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Energy storage safety is an important component of national energy security and economic development; it has significant impacts on national security, sustainable development, and social stability. The sodium battery technology is considered as one of the most promising grid-scale energy storage technologies owing to its high power density, high energy density, low cost, and high safety. In this article, we highlight the technical advantages and application scenarios of typical sodium battery systems, including sodiumsulfur batteries and sodium-metal chloride batteries. Moreover, we propose the possible development directions of sodium battery technology in China. Furthermore, we suggest supporting the fundamental research and engineering development for sodium batteries, promoting the aggregation of related upstream and downstream industries, and establishing related standards and a performance evaluation platform. These aim to improve the R&D level and technology maturity of China’s sodium battery technologies and provide alternative and reliable choices for the safe energy supply in China.

Leaf area index (LAI) is an important index to describe the growth status and canopy structure of vegetation, is of great theoretical and practical significance to quickly obtain LAI of large area vegetation and crops for ecosystem science research and agricultural & forestry production guidance. In this study, the typical tropical crop rubber tree in Hainan Island was selected as the research area, the LAI estimation model of rubber plantation based on satellite remote sensing vegetation indices was constructed, and its spatiotemporal variation was analyzed. The results showed that, compared with correlations between LAI and the indices of normalized difference vegetation index (NDVI), green NDVI (GNDVI), ratio vegetation index (RVI) and wide dynamic range vegetation index (WDRVI), correlations were higher between LAI and the indices of enhanced vegetation index (EVI), soil adjusted vegetation index (SAVI), difference vegetation index (DVI) and modified soil adjusted vegetation index (MSAVI). Among the LAI estimation models based on different vegetation indices (linear, exponential and logarithmic models), the linear estimation model based on EVI index was the best, and its coefficient of determination (R2) was 0.69. The accuracy of LAI estimation model was high. The linear fitting R2 of observed and simulated LAI was 0.67, the root mean square error (RMSE) was 0.16, and the average relative error (RE) was -0.25%. However, there was underestimation in the middle value and overestimation in the high and low value area of LAI. The high LAI values (4.40－6.23) were mainly distributed in Danzhou and Baisha in the west of Hainan Island, the middle LAI values (3.80－4.40) were mainly distributed in Chengmai, Tunchang and Qiongzhong in the middle of Hainan Island, and the low LAI values (2.69－3.80) were mainly distributed in Ding'an, Qionghai, Wanning, Ledong and Sanya in the east and south of Hainan Island. In summary, the linear estimation model for rubber plantation LAI based on EVI index obtained high accuracy, and has good values of popularization and appliance.

Aiming at the problem of delayed repair of cracks in the airtight wall of the goaf, a method to initiate crack repair using microcapsules in the initial stage of crack evolution of the airtight wall (cracking period) is proposed. This method makes use of the stress at the crack tip. The microcapsule wall is torn to allow the repair agent wrapped in the wall of the capsule to flow out and fill the gap. After the curing reaction, crack repair is completed. During the crack repair process of the airtight wall, the particle size of the microcapsule affects the strength of the capsule wall and directly affects the repair effect. In order to study the influence of particle size on the strength of microcapsules, eight kinds of microcapsules with different particle diameters and the same wall thickness were prepared by orthogonal experiments. The particle size and wall thickness were characterized by SEM, and the strength of the capsule wall was measured using nanoindentation technology. The quadratic function relationship that the strength of the capsule wall decreases with the increase of the particle size is obtained.

Influence of the type and dosage of latex powder on the tensile bond strength between polymer modified cement mortar and steel plate was researched under three curing conditions. The results show that, the standard and heat aging curing condition to improve the tensile bond strength between polymer modified cement mortar and steel substrate are more conducive than the soaking curing condition. The glass transition temperature (Tg) and minimum film forming temperature (MFFT) of latex powder have little effect on the bond strength between polymer modified cement mortar and steel plate substrate. The properties of latex powder also affect the tensile bond strength, the flow promoting EVA latex powder can improve the bond strength of cement mortar under soaking curing condition to a certain extent. Acrylate latex powder has no obvious effect on improving the tensile bond strength between cement mortar and steel plate. The bond failure between polymer modified cement mortar and steel plate substrate is basically the internal failure of mortar, which has nothing to do with the curing conditions. Through secondary electronic imaging technology, it is found that under the standard curing system, when the content of latex powder is 25%, the polymer film covers the surface of cement hydration products. The number of pores in the structure of acrylate latex powder film increased significantly. [ABSTRACT FROM AUTHOR]

The core waterborne polyurethane (WPU) is modified by methyl methacrylate (MMA). Taking the solid content and water absorption as evaluation indexes, the optimal modification conditions are determined by orthogonal test. The optimal modification conditions are as follows: the mass ratio of MMA to WPU is 1.5:1.0, the reaction time is 4h, and the reaction temperature is 70 t. Microcapsules are prepared by interfacial polymerization. The results show that when the content of waterborne polyurethane is 10% and emulsifier is 1.2%, the encapsulation rate and permeability of microcapsules are the best. [ABSTRACT FROM AUTHOR]

Objective: To investigate the clinical outcome of patients with moderate type of coronavirus disease 2019 (COVID-19) after discharge by retesting viral nucleic acid., Methods: Seven patients with moderate COVID-19 met the discharge criteria enacted by National Health Commission were quarantined in hospital for 7 days, then continuously quarantined at home for 4 weeks after discharged. During the quarantined period, the symptoms and signs were documented, and sputum or nasal swab and feces samples were collected to test SARS-CoV-2 nucleic acid by RT-PCR method., Results: There was no symptoms and signs during the quarantine period in all 7 patients. However, respiratory swabs from 3 patients were confirmed positive of SARS-CoV-2 nucleic acid at 5 to 7 days after they met the discharge criteria., Conclusions: There is a relatively high incidence of positive viral nucleic acid in patients met the discharge criteria, and it is suggested that patients met the current discharge criteria should be quarantined in hospital for another 7 days and the follow-up viral testing is necessary.

Objective: To investigate the status of cardiopulmonary resuscitation (CPR) in patients with sudden cardiac arrest (CA) in the emergency department., Methods: A multicenter prospective observational study was conducted. The patients with CA admitted to 13 hospitals from 6 provinces in four different regions, including North China, Southern China, East China, Southwest China, from July 1st, 2015 to July 31st, 2017 were enrolled. A modified Utstein template was applied to collect clinical data, including general data, CA related data and prognosis, and primary outcome indicator was the return of spontaneous circulation (ROSC) rate, and the secondary outcome indicator was 28-day survival rate. The influence factors of ROSC were screened by Logistic regression analysis., Results: The data of 613 patients with CA in 13 hospitals were enrolled. The ROSC rate in Beijing and Guangdong Province was higher, but there was no significant difference in 28-day survival rate among hospitals from different provinces. (1) In 613 patients with CA, there were 413 patients suffering from in-hospital cardiac arrest (IHCA, 67.4%), and 200 suffering from out-hospital cardiac arrest (OHCA, 32.6%). 208 patients had ROSC at least once (33.9%), only 20 patients survived within 28 days (3.3%). ROSC rate in IHCA patients was significantly higher than that in OHCA patients [37.3% (154/413) vs. 27.0% (54/200), P < 0.01]. There was no statistic difference in 28-day survival rate between patients with IHCA and OHCA. The patients received manual chest compression, electric defibrillation, or epinephrine ≤ 4 mg had higher ROSC rate, but 28-day survival rate showed no significant difference. Multivariate Logistic regression analysis showed that IHCA [odds ratio (OR) = 1.893, 95% confidence interval (95%CI) = 1.253-2.858, P = 0.002], manual chest compression (OR = 0.506, 95%CI = 0.348-0.736, P = 0.000), electric defibrillation (OR = 0.458, 95%CI = 0.300-0.699, P = 0.000), and total adrenalin ≤ 4 mg (OR = 0.317, 95%CI = 0.216-0.464, P = 0.000) were the protective factors of ROSC in CA patients. (2) In 200 OHCA patients, there were 49 patients had ROSC (24.5%), only 5 patients survived (2.5%). The patients aging < 65 years, with witnesses of CPR, received manual chest compression, electric defibrillation, or epinephrine ≤ 4 mg had higher ROSC rate, and the ROSC rate was higher in ambulances than that at home and in public sites, but 28-day survival rate showed no significant difference. Multivariable Logistic regression analysis showed that age < 65 years old (OR = 2.749, 95%CI = 1.192-6.336, P = 0.018), manual chest compressions (OR = 0.196, 95%CI = 0.072-0.535, P = 0.001), electric defibrillation (OR = 0.263, 95%CI = 0.108-0.641, P = 0.003), total adrenaline dose ≤ 4 mg (OR = 0.122, 95%CI = 0.049-0.303, P = 0.000) and the ambulance CA (OR = 2.441, 95%CI = 1.334-4.468, P = 0.004) were protective factors of ROSC in OHCA patients., Conclusions: The survival of sudden CA in emergency department was still poor. Early electric defibrillation, manual chest compression, CA occurred in hospital or in ambulance, and witness CPR can improve the ROSC rate of CA patients. Excessive use of adrenaline is not beneficial to patients with CA., Clinical Trials: NCT01987245.

It's necessary to interrupt cardiopulmonary resuscitation (CPR) for a reliable automatic external defibrillator (AED) rhythm analysis, because the mechanical activity from the chest compressions introduces artifacts in the electrocardiogram (ECG) that substantially lower the capacity of an AED to judge cardio-electric rhythm. However, repeated interruptions of compression will reduce the quality of CPR, which in turn affect the prognosis of patients with cardiac arrest (CA). In order to improve the quality of CPR, reduce the interruptions of chest compression and implement accurate defibrillation, people have made many efforts on identifying ECG rhythm in CPR. The studies can be grouped into two broad categories: those based on the artificial mixture of ECG data and CPR artifacts and those based on CA data recorded during CPR. This article introduced researches for rhythm recognition in CPR, including sources and characteristics of CPR artifacts, methods of rhythm analysis, and provided a basis for the study of how to improve the accuracy of cardio-electric rhythm recognition.

Objective: To observe the effect of different airway pressure on ventilation, organ perfusion and return of spontaneous circulation (ROSC) of cardiac arrest (CA) pigs during cardiopulmonary resuscitation (CPR), and to explore the possible beneficial mechanism of positive airway pressure during CPR., Methods: Twenty healthy landrace pigs of clean grade were divided into low airway pressure group (LP group, n = 10) and high airway pressure group (HP group, n = 10) with random number table. The model of ventricular fibrillation (VF) was reproduced by electrical stimulation, and mechanical chest compressions and mechanical ventilation (volume-controlled mode, tidal volume 7 mL/kg, frequency 10 times/min) were performed after 8 minutes of untreated VF. Positive end expiratory pressure (PEEP) in LP group and HP group was set to 0 cmH 2 O and 6 cmH 2 O (1 cmH 2 O = 0.098 kPa) respectively. Up to three times of 100 J biphasic defibrillation was delivered after 10 minutes of CPR. The ROSC of animals were observed, and the respiratory parameters, arterial and venous blood gas and hemodynamic parameters were recorded at baseline, 5 minutes and 10 minutes of CPR., Results: The number of animals with ROSC in the HP group was significantly more than that in the LP group (8 vs. 3, P < 0.05). Intrathoracic pressure during chest compression relaxation was negative in the HP group, and its absolute value was significantly lower than that in LP group at the same time [intrathoracic negative pressure peak (cmH 2 O): -4.7±2.2 vs. -10.8±3.5 at 5 minutes, -3.9±2.8 vs. -6.5±3.4 at 10 minutes], however, there was significantly difference only at 5 minutes of CPR (P < 0.01). Intrathoracic pressure variation during CPR period in the HP group were significantly higher than those in the LP group (cmH 2 O: 22.5±7.9 vs. 14.2±4.4 at 5 minutes, 23.1±6.4 vs. 12.9±5.1 at 10 minutes, both P < 0.01). Compared to the LP group, arterial partial pressure of oxygen [PaO 2 (mmHg, 1 mmHg = 0.133 kPa): 81.5±10.7 vs. 68.0±12.1], venous oxygen saturation (SvO 2 : 0.493±0.109 vs. 0.394±0.061) at 5 minutes of CPR, and PaO 2 (mmHg: 77.5±13.4 vs. 63.3±10.5), arterial pH (7.28±0.09 vs 7.23±0.11), SvO 2 (0.458±0.096 vs. 0.352±0.078), aortic blood pressure [AoP (mmHg): 39.7±9.5 vs. 34.0±6.9], coronary perfusion pressure [CPP (mmHg): 25.2±9.6 vs. 19.0±7.6], and carotid artery flow (mL/min: 44±16 vs. 37±14) at 10 minutes of CPR in the HP group were significantly higher (all P < 0.05). Arterial partial pressure of carbon dioxide (PaCO 2 ) in the HP group was significantly lower than that in the LP group at 10 minutes of CPR (mmHg: 60.1±9.7 vs. 67.8±8.6, P < 0.05)., Conclusions: Compared to low airway pressure, a certain degree of positive airway pressure can still maintain the negative intrathoracic pressure during relaxation of chest compressions of CPR, while increase the degree of intrathoracic pressure variation. Positive airway pressure can improve oxygenation and hemodynamics during CPR, and is helpful to ROSC.

Objective: To study the clinical characteristics, antibiotics sensitivity, outcome and risk factors of neonatal septicemia caused by Candida haemulonii., Method: A retrospective analysis was performed on clinical characteristics and antibiotics sensitivity after 8 cases of neonatal septicemia caused by Candida haemulonii were identified; each of these patients had at least one positive result of bacterial culture for Candida haemulonii., Result: The 8 cases born at gestational age of 178-260 d, weighing 835-2 055 g, developed the infection from May to July at 10-34 d after hospitalization. Among the 8 patients, 7 were cured, 1 died during hospitalization after the treatments were given up because of serious complications. The 8 patients with septicemia caused by Candida haemulonii had similar clinical chariacteristics to those of other neonatal candidemia, such as apnea, fever, abdominal distension, jaundice etc. They had abnormal auxiliary examination with increased C-reactive protein (CRP), declined platelet (PLT) count to different degrees. All of the 8 patients had peripherally inserted central catheter (PICC) and broad-spectrum antibiotics were applied. C. haemulonii as an emergent fungal pathogen had varying degrees of resistance to fluconazole, amphotericin B, itraconazole, or ketone, but was susceptible to voriconazole., Conclusion: The characteristics of neonatal septicemia caused by Candida haemulonii were similar to those caused by other candida, and the main risk factors are the low birth weight, PICC, and usage of broad-spectrum antibiotics. It mainly occurred in May to July which is hot and humid season.

Objective: To explore the effects of seven kinds of hemoglobin variants on two HbA1c detection methods., Methods: Twenty-five hemoglobin variant samples (Hb D, S, Q, G, J, E & F) and 40 control samples were from February 2012 to April 2013 collected. All samples were tested by ion exchange-high performance liquid chromatography system (IE-HPLC) and affinity chromatograghy high performance liquid chromatography (AC-HPLC) respectively.We compared the coincidence between HbA1c results of two instruments and blood glucose and observed the difference between variant and control groups for two methods using statistic software SPSS 19.0., Results: A high consistency existed between IE-HPLC and AC-HPLC in the control group with no hemoglobin variants (6.68% ± 1.87% vs 6.64% ± 1.99%, P > 0.05) . For the hemoglobin variants group, the results of HbA1c via IE-HPLC were interfered by hemoglobin variants (3.57% ± 3.51% than 4.95% ± 0.57%, P < 0.05). However, HbA1c detection of AC-HPLC had no interference with hemoglobin variants and it demonstrated an excellent correlation with blood glucose., Conclusions: The results of HbA1c in blood samples containing common hemoglobin variants may be interfered on IE-HPLC to be falsely lower or higher.Only detecting glycated hemoglobin with strong specificity,AC-HPLC is well-correlated with blood glucose and its results are not interfered by common variant hemoglobin.

In this paper is recommended a highly sensitive and reagent-safe method to determine plasma heamoglobin (FHb) in viscacha hemolytic test. The 2,4-dichlorophenol method (2,4-DCP) of Trinder reaction has been improved. The performance of 2,4-DCP is verified. The sensitivity of 2,4-DCP is 2.39 times that of phenol method. It is well used with run precision and day-to-day precision. The reaction color is stable. The reference value FHb is 1-36.7 mg/L. Sodium citric is an excellent anticoagulant liquid to keep erythrocyte. The 2,4-DCP method is neither carcinogenic nor poisonous;it is suitable for viscacha hemolytic test in clinical and biomedical engineering.