Long-term Evolution of Solar Activity and Prediction of the Following Solar Cycles

Solar activities have a great impact on modern high-tech systems,such as human aerospace activities,satellite communication and navigation,deep space exploration,and related scientific research.Therefore,studying the long-term evolution trend of solar activity and accurately predicting the future solar cycles are highly anticipated.Based on the wavelet transform and empirical function fitting of the longest recorded data of the annual average relative sunspot number(ASN)series of 323 yr to date,this work decisively verifies the existence of the solar century cycles and confirms that its length is about 104.0 yr,and the magnitude has a slightly increasing trend on the timescale of several hundred years.Based on this long-term evolutionary trend,we predict solar cycles 25 and26 by using phase similar prediction methods.As for solar cycle 25,its maximum ASN will be about146.7±33.40,obviously stronger than solar cycle 24.The peak year will occur approximately in 2024,and the period will be about 11±1 yr.As for solar cycle 26,it will start around 2030,and reach its maximum between2035 and 2036,with maximum ASN of about 133.0±3.200,and period of about 10 yr.

Comparison of cell salvage with one and two suction devices during cesarean section in patients with placenta previa and/or accrete: a randomized controlled trial

Background:Cell salvage has recently been recommended for obstetric use in cases with a high risk of massive hemorrhage during cesarean section(CS).However,limited data are available to support the use of one suction device to collect lost blood.This study aimed to investigate the volume of red blood cells(RBCs)salvaged and the components of amniotic fluid(AF)in blood salvaged by one suction device or two devices during CS in patients with placenta previa and/or accrete.Methods:Thirty patients with placenta previa and/or accrete undergoing elective CS in the Women's Hospital of Zhejiang University School of Medicine were recruited for the present study from November 1,2017 to December 1,2018.The patients were randomly assigned to one of the two groups according to an Excel-generated random number sheet:Group 1(w=15),in which only one suction device was used to aspirate all blood and AF,and Group 2(w=15),in which a second suction device was mainly used to aspirate AF before the delivery of the placenta.Three samples of blood per patient(pre-wash,post-wash,and post-filtration)were collected to measure AF components.The salvaged RBC volumes were recorded.Continuous data of pre-wash,post-wash,and postfiltration samples were analyzed by using one-way analysis of variance with Tukey5s test for multiple comparisons,or Kruskal-Wallis test with Dunn test for multiple comparisons.Comparisons of continuous data between Group 1 and Group 2 were conducted using Student's t test or Mann-Whitney U test.Results:The salvaged RBC volume was significantly higher in Group 1 than that in Group 2(401.6±77.2 mL vs.330.1土53.3 mL,?=4.175,P<0.001).In both groups,squamous cells,lamellar bodies,and fat were significantly reduced by washing(all P<0.001)and squamous cells were further reduced by filtering(P<0.001).Squamous cells were found in six post-filtration samples(three from each group).Lamellar bodies and fat were completely removed by filtering.Insulin-like growth factor binding protein 1,alphafetoprotein,albumin,lactate dehydrogenase,and potassium were significantly reduced post-wash(all P<0.05),with no further significant reduction after filtration in either group(all P>0.05).The mean percentage of fetal RBCs post-filtration was(1.8±0.8)%with a range of 1.0%to 3.5%and(1.9±0.9)%with a range of 0.7%to 4.0%in Groups 1 and 2,respectively,showing no significant difference between the two groups(U=188.5,P=0.651).Conclusion:Cell salvage performed by one suction device could result in higher volume of salvaged RBCs and can be used safely for CS in patients with placenta previa and/or accrete when massive hemorrhage occurs.Trial registration number:ChiCTR-INR-17012926,http://www.chictr.org.cn/Chinese Clinical Trial Registry.