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With the exception of Circum-Alpine wetland sites, structural remains of fourth-millennium BC settlements in Central Europe are rarely encountered. As a result, there is a dearth of information concerning settlement organisation and social differentiation. Recent excavations at the waterlogged Parkhaus Opéra site on the shores of Lake Zurich have, however, provided important new evidence for the existence of complex Late Neolithic settlement strategies and social stratification. Excellent organic preservation conditions permit extensive dendrochronological analyses of structures and the precise phasing of building activity. The results reveal a complex and highly dynamic settlement system, and provide a rare insight into the organisation of Late Neolithic Central European society.
Over the last decade, DNA origami has matured into one of the most powerful bottom-up nanofabrication techniques. It enables both the fabrication of nanoparticles of arbitrary two-dimensional or three-dimensional shapes, and the spatial organization of any DNA-linked nanomaterial, such as carbon nanotubes, quantum dots, or proteins at ∼5-nm resolution. While widely used within the DNA nanotechnology community, DNA origami has yet to be broadly applied in materials science and device physics, which now rely primarily on top-down nanofabrication. In this article, we first introduce DNA origami as a modular breadboard for nanomaterials and then present a brief survey of recent results demonstrating the unique capabilities created by the combination of DNA origami with existing top-down techniques. Emphasis is given to the open challenges associated with each method, and we suggest potential next steps drawing inspiration from recent work in materials science and device physics. Finally, we discuss some near-term applications made possible by the marriage of DNA origami and top-down nanofabrication.
We conducted a hospital-based cross-sectional study among children aged <5 years in Thi-Qar Governorate, south-eastern Iraq, in order to examine the prevalence, risk factors and antimicrobial resistance associated with gastroenteritis caused by Salmonella infection. From 320 diarrhoea cases enrolled between March and August 2016, 33 (10·3%, 95% confidence interval (CI) 8·4–12·4) cases were stool culture-positive for non-typhoidal Salmonella enterica. The most commonly identified serovar was Typhimurium (54%). Multivariable logistic regression analysis indicated that the odds of Salmonella infection in children from households supplied by pipe water was 4·7 (95% CI 1·6–13·9) times higher compared with those supplied with reverse osmosis treated water. Similarly, children from households with domestic animals were found to have a higher odds (OR 10·5; 95% CI 3·8–28·4) of being Salmonella stool culture-positive. The likelihood of Salmonella infection was higher (OR 3·9; 95% CI 1·0–6·4) among children belonging to caregiver with primary vs. tertiary education levels. Lower odds (OR 0·4; 95% CI 0·1–0·9) of Salmonella infection were associated with children exclusively breast fed as compared with those exclusively bottle fed. Salmonella infection was three times lower (95% CI 0·1–0·7) in children belonging to caregiver who reported always washing hands after cleaning children following defecation, vs. those belonging to caregivers who did not wash hands. The antimicrobial resistance profile by disc diffusion revealed that non-susceptibility to tetracycline (78·8%), azithromycin (66·7%) and ciprofloxacin (57·6%) were the most commonly seen, and 84·9% of Salmonella isolates were classified as multi-drug resistant. This is the first study on prevalence and antimicrobial resistance of Salmonella infection among children in this setting. This work provides specific epidemiological data which are crucial to understand and combat paediatric diarrhoea in Iraq.
Adequate nutrition is critical for optimal growth and development. However, young children may be at risk of nutrient deficiencies when transitioning to weaning foods for a variety of reasons. Supplementation with fortified milk may provide potentially lacking essential nutrients, but effects on growth and nutritional status are yet to be established.
Five databases were searched for randomised controlled trials using fortified milk against control milk in young children. Outcomes were growth, body composition and/or biochemical markers. Pooled differences in means were calculated for continuous outcomes and odds ratios for binary outcomes.
Randomised controlled trials set in any country.
Otherwise healthy children aged 6–47 months.
Fifteen articles met the eligibility criteria. Fortification varied from Fe, Zn, vitamins, essential fatty acids, to pre- and/or probiotics. Frequently reported outcomes were weight, height and Fe status. Studies varied in geographical location, sample size and duration. Fortified milk had minimal effects on weight gain (mean difference=0·17 kg; 95 % CI 0·02, 0·31 kg) compared with control milk. The risk of anaemia was reduced in fortified milk groups (OR=0·32; 95 % CI 0·15, 0·66) compared with control groups. There were no significant effects on height gain, changes in body composition or Hb concentration.
Fortified milk is an effective source of complementary nutrition to supplement children in need when consumed in appropriate amounts in addition to a normal diet. Due to compositional differences, further research on fortified milk is warranted before making global recommendations on benefits for growth and nutritional outcomes in young children.
X-ray emission observed from the SS433/W50 system has been interpreted as resulting from the interaction of the binary jets with the surrounding medium. We have been carrying out millimetre wavelength measurements of this system. We find no evidence for the association of a molecular cloud with the eastern jet, but we do find evidence for a strong association with the western jet.
What might the wreckage of a former prison in south Lebanon that was destroyed during Israeli bombardment in 2006 have in common with a series of “family-oriented” amusement parks built by a corporate investment group? How might these sites be related to an ecotourism facility high in the mountains above Saida and the 70-some cafés and restaurants that have opened in the southern suburbs of Beirut since 2000? Aside from being fieldsites in our ongoing research on Islam and leisure in Lebanon, these places are significant to the political party Hizbullah. They tell us something about the relationship of culture to politics in the Hizbullah community, and they can be considered part of a recently emergent “Islamic milieu” in Lebanon.
Recent research has indicated that learners exposed to second language words’ orthographic forms of words can often use this information to make inferences about the words’ phonological forms. Here we asked, do learners benefit even when the orthography is unfamiliar? We taught native English speakers minimal nonword pairs differentiated by the Arabic velar–uvular contrast (e.g., [kubu], [qubu]) and manipulated the quality of orthographic input. We found that participants were consistently unable to associate the novel phonemes with novel words. Results are discussed in terms of (a) the role of orthographic input in second language word form learning, (b) the influence of orthographic familiarity in moderating the role of orthographic input, and (c) the issue of talker variability in word learning.
Recently researchers have become increasingly interested in the influence of orthographic forms on second language (L2) phonology. Orthographic forms (or spellings) represent the sounds and words of a language in writing. L2 learners, in particular those in instructed settings, are simultaneously exposed to the orthographic forms and the phonological forms of the target language. Recent investigations have indicated that orthographic input can affect learners’ phonological development and word learning in their second language in various ways. The availability of L2 orthographic forms in the input to L2 learners can facilitate speech production, perception, and/or word form learning (Escudero, Hayes-Harb, & Mitterer, 2008; Showalter & Hayes-Harb, 2013). It can hinder targetlike acquisition (Bassetti, 2007; Hayes-Harb, Nicol, & Barker, 2010), or it can have mixed effects or no effect at all (Escudero & Wanrooij, 2010; Simon, Chamblessb, & Alvesc, 2010).
In situ imaging using (scanning) transmission electron microscopy has proven to be an extremely important and powerful cross-disciplinary scientific technique. In particular nanotechnology and materials sciences have special interest in assembly and disintegration processes, in growth and shape-tuning of (nano)-particles, and, furthermore in mechanistic studies of chemical reactions underlying these processes. However, limitations for in liquid and in situ imaging using electron microscopy arise from the stringent experimental conditions required with respect to electron scattering.
Here, we present a nanofluidic sample cell allowing for controlled fluidic conditions which preserve the highest possible spatial resolution for in-liquid electron microscopy. The nanocell allows for liquid flow with a flow control mechanism operated external to the microscope column enabling on-the-fly sample exchange within the imaging area. A well-defined flow path allows us to direct the motion of gold nanorods through fluid flow. Further a particle’s Brownian motion becomes evident once the external flow is terminated. In addition to quantitatively showing the resolution capabilities of our nanofluidic design, we show preliminary results of in situ imaging of gold nanorods and unstained amyloid fibrils to emphasize the significance of this imaging modality for both material sciences and biology.
We perform an XMM-Newton study of the mixed-morphology supernova remnant (MMSNR) W28. The X-ray spectrum arising from the northeastern shell consists of a thermal component plus a non-thermal power-law component with a hard photon index (~1.5). Non-thermal bremsstrahlung is the most favourible origin of the hard X-ray emission. The gas in the SNR interior is centrally peaked and best described by a two-temperature thermal model. We found a non-uniform absorption column density and temperature profile for the central gas, indicating that the remnant is evolving in a non-uniform environment with denser material in the east. We argue that the cloudlet evaporation is an indispensable process to explain both the spectral properties and the clumpiness in the X-ray emission.
We present the first detailed Chandra and XMM-Newton study of the young Galactic supernova remnant (SNR) Kes 73 associated with the anomalous X-ray pulsar (AXP) 1E 1841–045. Images of the remnant in the radio (20 cm), infrared (24 μm), and X-rays (0.5–7 keV) reveal a spherical morphology with a bright western limb. High-resolution Chandra images show bright diffuse emission across the remnant, with several small-scale clumpy and knotty structures filling the SNR interior. The overall Chandra and XMM-Newton spectrum of the SNR is best described by a two-component thermal model with the hard component characterized by a low ionization timescale, suggesting that the hot plasma has not yet reached ionization equilibrium. The soft component is characterized by enhanced metal abundances from Mg, Si, and S, suggesting the presence of metal-rich supernova ejecta. We discuss the explosion properties of the supernova and infer the mass of its progenitor star. Such studies shed light on our understanding of SNRs associated with highly magnetized neutron stars.
The 1968 discovery of the Crab and Vela pulsars in their respective supernova remnants (SNRs) confirmed Baade and Zwicky's 1934 prediction that supernovae form neutron stars. Observations of Pulsar Wind Nebulae (PWNe), particularly with the Chandra X-ray Observatory, have in the past decade opened a new window to focus on the neutron stars' relativistic winds, study their interaction with their hosting SNRs, and find previously missed pulsars. While the Crab has been thought for decades to represent the prototype of PWNe, we now know of different classes of neutron stars and PWNe whose properties differ from the Crab. In this talk, I review the current status of neutron stars/PWNe-SNRs associations, and highlight the growing diversity of PWNe with an X-ray eye on their association with highly magnetized neutron stars. I conclude with an outlook to future high-energy studies.
Motivated by the wealth of past, existing, and upcoming X-ray and gamma-ray missions, we have developed the first public database of high-energy observations of all known Galactic Supernova Remnants (SNRs): http://www.physics.umanitoba.ca/snr/SNRcat. The catalogue links to, and complements, other existing related catalogues, including Dave Green's radio SNRs catalogue. We here highlight the features of the high-energy catalogue, including allowing users to filter or sort data for various purposes. The catalogue is currently targeted to Galactic SNR observations with X-ray and gamma-ray missions, and is timely with the upcoming launch of X-ray missions (including Astro-H in 2014). We are currently developing the existing database to include an up-to-date Pulsar Wind Nebulae (PWNe)-dedicated webpage, with the goal to provide a global view of PWNe and their associated neutron stars/pulsars. This extensive database will be useful to both theorists to apply their models or design numerical simulations, and to observers to plan future observations or design new instruments. We welcome input and feedback from the SNR/PWN/neutron stars community.