采用傅里叶红外光谱法(fT-IR)获取样品红外指纹图谱,利用人工神经网络误差反向传播算法(BP-ANN)建立八角茴香(Illicium verum Hook.f.)的红外指纹模型。结果表明,该方法可有效鉴别八角茴香和伪八角,与传统鉴别方法结果基本一致,但更直...
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采用傅里叶红外光谱法(fT-IR)获取样品红外指纹图谱,利用人工神经网络误差反向传播算法(BP-ANN)建立八角茴香(Illicium verum Hook.f.)的红外指纹模型。结果表明,该方法可有效鉴别八角茴香和伪八角,与传统鉴别方法结果基本一致,但更直接和快速。该方法可为八角茴香的鉴别提供借鉴和参考。
对四川、广西、海南、浙江4地的八角属植物中莽草酸的含量进行了测定,得到广西产八角茴香(Illicium verum Hook.f.)中莽草酸含量最高,为12.61%。对莽草酸的两种提取工艺进行了比较,得到水提取工艺效果较好,有利于莽草酸的后续纯化,最佳...
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对四川、广西、海南、浙江4地的八角属植物中莽草酸的含量进行了测定,得到广西产八角茴香(Illicium verum Hook.f.)中莽草酸含量最高,为12.61%。对莽草酸的两种提取工艺进行了比较,得到水提取工艺效果较好,有利于莽草酸的后续纯化,最佳工艺为按水料质量比10∶1加水回流提取1.5 h,提取3次。莽草酸的纯化工艺有萃取法、阳离子树脂交换法、阴离子树脂交换法、硅胶吸附法等,其各有利弊,综合分析以树脂交换法为佳。
AIM To investigate the effects and mechanism of polygalasaponin f (PS-f) on PC12 cellular apoptosis induced by 1-methyl-4-phenylpyridinium ion (MPP +).METHODS The cell viability was evaluated using MTT *** cell apopto...
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AIM To investigate the effects and mechanism of polygalasaponin f (PS-f) on PC12 cellular apoptosis induced by 1-methyl-4-phenylpyridinium ion (MPP +).METHODS The cell viability was evaluated using MTT *** cell apoptosis rate was analyzed using flow *** reactive oxygen species (ROS) was examined using DCfH-DA, the ATP depletion was examined using a luciferase-coupled quantification ***-1 staining was used to detect the mitochondrial membrane potential (MMP).Western blot analysis was used to determine cytochrome c and caspase *** PS-f increased the viabihty of PC12 cells,decreased MPP +-induced apoptosis, restored MPP +-induced mitochondrial dysfunction and suppressed the expression of cytochrome c and active-caspase ***-f showed a dose-dependent manner in all the *** PS-f protects PC12 cells against MPP +-induced apoptosis via ameliorating the mitochondrial ***, PS-f may be a potential bioactive compound for the treatment of Parkinson's disease.
Lower budgets and greater competition in the defense industry put a strain on defense organizations. Occurring at the same time was a greater emphasis on diversity, inclusion, and technology to engage and retain the e...
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Lower budgets and greater competition in the defense industry put a strain on defense organizations. Occurring at the same time was a greater emphasis on diversity, inclusion, and technology to engage and retain the existing workforce while attracting new employees to address growing competition in the market. Unique cultures within the defense industry created significant barriers to having the resources to maintain high performance. The failure of leaders to understand the cultures that are part of the organization may have led to poor organizational decisions affecting trust and collaboration. This study found that the military culture, when left unmanaged, created barriers within the organization. The military culture had a pervasive effect on the communication within defense organizations, the structure of defense organizations, and the culture of the organization. While having a greater understand of the defense culture is important to being successful in the defense industry, leaders must understand and manage the effect the culture has on the performance of the organization and its employees. As the market shifts toward commercial suppliers and international customers, leaders need to address the culture and organization of the company to ensure the company is ready to address the market successfully.
In this study,I examine the properties of positive and negative aggregate earnings changes and how they relate to contemporaneous market returns. I find that the negative relationship between aggregate earnings news a...
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In this study,I examine the properties of positive and negative aggregate earnings changes and how they relate to contemporaneous market returns. I find that the negative relationship between aggregate earnings news and market returns,documented in Kothari et al. (2006) and Cready and Gurun (2010),is driven primarily by bad news observations. I also find that negative aggregate earnings changes mean revert in the two quarters following the negative aggregate earnings changes quarter. Market returns increase contemporaneously with negative aggregate earnings news,suggesting that investors incorporate the expectation of mean reversion for negative aggregate earnings changes in subsequent quarters. As a result,the aggregate earnings news market returns relationship is negative when aggregate earnings news is negative. When aggregate earnings news is positive,I find that market returns are positively associated with aggregate earnings news. Since aggregate earnings news consists of cash flow and discount rate news components,each having an opposite direction effect on market return,the cash flow news component dominates the discount rate news component when aggregate earnings news is positive,while the discount rate news component dominates the cash flow news component when aggregate earnings news is negative.
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