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Recently, an algorithm of surface turbulent heat fluxes over snow/sea ice has been developed based on the theory of maximum entropy production (MEP), which is fundamentally different from the bulk flux algorithm (BF) that has been used in sea ice models for a few decades. In this study, we first assess how well the MEP algorithm captures the observed variations of turbulent heat fluxes over Arctic sea ice. It is found that the calculated heat fluxes by the MEP method are in good agreement with in-situ observations after considering the absorption of incoming radiation in a snow/ice surface layer with infinitesimal depth. We then investigate the effects of two different schemes (MEP vs. BF) in the sea ice model of CICE6 on simulated turbulent heat fluxes and sea ice processes in the Arctic Basin. Our results show that the two different schemes give quite different representations of seasonal variations of heat fluxes, particularly for sensible heat fluxes in summer. The heat fluxes simulated by the MEP produce weak cooling effect on the ice surface in summer, whereas the BF generates a warming effect. As a result, compared to the BF, the MEP leads to a reduced seasonal cycle of Arctic sea ice mass flux by modulating snow-to-ice conversion, basal ice growth, surface ice melt and basal ice melt.

The occurrence of asthma is closely related to environmental factors such as cigarette smoke (CS), one of the common risk factors. Environmental stimuli have the potential to activate transient receptor potential ankyrin 1 (TRPA1) and cause or aggravate asthma. The destruction of tight junctions (TJs) between airway epithelial cells by environmental stimuli in asthma has been researched. It is worth exploring whether CS can injury TJs and aggravate asthma by activating TRPA1. The objective of this study was to investigate the aggravation of CS on ovalbumin (OVA)-induced asthma related phenotypes and TJs expression in mice, and to explore the relationship between TRPA1 and the expression of TJs protein. Female wild type (WT) C57BL/6 mice, induced by OVA, CS and OVA plus CS (OVA + CS) respectively, were used to establish a 42-day asthma model, and mice with TRPA1 knockout (TRPA1−/−) were treated in the same way. This study detected the number of inflammatory cells in peripheral blood and bronchoalveolar lavage fluid (BALF), the levels of IL-4, IL-5, IL-13 in BALF, enhanced pause (Penh) of lung function, pathological changes and the gene and protein expressions of TRPA1 and TJs (including ZO-1, Occludin and Claudin-2) in lung tissues. Compared with normal saline (NS) group, WT mice in the OVA group and OVA + CS group were significantly higher in asthma related phenotypes. The WT-OVA + CS group also showed higher Penh value, levels of IL-5 and IL-13 in BALF and lung tissue injury scores when compared with the WT-OVA group and WT-CS group. However, WT-OVA + CS group mice had significantly larger number of neutrophils in BALF than the WT-OVA group, and had larger number of eosinophils in peripheral blood and higher levels of IL-4 in BALF than the WT-CS group. Meanwhile, compared with the WT-NS group, the expressions of TRPA1 and Claudin-2 in lung tissues increased in other three groups while their expressions of ZO-1 and Occludin decreased, among which, the WT-OVA + CS group showed more remarkable changes. Compared with the WT-OVA + CS group, mice in the TRPA1−/−-OVA + CS showed a significant decrease in the number of inflammatory cells, levels of IL-4, IL-5 and IL-13 in BALF, Penh value and lung tissue injury score, and a downregulation of Claudin-2 expression while an upregulation of ZO-1 and Occludin expressions. In addition, the airway inflammation and injury, and the expressions of ZO-1, Occluding and Claudin-2 expressions were found with no statistic differences between TRPA1−/−-OVA group and TRPA1−/−-OVA + CS group. These results suggest that CS has aggravated the airway inflammation, pathological damage and destruction of TJs in airway epithelium of OVA-induced asthmatic mice, the processes of which are related to the increase of TRPA1 expression.

Temperature-driven baseline is highly responsive to anomalous structural behavior of long-span bridges, which means that the discrepancy between the measured and forecasting temperature-induced strain (TIS) can be examined for anomalies. In this regard, it is important to guarantee the accuracy of the forecasting TIS responses for reliable assessment of structural performance. Bayesian dynamic linear model (BDLM) has shown a promising application in the field of structural health monitoring. Traditionally, BDLM is used to forecast structural responses by utilizing its trend form, seasonal form, regression form, or combination of the three forms. However, different features of time series cannot be totally captured by these forms, which would undermine the accuracy of BDLM. To improve the computational accuracy, an improved BDLM, which considers an autoregressive (AR) component in addition to the trend, seasonal and regression components, is presented in this paper. Specifically, the AR component is able to model the component which cannot be captured by other three components. The real-time monitoring data collected from a long-span cable-stayed bridge is utilized to demonstrate the feasibility of the improved BDLM-based method. In particular, the present BDLM-based method allows for probabilistic forecasts, offering substantial information about the target TIS response, such as mean and confidence interval. Results show that the improved BDLM is capable of capturing the relationship between temperature and TIS. Compared to the AR model, multiple linear regression (MLR) model and BDLM without the AR component, the improved BDLM shows better forecasting performance in modeling and forecasting the TIS of a long-span bridge.

Endogenous electric fields (EFs) direct the migration (electrotaxis) of keratinocytes in skin wounds, and the exogenous application of EFs may therefore improve wound healing, but the potential benefits are limited by the side effects of constant direct current (DC) passing through tissues. In contrast, with pulsed DC (characterized by intermittent output), parameters can be adjusted to minimize the adverse effects of electric currents. However, it remains unknown whether pulsed DC can reliably induce keratinocyte electrotaxis. In this study, using primary keratinocytes in an electrotaxis chamber, we found that a pulsed DCEF at physiological strength (EF = 150 mV/mm, duty cycle = 60%, frequency = 0.1 Hz) could induce robust electrotaxis. This effect was dependent on both voltage and duty cycle, but not on frequency. As predicted, fewer electrochemical reactions and cytotoxic reactions were detected with pulsed DCEF than with constant DCEF. In summary, we here demonstrate for the first time, that pulsed DCEF can trigger keratinocyte electrotaxis comparable to that induced by constant DCEF, while minimizing the electrochemical side effects. These findings support the future development of a pulsed DCEF device to improve wound healing in human patients.

The deltaic and lacustrine sediments, respectively in the syn- and post- rift stages, are recorded during the Cretaceous at the Wulan-Hua Sag, Erlian Basin, Inner Mongolia. In this study, the Mesozoic depositional system and sequence stratigraphic framework are recognized in the Wulan-Hua sag using core, well-log and seismic data. Five sedimentary facies have been identified including fan-delta, braided delta, shallow-lacustrine, deep-lacustrine, and sublacustrine-fan during Cretaceous at the Wulan-Hua Sag. One first-order sequence (MSQ1), three second-order sequences (SSQ1, SSQ2, and SSQ3), and five third-order sequences (SQ1, SQ2, SQ3, SQ4, and SQ5) are classified by subaerial unconformities along the basin margins and correlative conformities in the central part of the basin. During the depositional period of SQ1, SQ2, and SQ3, the depocenter controlled by lake-level fluctuations migrated from southern to northern part companying with multiple- to single-provenance supplies. The characteristics of sedimentary facies and sequence stratigraphy in the Wulan-Hua sag are commonly controlled by faults, provenance and depocenters. The development of the third-order sequences is dominated by tectonism and sediment supplies, as well as lake-level changes driven by climate. The favorable targets for hydrocarbon located in the lowstand system tract of SQ1, SQ2 and SQ3 at the southern parts of the Wulan-Hua Sag.

Objective Recent epidemiological studies have investigated the associations between the use of bisphosphonates and the development of endometrial cancer and ovarian cancer; these studies have shown controversial results. Hence, this meta-analysis was conducted to evaluate the changes in the risks of developing endometrial and ovarian cancers after using bisphosphonates based on current evidence. Methods A comprehensive search was performed in the MEDLINE, EMBASE, and Web of Science databases through January 2017. The summary relative risk (RR) estimates for the effects of the use of bisphosphonates on the risks of developing endometrial and ovarian cancers were calculated using a random-effects model. Results Seven studies were included with a total of 6471 endometrial cancer cases (7 studies with 213,920 participants) and 6783 ovarian cancer cases (4 studies with 105,507 participants). This meta-analysis suggested that any use of bisphosphonates was associated with a significant 27% reduction in the risk of endometrial cancer (RR = 0.73, 95% CI: 0.58–0.93, P = 0.012), but the reduction in the risk of ovarian cancer (RR = 0.81, 95% CI: 0.58–1.14, P = 0.227) was not significant. The protective effects of the use of bisphosphonates against endometrial cancer are mainly found in postmenopausal women (RR = 0.53, 95% CI: 0.34–0.93, P = 0.012) or in those who have taken bisphosphonates for longer than 1 year (RR = 0.57, 95% CI: 0.35–0.93, P = 0.024). Conclusion This meta-analysis suggests that the use of bisphosphonates is associated with a reduction in the risk of endometrial cancer but not ovarian cancer.

Nine-year data were collected to analyze the occurrence of rice planthoppers in diversified farming on Chongming Eco-Island in China from 2006 to 2014, the most important pests of rice in agroecosystems. We found a significantly linear decrease in the average numbers of adult rice planthoppers trapped per light trap per day. Using quadratic regression polynomial analysis we concluded that four meteorological indicators (average daily temperature, daily rainfall, sunshine duration, and average daily wind velocity) had significant effects on the numbers of brown planthopper ( Nilaparvata lugens ) and white-backed planthopper ( Sogatella furcifera ) trapped in the lamp, and that average daily temperature had a significant effect on the number of small brown planthopper ( Laodelphax striatella ) trapped in the lamp. These findings suggest that increasing temperature related to climate change might promote the occurrence of rice planthoppers in diversified farming in the future.

It is shown that ReaxFF molecular dynamics simulations (MDSs) can be used to study the high temperature gasification of glucose in supercritical water under microwave heating. At the early stage of gasification, yields of gas products have great difference under microwave and conventional heating models. It is considered that the difference results from the non-thermal effect of microwave. Therefore, simplified pathway model of free radical reactions is further constructed to study the influences of external electric fields on the yields of hydrogen gas, carbon monoxide and intermediate formaldehyde. Rotation characteristics of water and carbon monoxide electric dipoles are also studied at a high temperature. To analyze the impacts of external electric fields on the water-gas shift reactions, collision theory is introduced and several simplified collision models are constructed and detailed. Based on our studies, for the first time, it is concluded that using microwaves as heating source is feasible to the gasification of glucose in supercritical water, where no obvious thermal runaway is found. Moreover, the external microwave can increase the production of hydrogen gas through promoting the yields of glucose decomposed into formaldehyde and hydrogen free radical.

Polyphenols (flavonoids and anthraquinones) are one of the most important phytochemicals in Fagopyrum tataricum L. Gaertn. (tartary buckwheat). However, the relationship between the polyphenols of tartary buckwheat seeds and their morphological variations is unclear. We developed a liquid chromatography-mass spectrometry-based targeted metabolomics method to study the chemical profiles of 60 flavonoids and 11 anthraquinones in 40 seed cultivars (groats and hulls). Both flavonoids and anthraquinones were related to variations in seed color; the fold change from yellowish-brown to black seeds was 1.24-1.55 in groats and 0.26-0.76 in hulls. Only flavonoids contributed to significant differences in seed shape; the fold change from long to short seeds was 1.29-1.78 in groats and 1.39-1.44 in hulls. Some differential metabolites were identified at higher concentrations in hulls than in groats. This study provides new insights into differences in polyphenols among tartary buckwheat seeds with different color and shape.

Strong winds could cause train derailment and truck rollover which may result in service interruption, serious injury, and even loss of life. The wind-induced accident is highly related to the maximum value of short-term wind speed, thus highlighting the importance of regulating the vehicle velocity based on wind gusts. Accurate prediction of wind gusts is essential to control the vehicle velocity ahead of time, thereby reducing the risk of accidents. The majority of existing approaches focus on the prediction of mean wind speed. In contrast, fairly limited research applies the machine learning model to forecast wind gusts with strong time-varying characteristics and volatility. In this study, a probabilistic approach is presented to forecast wind gusts using ensemble learning. The ensemble model includes three machine learning models, namely, random forest (RF), long-short term memory (LSTM), and Gaussian process regression (GPR) model. The proposed probabilistic approach allows for the quantification of uncertainty in prediction of wind gusts. The feasibility of the ensemble model is illustrated by using the field wind measurements acquired from a long-span cable-stayed bridge. Compared to the persistence, RF, LSTM, GPR, averaging, and gradient boosting decision tree models, the proposed ensemble model exhibits higher accuracy and generalization performance.

Poly- and perfluorinated compounds (PFCs) may induce potential endocrine-disrupting hormonal effects. However, the molecular mechanism of the toxicology of PFCs remains unclear, and the insufficient information is available on the biological activities of PFCs at present. In this study, the cell-based reporter gene assays were used to determine the agonistic activity of PFCs on the human pregnane X receptor (hPXR). The heuristic method combined with best subset modeling (HM-BSM) based on Dragon descriptors and comparative similarity indices analysis (CoMSIA) were employed to build classical quantitative structure-activity relationship (QSAR) and three-dimensional QSAR models, respectively. The applicability domain (AD) of the classical QSAR model was assessed. Both the HM-BSM and CoMSIA approaches demonstrated good robustness, predictive ability, and mechanistic interpretability. The r2 and leave-one-out cross-validation squared correlated coefficient (q2LOO) values were 0.872 and 0.759 for the HM-BSM, and 0.976 and 0.751 for the CoMSIA model, respectively. The hPXR agonistic activity of the PFCs predicted by the built HM-BSM and CoMSIA agreed well with experimental activity, with root mean square error (RMSE) values of 0.0803 and 0.117, respectively, and external validation squared correlated coefficients (q2EXT) of 0.972 and 0.932, respectively. The hPXR agonistic activity of PFCs was related to their molecular polarizability, charge and atomic mass. Hydrogen bonding and hydrophobic interactions constituted the primary intermolecular forces between PFCs and the hPXR. The developed models were used to screen the PFCs with high hPXR agonistic activity.

The extensive input of chemical insecticides for pest control is considered as a serious risk to the environment, and the ecological disturbance of chemical insecticides has both positive and negative effects on complex agro-ecosystems. This paper proposed an indicator based on ecological two-sidedness theory and Shannon entropy, which is intended for analyzing informational complexity in a decision network of the chemical insecticide pollution management. The results indicated that the order of the value of R CC/CP index (where the R CC/CP index matrix W CC/CP is defined as the index optimization matrix of comprehensive cost divided by the index optimization matrix of comprehensive profit) for three insect pest-controlling strategies in scallion fields was “applying frequency vibration lamps and environment-friendly insecticides 8 times” (0.8714)

An extended mobile lattice gas model with consideration of the pedestrian’s variable walking step size is proposed in this paper. The model first scans various possible step sizes and then determines the movement directions in terms of probabilities which consider the step size factor. Simulation results from a room with one exit show that pedestrians with variable step size can evacuate more quickly than those with fixed step size. The proposed model is applied in a real situation where passengers move in channels of a subway station for line transfer or evacuation. We also investigate four commonly used flow management measures and discuss their effectiveness.

The Wulan-Hua Sag in the south of Erlian Basin has large oil and gas resource, whereas the source rocks genetic potential and oil-rock correlation in its Aershan Formation (K1ba) and First member of Tengge'er Formation (K1bt1) are still unclear. We performed organic geochemistry analyses of oil and mudstone samples to divide crude oil types, evaluate source rock potential, and establish relatively accurate oil-source correlation. The results indicate that the source rocks in K1ba and the Lower interval in First member of Tengge'er Formation (LK1bt1) belong to good source rocks, characterized by high organic matter abundance, oil-prone kerogen type, and relatively high thermal maturity. K1ba and K1bt1 crude oil samples were divided into two types sourced from different Wulan-Hua source rocks. Type A oil is distributed in the K1ba and LK1bt1 of Saiwusu uplift and Hongjing uplift, and featured by a low gammacerane amounts (the majority of gammacerane/C30H 0.3), and low Pr/Ph (ranging from 0.38 to 0.76, with mean value of 0.63). Its organic matter includes dominant terrestrial plant source, and this oil type should be sourced from the LK1bt1 source rocks in the Saiwusu uplift.

Non-expressor of pathogenesis-related genes 1 (NPR1) plays a significant role in the defense responses of plants to pathogens by regulating the expression of defense-related genes. In the present study, we isolated two NPR1 genes from Vitis aestivalis cv. Norton and Vitis vinifera cv. Cabernet Sauvignon, which were referred to as VaNPR1.1 and VvNPR1. 1-CS, respectively. They encode a protein of 584 amino acids with a predicted molecular weight of 64.8 kDa and a theoretical isoelectric point (pI) of 5.74. The predicted amino acid sequences of VaNPR1.1 and VvNPR1.1-CS differ by only one amino acid. Over-expression of VaNPR1.1 gene in Arabidopsis npr1-1 mutant plants restores the transcriptional expression of AtPR-1 gene, though not to the full scale. This result demonstrated that a grapevine VaNPR1.1 possesses a similar function to the Arabidopsis NPR1 in the regulation of defense-related genes. Over-expression of VaNPR1.1 in transgenic Arabidopsis plant increased tolerance to salinity, but had no effect on the drought tolerance. We conclude that VaNPR1.1 is a functional ortholog of AtNPR1 and also involved in grapevine's response to the salt stress.

Objective To evaluate the effect of vitrification of mouse oocytes on the behavior of adult offspring. Study design Oocytes from mice were vitrified, warmed and inseminated, and two-cell embryos were transferred to foster mothers. The behavioral characterization of the offspring was detected by the Morris water maze test, forced swimming test, and elevated plus maze test, and compared to that of offspring from fresh oocytes. Results Offspring produced by vitrified oocytes showed normal motor function. In the Morris water maze test of spatial learning there was a slightly decreased time spent in the quadrant containing the platform relative to mice from fresh oocytes, but the difference did not reach statistical significance. In addition, offspring from vitrified oocytes did not exhibit alterations in emotional behavior. Conclusion No alterations were found in the behavioral characterization of adult offspring from vitrified oocytes compared with those from fresh oocytes.

Experiment was conducted at the Gongzhuling Experimental Station of Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Jilin Province, China, during 2009–2010. Six representative varieties of maize (Baihe in the 1950s, Jidan 101 in the 1960s, Zhongdan 2 in the 1970s, Yedan 13 in the 1980s, Zhengdan 958 in the 1990s, and Xianyu 335 in the 2000s) were each planted under two different densities (52 500 and 82 500 plants ha−1) and two different nitrogen application levels (150 and 300 kg ha−1). Root characteristics and distribution among soil layers were studied by the field root digging method. The results showed that root mass increased with the process of the growth and development of the plant, and it peaked at kernel filling stage, and decreased at maturity due to the root senesces. Root mass of different maize varieties from the 1950s to 1980s had a trend of increase, while it decreased for the modern varieties. Root length and root surface areas had the similar changing trend. The study suggested that early maize varieties may have root redundancy, and reducing root redundancy may be a direction for variety improvement for high yield. Root characteristics were affected by nitrogen application level and density; modern varieties were more suitable for higher fertilizer application level and density conditions. Root characteristics distribution among soil layers decreased by an exponent equation, but the regression coefficients of different varieties were different. Though the root length density (RLD) of every soil layer of different varieties also decreased by an exponent equation, there were large variations of RLD in every part of a layer.

The network topology and metabolic fluxes of central carbon metabolism in the industrial vitamin B-12 producing strain Pseudomonas denitrificans were characterized under oxygen limiting levels. Cultivations were carried out with 100% [1-C-13] or 20% [U-C-13] glucose as substrates under different oxygen supply conditions. The labeling patterns of the proteinogenic amino acids of exponentially growing cells were used to accurately estimate the fluxes in the central carbon metabolism of P. denitrificans. Metabolic flux analysis showed that glucose was mostly catabolized by the Entner-Doudoroff and pentose phosphate pathways. Up to 33% of glucose was consumed via the PP pathway under high specific oxygen uptake rate (SOUR) conditions. This amount was 77.9% higher than that under low oxygen uptake conditions. Quantitative evidence was also found for reversible serine hydroxymethyl transferase and threonine aldolase activities. Metabolic flux and cofactor analyses further showed that higher SOUR accelerated the supply of precursors and methyl groups. SOUR also provided more NADPH for higher vitamin B12 production under the same glucose consumption.

A 5.4-kilobase mRNA, the expression of which is down-regulated after treatment of human peripheral blood mononuclear cells (PBMCs) with various T cell-activating agents, was isolated using an mRNA differential display method. Nucleotide sequence analysis identified the 5' end of this RNA as human retinoid receptor RXRalpha mRNA. Here, we report the nucleotide sequence of 3.6 kilobases of this RNA, which represents the 3' end of RXRalpha mRNA, the sequence of which has not been previously described. Activated PBMCs also expressed lower levels of RXRalpha protein, and a DNA binding assay showed that the activation-induced loss of RXRalpha mRNA and protein expression correlated with the loss of DNA binding activity of this protein. We present evidence that the transition from G0/G1 to S phase of the cell cycle results in the down-regulation of RXRalpha expression and that cell cycle inhibitors, which block the cells in G1 phase, prevent this down-regulation. The decrease in the levels of RXRalpha mRNA was found to be regulated at the post-transcriptional level and involved new protein synthesis. These observations indicate that the levels of RXRalpha expression in T lymphocytes are coupled to cell cycle progression, and there is tight regulatory control of RXRalpha expression during the transition from G0/G1 to S phase of the cell cycle.

We recently cloned a full-length DNA copy of the dengue type 4 virus genome. Analysis of the 5' terminal nucleotide sequence suggested that the three-virion structural proteins are synthesized by proteolytic cleavage of a polyprotein precursor which is encoded in one open reading frame. We now present the remaining sequence of the dengue type 4 virus genome which codes for the nonstructural proteins. The entire genome, which is 10,644 nucleotides in length, contains one long open reading frame which codes for a single large polyprotein 3386 amino acids in length. Alignment of the dengue nonstructural protein sequence with that of other flaviviruses, including yellow fever and West Nile viruses, revealed that significant homology exists throughout the entire nonstructural region of the dengue genome and this allowed tentative assignment of individual nonstructural proteins in the following order: NS1, NS2a, NS2b, NS3, NS4a, NS4b, and NS5-COOH. Processing of the nonstructural proteins appears to involve two types of proteolytic cleavage: the first occurs after a long hydrophobic signal sequence and the second occurs at a junction between two basic amino acids and a small polar amino acid. A notable exception is the cleavage at the N-terminus of the dengue NS3 which may take place at the junction between Gln-Arg and Ser. Comparative analysis suggests that dengue NS3 and NS5 may be involved in enzymatic activities related to viral replication and/or transcription. Putative nonstructural proteins NS2a, NS2b, NS4a, and NS4b are extremely hydrophobic, suggesting that these proteins are most likely associated with cellular membranes.