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Human stampedes (HS) may result in mass casualty incidents (MCI) that arise due to complex interactions between individuals, collective crowd, and space, which have yet to be described from a physics perspective. HS events were analyzed using basic physics principles to better understand the dynamic kinetic variables that give rise to HS.
A literature review was performed of medical and nonmedical sourced databases, Library of Congress databases, and online sources for the term human stampedes resulting in 25,123 references. Filters were applied to exclude nonhuman events. Retrieved references were reviewed for a predefined list of physics terms. Data collection involved recording frequency of each phrase and physics principle to give the final proportions of each predefined principle used a single-entry method for each of the 105 event reports analyzed. Data analysis was performed using the R statistics packages “tidyverse”, “psych”, “lubridate”, and “Hmisc” with descriptive statistics used to describe the frequency of each observed variable.
Of the 105 reports of HS resulting in injury or death reviewed, the following frequency of terms were found: density change in a limited capacity, 45%; XY-axis motion failure, 100%; loss of proxemics, 100%; deceleration with average velocity of zero, 90%; Z-axis displacement pathology (falls), 92%; associated structure with nozzle effect, 93%; and matched fluid dynamic of high pressure stagnation of mass gathering, 100%.
Description or reference to principles of physics was seen in differing frequency in 105 reports. These include XY-axis motion failure of deceleration that leads to loss of human to human proxemics, and high stagnation pressure resulting in the Z-axis displacement effect (falls) causing injury and death. Real-time video-analysis monitoring of high capacity events or those with known nozzle effects for loss of proxemics and Z-axis displacement pathology offers the opportunity to prevent mortality from human stampedes.
A high selective dual band and miniaturized electromagnetic band gap (EBG) unit cell is presented in this paper. The analysis and characterization of the new cell are explained. The modified compact EBG unit cell is based on cutting two inverted U-shaped slots inside the typical mushroom-like EBG. The modified EBG has a 70% size reduction. The dual-band functionality of the structure is confirmed by applying it in a dual-notch ultra-wideband antenna (3.1–10.6 GHz), and the notch frequencies are 5.2 and 5.8 GHz. The dual-band functionality has advantages of a highly selective bandpass between them. The antenna can suppress interference frequencies in less than 100 MHz bandwidth without affecting the antenna performance in the whole bandwidth. Presented results are addressed in terms of circuit modeling, 3D full-wave simulations, and measurements.
Human Stampedes (HS) occur at religious mass gatherings. Religious events have a higher rate of morbidity and mortality than other events that experience HS. This study is a subset analysis of religious event HS data regarding the physics principles involved in HS, and the associated event morbidity and mortality.
To analyze reports of religious HS to determine the initiating physics principles and associated morbidity and mortality.
Thirty-four reports of religious HS were analyzed to find shared variables. Thirty-three (97.1%) were written media reports with photographic, drawn, or video documentation. 29 (85.3%) cited footage/photographs and 1 (2.9%) was not associated with visual evidence. Descriptive phrases associated with physics principles contributing to the onset of HS and morbidity data were extracted and analyzed to evaluate frequency before, during, and after events.
34 (39.1%) reports of HS found in the literature review were associated with religious HS. Of these, 83% were found to take place in an open space, and 82.3% were associated with population density changes. 82.3% of events were associated with architectural nozzles (small streets, alleys, etc). 100% were found to have loss of XY-axis motion and 89% reached an average velocity of zero. 100% had loss of proxemics and 91% had associated Z-axis displacement (falls). Minimum reported attendance for a religious HS was 3000. 100% of religious HS had reported mortality at the event and 56% with further associated morbidity.
HS are deadly events at religious mass gatherings. Religious events are often recurring, planned gatherings in specific geographic locations. They are frequently associated with an increase in population density, loss of proxemics and velocity, followed by Z-axis displacements, leading to injury and death. This is frequently due to architectural nozzles, which those organizing religious mass gatherings can predict and utilize to mitigate future events.
Children represent a particularly vulnerable population in disasters. Disaster Risk Reduction refers to a systematic approach to identifying, assessing, and reducing risks of disaster through sets of interventions towards disaster causes and population vulnerabilities. Disaster Risk Reduction through the education of the population, and especially children, is an emerging field requiring further study.
To test the hypothesis that an educational program on Disaster Risk Reduction can induce a sustained improvement in knowledge, risk perception, awareness, and attitudes toward preparedness behavior of children.
A Disaster Risk Reduction educational program for students aged 10-12 was completed in an earthquake-prone region of Jordan (Madaba). Subject students (A) and control groups of similarly aged untrained children in public (B) and private (C) schools were surveyed one year after the program. Surveys focused on disaster knowledge, risk perception, awareness, and preparedness behavior. Likert scales were used for some questions and binary yes/no for others. Results were collated and total scores averaged for each section. Average scores were compared between groups and analyzed using SPSS.
Students who had completed the Disaster Risk Reduction program were found through Levene’s test to have statistically significant improvement in earthquake knowledge (5.921 vs. 4.55 vs. 5.125), enhanced risk perception (3.966 vs. 3.580 vs. 3.789), and improved awareness of earthquakes (4.652 vs. 3.293 vs. 4.060) with heightened attitudes toward preparedness behavior (8.008 vs. 6.517 vs. 7.597) when compared to untrained public and private school control groups, respectively.
Disaster Risk Reduction education programs can have lasting impacts when applied to children. They can improve students’ knowledge, risk perception, awareness, and attitudes towards preparedness. Further work is required to determine the frequency of re-education required and appropriate age groups for educational interventions.
The origins of agriculture in South-west Asia is a topic of continued archaeological debate. Of particular interest is how agricultural populations and practices spread inter-regionally. Was the Arabian Neolithic, for example, spread through the movement of pastoral groups, or did ideas perhaps develop independently? Here, the authors report on recent excavations at Alshabah, one of the first Neolithic sites discovered in Northern Arabia. The site’s material culture, environmental context and chronology provide evidence suggesting that well-adapted, seasonally mobile, pastoralist groups played a key role in the Neolithisation of the Arabian Peninsula.
Co-circulation of Chikungunya and Dengue viral infections (CHIKV and DENV) have been reported mainly due to transmission by common Aedes vector. The purpose of the study was to identify and characterise the circulating strains of CHIKV and DENV in DENV endemic region of New Delhi during 2016. CHIKV and DENV were identified in the blood samples (n = 130) collected from suspected patients by RT-PCR. CHIKV was identified in 26 of 65 samples (40%). Similarly, DENV was detected in 48 of 120 samples (40%). Co-infection with both the viruses was identified in five (9%) of the samples. Interestingly, concurrent infection with DENV, CHIKV and Plasmodium vivax was detected in two samples. CHIKV strains (n = 11) belonged to the ECSA genotype whereas DENV-3 sequences (n = eight) clustered in Genotype III by phylogenetic analysis. Selection pressure of E1 protein of CHIKV and CprM protein of DENV-3 revealed purifying selection with four and two positive sites, respectively. Four amino acids of the CHIKV were positively selected and had high entropy suggesting probable variations. Co-circulation of both viruses in DENV endemic regions warrants effective monitoring of these emerging pathogens via comprehensive surveillance for implementation of effective control measures.
To explore the effects of maternal nutrition on offspring muscle characteristics, a total of 56 sows were assigned to one of the four dietary groups during gestation: control (CON), or control diets supplemented with methyl donor (MET), bisphenol A (BPA), and combined BPA and MET (BPA+MET). Compared with CON offspring, MET offspring showed a higher meat redness value, but lower glycogen content in the longissimus thoracis (LT). Moreover, compared with CON offspring, MET offspring showed lower LT glycogen synthase (GS) mRNA levels at birth and the finishing stage, and increased methylation at the GS promoter. Prenatal BPA exposure reduced the pH and redness value of meat, but increased the lightness value, lactate content, glycolytic potential and lactate dehydrogenase (LDH) enzyme activity in the LT muscle. Prenatal BPA exposure increased LDH mRNA levels in the LT muscle at birth and the finishing stage, and reduced methylation at the LDH promoter. Thus, maternal MET affects muscle GS and LDH expression via DNA methylation, thereby resulting in persistent effects on pork quality.
Dengue fever is an arthropod-borne viral infection that has become endemic in several parts of India including Delhi. We studied occurrence of co-infection with dengue viruses during an outbreak in New Delhi, India in 2014. For the present study, blood samples collected from symptomatic patients were analysed by RT–PCR. Eighty percent of the samples were positive for dengue virus. The result showed that DENV-1 (77%) was the predominant serotype followed by DENV-2 (60%). Concurrent infection with more than one serotype was identified in 43% of the positive samples. Phylogenetic analysis clustered DENV-1 strains with the American African and DENV-2 strains in Cosmopolitan genotypes. Four common amino-acid mutations were identified in the envelope gene of DENV-1 sequences (F337I, A369T, V380I and L402F) and one common mutation (N390S) in the DENV-2 sequences. Further analysis revealed purifying selection in both the serotypes. A significant number of patients were co-infected with DENV-1 and DENV-2 serotypes. Although we do not have direct evidence to demonstrate co-evolution of these two stereotypes, nonetheless their simultaneous occurrence does indicate that they are favoured by evolutionary forces. An ongoing surveillance and careful analysis of future outbreaks will strengthen the concept of co-evolution or otherwise. Whether the concurrent dengue viral infection is correlated with disease severity in a given population is another aspect to be pursued. This study is envisaged to be useful for future reference in the context of overall epidemiology.
Incineration or disposal of carbon fiber waste from the aircraft industry leads to serious energy consumption and environmental pollution. The use of this waste as reinforcement is a wise approach to appreciate the high performance of the carbon fiber. In this study, the sliding wear and frictional behavior of recycled carbon fiber prepreg (rCFP) reinforced polypropylene (PP) prepared via melt compounding method using an internal mixer were studied. The samples were categorized into PP reinforced by carbon fiber with resin (A) and carbon fiber without resin (B). Pin-on-disc method was utilized to evaluate the effect of rCFP content and physical condition of fibers on tribological performance of the composites. The results were supported by morphological analyses using scanning electron microscopy. It was found that polymer composites B for rCFP without resin exhibited better tribological performance than composites category-A. The addition of rCFP into PP was observed to increase its wear resistance with minimum coefficient of friction achieved at 3 wt% of rCFP content for both polymer composites.
Surveillance data on the burden of pertussis in Asian adults are limited. This cross-sectional study evaluated the prevalence of serologically confirmed pertussis in adults with prolonged cough in Malaysia, Taiwan and Thailand. Adults (⩾19 years) with cough lasting for ⩾14 days without other known underlying cause were enrolled from outpatient clinics of seven public and/or private hospitals. Single blood samples for anti-pertussis toxin antibodies (anti-PT IgG) were analysed and economic impact and health-related quality of life (EQ-5D) questionnaires assessed. Sixteen (5·13%) of the 312 chronically coughing adults had serological evidence of pertussis infection within the previous 12 months (anti-PT IgG titre ⩾62·5 IU/ml). Three of them were teachers. Longer duration of cough, paroxysms (75% seroconfirmed, 48% non-seroconfirmed) and breathlessness/chest pain (63% seroconfirmed, 36% non-seroconfirmed) were associated with pertussis (P < 0·04). Of the seroconfirmed patients, the median total direct medical cost per pertussis episode in public hospitals (including physician consultations and/or emergency room visits) was US$13 in Malaysia, US$83 in Taiwan (n = 1) and US$26 in Thailand. The overall median EQ-5D index score of cases was 0·72 (range 0·42–1·00). Pertussis should be considered in the aetiology of adults with a prolonged or paroxysmal cough, and vaccination programmes considered.
An unexpected new source of tin was recently located at Hisarcık, in the foothills of the Mount Erciyes volcano in the Kayseri Plain, close to the Bronze Age town of Kültepe, ancient Kanesh and home to a colony of Assyrian traders. Volcanoes in Turkey have always been associated with obsidian sources but were not known to be a major source of heavy metals, much less tin. X-ray fluorescence analyses of the Hisarcık ores revealed the presence of minerals suitable for the production of complex copper alloys, and sufficient tin and arsenic content to produce tin-bronze. These findings revise our understanding of bronze production in Anatolia in the third millennium BC and demand a re-evaluation of Assyrian trade routes and the position of the Early Bronze Age societies of Anatolia within that network.
We aimed to reparameterize and validate an existing dengue model, comprising an entomological component (CIMSiM) and a disease component (DENSiM) for application in Malaysia. With the model we aimed to measure the effect of importation rate on dengue incidence, and to determine the potential impact of moderate climate change (a 1 °C temperature increase) on dengue activity. Dengue models (comprising CIMSiM and DENSiM) were reparameterized for a simulated Malaysian village of 10 000 people, and validated against monthly dengue case data from the district of Petaling Jaya in the state of Selangor. Simulations were also performed for 2008-2012 for variable virus importation rates (ranging from 1 to 25 per week) and dengue incidence determined. Dengue incidence in the period 2010–2012 was modelled, twice, with observed daily weather and with a 1 °C increase, the latter to simulate moderate climate change. Strong concordance between simulated and observed monthly dengue cases was observed (up to r = 0·72). There was a linear relationship between importation and incidence. However, a doubling of dengue importation did not equate to a doubling of dengue activity. The largest individual dengue outbreak was observed with the lowest dengue importation rate. Moderate climate change resulted in an overall decrease in dengue activity over a 3-year period, linked to high human seroprevalence early on in the simulation. Our results suggest that moderate reductions in importation with control programmes may not reduce the frequency of large outbreaks. Moderate increases in temperature do not necessarily lead to greater dengue incidence.
In this paper, a new configuration of dual-band, dual-polarized microstrip antenna applicable to mobile base stations is proposed. The concept behind the new design is the use of an artificial magnetic conductor (AMC) structure that operates in the required two bands beneath a radiating diamond shaped slot. The choice of the diamond-shaped slot is due to its support of an infinite number of resonant modes where the dimensions of the diamond shape have more degree of freedom that controls the excited modes when compared to the rectangular slot. The proposed antenna works over the 870–960 MHz (GSM850/GSM900) band and the 1710–2170 MHz (DCS1800/PCS1900/UMTS2100) bands for mobile communication systems. The antenna is suitable for transmitting and receiving mobile signals since it has two ports of orthogonal polarization. The antenna is fabricated on a combination of FR4 dielectric substrate and foam layers in order to achieve low cost. The proposed antenna yields high isolation between its two ports not exceeding −30 dB and a front-to-back ratio exceeding 15 dB. The average antenna gains are about 6.6 dBi at the GSM850/GSM900, 7.1 dBi at the DCS1800/PCS1900, and 6.8 dBi at the UMTS2100 bands. The theory of radiation is proved analytically and verified by comparing its results with some simulated results. Finally, a good agreement between the simulated and measured results is noticed.
This paper is a numerical simulation that was made in the three-dimensional flow, carried out in a modified centrifugal compressor, having vaned diffuser stage, used as an auto-motive turbo charger. Moreover, the performance of the centrifugal compressor was dependent on the proper matching between compressor impeller and vaned diffuser, influencing significantly surge and the efficiency of centrifugal compressor stages. In addition, a modified compressor impeller, coupled with vane and vaneless diffuser, has been found to have similar internal flow patterns for both the vaneless and vaned diffuser design. The vaned diffuser effect has been paid particular attention in terms of better analysis where the diffuser was designed for high sub-sonic inlet conditions. Another aim of this research was to study and simulate the effect of vaned diffuser on the performance of a centrifugal compressor. The simulation was undertaken by using a commercial software, the so-called ANSYS CFX, to predict numerically the performance in terms of pressure ratio, poly tropic efficiency and mass flow rate for the centrifugal compressor stage. The results were generated from CFD and were analyzed for better understanding of the fluid flow through centrifugal compressor stage. Conclusively, it was observed that the effect of the vaned diffuser is to convert the kinetic energy into a high static pressure after analyzing the results of the simulation.
Infants are obligate nasal breathers. Cleft palate closure may result in upper airway compromise. We describe children undergoing corrective palatal surgery who required unplanned airway support.
Tertiary referral unit.
Retrospective study (2007–2009) of 157 cleft palate procedures (70 primary procedures) in 43 patients. Exclusion criteria comprised combined cleft lip and palate, secondary palate procedure, and pre-existing airway support.
The children's mean age was 7.5 months and their mean weight 7.72 kg. Eight children were syndromic, and eight underwent pre-operative sleep studies (five positive, three negative). Post-operatively, five developed respiratory distress and four required oxygen, both events significantly associated with pre-operative obstructive sleep apnoea (p = 0.001 and 0.015, respectively). Four desaturated within 24 hours. Five required a nasopharyngeal airway. Hospital stay (mean, 4 days) was significantly associated with obstructive sleep apnoea (p = 0.002) and nasopharyngeal airway insertion (p = 0.017).
Pre-operative obstructive sleep apnoea correlated significantly with post-operative respiratory distress, supplementary oxygen requirement, nasopharyngeal airway insertion and hospital stay. We recommend pre-operative sleep investigations for all children undergoing cleft palate repair, to enable appropriate timing of the procedure.
Several new concepts are used to describe contraceptive use histories for nearly 1200 women in Peninsular Malaysia. These histories are summarized by 81 episode histories. Transition matrices provide useful summaries of the changes women make in their contraceptive practice from one pregnancy interval to the next. Data from the mid-1940s to mid-1970s, during which period there was a dramatic increase in contraceptive use, reveal considerable inertia in individual couples' contraceptive practice. Persistence with a method was greater the less effective the method: while 86% of couples using no method in one interval used no method in the next, only 56% of couples using the pill in one interval also used it in the next. Virtually all transitions are of three types: continuation with the same method, a change from no method to some method, or a change from some method to no method. For only 1% of all pregnancies did couples use one contraceptive method before a pregnancy and a different method after the pregnancy. Differences are examined by calendar year and education.
Magnetite (Fe3O4) nanoparticles are prime candidates for biomedical applications due to their biocompatibility and good magnetic properties. However, magnetite is highly susceptible to oxidation when exposed to the atmosphere. In order to preserve their properties, it is important for the particles to maintain their magnetite phase. In this study, magnetite nanoparticles were prepared using the conventional co3precipitation of ferrous (Fe2+) and ferric (Fe3+) chloride salt solutions with sodium hydroxide (NaOH). Thermogravimetric analysis (TGA) was subsequently carried out to identify the transition temperatures. Energy Dispersive X3Ray (EDX) spectrum shows the presence of impurities, such as sodium (Na) and chloride (Cl) ions in the as3synthesized magnetite nanoparticles. The as3synthesized samples were then calcined in a chamber furnace according to TGA data. The calcined samples were next characterised by X3ray Powder Diffraction (XRD), Transmission Electron Microscopy (TEM) and Vibrating Sample Magnetometer (VSM) to determine the changes in phase and magnetic properties of the nanoparticles as a function of different calcination temperatures.
Ag-Cu alloy nanoparticles were prepared by rapid condensation of metal flux obtained by the simultaneous evaporation of high purity Cu and Ag wires on a tungsten boat in the presence of circulating He gas. Structural properties of the samples prepared at different conditions were investigated by using X-ray diffraction (XRD), transmission electron microscopy (TEM) and selected area diffraction (SAD) patterns. X-ray diffraction patterns showed that particles were phase separated. The particle size obtained either from Scherer's formula or the TEM images show no systematic change on the size of either Cu or Ag particles in the evaporation temperature range between 800 and 1400 °C. By using lattice constant values and Vegard's law, the composition of the particles was calculated to be 6.6 vol% Cu in Ag. Electron diffraction images revealed that particles were softly agglomerated; these electron diffraction results were also consistent with XRD results regarding phase separation. Individual diffraction rings of the Cu and Ag were observed in the SAD patterns.