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American sloughgrass (Beckmannia syzigachne Steud.) is a problematic grass that is widely distributed in wheat and oilseed rape fields in China. The herbicides fenoxaprop-P-ethyl and mesosulfuron-methyl failed to control B. syzigachne JCWJ-R populations collected from a wheat field in Jiangsu Province. Dose-response experiments showed that JCWJ-R was resistant to the acetyl-CoA carboxylase (ACCase) inhibitors fenoxaprop-P-ethyl (33.8-fold), haloxyfop-R-methyl (12.7-fold), clethodim (7.8-fold) and pinoxaden (11.6-fold), and to the acetolactate synthase (ALS) inhibitors mesosulfuron-methyl (15.9-fold), pyroxsulam (17.6-fold), flucarbazone-Na (10.7-fold) and imazethapyr (7-fold). Resistance to ALS inhibitors was due to a Pro-197-Ser mutation in the ALS gene and resistance to ACCase inhibitors was due to an Ile-1781-Leu mutation in the ACCase gene. A derived cleaved amplified polymorphic sequence method was developed to detect the ALS mutation in B. syzigachne. This was combined with a previously established method to detect Ile-1781-Leu, and the mutation frequency and homozygous mutation rates in the JCWJ-R population were determined. The evolution of multiple resistance to ACCase and ALS inhibitors in this B. syzigachne population indicated that alternative methods should be developed to control resistant weeds. [ABSTRACT FROM AUTHOR]

Non-target site resistance (NTSR) to herbicides is an increasing concern for weed control. Metabolic herbicide resistance is an important mechanism for NTSR. However, little is known about metabolic resistance at the genetic level. In this study, we have identified three fenoxaprop-P-ethyl-resistant American sloughgrass (Beckmannia syzigachne Steud.) populations, in which the molecular basis for NTSR remains unclear. To reveal the mechanisms of metabolic resistance, the genes likely to be involved in herbicide metabolism (e.g. for cytochrome P450s, esterases, hydrolases, oxidases, peroxidases, glutathione S-transferases, glycosyltransferases, and transporter proteins) were isolated using transcriptome sequencing, in combination with RT-PCR (reverse transcription-PCR) and RACE (rapid amplification of cDNA ends). Consequently, we established a herbicide-metabolizing enzyme library containing at least 332 genes, and each of these genes was cloned and the sequence and the expression level compared between the fenoxaprop-P-ethyl-resistant and susceptible populations. Fifteen metabolic enzyme genes were found to be possibly involved in fenoxaprop-P-ethyl resistance. In addition, we found five metabolizing enzyme genes that have a different gene sequence in plants of susceptible versus resistant B. syzigachne populations. These genes may be major candidates for herbicide metabolic resistance. This established metabolic enzyme library represents an important step forward towards a better understanding of herbicide metabolism and metabolic resistance in this and possibly other closely related weed species. This new information may help to understand weed metabolic resistance and to develop novel strategies of weed management. [ABSTRACT FROM AUTHOR]

Background: Androgen deprivation therapy is the primary strategy for the treatment of advanced prostate cancer; however, after an initial regression, most patients will inevitably develop a fatal androgen-independent tumor. Therefore, understanding the mechanisms of the transition to androgen independence prostate cancer is critical to identify new ways to treat older patients who are ineligible for conventional chemotherapy. Methods: The effects of 5-Aza-2'-deoxycytidine (5-Aza-CdR) on the viability and the apoptosis of the androgendependent (LNCaP) and androgen-independent (PC3) cell lines were examined by MTS assay and western blot analysis for the activation of caspase-3. The subcutaneous LNCaP xenografts were established in a nude mice model. MiR-146a and DNMTs expressions were analyzed by qRT-PCR and DNA methylation rates of LINE-1 were measured by COBRA-IRS to determine the global DNA methylation levels. The methylation levels of miR-146a promoter region in the different groups were quantified by the bisulfite sequencing PCR (BSP) assay. Results: We validated that 5-Aza-CdR induced cell death and increased miR-146a expression in both LNCaP and PC3 cells. Notably, the expression of miR-146a in LNCaP cells was much higher than in PC3 cells. MiR-146a inhibitor was shown to suppress apoptosis in 5-Aza-CdR-treated cells. In a castrate mouse LNCaP xenograft model, 5-Aza-CdR significantly suppressed the tumors growth and also inhibited prostate cancer progression. Meanwhile, miR-146a expression was significantly enhanced in the tumor xenografts of 5-Aza-CdR-treated mice and the androgen-dependent but not the androgen-independent stage of castrated mice. In particular, the expression of miR-146a was significantly augmented in both stages of the combined treatment (castration and 5-Aza-CdR). Additionally, the methylation percentage of the two CpG sites (-444 bp and -433 bp), which were around the NF-κB binding site at miR-146a promoter, showed the lowest methylation levels among all CpG sites in the combined treatment tumors of both stages. Conclusion: Up-regulating miR-146a expression via the hypomethylation of the miR-146a promoter by 5-Aza-CdR was correlated with delayed progression of castration-resistant prostate cancers. Moreover, site-specific DNA methylation may play an important role in miR-146a expression in androgen-dependent prostate cancer progression to androgenindependent prostate cancer and therefore provides a potentially useful biomarker for assessing drug efficacy in prostate cancer. [ABSTRACT FROM AUTHOR]

Background Androgen deprivation therapy is the primary strategy for the treatment of advanced prostate cancer; however, after an initial regression, most patients will inevitably develop a fatal androgen-independent tumor. Therefore, understanding the mechanisms of the transition to androgen independence prostate cancer is critical to identifying new ways to treat older patients who are ineligible for conventional chemotherapy. Methods The effects of 5-Aza-2'-deoxycytidine (5-Aza-CdR) on the viability and the apoptosis of the androgen-dependent (LNCaP) and androgen-independent (PC3) cell lines were examined by MTS assay and western blot analysis for the activation of caspase-3. The subcutaneous LNCaP xenografts were established in a nude mice model. MiR-146a and DNMTs expressions were analyzed by qRT-PCR and DNA methylation rates of LINE-1 were measured by COBRA-IRS to determine the global DNA methylation levels. The methylation levels of miR-146a promoter region in the different groups were quantified by the bisulfite sequencing PCR (BSP) assay. Results We validated that 5-Aza-CdR can induce cell death and increased miR-146a expression in both LNCaP and PC3 cells. Notably, the expression of miR-146a in LNCaP cells was much higher than in PC3 cells. MiR-146a inhibitor was shown to suppress apoptosis in 5-Aza-CdR-treated cells. In a castrate mouse LNCaP xenograft model, 5-Aza-CdR significantly suppressed the tumors growth and also inhibited prostate cancer progression. Meanwhile, miR-146a expression was significantly enhanced in the tumor xenografts of 5-Aza-CdR-treated mice and the androgen-dependent but not the androgen-independent stage of castrated mice. In particular, the expression of miR-146a was significantly augmented in both stages of the combined treatment (castration and 5-Aza-CdR). Additionally, the methylation percentage of the two CpG sites (-444 bp and -433 bp), which were around the NF-κB binding site at miR-146a promoter, showed the lowest methylation levels among all CpG sites in the combined treatment tumors of both stages. Conclusion Up-regulating miR-146a expression via the hypomethylation of the miR-146a promoter by 5-Aza-CdR was correlated with delayed progression of castration-resistant prostate cancers. Moreover, site-specific DNA methylation may play an important role in miR-146a expression in androgen-dependent prostate cancer progression to androgen-independent prostate cancer and therefore provide a potentially useful biomarker for assessing drug efficacy in prostate cancer. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of accurate path following control for an underactuated unmanned underwater vehicle (UUV) in the horizontal plane. For an underactuatedUUV, the line-of-sight (LOS) guidance method is adopted tomap 2Dreference trajectory into a desired orientation, and through the tracking of heading to achieve path following, where the sideslip is introduced to modify the desired orientation. In this paper, we propose a method called dynamic surface and active disturbance rejection control (DSADRC) to solve the path following control problem. This controller can effectively avoid the phenomenon of explosion of terms in the conventional backstepping method, reduce the dependence on the UUV controller mathematical model, and enhance the antijamming ability. Simulation is carried out to verify the effectiveness of the proposed control method for an underactuated UUV. The results show that, even for this controller with disturbance, the cross-track error of UUV is gradually converged to zero and has some certain robustness. [ABSTRACT FROM AUTHOR]

The formation of ordered complex structures is one of the most challenging fields in the research of biomimic materials because those structures are promising with respect to improving the physical and mechanical properties of man-made materials. In this letter, we have developed a novel approach to fabricating complex structures on the mesoscale by combining magnetic-field-induced locomotion and supramolecular-interaction-assisted immobilization. We have employed a magnetic field to locomote the glass fiber, which was modified by the layer-by-layer self-assembly of magnetic nanoparticles, to desired positions and have exploited the supramolecular interaction to immobilize glass fiber onto the appointed position. By magnetically induced micromanipulation, we can drive another fiber across the former one and finally obtain a crossing structure, which can lead to more complex structures on the mesocale. Moreover, we have constructed a mesoscale structure, termed “CHEM”, to demonstrate further the application of this method. [ABSTRACT FROM AUTHOR]

The Qinghai-Tibet Plateau is an important ecological security barrier in China. Considering the rich local waste biomass with a single treatment method and low level of resource utilization, biochar utilization of solid waste biomass can be carried out based on the research that biochar has abundant material sources. According to the application methods of various types of solid waste resources that have not been carried out, this review analyzes and discusses various types of waste biomass resources in the plateau region, such as sewage plant sludge, food waste, green leaves, barley straw, yak manure, and the unique Tibetan tea and Tibetan medicine residue waste, and reviews the biochar methods and applications for similar raw materials at home and abroad. Further, the technical outlook of solar pyrolysis technology and UV radiation modification technology and the development of hybrid pyrolysis to enhance the performance of biochar materials and heavy metal passivation are proposed by utilizing the solar energy resources of the Tibetan Plateau. Collectively, it provides a reference for prevention and restoration methods for the fragile ecological environment of the Qinghai-Tibet Plateau, reduces the pressure of waste disposal in the region, and realizes the resource utilization of waste. [ABSTRACT FROM AUTHOR]

Micro-nano BaM hollow multiphase ceramic microspheres (HMCMs) and Mg-doped and Sr-doped BaM HMCMs were prepared by combining the low-temperature self-reactive quenching method with heat treatment. The effects of Mg or Sr doping on the intrinsic characteristics and absorption properties of micro-nano BaM HMCMs were investigated. The results showed that Mg or Sr doping modified the phase compositions and particle size distributions of the HMCMs. The Mg- and Sr-doped BaM HMCMs had large real and imaginary permittivities and large real permeabilities at low frequencies relative to the, undoped HMCM. To maximize the absorption properties of the undoped and Sr- and Mg-doped HMCMs, optimal thicknesses of 8, 10 and 10 mm were used with corresponding reflectivities of −8.2, −31.5 and −26.6 dB, respectively. [ABSTRACT FROM AUTHOR]

Flexible silica aerogel composites in intact monolith of 12 cm were successfully fabricated by reinforcing SiO2 aerogel with electrospun polyvinylidene fluoride (PVDF) webs via electrospinning and sol-gel processing. Three electrospun PVDF webs with different microstructures (e.g., nanofibers, microparticles, and combined nanofibers and microparticles) were fabricated by regulating electrospinning parameters. The as-electrospun PVDF webs with various microstructures were impregnated into the silica sol to synthesize the PVDF/SiO2 composites followed by solvent exchange, surface modification, and drying at ambient atmosphere. The morphologies of the PVDF/SiO2 aerogel composites were characterized and the thermal and mechanical properties were measured. The effects of electrospun PVDF on the thermal and mechanical properties of the aerogel composites were evaluated. The aerogel composites reinforced with electrospun PVDF nanofibers showed intact monolith, improved strength, and perfect flexibility and hydrophobicity. Moreover, the aerogel composites reinforced with the electrospun PVDF nanofibers had the lowest thermal conductivity (0.028W·m-1 ·K-1). It indicates that the electrospun PVDF nanofibers could greatly improve the mechanical strength and flexibility of the SiO2 aerogels while maintaining a lower thermal conductivity, which provides increasing potential for thermal insulation applications. [ABSTRACT FROM AUTHOR]

V2O5nanofibers and three vanadium-based oxides with different structures (MnV2O6nanosheets, FeVO4·0.92H2O nanoneedles, and Sn2VO6·0.78H2O nanoparticles) were synthesized via a hydrothermal method. Field-emission scanning electron microscopy, transmission electron microscopy, electron diffraction, energy dispersive X-ray, and electron energy loss spectroscopy were employed to characterize their morphologies and crystal structures. Electrochemical tests in rechargeable lithium batteries show that among these vanadium-based oxides Sn2VO6·0.78H2O nanoparticles exhibit the highest capacity, more than 1700 mAh g−1, and can keep good capacity retention. The magnetic properties of MnV2O6nanosheets and FeVO4·0.92H2O nanoneedles were also investigated. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this 13-study (seven double-blind/placebo-controlled, six open-label) meta-analysis is to determine the effectiveness and tolerability of long-term atomoxetine treatment among young children with attention-deficit/hyperactivity disorder (ADHD).Method: Data were pooled from 6- and 7-year-olds (N = 272) who met DSM-IV criteria for ADHD, received atomoxetine treatment, and were enrolled in clinical trials of > or =2 years. Of these, 97 subjects reached the 24-month time point, providing data for long-term trend analysis of safety and effectiveness.Results: Effectiveness for most subjects was maintained over long-term treatment, as demonstrated by total scores and total T scores on the Attention-Deficit/Hyperactivity Disorder Rating Scale-IV-Parent Version, investigator administered and scored. During the 2-year period, 25.7% discontinued because of lack of effectiveness, but adverse events were clinically minor and transient, and only 4.0% of children discontinued because of an adverse event. Notable effects on growth were seen during early phases of the study, with attenuation occurring by the 2-year time point. Statistically significant increases in pulse and blood pressure and decreases in cardiac PR interval were seen, but no changes were deemed both statistically significant and clinically meaningful among any vital signs, electrocardiographic measures, or laboratory tests.Conclusion: Long-term atomoxetine treatment appears generally well tolerated and effective in the treatment of young children with ADHD. [ABSTRACT FROM AUTHOR]