Paleoclimate evolution of the North Pacific Ocean during the late Quaternary: Progress and challenges

High- and low-latitude climatic processes in the North Pacific Ocean are important components of the global climate system. For example, the interplay among North Pacific atmospheric circulation, ocean circulation, and biological productivity affects atmospheric carbon dioxide levels and marine oxygen concentrations. Here we review recent research on the North Pacific paleoclimatic and paleoceanographic evolution during the late Quaternary and its response to external forcings such as orbital insolation, ice-sheet extent, and greenhouse gas concentrations. First, we summarize the principles and application of relative paleointensity as a critical chronological tool in North Pacific paleoclimate research. Second, we illustrate the latest discoveries on the interaction between North Pacific Intermediate Water formation and high-to-low latitude teleconnection processes. Third, recent progress in linking dust fluxes and marine productivity and their global significance for the carbon cycle are presented. Finally, several key scientific problems are highlighted for future research on ocean-atmosphere-climate interactions in the North Pacific, pointing to the importance of combining paleo-records and modeling simulations. Overall, this review also aims to provide a broad insight into possible future changes of ocean-atmosphere circulation in the North Pacific region under a rapidly warming climate

Optical sensing interface based on nano-opto-electro-mechanical systems

A novel optical sensing interface based on nano-opto-electro-mechanical systems (NOEMS) is proposed, in which the light can be coupled with quantum tunneled electrons via weak mechanical coupling. By taking optical pump power and mechanical coupling strength as varying parameters, respectively, bifurcation diagrams of three involved dynamical states of the NOEMS, i.e., optical, electrical and mechanical mode, are calculated, from which an effective coupling region for tunneled electrons and light is revealed. Self-oscillation, transient dynamics and the threshold of the NOEMS are further characterized, and it is found that the effective coupling region has a special transient time. The work sheds light in developing ultra-sensitive photon detectors using physical mechanisms rather than the conventional PN junction based

Asynchronous variation in the Quaternary East Asian winter monsoon associated with the tropical Pacific ENSO‐like system

Quaternary East Asian winter monsoon (EAWM) evolution has long been attributed to high-latitude Northern Hemisphere climate change. However, it cannot explain the distinct relationships of the EAWM in the northern and southern East Asian marginal sea in paleoclimatic records. Here we present an EAWM record of the northern East China Sea over the past 300 ka and a transient climate simulation with the Kiel Climate Model through the Holocene. Both proxy record and simulation suggest anticorrelated long-term EAWM evolution between the northern East China Sea and the South China Sea. We suggest that this spatial discrepancy of EAWM can be interpreted as El Niño–Southern Oscillation (ENSO)-like controlling, which generates cyclonic/anticyclonic wind anomalies in the northern/southern East Asian marginal sea. This research explains much of the controversy in nonorbital scale variability of Quaternary EAWM records in the East Asian marginal sea and supports a potent role of tropical forcing in East Asian winter climate change

Interactions between depositional regime and climate proxies in the northern South China Sea since the Last Glacial Maximum

Sedimentary deposits from the northern South China Sea (SCS) can provide important constraints on past changes in ocean currents and the East Asian summer monsoon (EASM) in this region. However, the interpretation of such records spanning the last deglaciation is complicated because sea-level change may also have influenced the depositional processes and patterns. Here, we present new records of grain size, clay mineralogy, and magnetic mineralogy spanning the past 24 kyr from both shallow and deep-water sediment cores in the northern SCS. Our multi-proxy comparison among multiple cores helps constrain the influence of sea-level change, providing confidence in interpreting the regional climate-forced signals. After accounting for the influence of sea-level change, we find that these multi-proxy records reflect a combination of changes in (a) the strength of the North Pacific Intermediate Water inflow, (b) the EASM strength, and (c) the Kuroshio Current extent. Overall, this study provides new insights into the roles of varying terrestrial weathering and oceanographic processes in controlling the depositional record on the northern SCS margin in response to climate and sea-level fluctuations

Distinct control mechanism of fine-grained sediments from Yellow River and Kyushu supply in the northern Okinawa Trough since the last glacial

© 2017. American Geophysical Union. All Rights Reserved. High-resolution multiproxy records, including clay minerals and Sr-Nd-Pb isotopes of the clay-sized silicate fraction of sediments from IODP Site U1429 in the northern Okinawa Trough, provide reliable evidence for distinct control mechanism on fine-grained sediments input from the Yellow River and the southern Japanese Islands to the northern Okinawa Trough since 34 ka BP. Provenance analysis indicates that the sediments were mainly derived from the Yellow River and the island of Kyushu. Since the last glacial, clay-sized sediments transported from the Yellow River to the study site were strongly influenced by sea-level fluctuation. During low sea-level stage (∼34–14 ka BP), the paleo-Yellow River mouth was positioned closer to the northern Okinawa Trough, favoring large fluvial discharge or even direct input of detrital sediments, which resulted about four times more flux of clay-sized sediments supply to the study area as during the relatively high sea-level stage (∼14–0 ka BP). The input of Kyushu-derived clay-sized sediments to the study site was mainly controlled by the Kuroshio Current and Tsushima Warm Current intensity, with increased input in phase with weakened Kuroshio Current/Tsushima Warm Current. Our study suggests that the Kuroshio Current was very likely flowed into the Okinawa Trough and thus influenced the fine-grained sediment transport in the area throughout the last glacial and deglacial. During ∼34–11 ka BP, the Kyushu clay-sized sediment input was mainly controlled by the Kuroshio Current. Since ∼11 ka BP, the occurrence of Tsushima Warm Current became important in influencing the Kyushu fine-grained sediment input to the northern Okinawa Trough

Schizophrenia plausible protective effect of microRNA-137 is potentially related to estrogen and prolactin in female patients

BackgroundSchizophrenia (SCZ) is a serious chronic mental disorder. Our previous case–control genetic association study has shown that microRNA-137 (miR-137) may only protect females against SCZ. Since estrogen, an important female sex hormone, exerts neuroprotective effects, the relationship between estrogen and miR-137 in the pathophysiology of SCZ was further studied in this study.MethodsGenotyping of single-nucleotide polymorphism rs1625579 of miR-137 gene in 1,004 SCZ patients and 896 healthy controls was conducted using the iMLDR assay. The effect of estradiol (E2) on the miR-137 expression was evaluated on the human mammary adenocarcinoma cell line (MCF-7) and the mouse hippocampal neuron cell line (HT22). The relationships between serum E2, prolactin (PRL), and peripheral blood miR-137 were investigated in 41 SCZ patients and 43 healthy controls. The miR-137 and other reference miRNAs were detected by real-time fluorescent quantitative reverse transcription-PCR.ResultsBased on the well-known SNP rs1625579, the distributions of protective genotypes and alleles of the miR-137 gene were not different between patients and healthy controls but were marginally significantly lower in female patients. E2 upregulated the expression of miR-137 to 2.83 and 1.81 times in MCF-7 and HT22 cells, respectively. Both serum E2 and blood miR-137 were significantly decreased or downregulated in SCZ patients, but they lacked expected positive correlations with each other in both patients and controls. When stratified by sex, blood miR-137 was negatively correlated with serum E2 in female patients. On the other hand, serum PRL was significantly increased in SCZ patients, and the female patients had the highest serum PRL level and a negative correlation between serum PRL and blood miR-137.ConclusionThe plausible SCZ-protective effect of miR-137 may be female specific, of which the underlying mechanism may be that E2 upregulates the expression of miR-137. This protective mechanism may also be abrogated by elevated PRL in female patients. These preliminary findings suggest a new genetic/environmental interaction mechanism for E2/miR-137 to protect normal females against SCZ and a novel E2/PRL/miR-137-related pathophysiology of female SCZ, implying some new antipsychotic ways for female patients in future

Fludarabine, cytarabine, granulocyte colony-stimulating factor, and idarubicin with gemtuzumab ozogamicin improves event-free survival in younger patients with newly diagnosed aml and overall survival in patients with npm1 and flt3 mutations

Purpose To determine the optimal induction chemotherapy regimen for younger adults with newly diagnosed AML without known adverse risk cytogenetics. Patients and Methods One thousand thirty-three patients were randomly assigned to intensified (fludarabine, cytarabine, granulocyte colony-stimulating factor, and idarubicin [FLAG-Ida]) or standard (daunorubicin and Ara-C [DA]) induction chemotherapy, with one or two doses of gemtuzumab ozogamicin (GO). The primary end point was overall survival (OS). Results There was no difference in remission rate after two courses between FLAG-Ida + GO and DA + GO (complete remission [CR] + CR with incomplete hematologic recovery 93% v 91%) or in day 60 mortality (4.3% v 4.6%). There was no difference in OS (66% v 63%; P = .41); however, the risk of relapse was lower with FLAG-Ida + GO (24% v 41%; P < .001) and 3-year event-free survival was higher (57% v 45%; P < .001). In patients with an NPM1 mutation (30%), 3-year OS was significantly higher with FLAG-Ida + GO (82% v 64%; P = .005). NPM1 measurable residual disease (MRD) clearance was also greater, with 88% versus 77% becoming MRD-negative in peripheral blood after cycle 2 (P = .02). Three-year OS was also higher in patients with a FLT3 mutation (64% v 54%; P = .047). Fewer transplants were performed in patients receiving FLAG-Ida + GO (238 v 278; P = .02). There was no difference in outcome according to the number of GO doses, although NPM1 MRD clearance was higher with two doses in the DA arm. Patients with core binding factor AML treated with DA and one dose of GO had a 3-year OS of 96% with no survival benefit from FLAG-Ida + GO. Conclusion Overall, FLAG-Ida + GO significantly reduced relapse without improving OS. However, exploratory analyses show that patients with NPM1 and FLT3 mutations had substantial improvements in OS. By contrast, in patients with core binding factor AML, outcomes were excellent with DA + GO with no FLAG-Ida benefit

Economic Analysis of Atomization Drying of Concentrated Solution Based on Zero Discharge of Desulphurization Wastewater

With the improvement of environmental protection requirements, more and more attention has been given to desulphurization wastewater with zero discharge in coal power plants. Atomization drying is part of the main zero discharge technologies at present. Economic analysis of the atomization drying of desulphurization wastewater is beneficial to the formulation of an appropriate operation scheme and to the reduction of operation costs. The economic analysis and sensitivity analysis of different operating conditions such as unit load, the handling capacity of concentrates, and the temperature of the extracted flue gas in the atomization drying process of concentrated desulfurized wastewater were carried out in this paper. The main cost of the drying process came from the influence of flue gas extraction on the overall heat transfer in the boiler, resulting in the decrease in power generation revenue, which can reach more than 80%. The operating cost of auxiliary machinery was relatively low. The cost of treatment for per ton of concentrates increased first and then decreased with the increase in temperature of the extracted flue gas, and it decreased with the increase in the handling capacity of the concentrates. The effect of a unit load on the treatment cost was also related to the temperature of the extracted flue gas, and the optimal flue gas temperature increase to higher temperatures as the unit load decreased. The minimum treatment costs per ton of concentrate ranged from CNY 143.54/t to CNY 158.77/t under different unit loads. Sensitivity analysis showed that the temperature of the extracted flue gas had the greatest impact on treatment cost, and its sensitivity coefficient was 0.0834. The ways in which to improve economic benefits were discussed

Economic Analysis of Atomization Drying of Concentrated Solution Based on Zero Discharge of Desulphurization Wastewater

With the improvement of environmental protection requirements, more and more attention has been given to desulphurization wastewater with zero discharge in coal power plants. Atomization drying is part of the main zero discharge technologies at present. Economic analysis of the atomization drying of desulphurization wastewater is beneficial to the formulation of an appropriate operation scheme and to the reduction of operation costs. The economic analysis and sensitivity analysis of different operating conditions such as unit load, the handling capacity of concentrates, and the temperature of the extracted flue gas in the atomization drying process of concentrated desulfurized wastewater were carried out in this paper. The main cost of the drying process came from the influence of flue gas extraction on the overall heat transfer in the boiler, resulting in the decrease in power generation revenue, which can reach more than 80%. The operating cost of auxiliary machinery was relatively low. The cost of treatment for per ton of concentrates increased first and then decreased with the increase in temperature of the extracted flue gas, and it decreased with the increase in the handling capacity of the concentrates. The effect of a unit load on the treatment cost was also related to the temperature of the extracted flue gas, and the optimal flue gas temperature increase to higher temperatures as the unit load decreased. The minimum treatment costs per ton of concentrate ranged from CNY 143.54/t to CNY 158.77/t under different unit loads. Sensitivity analysis showed that the temperature of the extracted flue gas had the greatest impact on treatment cost, and its sensitivity coefficient was 0.0834. The ways in which to improve economic benefits were discussed