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Winterberry (Ilex verticillata (L.) A. Gray) is a recently introducedornamental tree species in China that has not been closely investigated for its drought resistance. In this study, we used two-year-old cuttings from I. verticillata (L.) A. Gray and two representative varieties derived from it, I. verticillata 'Oosterwijk' and I. verticillata 'Jim Dandy', as materials to investigate how this plant responds to drought stress and whether exogenous spermidine (SPD) can alleviate the negative effects caused by drought stress. The results showed that as the degree of drought stress increased, the leaves of winterberry seedlings became chlorotic, and their edges became dry. Similarly, the relative water content, specific leaf weight, chlorophyll content, leaf nitrogen content, net photosynthetic rate, stomatal conductance and transpiration rate were significantly reduced, whereas the content of malondialdehyde continuously increased with the degree of drought stress. The activities of superoxide dismutase, peroxidase, and catalase increased undermoderate drought stress and then decreased under severe drought stress. The levels of soluble sugar and abscisic acid continued to increase, while those of auxin and gibberellic acid decreased. When compared with individual drought stress, an increase in the amount of external SPD clearly alleviated the effect of drought stress on winterberry seedlings. The combined phenotypes and physiological indices of the winterberry leaves under drought stress conditions revealed that the drought resistance of the native species was significantly higher than its two varieties. This finding serves as an important theoretical foundation for the popularization and application of I. verticillata (L.) A. Gray and the two varieties. [ABSTRACT FROM AUTHOR]

Semi-volatile organic compounds (SVOCs), including polycyclic aromatic hydrocarbons (PAHs), phthalates and pesticides in water of Wujin river inflow into Taihu Lake, were detected for assessment of risk to human health. SVOCs were tested with Method 525.2 established by the US Environmental Protection Agency (EPA) and health risk assessment (HRA) was conducted by the hazard quotient (HQ) approach from US HRA for screening stage. The results for the liquid-solid extraction of water sample measured by gas chromatography/mass spectrometry (GC/MS) showed that three of the tested twenty-three semi-volatile organic contaminants posed potential health risk and the concentrations of 2,4-dinitrotoluene, di- n-butyl phthalate, chrysene and benzo(a)anthracene was 0.736, 15.201, 0.307, and 0.334 μg/l, respectively. SVOCs in the Wujin river water might induce risk to environmental health of Taihu Lake as a source of drinking water. [ABSTRACT FROM AUTHOR]

Basic characteristics of Ordovician carbonate reservoir beds in the Lungudong region of northeastern part of the Tarim Basin are described in detail and the reservoir-forming conditions of oil and gas are preliminarily discussed in this paper by collecting and sorting out a large amount of data. The carbonate reservoir beds are mainly developed in open-platform and platform marginal facies; the reservoir beds have large changes in and low average values of physical property; the main type is fractured reservoir beds with the fracture-porous type second. The reservoir bed development is chiefly controlled by the distribution of sedimentary facies, tectonic activity and karstification. Whereas the accumulation and distribution of hydrocarbons in the region are controlled by an advantageous structural location, a good reservoir-caprock combination and a favorable transporting system, with the distribution characterized by zones horizontally and belts vertically, the oil and gas are mainly concentrated in areas with structural uplift, densely developed fractures, and surface karst, a vertical vadose zone, and a horizontal undercurrent belt of palaeokarst. [ABSTRACT FROM AUTHOR]

In recent years, great progress has been made constantly in oil and gas exploration in the Lungudong region of the Tarim Basin. However, progress has been slow in the evaluation of its main oil-producing horizons - the Ordovician carbonate reservoir beds. Based on previous researches and on the various data such as drilling, geology and oil test, in combination with the interpretation of each single-well imaging and conventional logging data, and through analysis and comparison, the identification methods in imaging and conventional logging for four types of carbonate reservoir beds in this region are summarized in this paper. Calculation formulas for four reservoir bed parameters, i. e. shale content, porosity, permeability and oil saturation in this region are proposed; and reservoir beds in this region are divided into three levels (I, II and III) by combining oil test data and logging data, The lower limits of the effective porosity of reservoir beds and the fracture porosity of effective reservoir beds are determined as 1.8% and 0.04%, respectively. The physical property parameters are calculated by conventional logging curves, and the most advantageous areas for reservoir development are predicted comprehensively. On the plane, the high-value zones of reservoir bed parameters are mainly concentrated in the N-S-trending strike-slip fault, the Sangtamu fault horst zone and near the LG38 well area; vertically, the reservoir bed parameters of the Yijianfang Formation are better than those of the Yingshan and Lianglitage formations. [ABSTRACT FROM AUTHOR]

So far there has been no common opinion on oil source of the Chepaizi swell in the Junggar Basin. Therefore, it is difficult to determine the pathway system and trend of hydrocarbon migration, and this resulted in difficulties in study of oil-gas accumulation patterns. In this paper, study of nitrogen compounds distribution in oils from Chepaizi was carried out in order to classify source rocks of oils stored in different reservoirs in the study area. Then, migration characteristics of oils from the same source were investigated by using nitrogen compounds parameters. The results of nitrogen compounds in a group of oil/oil sand samples from the same source indicate that the oils trapped in the Chepaizi swell experienced an obvious vertical migration. With increasing migration distance, amounts and indices of carbazoles have a regular changing pattern (in a fine linear relationship). By using nitrogen compounds techniques, the analyzed oil/oil sand samples of Chepaizi can be classified into two groups. One is the samples stored in reservoir beds of the Cretaceous and Tertiary, and these oils came from mainly Jurassic source rock with a small amount of Cretaceous rock; the other is those stored in the Jurassic, Permian and Carboniferous beds, and they originated from the Permian source. In addition, a sample of oil from an upper Jurassic reservoir (Well Ka 6), which was generated from Jurassic coal source rock, has a totally different nitrogen compound distribution from those of the above-mentioned two groups of samples, which were generated from mudstone sources. Because of influence from fractionation of oil migration, amounts and ratios of nitrogen compounds with different structures and polarities change regularly with increasing migrating distance, and as a result the samples with the same source follow a good linear relationship in content and ratio, while the oil samples of different sources have obviously different nitrogen compound distribution owing to different organic matter types of their source rocks. These conclusions of oil source study are identical with those obtained by other geochemical bio-markers. Therefore, nitrogen compounds are of great significance in oil type classification and oil/source correlation. [ABSTRACT FROM AUTHOR]

Background: Human-like H3N2 influenza viruses have repeatedly been transmitted to domestic pigs in different regions of the world, but it is still uncertain whether any of these variants could become established in pig populations. The fact that different subtypes of influenza viruses have been detected in pigs makes them an ideal candidate for the genesis of a possible reassortant virus with both human and avian origins. However, the determination of whether pigs can act as a "mixing vessel" for a possible future pandemic virus is still pending an answer. This prompted us to gather the epidemiological information and investigate the genetic evolution of swine influenza viruses in Jilin, China. Methods: Nasopharyngeal swabs were collected from pigs with respiratory illness in Jilin province, China from July 2007 to October 2008. All samples were screened for influenza A viruses. Three H3N2 swine influenza virus isolates were analyzed genetically and phylogenetically. Results: Influenza surveillance of pigs in Jilin province, China revealed that H3N2 influenza viruses were regularly detected from domestic pigs during 2007 to 2008. Phylogenetic analysis revealed that two distinguishable groups of H3N2 influenza viruses were present in pigs: the wholly contemporary human-like H3N2 viruses (represented by the Moscow/10/99-like sublineage) and double-reassortant viruses containing genes from contemporary human H3N2 viruses and avian H5 viruses, both co-circulating in pig populations. Conclusions: The present study reports for the first time the coexistence of wholly human-like H3N2 viruses and double-reassortant viruses that have emerged in pigs in Jilin, China. It provides updated information on the role of pigs in interspecies transmission and genetic reassortment of influenza viruses. [ABSTRACT FROM AUTHOR]

The animal feed industry in China has become an important industry after 40 years of development and it continues to grow. This paper adopts an autocorrelation analysis to study the spatial distribution of the industry. The developmental status of the feed industry in adjacent provinces is compared and contrasted. The research shows that spatial autocorrelation is very small, suggesting that the feed industry is tending towards being more distributed and this trend is gaining in strength. Using a local spatial autocorrelation analysis, the author also summarises the character of the feed industry distribution in several bordering provinces. [ABSTRACT FROM AUTHOR]

Abstract: Tarim Basin is the largest petroleum potential in the west of China. Tazhong Areas are located in the centre of the Tarim, and have been thought to be the key region for seeking the large oil–gas fields in the Tarim. Paleozoic is presently the major oil–gas producing strata in the Tazhong Areas, and it is really important to petroleum exploration and development in the basin. Therefore, the basic characteristics of the Paleozoic reservoir beds of the Tazhong Areas were described in detail in this paper by collecting and processing plenty of existing data. Several points about reservoir bed and oil–gas accumulation, which are presently paid close attention to, were discussed based on the reservoir bed characteristics. The results showed that clastic-rock reservoir beds with high porosity and permeability are distributed in the southeastern part of the Tazhong Areas, while carbonate reservoirs with good physical properties are all along the No. 1 Fault belt. Cements (especially carbonate cement) amount is the major factor controlling physical properties of clastic rock reservoir beds, and the sedimentary environment is that controlling those of the carbonate reservoir beds. In the Tazhong Areas, the oil–gas distributions within the Carboniferous and Silurian clastic-rock reservoir beds are closely related to the physical properties; the distributions within the Ordovician carbonates have close relation to the reservoir bed type. Finally, favorable belts for petroleum exploration in the Tazhong Paleozoic strata were predicted on the basis of relationship between oil–gas distributions and reservoir bed characteristics. [Copyright &y& Elsevier]

• Consecutive crashes are primary crashes and immediately caused secondary crashes. • Traffic hazards transmit through vehicular interactions for consecutive crashes. • Two-level logistic model outperforms random-effects and random parameter models. • Factors for consecutive crashes are investigated. A consecutive crash consists of a primary crash and one or more secondary crashes that occur subsequently in a short period of time within a certain distance. It often affects a relatively large area of road space and the traffic disruption created can be difficult for traffic managers to control and resolve. This study identifies the factors delineating a primary crash that results in secondary crashes within a minute from a regular crash that does not result in any secondary crashes. Random-effects, random-parameter and two-level binary logistic regression models are applied to data collected on 8779 crashes on the freeway network of the Guizhou Province, China in 2018, of which 299 are consecutive crashes. According to the AIC values, the two-level logistic model outperforms the other two models. Rear-end primary crashes have a significant random effect varying across road segments on the occurrence of consecutive crashes. Various crash types (rear-end, roll-over and side-swipe), tunnel crash and foggy weather are positively associated with the possibility to cause subsequent consecutive crashes, whereas single-vehicle crash, truck involvement and the time periods with poorer natural lighting are less likely to incur consecutive crashes. Recommendations are provided to minimize the possibility of the occurrence of consecutive crashes on a freeway. [ABSTRACT FROM AUTHOR]