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991.
水管体制改革是当前水利管理中的一项十分重要的工作。就安徽来说,省管工程管理体制改革进展较快,市县水管体制改革进展相对较慢、发展不平衡。本文就如何做好水管体制改革提出了具体意见。 相似文献
992.
Lei Li Meng-Qi Zhang Xiao Sun Wen-Ying Liu Zhi-Li Huang Yi-Qun Wang 《International journal of molecular sciences》2022,23(3)
Good sleep quality is essential for maintaining the body’s attention during wakefulness, which is easily affected by external factors such as an ambient temperature. However, the mechanism by which an ambient temperature influences sleep–wake behaviors remains unclear. The dorsomedial hypothalamus (DMH) has been reported to be involved in thermoregulation. It also receives projection from the preoptic area, which is an important region for sleep and energy homeostasis and the suprachiasmatic nucleus—a main control area of the clock rhythm. Therefore, we hypothesized that the DMH plays an important role in the regulation of sleep related to ambient temperatures. In this study, we found that cold exposure (24/20/16/12 °C) increased wakefulness and decreased non–rapid eye movement (NREM) sleep, while warm exposure (32/36/40/44 °C) increased NREM sleep and decreased wakefulness compared to 28 °C conditions in wild-type mice. Then, using non-specific and specific apoptosis, we found that lesions of whole DMH neurons and DMH γ–aminobutyric acid (GABA)-ergic neurons induced by caspase-3 virus aggravated the fluctuation of core body temperature after warm exposure and attenuated the change in sleep–wake behaviors during cold and warm exposure. However, chemogenetic activation or inhibition of DMH GABAergic neurons did not affect the sleep–wake cycle. Collectively, our findings reveal an essential role of DMH GABAergic neurons in the regulation of sleep–wake behaviors elicited by a change in ambient temperature. 相似文献
993.
Yansong Ji Xiaoning Zhang Zhenyu Chen Yuting Xiao Shiwei Li Jie Gu Hongmei Hu Guotao Cheng 《International journal of molecular sciences》2022,23(3)
The recycling and reuse of biomass waste for the preparation of carbon-based adsorbents is a sustainable development strategy that has a positive environmental impact. It is well known that a large amount of silk sericin (SS) is dissolved in the wastewater from the silk industry. Utilizing the SS instead of discharging it into the environment without further treatment would reduce environmental and ecological problems. However, effective enrichment of the SS from the aqueous solution is a challenge. Here, with the help of carboxymethyl chitosan (CMCS), which can form a gel structure under low voltage, an SS/CMCS hydrogel with SS as the major component was prepared via electrodeposition at a 3 V direct-current (DC) voltage for five minutes. Following a carbonization process, an SS-based adsorbent with good performance for the removal of methylene blue (MB) from an aqueous solution was prepared. Our results reveal that the SS/CMCS hydrogel maintains a porous architecture before and after carbonization. Such structure provides abundant adsorption sites facilitating the adsorption of MB molecules, with a maximum adsorptive capacity of 231.79 mg/g. In addition, it suggests that the adsorption is an exothermic process, has a good fit with the Langmuir model, and follows the intra-particle diffusion model. The presented work provides an economical and feasible path for the treatment of wastewater from dyeing and printing. 相似文献
994.
Kai Yang Zhupeng Xiao Xueai He Ruotong Weng Xinyue Zhao Taolei Sun 《International journal of molecular sciences》2022,23(3)
Pannexins (PANX) were cloned based on their sequence homology to innexins (Inx), invertebrate gap junction proteins. Although there is no sequence homology between PANX and connexins (Cx), these proteins exhibit similar configurations. The PANX family has three members, PANX1, PANX2 and PANX3. Among them, PANX1 has been the most extensively studied. The PANX1 channels are activated by many factors, including high extracellular K+ ([K+]e), high intracellular Ca2+ ([Ca2+]i), Src family kinase (SFK)-mediated phosphorylation, caspase cleavage and mechanical stimuli. However, the mechanisms mediating this mechanosensitivity of PANX1 remain unknown. Both force-from-lipids and force-from-filaments models are proposed to explain the gating mechanisms of PANX1 channel mechanosensitivity. Finally, both the physiological and pathological roles of mechanosensitive PANX1 are discussed. 相似文献
995.
为了利用”凝视视觉几何约束”的信息来确定移动机器人的位置和方位角,就需要解决数据融合的问题。”几何约束”不是来自真实传感器的直接可测量的数据,这种特殊形式的信息不能被直接融合。为此目的,该文提出了一种融合特殊形式信息的新途径,也即利用”软传感器”的方法来融合来自”几何约束”的信息。软传感器的输出与其它真实传感器的输出一起经过扩展信息滤波器最终实现融合。文中最后提供了利用该方法进行移动机器人定位的计算机仿真例子。仿真结果表明了软传感器信息融合方法的可行性和有效性。软传感器可以广泛应用在很多类似的信息融合问题中。 相似文献
996.
计算机数字图像处理常用颜色空间及其转换 总被引:2,自引:0,他引:2
在图像的显示和数字图像处理过程中,考虑到图像输出效果及图像处理精度,需要根据不同的实际要求使用不同的颜色空间。阐述了数字图像处理过程中涉及到的和显示领域经常使用到的几个颜色空间,重点讨论了实际使用中RGB和HIS颜色空间的转换关系。 相似文献
997.
功率控制系统是反应堆的关键控制系统之一,对保证反应堆安全和稳定运行起着极其重要的作用。设计良好的熔盐堆功率控制器应具有及时的瞬态响应特性,需要简单可靠的控制方法以保证控制器的响应速度和安全性。本文基于线性自抗扰控制(Linear Active Disturbance Rejection Control,LADRC)理论设计了应用于熔盐堆(Molten Salt Reactor,MSR)的反应堆功率控制器,导出了用于自抗扰控制器设计的相对功率的二阶线性微分方程和对应的线性扩张状态观测器(Linear Extended State Observer,LESO)。最终,通过仿真得到的结果表明:该控制器模型适用于熔盐堆功率的控制,具有较快的调节速度和精度,且对测量噪声不敏感,有良好的抗扰效果。 相似文献
1000.