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1.
Ilaria Fraudentali Renato A. Rodrigues-Pousada Riccardo Angelini Sandip A. Ghuge Alessandra Cona 《International journal of molecular sciences》2021,22(10)
Polyamines are ubiquitous, low-molecular-weight aliphatic compounds, present in living organisms and essential for cell growth and differentiation. Copper amine oxidases (CuAOs) oxidize polyamines to aminoaldehydes releasing ammonium and hydrogen peroxide, which participates in the complex network of reactive oxygen species acting as signaling molecules involved in responses to biotic and abiotic stresses. CuAOs have been identified and characterized in different plant species, but the most extensive study on a CuAO gene family has been carried out in Arabidopsis thaliana. Growing attention has been devoted in the last years to the investigation of the CuAO expression pattern during development and in response to an array of stress and stress-related hormones, events in which recent studies have highlighted CuAOs to play a key role by modulation of a multilevel phenotypic plasticity expression. In this review, the attention will be focused on the involvement of different AtCuAOs in the IAA/JA/ABA signal transduction pathways which mediate stress-induced phenotypic plasticity events. 相似文献
2.
Xufen Xie Yingying Shang Jieyu Zhu Ningfang Liao Wenmin Wu Jing Liang Chaoqun Fu 《Color research and application》2021,46(1):65-74
Reconstruction of spectral information based on multi‐channel image system is a significant problem in color reproduction, detection, and recognition. A spectral radiance reconstruction from trichromatic digital camera responses is researched in this article. The mapping relationship between the trichromatic imaging system response and the incident spectral radiance is analyzed. Then, in order to remove the ill‐posedness of the problem, a regularized constraint solution model of spectral radiance reconstruction matrix is established. And the spectral radiance can be reconstructed by spectral radiance reconstruction matrices and trichromatic imaging system response. Finally, the spectral radiance reconstruction matrix is estimated by the system radiometric calibration experiment. The input radiance is offered by a LCD display. A 3‐factor and 9‐level orthogonal test is designed for the calibration experiment, and a test set of 24 colors is used for precision analysis. The results show that the average relative mean error of our method is 8.69%, it is lower than that of Wiener filtering method by 2.84%. The method can reconstruct spectral radiance information effectively. 相似文献
3.
Ruirui Lu Katharina Metzner Fangyuan Zhou Cathrin Flauaus Annika Balzulat Patrick Engel Jonas Petersen Rebekka Ehinger Anne Bausch Peter Ruth Robert Lukowski Achim Schmidtko 《International journal of molecular sciences》2021,22(1)
The sodium-activated potassium channel Slack (KNa1.1, Slo2.2, or Kcnt1) is highly expressed in populations of sensory neurons, where it mediates the sodium-activated potassium current (IKNa) and modulates neuronal activity. Previous studies suggest that Slack is involved in the processing of neuropathic pain. However, mechanisms underlying the regulation of Slack activity in this context are poorly understood. Using whole-cell patch-clamp recordings we found that Slack-mediated IKNa in sensory neurons of mice is reduced after peripheral nerve injury, thereby contributing to neuropathic pain hypersensitivity. Interestingly, Slack is closely associated with ATP-sensitive P2X3 receptors in a population of sensory neurons. In vitro experiments revealed that Slack-mediated IKNa may be bidirectionally modulated in response to P2X3 activation. Moreover, mice lacking Slack show altered nocifensive responses to P2X3 stimulation. Our study identifies P2X3/Slack signaling as a mechanism contributing to hypersensitivity after peripheral nerve injury and proposes a potential novel strategy for treatment of neuropathic pain. 相似文献
4.
Higher transmission rate is one of the technological features of prominently used wireless communication namely Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing (MIMO–OFDM). One among an effective solution for channel estimation in wireless communication system, specifically in different environments is Deep Learning (DL) method. This research greatly utilizes channel estimator on the basis of Convolutional Neural Network Auto Encoder (CNNAE) classifier for MIMO-OFDM systems. A CNNAE classifier is one among Deep Learning (DL) algorithm, in which video signal is fed as input by allotting significant learnable weights and biases in various aspects/objects for video signal and capable of differentiating from one another. Improved performances are achieved by using CNNAE based channel estimation, in which extension is done for channel selection as well as achieve enhanced performances numerically, when compared with conventional estimators in quite a lot of scenarios. Considering reduction in number of parameters involved and re-usability of weights, CNNAE based channel estimation is quite suitable and properly fits to the video signal. CNNAE classifier weights updation are done with minimized Signal to Noise Ratio (SNR), Bit Error Rate (BER) and Mean Square Error (MSE). 相似文献
5.
The deterministic and probabilistic prediction of ship motion is important for safe navigation and stable real-time operational control of ships at sea. However, the volatility and randomness of ship motion, the non-adaptive nature of single predictors and the poor coverage of quantile regression pose serious challenges to uncertainty prediction, making research in this field limited. In this paper, a multi-predictor integration model based on hybrid data preprocessing, reinforcement learning and improved quantile regression neural network (QRNN) is proposed to explore the deterministic and probabilistic prediction of ship pitch motion. To validate the performance of the proposed multi-predictor integrated prediction model, an experimental study is conducted with three sets of actual ship longitudinal motions during sea trials in the South China Sea. The experimental results indicate that the root mean square errors (RMSEs) of the proposed model of deterministic prediction are 0.0254°, 0.0359°, and 0.0188°, respectively. Taking series #2 as an example, the prediction interval coverage probabilities (PICPs) of the proposed model of probability predictions at 90%, 95%, and 99% confidence levels (CLs) are 0.9400, 0.9800, and 1.0000, respectively. This study signifies that the proposed model can provide trusted deterministic predictions and can effectively quantify the uncertainty of ship pitch motion, which has the potential to provide practical support for ship early warning systems. 相似文献
6.
以方竹笋中提取的膳食纤维为研究对象,采用动态高压微射流(dynamic high-pressure micro-fluidization, DHPM)在不同压力条件(0,50,100,150,200 MPa)下进行处理,探究其对竹笋膳食纤维(bamboo shoots dietary fiber, BSDF)理化和结构特性的影响。结果表明,随着处理压力的增大,BSDF粒径先增大后减小,当处理压力为150 MPa时,粒径最小,为(370±11) nm,此条件下BSDF的持水力、持油力和膨胀力达到最大,较对照组分别提高了47.74%,50.54%,61.27%,且差异显著(P<0.05)。红外光谱分析表明DHPM处理不会改变BSDF的官能团,但会使BSDF内部的部分氢键断裂和半纤维素、木质素等发生降解;X射线衍射和热重分析表明DHPM处理不会引起BSDF的晶体结构改变,但晶体有序度会下降,进而导致其热稳定性降低;微观结构分析显示DHPM处理会使BSDF颗粒尺寸减小、表面粗糙、组织松散,且当处理压力为200 MPa时,颗粒发生团聚。综上,DHPM可以有效改善BSDF的理化性质,在膳食纤维改性方面具有一定的应用价值。 相似文献
7.
In this article, an analytical technique is introduced to obtain the excitation coefficients of uniformly spaced linear antenna arrays in order to achieve a desired array factor. By integration of the prescribed array factor, the array factor dependency to the progressive phase shift is eliminated. A new system of linear equations is consequently obtained whose solution represents the excitation coefficients of the array. Some examples are presented to verify the accuracy of the introduced method. The performance of this strategy is compared with those obtained by the other well‐known techniques such as Woodward‐Lawson and Fourier transform. It is shown that the presented method estimates the desired array pattern with a very good precision. 相似文献
8.
9.
为了探究带有方形肋及双倾斜肋片细通道的流动换热及熵产特性,设计了2种带有方形肋及双倾斜肋片的组合细通道(MCDS-L, MCDS-R),然后采用数值模拟的方法分析其流动特性、传热特性和熵产特性,并将其分析结果同2种方形肋细通道(MCS-L, MCS-R)和一种双倾斜肋片细通道(MCD)进行对比。结果表明,在所研究的雷诺数范围内,组合通道的摩擦阻力系数基本一致且均高于其他3组通道(MCS-L, MCS-R, MCD) 。此外,组合通道的努塞尔数均高于其他3组通道,而熵产增大数均低于其他3组通道。其中,MCDS-L通道的努塞尔数最大,熵产增大数最低。表明MCDS-L通道的换热效果最佳,能量的综合利用程度最高。研究成果为微细通道热沉的设计提供参考。 相似文献
10.
针对国内外风电和工业齿轮箱轻量化的设计趋势,较低的安全系数对齿轮齿根弯曲强度提出了更为严格的要求。研究表明,在材料技术和齿形设计难以再优化的情况下,滚齿加工的粗糙度,尤其是齿根部位的粗糙度对齿轮弯曲强度的影响尤为敏感。针对滚齿工艺过程,从滚齿加工参数、刀具前刀面粗糙度和刀具刃口圆角三方面进行分析,验证其对齿根粗糙度的影响。 相似文献