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Shrub encroachment onto grassland is a global problem, and thus the relationship between shrub encroachment and grazing disturbance needs to be clarified. In this study, we set up two treatments in China's desert steppe, including no grazing (CK) and heavy grazing (HG). We aimed to analyze the impact of grazing on carbon storage in shrublands and herbaceous communities. We utilized Real-Time Kinematic Positioning (RTK) and ground-penetrating radar (GPR) to detect and quantify aboveground / belowground biomass of Caragana microphylla. We also measured the biomass of grass. The resulting model for the aboveground biomass of C. microphylla was y = 22.45e4.5562x, where x denotes the canopy area (R² = 0.96). The resulting model for the root biomass of C. microphylla was y = 3×10-5x - 23.618 (R² = 0.99), where x is amplitude. The coarse root / shoot ratios of the shrub were 8.06 and 8.92 in the CK and HG treatments, respectively. Heavy grazing significantly reduced the density and biomass of both C.microphylla and the broader community (shrub + grass) (P<0.05). The carbon stock of vegetation was significantly greater in shrubby grassland than in Stipa breviflora grassland (P<0.05). Our results show that shrub encroachment increased carbon storage and plant diversity in the desert steppe, while, at the same time, heavy grazing affect the shrub encroachment by C. microphylla. [ABSTRACT FROM AUTHOR]

The mechanical and thermodynamic properties of intermetallic compounds in the Ni-Ti system are studied by first-principles calculations. All phases show anisotropic elasticity in different crystallographic directions, in which Ni3Ti and NiTi2 are approaching the isotropy structure. The elastic moduli and Vicker's hardness of Ni-Ti system intermetallic compounds decrease in the following order: Ni3Ti B2_NiTi B19_NiTi NiTi2, and Ni3Ti shows the best mechanical properties. The intrinsic ductile nature of Ni-Ti compounds is confirmed by the obtained / ratio. The temperature dependence of linear thermal expansion coefficients (LTECs) of the compounds is estimated by the quasi-harmonic approximation (QHA) method. Ni3Ti shows the largest values among all Ni-Ti intermetallic compounds. At room temperature, the LTEC for Ni3Ti is 8.92 × 10 K, which falls in between the LTEC of zirconia toughened alumina (ZTA) (7.0-9.5 × 106 K) and iron matrix (9.2-16.9 × 106 K); i.e., the thermal matching of the ZTA/iron composite will be improved by introducing Ni3Ti intermetallic compound into their interface. Other thermodynamic properties such as sound velocity and Debye temperature are also obtained. [ABSTRACT FROM AUTHOR]

The Tinjar-West Baram Line is a NW-trending trans-lithospheric fault in northern Kalimantan; its northwestern extension into the South China Sea (SCS) is the West Baram Line. In this paper, we propose that the geodynamic processes of the proto-South China Sea (PSCS) played a key role in the formation and evolution of the Tinjar-West Baram Line, based on previous studies of the strata, crustal thicknesses, gravity anomalies and other characteristics of the blocks adjacent to the Tinjar-West Baram Line and the palaeomagnetic-based plate reconstructions of the PSCS. The Tinjar-West Baram Line has a close link to the subduction of the PSCS. Structural restoration reveals that (1) before 35 Ma, the Tinjar-West Baram Line was a NE-trending transform fault, which is consistent with the NE-trending strike-slip faults widely distributed in the East Asian Continental Margin, in the PSCS. (2) From the perspective of tectonic evolution, the extinction of the PSCS and the spreading of the SCS drove the Luconia Block in the northern SCS to accrete to the western side of the Tinjar-West Baram Line. This process resulted in a contrast of crustal rocks adjacent to the Tinjar-West Baram Line; to the east of this line, the Nansha Trough is oceanic crust, whereas to the west of this line the Luconia Block has an affinity with continental crust. The velocity and thickness of the crust show great differences on either side of the Tinjar-West Baram Line. (3) The kinematic analysis of the Tinjar-West Baram Line reveals that the collisional orogeny between the Luconia and Kalimantan blocks happened at 45-37 Ma on the west of the Tinjar-West Baram Line; on its eastern side, the Nansha Trough was subducting south towards Kalimantan Island. During the interval 35-10 Ma, the kinematics of the Tinjar-West Baram Line shows a feature of dextral strike-slip faulting. (4) The earlier published palaeomagnetic data show that the Kalimantan Block experienced a counterclockwise rotation of about 50° during the period from 25 to 10 Ma. In addition, the exert counterclockwise rotation of about 20° of the Tinjar-West Baram Line happened due to the resistance of the Luconia Block. Therefore, the Tinjar-West Baram Line changed from an early NE-trending to late NW-trending structure which results in its present day tectonic framework. Thus, we suggest that the Tinjar-West Baram Line was originally a NE-trending transform fault of the PSCS extending to the continental crust. Subsequently, the Tinjar-West Baram Line became the western border of the PSCS, accompanying the collisional orogeny between the Luconia and Kalimantan blocks. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Transform faults in back-arc basins are the key to revealing the evolution of marginal seas. Four marginal basins in the Western Pacific, i.e. the South China Sea (SCS), Okinawa Trough (OT), West Philippine Basin (WPB) and Shikoku-Parece Vela Basin (SPVB), were studied to redefine the strikes and spatial distribution of transform faults or fracture zones. Based on high-resolution tectonomorphology, gravity and magnetic anomalies, pattern of magnetic lineations, seismic profiles, geometry of basins and palaeomagnetic data, together with analyses of regional geological setting, plate reconstruction and geodynamic analysis, this paper suggests that all the transform faults in the four marginal basins are in general NNE-trending. Moreover, by comparing with the contemporary structural framework of the East Asian Continental Margin, we propose new models concerning marginal seas spreading and have revised the previous Cenozoic plate reconstruction models related to the East Asian Continental Margin and the Western Pacific marginal seas. There are three possible origins of these NNE-trending transform faults. 1. Inheriting the orientation of the strike-slip faults at the rifting continental margin (e.g. the SCS and OT). The real strike of transform faults should not be NW but NNE. The large-scale NNE-trending dextral strike-slip faults distributed in the continental shelf of the SCS control a series of pull-apart basins of the SCS. Due to a higher degree of pull-apart, oceanic crust began to open. Then they evolved into the NNE-trending transform faults in the SCS and could also be regarded as a natural extension of the NNE-trending strike-slip faults in the South China Block (SCB). The geodynamic mechanism of the OT is similar to that of the SCS. Consequently, transform faults of the OT should also be NNE-trending, which is not perpendicular to the spreading axis but instead displays oblique spreading. 2. Izu-Bonin-Mariana (IBM) Trench retreat to the NNE and NE. Subduction rollback to the NE and NNE produced the NE- and NNE-striking horizontal tensile stress, resulting in the rifting of the Kyushu-Palau Ridge (KPR), controlling the spreading of the SPVB and forming the NE- and NNE-trending transform faults. This also involves oblique spreading. 3. The later overall rotation of the Philippine Sea Plate (PSP). Since 25 Ma, the WPB has rotated clockwise about 40°. Therefore the NW- and NNW-trending transform faults that formed at the later spreading stage have rotated to be the near-N-S- or NNE-striking faults. These transform faults are almost perpendicular to the spreading axis. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The East China Sea Shelf Basin (ECSSB), the Pearl River Mouth Basin (PRMB) and the Taixinan Basin (TXNB) in the northern continental margin of the South China Sea (SCS) are important oil- and gas-bearing basins on the Western Pacific Continental Margin. During the Paleocene to Late Miocene, their strata can be compared, and the lithofacies were continuous from the TXNB, via the Taixi Basin (TXB) to the ECSSB. The lithologies mainly consist of interbedded shale, sandstone and mudstone layers. In addition, these basins have similar tectonic and sedimentation features. The three basins had similar marine-terrigenous facies in the Paleocene and marine-lacustrine-fluvial facies during the Eocene and Late Miocene. The basins experienced several coeval tectonic movements and episodes, and they developed a series of NE- and NNE-trending faults during the Paleocene and Eocene, which controlled the structure of the basins. During the Early Oligocene and Middle Miocene, they developed a series of NW- and WNW-trending strike-slip faults, reverse folds and flower-like strike-slip faults. However, there were obvious differences in sedimentary and tectonic evolution since the Late Miocene. The TXNB and TXB developed marine facies after the Late Miocene, while in the Quaternary, open marine facies replaced the Pliocene terrigenous facies in the ECSSB. Since the Late Miocene, the south of the ECSSB developed into a subsidence stage, and fault activity stopped. The TXB and TXNB developed some inverse structures and then developed into a thermal subsidence episode after the Dongsha Movement. Thus, this paper proposes that the ECSSB and the Cenozoic basins in the SCS were originally a unified basin and then subsequently separated into two basins as a result of the indentation of the Philippine Sea Plate (PSP) and the arc-continent collision between the Luzon Arc and the Eurasian Plate. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

It is well known that the ability of the immature rodent fetal beta cell to release insulin in response to a glucose challenge can be enhanced by chronic exposure to a high concentration of glucose in vitro. It might be thought that the human fetal beta cell would mature similarly in vitro, because neonates born of diabetic mothers release insulin in a more mature manner than normal infants. Using an organ culture of human fetal pancreatic explants, we have examined this possibility by exposing the tissue to 0-30 mM glucose. Six weeks of exposure of pancreatic explants to as high a concentration of glucose as 30 mM did not cause significant enhancement of the insulinogenic response to an acute challenge with 20 mM glucose. In contrast, chronic insulin release was enhanced, although culture medium containing 2.8 mM glucose was equally as efficacious as that with 30 mM glucose. Just as with insulin, proinsulin levels in the culture media containing no glucose also were suppressed. Degranulation of the beta cell exposed to high concentrations of glucose did not occur, the insulin content of the explants at the end of culture being enhanced in those maintained in 5.6-30 mM but not 2.8 mM glucose. Desensitization to the acute stimulatory effect of 10 mM theophylline did not eventuate, even in explants exposed to 30 mM glucose. In contrast to the human explants, rat fetal pancreatic explants did mature when exposed to 11.2 mM glucose for 1 week.(ABSTRACT TRUNCATED AT 250 WORDS)

In order to study the relationship between daily consumption of mouldy food and the incidence of oesophageal cancer, we examined the mutagenicity of Alternaria alternata and Penicillium cyclopium, which seriously contaminate grain in Linxian county, China. We first examined extracts of cultured strains of A. alternata. In the reverse mutation test, positive results were obtained in 85% of strains; positive results were seen in 84% of 19/20 strains in the rec assay. Eight of ten strains induced sister chromatid exchange, and two of eight strains induced chromatid breaks. Six of seven strains induced unscheduled DNA synthesis and DNA synthesis inhibition. One extract induced a higher frequency of sister chromatid exchange in lymphocytes from normal persons than in those from patients with oesophageal cancer, and the spontaneous break-points in patients were related to fragile sites and neoplasia-associated break-points. The toxins alternariol and its monomethyl ether, produced by A. alternata, were examined in the reverse mutation assay and for unscheduled DNA synthesis. The results were similar to those obtained with extracts of the different strains. Alternariol had a four to eight times greater effect than its monomethyl ether. Of 24 strains of P. cyclopium isolated from cereals in Linxian, four were cultured with rice and 19 in Raulin-Thom medium. Cultures in Raulin-Thorn medium, solution and hyphae were then extracted. The strains cultured with rice induced sister chromatid exchange, unscheduled DNA synthesis and DNA synthesis inhibition. The solution extracts of 14 strains were positive in the rec assay, and five strains were positive in the reverse mutation test.(ABSTRACT TRUNCATED AT 250 WORDS)

Blue-cotton (-rayon) adsorbable fractions of human urines were examined for mutagenicity in Salmonella typhimurium TA98 with metabolic activation. Ingestion of cooked beef caused significant increases in urinary mutagenicity that were comparable to that caused by cigarette smoking. When a sample obtained after ingestion of cooked beef was passed through a carboxymethyl cellulose column, the mutagenicity of the eluate was found to be almost one order of magnitude greater than that of the original sample, suggesting the presence of antimutagenic factors in the sample. The oleic acid content of the sample was not great enough to account for this phenomenon. Other urine samples subjected to column fractionation were found to contain the putative antimutagenic factors. This finding further confounds the monitoring of urinary mutagenicity.

A health survey was conducted among spraymen exposed to 2.5% deltamethrin EC in the cotton fields. The subjects were exposed to deltamethrin at concentrations of 0.022-24.070 micrograms/m3 in respiratory zone air and of 0.013-0.347 micrograms/cm2 of skin contact. Results showed that one-half of the 44 subjects examined complained of itching and burning sensations on their faces. A few miliary red papules also appeared on the face of one subject but not sign of acute deltamethrin poisoning was evident on physical examination. There were no significant differences between the subjects examined and the controls in sodium, potassium, and urea contents in the serum, sodium potassium ATPase and serotonin in whole blood, and 3-methyl-4-hydroxymandelic acid and 5-hydroxyindoleacetic acid in the urine. Deltamethrin in the urine of spraymen was below the detection limit (0.20 microgram/liter) of the method used.