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Abstract Background Azygos vein aneurysm (AVA) is a rare thoracic pathological entity that mimics a posterior mediastinal mass. However, the pathogenesis of primary azygos vein aneurysms is not clear and its pathology is still being discussed. Some of the AVA are asymptomatic and usually discovered accidentally by routine physical examination. Case presentation We report the case of a 37-year-old woman who had an azygos vein arch aneurysm with no obvious clinical symptoms. With the analysis of clinical features of the case and AVA morphological characteristics, the AVA was found by a chest computed tomography. Then, enhanced chest computed tomography showed a soft-tissue mass (4.9 × 3.7 × 3.2 cm) in the right posterior mediastinum, which was connected to the superior vena cava and significantly enhanced with contrast agent stratification. The density of the tumor in the delayed stage was the same as that in the azygos vein. The patient underwent video-assisted thoracoscopic surgery. Histopathological evaluation of the surgical biopsy specimen proved to be a completely thrombosed aneurism of the azygos vein arch. Conclusions AVA is a rare pathology that must be taken into consideration during the differential diagnosis of right posterior mediastinal masses. Thoracoscopic surgery is one of the most preferred treatment options for azygos vein aneurysm.

Abstract Background Ewing’s sarcoma is a common malignant bone tumor in children and young adults. Rarely, extra-skeletal soft tissues and visceral organs can also be the site of origin of Ewing’s sarcoma. Primary pulmonary Ewing’s sarcoma is an extremely rare malignancy. Case presentation We report an unusual case of primary pulmonary Ewing’s sarcoma in a 15-year-old girl who initially presented with massive hemothorax. By histopathology evaluation of surgical biopsy specimens, the diagnosis of extraosseous Ewing’s sarcoma was confirmed by both light microscopy and immunohistochemistry. Emergency, open surgery was performed by thoracic surgery at an early stage. After 3 cycles of chemotherapy, the patient was found to be stable at follow-up examination. No more hydrothorax or other symptoms. Conclusions We have described an extremely rare case of primary pulmonary Ewing’s sarcoma with massive hemothorax. The patient underwent surgical resection and postoperative chemotherapy, no sign of recurrence to date as an outcome.

In order to alleviate the cyclic attenuation caused by the dissolution of poly-selenides in lithium/sodium storage devices, quantitative selenium was slowly evaporated on the surface of sodium citrate derived carbon (SCDC) at low temperature, and simultaneously the element Se was doped. Benefiting from the synergistic effects of the domain-limiting effect of embedded nanopores on Se nanoparticles and the stability of SCDC with Se doped during the embedding and stripping of Na ions, Se@C versus sodium metal exhibits high second specific capacity of 485 mAh·g−1 and unexpected stability at 0.1 A g−1 and 1 A g−1. Se@C versus lithium metal exhibits high second specific capacity of 1185 mAh·g−1 at 0.1 A g−1 and excellent stability. Together with the simple and application of synthesis method, Se@C composite is expected to become an anode material for large sodium/lithium storage devices.

The Hadamengou deposit is the largest gold deposit in Inner Mongolia. However, given that the sources of ore-forming alkaline magmatic hydrothermal solutions and ore-controlling structures are still controversial, the theories behind the genesis of the deposit have been controversial. In this study, four controlled-source audio magnetotellurics (CSAMT) and spectral induced polarization (SIP) profiles in the mining area were used to obtain the underground resistivity model and the pseudo section map of the apparent frequency dispersivity based on fine inversion. In the resistivity model, there are two high-resistivity blocks with resistivity greater than 3000 Ω m and three low-resistivity channels with resistivity less than 50 Ω m. Combined with the regional geological and drilling data, it is inferred that the high-resistance bodies, R4 and R5, may be alkaline magmatic intrusions related to multiple stages of magmatic hydrothermal activities, ranging from the Precambrian to Yanshanian periods. The highly conductive channels, C3, C5, and C4, may represent the Baotou-Hohhot fault, secondary faults, and ductile shear zone, respectively, which were formed in the Precambrian era and underwent multiple activations during the Hercynian to Yanshanian period. According to the spatial relationship, it is inferred that the ductile shear zone is an important ore-controlling and ore-hosting structure. However, the Baotou–Hohhot fault may be a pre-metallogenic fault rather than an ore-controlling fault. By comparing the resistivity model with the pseudo section of the apparent frequency dispersivity, it was found that all the known gold veins are located in the superimposed area of low resistivity and high-frequency dispersivity. It is speculated that the ductile shear zone outside the alkaline magmatic rock with the superimposed characteristics of low resistivity and high-frequency dispersivity is the favorable area for mineralization.

The effects of cold deformation on tensile properties and corrosion behavior of the Ti-6Al-3Nb-2Zr-1Mo alloy are investigated in the present work. The microstructure of the sample was characterized by means of x-ray diffractometry, scanning electron microscope and electron backscattered diffraction. The corrosion behavior of the alloy in HCl solution was characterized by potentiodynamic polarization test. The results show that the α laths became kinked after cold rolling and the interlamellar spacing decreased to about 0.45 μ m at the rolling reduction of 50%. The kinking process closely linked with the development of shear bands within the colonies. EBSD investigations indicated that the α lath exhibited a (0001) texture in the 50% cold-rolled alloy. With the increase of cold deformation strain, the Yield strength of the alloy increases from 811 MPa to 943 MPa. The corrosion resistance of processed samples was higher than as-received sample. Experimental results showed that deformation substructure and texture had an influence on the corrosion rate of this alloy.

Abstract Particulate lead (Pb) is a primary air pollutant that affects society because of its health impacts. This study investigates the source sectors of Pb associated with ambient fine particulate matter (PM2.5) over central-western Taiwan (CWT) with new constraints on the Pb-isotopic composition. We demonstrate that the contribution of coal-fired facilities is overwhelming, which is estimated to reach 35 ± 16% in the summertime and is enhanced to 57 ± 24% during the winter monsoon seasons. Moreover, fossil-fuel vehicles remain a major source of atmospheric Pb, which accounts for 12 ± 5%, despite the current absence of a leaded gasoline supply. Significant seasonal and geographical variations in the Pb-isotopic composition are revealed, which suggest that the impact of East Asian (EA) pollution outflows is important in north CWT and drastically declines toward the south. We estimate the average contribution of EA outflows as accounting for 35 ± 15% (3.6 ± 1.5 ng/m3) of the atmospheric Pb loading in CWT during the winter monsoon seasons.

The mixed traffic flow of various types of vehicles at bus station is severe, which has an impact on the overall safety of traffic. Especially upstream of bus station, since buses need to change lane in order to stop at the bus station, it interacts with social vehicles. Thus, in this paper, a two-lane CA model considering the mixed traffic flow composing of buses, cars and nonmotorized vehicles upstream of a bus station is proposed. Through several field surveys, the movement characteristics of the vehicles are obtained and the basic parameters are calibrated. For comparison, five cases about bus stops are studied. Several indexes (i.e. parallel time, blind area dwell time, time to collision, potential collision energy) are analyzed to assess the safety upstream of the bus station. Four safety indices are used to examine, based on simulation findings, the impact of bus station on vehicle safety and the significance of establishing exclusive nonmotorized vehicle lanes and exclusive bus lanes. Finally, several safety-related recommendations for drivers and management are provided. These findings offer a theoretical basis for driver management and optimal design of bus stations. [ABSTRACT FROM AUTHOR]

An exacerbated precipitation–temperature relationship can lead to compound extremes. The role of clouds in such a relationship is relatively uncertain. Here, we investigate the cloud–precipitation–temperature relationships over the Indochina Peninsula during the summer monsoon transition. The negative correlation between cloudiness/precipitation and surface maximum temperature is valid on seasonal and interannual timescales. The near-surface temperature exhibits interdecadal variability and a long-term warming trend. The warming trend has accelerated in the past two decades. In the anomalous warm years, the remarkably strong western Pacific subtropical high inhibits the development of clouds, especially the middle and high cloud-top regimes, leading to the suppression of deep convection and precipitation. There are more optically thin (moderate to thick) clouds with smaller (larger) effective radii in the high cloud-top regime for the warm (cold) years. The dominance of shallow cumulus is a distinct feature in the warm years. The daytime heating of enhanced surface insolation due to decreased cloudiness is worsened by the dry condition of the precipitation deficit. The water vapor warming effect can prevent an efficient drop in nighttime temperature, thereby exacerbating the warm condition under the warming trend. The cloud–precipitation–temperature relationships coupling with the monsoon development can be used to diagnose the regional scale cloud–climate interactions in climate models.

OBJECTIVE: To measure the association between ambient heat and hypoglycemia-related emergency department visit or hospitalization in insulin users. RESEARCH DESIGN AND METHODS: We identified cases of serious hypoglycemia among adults using insulin aged ≥65 in the U.S. (via Medicare Part A/B/D-eligible beneficiaries) and Taiwan (via National Health Insurance Database) from June to September, 2016–2019. We then estimated odds of hypoglycemia by heat index (HI) percentile categories using conditional logistic regression with a time-stratified case-crossover design. RESULTS: Among ∼2 million insulin users in the U.S. (32,461 hypoglycemia case subjects), odds ratios of hypoglycemia for HI >99th, 95–98th, 85–94th, and 75–84th percentiles compared with the 25–74th percentile were 1.38 (95% CI, 1.28–1.48), 1.14 (1.08–1.20), 1.12 (1.08–1.17), and 1.09 (1.04–1.13) respectively. Overall patterns of associations were similar for insulin users in the Taiwan sample (∼283,000 insulin users, 10,162 hypoglycemia case subjects). CONCLUSIONS: In two national samples of older insulin users, higher ambient temperature was associated with increased hypoglycemia risk. [ABSTRACT FROM AUTHOR]