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The rainfall changes in East Asian summer monsoon (EASM) regions on the orbital timescale remain controversial due to the lack of reliable rainfall records. Here, we present new multiproxy records (δ18O, δ13C, Sr/Ca and Mg/Ca) of a 230Th-dated stalagmite from Hulu Cave in central eastern China. Multiproxy records reconstruct a regional hydroclimate history from 340 to 261 kyr BP (thousand years before present), approximately covering the antepenultimate glacial period. The δ18O record is dominated by the precessional cycles, suggesting that EASM responds to changes in Northern Hemisphere summer insolation (NHSI) on the orbital timescale. Significant correlations amongst the δ13C, Sr/Ca and Mg/Ca suggest that a common factor, i.e., the local hydrological cycle, controlled their variability, and their leading principal component can be used as a proxy linked to regional rainfall. This composite record bears a good similarity to those from the Chinese Loess Plateau, showing a gradually decreasing rainfall during the antepenultimate glacial period, consistent with changes in global ice volume. Superimposed on the long-term trend, three relative wetter intervals were responding to the higher NHSI periods, suggesting that EASM rainfall variability was induced by integrated effects of global ice volume and NHSI. The increased ice sheets and lower NHSI resulted in an increased meridional temperature gradient and southward shift of the westerlies, which shortened the duration of Meiyu and midsummer rainfall. The differences between the rainfall record and the stalagmite δ18O record indicate that the latter represents the overall EASM intensity linked to monsoon circulation, but does not directly reflect the rainfall changes at the cave sites. [ABSTRACT FROM AUTHOR]

Wheat is a major staple food crop worldwide because of the unique properties of wheat flour. High molecular weight glutenin subunits (HMW-GSs), which are among the most critical determinants of wheat flour quality, are responsible for the formation of glutenin polymeric structures via interchain disulfide bonds. We herein describe the identification of a new HMW-GS Dy10 allele (Dy10-m619SN). The amino acid substitution (serine-to-asparagine) encoded in this allele resulted in a partial post-translational cleavage that produced two new peptides. These new peptides disrupted the interactions among gluten proteins because of the associated changes to the number of available cysteine residues for interchain disulfide bonds. Consequently, Dy10-m619SN expression decreased the size of glutenin polymers and weakened glutens, which resulted in wheat dough with improved cookie-making quality, without changes to the glutenin-to-gliadin ratio. In this study, we clarified the post-translational processing of HMW-GSs and revealed a new genetic resource useful for wheat breeding. [ABSTRACT FROM AUTHOR]

Based on 467 pairs of δ18O and δ13C records and 8 230Th dates from a stalagmite (BF4) from Xiniu Cave, central China, we present a reconstruction of ∼9-yr resolution monsoon rainfall record for the past 4700 years. Our δ18O record shows good coherence with East Asian summer monsoon (EASM) rainfall proxies from adjacent regions during the overlapping intervals, suggesting that δ18O signal in BF4 can be interpreted as a monsoon rainfall proxy. The δ13C variations are related to changes in local processes at the cave site, and regional rainfall and temperature changes. Based on the δ18O record, a series of dry periods can be identified at 4500–1200, 3500–3200, 2800–2500, 1900–1600, 1400–1200, 700–500, and 400–200 yr BP, while a series of wet periods can be identified at 4200–3600, 2400–2200, 3200–2800, 1100–900, 600–400, and 200–100 yr BP. Power spectrum analysis on our δ18O record reveals significant cycles at ∼470 and ∼80 yr, coinciding with the typical solar periodic variations. This result suggests that changes in solar activity play a dominant role in driving centennial-decadal monsoon rainfall variation in central China. Due to minor changes in solar irradiance (less than 1.5 W m−2) over the past 4700 years, our record was further compared to the El Niño-Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO) proxies, confirming that solar forcing on monsoon rainfall changes might be amplified by the ENSO and PDO variations. From 600 to 150 yr BP (the Little Ice Age, LIA), a positive shift of ∼2‰ can be revealed in both the δ18O and δ13C records, indicating a cold/dry climatic pattern. By comparing our δ18O and δ13C records with historical documents, we suggest that the climatic deteriorations between 450 and 250 yr BP may have caused serious social unrest at the end of the Ming Dynasty. [ABSTRACT FROM AUTHOR]

We present a 230Th-dated stalagmite oxygen isotope (δ18O) record from Loushanguan Cave in the Yangtze River valley, China. The δ18O record, if viewed as a proxy of the Asian summer monsoon (ASM) intensity, provides an ASM history for the early Holocene with clear centennial-scale variability. A significant approximately 200-yr cycle between 10.2 and 9.1 ka BP (before present, where "present" is defined as the year AD 1950), as revealed by spectral power analyses, is of global significance and is probably forced by the Suess or de Vries cycle of solar activity. Here, we explore a physical mechanism to explain the relationship between the solar activity and the ASM. A strong coherence between the ASM and El Niño-Southern Oscillation (ENSO) has been observed by performing cross-wavelet analyses on this cycle. Our study suggests that a strong (weak) ASM state corresponds to a warm (cold) ENSO, which is consistent with modern meteorological observations but contrasts with previous studies on regions far from the Meiyu rainbelt. We argue that the centennial fluctuations of the ASM are a fundamental characteristic forced by the solar activity, with the ENSO variability as a mediator. The relationship between ENSO and the ASM displayed spatial heterogeneity on the centennial scale during the early Holocene, which is a more direct analogue to the observed modern interannual variability of the ASM. [ABSTRACT FROM AUTHOR]

We report the ferromagnetism with Cure temperature T at 230 K in a new diluted magnetic semiconductor (DMS) (BaK)(ZnMn)As isostructural to ferropnictide 122 superconductors synthesized via low temperature sintering. Spin is doped by isovalence substitution of Mnfor Zn, while charge is introduced by heterovalence substitution of K for Ba in (BaK)(ZnMn)As DMS, being different from (Ga,Mn)As where both spin & charge are induced simultaneously by heterovalence substation of Mn for Ga. The (BaK)(ZnMn)As DMS shows spontaneous magnetization following T dependence expected for a homogeneous ferromagnet with saturation moment 1.0 μ for each Mn atom [ABSTRACT FROM AUTHOR]

We report discovery of ferromagnetism in (LaCa)(ZnMn)SbO isostructural to the well-studied iron-based superconductor LaFeAs(OF). Spin is induced by partial substitution of Mn for Zn, while charge is induced by substitution of Ca for La within the parent compound LaZnSbO. Ferromagnetism with Curie temperature ( T) is observed up to 40 K at the spin doping 0.15 by introducing Mn into the Zn sites for (LaCa)(ZnMn)SbO. The Hall coefficient measurement indicates p-type carrier for (LaCa)(ZnMn)SbO with concentration of n∼10 cm showing anomalous Hall effect below T. [ABSTRACT FROM AUTHOR]

miRNAs play an important role in the pathogenesis of cardiac hypertrophy and dysfunction. However, little is known about how miR-30a regulates cardiomyocyte hypertrophy. In the study, Male C57BL/6 mice were subjected to thoracic aortic constriction, and hearts were harvested at 3 weeks. We assayed miR-30a expression level by real-time PCR and defined the molecular mechanisms of miR-30a-mediated cardiomyocyte hypertrophy. We found that myocardial expression of miR-30a was decreased in mouse models of hypertrophy and in H9c2 cells treated with phenylephrine. MiR-30a inhibition markedly increased mRNA expression of cardiac hypertrophy markers such as atrial natriuretic factor and brain natriuretic peptide in H9c2, and cell size was increased after miR-30a inhibitor treatment. Downregulated miR-30a activated autophagy by inhibiting beclin-1 expression in H9c2 cell. More important, autophagy inhibition suppressed miR-30a inhibitor-induced cardiomyocyte hypertrophy. Together, our data demonstrated that downregulated miR-30a aggravates pressure overload-induced cardiomyocyte hypertrophy by activating autophagy, thus offering a new target for the therapy of cardiomyocyte hypertrophy. [ABSTRACT FROM AUTHOR]

LiFeAs single crystal has been grown with superconducting transition temperature T comparable to that of polycrystals. A magnetic transition is found at about 160 K, which suggests the correlation of superconductivity with spin wave density. [ABSTRACT FROM AUTHOR]

Stable isotope data of precipitation (δ18Op and deuterium excess), drip water (δ18Od), and modern calcite precipitates (δ18Oc and δ13Cc) from Yongxing Cave, central China, are presented, with monthly sampling intervals from June 2013 to September 2016. Moderate correlations between the monthly variation of δ18Op values (from − 11.5 to − 0.7‰) and precipitation amount (r = − 0.59, n = 34, p < 0.01) and deuterium excess (r = 0.39, n = 31, p < 0.01) imply a combined effect of changes in precipitation amount and atmospheric circulation. At five drip sites, the δ18Od values have a much smaller variability (from − 9.1 to − 7.5‰), without seasonal signals, probably a consequence of the mixing in the karst reservoir with a deep aquifer. The mean δ18Od value (− 8.4‰) for all drip waters is significantly more negative than the mean δ18Op value (− 6.9‰) weighted by precipitation amount, but close to the wet season (May to September) mean value (− 8.3‰), suggesting that a threshold of precipitation amount must be exceeded to provide recharge. Calculation based on the equilibrium fractionation factor indicates that the δ18Oc values are not in isotopic equilibrium with their corresponding drip waters, with a range of disequilibrium effects from 0.4 to 1.4‰. The δ18Oc and δ13Cc values generally increase progressively away from the locus of precipitation on glass plates. The disequilibrium effects in the cave are likely caused by progressive calcite precipitation and CO2 degassing related to a high gradient of CO2 concentration between drip waters and cave air. Our study provides an important reference to interpret δ18Oc records from the monsoon region of China. [ABSTRACT FROM AUTHOR]