Can labor migration alleviate the constraints of farmers' mobility? An empirical analysis from the perspective of social network

Chinese rural families are facing serious mobility constraints. The impact of COVID-19 pandemic further aggravates farmers' mobility dilemma, which seriously restricts the expansion of rural household consumption. It is of great theoretical value and practical significance to take reasonable and effective measures to alleviate farmers' mobility constraints. Based on the data of China Family Panel Studies (CFPS) from 2014 to 2018, this article empirically examines the impact of labor migration on farmers' mobility constraints. The study finds that, labor migration significantly alleviates farmers' mobility constraints, and this basic conclusion remains robust after the definition of mobility constraints is changed, relaxing the exclusive constraints of instrumental variables and using the propensity score matching method. Further analysis shows that labor migration has a greater easing effect on the mobility constraints of farmers with low social networks, and it reduces the polarization caused by social network inequality such as clan network, endowment of parents, external identity, social and economic status gap. Heterogeneity analysis shows that labor migration has a more significant easing effect on the mobility constraints of middle-aged families, low human capital families and families in north region. This study proposes a new idea to solve the problem of farmers' mobility constraints and provides a new perspective to reduce the internal economic inequality within rural areas and a reference for the formulation of relevant policy-making.

Clinical analysis and early differential diagnosis of suspected pediatric patients with 2019 novel coronavirus infection (preprint)

Background:We aimed to identify clinical features of coronavirus disease 2019 (COVID-19) in children and evaluate the role of procalcitonin in early differential diagnosis. Methods: A retrospective analysis was performed on all suspected pediatric cases. Results: 39 (50.6%) of 77 suspected cases were comfirmed, 4 (5.2%) of them had viral coinfection.Compared with non-COVID-19 group (n=33),COVID-19 confirmed group (n=39) had fewer fever(OR[95% CI]0.467[0.314 to 0.694];P=.000) and symptoms of acute respiratory infection (0.533[0.36 to 0.788];P=.001),more asymptomatic (13.568[1.895 to 96.729];P=.000),and more family cluster infections (5.077[2.224 to 11.591];P=.000),while computed tomography had more positive findings of viral pneumonia (1.822[1.143 to 2.906];P=.008).Age(6.9[3.6 to 10.5] vs 5[2.1 to 7.6];P=.088) and gender were statistically insignificant.Procalcitonin (0.05[0.029 to 0.076] vs 0.103[0.053 to 0.21];P=.000) of COVID-19 alone group (n=35) was significantly reduced.While compared with coinfection group (n=4),procalcitonin (0.05[0.029 to 0.076] vs 0.144[0.109 to 2.26];P=.010) was also reduced.The area under curve of model is 0.834 ([95%CI][0.741 to 0.926];P=.000).Procalcitonin as a differential indicator of COVID-19 alone,its area under curve is 0.809 ([0.710 to 0.909];P=.000). The optimal cut-off value is 0.1 ng/mL,the sensitivity, specificity, positive and negative predictive value of differentiating are 65.9%, 78.6%, 82.9%, and 59.2%,respectively. Conclusions: Asymptoms or mild symptoms,positive computed tomography findings and family cluster infection are the main clinical features of COVID-19 in children.With good performance, procalcitonin can provide an important basis for differentiating COVID-19 alone and other viral infection or viral coinfection. Keywords:children;coronavirus disease 2019;differential diagnosis; procalcitonin; suspected

Clinical characteristics of a group of deaths with COVID-19 pneumonia in Wuhan, China: retrospective case series (preprint)

Background: With the widespread outbreak of novel coronavirus diseases 2019(COVID-19), more and more death cases were reported, however, limited data are available for the patients who died. We aimed to explore the clinial characteristics of deaths with COVID-19 pneumonia Methods: We abstracted and analyzed epidemiological, demographic, clinical, and laboratory data from 83 death cases with COVID-19 pneumonia in East hospital of Wuhan university Renmin hospital,between January 26, 2020, and February 28, 2020.Results: Of the 83 deaths, none was the medical staff. The mean age was 71.8 years (SD 13.2; range, 34-97 years) and 53(63.9%) were male. The median from onset to admission was 10 days (IQR 7-14: range, 2-43 days), to death was 17days (IQR 14-21: range, 6-54 days). Most deaths (66[80%]) had underlying comorbid diseases, the most of which was hypertension [47(57%)]. The main initial symptoms of these 83 deaths were shortness of breath(98.8%), fever(94%) and myalgia or fatigue(90.4%). Laboratory analyses showed the lymphocytopenia in 69(83%) deaths, hypoalbuminemia in 77(93%) deaths, the elevation of lactate dehydrogenase in 79(95%) deaths, procalcitonin in 69(83%) deaths and C-reactive protein in 79(95%) deaths. All 83 patients received antiviral treatment, 81(97.6%) deaths received antibiotic therapy, and 54(65.1%) deaths received glucocorticoid therapy and 20(24.1%) patients received invasive mechanical ventilation.Conclusion: Most of the deaths with COVID-19 pneumonia were elderly patients with underlying comorbid diseases, especially those over 70 years of age. The time of death was mostly 15-21 days after the onset of the disease. More care should be given to the elderly in the further prevention and control strategies of COVID-19.

Clinical characteristics of 82 death cases with COVID-19 (preprint)

Background A recently developing pneumonia caused by SARS-CoV-2 was originated in Wuhan, China, and has quickly spread across the world. We reported the clinical characteristics of 82 death cases with COVID-19 in a single center. Methods Clinical data on 82 death cases laboratory-confirmed as SARS-CoV-2 infection were obtained from a Wuhan local hospital's electronic medical records according to previously designed standardized data collection forms. Findings All patients were local residents of Wuhan, and the great proportion of them were diagnosed as severe illness when admitted. Most of the death cases were male (65.9%). More than half of dead patients were older than 60 years (80.5%) and the median age was 72.5 years. The bulk of death cases had comorbidity (76.8%), including hypertension (56.1%), heart disease (20.7%), diabetes (18.3%), cerebrovascular disease (12.2%), and cancer (7.3%). Respiratory failure remained the leading cause of death (69.5%), following by sepsis syndrome/MOF (28.0%), cardiac failure (14.6%), hemorrhage (6.1%), and renal failure (3.7%). Furthermore, respiratory, cardiac, hemorrhage, hepatic, and renal damage were found in 100%, 89%, 80.5%, 78.0%, and 31.7% of patients, respectively. On the admission, lymphopenia (89.2%), neutrophilia (74.3%), and thrombocytopenia (24.3%) were usually observed. Most patients had a high neutrophil-to-lymphocyte ratio of >5 (94.5%), high systemic immune-inflammation index of >500 (89.2%), increased C-reactive protein level (100%), lactate dehydrogenase (93.2%), and D-dimer (97.1%). A high level of IL-6 (>10 pg/ml) was observed in all detected patients. Median time from initial symptom to death was 15 days (IQR 11-20), and a significant association between aspartate aminotransferase (p=0.002), alanine aminotransferase (p=0.037) and time from initial symptom to death were interestingly observed. Conclusion Older males with comorbidities are more likely to develop severe disease, even die from SARS-CoV-2 infection. Respiratory failure is the main cause of COVID-19, but either virus itself or cytokine release storm mediated damage to other organ including cardiac, renal, hepatic, and hemorrhage should be taken seriously as well.