This study explores the feasibility of applying ragdoll physics, a procedural animation, and related game-engine technologies to create real-time simulations for investigating crowd disasters.

We harnessed the power of the Unity Game Engine to develop real-time simulation for the dynamics of a crowd disaster with rendering of scene objects and user interface (UI) elements. Humanoid agents with trigger colliders were linked to color schemes representing impact forces sustained with lethal thresholds ranging from 500 to 550 pounds force for males and 450 to 500 pounds force for females. The simulation enables users to manipulate parameters such as population, crowd density, directional movement and forces applied.

Our simulation showcases an animated real-time depiction of a crowd disaster and enables visualization of casualties, both injured and dead, based upon a quantitative evaluation of the forces sustained.

Utilization of the Unity Game Engine for the development of visually-engaging real-time crowd disaster simulation has promising outcomes. This novel approach for modeling and analysis of crowd dynamics may provide valuable insights with applications in mass gatherings, crowd management, safety, and preparedness.

Individuals who self-harm have increased suicide rates. Brief interventions are associated with reduced repeated suicide attempts. However, very few previous studies investigated the acceptability of brief interventions before implementing new trials.

We aimed to explore the perceptions of individuals who self-harm toward a brief intervention, the Chinese version of the volitional help sheet (VHS-C), which encourages people to link a critical situation with an appropriate response.

Fourteen participants who presented to hospitals with self-harm were interviewed about their perspectives regarding the acceptability of the paper- and web-based VHS-C. Data were analysed with the framework method.

The participants could understand the intended goal of the VHS-C by reading the written instructions, but indicated that having verbal instructions would also help. They shared the reasons why they felt the VHS-C was helpful (e.g. relatable contents, useful coping strategies and appropriate instructions that made them feel understood) or unhelpful (e.g., being not specific enough, not useful during the crisis and triggering negative emotional responses). Some indicated that the VHS-C might not be applicable to people experiencing ongoing distress in emergency departments. Most participants preferred the web-based to the paper-based VHS-C, and suggested that the format and frequency of follow-up reminders could leave the patient to decide.

The contents of the VHS-C were acceptable for people who presented to hospitals with self-harm. The VHS-C may be more helpful before individuals encounter suicidal thoughts than when they have an ongoing crisis.

Attention-deficit hyperactivity disorder (ADHD) increases the risk of suicidal behaviours through psychiatric comorbidities; however, a significant direct association has not been observed between ADHD and suicide attempts.

To evaluate the risk of suicide attempt in adolescents and young adults with ADHD.

Using a nationwide, population-based insurance claims database, this longitudinal cohort study enrolled 20 574 adolescents and young adults with ADHD and 61 722 age- and gender-matched controls between 2001 and 2009. Any suicide attempt was identified from enrolment to 31 December 2011. The association between ADHD medications and the likelihood of suicide attempt was assessed.

ADHD was an independent risk factor for any suicide attempt (hazard ratio = 3.84, 95% CI = 3.19–4.62) and repeated suicide attempts (hazard ratio = 6.52, 95% CI = 4.46–9.53). Subgroup analyses of men, women, adolescents and young adults demonstrated the same trend. Methylphenidate or atomoxetine treatment did not increase the risk of suicide attempt or repeated suicide attempts. Long-term methylphenidate treatment was associated with a significantly decreased risk of repeated suicide attempts in men (hazard ratio = 0.46, 95% CI = 0.22–0.97).

ADHD was a risk factor for suicide attempt and a stronger predictor of repeated suicide attempts, independent of comorbidities. Further investigation is warranted to explore the mechanism underlying the association between ADHD and suicidal behaviours.

None.

To rapidly establish a temporary isolation ward to handle an unexpected sudden outbreak of severe acute respiratory syndrome (SARS) and to evaluate the implementation of exposure control measures by healthcare workers (HCWs) for SARS patients.

Rapid creation of 60 relatively negative pressure isolation rooms for 196 suspected SARS patients transferred from 19 hospitals and daily temperature recordings of 180 volunteer HCWs from 6 medical centers.

A military hospital.

Of the 196 patients, 34 (17.3%) met the World Health Organization criteria for probable SARS with positive results of serologic testing for SARS-associated coronavirus (SARS-CoV), reverse transcriptase polymerase chain reaction (RT-PCR) from nasopharyngeal or throat swabs for SARS-CoV, or both. Seventy-four patients had suspected SARS based on unprotected exposure to SARS patients; three of them had positive results on RT-PCR but negative serologic results. The remaining 88 patients did not meet the criteria for a probable or suspected SARS diagnosis. Of the 34 patients with probable SARS, 13 were transferred to medical centers to receive mechanical ventilation due to rapid deterioration of chest x-ray results, and three patients died of SARS despite intensive therapy in medical centers. During the study period, one nurse developed probable SARS due to violation of infection control measures, but there was no evidence of cross-transmission to other HCWs.

Despite the use of full personal protection equipment, the facility failed to totally prevent exposures of HCWs to SARS but minimized the risk of nosocomial transmission. Better training and improvements in infection control infrastructure may limit the impact of SARS.