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The present study was undertaken to investigate the gender-related liver injury induced by Dioscorea bulbifera L. (DB), a traditional medicinal plant, in mice, and further explored its hepatotoxic chemical compound. Serum and liver tissue samples were collected at 0, 4, 8, 12 h, after mice were administrated orally with 640 mg/kg ethyl acetate extracts (EF) isolated from DB. After treatments, serum alanine transaminase (ALT) and aspartate transaminase (AST) activities were both significantly elevated. Liver lipid peroxidation (LPO) level increased, while glutathione amounts, glutathione-S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT) activities all decreased in the time-dependent manner. Further analysis demonstrated that ALT and AST activities in female mice were significantly lower than those in male. Meanwhile, liver glutathione amounts and CAT activity in female mice after giving EF for 12 h were both higher than those in male. Further, comparing the liver injury induced by Diosbulbin B isolated from DB with that induced by EF on the basis of chemical analysis for the amounts of Diosbulbin B in EF of DB, we found that Diosbulbin B could be the main hepatotoxic chemical compound in DB. Taken together, our results show that DB can induce gender-related liver oxidative stress injury in mice, and its main hepatotoxic chemical compound is Diosbulbin B, for the first time. [ABSTRACT FROM AUTHOR]

Gene flow data from experiments under limited environmental conditions (e.g. wind speed and direction, atmospheric stability) have only provided limited information for gene flow risk management. It is necessary to apply models to predict the gene flow under a complete set of possible environmental conditions to inform farmers, seed companies, government agencies, and researchers about the risks and potential prevention and precaution methods. In this paper, the previous validated gene flow model developed by the authors was used to predict gene flow from genetically modified (GM) corn crops. The model was used to simulate potential gene flow from GM corn sources of different sizes from one plant area of 0.1 m² to an area 3.1×106 m² under normal weather conditions. In addition, the model was also used to predict the potential gene flow for different source strengths, atmospheric conditions, buffer heights, buffer field sizes, and pollen settling speeds from 10,000 m² sources. The model simulations have provided gene flow information for risk management under the above conditions and have shown that the source sizes, source strengths, buffer heights, buffer sizes, atmospheric conditions, and pollen settling speeds had important effects on gene flow. While the atmospheric conditions and pollen settling speeds cannot be controlled, choosing appropriate buffer heights and sizes will effectively prevent gene flow. The lost seed control is crucial to limit gene flow because even a GM corn plant can result in a grand total deposition flux of 646,272 grains/m², an outcrossing ratio of 0.016, and outcrossed seed of 110 kernels/m² at 0.8 m from the plant in the non-target field under normal atmospheric conditions. [ABSTRACT FROM AUTHOR]

Pollen-mediated gene flow from genetically modified plants to non-target plants is a concern of crop growers, seed companies, the general public, and the scientific community. Although there have been descriptive and mechanistic models to describe pollen dispersion, there has rarely been a comprehensive mechanistic model to dynamically simulate pollen release, dispersion, and deposition and to finally relate them to the gene flow (outcrossing). This paper developed and validated such a comprehensive mechanistic model for corn crop gene flow risk management. Dynamic pollen dispersion and deposition were predicted by a 3-D random walk model according to inputs of weather data and plant and domain characteristics. Actual gene flow (outcrossing ratio) was obtained according to predicted grand total deposition flux at silk height during the whole pollination season. The model was validated by experimental data and was appropriate to predict gene flow with acceptable accuracy under different atmospheric and environmental conditions; on average, the ratios of measured and simulated values ranged from 0.82 to 1.21, while R2 ranged from 0.56 to 0.68. The model can be easily adapted for other genetically modified crops. [ABSTRACT FROM AUTHOR]

Background: The SWR1 complex is important for the deposition of histone variant H2A.Z into chromatin necessary to robustly regulate gene expression during growth and development. In Arabidopsis thaliana, the catalytic subunit of the SWR1-like complex, encoded by PIE1 (PHOTOPERIOD-INDEPENDENT EARLY FLOWERING1), has been shown to function in multiple developmental processes including flowering time pathways and petal number regulation. However, the function of the PIE1 orthologs in monocots remains unknown. Methodology/Findings: We report the identification of the rice (Oryza sativa) ortholog, OsPIE1. Although OsPIE1 does not exhibit a conserved exon/intron structure as Arabidopsis PIE1, its encoded protein is highly similar to PIE1, sharing 53.9% amino acid sequence identity. OsPIE1 also has a very similar expression pattern as PIE1. Furthermore, transgenic expression of OsPIE1 completely rescued both early flowering and extra petal number phenotypes of the Arabidopsis pie1-2 mutant. However, homozygous T-DNA insertional mutants of OsPIE1 in rice were embryonically lethal, in contrast to the viable mutants in the orthologous genes for yeast, Drosophila and Arabidopsis (Swr1, DOMINO and PIE1, respectively). Conclusions/Significance: Taken together, our results suggest that OsPIE1 is the rice ortholog of Arabidopsis PIE1 and plays an essential role in rice embryo development. [ABSTRACT FROM AUTHOR]

Scintillometers are becoming increasingly popular for the validation of satellite remote sensing sensible heat-flux estimates due to the comparable spatial resolutions. However, it is important to gain confidence in the accuracy of the sensible heat-flux measurements obtained by the scintillometer. Large aperture scintillometer (LAS) and eddy-covariance (EC) measurements were collected over a homogeneous, dry and semi-arid region near Las Cruces, New Mexico, USA, where the homogeneity allowed direct comparison of the two instruments despite their differences in footprint sizes. The differences between the sensible heat-flux measured by both LAS and EC systems fall within the differences between two EC systems. We conclude that the large aperture scintillometer is a reliable system for measuring sensible heat flux in a dry semiarid region. [ABSTRACT FROM AUTHOR]

Pollen-mediated gene flow from transgenic crops is a concern of the scientific community as well as the general public. Current lack is a nondestructive method to measure dynamic (hourly or shorter time period) source pollen release rate (source strength) from these crops. This paper reports an improved method using Rotorod concentration samplers and sticky slides, together with a fast response sonic anemometer, for measuring source strength from transgenic corn crops. Field measurements were made during the pollination season of 2001 at the Agronomy Research Farm, University of Connecticut, Storrs, Connecticut. Data were analyzed and used to estimate the pollen source strength of the corn crops at hourly time steps by considering both atmospheric transport and gravitational deposition processes. Details of the calculation and assumptions of the method are provided. Results from this study demonstrate that this method is sufficiently robust for use in estimating pollen source strength of transgenic crops with heavy pollen grains in assessing gene flow risks associated with field production of transgenic crops. [ABSTRACT FROM AUTHOR]

This article discusses the concentrations of particulate matter in dust plumes emitted during harvesting and tilling in an irrigated cotton field near Las Cruces, New Mexico. The authors compared remote lidar measurements with air samplers. They found strong agreement between the two techniques for concentrations of particulate matter and total suspended particulates. Plume movement was impacted by atmospheric stability and wind field. They concluded that there is a potential exposure risk to people in and around farming operations based on the measured concentrations of particulate matter.

Increased flash drought awareness in recent years has motivated the development of numerous indicators for monitoring, early warning, and assessment. The flash drought indicators can act as a complementary set of tools by which to inform flash drought response and management. However, the limitations of each indicator much be measured and communicated between research and practitioners to ensure effectiveness. The limitations of any flash drought indicator are better understood and overcome through assessment of indicator sensitivity and consistency; however, such assessment cannot assume any single indicator properly represents the flash drought "truth." To better understand the current state of flash drought monitoring, this study presents an intercomparison of nine, widely used flash drought indicators. The indicators represent perspectives and processes that are known to drive flash drought, including evapotranspiration and evaporative demand, precipitation, and soil moisture. We find no single flash drought indicator consistently outperforms all others across the contiguous United States. We do find the evaporative demand- and evapotranspiration-driven indicators tend to lead precipitation- and soil moisture-based indicators in flash drought onset, but also tend to produce more flash drought events collectively. Overall, the regional and definition-specific variability in results supports the argument for a multi-indicator approach for flash drought monitoring, as advocated by recent studies. Furthermore, flash drought research-especially evaluation of historical and potential future changes in flash drought characteristics-should test multiple indicators, datasets, and methods for representing flash drought, and ideally employ a multi-indicator analysis framework over use of a single indicator from which to infer all flash drought information. SIGNIFICANCE STATEMENT: Rapid onset or "flash" drought has been an increasing concern globally, with quickly intensifying impacts to agriculture, ecosystems, and water resources. Many tools and indicators have been developed to monitor and provide early warning for flash drought, ideally resulting in more time for effective mitigation and reduced impacts. However, there remains no widely accepted single method for defining, monitoring, and measuring flash drought, which means most indicators that are developed are compared with other individual indicators or conditions and impacts in one or two flash drought events. In this study, we measure the state of flash drought monitoring through an intercomparison of nine, widely used flash drought indicators that represent different aspects of flash drought. We find that no single flash drought indicator outperformed all others and suggest that a comprehensive flash drought monitor should leverage multiple, complementary indicators, datasets, and methods. Furthermore, we suggest flash drought research-especially that which reflects on historical or projected changes in flash drought characteristics-should seek multiple indicators, datasets, and methods for analyses, thereby reducing the potentially confounding effects of sensitivity to a single indicator. [ABSTRACT FROM AUTHOR]

As a common approach to nondestructive testing and evaluation, guided wave-based methods have attracted much attention because of their wide detection range and high detection efficiency. It is highly desirable to develop a portable guided wave testing system with high actuating energy and variable frequency. In this paper, a novel giant magnetostrictive actuator with high actuation power is designed and implemented, based on the giant magnetostrictive (GMS) effect. The novel GMS actuator design involves a conical energy-focusing head that can focus the amplified mechanical energy generated by the GMS actuator. This design enables the generation of stress waves with high energy, and the focusing of the generated stress waves on the test object. The guided wave generation system enables two kinds of output modes: the coded pulse signal and the sweep signal. The functionality and the advantages of the developed system are validated through laboratory testing in the quality assessment of rock bolt-reinforced structures. In addition, the developed GMS actuator and the supporting system are successfully implemented and applied in field tests. The device can also be used in other nondestructive testing and evaluation applications that require high-power stress wave generation. [ABSTRACT FROM AUTHOR]

This paper discusses the construction method of ventilation and prevention system based on the application practice of Zhuanlongwan Coal Mine. A precise perception technology for key parameters of ventilation network is proposed. Through the optimal arrangement of sensors and the use of the least monitoring points, the correlation parameter analysis of the whole mine ventilation resistance route is achieved; the remote software modules of the main ventilator, local ventilator, and ventilation facilities are developed by extracting the ventilation and prevention information of the safety monitoring system, and the modules such as beam pipe monitoring, dust monitoring, grouting monitoring, and personnel positioning system are integrated; the intelligent analysis technology for the state of the ventilation and prevention system is proposed, and the three-dimensional simulation model of the mine ventilation network is established, which achieves the real-time calculation of the ventilation network, the visual display and trend analysis of the ventilation and prevention parameters, and the diagnosis and early warning of ventilation anomalies. By organically integrating ventilation, gas, fire, dust and other ventilation and prevention safety information, a hierarchical management and control mode of mine ventilation and prevention system based on multi heterogeneous information integration is proposed, a mine intelligent ventilation and prevention platform is developed, and mine emergency management and control platform is invented. Through field practice, the relevant parameter judgment and control model are verified, which provides application experience for the construction of mine intelligent ventilation and prevention system.

Extensive efforts have been made to determine the status on neural progenitor cell proliferation in specific pathological conditions and to evaluate the therapeutic efficacy of drugs for preventing neurogenic deficits in neurodegenerative diseases. However, the most commonly used stereological analysis using 5-bromo-2'-deoxyuridine (BrdU) immuno-positive sections is a time consuming and labor intensive process and is often a bottle neck in neurogenic drug development, particularly when large sample sizes are needed. In addition, BrdU is toxic to new born neurons and also labels DNA damage in old cells. In this study, we established a method that quantitatively measures the number of Ki-67, an endogenous cell proliferation marker, positive cells by flow cytometry which analyzes extracted cell nuclei from rodent hippocampi in suspension. Our results demonstrate that this approach can be applied to a large number of rodent samples, can be accomplished in a short period of time (1-3 days), and can be completed in a more accurately objective manner than by using 3-D cell counting with immunohistochemically processed sections. [ABSTRACT FROM AUTHOR]

• Good determination of 20 antihistamines was obtain at 8 min by UHPLC. • Dispersive micro solid phase extraction is efficient for extracting antihistamines. • Compared with existing methods, this method showed lower LODs. • Results of antihistamines in milk shown maybe be noteworthy issues for human. Ultrahigh-performance liquid chromatography coupled with high-field quadrupole Orbitrap high resolution mass spectrometry was used for the separation and determination of 20 antihistamines, and a dispersive micro solid-phase extraction procedure using high-performance absorbing material was developed as a sample preparation strategy for extracting 20 antihistamines from milk. Instrument conditions and key parameters influencing extraction efficiency were investigated to obtain an optimized method. The limit of detection for 20 antihistamines in milk using this method is 0.05 µg/L to 1.0 µg/L. Recoveries are between 80.7 % and 108.3 %, and the relative standard deviation is less than 15 %. It is suitable for confirmatory monitoring and quantitative analysis of 20 antihistamines in milk. The results show that antihistamines in milk may be noteworthy issues for human health and environmental pollution. [ABSTRACT FROM AUTHOR]