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The 230Th dating (238U–234U–230Th dating method) has become one of the most important dating methods for Quaternary research. However, the 230Th/232Th ratio of 4.4 ± 2.2ⅹ10−6 is widely used for age correction in 230Th dating method. Here, we collected active speleothems with exactly known age and zero-year-old calcium carbonate from caves and dated them by 230Th dating. Our data indicated that the initial 230Th/232Th ratio can be one order of magnitude higher than the ratio of 4.4 ± 2.2 × 10−6. High initial 230Th/232Th ratio may result in false and comparatively old calculated age than the real age of young samples with low 238U concentration. So, the accurate initial 230Th/232Th ratio of active speleothem deposited in the same cave, instead of the general initial 230Th/232Th ratio, is essential for the precise age correction of young speleothem samples of low 238U concentration. Finally, we proposed a procedure to correlate modern observation and speleothem based paleoclimate reconstruction, on the basis of precise 230Th age which corrected by the true initial 230Th/232Th ratio.

It is conducive to the sustainable development of human beings in karst regions to research the mechanism of karst rocky desertification (KRD) expansion. Whether the large-scale KRD in southwestern China is caused by climate change or human activities is still controversial. In this study, the evolution of the KRD in southwestern China over the past 2000 years was reconstructed through the high-precision δ13C record of stalagmites from Shijiangjun (SJJ) Cave, Guizhou Province, China. The δ13C of the stalagmites from SJJ Cave exhibited heavy values from the Medieval Warm Period (MWP) to the Little Ice Age (LIA). Furthermore, the δ13C records of other stalagmites and tufa from southwestern China also showed the same significant heavy trend. Because the stalagmite δ13C could record the change of ecological environment, it indicated that the consistent change of the stalagmites δ13C may record the process of KRD expansion in the karst regions of southwestern China. During the MWP, the stronger Asian summer monsoon and the northward movement of the rain belt led to a dry period in southwestern China and a wet period in northern China. In contrast, it was wet in southwestern China and dry in northern China during the LIA. In addition, after the Jing-Kang event (JK event, AD1127) occurred at the end of the Northern Song dynasty, the political and economic center of China migrated to southern China for the first time, which changed the population distribution pattern of larger population in the north and smaller population in the south. Therefore, the expansion of KRD in southwestern China was exacerbated in the MWP due to the change of climate in southwestern China, the migration of a large number of people, wars, the large-scale reclamation of arable land, and the cultivation of large areas of crops.

Cave monitoring is an important method to investigate the deposition mechanism and factor influencing the trace elements in drip water and speleothemsThe Mg and Sr concentrations and the Mg/Ca and Sr/Ca ratios and 87Sr/86Sr in drip water and speleothems are often used to explore climate and environmental changes.Systematic monitoring was performed on the Mg and Sr contents, Mg/Sr ratio and 87Sr/86Sr of soil, soil water, cave drip water, and the active speleothems (AS) in Furong Cave in Chongqing, southwest China, during 2009–2018 (A.D). The results were interpreted in conjunction with the changes in the 87Sr/86Sr ratios to explore the main sources and controlling factors of Sr and other trace elements in drip water. (1) Mg and Sr concentrations and 87Sr/86Sr ratios in soil water were increased which was related to the prolonged residence time of water in the soil in winter and spring because of less rainfall. It indicates that the trace element contents of soil water reflect seasonal changes of the rainfall. (2) The Mg and Sr contents were higher in drip water than in soil water, as well as the 87Sr/86Sr ratios of drip water was closer to that of the bedrock, which indicates that the overlying bedrock was the main source of the trace elements in drip water and the speleothems in Furong Cave. (3) Mg contents and Mg/Sr ratios in drip water and AS showed decreasing trend corresponding to the increasing annual rainfall in the monitoring period which resulted in the shorter water-rock contact time. (4) The growth rate of AS may be an important factor to control the Sr contents in AS because of the similar increasing trend. (5) The Mg and Sr contents and the Mg/Sr ratios of drip water and AS did not exhibit seasonal variations due to the mixing of the fissure water and complex hydrology condition of the overlying bedrock, however, the geochemical indexes (Mg and Mg/Sr ratio) showed an opposite trend to the annual rainfall variation. This study suggests that the variations of Mg, Sr and Mg/Sr ratios of drip water and AS can response to the rainfall on the multi-year timescale, which contributes critical insights into the paleoclimate interpretation of proxies of speleothems in the cave with hundreds of meters thick bedrock.

The Asian-Australian monsoon (AAM) system distinctly influences global climate. However, the linkage between ENSO (El Ni~noeSouthern Oscillation) and AAM is still poorly understood over the last millennium. Here, we combined stalagmite d18O (d18Os) records with exceptionally high-resolution and high-precision chronologies to demonstrate a tight remote coupling between AAM and tropical ocean hydrology on the multi-year, decadal, and centennial timescales. Our results reveal that (1) There is a significant negative correlation between the multi-year weighted average precipitation d18O (d18Oaw) from the AAM and Southern Oscillation Index (SOI), providing a modern analogous coupling for linking stalagmite d18O (d18Os) and ENSO over the past 100 years. (2) Over the last millennium, the integrated d18Os record exhibit positive excursions during the Little Ice Age (LIA), marked by a tendency for more El Ni~no-like state conditions in the tropical Pacific, which is consistent in SST-gradient ENSO reconstruction but different to precipitation reconstruction. (3) Wavelet and power spectrum analysis for the integrated d18Os record in the AAM region show that there is a significant multi-year periodicity (2.2, 2.8, 3.5, 4.6 yr), conceding with the ENSO cycle (2e7 yr), whereas, some multi-decadal and centennial cycles (10.1, 17, 28.6, 52.7, 143 yr) are significant too. We provide evidence from instrumental and paleocliamte datasets (GNIP and NOAA) and propose a possible “circulation effect” mechanism responsible for variations of d18Os in the East Asian Monsoon (EAM) and Australian Monsoon (AM) region over the last millennium

Three new tryptamine derivatives diaporols T-V (

Siberia and Central Asia are located at middle to high latitudes, encompassing a large landlocked area of the Eurasian continent and vast tracts of permafrost, which are sensitive to global climate change. Here, we investigated the data from 15 Global Network of Isotopes in Precipitation (GNIP) stations to clarify the relationship between precipitation &delta, 18O (&delta, 18OP) and the local temperature and precipitation amount on the monthly, seasonal, and annual timescales. Three main conclusions as following: (1) On the monthly time scale, the variation in &delta, 18OP is mainly controlled by the &ldquo, temperature effect&rdquo, (2) The weighted average value of precipitation &delta, 18Ow) exhibited &ldquo, over 60&deg, N&ndash, 70&deg, N. However, &delta, 18Ow was dominated by multiple factors from 40&deg, N to 60&deg, N (e.g., the North Atlantic Oscillation (NAO) and water vapor source changes). (3) The variations of &delta, 18OW can be attributed to the changes in pathway of the westerly dominated by the NAO at annual timescale. Therefore, it is possible to reconstruct the histories of past atmospheric circulations and water vapor sources in this region via &delta, 18O in geologic archives, e.g., speleothem and ice core records.

This article proposes a fault tolerance control (FTC) system that composes of a state observer and a static filter, which can eliminate the adverse effects of sensor failures on the active mass damper control system of high‐rise buildings and realize fault detection and isolation. First, the accurate acceleration responses are obtained through a static filter that is used for minimizing the differences between the estimated and actual feedback signals. The key point is transformed into a gain optimization problem solved by a linear matrix inequality approach. Then, a state observer uses the detected and isolated acceleration responses as the feedback signals to estimate the whole states, which are used to calculate the control forces. Finally, a new observer‐based FTC system is accomplished for high‐rise buildings. To verify its effectiveness, the proposed methodology is applied to a numerical example and an experimental system. The results demonstrate that the fault tolerance controller has a good performance and stable control parameters, which provides good potential for structural vibration control of high‐rise buildings.

The scientific explanation of speleothem δ18O in Chinese monsoon region is a greatly debated issue. Modern cave monitoring combined with instrument observation maybe is an essential solution to deal with this issue. During the period from 2011 to 2016, we monitored local precipitation, soil water in three soil profiles, and six drip water sites in Yangkou Cave, which is located in Chongqing City, Southwest China. This article presents measurements about δ18O, δD and Mg/Ca ratios of drip water and compared these geochemical proxies with contemporaneous atmospheric circulations. The main conclusions are: (1) As water migrates from precipitation to soil water to cave drip water, the amplitudes of seasonal variations in δD and δ18O decreased gradually. Due to the existence of complex hydrogeological conditions, the range of variation and the seasonal characteristics of δD and δ18O differ among the drip sites where samples were collected, but the interannual variability is nearly the same. The drip water Mg/Ca ratios are mainly regulated by changes in hydrological conditions in the epikarst zone, with higher values during winter months than that during summer months. (2) When an El Nino event occurs, the Western Pacific Subtropical High (WPSH) is migrated westward, and the production of near-source water vapor from the western Pacific and the South China Sea increases, leading to higher δ18O values in the precipitation and the cave drip water. The drip water Mg/Ca ratios were significantly lower with increased summer precipitation. On the other hand, during La Nina events, the WPSH is migrated eastward, and inputs of water vapor that has traveled greater distances (from the Indian Ocean) become comparatively important, resulting in lower δ18O values in the precipitation and the cave drip water. The drip water Mg/Ca ratios were higher with decreased summer precipitation. In summary, the interannual variability of δ18O in the drip waters of Yangkou Cave reflects changes in water vapor sources caused by atmospheric circulation patterns. Mg/Ca ratios respond to changes of precipitation and CO2 in soil and can be used to reconstruct abnormal drought or flood events.

The geochemical compositions of cave drip water and speleothems such as Mg, Sr, Mg/Ca, Sr/Ca, and 87Sr/86Sr are considered to be responsive to changes in the local climate and hydrological conditions. Systematic monitoring was performed on the Mg and Sr contents, Mg/Sr ratio and 87Sr/86Sr of soil, soil water, cave drip water, and the active speleothems (AS) in Furong Cave in Chongqing, southwest China, during 2009–2018 (A.D). The results were interpreted in conjunction with the changes in the 87Sr/86Sr ratios to explore the main sources and controlling factors of Sr and other trace elements in drip water. (1) Due to the decrease in winter and spring rainfall, the residence time of water in the soil was prolonged, which resulted in increasing of Mg and Sr concentrations and 87Sr/86Sr ratios in soil water. It indicates that the trace element contents of soil water reflect seasonal changes of the rainfall. (2) The Mg and Sr contents were higher in drip water than in the soil water, as well as the 87Sr/86Sr ratios of the cave drip-water was closer to that of the bedrock, which indicated that the overlying bedrock was the main source of the trace elements in the drip water and the speleothems in Furong Cave. (3) Mg contents and Mg/Sr ratios in drip water and AS showed decreasing trend, which may be affected by the shorter water-rock contact time due to the increasing annual rainfall in the monitoring period. (4) The Sr contents in AS might be affected by the growth rate of AS because of the similar increasing trend. (5) The Mg and Sr contents and the Mg/Sr ratios of the drip water and AS did not exhibit seasonal variations due to the mixing of the fissure water and complex hydrology condition of the overlying bedrock, however, the geochemical indexes (Mg and Mg/Sr ratio) showed an opposite trend to the annual rainfall variation. In short, this study highlights the responses of the changes of Mg, Sr contents and Mg/Sr ratios of drip water and AS to the rainfall on the multi-year timescale, which contributes critical insights into the paleoclimate interpretation of proxies of speleothems in the cave with hundreds of meters’ thick bedrock.

Siberia and Central Asia are located at mid- to high latitudes and encompass a large landlocked area of the Eurasian continent containing vast tracts of permafrost (seasonal permafrost and permafrost), which is extremely sensitive to global climate change. However, previous research has scarcely investigated the changes in the paleoclimate in this region. Similarly, the temporal and spatial distributions of the stable isotopic composition (δ18OP) of precipitation and its corresponding influencing factors remain largely unknown. Therefore, we used data from 15 Global Network of Isotopes in Precipitation (GNIP) stations to investigate the relationships between δ18OP and the local temperature and precipitation considering changes in atmospheric circulation. Analyses conducted on the monthly, seasonal and annual timescales led to three main conclusions. (1) At the monthly timescale, the variations in δ18OP exhibited a significant positive correlation with the monthly mean temperature (p temperature effect over 60° N–70° N. However, δ18OW may have been dominated by multiple factors from 40° N to 60° N (e.g., the North Atlantic Oscillation (NAO) and water vapor source changes). (3) At the annual timescale, the variability of the path of the westerly caused by changes in the NAO explained the variations in both δ18OP and δ18OW. Based on the limited observational data in this region, we found that δ18OP is correlated with the local temperature at the monthly and seasonal timescales. However, at the annual timescale, in addition to the temperature effect, δ18OP reflects the variability of the water vapor source that is dominated by the EZCI and NAO. Therefore, it is possible to reconstruct the histories of past atmospheric circulations and water vapor sources in this region via geologic δ18O proxies, e.g., speleothems records.

The frequent alternation between droughts and floods in the karst regions of Southwestern China has a serious impact on the ecological environment and socio-economic development. Although some high-resolution records for this region have been published, there is a lack of multi-proxy geological records that could be used to reconstruct the relationships between the changes in the Asian summer monsoon (ASM) and the regional hydrology and ecological environment since the Late Holocene. In this study, the history of the ASM from 3109 to 694 yr BP with a mean temporal resolution of 2.5 yr is reconstructed based on 47 high-precision 230Th dating results (mean 2-sigma error of ±14 yr), 959 pairs of δ18O/δ13C data, and multiple trace element analyses of a stalagmite from Shijiangjun (SJJ) Cave in the karst area of Southwestern China. The positive δ18O and δ13C excursions accurately recorded eight interdecadal-centennial weak summer monsoon events at ∼779, 1013–911, 1282–1172, 1736–1638, 1961–1864, 2472–2375, 2931–2818, and 3050–3014 yr BP. The cross-wavelet spectrum analysis of the δ18O and δ13C of stalagmite SJJ7 indicates that they have similar periods. The 7 yr period of the δ18O record was determined to have the maximum contribution rate (36.8%) to the periods using ensemble empirical mode decomposition (EEMD) analysis. In the Late Holocene, the weak ASM events were dominated by the southward shift of the Intertropical Convergence Zone (ITCZ) and the frequent El Nino events on an interdecadal-centennial timescale. The southward migration of the ITCZ lead to frequent El Nino events, and the resultant Hadley Circulation and Walker Circulation were weakened, leading to a weak ASM and changes in the hydrological conditions in the monsoon region. The δ13C values of the stalagmite changed relatively slowly compared with the δ18O values, which may indicate that the degradation and restoration of the regional ecological environment caused by abrupt changes in the climate is a relatively slow process. When the summer monsoon decreased, the stalagmite’s Mg/Ca and Sr/Ca ratios were relatively high due to CO2 degassing, and the prior calcite precipitation (PCP)/prior aragonite precipitation (PAP) increased in the karst zone. However, the Mg/Ca ratio increased and the Sr/Ca ratio rapidly decreased during the calcite deposition due to differences in the crystal structures and partition coefficients of aragonite and calcite. The dark layers in stalagmite SJJ7 correspond to transition from heavy to light δ18O values, reflecting the transition in the ASM. The pulsed increases in the elements (Mn, Fe, Al, and Si) in the dark layers reflect the stronger mechanical transport caused by more rainfall. The multi-proxy analysis of this stalagmite may reflect the interactions between the changes in the ASM and the atmosphere-hydrosphere-pedosphere-biosphere-lithosphere in the karst critical zone during the Late Holocene.

Stalagmites are the product of the combined effects of the surface environment and the cave environment, and their stable carbon and oxygen isotope ratios (δ18O and δ13C) have been widely used as proxies for palaeoclimatic and palaeoenvironmental reconstructions. Modern cave monitoring is essential for the accurate interpretation of multiple-proxies in stalagmites. However, the interpretation of the climatic and environmental signals indicated by the carbon and oxygen stable isotopes in stalagmites remains controversial. Based on the ongoing monitoring work of Furong Cave in Southwest China over 12 years (2008-2019 AD) involving a combination of field monitoring and experimental data, the following conclusions were drawn. (1) On the interannual scale, the isotopic fractionation of oxygen in active speleothems (AS) exhibits equilibrium fractionation. On the seasonal scale, the crystallization of a mixture of calcite and aragonite minerals is one of the reasons for the deviation of oxygen isotopic composition from the value expected under equilibrium fractionation. (2) There was a significantly positive correlation between δ18O and δ13C values in the AS, which may have been controlled by climate change rather than dynamic fractionation. (3) Mainly because of the mixing effect in the 300–500 m of bedrock overlying Furong Cave, the δ18O value of the drip water reflected the annual average δ18O value of precipitation. (4) The AS δ18O (δ18OAs) values over the 12-year monitoring records did not show significant seasonal variations but exhibited multiyear trend, which might reflect changes in the external atmospheric circulation and “amount effect” on decadal and longer timescales. Consequently, speleothem δ18O values in Furong Cave can be used for isotope-based palaeoclimate reconstruction.

Climate change during the Little Ice Age (LIA) was characterized by globally widespread but spatiotemporally incoherent cooling with high regional variability. However, the onset, termination, internal structure, and underlying forcing mechanisms of the LIA remain unclear. Here we present a U-Th-dated stalagmite record with an average sampling resolution of 0.8 years and mean age uncertainty less than 4 years from Shijiangjun Cave, Southwest China (SW China). We have characterized the dynamics of the Asian summer monsoon (ASM) on interdecadal to centennial timescales during the LIA at unprecedented accuracy and precision. The onset of the LIA occurred at about 1300 (A.D.) and six weak-ASM events were identified at 1340–1380, 1445–1480, 1520–1540, 1600–1630, 1650–1670, and 1695–1730 (A.D.), respectively. The overall climate variability in Chinese monsoon regions is inconsistent with that in Northwest China (NW China). During the coldest period of the LIA (i.e. after 1500 CE), SW China exhibited a cold and dry pattern, while NW China experienced a cold and wet climate. Moreover, our records from the Asian-Australian monsoon (AAM) region showed coherent changes during the LIA, arguing against the interhemispheric “see-saw” model on interdecadal-centennial timescales. Documented solar minima, lower Northern Hemisphere temperature, and positive phases of PDO and ENSO during the LIA weakened the Asian-Australian summer monsoon, decreasing precipitation throughout the AAM regions.

A number of studies proposed a close link between the climate changes in the Asian summer monsoon (ASM), the Southern Hemisphere (SH), and high latitudes of the Northern Hemisphere (NH). But the mechanisms is still an open question. Although speleothems δ18O records have displayed excellent values in the reconstruction of paleoclimate change at centennial - millennial to orbital timescales, the significance of speleothems δ18O and δ13C is still debatable. Here, a high-precise 230Th dated stalagmite from southwestern China was used to reconstruct the changes of ASM and regional hydrological conditions since the last interglacial (3.6–118.1 ka BP) by the coupled δ18O and δ13C. We found: (1) The EASM and ISM are synchronous changing on the orbital timescale, responding to the change of North Hemisphere summer insolation (NHSI) and high latitude climate change. There is a teleconnection between Antarctic temperature change and ASM through the Mascarene High and the Somali Jet. (2) During MIS 5d, the stalagmite δ18O in Yangzi Cave is nearly 1.5‰ higher than that in MIS 2, the maximum of last glacial. This should be attributed to the different isotopic compositions in moisture source of ISM and EASM, and the dynamic changes of monsoon circulations. (3) From MIS 3 to MIS 2, the ASM showed a “stepped” pattern in weakening, consistent with the decreasing NHSI and increasing global ice volume. (4) The changes in stalagmite δ13C indicated the changes of local hydrological conditions and closely correlated with climate changes revealed by stalagmite δ18O. The effective humidity, which determined by temperature, evaporation, and precipitation, dominated the regional hydrological conditions. The change of effective humidity recorded in stalagmite δ13C by influencing surface biomass and soil CO2-production.

Extracellular signal-regulated kinases are widely expressed protein kinases in neurons, which serve as important intracellular signaling molecules for central plasticity such as long-term potentiation. Recent studies demonstrate that there are two major forms of long-term potentiation in cortical areas related to pain: postsynaptic long-term potentiation and presynaptic long-term potentiation. In particular, presynaptic long-term potentiation in the anterior cingulate cortex has been shown to contribute to chronic pain-related anxiety. In this review, we briefly summarized the components and roles of extracellular signal-regulated kinases in neuronal signaling, especially in the presynaptic long-term potentiation of anterior cingulate cortex, and discuss the possible molecular mechanisms and functional implications in pain-related emotional disorders.

Three new simple trichothecenes, 15-acetyltrichoverrol B (3), 13′-acetyltrichoverrin B (5), and 6′-dehydroxytrichoverrin B (6), along with five known trichothecenes trichodermadienediol B (1), trichoverrol B (2), trichoverrin B (4), and roridins A (7) and D (8), have been isolated from the liquid culture of Myrothecium roridum (strain no. QB-1). The structures of the new compounds were established by comprehensive analysis of 1D- and 2D-NMR data. All the compounds were evaluated for antifungal activity, only compounds 7 and 8 showed significant antifungal activity against the tested fungi (MIC ranged from 10 to 5 μg/ml).

Prompted by the pressing necessity to conquer phytopathogenic infections, the antimicrobial compounds were characterized with bioassay-guided method from the ethanol extract derived from the solid-substrate fermentation of Aspergillus sp. IFB-YXS, an endophytic fungus residing in the apparently healthy leave of Ginkgo biloba L. The aim of this work was to evaluate the antimicrobial activity and mechanism(s) of these bioactive compounds against phytopathogens. Among the compounds, xanthoascin (1) is significantly inhibitory on the growth of the phytopathogenic bacterium Clavibacter michiganense subsp. Sepedonicus with a minimum inhibitory concentration (MIC) value of 0.31μg/ml, which is more potent than streptomycin (MIC 0.62μg/ml), an antimicrobial drug co-assayed herein as a positive reference. Moreover, terphenyl derivatives 3, 5 and 6 are also found to be active against other phytopathogens including Xanthomonas oryzae pv. oryzae Swings, Xanthomonas oryzae pv. oryzicola Swings, Erwinia amylovora and Pseudomonas syringae pv. lachrymans etc. The antibacterial mechanism of xanthoascin (1) was addressed to change the cellular permeability of the phytopathogens, leading to the remarkable leakage of nucleic acids out of the cytomembrane. The work highlights the possibility that xanthoascin (1), an analogue of xanthocillin which is used to be an approved antibiotic, may find its renewed application as a potent antibacterial agrichemical. This study contributes to the development of new antimicrobial drugs, especially against C. michiganense subsp. Sepedonicus.

Five new prenylated diphenyl ethers ( 1 – 5 ), five known ones ( 6 – 10 ), and three xanthones ( 11 – 13 ), together with three anthraquinone derivatives ( 14 – 16 ), were obtained from the mantis-associated fungus Aspergillus versicolor GH-2. Their structures were elucidated on the basis of spectroscopic methods. The (2″ S ) absolute configuration of 1 was assigned by using the modified Mosher ester method. The known compounds 9 and 12 exhibited antibacterial activity against the clinical strain Streptococcus pyogenes with the MIC values of 2.5 and 5.0 μg/mL, respectively.

Three new drimane sesquiterpenoids, astellolides C-E (1-3, resp.), four new drimane sesquiterpenoid p-hydroxybenzoates, astellolides F-I (4-7, resp.), together with two known compounds astellolides A and B (8 and 9, resp.), have been isolated from the liquid culture of Aspergillus oryzae (strain No. QXPC-4). Their structures were established by comprehensive analysis of spectroscopic data. The relative and absolute configurations were determined on the basis of NOESY and CD data, together with single-crystal X-ray diffraction analyses of compounds 1-3. The metabolites were evaluated for their cytotoxic activities, however, no compounds showed a significant cytotoxicity against the tested cell lines at a concentration of 20 μM.

Ten new sesquiterpenoids including six brasilane-type sesquiterpenoids, diaporols J–O (1–6), a 3,6-cycloprecapnellane sesquiterpenoid, diaporol P (7), and three drimane sesquiterpenoids, diaporols Q–S (8–10) were isolated from Diaporthe sp., an endophytic fungus associated with the leaves of Rhizophora stylosa collected in Hainan Province, China. The structures of these compounds were elucidated by extensive analysis of NMR, MS, CD spectra and single crystal X-ray diffraction. Among them, compound 9 exhibited moderate cytotoxicity against the SW480 cell line with an IC50 value of 8.72 ± 1.32 μM.

Ribosylation is a significant modification conferring new complex and broadened cellular roles of compounds, but small organic molecules are rarely ribosylated. Here, we report the 3-O- and 4′-O-α-ribosylation of resveratrol, a phytoalexin that is exogenous to the fungus Daldinia eschscholzii IFB-TL01. The ribosylation is mechanistically due to the resveratrol-activated expression of the silent or less active fungal genes governing the ribosylation of non-fungal phytophenols. The resveratrol-induced ribosylation is also characterized by an increased expression of ribosyltransferases in concert with a rare ribosylating reaction using nicotinamide mononucleotide (NMN) as a ribose donor. The ribosylation-reduced toxicity of resveratrol to D. eschscholzii, along with the involvement of at least two p-glycoproteins in the glycosylation, suggests that such a glycosylation process may be a general strategy for the fungal detoxification of phenolic chemicals. The findings present an updated view of the ribosylation of small molecules, and provide direct chemogenetic evidence that will aid understanding of how phytophenols such as resveratrol function differently in the plant, microbial and animal kingdoms.

The Pictet–Spengler (PS) reaction constructs plant alkaloids such as morphine and camptothecin, but it has not yet been noticed in the fungal kingdom. Here, a silent fungal Pictet–Spenglerase (FPS) gene of Chaetomium globosum 1C51 residing in Epinephelus drummondhayi guts is described and ascertained to be activable by 1-methyl-l-tryptophan (1-MT). The activated FPS expression enables the PS reaction between 1-MT and flavipin (fungal aldehyde) to form “unnatural” natural products with unprecedented skeletons, of which chaetoglines B and F are potently antibacterial with the latter inhibiting acetylcholinesterase. A gene-implied enzyme inhibition (GIEI) strategy has been introduced to address the key steps for PS product diversifications. In aggregation, the work designs and validates an innovative approach that can activate the PS reaction-based fungal biosynthetic machinery to produce unpredictable compounds of unusual and novel structure valuable for new biology and biomedicine.

To investigate the influence of granulocyte growth factor in uterine perfusion on the pregnancy outcome of patients with failure of embryo implantation for unknown reason. Then, 68 patients with failure of embryo implantation for unknown reason were enrolled in our hospital from November 2013 to February 2015, which were divided into observation group and control group by random (34 patients in each group). Patients in observation group received basic treatment for granulocyte growth factor in uterine perfusion on the next day, while patients in control group received basic treatment with placebo. Then, endometrial preparation, adverse reaction and pregnancy outcome of patients were compared between the two groups. Comparing the endometrial preparation and average endometrial thickness of patients in control group (9.87±2.12) with those in observation group [(9.87±2.12), there is no significant difference (P0.05). After treatment, patients in both groups performed diabetes, hypertension and other pregnancy complications without difference of statistical significance (P0.05). The embryo implantation rate and clinical pregnancy rate of patients in observation group were significantly higher than those in control group [(82.35%) and (44.12%) vs (52.94%) and (17.65%)]. Moreover, the live birth rate of patients in observation group performed significantly higher than that in control group [(41.18%) vs (14.71%)] with significant difference (P0.05). By taking treatment of granulocyte growth factor, patients with failure of embryo implantation can effectively improve clinical pregnancy rate and embryo implantation rate without severe complication. Therefore, treatment of granlocyte growth factor can improve the pregnancy outcome of patients.

Phytochemical investigation of the stem wood of Dipterocarpus alatus led to the isolation and characterization of four new oligostilbenoids, dipterocarpols A–D ( 1 – 4 ), together with two known resveratrol oligomers, hopeahainol ( 5 ) and hopeafuran ( 6 ). The structures of the new compounds were determined by comprehensive spectral analysis including 1D and 2D NMR, and high-resolution MS. The absolute configurations were determined by NOESY and CD spectra. Dipterocarpol A ( 1 ) and hopeahainol A ( 5 ) showed moderate acetylcholinesterase inhibitory activity with IC 50 values of 8.28 µM and 11.28 µM, respectively. Furthermore, the discovery of compound 3 gave the first evidence that the biosynthetic origin of resveratrol aneuploids is related to the loss of a half resveratrol unit by oxidative cleavage.

In a search for naturally occurring antibacterial compounds in medicinal plants, six hitherto unknown thiophene acetylenes, named 10,11-threo-xanthopappin D, 10,11-erythro-xanthopappin D, 10,11-cis-xanthopappin B, 5-(but-4-chloro-3-hydroxy-1-ynyl)-2-(Z)-pent-3-ene-1-ynylthiophene, 5-(but-4-chloro-3-hydroxy-1-ynyl)-2-(E)-pent-3-ene-1-ynylthiophene, 5-(but-3,4-dihydroxy-1-ynyl)-2-(Z)-pent-3-ene-1-ynylthiophene and two furanosesquiterpenes, as well as fifteen known compounds, were isolated from Xanthopappus subacaulis, which has been used as a traditional Tibetan medicine in China. A biosynthetic pathway to thiophene acetylenes was proposed and, the isolated compounds were tested for their antibacterial activity against five bacteria. Within the series of thiophene acetylenes tested, 10,11-threo-xanthopappin D with a threo configuration exhibited strong activity against Bacillus subtilis, with a minimum inhibitory concentration (MIC) of 7.25μg/mL, whereas 10,11-erythro-xanthopappin D with erythro configuration possessed broad-spectrum antibacterial activity against Escherichia coli, Bacillus cereus, Staphylococcus aureus and Erwinia carotovora, with MICs of 12.5, 15.5, 7.25 and 7.25μg/mL, respectively. Meanwhile, the compounds 10,11-cis-xanthopappin B, xanthopappin B, 5-(but-4-chloro-3-hydroxy-1-ynyl)-2-(Z)-pent-3-ene-1-ynylthiophene and 5-(but-4-chloro-3-hydroxy-1-ynyl)-2-(E)-pent-3-ene-1-ynylthiophene substituted with a Cl atom at C-14 showed moderate inhibitory activity against E. coli, B. cereus, S. aureus, E. carotovora and B. subtilis, with MICs ranging from 31.25 to 62.5μg/mL. The structures of these compounds were elucidated through the comprehensive analysis of spectroscopic data, including UV, IR, MS and NMR.

First, unearth the connotation of well-being of peoples livelihood in the re-development of urban old settlements, to discuss the ways of achieving housing rights based on the concept of well-being of peoples livelihood and analyze the necessity of re-development of urban old settlements under well-being of peoples livelihood. Based on the above research, follow the goal and principle of well-being of peoples livelihood, explore the ways of returning well-being of peoples livelihood to homing position in the re-development of urban old settlements, and guarantee the realization of housing right of residents to promote the equitable distribution of social resources for housing in re-development.

In the redevelopment of current old urban housing area, the benefits and living needs of the disadvantaged are neglected and the problems of space disorder, unbalanced interests, context deconstruction and wasting of resources are prominent. Starting from peoples livelihood happiness, the author discusses the connotation and meaning of peoples livelihood happiness, analyzes the problems of existing in the redevelopment of current old urban housing area, and then proposes the thinking on redevelopment of old urban livelihood housing area under this value guidance, that is to adhere to the core objective of people-first and paying attention to happiness perception and benefit realization of the disadvantaged.

Five new stilbenolignans, hopeachinols E–I (1–5), and two new stilbenoids, hopeachinols J and K (6 and 7), together with the known resveratrol trimer, vaticanol A (8), were isolated from the stem bark of Hopea chinensis. The structures and relative configurations of these natural products were elucidated by using spectroscopic and spectrometric methods. The (8R) absolute configuration of 1 was assigned by using the modified Mosher ester method. Hopeachinols E–I (1–5) possess unprecedented stilbenolignan skeletons, in which a stilbene trimer is linked with a phenylpropanoid unit through a pyran bridge. Hopeachinols J and K (6 and 7) have new skeletons in which a stilbene trimer is connected by an additional two-carbon unit through a furan moiety. An evaluation of the cytotoxicities against HCT116, MDA-MB-231, SMMC-7721, and HepG2 cell lines of the new hopeachinols showed that 1, 2, 4, and 6 have moderate activities with IC50 values in the 10.39–18.72 μM range.

The present study was designed to examine the anti-hyperuricemic and anti-inflammatory effects and possible mechanisms of vaticaffinol, a resveratrol tetramer isolated from ethanol extracts of Dipterocarpus alatus, in oxonate-induced hyperuricemic mice. At 1 h after 250 mg·kg-1 potassium oxonate was given, vaticaffinol at 20, 40, and 60 mg·kg-1 was intragastrically administered to hyperuricemic mice once daily for seven consecutive days. Vaticaffinol significantly decreased serum uric acid levels and improved kidney function in hyperuricemic mice. It inhibited hepatic activity of xanthine dehydrogenase (XDH) and xanthine oxidase (XOD), regulated renal mRNA and protein levels of urate transporter 1 (URAT1), glucose transporter 9 (GLUT9), organic anion transporter 1 (OAT1), organic cation transporter 1 (OCT1), OCT2, organic cation/carnitine transporter 1 (OCTN1), and OCTN2 in hyperuricemic mice. Moreover, vaticaffinol markedly down-regulated renal protein levels of NOD-like receptor 3 (NLRP3), apoptosis-associated speck-like (ASC), and Caspase-1, resulting in the reduction of interleukin (IL)-1β, IL-18, IL-6 and tumor necrosis factor-α (TNF-α) levels in this animal model. Additionally, HPLC and LC-MS analyses clearly testified the presence of vaticaffinol in the crude extract. These results suggest that vaticaffinol may be useful for the prevention and treatment of hyperuricemia with kidney inflammation.

5-amino-tetrazolo[1,5-a]pyrimidin-7-ol (I) was synthesized by reaction of 5-amino-tetrazole with ethyl cyanoacetate in excellent yield. A series of novel 5-amino-6-arylazotetrazolo[1,5-a]pyrimidin-7-ol dyes were prepared by linking o-, m-, p-anisidine, o-, m-, p-chloroaniline, o-, m-, p-nitroaniline, o-, m-, p-toluidine and aniline to 5-amino-tetrazolo[1,5-a]pyrimidin-7-ol (I). The structure of these dyes were confirmed by UV-vis, FTIR and 1H NMR spectroscopic techniques and elemental analysis. The effect of varying pH and solvent upon the absorption ability of 5-amino-6-arylazotetrazolo[1,5-a]pyrimidin-7-ol sudstituted with electron-withdrawing and electron-donating groups at their o-, m-, p-position was examined.

This design is designing for metering system of the beer barrel liquid filling machine. It contains the selection of metering mode and the design of the weighing system mainly etc. The new connection method which is applied multiple weighing sensor constitute the half-bridge measurement circuit which can achieve measuring function of the full-bridge measurement circuit. Not only can this structure increase the stability and shock resistance of the load-bearing platform but also it can solve the problem that generated large error when a single weighing sensor was measuring the object which has different centre of gravity. And this can improve the filling accuracy greatly.

Phytochemical investigation on Fritillaria pallidiflora led to the isolations of one new steroidal alkaloid, (20R,22R,23R,25R)-3β,23-dihydroxy-N-methyl-veratram-13(17)-en-6-one ( 14 ) and fifteen known compounds: five steroidal saponins ( 1 – 5 ), three phenolic glucosides ( 6 – 8 ), three nucleoside compounds ( 9 – 11 ), one amino acid ( 12 ), four steroidal alkaloids ( 13 – 16 ). Compounds 12 , 14 were isolated from F. pallidiflora for the first time. Compounds 1 – 6 were isolated from the genus Fritillaria for the first time and compounds 7 – 8 were isolated from the family Liliaceae for the first time. The chemotaxonomic significance of these compounds was summarized.

Three new polyketides, named daldinone F (1), nodulisporin G (2), and dalmanol C (3), together with five known compounds, 4-8, were isolated from cultures of Daldinia eschscholzii. The structures of the new compounds were elucidated by extensive NMR and MS analyses. Compound 1 showed moderate cytotoxic activity against SW480 cancer cells with an IC50 value of 9.59 μM, and its absolute configuration was determined by single crystal X-ray diffraction.

The nature of uncertainty inference is to give evaluations on inclusion relationships by means of various measures. In this paper we introduce the concept of inclusion degrees into rough set theory. It is shown that the lower approximations of the rough set theory in both the crisp and the fuzzy environments can be represented as inclusion degrees.

Five new steroidal saponins, Pallidifloside D ( 1 ), Pallidifloside E ( 2 ), Pallidifloside G ( 5 ), Pallidifloside H ( 6 ) and Pallidifloside I ( 7 ), together with seven other steroidal saponins ( 3 , 4 , 8 – 12 ) were isolated from the dry bulbs of Fritillaria pallidiflora Schrenk. Their structures were established by spectroscopic techniques (IR, MS, 1D and 2D NMR) and chemical means. The isolated steroidal saponins were evaluated for cyotoxic activity against human C6 brain gliomas and Hela cervix cancer cell lines using MTT assays. Compounds 1 , 10 , 11 , 12 showed cytotoxicity against C6 and Hela cell lines with IC 50 values in the range of 5.1–75.8 μM.