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We observed pediatric S. aureus hospitalizations decreased 36% from 26.3 to 16.8 infections per 1,000 admissions from 2009 to 2016, with methicillin-resistant S. aureus (MRSA) decreasing by 52% and methicillin-susceptible S. aureus decreasing by 17%, among 39 pediatric hospitals. Similar decreases were observed for days of therapy of anti-MRSA antibiotics.
The 13-valent pneumococcal conjugate vaccine (PCV) has been part of routine immunisation in a 2 + 1 schedule (two primary infant doses and one booster during the second year of life) in the UK since 2010. Recently, the UK's Joint Committee on Vaccination and Immunisation recommended changing to a 1 + 1 schedule while conceding that this will increase disease burden; however, uncertainty remains on how much pneumococcal burden – including invasive pneumococcal disease (IPD) and non-invasive disease – will increase. We built a dynamic transmission model to investigate this question. The model predicted that a 1 + 1 schedule would incur 8777–27 807 additional cases of disease and 241–743 more deaths over 5 years. Serotype 19A caused 55–71% of incremental IPD cases. Scenario analyses showed that booster dose adherence, effectiveness against carriage and waning in a 1 + 1 schedule had the most influence on resurgence of disease. Based on the model assumptions, switching to a 1 + 1 schedule will substantially increase disease burden. The results likely are conservative since they are based on relatively low vaccine-type pneumococcal transmission, a paradigm that has been called into question by data demonstrating an increase of IPD due to several vaccine serotypes during the last surveillance year available.
In this study, we identify the linguistic and social predictors that condition onset /s/ weakening in speech data from sociolinguistic interviews with 72 Salvadoran Spanish speakers. In addition, we compare and contrast the explanatory power of instrumental and traditional segmental approaches. We find that the instrumental approach, which identifies flanking segments, stress, and region of origin of the speaker as conditioners of onset /s/ shortening and lowering of center of gravity, does not account for observed social variation in the data. Contrastingly, an ordinal logistic regression based on a combination of instrumental measures and perceived phonetic categories identifies flanking segment, region of origin, sex, and age of the speaker as predictors of onset /s/ weakening. We conclude that an exclusively instrumental analysis examining variation of onset /s/ thus obscures the potential social meaning of onset /s/ weakening in El Salvador.
We report the discovery of widespread millimeter-wavelength Class I methanol maser emission associated with protostellar molecular outflows in the massive (proto)cluster G11.92−0.61. Our ~0.5″-resolution SMA and ALMA observations of the 229 GHz and 278 GHz Class I transitions reveal seven and twelve candidate masers, respectively: all 229 GHz masers have 278 GHz counterparts, and five are also coincident with 44 GHz Class I masers previously detected with the VLA. For paired masers, the peak intensities at 229 GHz and 278 GHz are correlated. We also find tentative evidence for a correlation between the strength of millimeter-wavelength Class I maser emission and the energy of the associated molecular outflow.
We present Kitty, an unprecedented and near simultaneous flaring event in ten transitions (6 hydroxyl, 1 water and 3 methanol), that began on 1 January 2015 in the massive star-forming region NGC6334F located in the Cat’s Paw Nebula. The brightest components in each transition increased by factors of 20 to 70 in line with a factor of ~70 increase in dust emission luminosity for the source MM1. We also report the detection of only the fifth known 4.660 GHz hydroxyl maser and that it varied in a correlated fashion with 1.720, 6.031, and 6.035 GHz hydroxyl counterparts. We postulate that if Kitty, and two historical flares in 1965 & 1999, are accretion events and are caused by the successive passages of a secondary star disrupting the accretion disk, where the frequency of occurrence is cycling down at a rate of ~2.2, it is possible another event will occur in 2022.
Our 2015-2016 ALMA 1.3 to 0.87 mm observations (resolution ~200 au) of the massive protocluster NGC6334I revealed that an extraordinary outburst had occurred in the dominant millimeter dust core MM1 (luminosity increase of 70×) when compared with earlier SMA data. The outburst was accompanied by the flaring of ten maser transitions of three species. We present new results from our recent JVLA observations of Class II 6.7 GHz methanol masers and 6 GHz excited OH masers in this region. Class II masers had not previously been detected toward MM1 in any interferometric observations recorded over the past 30 years that targeted the bright masers toward other members of the protocluster (MM2 and MM3=NGC6334F). Methanol masers now appear both toward and adjacent to MM1 with the strongest spots located in a dust cavity ~1 arcsec (1300 au) north of the MM1B hypercompact HII region. In addition, new excited OH masers appear on the non-thermal source CM2. These data reveal the dramatic effects of episodic accretion onto a deeply-embedded high mass protostar and demonstrate its ongoing impact on the surrounding protocluster.
We present subarcsecond resolution pre- and post-outburst JVLA continuum and water maser observations of the massive protostellar outburst source NGC6334I-MM1. The continuum data at 5 and 1.4 cm reveal that the free-free emission powered by MM1B, modeled as a hypercompact HII region from our 2011 JVLA data, has dropped by a factor of 5.4. Additionally, the water maser emission toward MM1, which had previously been strong (500 Jy) has dramatically reduced. In contrast, the water masers in other locations in the protocluster have flared, with the strongest spots associated with CM2, a non-thermal radio source that appears to mark a shock in a jet emanating 2″ (2600 au) northward from MM1. The observed quenching of the HCHII region suggests a reduction in uv photon production due to bloating of the protostar in response to the episodic accretion event.
Supernovae have a profound effect on the morphology, kinematics, and metallicity of galaxies. The impact of supernova shocks on surrounding molecular clouds is also thought to trigger new generations of star formation. A critical ingredient in such interactions and, indeed, all aspects of supernova remnant (SNR) evolution are magnetic fields. In recent years, OH (1720 MHz) masers have been used as signposts for the interaction of SNRs with molecular gas. In addition to tracing SNR/molecular cloud interactions, the OH (1720 MHz) maser line also provides a unique opportunity to measure the strength of the post-shock magnetic field via Zeeman splitting. Recent results from efforts to both detect the magnetic fields and resolve the maser spot sizes of OH (1720 MHz) masers toward W51C using the VLBA and W44 using MERLIN are presented. These observations have yielded magnetic field detections between 0.5 and 2.5 mG and large maser spot sizes of about 1015 cm.
The availability of high spatial resolution molecular gas observations from ALMA, and similar resolution observations in the radio continuum using the VLA, is providing the opportunity to make comparisons with specific features seen in optical observations more directly than in the past. Using our ALMA observations of the Antennae galaxies as a springboard, we have compared the locations of small-scale CO (3−2) features with a variety of multi-wavelength observations, in particular optical and near-infrared imaging using both broad (UBVI) and narrow-band data (Hα and Paβ) taken with the HST, and radio (3.6 cm) continuum observations taken with the VLA. This comparison leads to the development of an evolutionary classification system which provides a framework for studying the sequence of star cluster formation and evolution, from diffuse Giant Molecular Clouds (GMCs), to proto, embedded, emerging, young, and intermediate/old star clusters. Using this evolutionary framework, we estimate the maximum age range of clusters formed in a single GMC is approximately 10 Myr. This suggests that the molecular gas is removed over this timescale, resulting in the cessation of star formation and the destruction of the GMC within a radius of about 200 pc.
Misurata is the second city of Western Libya (Tripolitania) and, with its surrounding farms and villages, had some 83,000 inhabitants in the early nineteen-sixties, but has grown rapidly since then. West of the city is a narrow but fertile plain coming from Zliten between the dune-encumbered coastal ridge and a line of low hills which are the last eastward vestiges of the Tripolitanian Jebel and which come to an end shortly before Misurata. Twelve kilometres to the east, at Gasr Ahmed, the coast turns south-eastwards to form the western side of the Greater Syrtis, or Gulf of Sidra. Between Misurata and Gasr Ahmed the cultivated area narrows to become a kind of peninsula between the coast and the marshes of the Sebkha Taworga which are extensively flooded during the winter. South of Misurata, along the main road to Fezzan and Cyrenaica, the country becomes increasingly arid. East of the road cultivation soon gives place to mud flats and salt marshes, the successive sebkhas Taworga, Hishah and Al Awenat, which together cover an area some hundred kilometres long and twenty broad.
The name Misurata (Misratah) is Berber and did not come into the district until the tribal movements in late antiquity, when the Hawara spread into Eastern Tripolitania. According to tradition the Berber hero Aurigh had four sons, Calden, Meld, Hawar and Maggher. All their descendants came to be designated collectively as the children of Hawar, and among these were Wurfel and Misratah, sons of Meld. The sons of Wurfel have dwelt ever since in and to the south of Beni Ulid, and the Misratah have occupied the coastlands to the northeast. Ibn Batuta mentions passing through the country of the Misratah in 1326. Ibn Khaldun says that in his days (14th century) the Misratah were very powerful and only paid a very small tribute to the Arabs, ‘tribute which they have the air of handing over by condescension.’ He says ‘they occupy themselves by commerce, and travel frequently to Egypt and Alexandria, to southern Tunisia and to Fezzan.’ The inhabitants of the Misurata area to-day include groups of Berber origin mixed with the descendants of the first Arabs who came into Tripolitania; others, descended from Turkish immigrants; and yet others claiming Sherifian origin, that is, descent from the Prophet Mohamed himself.
The 1971 Expedition was in the field for almost a month over Easter, thanks to the continued kindness and good will of the Libyan Department of Antiquities, and further generous financial support from the British Academy, the Seven Pillars of Wisdom Trust, the Society for Libyan Studies and the University of Newcastle.
The site of Saniat Gebril lies 300 yards east of the abandoned mud-brick town of Germa. Trial trenching (1965) and surface sherding had shown that at least 5 acres of compact settlement existed there, with the strong likelihood that more sparsely-placed buildings stretched as far as Germa. From the previous work it was thought that the main settlement consisted of a series of smallish mud-brick buildings, occupied from the late-first century A.D. until the early-third century, when the site was abandoned and not subsequently re-occupied.
In the Gebel Garian, about 20 kilometres south of Asabaa, the map-makers of 1964 indicated an ancient wall (Fig. 1) called Hadd Hajar (i.e. wall of stone) running south-west for six kilometres from Ras al Tays al Abyad (858 m; the Hill of the White Goat) on which stood a watch tower, to Ras al Said (764 m). The country crossed by Hadd Hajar is about 690-730 m above sea-level with a gently-undulating surface constituting a fairly open and level valley. The hills are covered with esparto-grass. On the west the Wadi Wamis winds among closely-set hills while, in the north-east, the wall is carried for a further three quarters of a kilometre across a narrow valley from Ras al Tays al Abyad to another hill Ras al Saqifah. An old track comes southwards down this valley flanked on the east side by a barrier of hills over 800 m high. Where the track crosses the wall there is a Roman building (Gasr al Saqifah) with traces of an archway for people and flocks to pass through. Two kilometres to the south is an old cistern (Majin Saqifah) presumably Roman. Beyond, the track continues about 25 kilometres to a large well, Bir al Shaqaykah (Sceghega), after which it is another 28 kilometres south-eastwards to Mizdah on the Wadi Sofeggin.
Antimicrobial stewardship programs (ASPs) are a mechanism to ensure the appropriate use of antimicrobials. The extent to which ASPs are formally implemented in freestanding children's hospitals is unknown. The objective of this study was to determine the prevalence and characteristics of ASPs in freestanding children's hospitals.
We conducted an electronic survey of 42 freestanding children's hospitals that are members of the Children's Hospital Association to determine the presence and characteristics of their ASPs. For hospitals without an ASP, we determined whether stewardship strategies were in place and whether there were barriers to implementing a formal ASP.
We received responses from 38 (91%) of 42. Among responding institutions, 16 (38%) had a formal ASP, and 15 (36%) were in the process of implementing a program. Most ASPs (13 [81%] of 16) were started after 2007. The median number of full-time equivalents dedicated to ASPs was 0.63 (range, 0.1–1.8). The most common antimicrobials monitored by ASPs were linezolid, vancomycin, and carbapenems. Many hospitals without a formal ASP were performing stewardship activities, including elements of prospective audit and feedback (9 [41%] of 22), formulary restriction (9 [41%] of 22), and use of clinical guidelines (17 [77%] of 22). Antimicrobial outcomes were more likely to be monitored by hospitals with ASPs (100% vs 68%; P = .01), although only 1 program provided support for a data analyst.
Most freestanding children's hospitals have implemented or are developing an ASP. These programs differ in structure and function, and more data are needed to identify program characteristics that have the greatest impact.
We analyze a high resolution (114″ × 60″) 74 MHz image of the Galactic center taken with the Very Large Array (VLA). We have identified several absorption and emission features in this region, and we discuss preliminary results of two Galactic center sources: the Sgr D complex (G1.1–0.1) and the Galactic center lobe (GCL).
The 74 MHz image displays the thermal and nonthermal components of Sgr D and we argue the Sgr D supernova remnant (SNR) is consistent with an interaction with a nearby molecular cloud and the location of the Sgr D Hii region on the near side of the Galactic center. The image also suggests that the emission from the eastern side of the GCL contains a mixture of both thermal and nonthermal sources, whereas the western side is primarily thermal.