100 research outputs found
Resilience in education: An example from primary school in Fiji and technical vocational education and training
In the Pacific, the capacity of curriculum writers for integrating the content of climate change into their curricula and/or taught Resilience [Climate Change Adaptation (CCA) & Disaster Risk Reduction (DRR)] in education is limited. This paper described the findings of a 2018 study on the integration of climate change into primary and secondary schools’ curricula and taught resilience in education in TVET. It involves teachers (n = 30) from Kadavu and Levuka islands, curriculum writers and editors from the Ministry of Education, GIZ, SPC, and USP—in Fiji. An exploratory design was used to explore the curricula for Fiji and the EU PacTVET project at SPC. Information was collected from workshops and training events, interviews and project documents. Using BEKA (Benchmarking, Evidencing, Knowing, Applying) and the concept of ako (e.g. to study or educate), a model of climate change and resilience in education was designed as part of this research to help Pacific schools with their curricula. These results indicate how behavioural changes may shape Resilience, thus placing them in a better position to achieve the UNFCCC, the SDGs, the Sendai Framework and the Framework for Resilient Development in the Pacific (FRDP) targets and objectives by 2030 and beyond
Genetic relatedness among isolates of Shigella sonnei carrying class 2 integrons in Tehran, Iran, 2002–2003
<p>Abstract</p> <p>Background</p> <p><it>Shigella </it>spp. are major cause of diarrhoeal disease in both developing and developed countries. <it>Shigella sonnei </it>is the serogroup of <it>Shigella </it>most frequently responsible for sporadic and epidemic enteritis in developed countries. In recent years the emergence and spread of <it>S. sonnei </it>biotype g carrying class 2 integron have been frequently reported in many countries. Recently, <it>S. sonnei </it>has been reported as the prevalent serogroup of <it>Shigella </it>in Iran.</p> <p>The present study was carried out to investigate phenotypic and genetic characteristics of <it>Shigella sonnei </it>isolates identified in the years 2002 and 2003 in Tehran, Iran.</p> <p>Methods</p> <p>Biotyping, drug susceptibility testing, pulsed field gel electrophoresis (PFGE) and analysis of class 2 integrons have been carried out on 60 <it>S. sonnei </it>isolates, including 57 sporadic isolates from paediatric cases of shigellosis occurring in 2002 and 2003, two sporadic isolates recovered in 1984 and the ATCC 9290 strain.</p> <p>Results</p> <p>Biotype g and resistance to streptomycin, sulfamethoxazole-trimethoprim and tetracycline were exhibited by 54 of the 57 recent isolates. Of the 54 biotype g isolates, 28 exhibited a class 2 integron of 2161 bp, and 24 a class 2 integron of 1371 bp, respectively. Class 2 integrons were not detected in four isolates only, including the two endemic isolates recovered in 1984 and two strains from recent sporadic cases. PFGE divided the strains into eight pulsotypes labeled A to H, three major pulsotypes – A to C – including the large majority of the recent sporadic <it>S. sonnei </it>isolates. Pulsotypes A and C were the most prevalent groups, accounting for 41.6% and 35.0%, respectively, of the isolates under study.</p> <p>Conclusion</p> <p>The results suggest that biotype g, class 2 integron carrying <it>S. sonnei </it>are prevalent in our geographic area. <it>S. sonnei </it>isolated in the years 2002 and 2003 could be attributed to a few predominant clusters including, respectively, strains with pulsotypes B and C carrying a 2161 bp class 2 integron, and those having pulsotype A and a 1371 bp class 2 integron. A few epidemic clones are responsible for the apparently endemic occurrence of shigellosis in Tehran, Iran.</p
Constraints on cosmic strings using data from the first Advanced LIGO observing run
Cosmic strings are topological defects which can be formed in grand unified theory scale phase transitions in the early universe. They are also predicted to form in the context of string theory. The main mechanism for a network of Nambu-Goto cosmic strings to lose energy is through the production of loops and the subsequent emission of gravitational waves, thus offering an experimental signature for the existence of cosmic strings. Here we report on the analysis conducted to specifically search for gravitational-wave bursts from cosmic string loops in the data of Advanced LIGO 2015-2016 observing run (O1). No evidence of such signals was found in the data, and as a result we set upper limits on the cosmic string parameters for three recent loop distribution models. In this paper, we initially derive constraints on the string tension Gμ and the intercommutation probability, using not only the burst analysis performed on the O1 data set but also results from the previously published LIGO stochastic O1 analysis, pulsar timing arrays, cosmic microwave background and big-bang nucleosynthesis experiments. We show that these data sets are complementary in that they probe gravitational waves produced by cosmic string loops during very different epochs. Finally, we show that the data sets exclude large parts of the parameter space of the three loop distribution models we consider
Directional Limits on Persistent Gravitational Waves from Advanced LIGO’s First Observing Run
We employ gravitational-wave radiometry to map the stochastic gravitational wave background
expected from a variety of contributing mechanisms and test the assumption of isotropy using data
from the Advanced Laser Interferometer Gravitational Wave Observatory’s (aLIGO) first observing run.
We also search for persistent gravitational waves from point sources with only minimal assumptions
over the 20–1726 Hz frequency band. Finding no evidence of gravitational waves from either point
sources or a stochastic background, we set limits at 90% confidence. For broadband point sources, we
report upper limits on the gravitational wave energy flux per unit frequency in the range Fα;ΘðfÞ <
ð0.1–56Þ × 10−8 erg cm−2 s−1 Hz−1ðf=25 HzÞα−1 depending on the sky location Θ and the spectral
power index α. For extended sources, we report upper limits on the fractional gravitational wave energy
density required to close the Universe of Ωðf; ΘÞ < ð0.39–7.6Þ × 10−8 sr−1ðf=25 HzÞα depending on Θ
and α. Directed searches for narrowband gravitational waves from astrophysically interesting objects
(Scorpius X-1, Supernova 1987 A, and the Galactic Center) yield median frequency-dependent limits on
strain amplitude of h0 < ð6.7; 5.5; and 7.0Þ × 10−25, respectively, at the most sensitive detector frequencies
between 130–175 Hz. This represents a mean improvement of a factor of 2 across the band compared
to previous searches of this kind for these sky locations, considering the different quantities of strain
constrained in each case
Search for post-merger gravitational waves from the remnant of the binary neutron star merger GW170817
The first observation of a binary neutron star (NS) coalescence by the Advanced LIGO and Advanced Virgo gravitational-wave (GW) detectors offers an unprecedented opportunity to study matter under the most extreme conditions. After such a merger, a compact remnant is left over whose nature depends primarily on the masses of the inspiraling objects and on the equation of state of nuclear matter. This could be either a black hole (BH) or an NS, with the latter being either long-lived or too massive for stability implying delayed collapse to a BH. Here, we present a search for GWs from the remnant of the binary NS merger GW170817 using data from Advanced LIGO and Advanced Virgo. We search for short- (≲1 s) and intermediate-duration (≲500 s) signals, which include GW emission from a hypermassive NS or supramassive NS, respectively. We find no signal from the post-merger remnant. Our derived strain upper limits are more than an order of magnitude larger than those predicted by most models. For short signals, our best upper limit on the root sum square of the GW strain emitted from 1-4 kHz is at 50% detection efficiency. For intermediate-duration signals, our best upper limit at 50% detection efficiency is for a millisecond magnetar model, and for a bar-mode model. These results indicate that post-merger emission from a similar event may be detectable when advanced detectors reach design sensitivity or with next-generation detectors.</p
Full band all-sky search for periodic gravitational waves in the O1 LIGO data
We report on a new all-sky search for periodic gravitational waves in the frequency band 475–2000 Hz and with a frequency time derivative in the range of ½−1.0; þ0.1 × 10−8 Hz=s. Potential signals could be produced by a nearby spinning and slightly nonaxisymmetric isolated neutron star in our Galaxy. This search uses the data from Advanced LIGO’s first observational run O1. No gravitational-wave signals were observed, and upper limits were placed on their strengths. For completeness, results from the separately published low-frequency search 20–475 Hz are included as well. Our lowest upper limit on worst-case (linearly polarized) strain amplitude h0 is ∼4 × 10−25 near 170 Hz, while at the high end of our frequency range, we achieve a worst-case upper limit of 1.3 × 10−24. For a circularly polarized source (most favorable orientation), the smallest upper limit obtained is ∼1.5 × 10−25
Prospects for observing and localizing gravitational-wave transients with Advanced LIGO, Advanced Virgo and KAGRA
We present possible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next decade, with the intention of providing information to the astronomy community to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals, and study the capability of the network to determine the sky location of the source. We report our findings for gravitational-wave transients, with particular focus on gravitational-wave signals from the inspiral of binary neutron star systems, which are the most promising targets for multi-messenger astronomy. The ability to localize the sources of the detected signals depends on the geographical distribution of the detectors and their relative sensitivity, and 90% credible regions can be as large as thousands of square degrees when only two sensitive detectors are operational. Determining the sky position of a significant fraction of detected signals to areas of 5– 20 deg2 requires at least three detectors of sensitivity within a factor of ∼2 of each other and with a broad frequency bandwidth. When all detectors, including KAGRA and the third LIGO detector in India, reach design sensitivity, a significant fraction of gravitational-wave signals will be localized to a few square degrees by gravitational-wave observations alone
A unified approach to molecular epidemiology investigations: tools and patterns in California as a case study for endemic shigellosis
<p>Abstract</p> <p>Background</p> <p>Shigellosis causes diarrheal disease in humans from both developed and developing countries, and multi-drug resistance is an emerging problem. The objective of this study is to present a unified approach that can be used to characterize endemic and outbreak patterns of shigellosis using use a suite of epidemiologic and molecular techniques. The approach is applied to a California case study example of endemic shigellosis at the population level.</p> <p>Methods</p> <p>Epidemiologic patterns were evaluated with respect to demographics, multi-drug resistance, antimicrobial resistance genes, plasmid profiles, and pulsed-field gel electrophoresis (PFGE) fingerprints for the 43 <it>Shigella </it>isolates obtained by the Monterey region health departments over the two year period from 2004-2005.</p> <p>Results</p> <p>The traditional epidemiologic as well as molecular epidemiologic findings were consistent with endemic as compared to outbreak shigellosis in this population. A steady low level of cases was observed throughout the study period and high diversity was observed among strains. In contrast to most studies in developed countries, the predominant species was <it>Shigella flexneri </it>(51%) followed closely by <it>S. sonnei </it>(49%). Over 95% of <it>Shigella </it>isolates were fully resistant to three or more antimicrobial drug subclasses, and 38% of isolates were resistant to five or more subclasses. More than half of <it>Shigella </it>strains tested carried the <it>tetB</it>, <it>catA</it>, or <it>bla</it><sub>TEM </sub>genes for antimicrobial resistance to tetracycline, chloramphenicol, and ampicillin, respectively.</p> <p>Conclusion</p> <p>This study shows how epidemiologic patterns at the host and bacterial population levels can be used to investigate endemic as compared to outbreak patterns of shigellosis in a community. Information gathered as part of such investigations will be instrumental in identifying emerging antimicrobial resistance, for developing treatment guidelines appropriate for that community, and to provide baseline data with which to compare outbreak strains in the future.</p
The Complexities of 'Home': Young people 'on the move' and state responses
'Home’ invokes ambiguous meanings for social policy; issues of safety within and beyond the home are recurring themes in criminological research and literature as well as policy and practice-based interventions. These concepts are further complicated when consideration is given to the experiences of young people who run away or go missing from the family home or alternative care. Drawing on an extensive body of research and rigorous analysis of ‘home’ in this context, the paper considers how gendered and classed youth identities affect responses and interventions. By ‘problematizing’ the universalised concept of home and the notion of ‘family’ that it implies, this paper makes an original contribution to theoretical aspects of running away and youth journeys, engaging with issues of space, place and relations of exclusion, subordination and domination in relation to family and state powers and responsibilities. Journeys from home are, interchangeably, escape routes and dangerous endeavours, but can also denote acts of resistance and quests for emancipation
GWTC-1: A Gravitational-Wave Transient Catalog of Compact Binary Mergers Observed by LIGO and Virgo during the First and Second Observing Runs
We present the results from three gravitational-wave searches for coalescing compact binaries with component masses above 1 M⊙ during the first and second observing runs of the advanced gravitational-wave detector network. During the first observing run (O1), from September 12, 2015 to January 19, 2016, gravitational waves from three binary black hole mergers were detected. The second observing run (O2), which ran from November 30, 2016 to August 25, 2017, saw the first detection of gravitational waves from a binary neutron star inspiral, in addition to the observation of gravitational waves from a total of seven binary black hole mergers, four of which we report here for the first time: GW170729, GW170809, GW170818, and GW170823. For all significant gravitational-wave events, we provide estimates of the source properties. The detected binary black holes have total masses between 18.6−0.7+3.2 M⊙ and 84.4−11.1+15.8 M⊙ and range in distance between 320−110+120 and 2840−1360+1400 Mpc. No neutron star-black hole mergers were detected. In addition to highly significant gravitational-wave events, we also provide a list of marginal event candidates with an estimated false-alarm rate less than 1 per 30 days. From these results over the first two observing runs, which include approximately one gravitational-wave detection per 15 days of data searched, we infer merger rates at the 90% confidence intervals of 110−3840 Gpc−3 y−1 for binary neutron stars and 9.7−101 Gpc−3 y−1 for binary black holes assuming fixed population distributions and determine a neutron star-black hole merger rate 90% upper limit of 610 Gpc−3 y−1
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