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Several studies have demonstrated the influence of sea surface temperature (SST) in the Indian Ocean on the interannual variability of the Tanzanian long rains (TLR). A new investigation into the south‐central tropical Indian Ocean (SCTIO) SST–TLR relationship has been undertaken, focusing on the modulating role played by the Interdecadal Pacific Oscillation (IPO). The relationship experienced interdecadal change during the early 1990s and was strong (weak) during the 1950–1990 (1991–2010) period. Further diagnosis revealed that the interdecadal change is closely associated with changes in atmospheric circulation anomalies induced by the SCTIO SST anomalies (SSTAs). Prior to the early 1990s, warm SCTIO SST induced anomalous upper‐level cyclone and easterlies over Tanzania, which led to evidence of abnormal subsidence over this region. These were accompanied by an early onset of the Southeast Asia monsoon (SAM) to promote dryness in Tanzania. Easterlies, cyclones and SAMs ceased to exist after the early 1990s. The SCTIO SSTA alone does not induce distinct atmospheric circulation anomalies linked to the TLR variation. It was found that IPO is a crucial factor modulating the nonstationary SCTIO SST–TLR relationship. Prior to the early 1990s, IPO‐related SSTA induced anomalous descending motion through the atmospheric bridge, resulting in northeasterly (easterly) over the north Indian (eastern Indian) Ocean. These anomalies also affect the mixed‐layer depth (latent heat flux), which in turn alters the SST, warming the whole Indian Ocean basin. In this case, the SCTIO SSTA exerts significant influence on the TLR, independent of the IPO. After the early 1990s, sea surface height anomalies from the Pacific propagate through the oceanic pathway to the SCTIO, which in turn modifies SSTs. During the 1991–2010 period, a weaker SCTIO SST–TLR association correlated with a stronger SCTIO SST–IPO relationship. We suggest that the IPO may act as a crucial modulator for the SCTIO SST–TLR relationship. [ABSTRACT FROM AUTHOR]

Background: Thalassemia is one of the most common monogenetic diseases in the south of China and Southeast Asia. Hemoglobin Bart's hydrops fetalis syndrome was caused by a homozygous Southeast Asian deletion (-/-) in the HBA gene. Few studies have proved the potential of screen for Bart's hydrops fetalis using fetal cell-free DNA. However, the number of cases is still relatively small. Clinical trials of large samples would be needed.Objective: In this study, we aimed to develop a noninvasive method of target-captured sequencing and genotyping by the Bayesian method using cell-free fetal DNA to identify the fetal genotype in pregnant women who are at risk of having hemoglobin Bart hydrops fetalis in a large-scale study.Study Design: In total, 192,173 couples from 30 hospitals were enrolled in our study and 878 couples were recruited, among whom both the pregnant women and their husbands were detected to be carriers of Southeast Asian type (-/αα) of α-thalassemia. Prenatal diagnosis was performed by chorionic villus sampling, amniocentesis, or cordocentesis using gap-polymerase chain reaction considered as the golden standard.Results: As a result, we found that the sensitivity and specificity of our noninvasive method were 98.81% and 94.72%, respectively, in the training set as well as 100% and 99.31%, respectively, in the testing set. Moreover, our method could identify all of 885 maternal samples with the Southeast Asian carrier and 36 trisomy samples with 100% of sensitivity in T13, T18, and T21 and 99.89% (1 of 917) and 99.88% (1 of 888) of specificity in T18 and T21, respectively.Conclusion: Our method opens the possibility of early screening for maternal genotyping of α-thalassemia, fetal aneuploidies in chromosomes 13/18/21, and hemoglobin Bart hydrops fetalis detection in 1 tube of maternal plasma. [ABSTRACT FROM AUTHOR]