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Reconstructing the Holocene megaflood history is a key component of understanding the mechanism of past climate change and assessing the potential impact of future catastrophic events. The Pearl River is the longest watercourse in southern China, and its lower reach has been identified as one of the world's most vulnerable regions for flood exposure. However, there is a complete lack of millennial-scale geological records of paleomegafloods for the future prediction of once-in-a-hundred (even once-in-a-thousand) year floods in southern China. Here, we identified a series of paleomegaflood deposits interbedded with wood-rich peat layers in the lower West Pearl River area. All paleoflood layers have been well dated using AMS 14C dating method. According to the regional correlation of the flood sequence, sediment characteristics and provenance analysis, there have been at least 7 megafloods corresponding to once-in-a-thousand-year events in the lower reaches of the West Pearl River during the past 6000 years, with an average return period of approximately 855 years. The identified paleomegafloods were coeval with periods of strong El Niño-Southern Oscillation (ENSO), indicating that weakening of the Asian summer monsoon, associated with enhanced ENSO variability, may have triggered abnormally high precipitation leading to flooding of exceptional magnitude in southern China. In addition, the most prominent paleomegafloods identified in the lower Pearl River coincided with intervals of lower precipitation and fewer storms in central-eastern China, indicating the intensification of the meridional "tripole" pattern of precipitation across eastern China during the latter half of the Holocene. Increased land use and deforestation over the last 2000 years have resulted in soil loss and rapid degradation of local primeval forest ecosystems, leading to more catastrophic flooding. Large amounts of rice pollen in the uppermost flood layer during the Song Dynasty indicate that this megaflood may have inundated a large area of cultivated land. The periodic occurrence of Holocene megafloods not only caused damage to human existence, but also affected the evolution of local civilization. This study reveals for the first time a series of Holocene millennial-scale megafloods and sheds new light on the importance of atmosphere-ocean interactions in the tropical Pacific and monsoon subtropical climate dynamics for precipitation anomalies in East Asia. Our data yield valuable information for future research into climate extremes and hazard prevention. [ABSTRACT FROM AUTHOR]

Nowadays, more and more federated learning algorithms have been implemented in edge computing, to provide various customized services for mobile users, which has strongly supported the rapid development of edge intelligence. However, most of them are designed relying on the reliable device-to-device communications, which is not a realistic assumption in the wireless environment. This paper considers a realistic aggregation problem for federated learning in a single-hop wireless network, in which the parameters of machine learning models are aggregated from the learning agents to a parameter server via a wireless channel with physical interference constraint. Assuming that all the learning agents and the parameter server are within a distance Γ from each other, we show that it is possible to construct a spanning tree to connect all the learning agents to the parameter server for federated learning within O (log Γ) time steps. After the spanning tree is constructed, it only takes O (log Γ) time steps to aggregate all the training parameters from the learning agents to the parameter server. Thus, the server can update its machine learning model once according to the aggregated results. Theoretical analyses and numerical simulations are conducted to show the performance of our algorithm. [ABSTRACT FROM AUTHOR]

Person reidentification (ReID) is a challenging computer vision task for identifying or verifying one or more persons when the faces are not available. In ReID, the indistinguishable background usually affects the model's perception of the foreground, which reduces the performance of ReID. Generally, the background of the same camera is similar, whereas that of different cameras is quite different. Based on this finding, we propose a template-aware transformer (TAT) method which can learn intersample indistinguishable features by introducing a learnable template for the transformer structure to cut down the model's attention to regions of the image with low discrimination, including backgrounds and occlusions. In the multiheaded attention module of the encoder, this template directs template-aware attention to indistinguishable features of the image and gradually increases the attention to distinguishable features as the encoder block deepens. We also increase the number of templates using side information considering the characteristics of ReID tasks to adapt the model to backgrounds that vary significantly with different camera IDs. Finally, we demonstrate the validity of our theories using various public data sets and achieve competitive results via a quantitative evaluation. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to examine the correlation between maternal body composition during the second trimester and the occurrence of dyslipidemia in the third trimester. Methods: A cohort of 1508 pregnant women who underwent antenatal testing at Shanghai Sixth People's Hospital, affiliated with Shanghai Jiao Tong University School of Medicine, were included in this study. Maternal body composition was assessed using bioimpedance analysis between 14 and 22 weeks of gestation. Results: Among the 1508 participants, a total of 1420 individuals (94.2%) were diagnosed with dyslipidemia. Notably, there were significant differences in body composition between the normal lipid group and the dyslipidemia group. Logistic regression analysis revealed that various factors including BMI, total body water (TBW), intra-cellular water (ICW), extra-cellular water (ECW), percent body fat (PBF), visceral fat area (VFA), fat-free mass (FFM) and arm circumference (AC) during the second trimester were all found to be associated with dyslipidemia in the third trimester. Conclusion: The present study found that maternal body composition was associated with dyslipidemia. The BMI, TBW, ICW, ECW, PBF, VFA, FFM and AC in second trimester were associated with dyslipidemia in third trimester. [ABSTRACT FROM AUTHOR]

This paper studies batch processing of core maintenance in hypergraph streams. We focus on updating the coreness of each vertex after the hypergraph evolves. Unlike existing works that mainly focus on exact coreness updates for the single hyperedge dynamic or approximate update, we propose the first known batch processing algorithms for exact core maintenance with insertions or deletions of multiple hyperedges. By proposing a hyperedge structure Joint Hyperedge Set, we tackle the challenges of quantifying the range of coreness change and finding potential vertices whose coreness may update. In addition, we accelerate coreness updates even further by finding structures that enable parallel execution. Extensive experiments illustrate the efficiency, scalability, and effectiveness of our batch core maintenance algorithms on real-world hypergraphs. It shows that our algorithms can be faster than the single hyperedge processing approaches by a factor of nearly half the number of hyperedges processed, and our parallel algorithms achieve linear acceleration with the increasing number of threads. [ABSTRACT FROM AUTHOR]

Objective To investigate the relationship between disposition index (DI) and the risk of adverse pregnancy outcomes in women with gestational diabetes mellitus (GDM). Methods A total of 1 912 women were prospectively recruited from January 2015 to December 2017 in Department of Gynecology and Obstetrics of the Shanghai Jiao Tong University of Medicine Affiliated Sixth People's Hospital. According to whether they had GDM, they were divided into GDM group (434 cases) and non-GDM group (1 478 cases). All participants received a 75 g oral glucose tolerance test (OGTT) during the 24-28 gestational weeks and complete basal and delivery information was collected. The insulin sensitivity index (ISI) and the area under the insulin curve/area under the blood glucose curve (AUCINS120/AUCGLU120) were calculated from the results of the 75 g OGTT. The DI was calculated as the product of the ISI and AUCINS120/AUCGLU120 and then log transformed. Adverse pregnancy outcomes were defined as large for gestational age (LGA), primary cesarean section, preeclampsia, and preterm birth. Comparison between groups was performed by t test, Wilcoxon rank sum test and χ² test. Logistic regression analysis was used to explore the relationship between DI and the risk of adverse pregnancy outcomes. Results Women with GDM had a lower ISI even DI than women without GDM. Compared with women with GDM in the lowest quartile (Q1, DI<2.90) of DI, multivariable adjusted (age, body mass index, other pregnancy complications, gestational age at the time of OGTT, fetal sex and parity) odds ratios (OR) of adverse pregnancy outcomes of those in the second (Q2, DI 2.90-3.02), third (Q3, DI 3.03-3.16), and highest (Q4, DI>3.16) quartiles of DI were reduced by 55% (95%CI 0.23-0.87), 34% (95%CI 0.35-1.25), and 59% (95%CI 0.24-0.71) (P for trend=0.01), respectively. When DI was considered as a continuous variable, the multivariable adjusted OR of adverse pregnancy outcomes in women with GDM was reduced by 60% (95%CI 0.21-0.73) for each one unit increase in DI. However, DI was not associated with adverse pregnancy outcomes in women without GDM (OR=0.66, 95%CI 0.36-1.18). Conclusion Elevated DI levels in women with GDM are closely associated with a reduced risk of adverse pregnancy outcomes. [ABSTRACT FROM AUTHOR]