A global three-dimensional (i.e. latitude, longitude, altitude) climatology of tropospheric ozone is derived from the ozone sounding record by trajectory mapping. Approximately 52 000 ozonesonde ...profiles from more than 100 stations worldwide since 1965 are used. The small number of stations results in a sparse geographical distribution. Here, forward and backward trajectory calculations are performed for each sounding to map ozone measurements to a number of other locations, and so to fill in the spatial domain. This is possible because the lifetime of ozone in the troposphere is of the order of weeks. This physically based interpolation method offers obvious advantages over typical statistical interpolation methods. The trajectory-mapped ozone values show reasonable agreement, where they overlap, to the actual soundings, and the patterns produced separately by forward and backward trajectory calculations are similar. Major regional features of the tropospheric ozone distribution are clearly evident in the global maps. An interpolation algorithm based on spherical functions is further used for smoothing and to fill in remaining data gaps. The resulting three-dimensional global tropospheric ozone climatology facilitates visualization and comparison of different years, decades, and seasons, and offers some intriguing insights into the global variation of tropospheric ozone. It will be useful for climate and air quality model initialization and validation, and as an a priori climatology for satellite data retrievals. Further division of the climatology into decadal and annual averages can provide a global view of tropospheric ozone changes, although uncertainties with regard to the performance of older sonde types, as well as more recent variations in operating procedures, need to be taken into account.
Highlights • Inter-hemispheric FC of the motor areas was compared between patients with BPAI and healthy controls. • BPAI decreases resting-state inter-hemispheric FC between the two M1 areas. • ...Decreased inter-hemispheric FC implies declined efficiency of information transfer and collaboration.
As agricultural land and freshwater inextricably interrelate and interact with each other, the conventional water and land policy in “silos” should give way to nexus thinking when formulating the ...land and water management strategies. This study constructs a systems multi-regional input-output (MRIO) model to expound global land-water nexus by simultaneously tracking agricultural land and freshwater use flows along the global supply chains. Furthermore, land productivity and irrigation water requirements of 160 crops in different regions are investigated to reflect the land-water linkage. Results show that developed economies (e.g., USA and Japan) and major large developing economies (e.g., mainland China and India) are the overriding drivers of agricultural land and freshwater use globally. In general, significant net transfers of these two resources are identified from resource-rich and less-developed economies to resource-poor and more-developed economies. For some crops, blue water productivity is inversely related to land productivity, indicating that irrigation water consumption is sometimes at odds with land use. The results could stimulus international cooperation for sustainable land and freshwater management targeting on original suppliers and final consumers along the global supply chains. Moreover, crop-specific land-water linkage could provide insights for trade-off decisions on minimizing the environmental impacts on local land and water resources.
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•Agricultural land and freshwater use within global supply chains are tracked simultaneously.•Land productivity and irrigation water requirements of 160 crops in different regions are investigated.•Approximately one-third of land use and water withdrawal is attributed to interregional trade.•Trade-off decisions should be made for both local agricultural production and global supply chain management.
Borides have been widely used in cast TiAl alloy for grain refinement and a variety of stoichiometry and crystal structure of borides were reported. Here the effects of alloying elements Nb, Ta, and ...Mn on the structural stability of fine boride precipitates in TiAl alloys have been studied combining transmission electron microscopy (TEM) and first-principles calculations. The results show that most boride particles have the TiB stoichiometry. In the alloy containing Nb and Mn, all the TiB particles have the B27 structure and are highly enriched with Nb but depleted with Mn. In the alloy containing Nb and Ta, however, the intergrowth of Bf and B27 structure has been observed, and the TiB particles are enriched with both Nb and Ta. First-principles calculations reveal different effects of Nb, Ta, and Mn on the structural stability of TiB polymorphs. Nb stabilizes B27 but destabilizes Bf. Ta strongly stabilizes both B27 and Bf structures. Mn strongly destabilizes both B27 and Bf structures.
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•The B27-type TiB in TiAl is enriched with Nb and Ta but depleted with Mn.•Nb stabilizes B27 but destabilizes Bf.•Ta strongly stabilizes both B27 and Bf structures.•Mn strongly destabilizes both B27 and Bf structures.•Atomic structure of the B27/Bf interface has been determined.
Pilocytic astrocytomas (PAs), WHO malignancy grade I, are the most frequently occurring central nervous system tumour in 5- to 19-year-olds. Recent reports have highlighted the importance of MAPK ...pathway activation in PAs, particularly through a tandem duplication leading to an oncogenic BRAF fusion gene. Here, we report two alternative mechanisms resulting in MAPK activation in PAs. Firstly, in striking similarity to the common BRAF fusion, tandem duplication at 3p25 was observed, which produces an in-frame oncogenic fusion between SRGAP3 and RAF1. This fusion includes the Raf1 kinase domain, and shows elevated kinase activity when compared with wild-type Raf1. Secondly, a novel 3 bp insertion at codon 598 in BRAF mimics the hotspot V600E mutation to produce a transforming, constitutively active BRaf kinase. Although these two alterations are not common, they bring the number of cases with an identified 'hit' on the Ras/Raf-signalling pathway to 36 from our series of 44 (82%), confirming its central importance to the development of pilocytic astrocytomas.
A mini-symposium was held in Montreal, Canada, at the International Surgical Week for the Breast Surgical International in 2007 addressing the question whether breast cancer is the same disease in ...Asian and Western countries. Numerous investigators from Asian and Western countries presented the epidemiologic and clinical outcome data of women with breast cancer. Although there are significant similarities, the striking difference is that the peak age for breast cancer is between 40 and 50 years in the Asian countries, whereas the peak age in the Western countries is between 60 and 70 years. Also, the incidence of breast cancer in Asia is rising and is associated with increased mortality. In the West, although the incidence is increasing, the mortality rate is definitely decreasing. Future prospective data collection from Asian and Western countries may provide further interesting epidemiologic and outcome data regarding the outcome of women with breast cancer from Asian and Western countries.
Background
Whether breast cancer is the same disease in Asian and Western countries was the topic of a 2007 Breast Surgery International symposium at International Surgical Week.
Methods
Participating investigators from China, Taiwan, India, Japan, South Korea, Sweden, Canada, and the United States were asked beforehand to provide data on the epidemiology and treatment outcome of women in their countries.
Results
Comparisons of the epidemiologic and clinical outcome data of women with breast cancer showed significant similarities, but the striking difference is that the peak age is between 40 and 50 years in Asian countries, but is between 60 and 70 years in Western countries. The incidence of breast cancer in Asia is rising and is associated with increased mortality. In the West, although the incidence is also increasing, the mortality rate is definitely decreasing.
Discussion
Future prospective data collection from Asian and Western countries may provide further interesting epidemiologic and outcome data regarding the outcome of women with breast cancer from Asian and Western countries.
We demonstrate that, in contrast to most two-dimensional materials, ultrathin flakes of InSe are stable under ambient conditions. Despite their ambient stability, InSe-based nanodevices show an ...environmental p-type doping, suppressed by capping InSe with hexagonal boron nitride. By means of transport experiments, density functional theory and vibrational spectroscopy, we attribute the p-type doping assumed by uncapped InSe under an ambient atmosphere to the decomposition of water at Se vacancies. We have estimated the site-dependent adsorption energy of O2, N2, H2O, CO and CO2 on InSe. A stable adsorption is found only for the case of H2O, with a charge transfer of only 0.01 electrons per water molecule.
A numerical and experimental study of plasma jet propagation in a low-temperature, atmospheric-pressure, helium jet in ambient air is presented. A self-consistent, multi-species, two-dimensional ...axially symmetric plasma model with detailed finite-rate chemistry of helium-air mixture composition is used to provide insights into the propagation of the plasma jet. The obtained simulation results suggest that the sheath forms near the dielectric tube inner surface and shields the plasma channel from the tube surface. The strong electric field at the edge of the dielectric field enhances the ionization in the air mixing layer; therefore, the streamer head becomes ring-shaped when the streamer runs out of the tube. The avalanche-to-streamer transition is the main mechanism of streamer advancement. Penning ionization dominates the ionization reactions and increases the electrical conductivity of the plasma channel. The simulation results are supported by experimental observations under similar discharge conditions.
Highlights ► The VDR was present in dopamine neurons in adult human and rat substantia nigra. ► The VDR was restricted to the nuclear compartments. ► The rat VDR was expressed between E12 and E15 and ...its abundance increased till P21.
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