SciCombinator

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Concept: Door

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This paper presents an innovative access control system, based on human detection and path analysis, to reduce false automatic door system actions while increasing the added values for security applications. The proposed system can first identify a person from the scene, and track his trajectory to predict his intention for accessing the entrance, and finally activate the door accordingly. The experimental results show that the proposed system has the advantages of high precision, safety, reliability, and can be responsive to demands, while preserving the benefits of being low cost and high added value.

Concepts: Scientific method, Value added, Access control, Physical security, Door, Door security, Safe, Security companies

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Independent mobility is vital to individuals of all ages, and wheelchairs have proven to be great personal mobility devices. The tasks of opening and navigating through a door are trivial for healthy people, while the same tasks could be difficult for some wheelchair users. A wide range of intelligent wheelchair controllers and systems, robotic arms, or manipulator attachments integrated with wheelchairs have been developed for various applications, including manipulating door knobs. Unfortunately, the intelligent wheelchairs and robotic attachments are not widely available as commercial products. Therefore, the current manuscript presents the modeling and simulation of a novel but simple technology in the form of a passive wheelchair accessory (straight, arm-like with a single wheel, and arc-shaped with multiple wheels) for pushing doors open from a wheelchair. From the simulations using different wheel shapes and sizes, it was found that the arc-shaped accessory could push open the doors faster and with almost half the required force as compared to the arm-like accessory. Also, smaller spherical wheels were found to be best in terms of reaction forces on the wheels. Prototypes based on the arc-shaped accessory design will be manufactured and evaluated for pushing doors open and dodging or gliding other obstacles.

Concepts: Force, Wheelchair, Mobility device, The Doors, Door

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The development of long-term event memory in preverbal infants remains elusive. To address this issue, we applied an eye-tracking method that successfully revealed in great apes that they have long-term memory of single events. Six-, 12-, 18- and 24-month-old infants watched a video story in which an aggressive ape-looking character came out from one of two identical doors. While viewing the same video again 24 hours later, 18- and 24-month-old infants anticipatorily looked at the door where the character would show up before it actually came out, but 6- and 12-month-old infants did not. Next, 12-, 18- and 24-month-old infants watched a different video story, in which a human grabbed one of two objects to hit back at the character. In their second viewing after a 24-hour delay, 18- and 24-month-old infants increased viewing time on the objects before the character grabbed one. In this viewing, 24-month-old infants preferentially looked at the object that the human had used, but 18-month-old infants did not show such preference. Our results show that infants at 18 months of age have developed long-term event memory, an ability to encode and retrieve a one-time event and this ability is elaborated thereafter.

Concepts: Human, Hominidae, Chimpanzee, Gorilla, Ape, Object, The Doors, Door

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Survival from pediatric cardiac arrest due to trauma has been reported to be 0.0%-8.8%. Some argue that resuscitation efforts in the case of trauma-related cardiac arrests are futile. We describe a successful outcome in the case of a child who suffered cardiac arrest caused by external traumatic airway obstruction. Our case illustrates how to deal with pediatric traumatic cardiac arrests in an out-of-hospital environment. It also illustrates how good clinical treatment in these situations may be supported by correct treatment after hospital admission when it is impossible to ventilate the patient to provide sufficient oxygen delivery to vital organs. This case relates to a lifeless child of 3-5 years, blue, and trapped by an electrically operated garage door. The first ambulance arrived to find several men trying to bend the frame and the door apart in order to extricate the child, who was hanging in the air with head and neck squeezed between the horizontally-moving garage door and the vertical door frame. One paramedic found a car jack and used it to push the door and the frame apart, allowing the lifeless child to be extricated. Basic life support was then initiated. Intubation was performed by the anesthesiologist without drugs. With FiO2 1.0 the first documented SaO2 was <50%. Restoration of Spontaneous Circulation was achieved after thirty minutes, and she was transported to the hospital. After a few hours she was put on venous-arterial ECMO for 5.5 days and discharged home after two months. Outpatient examinations during the rest of 2013 were positive, and the child found not to be suffering from any injuries, either physical or mental. The last follow-up in October 2014 demonstrated she had made a 100% recovery and she started school in August 2014.

Concepts: Medicine, Heart, Cardiac arrest, Organ, English-language films, Emergency medical services, Organs, Door

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Due to continuing modernisation, the number of automatic doors in routine use, including powered revolving doors, has increased in recent years. Automatic revolving doors are found mostly in department stores, airports, railway stations and hospitals. Although safety arrangements and guidelines concerning the installation of automatic doors are in existence, their disregard in conjunction with obsolete or incorrect installation can lead to fatal accidents. In this report, a 19-month-old boy is described whose right arm was caught between the elements of an automatic revolving door. As a direct result of rescue attempts, the child’s body was drawn further into the narrow gap between elements of the door. To get the boy’s body out of the 4-cm-wide gap between the fixed outer wall of the revolving door and the revolving inner, back-up batteries had to be disconnected so as to stop the electrical motor powering the door. Cardiopulmonary resuscitation was begun immediately after the rescue but was unsuccessful; the child was declared dead at the hospital he was taken to. The cause of death was a combination of compression-related skull and brain injury together with thoracic compression. This case shows an outstanding example of the preventive aspect as a special task of forensic medicine. Additionally, it serves as a warning for the correct installation and use of automatic revolving doors. Even so, small children should not use these doors on their own, but only with an alert companion, so as to prevent further fatal accidents of this sort.

Concepts: Death, Cardiopulmonary resuscitation, Artificial respiration, Revolving door, Door, Doors

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The use of hospital isolation rooms has increased considerably in recent years due to the worldwide outbreaks of various emerging infectious diseases. However, the passage of staff through isolation room doors is suspected to be a cause of containment failure, especially in case of hinged doors. It is therefore important to minimize inadvertent contaminant airflow leakage across the doorway during such movements. To this end, it is essential to investigate the behavior of such airflows, especially the overall volume of air that can potentially leak across the doorway during door-opening and human passage. Experimental measurements using full-scale mock-ups are expensive and labour intensive. A useful alternative approach is the application of Computational Fluid Dynamics (CFD) modelling using a time-resolved Large Eddy Simulation (LES) method. In this study simulated air flow patterns are qualitatively compared with experimental ones, and the simulated total volume of air that escapes is compared with the experimentally measured volume. It is shown that the LES method is able to reproduce, at room scale, the complex transient airflows generated during door-opening/closing motions and the passage of a human figure through the doorway between two rooms. This was a basic test case that was performed in an isothermal environment without ventilation. However, the advantage of the CFD approach is that the addition of ventilation airflows and a temperature difference between the rooms is, in principle, a relatively simple task. A standard method to observe flow structures is dosing smoke into the flow. In this paper we introduce graphical methods to simulate smoke experiments by LES, making it very easy to compare the CFD simulation to the experiments. The results demonstrate that the transient CFD simulation is a promising tool to compare different isolation room scenarios without the need to construct full-scale experimental models. The CFD model is able to reproduce the complex airflows and estimate the volume of air escaping as a function of time. In this test, the calculated migrated air volume in the CFD model differed by 20% from the experimental tracer gas measurements. In the case containing only a hinged door operation, without passage, the difference was only 10%.

Concepts: Fluid dynamics, Experiment, Simulation, Operations research, Test method, Computational fluid dynamics, Escape, Door

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Freezing of gait (FOG) is a disabling form of gait disturbance that is common in the advanced stages of Parkinson’s disease (PD). Despite its prevalence, methods of studying and assessing FOG are limited. We have previously shown that a virtual reality paradigm was able to distinguish between those who report FOG (“freezers”) and those who do not report FOG (“non-freezers”). In this paradigm, ‘freezers’ were found to have prolonged footstep latency in response to known triggers of FOG including doorways, sliding doors and dual-tasking. In this study, we employed the same paradigm to assess performance of 27 freezers and 14 non-freezers in their clinical ‘on’ and ‘off’ medication states. In this study, only participants in the freezing group demonstrated statistically significant increases in latencies experienced in the ‘off’ state compared to the ‘on’ state in response to wide and narrow doorways and the opening of a sliding door. By contrast, these behavioral differences were not apparent in non-freezers. Furthermore the delay was specific to environmental cues and was not due to generalized slowing in the ‘off’ state. The findings suggest that this motor delay when processing environmentally salient cues is specific to freezers and is partially mediated by dopamine-dependent neurocircuitry.

Concepts: Parkinson's disease, Basal ganglia, Substantia nigra, Neurotransmitter, Dopamine, Virtual reality, The Doors, Door

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A case series of five patients with multi-level cervical myelopathy(MCM) treated by French-door cervical laminoplasty(FDCL) and use of unicortical iliac crest graft as spacer fixed with titanium mini-plates and screws is described.

Concepts: Iliac crest, Door

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The major pathways for transport of pyrethroids were determined in runoff studies conducted at a full scale test facility in central California. The six replicate house lots were typical of front lawns and house fronts of California residential developments and consisted of stucco walls, garage doors, driveways, and residential lawn irrigation sprinkler systems. Each of the six lots also included a rainfall simulator to generate artificial rainfall events. Different pyrethroids were applied to five surfaces-driveway, garage door and adjacent walls, lawn, lawn perimeter (grass near the house walls), and house walls above grass. The volume of runoff water from each house lot was measured, sampled, and analyzed to determine the amount of pyrethroid mass lost from each surface. Applications to three of the house lots were made using the application practices typically used prior to recent label changes, while applications were made to the other three house lots according to the revised application procedures. Results from the house lots using the historic application procedures showed that losses of the compounds applied to the driveway and garage door (including the adjacent walls) were 99.75 percent of total measured runoff losses. The highest losses were associated with significant rainfall events rather than lawn irrigation events. However, runoff losses were 40 times less using the revised application procedures recently specified on pyrethroid labels. Environ Toxicol Chem © 2013 SETAC.

Concepts: Agriculture, Water, Irrigation, Lawn, Irrigation sprinkler, Door, Garage, Driveway

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The main objective of this study was to determine how manipulating the amount of sensory information available about the body and surrounding environment influenced freezing of gait (FOG), while walking through a doorway. It was hypothesized that the more limited the sensory information, the greater the occurrence of freezing of gait. Nineteen patients with Parkinsoǹs disease who experience freezing of gait (PD-FOG) walked through a doorway or into open space in complete darkness. The three doorway conditions included: (i) FRAME (DARK) - walking through the remembered door frame; (ii) FRAME - walking through the door with the door frame illuminated; (iii) FRAME+BODY - walking through the door (both the door and the limbs illuminated). Additionally, two conditions of walking away from the doorway included: (iv) NO FRAME (DARK) - walking into open space; (v) NO FRAME+BODY - walking into open space with the limbs illuminated, to evaluate whether perception (or fear) of the doorway might account for FOG behaviour. Key outcome measures included: the number of freezing of gait episodes recorded, total duration of freezing of gait, and the percentage of time spent frozen. Significantly more freezing of gait episodes occurred when participants walked toward the doorway in complete darkness compared to walking into open space (p<0.05). Similar to previous studies, velocity (p<0.001) and step length (p<0.0001) significantly decreased when walking through the door in complete darkness, compared to all other conditions. Significant increases in step width variability were also identified but only when walking into open space (p<0.005). These results support the notion that sensory deficits may have a profound impact on freezing of gait that need to be carefully considered.

Concepts: Parkinson's disease, Walking, Locomotion, Darkness, Door