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An ethnography of the Mongolian capital city of Ulaanbaatar during the nation's transition from socialism to a market-based economic system. Urban Hunters is an ethnography of the Mongolian capital city, Ulaanbaatar, during the nation's transition from socialism to a market-based economic system. Following the Soviet Union's collapse in 1991, Mongolia entered a period of economic chaos characterized by wild inflation, disappearing banks, and closing farms, factories, and schools. During this time of widespread poverty, a generation of young adults came of age. In exploring the social, cultural, and existential ramifications of a transition that has become permanent and acquired a logic of its own, Lars Hojer and Morten Axel Pedersen present a new theorization of social agency in postsocialist as well as postcolonial contexts.

Glioblastomas (GBMs) are aggressive brain tumors that always recur after radiotherapy. Cystine, mainly provided by the system X c − antiporter, is a requirement for glioma cell synthesis of glutathione (GSH) which has a critical role in scavenging free radicals, for example, after radiotherapy. Thus, we hypothesized that the X c − -inhibitor sulfasalazine (SAS) could potentiate the efficacy of radiotherapy against gliomas. Here, we show that the catalytic subunit of system X c − , xCT, was uniformly expressed in a panel of 30 human GBM biopsies. SAS treatment significantly reduced cystine uptake and GSH levels, whereas it significantly increased the levels of reactive oxygen species (ROS) in glioma cells in vitro . Furthermore, SAS and radiation synergistically increased DNA double-strand breaks and increased glioma cell death, whereas adding the antioxidant N-acetyl-L-cysteine (NAC) reversed cell death. Moreover, SAS and gamma knife radiosurgery (GKRS) synergistically prolonged survival in nude rats harboring human GBM xenografts, compared with controls or either treatment alone. In conclusion, SAS effectively blocks cystine uptake in glioma cells in vitro , leading to GSH depletion and increased ROS levels, DNA damage and cell death. Moreover, it potentiates the anti-tumor efficacy of GKRS in rats with human GBM xenografts, providing a survival benefit. Thus, SAS may have a role as a radiosensitizer to enhance the efficacy of current radiotherapies for glioma patients.

The proportion of births via cesarean section (CS) varies worldwide and in many countries exceeds WHO-recommended rates. Long-term health outcomes for children born by CS are poorly understood, but limited data suggest that CS is associated with increased infection-related hospitalisation. We investigated the relationship between mode of birth and childhood infection-related hospitalisation in high-income countries with varying CS rates. We conducted a multicountry population-based cohort study of all recorded singleton live births from January 1, 1996 to December 31, 2015 using record-linked birth and hospitalisation data from Denmark, Scotland, England, and Australia (New South Wales and Western Australia). Birth years within the date range varied by site, but data were available from at least 2001 to 2010 for each site. Mode of birth was categorised as vaginal or CS (emergency/elective). Infection-related hospitalisations (overall and by clinical type) occurring after the birth-related discharge date were identified in children until 5 years of age by primary/secondary International Classification of Diseases, 10th Revision (ICD-10) diagnosis codes. Analysis used Cox regression models, adjusting for maternal factors, birth parameters, and socioeconomic status, with results pooled using meta-analysis. In total, 7,174,787 live recorded births were included. Of these, 1,681,966 (23%, range by jurisdiction 17%-29%) were by CS, of which 727,755 (43%, range 38%-57%) were elective. A total of 1,502,537 offspring (21%) had at least 1 infection-related hospitalisation. Compared to vaginally born children, risk of infection was greater among CS-born children (hazard ratio (HR) from random effects model, HR 1.10, 95% confidence interval (CI) 1.09-1.12, p < 0.001). The risk was higher following both elective (HR 1.13, 95% CI 1.12-1.13, p < 0.001) and emergency CS (HR 1.09, 95% CI 1.06-1.12, p < 0.001). Increased risks persisted to 5 years and were highest for respiratory, gastrointestinal, and viral infections. Findings were comparable in prespecified subanalyses of children born to mothers at low obstetric risk and unchanged in sensitivity analyses. Limitations include site-specific and longitudinal variations in clinical practice and in the definition and availability of some data. Data on postnatal factors were not available. In this study, we observed a consistent association between birth by CS and infection-related hospitalisation in early childhood. Notwithstanding the limitations of observational data, the associations may reflect differences in early microbial exposure by mode of birth, which should be investigated by mechanistic studies. If our findings are confirmed, they could inform efforts to reduce elective CS rates that are not clinically indicated.

Ambient seismic noise correlations are widely used for high-resolution surface-wave imaging of Earth's lithosphere. Similar observations of the seismic body waves that propagate through the interior of Earth would provide a window into the deep Earth. We report the observation of the mantle transition zone through noise correlations of P waves as they are reflected by the discontinuities associated with the top [410 kilometers (km)] and the bottom (660 km) of this zone. Our data demonstrate that high-resolution mapping of the mantle transition zone is possible without using earthquake sources.

Lung cancer screening with low-dose CT can save lives. This European Union (EU) position statement presents the available evidence and the major issues that need to be addressed to ensure the successful implementation of low-dose CT lung cancer screening in Europe. This statement identified specific actions required by the European lung cancer screening community to adopt before the implementation of low-dose CT lung cancer screening. This position statement recommends the following actions: a risk stratification approach should be used for future lung cancer low-dose CT programmes; that individuals who enter screening programmes should be provided with information on the benefits and harms of screening, and smoking cessation should be offered to all current smokers; that management of detected solid nodules should use semi-automatically measured volume and volume-doubling time; that national quality assurance boards should be set up to oversee technical standards; that a lung nodule management pathway should be established and incorporated into clinical practice with a tailored screening approach; that non-calcified baseline lung nodules greater than 300 mm3, and new lung nodules greater than 200 mm3, should be managed in multidisciplinary teams according to this EU position statement recommendations to ensure that patients receive the most appropriate treatment; and planning for implementation of low-dose CT screening should start throughout Europe as soon as possible. European countries need to set a timeline for implementing lung cancer screening.

Fully mycoheterotrophic plants derive carbon and other nutrients from root-associated fungi and have lost the ability to photosynthesize. While mycoheterotroph plastomes are often degraded compared with green plants, the effect of this unusual symbiosis on mitochondrial genome evolution is unknown. By providing the first complete organelle genome data from Polygalaceae, one of only three eudicot families that developed mycoheterotrophy, we explore how both organellar genomes evolved after loss of photosynthesis. We sequenced and assembled four complete plastid genomes and a mitochondrial genome from species of Polygalaceae, focusing on non-photosynthetic Epirixanthes. We compared these genomes with those of other mycoheterotroph and parasitic plant lineages, and assessed whether organelle genes in Epirixanthes experienced relaxed or intensified selection compared with autotrophic relatives. Plastomes of two species of Epirixanthes have become substantially degraded compared with that of autotrophic Polygala. Although the lack of photosynthesis is presumably homologous in the genus, the surveyed Epirixanthes species have marked differences in terms of plastome size, structural rearrangements, gene content and substitution rates. Remarkably, both apparently replaced a canonical plastid inverted repeat with large directly repeated sequences. The mitogenome of E. elongata incorporated a considerable number of fossilized plastid genes, by intracellular transfer from an ancestor with a less degraded plastome. Both plastid and mitochondrial genes in E. elongata have increased substitution rates, but the plastid genes of E. pallida do not. Despite this, both species have similar selection patterns operating on plastid housekeeping genes. Plastome evolution largely fits with patterns of gene degradation seen in other heterotrophic plants, but includes highly unusual directly duplicated regions. The causes of rate elevation in the sequenced Epirixanthes mitogenome and of rate differences in plastomes of related mycoheterotrophic species are not currently understood.

We study the nature of sovereign credit risk using an extensive set of sovereign CDS data. We find that the majority of sovereign credit risk can be linked to global factors. A single principal component accounts for 64 percent of the variation in sovereign credit spreads. Furthermore, sovereign credit spreads are more related to the US stock and high-yield markets than they are to local economic measures. We decompose credit spreads into their risk premium and default risk components. On average, the risk premium represents about a third of the credit spread.

Flash memories are essential for modern electronics; here a selenium-templated polyoxometalate is used to engineer new metal–oxide–semiconductor devices. Flash memory goes molecular Flash memory is becoming standard for smart phones, cameras, memory sticks and other devices. Its achievable data storage densities are ultimately limited by the minimum size of the individual data cells that can be fabricated, so molecule-based flash memory is an attractive proposition for stretching these limits. Christoph Busche and colleagues report the design, synthesis and electronic characterization of a family of metal-oxide cluster molecules that are compatible with current technology. The new materials are highly configurable at the atomic-level and show promise for implementation in practical devices. Flash memory devices—that is, non-volatile computer storage media that can be electrically erased and reprogrammed—are vital for portable electronics, but the scaling down of metal–oxide–semiconductor (MOS) flash memory to sizes of below ten nanometres per data cell presents challenges. Molecules have been proposed to replace MOS flash memory 1 , but they suffer from low electrical conductivity, high resistance, low device yield, and finite thermal stability, limiting their integration into current MOS technologies. Although great advances have been made in the pursuit of molecule-based flash memory 2 , there are a number of significant barriers to the realization of devices using conventional MOS technologies 3 , 4 , 5 , 6 , 7 . Here we show that core–shell polyoxometalate (POM) molecules 8 can act as candidate storage nodes for MOS flash memory. Realistic, industry-standard device simulations validate our approach at the nanometre scale, where the device performance is determined mainly by the number of molecules in the storage media and not by their position. To exploit the nature of the core–shell POM clusters, we show, at both the molecular and device level, that embedding [(Se( iv )O 3 ) 2 ] 4− as an oxidizable dopant in the cluster core allows the oxidation of the molecule to a [Se( v ) 2 O 6 ] 2− moiety containing a {Se( v )–Se( v )} bond (where curly brackets indicate a moiety, not a molecule) and reveals a new 5+ oxidation state for selenium. This new oxidation state can be observed at the device level, resulting in a new type of memory, which we call ‘write-once-erase’. Taken together, these results show that POMs have the potential to be used as a realistic nanoscale flash memory. Also, the configuration of the doped POM core may lead to new types of electrical behaviour 9 , 10 , 11 . This work suggests a route to the practical integration of configurable molecules in MOS technologies as the lithographic scales approach the molecular limit 12 .

We have developed a fluorescence-based fiber-optical biosensor, which can selectively detect different antibodies in serial at preselected positions inside a single piece of fiber. The fiber is a microstructured polymer optical fiber fabricated from TOPAS cyclic olefin copolymer, which allows for UV activation of localized sensor layers inside the holes of the fiber. Serial fluorescence-based selective sensing of Cy3-labelled α-streptavidin and Cy5-labelled α-CRP antibodies is demonstrated.

Hydrothermal liquefaction (HTL) is a promising technology for the production of bio-crude. However, some unresolved issues still exist within HTL, which need to be resolved before its promotion on a commercial scale. The management of the aqueous phase is one of the leading challenges related to HTL. In this study, the sewage sludge has been liquefied at 350 °C with and without catalyst (K2CO3). Subsequently, aqueous phase recycling was applied to investigate the effect of recycling on bio-crude properties. Obtained results showed that the energy recovery in the form of bio-crude increased by 50% via aqueous phase recirculation, whereas nitrogen content in the bio-crude was approximately doubled after eight rounds of recycling. GCMS characterization of the aqueous phase indicated acetic acid as a major water-soluble compound, which employed as a catalyst (0.56 M), and resulted in a negligible increase in bio-crude yield. ICP-AES highlighted that the majority of the inorganics were transferred to the solid phase, while the higher accumulation of potassium and sodium was found in the aqueous phase via successive rounds of recycling.