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This study investigates the impact of digital economy development on urban export sophistication and its mechanisms. We use the chain mediation effect model to analyze the panel data of 281 cities in China from 2011 to 2017. The results show that the digital economy has a significant and positive impact on urban ES. There are two main influence paths. One promotes urban ES by accumulating human capital; the other stimulates technological innovation and further leads to urban ES. The "technological innovation effect" plays the most considerable mediating role among them. The heterogeneity test result shows that the digital economy impact is greater in western China than in eastern and central regions. We further show that the influence of the regional digital economy on urban ES presents an inverted U-shaped curve. Our paper provides guidance for promoting the construction of and the high-quality development of trade. [ABSTRACT FROM AUTHOR]

Based on the surface and sounding datasets, ERA5 reanalysis data from European Centre for Medium-Range Weather Forecasts (ECMWF) and the satellite images, the characteristics of convection-triggering drylines in the drainage area of Huanghe and Huaihe Rivers of China from April to September during 2010-2019 are analyzed. The result shows that the drylines mainly appear at Dezhou of Shandong, and surroundings in the north of Henan. Most of them are distributed in the quasi northwest-southeast and northeast-southwest direction, with the length of 100-200 km and the width of 50-100 km, and they generally occur at 1400 BT or 1700 BT during the daytime. The drylines mostly occur under the 500 hPa cold vortex located in Northeast China and North China, with convergence lines (or shear lines) on 700 hPa and 850 hPa weather chart, and within the low pressure behind the coastal high on the surface chart. The statistics of the surface elements shows that the temperature on the dry side is 1.9 ℃ higher than that on the wet side, while the dew point temperature on the wet side is 6.8 ℃ higher than that on dry side. The gradient of temperature, dew point temperature and specific humidity on both sides of drylines are -2.7 ℃·(100 km)-1, 10.1 ℃·(100 km)-1 and 5.9 g·kg-1·(100 km)-1, respectively. According to the statistics of sounding environment parameters, precipitable water in the wet side is higher than that on the dry side. The specific humidity on the wet side is higher than that on the dry side at 925 hPa, 850 hPa and 700 hPa. The mean convective available potential energy on the wet side is much larger than that on the dry side. The temperature differences are very small on both sides of the drylines at 850 hPa and 500 hPa, 700 hPa and 500 hPa. The significant difference on both sides of the dry side in convective available potential energy is mainly caused by the difference in water condition of the lower layers in the drainage area of Huanghe and Huaihe Rivers of China. The hydrostatic instability (conditional instability) on both sides of the drylines is similar. Also, the vertical wind shear of 0-6 km is a little bit stronger on wet side than that on the dry side.

BACKGROUND. Since December 2019, an outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, and is now becoming a global threat. We aimed to delineate and compare the immunological features of severe and moderate COVID-19. METHODS. In this retrospective study, the clinical and immunological characteristics of 21 patients (17 male and 4 female) with COVID-19 were analyzed. These patients were classified as severe (11 cases) and moderate (10 cases) according to the guidelines released by the National Health Commission of China. RESULTS. The median age of severe and moderate cases was 61.0 and 52.0 years, respectively. Common clinical manifestations included fever, cough, and fatigue. Compared with moderate cases, severe cases more frequently had dyspnea, lymphopenia, and hypoalbuminemia, with higher levels of alanine aminotransferase, lactate dehydrogenase, C-reactive protein, ferritin, and D-dimer as well as markedly higher levels of IL-2R, IL-6, IL-10, and TNF-[alpha]. Absolute numbers of T lymphocytes, [CD4.sup.+] T cells, and [CD8.sup.+] T cells decreased in nearly all the patients, and were markedly lower in severe cases (294.0, 177.5, and 89.0 * [10.sup.6]/L, respectively) than moderate cases (640.5, 381.5, and 254.0 * [10.sup.6]/L, respectively). The expression of IFN-[gamma] by [CD4.sup.+] T cells tended to be lower in severe cases (14.1%) than in moderate cases (22.8%). CONCLUSION. The SARS-CoV-2 infection may affect primarily T lymphocytes, particularly [CD4.sup.+] and [CD8.sup.+] T cells, resulting in a decrease in numbers as well as IFN-[gamma] production by [CD4.sup.+] T cells. These potential immunological markers may be of importance because of their correlation with disease severity in COVID-19. TRIAL REGISTRATION. This is a retrospective observational study without a trial registration number. FUNDING. This work is funded by grants from Tongji Hospital for the Pilot Scheme Project, and partly supported by the Chinese National Thirteenth Five Years Project in Science and Technology for Infectious Disease (2017ZX10202201)., Introduction Coronaviruses (CoVs) are a large family of respiratory viruses that can cause diseases ranging from the common cold to the Middle East respiratory syndrome (MERS) and the severe acute [...]

Background Follow-up study of coronavirus disease 2019 (COVID-19) survivors has rarely been reported. We aimed to investigate longitudinal changes in the characteristics of COVID-19 survivors after discharge. Methods A total of 594 COVID-19 survivors discharged from Tongji Hospital in Wuhan from February 10 to April 30, 2020 were included and followed up until May 17, 2021. Laboratory and radiological findings, pulmonary function tests, electrocardiogram, symptoms and signs were analyzed. Results 257 (51.2%) patients had at least one symptom at 3 months post-discharge, which decreased to 169 (40.0%) and 138 (28.4%) at 6-month and 12-month visit respectively. During follow-up period, insomnia, chest tightness, and fatigue were the most prevalent symptoms. Most laboratory parameters returned to normal, whereas increased incidence of abnormal liver and renal function and cardiovascular injury was evidenced after discharge. Fibrous stripes (213; 42.4%), pleural thickening and adhesions (188; 37.5%) and enlarged lymph nodes (120; 23.9%) were the most common radiographical findings at 3 months post-discharge. The abnormalities of pulmonary function included obstructive, restrictive, and mixed, which were 5.5%, 4.0%, 0.9% at 6 months post, and 1.9%, 4.7%, 0.2% at 12 months. Electrocardiogram abnormalities occurred in 256 (51.0%) patients at 3 months post-discharge, including arrhythmia, ST-T change and conduction block, which increased to 258 (61.1%) cases at 6-month visit and were maintained at high frequency (242;49.8%) at 12-month visit. Conclusions Physiological, laboratory, radiological, or electrocardiogram abnormalities, particularly those related to renal, cardiovascular, and liver functions are common in patients who recovered from coronavirus disease 2019 (COVID-19) up to 12 months post-discharge. [ABSTRACT FROM AUTHOR]

This article explored the relationship between intrauterine hypoxia in pregnant women with pregnancy-induced hypertension and the changes in brain and placental parameters detected by three-dimensional power Doppler (3D-CPA). One hundred confirmed pregnant women with hypertension during pregnancy were selected as the case group, and 100 pregnant women with normal pregnancy in the same period were selected as the control group. 3D-CPA was used to examine the fetal brain and placental blood perfusion parameters of the two groups, and the two groups of fetal delivery were detected after the level of oxidative stress products in cord blood, the correlation between 3D-CPA parameters and oxidative stress products was analyzed. The blood vessel index (VI), blood flow index (FI), and vascular blood flow index (VFI) measured values in the placenta tissue of the case group were lower than those of the control group (P<0.05). VI, FI, VFI measured value in the fetal brain of the case group was greater than that of the control group (P<0.05). The measured values of VI; FI, and VFI in the placental tissue of the preeclampsia group were lower than those of the hypertensive disorder group during pregnancy (P<0.05). The measured values of FI, VFI and VI in the fetal brain of the preeclampsia group were greater than those of the hypertensive disease group during pregnancy (P<0.05). The cord blood of the case group contained malondialdehyde (MDA), 8-isoprostaglandin (8-iso), Oxidized low-density lipoprotein (ox-LDL) and heat shock protein-70 (HSP-70) were significantly higher than those of the control group (P<0.05). The VI and VFI in the placenta tissue of patients with pregnancy-induced hypertension were significantly negatively correlated with the levels of MDA, ox-LDL, 8-iso, and HSP-70 in the patient's cord blood (P<0.05), and FI was significantly negatively correlated with ox-LDL, 8-ISO and HSP-70 (P<0.05). The VI of the fetal brain in the pregnancy-induced hypertension group was significantly positively correlated with MDA, 8-iso, and HSP-70 in the umbilical cord blood of the patients (P<0.05), and VFI was significantly positively correlated with 8-iso and HSP-70.3D-CPA examination can find that the level of fetal placental blood flow parameters of pregnant women with pregnancy-induced hypertension is reduced, and the craniocerebral blood flow parameters are compensatedly increased, and it is related to intrauterine hypoxia. [ABSTRACT FROM AUTHOR]