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关键词： Lateral line anomalies   Shape analysis   Thin-plate spline   Scales disorientation   Skeletal anomalies   Heritability  

摘要： Different kinds of defects are observed on farmed fish, and while a lot of research has concentrated on skeletal abnormalities, little is known on scale anomalies. We carried out a survey for lateral line shape anomalies and disorientated scale patterns on a batch composed of crosses of 5 different wild populations of European seabass, in order to find out whether there is a genetic basis to these anomalies. Lateral line shape was standardized coupling geometric morphometrics with advanced warping procedures based on thin-plate splines. Genetic variation between and within populations was found for lateral line shape, which was also affected by vertebral anomalies to a certain extent. Conversely, no significant genetic variation was found for scale disorientation, either between or within populations. We conclude that the shape of lateral line is probably not a decisive factor to externally evaluate spine anomalies;further, its variation is more likely linked to a general variation of fish shape than to impaired early development, while the cause of scale disorientations is more environmental than genetic. (C) 2015 Elsevier B.V. All rights reserved.

摘要： Distribution and mean value of a sample correlation coefficient were found. Theoretical results are compared to computer simulation results. The simulation results are consistent with the theoretical predictions. © 2015, Springer Science+Business Media New York.

关键词： mitochondria   thiamin pyrophosphate   chronic alcohol exposure   pancreatic acinar cells   uptake  

摘要： Thiamin is essential for normal metabolic activity of all mammalian cells, including those of the pancreas. Cells obtain thiamin from their surroundings and enzymatically convert it into thiamin pyrophosphate (TPP) in the cytoplasm;TPP is then taken up by mitochondria via a specific carrier the mitochondrial TPP transporter (MTPPT;product of the SLC25A19 gene). Chronic alcohol exposure negatively impacts the health of pancreatic acinar cells (PAC), but its effect on physiological/molecular parameters of MTPPT is not known. We addressed this issue using mouse pancreatic acinar tumor cell line 266-6 and primary PAC of wild-type and transgenic mice carrying the SLC25A19 promoter that were fed alcohol chronically. Chronic alcohol exposure of 266-6 cells (but not to its nonoxidative metabolites ethyl palmitate and ethyl oleate) led to a significant inhibition in mitochondrial TPP uptake, which was associated with a decreased expression of MTPPT protein, mRNA, and activity of the SLC25A19 promoter. Similarly, chronic alcohol feeding of mice led to a significant inhibition in expression of MTPPT protein, mRNA, heterogeneous nuclear RNA, as well as in activity of SLC25A19 promoter in PAC. While chronic alcohol exposure did not affect DNA methylation of the Slc25a19 promoter, a significant decrease in histone H3 euchromatin markers and an increase in H3 heterochromatin marker were observed. These findings show, for the first time, that chronic alcohol exposure negatively impacts pancreatic MTPPT, and that this effect is exerted, at least in part, at the level of Slc25a19 transcription and appears to involve epigenetic mechanism(s).

关键词： 线辣椒-玉米套作   产量   抗逆性  

摘要： 研究线辣椒-玉米套作在正安县中低海拔区域对产量及抗逆性的影响,目的在于发现此类种植新技术的优势并掌握正确的操作方法,为推动农业产业结构调整提供技术支持。介绍线辣椒-玉米套作的优势,分析试验测试的结果,提出在实践操作中应注意的几个环节分别为选种、育苗、定植规格及田间管理。

关键词： 螺旋线   变压器   长脉冲   脉冲功率  

摘要： 提出了采用渐开线硅钢叠片的变压器磁芯与螺旋线的一体化的长脉冲产生结构;计算了螺旋线引入磁芯后,电磁波延迟传输的慢波系数和波阻抗参数,以及脉冲形成的输出参数,并开展了数值模拟进行验证。研究结果表明:引入磁芯后,螺旋线上慢波传输时,内外筒电流沿磁芯基底而非磁芯表面;磁芯的径向厚度相对磁芯径向尺寸越小,磁芯对脉冲形成的影响越小。

关键词： 变截面梁   计算长度系数法   矩阵位移法   屈曲因子   抗侧刚度   临界荷载  

摘要： 对顶层抽柱的四层三跨钢框架进行屈曲分析,采用传统计算长度系数法计算层抗侧刚度,并与SAP2000软件计算的层抗侧刚度比较发现,施加水平荷载求得的各层剪力之比与采用临界荷载方法计算的层抗侧刚度之比相等时,两者结果接近。对钢框架进行整体屈曲分析,指出第1屈曲模态对应的是薄弱层的屈曲,第2及以上屈曲模态因不能正确反映框架梁对框架柱的约束,不能直接加以应用。顶层抽柱导致屋面梁轴力加大,自身临界荷载降低,使得屋面梁对顶层柱的转动约束作用减小或消失,需要在顶层柱计算长度系数计算中予以考虑。

关键词： Tomato   Drying   Antioxidative activity   Color   Quality  

摘要： Drying behavior, moisture sorption isotherm (MSI), glass transition temperatures (Tg) and different quality parameters of tomato (Lycopersicon esculentum L.) as affected by drying (sun and solar) was investigated. Drying of tomato under sun displayed a higher rate of moisture loss than those dried in solar drier. However, both the samples finished the drying process after 52 h. Sun and solar dried tomatoes displayed a Tg of -12 A degrees C. When tested against different water activities (Aw), Tg decreased with an increase of Aw. MSI revealed that the relation between Aw and moisture content was found to be exponential (y = 15.959e(1.5175x), R-2 = 0.9944). Analysis of different quality parameters and antioxidative activity revealed that drying process was known to decrease lycopene, vitamin C, total phenolic and flavonoid content as well as decreased activities was displayed in different antioxidative assays when compared to fresh tomato. Among the samples dried under sun and inside solar drier, there was no significant difference in lycopene and vitamin C content (p < 0.05). However, total phenolic and flavonoid content was higher in solar dried samples. Moreover, antioxidative activity also did not display any difference between the two samples (p < 0.05). More importantly sensory evaluation showed that consumer panelist preferred sun dried samples over solar dried samples. Sun dried sample were more bright red in color with higher a* and L* values than solar dried samples which were darker in color. Therefore, sun drying with some modification can be a promising technique to preserve the perishable tomato and can be effective in preventing the quality losses during drying.

关键词： ATMOSPHERIC temperature   MOLECULAR structure of water   ADSORPTION   MOLECULAR sieves   REACTOR fuel reprocessing   STATISTICAL thermodynamics  

摘要： This work is part of our continuing efforts to address engineering issues related to the removal of tritiated water from off-gases produced in used nuclear fuel reprocessing facilities. In the current study, adsorption equilibrium of water on molecular sieve 3A beads was investigated. Adsorption isotherms for water on the UOP molecular sieve 3A were measured by a continuous-flow adsorption system at 298, 313, 333, and 353 K. Experimental data collected were analyzed by the Generalized Statistical Thermodynamic Adsorption (GSTA) isotherm model. The K+/Na+ molar ratio of this particular type of molecular sieve 3A was similar to 4:6. Our results showed that the GSTA isotherm model worked very well to describe the equilibrium behavior of water adsorption on molecular sieve 3A. The optimum number of parameters for the current experimental data was determined to be a set of four equilibrium parameters. This result suggests that the adsorbent crystals contain four energetically distinct adsorption sites. In addition, it was found that water adsorption on molecular sieve 3A follows a three-stage adsorption process. This three-stage adsorption process confirmed different water adsorption sites in molecular sieve crystals. The second adsorption stage is significantly affected by the K+/Na+ molar ratio. In this stage, the equilibrium adsorption capacity at a given water vapor pressure increases as the K+/Na+ molar ratio increases.

关键词： Microdisc   Microcylinder   Wire electrode   Microwire electrode   Nanoparticle detection   Nanoparticle voltammetry   Ultra-low concentration   Nano-impacts  

摘要： We derive approximate expressions for the average number of diffusive impacts/hits of nanoparticles on microdisc and microwire electrodes for the case where the impact leads to the loss of the nanoparticles from solution either via irreversible adsorption or complete electro-dissolution. The theory can also be applied to sub-micrometre size electrodes (nano-electrodes). The resulting equations can be utilised to analyse the number of impacts and its variance in the 'nano-impact' experiment We also provide analytical expressions for the first passage time of an impact for dilute nanoparticle solutions in the continuum limit of Fickian diffusion. The expressions for the first passage times are used to estimate the lower limit of detection in ultra-dilute nanoparticle solutions for typical nano-impact experiments, and show the advantage of using microwire electrodes in ultra-dilute solutions or solutions containing larger nano-particles. (C) 2015 Elsevier B.V. All rights reserved.

关键词： Animals   Apoptosis/radiation effects   Cell Cycle/radiation effects   Cell Line   Cell Survival/radiation effects   Electromagnetic Fields*   Electromagnetic Fields*   Male   Mice   MicroRNAs/genetics*   MicroRNAs/genetics*   MicroRNAs/metabolism   MicroRNAs/metabolism   Signal Transduction/genetics   Signal Transduction/radiation effects*   Spermatocytes/metabolism   Spermatocytes/radiation effects*  

摘要： Extremely low-frequency electromagnetic fields (ELF-EMFs) can affect male reproductive function, but the underlying mechanism of this effect remains unknown. miRNA-mediated regulation has been implicated as an important epigenetic mechanism for regulatory pathways. Herein, we profiled miRNA expression in response to ELF-EMFs in vitro. Mouse spermatocyte-derived GC-2 cells were intermittently exposed to a 50 Hz ELF-EMF for 72 h (5 min on/10 min off) at magnetic field intensities of 1 mT, 2 mT and 3 mT. Cell viability was assessed using the CCK-8 assay. Apoptosis and the cell cycle were analyzed with flow cytometry. miRNA expression was profiled using Affymetrix Mouse Genechip miRNA 3.0 arrays. Our data showed that the growth, apoptosis or cell cycle arrest of GC-2 cells exposed to the 50 Hz ELF-EMF did not significantly change. However, we identified a total of 55 miRNAs whose expression significantly changed compared with the sham group, including 19 differentially expressed miRNAs (7 miRNAs were upregulated, and 12 were downregulated) in the 1 mT exposure group and 36 (9 miRNAs were upregulated, and 27 were downregulated) in the 3 mT exposure group. The changes in the expression of 15 selected miRNAs measured by real-time PCR were consistent with the microarray results. A network analysis was used to predict core miRNAs and target genes, including miR-30e-5p, miR-210-5p, miR-196b-5p, miR-504-3p, miR-669c-5p and miR-455-3p. We found that these miRNAs were differentially expressed in response to different magnetic field intensities of ELF-EMFs. GO term and KEGG pathway annotation based on the miRNA expression profiling results showed that miRNAs may regulate circadian rhythms, cytokine-cytokine receptor interactions and the p53 signaling pathway. These results suggested that miRNAs could serve as potential biomarkers, and the miRNA-mediated regulation of signaling pathways might play significant roles in the biological effects of ELF-EMFs.