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Funding: The study was supported by the Royal Society Commonwealth Science Conference Fellow-on Grant (CSC\R1\170048) and the National Research Foundation Singapore (Marine Science Research and Development Programme project P03). Barium incorporated in coral skeletons has been widely used as paleo proxies to study terrestrial inputs, upwelling and anthropogenic activities in marine environments. However, these applications often face the challenges of poor replication in the coral skeletal Ba/Ca records from multiple coral colonies and complex Ba sources in coastal environments. Recent studies of Ba isotopes in seawater and deep-sea corals have demonstrated the potential to trace Ba sources and water mixing in the ocean, but there is still a lack of calibrations for Ba isotopes in shallow-water corals. In this study, we present the first multi-colony Ba isotope calibration from three shallow-water Porites lutea corals with the contemporaneous in-situ seawater data from the Singapore Strait. We also report the Ba isotope data in the regional water masses around the study area (e.g. South China Sea, Malacca Strait and Johor River estuary). Singapore water Ba concentrations and isotope compositions show a strong influence of terrestrial inputs, following seasonal salinity and monsoon-driven water-mass mixing between the Malacca Strait and the South China Sea. The coral skeletal δ138/134Ba results are generally consistent between the three coral colonies and time-series data closely follow the seasonal δ138/134Ba variations in seawater. Despite the partition coefficient of Ba having a large uncertainty (DBa = 0.91 ± 0.29), the Ba isotope fractionation between the coral skeletons and seawater is relatively constant (Δ138/134Bacoral-sw = -0.28 ± 0.06‰) and shows no significant difference between these corals. The mechanism controlling Ba incorporation and isotope fractionation in coral skeletons remains unclear, but the evidence clearly indicates that the coral skeletal Ba is originated from dissolved Ba in seawater. The constant offset of Ba isotopes between coral skeletons and seawater allows for reliable records of seawater δ138/134Ba values. Ba isotopes in coral skeletons could be used to reconstruct surface water salinity variability in the Singapore Strait, reflecting monsoon driven changes in regional water mass mixing. Postprint

The relationship between leading atmospheric teleconnection patterns and Greenland Ice Sheet (GrIS) temperature, precipitation, and surface mass balance (SMB) are investigated for the last 36 summers (1979-2014) based on Modern-Era Retrospective analysis for Research and Applications version 2 reanalyses. The results indicate that the negative phase of both the North Atlantic Oscillation (NAO) and Arctic Oscillation, associated with warm and dry conditions for the GrIS, lead to SMB decreases within 0-1 months. Furthermore, the positive phase of the East Atlantic (EA) pattern often lags the negative NAO, reflecting a dynamical linkage between these modes that acts to further enhance the warm and dry conditions over the GrIS, leading to a favorable environment for enhanced surface mass loss. The development of a strong negative NAO in combination with a strong positive EA in recent years leads to significantly larger GrIS warming compared to when the negative NAO occurs in combination with a negative or weak positive EA (0.69 K versus 0.13 K anomaly). During 2009 and 2011, weakened (as compared to conditions during the severe surface melt cases of 2010 and 2012) local high pressure blocking produced colder northerly flow over the GrIS inhibiting warming despite the occurrence of a strong negative NAO, reflecting an important role for the EA during those years. In particular, the EA acts with the NAO to enhance warming in 2010 and 2012, and weaken high pressure blocking in 2009 and 2011. In general, high pressure blocking primarily impacts the western areas of the GrIS via advective temperature increases, while changes in net surface radiative fluxes account for both western and eastern GrIS temperature changes.

The androgen receptor (AR) has a critical role in promoting androgen-dependent and -independent apoptosis in testicular cells. However, the molecular mechanisms that underlie the ligand-independent apoptosis, including the activity of AR in testicular stem cells, are not completely understood. In the present study, we generated induced pluripotent stem cells (iPSCs) from bovine testicular cells by electroporation of octamer-binding transcription factor 4 (OCT4). The cells were supplemented with leukemia inhibitory factor and bone morphogenetic protein 4, which maintained and stabilized the expression of stemness genes and pluripotency. The iPSCs were used to assess the apoptosis activity following exposure to phthalate esters, including di (2-ethyhexyl) phthalates, di (n-butyl) phthalate, and butyl benzyl phthalate. Phthalate esters significantly reduced the expression of AR in iPSCs and induced a higher ratio of BAX/BCL-2, thereby favoring apoptosis. Phthalate esters also increased the expression of cyclin-dependent kinase inhibitor 1 (p21Cip1) in a p53-dependent manner and enhanced the transcriptional activity of p53. The forced expression of AR and knockdown of p21Cip1 led to the rescue of the phthalate-mediated apoptosis. Overall, this study suggests that testicular iPSCs are a useful system for screening the toxicity of environmental disruptors and examining their effect on the maintenance of stemness and pluripotency, as well as for identifying the iPSC signaling pathway(s) that are deregulated by these chemicals.