Characterization and calibration of multiple 2D laser scanners

This paper presents the comparative evaluation of multiple compact and lightweight 2D laser scanners for their possible backpack based scanning and mapping applications. These scanners include Hokuyo URG-04LX, Slamtec RPLidar A1-M8 and Hokuyo UTM- 30LX-EW scanners. Since the technical datasheets provide general information and limited working details, this research presents a thorough study on the performance of each scanner related explicitly to indoor mapping operations. A series of scanning experiments have been performed for the characterization of each scanner using statistical analysis. During the testing, all the scanning data has been recorded using Robot Operating System (ROS) and then computed in offline processing. In initial tests, each scanner's drift effect on range measurements has been tested and presented in the relevant section of the paper. In continuation, the effect of various scanning distances on measurement accuracy has been evaluated and discussed. Later the impact of various materials typically found in indoor vicinities and their respective properties of color and smoothness have been tested and provided in the paper. Finally, a Kalman Filtering based mathematical formulation has been utilized to calibrate each scanner and to reduce the measuring uncertainties as observed in various tests for each scanner

Causes and incidence of community-acquired serious infections among young children in south Asia (ANISA): an observational cohort study.

BACKGROUND: More than 500 000 neonatal deaths per year result from possible serious bacterial infections (pSBIs), but the causes are largely unknown. We investigated the incidence of community-acquired infections caused by specific organisms among neonates in south Asia. METHODS: From 2011 to 2014, we identified babies through population-based pregnancy surveillance at five sites in Bangladesh, India, and Pakistan. Babies were visited at home by community health workers up to ten times from age 0 to 59 days. Illness meeting the WHO definition of pSBI and randomly selected healthy babies were referred to study physicians. The primary objective was to estimate proportions of specific infectious causes by blood culture and Custom TaqMan Array Cards molecular assay (Thermo Fisher, Bartlesville, OK, USA) of blood and respiratory samples. FINDINGS: 6022 pSBI episodes were identified among 63 114 babies (95·4 per 1000 livebirths). Causes were attributed in 28% of episodes (16% bacterial and 12% viral). Mean incidence of bacterial infections was 13·2 (95% credible interval [CrI] 11·2-15·6) per 1000 livebirths and of viral infections was 10·1 (9·4-11·6) per 1000 livebirths. The leading pathogen was respiratory syncytial virus (5·4, 95% CrI 4·8-6·3 episodes per 1000 livebirths), followed by Ureaplasma spp (2·4, 1·6-3·2 episodes per 1000 livebirths). Among babies who died, causes were attributed to 46% of pSBI episodes, among which 92% were bacterial. 85 (83%) of 102 blood culture isolates were susceptible to penicillin, ampicillin, gentamicin, or a combination of these drugs. INTERPRETATION: Non-attribution of a cause in a high proportion of patients suggests that a substantial proportion of pSBI episodes might not have been due to infection. The predominance of bacterial causes among babies who died, however, indicates that appropriate prevention measures and management could substantially affect neonatal mortality. Susceptibility of bacterial isolates to first-line antibiotics emphasises the need for prudent and limited use of newer-generation antibiotics. Furthermore, the predominance of atypical bacteria we found and high incidence of respiratory syncytial virus indicated that changes in management strategies for treatment and prevention are needed. Given the burden of disease, prevention of respiratory syncytial virus would have a notable effect on the overall health system and achievement of Sustainable Development Goal. FUNDING: Bill & Melinda Gates Foundation

A Comparative Study of Multiple 2D Laser Scanners for Outdoor Measurements

This research work examines the performance of several compact and lightweight 2D laser scanners, including the Hokuyo URG-04LX, RP Lidar and Hokuyo UTM-30LX-EW, for their potential use in scanning and mapping applications. A detailed study was conducted to evaluate the performance of each scanner specifically for outdoor mapping operations. Multiple experiments were performed to characterize each scanner through statistical analysis. The paper discusses the results of testing for the drift effect, the impact of direct sun exposure to different materials and the effect of range measurement in outdoor environments on range and measurement accuracy

Effectiveness of community case management of severe pneumonia with oral amoxicillin in children aged 2-59 months in Matiari district, rural Pakistan: a cluster-randomised controlled trial

Background:Pneumonia is a leading global cause of morbidity and mortality in children younger than 5 years. In Pakistan, the proportion of deaths due to pneumonia is higher in rural areas than it is in urban areas, with a substantial proportion of individuals dying at home because referral for care is problematic in such areas. We aimed to establish whether community case identification and management of severe pneumonia by oral antibiotics delivered through community health workers has the potential to reduce the number of infants dying at home. Methods: We did a cluster-randomised controlled trial in Matiari district of rural Sindh, Pakistan. Public-sector lady health workers (LHWs) undertook community case management of WHO-defined severe pneumonia. The children in intervention clusters with suspected pneumonia were screened by LHWs and those diagnosed with severe pneumonia were prescribed oral amoxicillin syrup (90 mg/kg per day in two doses) for 5 days at home. Children in control clusters were given one dose of oral co-trimoxazole and were referred to their nearest health facility for admission and intravenous antibiotics, as per government policy. In both groups, follow-up visits at home were done at days 2, 3, 6, and 14 by LHW. The primary outcome was treatment failure by day 6 after enrolment. We matched and randomly allocated 18 clusters (union councils, the smallest administrative unit of the district) to either intervention and control using a computer-generated randomisation scheme. Analyses were done per-protocol. This trial is registered with ClinicalTrials.gov, number NCT01192789. Findings: 2341 children in intervention clusters and 2069 children in control clusters participated in the study, enrolled between Feb 13, 2008, and March 15, 2010. We recorded 187 (8%) treatment failures by day 6 in the intervention group and 273 (13%) in the control group. After adjusting for clustering, the risk difference for treatment failure was -5.2% (95% CI -13.7% to 3.3%). We recorded three deaths, two by day 6 and one between days 7 and 14. We recorded no serious adverse events. Interpretation: Public sector LHWs in Pakistan were able to satisfactorily diagnose and treat severe pneumonia at home in rural Pakistan. This strategy might effectively reach children with pneumonia in settings where referral is difficult, and it could be a key component of community detection and management strategies for childhood pneumonia