Mathematical modelling of container transfers for a fleet of autonomous straddle carriers

The main contribution of this paper is a mathematical model describing performance metrics for coordinating multiple mobile robots in a seaport container terminal. The scenario described here requires dealing with many difficult practical challenges such as the presence of multiple levels of container stacking and sequencing, variable container orientations, and vehicular dynamics that require finite acceleration and deceleration times. Furthermore, in contrast to the automatically guided vehicle planning problem in a manufacturing environment, the container carriers described here are free ranging. Although, the port structure imposes a set of "virtual" roadways along which the vehicles are allowed to travel, path planning is essential in preventing contention and collisions. A performance metric which minimises total yard-vehicle usage, while producing robust traffic plans by encouraging both early starting and finishing of jobs is presented for different vehicle fleet sizes and job allocation scenarios. ©2010 IEEE

Infrared Emission from Supernova Remnants: Formation and Destruction of Dust

We review the observations of dust emission in supernova rem- nants (SNRs) and supernovae (SNe). Theoretical calculations suggest that SNe, particularly core-collapse, should make significant quantities of dust, perhaps as much as a solar mass. Observations of extragalactic SNe have yet to find anywhere near this amount, but this may be the result of observa- tional limitations. SN 1987A, in the process of transitioning from a SN to an SNR, does show signs of a significant amount of dust forming in its ejecta, but whether this dust will survive the passage of the reverse shock to be injected into the ISM is unknown. IR observations of SNRs have not turned up significant quantities of dust, and the dust that is observed is generally swept-up by the forward shock, rather than created in the ejecta. Because the shock waves also destroy dust in the ISM, we explore the question of whether SNe might be net destroyers, rather than net creators of dust in the universe.Comment: Published in the Springer Handbook of Supernova

All-passive pixel super-resolution of time-stretch imaging

Based on image encoding in a serial-temporal format, optical time-stretch imaging entails a stringent requirement of state-of-the- art fast data acquisition unit in order to preserve high image resolution at an ultrahigh frame rate --- hampering the widespread utilities of such technology. Here, we propose a pixel super-resolution (pixel-SR) technique tailored for time-stretch imaging that preserves pixel resolution at a relaxed sampling rate. It harnesses the subpixel shifts between image frames inherently introduced by asynchronous digital sampling of the continuous time-stretch imaging process. Precise pixel registration is thus accomplished without any active opto-mechanical subpixel-shift control or other additional hardware. Here, we present the experimental pixel-SR image reconstruction pipeline that restores high-resolution time-stretch images of microparticles and biological cells (phytoplankton) at a relaxed sampling rate (approx. 2--5 GSa/s) --- more than four times lower than the originally required readout rate (20 GSa/s) --- is thus effective for high-throughput label-free, morphology-based cellular classification down to single-cell precision. Upon integration with the high-throughput image processing technology, this pixel-SR time- stretch imaging technique represents a cost-effective and practical solution for large scale cell-based phenotypic screening in biomedical diagnosis and machine vision for quality control in manufacturing.Comment: 17 pages, 8 figure

Routine Pediatric Enterovirus 71 Vaccination in China: a Cost-Effectiveness Analysis

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Spatial and temporal dynamics of superspreading events in the 2014-2015 West Africa Ebola epidemic

The unprecedented scale of the Ebola outbreak in Western Africa (2014–2015) has prompted an explosion of efforts to understand the transmission dynamics of the virus and to analyze the performance of possible containment strategies. Models have focused primarily on the reproductive numbers of the disease that represent the average number of secondary infections produced by a random infectious individual. However, these population-level estimates may conflate important systematic variation in the number of cases generated by infected individuals, particularly found in spatially localized transmission and superspreading events. Although superspreading features prominently in first-hand narratives of Ebola transmission, its dynamics have not been systematically characterized, hindering refinements of future epidemic predictions and explorations of targeted interventions. We used Bayesian model inference to integrate individual-level spatial information with other epidemiological data of community-based (undetected within clinical-care systems) cases and to explicitly infer distribution of the cases generated by each infected individual. Our results show that superspreaders play a key role in sustaining onward transmission of the epidemic, and they are responsible for a significant proportion (∼61%) of the infections. Our results also suggest age as a key demographic predictor for superspreading. We also show that community-based cases may have progressed more rapidly than those notified within clinical-care systems, and most transmission events occurred in a relatively short distance (with median value of 2.51 km). Our results stress the importance of characterizing superspreading of Ebola, enhance our current understanding of its spatiotemporal dynamics, and highlight the potential importance of targeted control measures

Leptospirosis in American Samoa – Estimating and Mapping Risk Using Environmental Data

Leptospirosis is the most common bacterial infection transmitted from animals to humans. Infected animals excrete the bacteria in their urine, and humans can become infected through contact with animals or a contaminated environment such as water and soil. Environmental factors are important in determining the risk of human infection, and differ between ecological settings. The wide range of risk factors include high rainfall and flooding; poor sanitation and hygiene; urbanisation and overcrowding; contact with animals (including rodents, livestock, pets, and wildlife); outdoor recreation and ecotourism; and environmental degradation. Predictive risk maps have been produced for many infectious diseases to identify high-risk areas for transmission and guide allocation of public health resources. Maps are particularly useful where disease surveillance and epidemiological data are poor. The objectives of this study were to estimate leptospirosis seroprevalence at geographic locations based on environmental factors, produce a predictive disease risk map for American Samoa, and assess the accuracy of the maps in predicting infection risk. This study demonstrated the value of geographic information systems and disease mapping for identifying environmental risk factors for leptospirosis, and enhancing our understanding of disease transmission. Similar principles could be used to investigate the epidemiology of leptospirosis in other areas

Kajian keratan rentas mengenai pengetahuan, sikap dan amalan terhadap pencegahan demam denggi di Kampung Belawai, Sarikei dari 20 Jun hingga 5 Ogos 2000

A cross-sectional study was carried out in Kampung Belawai, Sarikei to assess the knowledge, attitude and practice of the villagers towards the prevention of Dengue Fever. The study was conducted from 20 July 2000 to 5 August 2000 by fourth year medical students from Faculty of Medicine and Health Sciences, Universiti Malaysia Sarawak (UNIMAS). A total of 232 respondents were selected based on systematic random sampling method and were interviewed by using a set of pre-tested questionnaire. A presumptive survey on Aedes larvae infestation rate was also carried out together with the interview. The majority of the respondents were female (61.3%). The results showed that the mean score for knowledge, attitude and practice of the general population was 53.5%, 69.7% and 45.7%, respectively. There was also significant association between knowledge, attitude and practice with sociodemographic factors such as age, education level and the household income. The Aedes larvae survey showed that the Breteau Index was 54.7, House Index was 33.6 and Container Index was found to be 14.4%. Pottery was the commonest container found to be infested with Aedes larvae. After the survey, an intervention program by the theme of `Hapuskan Denggi, Bekrwai Boleh! ' was carried out on 22nd and 23`d July 2000 at Kampung Belawai to raise the knowledge, attitude and practice of dengue prevention among the target population. The intervention program was also aimed to reduce the Aedes larvae infestation rate. It is recommended that continuous health education in small groups to be implemented among the target population to improve their knowledge, attitude and practice towards the prevention of Dengue Fever

The prevalence and experience of oral diseases in Adelaide nursing home residents

The document attached has been archived with permission from the Australian Dental Association. An external link to the publisher’s copy is included.Background: The twenty-first century will see the evolution of a population of dentate older Australians with dental needs very different from those of older adults in past years. This study provided comprehensive information concerning oral disease prevalence in older South Australian nursing home residents. Methods: This paper presents cross-sectional baseline results. Results: Most of the 224 residents, from seven randomly selected nursing homes, were functionally dependent, medically compromised, cognitively impaired and behaviourally difficult older adults who presented many complex challenges to carers and to dental professionals. Two-thirds (66 per cent) were edentulous with many dental problems and treatment needs. Dentate residents had a mean of 11.9 teeth present, higher than previously reported. The prevalence and experience of coronal and root caries and plaque accumulation was very high in dentate residents; especially males, those admitted more than three years previously, those who ate fewer food types and those who were severely cognitively impaired. These residents had more retained roots, decayed teeth and missing teeth, and fewer filled teeth when compared with data for community-dwelling older adults. Conclusions: This study highlighted the poor oral health status of these nursing home residents and the great impact of dementia on their high levels of oral diseases.JM Chalmers, C Hodge, JM Fuss, AJ Spencer, KD Carte

Ezrin interacts with the SARS coronavirus spike protein and restrains infection at the entry stage

© 2012 Millet et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Background: Entry of Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) and its envelope fusion with host cell membrane are controlled by a series of complex molecular mechanisms, largely dependent on the viral envelope glycoprotein Spike (S). There are still many unknowns on the implication of cellular factors that regulate the entry process. Methodology/Principal Findings: We performed a yeast two-hybrid screen using as bait the carboxy-terminal endodomain of S, which faces the cytosol during and after opening of the fusion pore at early stages of the virus life cycle. Here we show that the ezrin membrane-actin linker interacts with S endodomain through the F1 lobe of its FERM domain and that both the eight carboxy-terminal amino-acids and a membrane-proximal cysteine cluster of S endodomain are important for this interaction in vitro. Interestingly, we found that ezrin is present at the site of entry of S-pseudotyped lentiviral particles in Vero E6 cells. Targeting ezrin function by small interfering RNA increased S-mediated entry of pseudotyped particles in epithelial cells. Furthermore, deletion of the eight carboxy-terminal amino acids of S enhanced S-pseudotyped particles infection. Expression of the ezrin dominant negative FERM domain enhanced cell susceptibility to infection by SARS-CoV and S pseudotyped particles and potentiated S-dependent membrane fusion. Conclusions/Significance: Ezrin interacts with SARS-CoV S endodomain and limits virus entry and fusion. Our data present a novel mechanism involving a cellular factor in the regulation of S-dependent early events of infection.This work was supported by the Research Grant Council of Hong Kong (RGC#760208)and the RESPARI project of the International Network of Pasteur Institutes

Global prospective case series of ERCPs using a single-use duodenoscope

Background The first commercialized single-use duodenoscope was cleared by the US Food and Drug Administration in December 2019. Data regarding endoscopic retrograde cholangiopancreatography (ERCP) using a single-use duodenoscope are needed on a broader range of cases conducted by endoscopists with varying levels of experience in a wide range of geographic areas. Methods 61 endoscopists at 22 academic centers in 11 countries performed ERCP procedures in adult patients aged ? 18. Outcomes included ERCP completion for the intended indication, rate of crossover to a reusable endoscope, device performance ratings, and serious adverse events (SAEs). Results Among 551 patients, 236 (42.8 %) were aged &gt;65, 281 (51.0 %) were men, and 256 (46.5 %) had their procedure as an inpatient. ERCPs included 196 (35.6 %) with American Society for Gastrointestinal Endoscopy complexity of grades 3 4. A total of 529 ERCPs (96.0 %) were completed: 503 (91.3 %) using only the single-use duodenoscope, and 26 (4.7 %) with crossover to a reusable endoscope. There were 22 ERCPs (4.0 %) that were not completed, of which 11 (2.0 %) included a crossover and 11 (2.0 %) were aborted cases (no crossover). Median ERCP completion time was 24.0 minutes. Median overall satisfaction with the single-use duodenoscope was 8.0 (scale of 1 to 10 [best]). SAEs were reported in 43 patients (7.8 %), including 17 (3.1 %) who developed post-ERCP pancreatitis. Conclusions In academic medical centers over a wide geographic distribution, endoscopists with varying levels of experience using the first marketed single-use duodenoscope had good ERCP procedural success and reported high performance ratings for this device.</p