Self-Reconfigurable Hierarchical Frameworks for Formation Control of Robot Swarms.

Hierarchical frameworks-a special class of directed frameworks with a layer-by-layer architecture-can be an effective mechanism to coordinate robot swarms. Their effectiveness was recently demonstrated by the mergeable nervous systems paradigm (Mathews et al., 2017), in which a robot swarm can switch dynamically between distributed and centralized control depending on the task, using self-organized hierarchical frameworks. New theoretical foundations are required to use this paradigm for formation control of large swarms. In particular, the systematic and mathematically analyzable organization and reorganization of hierarchical frameworks in a robot swarm is still an open problem. Although methods for framework construction and formation maintenance via rigidity theory exist in the literature, they do not address cases of hierarchy in a robot swarm. In this article, we extend bearing rigidity to directed topologies and extend the Henneberg constructions to generate self-organized hierarchical frameworks with bearing rigidity. We investigate three-key self-reconfiguration problems: 1) framework merging; 2) robot departure; and 3) framework splitting. We also derive the mathematical conditions of these problems and then develop algorithms that preserve rigidity and hierarchy using only local information. Our approach can be used for formation control generally, as in principle it can be coupled with any control law that makes use of bearing rigidity. To demonstrate and validate our proposed hierarchical frameworks and methods, we apply them to four scenarios of reactive formation control using an example control law.

Characteristics and outcomes of critically ill children transported by ambulance in a Turkish prehospital system: a multicenter prospective cohort study.

BACKGROUND: The most underdeveloped area in the care of critically-ill-children (CIC) is the prehospital period. Appropriate prehospital assessment and life-saving-interventions (LSI) of this population are challenging and require dedicated resources to ensure the best outcomes. We aimed to determine the characteristics and outcomes of CIC transported to the Turkish Pediatric Emergency Departments (EDs). The frequency and distribution of LSI administered by prehospital providers on route and in the EDs were also investigated. METHODS: This prospective study was conducted at 4 metropolitan cities and 9 tertiary pediatric EDs between August 2014-August 2015. A survey based study evaluated all CIC who were brought by ambulance to the participant EDs. CIC were defined as a patient who requires LSI or needs intensive care admission for any reason. Patient demographics, clinical features, reason for transport, performed procedures in the ambulance or ED were sought. Finally, the short-term outcomes of transported CIC and transport-associated risks were analyzed. RESULTS: During the study period, a total 2094 children were brought by ambulance to all participant EDs. Only 227 (10.8%) of them were critically-ill. Emergency Medical Services (EMS) providers were less likely to perform procedures in CIC if they were staffed with paramedics (p < 0.001). Most procedures were performed on children aged one or older (p < 0.001). No procedure was performed in the ambulance for nearly one fourth of patients who received LSI in the EDs. If the EMS did not have a physician, prehospital providers were less likely to provide immediate LSIs (p < 0.001). CIC were more likely referred from secondary/tertiary care hospitals. The short-term mortality rate was higher if the ambulance was staffed by only paramedics. CONCLUSION: This study demonstrated that Turkish prehospital pediatric emergency care is deficient. We offer a clinical overview of pediatric emergencies to aid EMS directors, policymakers, and ED directors in planning the care of CIC.

How Important Are Parental Age and Educational Level in Nonurgent Admissions to the Pediatric Emergency Department?

OBJECTIVE: The aims of the present study were to investigate the reasons parents prefer the pediatric emergency department for nonurgent admissions and to evaluate the effect of parental age and educational level on nonurgent admissions and the relationship between the reasons for nonurgent admissions and child age. METHODS: We conducted a cross-sectional survey at an emergency department of a tertiary care pediatric referral center. A questionnaire that was prepared to understand the reasons underlying nonurgent admissions was administered to the parents of 1033 children who were classified as nonurgent cases using the Pediatric Canadian Triage and Acuity Scale (4-5). RESULTS: The most common reasons for nonurgent admissions were the concern for progression in child's complaints, the complaints with an onset outside working hours, and the parental perception that more cautious and better care is provided in the emergency department. The most urgent complaints from the parental perspective included fever (23.1%), vomiting (11.0%), and diarrhea (10.5%), respectively. The mean age of the mothers was 31.1 ± 5.9 years (17-51 years), and the mean age of the fathers was 34.94 ± 6.1 years (20-60 years). Parents younger than 30 years were more likely to prefer the emergency department due to convenience and economic reasons. Nonurgent admissions due to confidence in the emergency department were more frequent among parents who were primary school graduate. CONCLUSIONS: It is critically important to examine why parents prefer the emergency department for nonurgent conditions of their children and to develop solution offers in this regard. The improvements to be made in the emergency department would both prioritize patients requiring urgent care and increase the productivity of emergency department staff.

Outcome of out-of-hospital cardiopulmonary arrest in children: A multicenter cohort study.

Kurt F, Kendirli T, Gündüz RC, Kesici S, Akça H, Sahin S, Kalkan G, Derbent M, Tuygun N, Ödek Ç, Gültekin-Keser A, Oguz S, Polat E, Derinöz O, Tekin D, Teksam Ö, Bayrakci B, Suskan E. Outcome of out-of-hospital cardiopulmonary arrest in children: A multicenter cohort study. Turk J Pediatr 2018; 60: 488-496. The aim of this study was to evaluate the demographic characteristics of children who experienced out-of-hospital cardiopulmonary arrest (CPA), and to assess the impact of the bystander cardiopulmonary resuscitation (CPR) on the survival rate of witnessed arrests and the effects of the arrest and CPR durations on the neurological outcomes. This multicenter, retrospective study included a total of 182 patients who underwent CPR for out-of-hospital CPA between January 2008 and December 2012 at six centers in Ankara, Turkey. The median [interquartile range (IQR)] age was 22 (5-54) months; 60.4% of the patients were males, and 44% were younger than one year of age. The witnessed arrest rate was 75.8% (138/182) and the rate of bystander CPR was 13.9% (13/93). In these patients the rate of the return of spontaneous circulation (ROSC) was higher (76.9%). Following resuscitation in the patients for whom the spontaneous circulation was able to be returned, the median (IQR) duration of arrest was 5 (1- 15) min, while it was 15 (5-40) min for the remaining patients (p < 0.001). The ROSC rate was 94.9% in patients who underwent CPR for less than 20 min and 22% in patients requiring CPR longer than 20 min (p < 0.001). Survival to hospital discharge was 14.3%. Of these patients, 57.7% experienced neurological disability. The short duration of an arrest and the presence of CPR are both critical for survival. We suggest that a witness to the CPA, performing early and efficient CPR, yields better results.