Search

Throat aurora was defined based on the ground observations near local noon and has been suggested to be the ground signature of an indentation on the subsolar magnetopause. A global view of the auroral oval with throat aurora will be critical for inferring global processes at the magnetopause, but it has never been achieved. Using imaging spectrograph observations from Defense Meteorological Satellite Program satellites, for the first time, here we show typical throat auroras in a global view and reveal some important observational facts as follows. (1) The throat auroras can be as long as ~8 degrees in latitudinal direction, which is hardly to be fully seen in the ground-based camera. (2) The plasma flows and field aligned currents associated with throat aurora show consistences with previous radar observations, which have been suggested to be the observational evidence of magnetopause reconnection. (3) Most importantly, we confirmed that the electron and ion precipitations associated with throat aurora are always spatially separated, i.e., electrons in the east and ions in the west. The observational results not only establish a new picture of the aurora oval near local noon, but also provide important support to a conceptual model of throat aurora.

In this paper, we report a p-GaN/n-ZnO nanoplate/CsPbBr3 quantum dots (QDs) heterojunction light-emitting diode (LED) for dual-wavelength emission. ZnO nanoplates were prepared by vapor phase transport on the GaN thin film to form the p-GaN/n-ZnO nanoplate heterojunction. Afterwards, green CsPbBr3 QDs (band gap of 2.25 eV) were deposited on ZnO nanoplates to realize green light emission. The structure and photoluminescence of the ZnO nanoplates and CsPbBr3 QDs were characterized. The as-prepared LED device with turn-on voltage of ∼ 2.7 V displays a typical rectification behavior. The electroluminescence spectra with narrow emission peaks reveal the device presents commendable dual-wavelength electroluminescence performance at ∼ 385 nm and ∼ 512 nm and the electroluminescence intensity saturates at about 65 mA/cm2. Moreover, the detailed electroluminescence mechanism including emission originate of n-ZnO/p-GaN heterojunction was discussed based on the band diagram. Thus, our work indicates compelling potential for the practical application of perovskite LEDs.

To explore the clinical and imaging characteristics and summarize the causes of missed diagnosis of reversible posterior leukoencephalopathy syndrome (RPLS) in eclampsia. We collected the data of a total of 45 patients with RPLS who were misdiagnosed initially (27 cases were confirmed and 18 cases were suspicious) out of 804 patients with severe eclampsia who had presented themselves to the Affiliated Hospital of Xuzhou Medical University from January 2014 to December 2016. We summarized the clinical and imaging characteristics of the patients and analyzed the possible causes of the misdiagnosis. Among the 804 patients with eclampsia, 45 were misdiagnosed the first time. Their clinical manifestations included headache (20 cases), epilepsy (13 cases), blurred vision (11 cases), disturbance of consciousness (2 cases), and drowsiness (3 cases). The parietal lobe was involved in 22 cases, the occipital lobe in 15 cases, the frontal lobe in 20 cases, basal ganglia in 9 cases, and the temporal lobe in 8 cases. Low-density lesions were observed on computed tomography (CT) scans. Head magnetic resonance (MR) scans showed hypo-intense lesions on T1-weighted image (T1WI), hyper-intense lesions on the T2-weighted image (T2WI) and fluid-attenuated inversion recovery (FLAIR), iso-intense or slightly hyper-intense lesion on diffusion-weighted imaging (DWI), and slightly hyper-intense or hypo-intense lesion on apparent diffusion coefficient (ADC). The incidence of reversible posterior leukoencephalopathy syndrome is extremely high. The clinical features include headache, mental disturbance, seizures, blurred vision, and other neurological symptoms. The lesion area is mainly limited to the parietal and occipital lobes; however, the frontal lobe, basal ganglia, temporal lobe, corpus callosum, and cerebellum can also be involved. The prognosis is good with timely and appropriate treatments.

An evolutionarily conserved alveolar epithelial progenitor lineage that derives from alveolar type 2 cells is responsive to Wnt signalling and acts as a major facultative progenitor in regenerating the distal lung. The lung, which relies on complex distal gas exchange units called alveoli for its function, is a highly quiescent organ, displaying a very low turnover of cells in its normal state. However, it is prone to environmental and infectious damaging agents. Elucidating how organs that are maintained in a mainly quiescent state regenerate after injury could help in the development of therapeutic strategies to promote organ repair. Edward Morrisey and colleagues have identified and characterized an alveolar epithelial progenitor that is responsive to Wnt and FGF7 signalling triggered by injury and that exists in mouse and human adult lungs. The human alveolar epithelial progenitors can be isolated and grown in three-dimensional organoids, highlighting their potential for future regeneration strategies. Functional tissue regeneration is required for the restoration of normal organ homeostasis after severe injury. Some organs, such as the intestine, harbour active stem cells throughout homeostasis and regeneration1; more quiescent organs, such as the lung, often contain facultative progenitor cells that are recruited after injury to participate in regeneration2,3. Here we show that a Wnt-responsive alveolar epithelial progenitor (AEP) lineage within the alveolar type 2 cell population acts as a major facultative progenitor cell in the distal lung. AEPs are a stable lineage during alveolar homeostasis but expand rapidly to regenerate a large proportion of the alveolar epithelium after acute lung injury. AEPs exhibit a distinct transcriptome, epigenome and functional phenotype and respond specifically to Wnt and Fgf signalling. In contrast to other proposed lung progenitor cells, human AEPs can be directly isolated by expression of the conserved cell surface marker TM4SF1, and act as functional human alveolar epithelial progenitor cells in 3D organoids. Our results identify the AEP lineage as an evolutionarily conserved alveolar progenitor that represents a new target for human lung regeneration strategies.

Cerebral cavernous malformations (CCMs) are common inherited and sporadic vascular malformations that cause strokes and seizures in younger individuals. CCMs arise from endothelial cell loss of KRIT1, CCM2 or PDCD10, non-homologous proteins that form an adaptor complex. How disruption of the CCM complex results in disease remains controversial, with numerous signalling pathways (including Rho, SMAD and Wnt/β-catenin) and processes such as endothelial-mesenchymal transition (EndMT) proposed to have causal roles. CCM2 binds to MEKK3 (refs 7, 8, 9, 10, 11), and we have recently shown that CCM complex regulation of MEKK3 is essential during vertebrate heart development. Here we investigate this mechanism in CCM disease pathogenesis. Using a neonatal mouse model of CCM disease, we show that expression of the MEKK3 target genes Klf2 and Klf4, as well as Rho and ADAMTS protease activity, are increased in the endothelial cells of early CCM lesions. By contrast, we find no evidence of EndMT or increased SMAD or Wnt signalling during early CCM formation. Endothelial-specific loss of Map3k3 (also known as Mekk3), Klf2 or Klf4 markedly prevents lesion formation, reverses the increase in Rho activity, and rescues lethality. Consistent with these findings in mice, we show that endothelial expression of KLF2 and KLF4 is increased in human familial and sporadic CCM lesions, and that a disease-causing human CCM2 mutation abrogates the MEKK3 interaction without affecting CCM complex formation. These studies identify gain of MEKK3 signalling and KLF2/4 function as causal mechanisms for CCM pathogenesis that may be targeted to develop new CCM therapeutics.

The α–amylase activity of cultivated barley is critically important to the brewing industry. Here, we surveyed variation in malt α–amylase activity in 343 cultivated barley accessions from around the world. Population structure analysis based on genotype data at 1536 SNPs clustered these accessions into two groups, one comprising South-East Asian and Ethiopian accessions and one group containing the other accessions. A genome-wide association study identified significant quantitative trait loci (QTLs) for α–amylase activity on all seven chromosomes of barley. Accessions showing high and low α–amylase activity were crossed with the high-quality Japanese malting barley cv. Harun Nijo to develop F2 mapping populations. We identified two QTLs on chromosome 6H in a cross between Haruna Nijo (high activity) × Weal (highest activity). Single QTLs were identified each on 3H, 4H, and 5H from a cross between Haruna Nijo (high activity) × VLB-1 (low activity), indicating that the high α–amylase activity in Haruna Nijo might be derived from loci on these chromosomes. The addition of the high α–amylase activity QTL alleles from chromosome 6H in cv. Weal further increased the α–amylase activity conferred by alleles of Haruna Nijo. These results demonstrate that a target haplotype can be successfully improved using a strategy comprising diversity analysis of ex situ collections followed by introducing effective new alleles.

A high-density map consisting of 550 markers was constructed based on the segregation data of 95 doubled-haploid lines (DHLs) derived from the cross between a Japanese barley cultivar, Mikamo Golden and a North American barley cultivar, Harrington (MH-DHLs). Quality traits of malt extract (EX), total nitrogen (TN), soluble nitrogen (SN), Kolbach index (KI), diastatic power (DP), wort beta-glucan (WG) and viscosity (VS) were determined in three site/year crops. Quantitative trait loci (QTL) analyses were performed with these quality data sets, using the linkage map. Major QTL controlling EX, SN and KI were mapped on terminal region of 5H with Harrington as effective allele. Another QTL controlling EX was mapped on 2H with Mikamo Golden as effective allele. QTL controlling TN, DP, WG and VS were detected variably in terms of flanking markers and chromosomes depending on site/year. Cleaved amplified polymorphic sequences (CAPS) markers for EX based on the QTL detected on 2H and 5H were developed. Analysis of EX and genotypes of 33 malting barley cultivars from around the world as well as MH-DHLs revealed that the two CAPS marker on 2H and 5H affect EX by a significant difference, suggesting that the two CAPS markers were valuable for marker-assisted selection in malting barley breeding.

The SEN clogging is a serious problem for continuous casting operation and steel quality. The kinetics mathematic model of SEN clogging during steel continuous casting is discussed. The fluid flow and inclusions motion are calculated by means of mathematic model. Effects of diameters of inclusions, roughness of nozzle, diameter of nozzle and casting speed on the entrapment probability are calculated and evaluated. The result shows that inclusions are more easily to attach to the nozzle by the following condition: smaller inclusion size, larger roughness of the wall and the smaller bulk velocity in the nozzle.

The Quxu (曲水) complex is a typical intrusive among the Gangdese batholiths. Two sets of samples collected from the Mianjiang (棉将) and Niedang (聂当) villages in Quxu County, including gabbro, mafic micro-enclaves (MME), and granodiorites in each set, were well dated in a previous SHRIMP zircon U-Pb analysis (47–51 Ma). In this article, the same zircons of the 6 samples were applied for LA ICP-MS Hf isotopic analysis. The total of 6 samples yields 176Hf/177Hf ratio ranging from 0.282 921 to 0.283 159, corresponding to ɛ Hf(t) values of 6.3–14.7. Their Hf depleted-mantle modal ages (T DM) are in the range of 137–555 Ma, and the zircon Hf isotope crustal model ages (T DM C) range from 178 to 718 Ma. The mantle-like high and positive ɛ Hf(t) values in these samples suggest a mantle-dominated input of the juvenile source regions from which the batholith originated. The large variations in eHf(t) values, up to 5-ɛ unit among zircons within a single rock and up to 15-ɛ unit among zircons from the 6 samples, further suggest the presence of a magma mixing event during the time of magma generation. We suggest that the crustal end-member involved in the magma mixing is likely from the ancient basement within the Lhasa terrane itself. The zircon Hf isotopic compositions further suggest that magma mixing and magma underplating at about 50 Ma may have played an important role in creating the crust of the southern Tibetan plateau.

Controlling inclusion composition, from the point of view of thermodynamics, only explains the probability and limit of reaction. However, kinetics makes the nucleation and the velocity of growth of inclusions clear, and these kinetic factors are very important to the quality of slab. The basic kinetic theory of unreacted core model was used to build the mathematical model for the growth of inclusions and the concerned software was developed through Visual Basic 6.0. The time that different radius inclusions attain saturation was calculated to determine the controlling step of reaction between steel and inclusions. The time for the growth of inclusion obtained from the model was in good agreement with the data measured by Japanese Okuyama G, which indicated that the model is reasonable.

This paper examines the purchasing power parity (PPP) hypothesis for the post–Bretton Woods era including the period after the introduction of the euro. The study applies a new nonlinear unit root test to the bilateral real exchange rates (RERs) of both European and other industrial countries with the French franc and German mark (and the euro after 1998), as well as the US dollar as numeraire currencies. The results of the study provide stronger support for PPP than any earlier studies of bilateral PPP for industrial countries and suggest that (1) PPP tends to hold well within the European Union (EU) even before the adoption of the euro, (2) the evidence for PPP becomes more significant for both EU and non-EU countries when the sample period is extended to the euro era, and (3) convergence toward PPP between the EU countries, especially between the euro-area countries, tends to be nonlinear, while it is likely to be linear for the non-EU industrial countries.

Whole-rock and mineral separate Ar-Ar dating was carried out for the Linzizong volcanic rocks at Linzhou Basin in Tibet to constrain the time span of volcanism and the corresponding stratigraphic sequence. Sampling was based on detailed geologic mapping and stratigraphic sequence of Dianzhong, Nianbo, Pana Formations, systematically from the bottom to near the top. The results indicate that the Linzizong volcanic rocks erupted from Paleocene to middle of Eocene (64.43· 43.93 Ma). Among them, the Pana Formation formed from ca. 48.73 to 43.9 Ma, the Nianbo Formation around 54 Ma and the Dianzhong Formation from 64.4 to 60.6 Ma. In combination with evidence from the geochemical characteristics of the volcanic rocks, and from stratigraphy in southern Tibet, it is postulated that the age of the lowest member in the Dianzhong Formation of the Linzizong volcanic rock, which overlies unconformably the Late Cretaceous Shexing Formation, likely corresponds to the inception of the collision between Indian and Asian continents in southern Tibet.

Recent literature reported conflicting results about the cointegration relationship between the spot and forward exchange rates. Applying rolling cointegration tests to the mark, yen, and Swiss franc with respect to the U.S. dollar for the post-80 period, we find that the relationship between the two rates broke down in the late 1980s. Although they became cointegrated again during the mid-90s, they no longer co-moved proportionally. It is argued that failure to account for such significant structural changes in the data generating process explains, at least partially, the conflicting findings reported in the literature.

The trachyte and basaltic trachyte and intruded granite-porphyry of Gazacun formation of Wuyu Group in central Tibet are Neogene shoshonitic rocks. They are rich in LREE, with a weak to significant Eu negative anomalies. The enriched Rb, Th, U, K, negative HFS elements Nb, Ta, Ti and P, and Sr, Nd and Pb isotope geochemistry suggest that the volcanic rocks of Wuyu Group originated from the partial melting of lower crust of the Gangdese belt, with the involvement of the Tethyan oceanic crust. It implies that the north-subducted Tethys ocean crust have arrived to the lower crust of Gangdese belt and recycled in the Neogene magmatism.

This paper analyzes the exchange rate systems of 10 Pacific Basin economies and linkages of their currencies with the major currencies. The recent advances in time series analysis, including unit root tests and cointegration tests, are utilized for this purpose. The results suggest that while many Pacific Basin developing economies are inclined to have a peg or crawling peg system and peg their currencies primarily to the U.S. dollar, the influence of the Japanese yen in this region is also strong, especially on the exchange rates of the Asian newly industrializing economies. For Australia and New Zealand, their exchange rates move in tandem.

Characteristics of the hyperhydric protocormlike-bodies (hPLBs) and the normal PLBs (nPLBs) of Doritaenopsis are morphologically and ontogenetically compared. The hPLBs have a translucent and turgid appearance which is due to a lack of air volume in the intercellular spaces. The hPLBs have a lower capacity of shoot formation but a higher capacity of differentiation of new PLBs than the nPLBs. The new PLBs derived from the hPLBs can be recovered from hyperhydricity using a medium containing potato juice. This suggests the possibility that hPLBs can be used for the in vitro propagation of orchid plants.

This paper provides empirical evidence that the weekly bid-ask spread in the Polish free foreign exchange market is heavily affected by the intensity of sociopolitical unrest in this country. A GARCH model is estimated to study the volatility of the free market for dollars in Poland from the third week of October 1988 to the fourth week of January 1990. This period is interesting and important because it includes social and political events under two different government regimes. Empirical evidence suggests that significant sociopolitical turmoil appears to increase the volatility of the market and consequently create substantial changes in the spread. The results of this paper may represent valuable information for other reforming countries.

This paper examines the responsiveness of the balance of trade of the People's Republic of China to the real exchange rate. We find that, in both the short-run and the long-run, devaluation serves to improve the balance of trade. Using quarterly data for 1980:I to 1989:IV we show that the bulk of the response to devaluation occurs over a one year period, with noJ-curve effect. These results suggest that the two-tier price system and other measures to liberalize the Chinese economy have made the exchange rate an effective indirect tool for regulating trade.

This paper examines whether there is a tendency for actual exchange rates to return to their fundamental equilibrium exchange rates (FEERs) when the latter are estimated based on popular exchange rate models. Co-integration tests and unit root tests are applied. There is little evidence that the exchange rates of Japan and Germany have a reversion to the purchasing-power-parity (PPP) rates or Williamson's FEERs or the underlying external and internal balance (UEI) FEERs.