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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.
Little is known about the role of affectionate behaviours — factors traditionally understood within the context of romantic relationships — in uncommitted ‘casual sex’ encounters. In a sample of U.S. undergraduate emerging adults aged 18–25 years (N = 639) we conducted a preliminary internet-based questionnaire investigation into the role of affectionate behaviours — operationalised here as cuddling, spending the night and cuddling, foreplay, and eye gazing — across two sexual relationship contexts: (committed) traditional romantic relationships and (uncommitted) casual sex encounters. While affectionate behaviours were desired more often in romantic relationships than in casual sexual encounters, many respondents (both men and women) engaged in these affectionate behaviours during casual sexual encounters as well. This was especially pronounced in those who expressed a preference for casual sex encounters over romantic relationships: in a casual sex context these participants were about 1.5 times as likely to cuddle, 1.5 times as likely to spend the night and cuddle, and nearly 5 times as likely to engage in foreplay with a partner. The current study emphasises the importance of considering relationship context in sexuality and relationship research, and the need for further theoretical and empirical research on dimensions of intimacy, including affection, in people's diverse romantic and sexual lives.
Discovery of strongly-lensed gravitational wave (GW) sources will unveil binary compact objects at higher redshifts and lower intrinsic luminosities than is possible without lensing. Such systems will yield unprecedented constraints on the mass distribution in galaxy clusters, measurements of the polarization of GWs, tests of General Relativity, and constraints on the Hubble parameter. Excited by these prospects, and intrigued by the presence of so-called “heavy black holes” in the early detections by LIGO-Virgo, we commenced a search for strongly-lensed GWs and possible electromagnetic counterparts in the latter stages of the second LIGO observing run (O2). Here, we summarise our calculation of the detection rate of strongly-lensed GWs, describe our review of BBH detections from O1, outline our observing strategy in O2, summarize our follow-up observations of GW170814, and discuss the future prospects of detection.
This paper presents a novel framework, based on traditional system safety modelling approaches, for the representation and comparison of airworthiness aviation frameworks. A disparate array of military airworthiness frameworks have emerged due to a lack of standardisation and the absence of a recognised organisation needed for the harmonisation of military regulatory frameworks.. The complexity and subsequent cost in inter-agency recognition of existing certification programs has led to the establishment of a European forum of military airworthiness authorities. The forum is working towards establishing a common regulatory framework across its European member states. The common framework provides the systematic basis for a certification of military aircraft that can be readily recognised by all of the member states. This will have many cost and efficiency benefits for the EU. The framework and recognition process have recently been accepted as a method for establishing recognition outside of Europe, with some identified shortfalls. This paper establishes a method for overcoming these shortfalls for nations outside of europe. The Product-Behaviour-Process (PBP) Bow-Tie, which is a novel application of the traditional bowtie risk modelling tool, derives test points that capture the airworthiness attestations for the high-level engineering lifecycle processes of design, production and maintenance. The proposed framework is used to provide a comparison between the Australian Defence Force and United States Army regulatory frameworks. The comparative case-study clearly demonstrates the benefit of the PBP Bow-Tie model in its ability to systematically represent the disparate regulatory frameworks. A novel representation of the output is also described, which facilitates a visual comparison of the results. The application of the PBP Bow-Tie framework to the case-study of regulatory frameworks reveals significant differences that need to be addressed in order for inter-agency recognition.
Euclid is the next ESA mission devoted to cosmology. It aims at observing most of the extragalactic sky, studying both gravitational lensing and clustering over ~15,000 square degrees. The mission is expected to be launched in year 2020 and to last six years. The sheer amount of data of different kinds, the variety of (un)known systematic effects and the complexity of measures require efforts both in sophisticated simulations and techniques of data analysis. We review the mission main characteristics, some aspects of the the survey and highlight some of the areas of interest to this meeting.
Positron emission tomography and post-mortem studies of the number of somatodendritic 5-hydroxytryptamine1A (5-HT1A) autoreceptors in raphé nuclei have found both increases and decreases in depression. However, recent genetic studies suggest they may be increased in number and/or function. The current study examined the effect of buspirone on the electroencephalographic (EEG) centroid frequency, a putative index of somatodendritic 5-HT1A receptor functional status, in a cohort of medication-free depressed patients and controls.
A total of 15 depressed patients (nine male) and intelligence quotient (IQ)-, gender- and age-matched healthy controls had resting EEG recorded from 29 scalp electrodes prior to and 30, 60 and 90 min after oral buspirone (30 mg) administration. The effect of buspirone on somatodendritic 5-HT1A receptors was assessed by calculating the EEG centroid frequency between 6 and 10.5 Hz. The effect of buspirone on postsynaptic 5-HT1A receptors was assessed by measuring plasma growth hormone, prolactin and cortisol concentrations.
Analysis of variance revealed a significantly greater effect of buspirone on the EEG centroid frequency in patients compared with controls (F1,28 = 6.55, p = 0.016). There was no significant difference in the neuroendocrine responses between the two groups.
These findings are consistent with an increase in the functional status of somatodendritic, but not postsynaptic, 5-HT1A autoreceptors, in medication-free depressed patients in line with hypotheses based on genetic data. This increase in functional status would be hypothesized to lead to an increase in serotonergic negative feedback, and hence decreased release of 5-HT at raphé projection sites, in depressed patients.
Pyrochlores based on the general composition CaLnZrNbO7 (where Ln = La, Nd, Sm, Gd and Ho) have been prepared, and irradiated through the crystalline-amorphous transition, with 1 MeV Kr ions at the IVEM-TANDEM user facility. The obtained critical temperatures show a decrease from La to Gd (∼680 K to ∼230 K), with Ho being resistant to amorphisation at 50K. The results suggest that the amorphisation cross section for these materials is directly related to the Ln component.
Ceramics based on the general compositions CaLnXNbO7 (where Ln = La, Nd and Sm, and X=Zr and Sn) have been prepared, and irradiated with 1 MeV Kr ions at the IVEM-TANDEM user facility. The radiation tolerance of these materials has been found to be less than Zr and Hf equivalents. The results also suggest that the amorphisation cross section for these materials is related to the Ln component, and is similar to those observed for Zr and Hf equivalents.
Anterior tongue reduction is indicated when macroglossia causes problems with oral hygiene, airway compromise, deglutition, articulation or orthognathic complications. Causes of macroglossia include hypothyroidism, mucopolysaccharide and lipid storage disease, lymphangioma, haemangioma, neurofibroma, and muscular macroglossia. This paper presents an 11-year experience of anterior tongue reduction at Great Ormond Street Hospital.
Retrospective study of patient medical records identified from the hospital ENT database. Anterior wedge resection was the preferred technique.
Anterior tongue reduction was performed on 18 patients, due to cystic hygroma with tongue involvement (nine patients), Beckwith–Wiedemann syndrome (eight) and Down's syndrome (one). Anterior wedge resection was preferred, using electrocautery in the majority, except for four cases involving CO2 laser. All but one patient had a good surgical outcome (i.e. tongue in mouth at rest). One patient subsequently required multiple laser procedures for recurrent macroglossia.
Anterior tongue reduction can be a safe procedure, with limited post-operative morbidity, consistently resulting in good surgical outcomes and improvement in macroglossia symptoms. Speech development does not appear to be adversely affected.
A model has been developed that simulates oxygen precipitation in silicon wafers during high temperature device processing. The approach used to calculate the nucleation and growth of oxygen precipitates is radically different from other approaches presented in the literature. A discrete rate equation representation of nucleation and growth has been transformed into a continuum representation in the form of a partial differential equation. This partial differential equation describing both the statistical clustering of oxygen during nucleation and the diffusion driven transport during precipitate growth is solved continuously starting from crystal growth through any arbitrary time-dependent temperature process.
A new method for the nucleation of oxygen precipitates in Czochralski silicon is described. The temperature is ramped at approximately 100°C/hr from a very low value, near 400°C, to the highest temperature used for subsequent process steps. The technique generates a larger precipitate number density and a greater volume fraction of precipitated oxygen than standard isothermal nucleation anneals. The morphology of the precipitates changes from 0.lum sizéd (100) platelets to small particles unresovable by TEM. The new temperature ramping technique can reduce the time needed for precipitate nucleation by at least a factor of three. The details of oxygen precipitation can be totally controlled by adjusting the temperature ramp rate as a function of time.
Two-types of vertically aligned multi-walled carbon nanotubes (VA-MWNTs) are evaluated as the protective coatings against ion erosion in electric propulsion systems. A series of experiments have been conducted to understand the erosion rate and erosion mechanism of these VA-MWNTs. These experiments were carried out with Xe propellant at an ion current density of 5 mA/cm2. We found that the erosion rates of both types of VA-MWNTs were changing with time. Such a nonlinear erosion process is explained according to a possible erosion mechanism.
Three different types of bivalent influenza virus vaccine, a whole virus, an aqueous-surface-antigen vaccine and an adsorbed-surface-antigen vaccine were tested at three dosage levels in volunteers primed with respect to only one of the haemagglutinin antigens present in the vaccines.
The local and systemic reactions to all three vaccine types were mild in nature and, following first immunization, the aqueous-surface-antigen vaccine was the least reactogenic. The serum haemagglutination-inhibiting antibody response to the A/Victoria/75 component of the vaccines, to which the volunteer population was primed, was greatest following immunization with the aqueous-surface-antigen vaccine; the greatest antibody response to the A/New Jersey/76 component of the vaccines was observed following immunization with whole virus vaccine.
In the Milroy Lectures of this year, Professor Hewlett stated:—“There is some evidence to show that the germicidal power of emulsified disinfectants is greater than can be accounted for by the activity of the active constituent and theoretically seems likely, but we want some reliable experimental work in confirmation. It is ture that Chick and Martin have compared the germicidal value of higher tar acids emulsified in water and dissolved in alcohol, their results showing that the emulsified form was much more active; but the reliability of this work is vitiated by the fact that they have entirely failed to take into account the influence of alcohol in decreasing germicidal activity; for example in the case of phenol, which I dealt with in my last lecture”.
Intranasal vaccines of inactivated or living attentuated A2/Hong Kong influenza viruses were compared for clinical acceptability, serological effects and protective efficiency against natural epidemic influenza in a large industrial and clerical population.
Field experiments were conducted in Platte County, Missouri, during 2006 and 2007 to evaluate PRE, POST, and PRE followed by (fb) POST herbicide programs for the control of glyphosate-resistant waterhemp in soybean. All PRE fb POST treatments resulted in at least 66 and 70% control of glyphosate-resistant waterhemp in 2006 and 2007, respectively. Control of glyphosate-resistant waterhemp was less than 23% with lactofen and acifluorfen in 2006, but at least 64% in 2007. Variability in control likely resulted from differences in trial locations and a population of protoporphyrinogen oxidase (PPO)–resistant waterhemp at the Platte County site in 2006 compared with 2007. In both years, glyphosate resulted in less than 23% control of glyphosate-resistant waterhemp and provided the least control of all herbicide programs. Programs containing PRE herbicides resulted in waterhemp densities of less than 5 plants/m2, whereas the POST glyphosate treatment resulted in 38 to 70 plants/m2. Waterhemp seed production was reduced at least 78% in all PRE fb POST programs, from 55 to 71% in POST programs containing lactofen and acifluorfen and by only 21% in the POST glyphosate treatment. Soybean yields corresponded to the level of waterhemp control achieved in both years, with the lowest yields resulting from programs that provided poorest waterhemp control. PRE applications of S-metolachlor plus metribuzin provided one of the highest net incomes in both years and resulted in $271 to $340/ha greater net income than the glyphosate-only treatment. Collectively, the results from these experiments illustrate the effectiveness of PRE herbicides for the control of glyphosate-resistant waterhemp in glyphosate-resistant soybean and the inconsistency of PPO-inhibiting herbicides or PPO-inhibiting herbicide combinations for the control of waterhemp populations with multiple resistance to glyphosate and PPO-inhibiting herbicides.
The Spitzer Space Telescope has delivered impressive infrared images of numerous low-mass star forming regions at unprecedented sensitivity. In this paper we focus on their high-mass counterparts, the most massive HII regions in the Local Group: NGC3603 (MW), W49A (MW), 30 Doradus (LMC), NGC346 (SMC), and NGC604 (M33). The deep mid-IR images, taken with IRAC show the complex structure of the ISM, the interplay between ISM and stellar clusters, and reveal new sites of star formation. We compare the IRAC data with observations from Chandra and find good anti-correlations between the mid-IR and soft X-ray emission regions. We also investigate the commonalities and differences between the giant HII regions NGC604 and 30 Doradus.
Research on best management practices, including vegetative filter strips, is needed to evaluate the potential for reducing herbicides in surface runoff. Laboratory studies were conducted to determine the influence of different filter strip components on fluometuron adsorption. Samples were taken from a switchgrass filter strip (1-m wide) established on a Brooksville silty clay. Sampled components included switchgrass stems clipped to 4 cm, plant residue on the soil surface, and topsoil < 5-mm, 0.5- to 1-cm, 1- to 3-cm, and 3- to 5-cm deep. The filter strip topsoil samples contained 1.8, 2.2, 2.3, and 2.8% organic matter for the aforementioned depths, respectively, compared with 1.8% in soil collected from an adjacent cropped area. Fluometuron adsorption on each sample was compared at initial concentrations of 0.017, 0.5, 1.0, 2.0, and 4.0 mg L−1, the last of these representing four times the peak concentration in surface runoff. Fluometuron adsorption was greater in soil from filter strip areas than in soil from cropped areas. Averaged over concentration, the soil–water partition coefficient (Kd) value for soil 1- to 3-cm and 3- to 5-cm deep was greater than the value for soil from the cropped area. Stems and residue had Kd values 4.9- and 4.1-fold greater, respectively, than soil from the cropped area. Average adsorption coefficients normalized for organic carbon content (Koc) of soil < 5-mm and 3- to 5-cm deep from filter strip areas were greater than the values for soil from cropped areas.
Field studies were conducted in 1998 and 1999 to evaluate the sensitivity of a common sunflower population to acetolactate synthase (ALS)-inhibiting herbicides and evaluate alternative control methods for ALS-resistant common sunflower in soybean. Imazaquin, imazethapyr, imazamox, flumetsulam, chlorimuron, cloransulam, and CGA277476 provided 35 to 73% control of common sunflower with labeled rates. Postemergence glyphosate and sequential applications of bentazon effectively controlled ALS-resistant common sunflower. Although pendimethalin + imazaquin + imazethapyr preemergence followed by glyphosate postemergence with and without cultivation provided 100% control of ALS-resistant common sunflower, sequential applications of glyphosate provided net incomes approximately $50 to $110/ha higher than the alternative control methods. Pendimethalin preemergence followed by acifluorfen + bentazon postemergence followed by bentazon 10 d later provided the lowest overall weed control and net income. In treatments with a soil-applied herbicide followed by glyphosate postemergence, cultivation generally did not improve weed control. Soybean yields were the same comparing glyphosate with a soil-applied herbicide followed by glyphosate.