A Chinese cave links climate change, social impacts, and human adaptation over the last 500 years.

The collapse of some pre-historical and historical cultures, including Chinese dynasties were presumably linked to widespread droughts, on the basis of synchronicities of societal crises and proxy-based climate events. Here, we present a comparison of ancient inscriptions in Dayu Cave from Qinling Mountains, central China, which described accurate times and detailed impacts of seven drought events during the period of 1520-1920 CE, with high-resolution speleothem records from the same cave. The comparable results provide unique and robust tests on relationships among speleothem δ(18)O changes, drought events, and societal unrest. With direct historical evidences, our results suggest that droughts and even modest events interrupting otherwise wet intervals can cause serious social crises. Modeling results of speleothem δ(18)O series suggest that future precipitation in central China may be below the average of the past 500 years. As Qinling Mountain is the main recharge area of two large water transfer projects and habitats of many endangered species, it is imperative to explore an adaptive strategy for the decline in precipitation and/or drought events.We gratefully acknowledge the NBRPC (2013CB955902), NSFC (41372192; 41290254; 41230524; 41023006), and the WLF-CAS for funding this research. This study was also partially supported by Taiwan MOST (103-2119-M-002-022) and NTU (101R7625) grants. H.C. and R.L.E. received financial support from the U.S. NSF (EAR-0908792 and EAR-1211299), and S.F.M.B. received support from the Swiss NSF (CRSI22_132646/1).This is the final version. It was first published by NPG at http://www.nature.com/srep/2015/150717/srep12284/full/srep12284.html#author-information

A Chinese cave links climate change, social impacts, and human adaptation over the last 500 years

The collapse of some pre-historical and historical cultures, including Chinese dynasties were presumably linked to widespread droughts, on the basis of synchronicities of societal crises and proxy-based climate events. Here, we present a comparison of ancient inscriptions in Dayu Cave from Qinling Mountains, central China, which described accurate times and detailed impacts of seven drought events during the period of 1520–1920 CE, with high-resolution speleothem records from the same cave. The comparable results provide unique and robust tests on relationships among speleothem δ18O changes, drought events, and societal unrest. With direct historical evidences, our results suggest that droughts and even modest events interrupting otherwise wet intervals can cause serious social crises. Modeling results of speleothem δ18O series suggest that future precipitation in central China may be below the average of the past 500 years. As Qinling Mountain is the main recharge area of two large water transfer projects and habitats of many endangered species, it is imperative to explore an adaptive strategy for the decline in precipitation and/or drought events

THE ANTI-TUMOR EFFECT AND BIOLOGICAL ACTIVITIES OF THE EXTRACT JMM6 FROM THE STEM-BARKS OF THE CHINESE JUGLANS MANDSHURICA MAXIM ON HUMAN HEPATOMA CELL LINE BEL-7402

Juglans mandshurica Maxim is a traditional herbal medicines in China, and its anti-tumor bioactivities are of research interest. Bioassay-guided fractionation method was employed to isolate anti-tumor compounds from the stem barks of the Juglans mandshurica Maxim. The anti-tumor effect and biological activities of the extracted compound JMM6 were studied in BEL-7402 cells by MTT, Cell cycle analysis, Hoechst 33342 staining, Annexin V-FITC/PI assay and Detection of mitochondrial membrane potential (△Ψm). After treatment with the JMM6, the growth of BEL-7402 cells was inhibited and cells displayed typical morphological apoptotic characteristics. Further investigations revealed that treatment with JMM6 mainly caused G2/M cell cycle arrest and induced apoptosis in BEL-7402 cells. To evaluate the alteration of mitochondria in JMM6 induced apoptosis. The data showed that JMM6 decreased significantly the △Ψm, causing the depolarization of the mitochondrial membrane. Our results show that the JMM6 will have a potential advantage of anti-tumor, less harmful to normal cells. This paper not only summarized the JMM6 pick-up technology from Juglans mandshurica Maxim and biological characteristic, but also may provide further evidence to exploit the potential medicine compounds from the stem-barks of the Chinese Juglans mandshurica Maxim

Interactions Between Light Intensity and Phosphorus Nutrition Affect the P Uptake Capacity of Maize and Soybean Seedling in a Low Light Intensity Area

To capture more nutrients, root systems of maize (Zea mays L.) and soybean (Glycine max L.) exhibit morphological and physiological plasticity to a localized supply of phosphorus (P). However, the mechanisms of the interaction between light intensity and P affecting root morphological and physiological alterations remain unclear. In the present study, the regulation of P uptake capacity of maize and soybean by light intensity and localized P supply was investigated in a low solar radiation area. The plants were grown under continual and disrupted light conditions with homogeneous and heterogeneous P supply. Light capture of maize and soybean increased under the disrupted light condition. Plant dry weight and P uptake were increased by more light capture, particularly when plants were grown in soil with heterogeneous P supply. Similarly, both localized P supply and disrupted light treatment increased the production of fine roots and specific root length in maize. Both homogeneous P supply and disrupted light treatment increased the malate and citrate exudation in the root of soybean. Across all of the experimental treatments, high root morphological plasticity of maize and root physiological plasticity of soybean were associated with lower P concentrations in leaves and greater sucrose concentrations in roots. It is suggested that the carbon (C), exceeded shoot growth capabilities and was transferred to roots as sucrose, which may serve as both a nutritional signal and a C-substrate for root morphological and physiological changes

catena-Poly[[μ2-4,4′-bis(pyridin-3-ylethynyl)-1,1′-biphenyl-κ2N:N′]bis(μ2-thiocyanato-κ2N:S)bis(thiocyanato-κS)dimercury(II)]

In the title polymer, [Hg2(SCN)4(C26H16N2)]n, the two equivalent HgII atoms are coordinated by one N atom of a bridging 4,4′-bis(pyridin-3-ylethynyl)-1,1′-biphenyl ligand, two S atoms of two thiocyanates and one N atom of a thiocyanate, giving rise to a distored tetrahedral coordination environment. Two thiocyanate ligands bridge symmetry-related metal atoms to form a polymeric chain extending parallel to [001], and another bridging mode is accomplished by the organic ligand that is located about an inversion centre. The dihedral angle between the coordinating pyridine ring and the benzene ring is 11.4 (2)°, and the two coordinating pyridine rings in the organic ligand are parallel by symmetry. The point group of the ligand in the compound is thus close to C2h. The result of the mode of the organic ligands is the formation of zigzag sheets connected via bridging thiocyanate ligands

Removal characteristics of tetracyclines resistant bacteria and tetracycline resistance genes in sludge deep dehydration

In order to investigate the removal characteristics of Tetracyclines Resistant Bacteria (TRB) and Tetracycline Resistance Genes (TRGs) in sludge deep dehydration,Dilution plate coating method and Real-Time Polymerase chain reaction (RT-PCR) were used to detected the numbers of TRB and four tet genes (tetA、tetB、tetM and tetX) abundant before and after sludge dehydration,and then TRB and TRGs removal characteristics before and after sludge deep dehydration were analyzed.Results showed that:both TRB and TRGs were determined before and after sludge deep dehydration.However,the TRB and TRGs were partly removed after the treatment of sludge deep dehydration.tetA, tetB and tetM removal percentages reached more than 80%.The results can be used as reference for the control of TRB and TRGs contamination

Molecular Dynamics Simulations Based on 1-Phenyl-4-Benzoyl-1-Hydro-Triazole ERRα Inverse Agonists

Estrogen-related receptor α (ERRα), which is overexpressed in a variety of cancers has been considered as an effective target for anticancer therapy. ERRα inverse agonists have been proven to effectively inhibit the migration and invasion of cancer cells. As few crystalline complexes have been reported, molecular dynamics (MD) simulations were carried out in this study to deepen the understanding of the interaction mechanism between inverse agonists and ERRα. The binding free energy was analyzed by the MM-GBSA method. The results show that the total binding free energy was positively correlated with the biological activity of an inverse agonist. The interaction of the inverse agonist with the hydrophobic interlayer composed of Phe328 and Phe495 had an important impact on the biological activity of inverse agonists, which was confirmed by the decomposition of energy on residues. As Glu331 flipped and formed a hydrogen bond with Arg372 in the MD simulation process, the formation of hydrogen bond interaction with Glu331 was not a necessary condition for the compound to act as an inverse agonist. These rules provide guidance for the design of new inverse agonists

The numerical simulation for coal gangue as roadbed material on groundwater nitrate concentration

Numerical simulation was used to elaborate temporal and spatial distribution of nitrate concentration in groundwater under one highway,which was constructed with coal gangue based on experiment.Experimental results indicated that the contaminated area spread around over time,but more obviously in horizontal direction,especially in groundwater flow direction.In addition,nitrate concentration decreased gradually in two-axis direction,and contaminated degree decreased with the increasing of distance from the contaminated source caused leaching solution.Numerical simulation suggests that the nitrate concentration (N) in the section will only meet the standard of class III (GB/T14848-93) for groundwater environmental quality after 10 years,although the concentration reaches the standard of class I currently

Statistical Analysis of Influence of Cover Depth on Loess Tunnel Deformation in NW China

Loess is a kind of special soil with structure and hydrocollapse behavior; due to the particularity of loess, the deformation regularity of the tunnel in loess shows different characteristics from those in rock. To ensure the safety of construction, crown settlement (CS) and horizontal convergence (HC) are widely used to assess the stability of the tunnel structural system. Based on statistical analysis, this study focused on analyzing the influence of cover depth on the deformation of surrounding rock of loess tunnels by ANOVA, and relationships between them were presented by regression analysis. The achieved results indicated that the influence of cover depth on deformation was not obvious in shallow tunnels, while the cover depth had a significant effect on deformation in deep tunnels. Based on the difference of influence of cover depth on deformation between shallow tunnels and deep tunnels, a method for determining the cover depth threshold (CDT) in the tunnel by statistical analysis was proposed. The horizontal and vertical deformations in shallow tunnels were discrete and obeyed the positive distribution, mainly concentrated within 200 mm. The deformation allowance in shallow tunnels was recommended to be 200 mm. In deep tunnels, as the cover depth increased, the deformation increased linearly, while the CS/HC decreased