas/prevención & control , Enfermedades Profesionales/prevención & control , Salud Laboral , Hombro , Adulto Joven
16.
Appl Ergon ; 80: 200-208, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31280806

RESUMEN

Smartphones have become a common tool of daily communication, and a number of text input methods are extensively used. Qwerty and T9 are two universally used smartphone input methods that differ in user experience (UX) when entering phrases with different complexity. Phrase complexity is an indication of the number and type of characters used in a phrase. This study evaluated the impact of both experience and phrase complexity on the UX of Qwerty and T9. Thirty-two participants with different experience levels (high and low) used both Qwerty or T9 to input 40 phrases (both simple and complex phrases). Input time, speed, error rate, galvanic skin response, heart rate, and perceived usability were analyzed as dependent variables. The results indicated that Qwerty was more effective than T9 for entering complex phrases, while no obvious difference was found for simple phrases. Experience had a positive impact on the input method, and Qwerty was more helpful for participants with low experience level. Performance, physiological reaction, and perceived usability data showed similar results. These findings aid the optimal design of text input systems for smartphones.


Asunto(s)
Diseño de Equipo/métodos , Teléfono Inteligente , Envío de Mensajes de Texto , Interfaz Usuario-Computador , Adolescente , Adulto , Femenino , Humanos , Masculino , Percepción , Tiempo de Reacción , Adulto Joven
17.
Appl Ergon ; 80: 43-49, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31280809

RESUMEN

Diabetes can undermine people's ability to drive safely, but most previous studies have focused on its deterioration of the central nervous system. This study sought to investigate how diabetic peripheral neuropathy (DPN), a common complication of diabetes characterized by reduced sensitivity of the limbs, can influence people's braking behavior and other safety-related measures of driving. In addition, it also tested how such a deteriorating effect can be reduced by using certain pedal layout designs. In total, 29 healthy drivers and 31 drivers of type 2 diabetes matched in demographic variables were invited to participate in this study. The participants with type 2 diabetes (they are from here on out referred to as "patients")were then split into two subgroups based on the severity of DPN using the median of the Semmes-Weinstein monofilaments Examination (SWME) scores. All three groups of participants finished a series of vehicle-pedestrian conflict tasks in a driving simulator using nine different types of pedal layouts. These layouts varied in the lateral distance between the accelerator and the brake (45 mm, 60 mm, and 75 mm) and the width of brake pedals (50 mm, 70 mm, 90 mm). The results showed that patients with serious DPN had longer brake reaction times (BRT) and shorter minimum distance-to-collision (DTC) as compared to the other two groups. However, the effects of such a disadvantage varied across different pedal layouts. When the accelerator-brake distance was 45 mm, patients with serious DPN showed no compromised driving performance as compared to other two groups. In conclusion, we found the DPN could undermine driving performance of participants with type 2 diabetes, and a closer accelerator-brake lateral distance (45 mm) may be an optimal choice for them to counteract such a negative influence.


Asunto(s)
Conducción de Automóvil/psicología , Automóviles , Diabetes Mellitus Tipo 2/psicología , Neuropatías Diabéticas/psicología , Diseño de Equipo/métodos , Estudios de Casos y Controles , Diabetes Mellitus Tipo 2/complicaciones , Neuropatías Diabéticas/etiología , Femenino , Pie , Humanos , Masculino , Persona de Mediana Edad , Desempeño Psicomotor , Tiempo de Reacción
18.
Appl Ergon ; 80: 67-74, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31280812

RESUMEN

PURPOSE: To assess differences in spinal, pelvic and lower limb parameters in healthy individuals during a stand-to-sit task using three different seating conditions. METHODS: Ten healthy adults carried out three stand-to-sit movements on different stools: a high ergonomic stool with the seat tilted 10° forward; a standard stool (adjusted to the same height as the ergonomic stool) and a standard stool at a lower level (so their thighs were horizontal). Movements were recorded by an optoelectronic Vicon system. RESULTS: Hip flexion was altered by the height of the seat (significantly greater for the low standard stool in comparison to either the ergonomic stool or the high standard stool (p < 0.0001)). There was also significantly less knee flexion with the ergonomic stool in comparison to the low standard stool (p < 0.0001) and to the high standard stool (p = 0.0017). Lumbar lordosis was not significantly altered by seat height, although it was less pronounced with the ergonomic stool, with a significantly higher range of motion for the pelvis (p = 0.015). At the thoracic level, no differences were observed, except that the stand-to-sit movement on the lower stool produced greater flexion. CONCLUSION: Lumbar lordosis was not increased by the ergonomic stool and the range of lower limb motion was reduced by the high seat. These findings contrast with current opinion that ergonomic seats promote lumbar lordosis.


Asunto(s)
Diseño de Equipo/métodos , Ergonomía , Diseño Interior y Mobiliario , Sedestación , Posición de Pie , Adulto , Fenómenos Biomecánicos , Femenino , Voluntarios Sanos , Humanos , Extremidad Inferior/fisiología , Masculino , Rango del Movimiento Articular , Columna Vertebral/fisiología
19.
Proc Inst Mech Eng H ; 233(10): 963-978, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31311417

RESUMEN

A literature review was conducted to develop more realistic medical simulators that better prepare aspiring health professionals to perform a medical procedure in vivo. Thus, this review proposes an approach that might assist researchers design improved medical simulators, particularly new materials that would enhance the sensation of touch for skin substitutes. By targeting the current needs in the field of simulation learning, we concluded that peripheral venous catheter insertion simulators lack realistic haptic feedback. Enhanced peripheral venous catheter insertion simulators will accelerate the mastery of the medical procedure, thus decreasing the number of failures in patients and costs related to this procedure.


Asunto(s)
Cateterismo Periférico/instrumentación , Diseño de Equipo/métodos , Guías como Asunto , Humanos , Fenómenos Mecánicos , Relaciones Médico-Paciente , Piel
20.
BMJ ; 366: l4230, 2019 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-31266745

RESUMEN

The studyFawsitt C, Thom H, Hunt L. Choice of prosthetic implant combinations in total hip replacement: cost-effectiveness analysis using UK and Swedish hip joint registries data. Value Health 2019;22:303-12.This study was funded by the NIHR Research for Patient Benefit Programme (project number PB-PG-0613-31032).To read the full NIHR Signal, go to https://discover.dc.nihr.ac.uk/content/signal-000771/a-traditional-hip-implant-is-as-effective-as-more-expensive-newer-types-for-older-people.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Diseño de Equipo , Prótesis de Cadera , Complicaciones Posoperatorias , Reoperación , Anciano , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Cadera/instrumentación , Artroplastia de Reemplazo de Cadera/métodos , Cerámica/uso terapéutico , Análisis Costo-Beneficio , Diseño de Equipo/métodos , Diseño de Equipo/normas , Femenino , Prótesis de Cadera/clasificación , Prótesis de Cadera/normas , Humanos , Masculino , Prótesis Articulares de Metal sobre Metal , Osteoartritis de la Cadera/cirugía , Polietileno/uso terapéutico , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Falla de Prótesis/efectos adversos , Reoperación/métodos , Reoperación/estadística & datos numéricos , Reino Unido
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