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1.
Ping-Chi Hsu Jia-Ying Jhong Li-Ping Huang Kuo-Hsin Lee Hsin-Pao Chen Yue-Leon Guo 《International journal of molecular sciences》2021,22(8)
Di(2-ethylhexyl) phthalate (DEHP) is widely used as a plasticizer in the manufacture of polyvinylchloride plastics and has been associated with concerns regarding male reproductive toxicity. In this study, we hypothesized that maternal exposure to DEHP induces transgenerational inheritance of adult-onset adverse reproductive outcomes through the male germline in the F1, F2, and F3 generations of male offspring. Pregnant rats were treated with 5 or 500 mg of DEHP/kg/day through gavage from gestation day 0 to birth. The offspring body weight, anogenital distance (AGD), anogenital index (AGI), sperm count, motility, and DNA fragmentation index (DFI) were measured for all generations. Methyl-CpG binding domain sequencing was performed to analyze sperm DNA methylation status in the F3. DEHP exposure at 500 mg/kg affected AGD, AGI, sperm count, mean DFI, and %DFI in the F1; AGD, sperm count, and mean DFI in the F2; and AGD, AGI, mean DFI, and %DFI in the F3. DEHP exposure at 5 mg/kg affected AGD, AGI, sperm count, and %DFI in the F1; sperm count in the F2; and AGD and AGI in F3. Compared with the control group, 15 and 45 differentially hypermethylated genes were identified in the groups administered 5 mg/kg and 500 mg/kg DEHP, respectively. Moreover, 130 and 6 differentially hypomethylated genes were observed in the groups administered 5 mg/kg and 500 mg/kg DEHP. Overall, these results demonstrated that prenatal exposure to DEHP caused transgenerational epigenetic effects, which may explain the observed phenotypic changes in the male reproductive system. 相似文献
2.
This paper proposes a method for the coordinated control of power factor by means of a multiagent approach. The proposed multiagent system consists of two types of agent: single feeder agent (F_AG) and bus agent (B_AG). In the proposed system, an F_AG plays as an important role, which decides the power factors of all distributed generators by executing the load flow calculations repeatedly. The voltage control strategies are implemented as the class definition of Java into the system. In order to verify the performance of the proposed method, it has been applied to a typical distribution model system. The simulation results show that the system is able to control very violent fluctuation of the demands and the photovoltaic (PV) generations. 相似文献
3.
《Food Control》2015
The aim of the study was to investigate annual and regional differences in the level of aflatoxin B1 (AFB1) in grains and dairy cattle feed. Maize (n = 972), wheat (n = 201), barley (n = 147), oat (n = 136), grain mixtures (n = 168), and dairy cattle feed (n = 325) were sampled from 2009 to 2013 on different farms and in different farm factories situated in four Croatian regions. The samples were analysed for AFB1 using the validated ELISA immunoassay. AFB1 was determined in 16.4% of all investigated samples, among which maize was proven to be the most contaminated, with 21.7% of the samples recovered during 2013 harbouring AFB1 in concentrations over the permissible ones. Levels higher than permitted were observed in 17.9% and 12.3% of grain mixtures and dairy cattle feed, respectively, whereas concentrations of AFB1 determined in other crops throughout the investigated period met the stipulated requirements. The results revealed the AFB1 occurrence to be significantly (p < 0.05) dependent on the cultivation region, with the highest levels generally found in maize harvested in 2013 and consequently in grain mixtures and cattle feed that can most likely be associated with climatic conditions as the most critical factor for mould formation, and thus also AFB1 production. 相似文献
4.
5.
This article presents a new method for pairing devices securely. The commitment-based authentication uses a fuzzy secret that the devices only know approximately. Its novel feature is time-based opening of commitments in a single round. We also introduce a new source for the fuzzy secret: synchronized drawing with two fingers of the same hand on two touch screens or surfaces. The drawings are encoded as strings and compared with an edit-distance metric. A prototype implementation of this surprisingly simple and natural pairing mechanism shows that it accurately differentiates between true positives and man-in-the-middle attackers. 相似文献
6.
In vivo Kinetic Biodistribution of Nano‐Sized Outer Membrane Vesicles Derived from Bacteria
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Su Chul Jang Sae Rom Kim Yae Jin Yoon Kyong‐Su Park Ji Hyun Kim Jaewook Lee Oh Youn Kim Eun‐Jeong Choi Dae‐Kyum Kim Dong‐Sic Choi Yoon‐Keun Kim Jaesung Park Dolores Di Vizio Yong Song Gho 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(4):456-461
Evaluation of kinetic distribution and behaviors of nanoparticles in vivo provides crucial clues into their roles in living organisms. Extracellular vesicles are evolutionary conserved nanoparticles, known to play important biological functions in intercellular, inter‐species, and inter‐kingdom communication. In this study, the first kinetic analysis of the biodistribution of outer membrane vesicles (OMVs)—bacterial extracellular vesicles—with immune‐modulatory functions is performed. OMVs, injected intraperitoneally, spread to the whole mouse body and accumulate in the liver, lung, spleen, and kidney within 3 h of administration. As an early systemic inflammation response, increased levels of TNF‐α and IL‐6 are observed in serum and bronchoalveolar lavage fluid. In addition, the number of leukocytes and platelets in the blood is decreased. OMVs and cytokine concentrations, as well as body temperature are gradually decreased 6 h after OMV injection, in concomitance with the formation of eye exudates, and of an increase in ICAM‐1 levels in the lung. Following OMV elimination, most of the inflammatory signs are reverted, 12 h post‐injection. However, leukocytes in bronchoalveolar lavage fluid are increased as a late reaction. Taken together, these results suggest that OMVs are effective mediators of long distance communication in vivo. 相似文献
7.
仪器仪表产品的脉冲耐压试验是产品型式试验、例行试验中的基本内容。通过对GB4793.1标准的整理,归纳了仪器仪表产品的脉冲耐压试验要求。通过对试验方法和设备特性的梳理,总结了特性参数,并介绍了应对脉冲耐压试验可采取的保护器件的类别及选用方法。 相似文献
8.
针对模拟电路健康管理的特点,提出了一种基于PSO优化多核RVM的模拟电路故障预测方法。利用参数分析得到电路的输出频域响应作为特征,计算其与电路无故障标准响应的欧氏距离来表征电路元件健康值,将多个核函数线性组合,并用PSO优化多核RVM参数后的模型实现对各个时间点元件的健康值变化轨迹进行预测。仿真结果表明,该方法在小样本情况下,预测效果优于单一核函数的RVM模型,适用于健康管理中实时预测,具有较好的实用性。 相似文献
9.
为了减小传统的最差情况设计方法引入的电压裕量,提出了一种变化可知的自适应电压缩减(AVS)技术,通过调整电源电压来降低电路功耗.自适应电压缩减技术基于检测关键路径的延时变化,基于此设计了一款预错误原位延时检测电路,可以检测关键路径延时并输出预错误信号,进而控制单元可根据反馈回的预错误信号的个数调整系统电压.本芯片采用SMIC180 nm工艺设计验证,仿真分析表明,采用自适应电压缩减技术后,4个目标验证电路分别节省功耗12.4%,11.3%,10.4%和11.6%. 相似文献
10.
Reducing the complexity of distance measurement methods for circular turbo codes that use structured interleavers
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Youssouf Ould‐Cheikh‐Mouhamedou 《International Journal of Communication Systems》2015,28(9):1572-1579
The knowledge of turbo code's minimum Hamming distance (dmin) and its corresponding codeword multiplicity (Amin) is of a great importance because the error correction capability of a code is strongly tied to the values of dmin and Amin. Unfortunately, the computational complexity associated with the search for dmin and Amin can be very high, especially for a turbo code that has high dmin value. This paper introduces some useful properties of turbo codes that use structured interleavers together with circular encoding. These properties allow for a significant reduction of search space and thus reduce significantly the computational complexity associated with the determination of dmin and Amin values. © 2014 The Authors. International Journal of Communication Systems published by John Wiley & Sons, Ltd. 相似文献