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1.
Objective: The objective of this study was to conduct a comprehensive analysis of demographics, injury characteristics and hospital resource utilization of significant pediatric electric bicycle (e-bike) injuries leading to hospitalization following an emergency department visit in comparison to pediatric injuries caused by other traffic related mechanisms.

Methods: A retrospective review of all pediatric traffic injury hospitalizations following an emergency department visit to a level I trauma center between October 2014 and September 2016 was conducted. Data regarding age, sex, number of computed tomography (CT) scans obtained, number of major procedures, length of hospital stay (LOS), Injury Severity Score (ISS), and number of injuries per patient were collected and compared between e-bike injuries and other traffic injuries.

Results: Three hundred thirty-seven admissions were analyzed: 46 (14%) were due to e-bike injuries (29% of patients >12 years). Age, proportion of brain injuries, and use of CT were significantly increased compared to mechanical bicycle injuries (13.1?±?3.4 vs. 10.6?±?3.6, 13% vs. 3%, 1 [0–3] vs. 1 [0–1], P < .01, P = .03, P = .05). Age, LOS, and use of CT were significantly increased compared to injuries caused to automobile passengers (13.1?±?3.4 vs. 7.4?±?5.3, 1 [1–3] vs. 1 [1–2], 1 [0–3] vs. 0 [0–1], P < .01, P = .03, P = .01), as well as ISS and number of injuries per patient (P = .04, P < .01). Injuries caused by e-bikes were similar to injuries caused to pedestrians, except for age (13.1?±?3.4 vs. 8.5?±?3.7, P < .01). Multivariable analysis revealed a significant association between mechanism of injury and ISS, with increased ISS among e-bike injuries compared to mecahnical bike injuries (OR 2.56, CI 1.1–5.88, P = 0.03) and automobile injuries (OR 4.16, CI 1.49–12.5, (P < .01).

Conclusion: E-bikes are a significant cause of severe injury in children compared to most other traffic injuries, particularly in older children.  相似文献   

2.
This study aimed to examine the effects of visual display terminal (VDT) viewing angle on human postural angle and muscular activity. The participants’ neck, thoracic bending, and trunk inclination angles; and the activity of sternocleidomastoid, trapezius, splenius capitis, and erector spinae at 5 viewing angles (+40°, +20°,0°, –20°, and –40°) of a VDT screen were collected for 1 min. This study showed that neck and thoracic bending angles increased with viewing angle, while viewing angle did not significantly affect trunk inclination angle. In addition, the activity of trapezius and erector spinae increased when viewing a higher or lower VDT screen height compared with viewing a horizontal VDT screen height; however, the activity of splenius capitis decreased with viewing angle.  相似文献   

3.
Objectives: A cross-sectional study was conducted at the Touro University California campus to compare differences in reaction times and driving performance of younger adult drivers (18–40 years) and older adult drivers (60 years and older). Each test group consisted of 38 participants.

Methods: A Simple Visual Reaction Test (SVRT) tool was used to measure reaction times. The STISIM Drive M100 driving simulator was used to assess driving parameters. Driving performance parameters included mean lane position, standard deviation of mean lane position measured, mean speed, standard deviation of mean speed, car-following delay, car-following modulus, car-following coherence, off-road accidents, collisions, pedestrians hit, and traffic light tickets.

Results: Compared to younger participants, older drivers experienced significantly slower reaction times (510.0 ± 208.8 vs. 372.4 ± 96.1 ms, P =.0004), had more collisions (0.18 ± 0.39 vs. none, P =.0044), drove slower (44.6 ± 6.6 vs. 54.9 ± 11.7 mph, P <.0001), deviated less in speed (12.6 ± 4.3 vs. 16.8 ± 6.3, P =.0011), and were less able to maintain a constant distance behind a pace car (0.42 ± 0.23 vs. 0.59 ± 0.24; P =.0025).

Conclusions: Differences exist in driving patterns of older and younger drivers as measured by reaction times and driving simulator outcomes. These results are the first to compare these 2 specific adult age groups' driving performance as measured by a standardized driving simulator scenario. Identifying these differences is essential in addressing them and preventing future traffic injuries.  相似文献   


4.
The objective was to explore the relationship between person-based variables and work-related variables of presenteeism in four different private sector workplaces. Employees (N=413) filled in a questionnaire related to demographic and socio-economic characteristics, social networks, work-related factors, lifestyle factors and state of health. Presenteeism was assessed using the Stanford Presenteeism Scale 6 (SPS-6). The majority of respondents were male (77.2%), and mean age was 34.7±8.1 years. The prevalence of chronic conditions was 15.9%. The mean score for the SPS-6 was 19.9 (SD, 3.3). The female score was higher than the male score on the SPS-6 in this study. Total score was higher among workers who reported working at high speed. SPS-6 score was higher among individuals with a chronic health problem. Understanding of the workplace and personal factors related to presenteeism may support the health and well-being of workers.  相似文献   

5.
Slips occur as a result of failure of normal locomotion. The purpose of this study is to analyze the impact of alternative footwear (Crocs?, flip-flops) and an industry standard low-top slip-resistant shoe (SRS) under multiple gait trials (normal dry, unexpected slip, alert slip and expected slip) on lower extremity joint kinematics, kinetics and muscle activity. Eighteen healthy male participants (age: 22.28?±?2.2 years; height: 177.66?±?6.9?cm; mass: 79.27?±?7.6?kg) completed the study. Kinematic, kinetic and muscle activity variables were analyzed using a 3(footwear)?×?4(gait trials) repeated-measures analysis of variance at p?=?0.05. Greater plantar flexion angles, lower ground reaction forces and greater muscle activity were seen on slip trials with the alternative footwear. During slip events, SRS closely resembled normal dry biomechanics, suggesting it to be a safer footwear choice compared with alternative footwear.  相似文献   

6.
7.
Objective: The objective of this article is to compare the performance of forward-facing child restraint systems (CRS) mounted on 2 different seats.

Methods: Two different anthropomorphic test device (ATD) sizes (P3 and P6), using the same child restraint system (a non-ISOFIX high-back booster seat), were exposed to the ECE R44 regulatory deceleration pulse in a deceleration sled. Two different seats (seat A, seat B) were used. Three repetitions per ATD and mounting seat were done, resulting in a total of 12 sled crashes. Dummy sensors measured the head tri-axial acceleration and angular rate and the thorax tri-axial acceleration, all acquired at 10,000 Hz. A high-speed video camera recorded the impact at 1,000 frames per second. The 3D kinematics of the head and torso of the ATDs were captured using a high-speed motion capture system (1,000 Hz). A pair-matched statistical analysis compared the outcomes of the tests using the 2 different seats.

Results: Statistically significant differences in the kinematic response of the ATDs associated with the type of seat were observed. The maximum 3 ms peak of the resultant head acceleration was higher on seat A for the P3 dummy (54.5 ± 1.9 g vs. 44.2 ± 0.5 g; P =.012) and for the P6 dummy (56.0 ± 0.8 g vs. 51.7 ± 1.2 g; P =.015). The peak belt force was higher on seat A than on seat B for the P3 dummy (5,488.0 ± 198.0 N vs. 4,160.6 ± 63.6 N; P =.008) and for the P6 dummy (7,014.0 ± 271.0 N vs. 5,719.3 ± 37.4 N; P =.015). The trajectory of the ATD head was different between the 2 seats in the sagittal, transverse, and frontal planes.

Conclusion: The results suggest that the overall response of the booster-seated occupant exposed to the same impact conditions was different depending on the seat used regardless of the size of the ATD. The differences observed in the response of the occupants between the 2 seats can be attributed to the differences in cushion stiffness, seat pan geometry, and belt geometry. However, these results were obtained for 2 particular seat models and a specific CRS and therefore cannot be directly extrapolated to the generality of vehicle seats and CRS.  相似文献   


8.
Objective: We compared the differences in the braking response to vehicle collision between an active human emergency braking (control condition) and cruise control (CC) or adaptive cruise control (ACC).

Methods: In 11 male subjects, age 22 to 67 years, we measured the active emergency braking response during manual driving using the accelerator pedal (control condition) or in condition mimicking CC or ACC. In both conditions, we measured the brake reaction time (BRT), delay to produce the peak braking force (PBD), total emergency braking response (BRT + PBD), and peak braking force (PBF). Electromyograms of leg and thigh muscles were recorded during braking. The tonic vibratory response (TVR), Hoffman reflex (HR), and M-waves were recorded in leg muscles to explore the change in sensorimotor control.

Results: No difference in PBF, TVR amplitude, HR latency, and Hmax/Mmax ratio were found between the control and CC/ACC conditions. On the other hand, BRT and PBD were significantly lengthened in the CC/ACC condition (240 ± 13 ms and 704 ± 70 ms, respectively) compared to control (183 ± 7 ms and 568 ± 36 ms, respectively). BRT increased with the age of participants and the driving experience shortened PBD and increased PBF.

Conclusions: In male subjects, driving in a CC/ACC condition significantly delays the active emergency braking response to vehicle collision. This could result from higher amplitude of leg motion in the CC/ACC condition and/or by the age-related changes in motor control. Car and truck drivers must take account of the significant increase in the braking distance in a CC/ACC condition.  相似文献   


9.
Objective: To conduct near-side moving deformable barrier (MDB) and pole tests with postmortem human subjects (PMHS) in full-scale modern vehicles, document and score injuries, and examine the potential for angled chest loading in these tests to serve as a data set for dummy biofidelity evaluations and computational modeling.

Methods: Two PMHS (outboard left front and rear seat occupants) for MDB and one PMHS (outboard left front seat occupant) for pole tests were used. Both tests used sedan-type vehicles from same manufacturer with side airbags. Pretest x-ray and computed tomography (CT) images were obtained. Three-point belt-restrained surrogates were positioned in respective outboard seats. Accelerometers were secured to T1, T6, and T12 spines; sternum and pelvis; seat tracks; floor; center of gravity; and MDB. Load cells were used on the pole. Biomechanical data were gathered at 20 kHz. Outboard and inboard high-speed cameras were used for kinematics. X-rays and CT images were taken and autopsy was done following the test. The Abbreviated Injury Scale (AIS) 2005 scoring scheme was used to score injuries.

Results: MDB test: male (front seat) and female (rear seat) PMHS occupant demographics: 52 and 57 years, 177 and 166 cm stature, 78 and 65 kg total body mass. Demographics of the PMHS occupant in the pole test: male, 26 years, 179 cm stature, and 84 kg total body mass. Front seat PMHS in MDB test: 6 near-side rib fractures (AIS = 3): 160–265 mm vertically from suprasternal notch and 40–80 mm circumferentially from center of sternum. Left rear seat PMHS responded with multiple bilateral rib fractures: 9 on the near side and 5 on the contralateral side (AIS = 3). One rib fractured twice. On the near and contralateral sides, fractures were 30–210 and 20–105 mm vertically from the suprasternal notch and 90–200 and 55–135 mm circumferentially from the center of sternum. A fracture of the left intertrochanteric crest occurred (AIS = 3). Pole test PMHS had one near-side third rib fracture. Thoracic accelerations of the 2 occupants were different in the MDB test. Though both occupants sustained positive and negative x-accelerations to the sternum, peak magnitudes and relative changes were greater for the rear than the front seat occupant. Magnitudes of the thoracic and sternum accelerations were lower in the pole test.

Conclusions: This is the first study to use PMHS occupants in MDB and pole tests in the same recent model year vehicles with side airbag and head curtain restraints. Injuries to the unilateral thorax for the front seat PMHS in contrast to the bilateral thorax and hip for the rear seat occupant in the MDB test indicate the effects of impact on the seating location and restraint system. Posterolateral locations of fractures to the front seat PMHS are attributed to constrained kinematics of occupant interaction with torso side airbag restraint system. Angled loading to the rear seat occupant from coupled sagittal and coronal accelerations of the sternum representing anterior thorax loading contributed to bilateral fractures. Inward bending initiated by the distal femur complex resulting in adduction of ipsilateral lower extremity resulted in intertrochanteric fracture to the rear seat occupant. These results serve as a data set for evaluating the biofidelity of the WorldSID and federalized side impact dummies and assist in validating human body computational models, which are increasingly used in crashworthiness studies.  相似文献   

10.
Personal cooling garments (PCGs) have gained increased attention in recent years due to heat stress and strain in the working environment. The present study was conducted in hot environments of an iron foundry to evaluate the efficacy of a battery-operated PCG. Twenty-four workers were exposed to climatic conditions of 35.89?±?1.25?°C, 35% relative humidity during 90-min work with PCG and habitual clothing (HC). Mean weighted skin temperature was significantly lower by 4.84?±?1.05?°C compared with HC 0.38?±?1.02?°C (p?p?相似文献   

11.
Purpose: This study collected and analyzed available testing of motor vehicle seat strength in rearward loading by a body block simulating the torso of an occupant. The data were grouped by single recliner, dual recliner, and all belts to seat (ABTS) seats.

Methods: The strength of seats to rearward loading has been evaluated with body block testing from 1964 to 2008. The database of available tests includes 217 single recliner, 65 dual recliner, and 18 ABTS seats. The trends in seat strength were determined by linear regression and differences between seat types were evaluated by Student's t-test. The average peak moment and force supported by the seat was determined by decade of vehicle model year (MY).

Results: Single recliner seats were used in motor vehicles in the 1960s to 1970s. The average strength was 918 ± 224 Nm (n = 26) in the 1960s and 1,069 ± 293 Nm (n = 65) in the 1980s. There has been a gradual increase in strength over time. Dual recliner seats started to phase into vehicles in the late 1980s. By the 2000s, the average strength of single recliner seats increased to 1,501 ± 335 Nm (n = 14) and dual recliner seats to 2,302 ± 699 Nm (n = 26). Dual recliner seats are significantly stronger than single recliner seats for each decade of comparison (P < .001). The average strength of ABTS seats was 4,395 ± 1,185 in-lb for 1989–2004 MY seats (n = 18). ABTS seats are significantly stronger than single or dual recliner seats (P < .001). The trend in ABTS strength is decreasing with time and converging toward that of dual recliner seats.

Conclusions: Body block testing is an quantitative means of evaluating the strength of seats for occupant loading in rear impacts. There has been an increase in conventional seat strength over the past 50 years. By the 2000s, most seats are 1,700–3,400 Nm moment strength. However, the safety of a seat is more complex than its strength and depends on many other factors.  相似文献   


12.
Objectives: The 2 objectives of this study are to (1) examine the rib and sternal fractures sustained by small stature elderly females in simulated frontal crashes and (2) determine how the findings are characterized by prior knowledge and field data.

Methods: A test series was conducted to evaluate the response of 5 elderly (average age 76 years) female postmortem human subjects (PMHS), similar in mass and size to a 5th percentile female, in 30 km/h frontal sled tests. The subjects were restrained on a rigid planar seat by bilateral rigid knee bolsters, pelvic blocks, and a custom force-limited 3-point shoulder and lap belt. Posttest subject injury assessment included identifying rib cage fractures by means of a radiologist read of a posttest computed tomography (CT) and an autopsy. The data from a motion capture camera system were processed to provide chest deflection, defined as the movement of the sternum relative to the spine at the level of T8.

?A complementary field data investigation involved querying the NASS-CDS database over the years 1997–2012. The targeted cases involved belted front seat small female passenger vehicle occupants over 40 years old who were injured in 25 to 35 km/h delta-V frontal crashes (11 to 1 o'clock).

Results: Peak upper shoulder belt tension averaged 1,970 N (SD = 140 N) in the sled tests. For all subjects, the peak x-axis deflection was recorded at the sternum with an average of ?44.5 mm or 25% of chest depth. The thoracic injury severity based on the number and distribution of rib fractures yielded 4 subjects coded as Abbreviated Injury Scale (AIS) 3 (serious) and one as AIS 5 (critical). The NASS-CDS field data investigation of small females identified 205 occupants who met the search criteria. Rib fractures were reported for 2.7% of the female occupants.

Conclusions: The small elderly test subjects sustained a higher number of rib cage fractures than expected in what was intended to be a minimally injurious frontal crash test condition. Neither field studies nor prior laboratory frontal sled tests conducted with 50th percentile male PMHS predicted the injury severity observed. Although this was a limited study, the results justify further exploration of the risk of rib cage injury for small elderly female occupants.  相似文献   

13.
Objectives: This study investigated the relationship between self-reported aberrant driving behaviors, mindfulness, and self-reported crashes and infringements.

Methods: Three hundred and eighteen participants (M = 46.0 years, SD = 13.7 years; female: 81.8%) completed an online survey that assessed aberrant driving behaviors, mindfulness (including regular mindfulness meditation [MM]), and self-reported crashes and infringements during the past 2 years. Structural equation modeling (SEM) was used to examine the relationship between self-reported aberrant driving behaviors and mindfulness simultaneously, as well as with participants' age and estimated kilometers driven over the past year.

Results: The results of the SEM showed that mindfulness was negatively related to each self-reported aberrant driving behavior, with the strongest relationships being between mindfulness and driving-related lapses (?0.58) and errors (?0.46). Participants who practice MM had significantly fewer crashes in the past 2 years and reported significantly fewer driving-related violations and lapses compared to participants who did not practice MM (crashes: 9.3% vs. 18.8%, P < .05; violations: M = 6.66 [SD = 3.44] vs. M = 7.68 [SD = 4.53], P < .05; errors: M = 5.17 [SD = 3.44] vs. M = 6.19 [SD = 4.12], P < .05).

Conclusions: More research is needed to understand whether MM results in more mindful and attentive drivers or whether individuals who practice MM may have other traits or behaviors that are linked to improved safety.  相似文献   

14.
Objective: Driver distraction and inattention are the main causes of accidents. The fact that devices such as navigation displays and media players are part of the distraction problem has led to the formulation of guidelines advocating various means for minimizing the visual distraction from such interfaces. However, although design guidelines and recommendations are followed, certain interface interactions, such as menu browsing, still require off-road visual attention that increases crash risk. In this article, we investigate whether adding sound to an in-vehicle user interface can provide the support necessary to create a significant reduction in glances toward a visual display when browsing menus.

Methods: Two sound concepts were developed and studied; spearcons (time-compressed speech sounds) and earcons (musical sounds). A simulator study was conducted in which 14 participants between the ages of 36 and 59 took part. Participants performed 6 different interface tasks while driving along a highway route. A 3 × 6 within-group factorial design was employed with sound (no sound /earcons/spearcons) and task (6 different task types) as factors. Eye glances and corresponding measures were recorded using a head-mounted eye tracker. Participants’ self-assessed driving performance was also collected after each task with a 10-point scale ranging from 1 = very bad to 10 = very good. Separate analyses of variance (ANOVAs) were conducted for different eye glance measures and self-rated driving performance.

Results: It was found that the added spearcon sounds significantly reduced total glance time as well as number of glances while retaining task time as compared to the baseline (= no sound) condition (total glance time M = 4.15 for spearcons vs. M = 7.56 for baseline, p =.03). The earcon sounds did not result in such distraction-reducing effects. Furthermore, participants ratings of their driving performance were statistically significantly higher in the spearcon conditions compared to the baseline and earcon conditions (M = 7.08 vs. M = 6.05 and M = 5.99 respectively, p =.035 and p =.002).

Conclusions: The spearcon sounds seem to efficiently reduce visual distraction, whereas the earcon sounds did not reduce distraction measures or increase subjective driving performance. An aspect that must be further investigated is how well spearcons and other types of auditory displays are accepted by drivers in general and how they work in real traffic.  相似文献   

15.
Objective: Studies based on accident statistics generally suggest that the presence of a passenger reduces adult drivers' accident risk. However, passengers have been reported to be a source of distraction in a remarkable portion of distraction-related crashes. Although the effect of passengers on driving performance has been studied extensively, few studies have focused on how a child passenger affects the driver.

?A child in a car is a potential distractor for parents, especially for mothers of small children, who often suffer from sleep deficit. The aim of this study was to examine how the presence of child passengers of different ages is associated with a higher driver culpability, which was expected due to child-related distraction and fatigue.

Methods: The analysis was based on the comprehensive data of fatal crashes studied in-depth by multidisciplinary road accident investigation teams in Finland during 1988–2012. Teams determine the primary party who had the most crucial effect on the origin of the event. We define the primary party as culpable and the others involved as nonculpable drivers. The culpability rate was defined as the percentage of culpable drivers and rates were compared for drivers with a child/teen passenger aged 0–17 years (N = 348), with an adult passenger without children (N = 324), and when driving alone (N = 579), grouped by child age and driver gender.

?Drivers with specific risk-related behavior (substantial speeding, driving when intoxicated, unbelted, or without a license) were excluded from the analyses, in order to make the drivers with and without children comparable. Only drivers 26–47 years old were included, representing parents with children 0–9 years of age.

Results: Male drivers were less often culpable with 0- to 17-year-old passengers in the car than alone or with adults. This was not the case with female drivers. The gender difference in culpability was most marked with small children age 0–4 years. Female drivers' culpability rate with a 0- to 4-year-old child passenger was higher and male drivers' culpability rate was lower compared to drivers without passengers or with only adult passengers.

Conclusion: The results indicate that female drivers are at higher risk of crashes than male drivers when driving with small children. Further research is needed to replicate this finding and to determine causal mechanisms.  相似文献   

16.
The negative effects of unemployment on psychological health are well documented, yet Kasl's ( 1982 ) reverse causation hypothesis is that positive psychological health, and in particular self‐esteem, facilitates re‐employment. The aim of this study was to investigate this proposal by assessing levels of self‐esteem, cognitive appraisals and coping efforts among unemployed persons and relating these factors to their employment status six months later. Two hundred and one unemployed (49 per cent female, 51 per cent male; mean age = 32.41 ± 10.18 years) and 128 employed respondents (59 per cent female, 41 per cent male; mean age = 35.0 ± 11.73 years) participated in the study. Participants completed the Adult Self‐Perception Profile, Access to Categories of Experience, Locus of Control, Deakin Coping Scale, and the Meaningful Leisure Activities Questionnaire at baseline and at six‐month follow‐up using a mail‐out survey. Comparison of baseline appraisals revealed that future re‐employed participants rated their latent deprivation lower and their internal locus of control higher than those continuously unemployed, and they also derived more internal meaning from leisure activities. Overall, the results provide support for Kasl's reverse causation hypothesis extended to these other domains of psychological health. Intervention strategies designed to incorporate the promotion of these factors are discussed. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

17.
Objective. Cognitive failure is one of the factors which can be influenced by personal and professional characteristics. This research was carried out to study the effect of work-related quality of life (WRQoL) and some related factors on cognitive failures (CF) among nurses. Methods. This cross-sectional study was conducted among nurses working in intensive care units, critical care units and emergency units in 2014. Results. In total, 750 nurses participated in the study. The mean?±?SD for the total CF and WRQoL was 40.5?±?12.7 and 75.8?±?13.7 respectively. The results show that CF have a statistically significant difference among the age groups, experience groups and working units. Multiple regression tests show that age, income and WRQoL have a significant effect on CF. Based on the results, for a unit increase in WRQoL we expect a 0.26 unit decrease in CF. Analysis of variance results show that the emergency ward had changed the overall effect of WRQoL on CF, after the effect of WRQoL was controlled. Conclusions. Overall results from the present research indicated that, despite the high level of WRQoL among the studied nurses, the rate of CF was not at an appropriate level. Development of supportive and interventional strategies is highly recommended.  相似文献   

18.
Exposure to methyl methacrylate (MMA), total dust and health symptoms were investigated in 20 dental laboratories located in Tehran, Iran. Time-weighted average (TWA) of MMA and peak concentrations were determined, using XAD-2 tubes followed by GC-ID analysis. Total dusts were evaluated gravimetrically. Health symptoms were asked using a questionnaire. TWA for technicians with direct and indirect exposure to MMA were 327.28 ± 79.42 and 282.9 ± 41.84 mg/m3 , respectively. Peak concentration of MMA for those technicians were 337.0 ± 36.81 and 328.88 ± 45.40 mg/m3, respectively.

There were no significant differences between TWA of MMA and peak concentration in different weekly workdays; however, within-day variations were observed (P < .05).

TWA of MMA and peak concentration correlation with the laboratory volume were 0.61-0.65. Dust exposure of technicians was 2.35 ± 2.70 mg/m3. Cough and skin dryness were the common health symptoms. Smoking and asbestos exposure history were factors influencing cough prevalence (p < .05).

It is concluded that the current Short-Term Exposure Limit (STEL) is not low enough to protect technicians against the adverse effects caused by MMA.  相似文献   

19.
In this study the anisotropic characteristics of TFT-LCD (Thin-Film-Transistor- Liquid Crystal Display) screens were examined. Anisotropy occurs as the distribution of luminance and contrast changes over the screen surface due to different viewing angles. On the basis of detailed photometric measurements the detection performance in a visual reaction task was measured in different viewing conditions. Viewing angle (0°, frontal view; 30°, off-axis; 50°, off-axis) as well as ambient lighting (a dark or illuminated room) were varied. Reaction times and accuracy of detection performance were recorded. Results showed TFT’s anisotropy to be a crucial factor deteriorating performance. With an increasing viewing angle performance decreased. It is concluded that TFT’s anisotropy is a limiting factor for overall suitability and usefulness of this new display technology.  相似文献   

20.
BackgroundBackground: Pallets are key components of domestic supply chains, and yet present unique hazards when used by homeowners and retailers for unintended uses. No previous works have investigated non-occupational injuries that occur due to unintentional contact with pallets. This study sought to describe the incidence and epidemiology of non-occupational pallet-related injuries as seen in United States emergency departments (EDs). Method: The National Electronic Injury Surveillance System database was used to derive national, weighted estimates of pallet-related injuries by age, sex, injured body part, and location where injury occurred. Data for the years 2014 to 2018 were analyzed with all relevant narratives reviewed. Results: From 2014 to 2018, there were an estimated 30,493 persons who visited an ED for a pallet-related injury. The yearly incidence of pallet injuries rose during this period. The 35–44 age group (n = 5,481) was most likely to be injured, but about 3,000 children and youth under 18 years of age were injured and more than 4,000 persons 65 years of age or older suffered injuries. The elderly were especially likely to suffer injuries from slip, trip and fall incidents. The lower extremities were the most commonly injured body parts. An estimated 3,964 persons, accounting for approximately 14% of all pallet-related injuries, were treated for injuries incurred while at a retail establishment. African Americans, Hispanics, and the elderly appeared to be disproportionately more likely to have pallet-related injuries in retail locations. Conclusions: Non-occupational pallet-related injuries affect a wide range of patients and cause a variety of injuries, with the elderly being especially vulnerable to tripping incidents. Retailer prevention strategies should focus on the misuse of pallets for merchandising purposes. Industry should maintain control of pallets so they are not used for unintended purposes. Practical applications: Retailers should limit the use of pallets for floor-level merchandising purposes and remove pallets from customer-facing locations where unintentional contact could occur. Owners of pallets should maintain them in a controlled supply chain so that they don’t leak out into the hands of homeowners. Policy-makers should educate the public about the dangers of used pallets.  相似文献   

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