Speleothem CaCO3 δ18O is a commonly employed paleomonsoon proxy. However, inferring local rainfall amount from speleothem δ18O can be complicated due to changing source water δ18O, temperature effects, and rainout over the moisture transport path. These complications are addressed using δ18O of planktonic foraminiferal CaCO3, offshore from the Yangtze River Valley (YRV). The advantage is that the effects of global seawater δ18O and local temperature changes can be quantitatively removed, yielding a record of local seawater δ18O, a proxy that responds primarily to dilution by local precipitation and runoff. Whereas YRV speleothem δ18O is dominated by precession-band (23 ky) cyclicity, local seawater δ18O is dominated by eccentricity (100 ky) and obliquity (41 ky) cycles, with almost no precession-scale variance. These results, consistent with records outside the YRV, suggest that East Asian monsoon rainfall is more sensitive to greenhouse gas and high-latitude ice sheet forcing than to direct insolation forcing.

Although the prevalences of asthma and obesity are increasing substantially in recent decades, very little is known about the possible association between them. We evaluated the roles of leptin, adiponectin, and resistin, which are adipokines produced by adipose tissue, on childhood asthma, and their association with pulmonary function and bronchial hyperresponsiveness. We studied 149 atopic asthmatic children, 37 non-atopic asthmatic children, and 54 healthy children. Body mass index was calculated using height and weight, which were measured on the same day that pulmonary function tests and methacholine challenge tests were performed. Skin prick tests were performed, and total eosinophil count, total serum immunoglobulin E (IgE), serum eosinophil cationic protein, leptin, adiponectin, and resistin were measured in all subjects. Atopic asthmatics had lower resistin levels compared with non-atopic asthma and control groups, but leptin and adiponectin did not show any difference among these three groups. Resistin demonstrated positive correlation with methacholine PC(20) and negative correlations with eosinophil count and serum total IgE. Leptin and adiponectin showed associations with forced expiratory volume in 1 s or forced expiratory flow between 25-75%. Multiple regression analysis revealed that resistin was a significant predictive factor for asthma. There was no direct association between asthma and leptin or adiponectin. Our findings suggest that resistin may play a negative predictive role in asthma. Adiponectin and leptin showed close associations with pulmonary function and may have disease-modifying effects in children with asthma.

[1] Suspended particulate matter from seawater and core top sediments were collected during 2003 Meteor cruise M57/1 in January-February from the continental margin off western South Africa for analysis of alkenones, glycerol dibiphytanyl glycerol tetraether (GDGT) lipids, and planktonic foraminifera. Alkenone analysis of suspended particulates in seawater and core top sediments indicates that U 37 K 0 temperatures were representative of annual mean sea surface temperature. In contrast, GDGT analysis suggests that TEX 86 temperatures are cold-biased due to upward transports of GDGTs produced below the mixed layer. The analysis of plankton tow samples revealed that the d 18 O of Globorotalia inflata in core top sediments could be biased toward lower temperatures due to subsurface calcification. Accordingly, our study shows that each paleotemperature proxy may record different temperature signals in the Benguela upwelling system emphasizing the general need to constrain potential biases in each proxy for better interpreting paleoclimate records.

Amelogenesis imperfecta (AI) can be either isolated or part of a larger syndrome. Junctional epidermolysis bullosa (JEB) is a collection of autosomal-recessive disorders featuring AI associated with skin fragility and other symptoms. JEB is a recessive syndrome usually caused by mutations in both alleles of COL17A1, LAMA3, LAMB3, or LAMC2. In rare cases, heterozygous carriers in JEB kindreds display enamel malformations in the absence of skin fragility (isolated AI). We recruited two kindreds with autosomaldominant amelogenesis imperfecta (ADAI) characterized by generalized severe enamel hypoplasia with deep linear grooves and pits. Whole-exome sequencing of both probands identified novel heterozygous mutations in the last exon of LAMB3 that likely truncated the protein. The mutations perfectly segregated with the enamel defects in both families. In Family 1, an 8-bp deletion (c.3446_3453del GACTGGAG) shifted the reading frame (p.Gly 1149Glufs*8). In Family 2, a single nucleotide substitution (c.C3431A) generated an inframe translation termination codon (p.Ser1144*). We conclude that enamel formation is particularly sensitive to defects in hemidesmosome/basement-membrane complexes and that syndromic and non-syndromic forms of AI can be etiologically related.

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It is important to determine the true nature of glacial-interglacial variations in subtropical North Pacific SSTs. Knowledge of climate sensitivity in the subtropics is essential for understanding the processes that drive climate variability and for predicting future climate change [e.g., Manabe and Broccoli, 1985a]. The attainment of such knowledge requires that the general utility and limitations of the approaches used to reconstruct past SSTs be better understood. As a step toward these goals, we are studying marine sediment samples from the Hawaiian Islands that posses SST records which are better preserved than those found in the deep Pacific, and we are also using multiple approaches to reconstructing past SSTs.We examine the oxygen isotopic composition and assemblages of planktonic foraminifera from the same core and, rather importantly, use a new independent geochemical proxy, the alkenone Oceanographic Setting and Sediment CoresWe present data derived from analyses of marine sediments in two piston cores (PC17 and PC20) collected off Kahe Point on the southwestern shore of Oahu, Hawaii (Figure 1 and Table 1

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We reviewed three sea surface temperature (SST) proxies in the Okinawa Trough (OT): alkenones, planktonic foraminiferal Mg/Ca, and planktonic foraminiferal assemblages. The seasonal and vertical distribution patterns of each proxy-related organism in the water column were reviewed to confirm the applicability of each proxy. In addition, current SSTs (Japan Oceanographic Data Center dataset from 1906 to 2003) were compared with core-top sediment temperatures reconstructed using the proxies. Temperatures calculated using the alkenone unsaturation index represent annual mean SSTs, and temperatures calculated using Mg/Ca of Globigerinoides ruber capture summer to autumn (June-November) SSTs. Core-top August SSTs calculated from planktonic foraminiferal assemblages corresponded well with the observed SSTs, but core-top February temperatures were~3.6°C warmer than the observed SSTs. SST proxy estimates from marine sediments dating back to the late Holocene (0-3 cal ky BP) and the last glacial maximum (18-21 cal ky BP) were compared. Comparisons between proxy SST estimates show that foraminiferal assemblage-based August SSTs were the warmest. Alkenone-based temperature estimates were lower than Mg/Ca-based temperature estimates, probably because the alkenone-based temperature represents the annual mean temperature, whereas the Mg/Ca-based temperature represents the summer-autumn mean temperature. February assemblage SSTs seem to be greatly affected by the statistical technique and/or database used. These results suggest that seasonality should be considered in past SST reconstruction using alkenone and Mg/Ca in the OT. The planktonic foraminiferal assemblage technique does not appear to be promising with respect to accurately reconstructing past SSTs (especially winter) in the OT. Habitat depth may not be an issue because both alkenone producers and G. ruber live at the upper surface mixed layer in the area. Glacial-interglacial changes in the surface hydrography of the OT reconstructed based on the SST and salinity proxies were also reviewed here. The surface hydrography of the OT has been influenced by changes in the Kuroshio Current and the East Asian monsoon system during the late Quaternary. Comparisons of the hydrography records from the OT with records of stalagmites in China, the Tropical Pacific, and the North Atlantic show that there is a teleconnection between them.