基于笔形束散射核的非均匀模体透射平面散射线分析

目的:利用蒙特卡罗方法分析透射平面上散射光子的物理性质以及非均匀模体厚度对散射核的影响,为基于电子射野影像设备（EPID）的在体剂量验证研究提供基础。方法:利用EGSnrc建立笔形束散射核模型,并模拟获得X射线穿过非均匀模体（水肺水/水骨水模体）以及相应等效厚度水模后30 cm处透射平面上的多种散射线能量注量分布,并分析水肺水/水骨水模体与其等效厚度水模体在散射线能量注量分布上的差异。结果:散射核中一阶康普顿散射线最大能量注量在1×10-4 MeV·cm-2数量级,当离轴距离为8~12 cm时下降至最大值的一半,而散射核中其它散射线能量注量最大值在1×10-5 MeV·cm-2数量级附近或以下。对于水肺水/水骨水模体,散射核能量注量相对偏差变化为±1.2%~±11.5%,且随模体非均匀层厚度增大而增大。结论:散射核中一阶康普顿散射线占比最大,同时也贡献了大部分能量注量相对偏差,在通过散射核来重建非均匀模体后EPID平面上的射线分布时,应着重考虑一阶康普顿散射线对重建结果的影响,并对其进行有效的修正。     

Prediction of Rockfill Materials’ Shear Strength Using Various Kernel Function-Based Regression Models—A Comparative Perspective

The mechanical behavior of the rockfill materials (RFMs) used in a dam’s shell must be evaluated for the safe and cost-effective design of embankment dams. However, the characterization of RFMs with specific reference to shear strength is challenging and costly, as the materials may contain particles larger than 500 mm in diameter. This study explores the potential of various kernel function-based Gaussian process regression (GPR) models to predict the shear strength of RFMs. A total of 165 datasets compiled from the literature were selected to train and test the proposed models. Comparing the developed models based on the GPR method shows that the superlative model was the Pearson universal kernel (PUK) model with an R-squared (R²) of 0.9806, a correlation coefficient (r) of 0.9903, a mean absolute error (MAE) of 0.0646 MPa, a root mean square error (RMSE) of 0.0965 MPa, a relative absolute error (RAE) of 13.0776%, and a root relative squared error (RRSE) of 14.6311% in the training phase, while it performed equally well in the testing phase, with R² = 0.9455, r = 0.9724, MAE = 0.1048 MPa, RMSE = 0.1443 MPa, RAE = 21.8554%, and RRSE = 23.6865%. The prediction results of the GPR-PUK model are found to be more accurate and are in good agreement with the actual shear strength of RFMs, thus verifying the feasibility and effectiveness of the model.     

加味桃红四物汤治疗冠心病心绞痛47例

冠心病心绞痛是由于冠状动脉粥样硬化导致管腔狭窄或冠状动脉痉挛，使心肌缺血、缺氧引起胸部发作性疼痛或不适的严重症状。其发病率明显增高，发病年龄也逐渐年轻化，尤其多发于中老年人。笔者自2004年以来采用桃红四物汤加味治疗冠心病心绞痛47例，取得了较好的疗效，现报告如下。     

桃仁脂肪酸GC-MS指纹图谱研究

目的：对桃仁脂肪酸进行气相色谱指纹图谱研究,为桃仁的质量评价提供依据。方法：利用毛细管气相色谱对桃仁脂肪酸进行分析,并利用GC-MS 技术确认指纹图谱中的特征指纹信息,进行系统聚类和相似度分析。结果：对34批不同产地、品种的桃仁进行了测定,获得了较为理想的包含特征信息的桃仁GC 指纹图谱。结论：本方法重复性好,所建立的指纹图谱为桃仁药材的质量控制提供了有效手段。     

基于微粒群优化算法和支持向量机的软测量建模

在分析基本微粒群优化算法(PSO)和支持向量机(SVM)原理的基础上,采用带有末位淘汰机制的微粒群优化算法优化支持向量机的参数,建立了延迟焦化装置粗汽油干点软测量的微粒群支持向量机模型.该方法利用支持向量机结构风险最小化原则和PSO算法快速全局优化的特点,用于软测量建模.仿真实验表明:所建模型的泛化性能较好,模型具有较高的精度.     

野桃树根对肝癌细胞毒作用的实验研究

目的：探讨野桃树根对肝癌细胞毒作用。方法：肝癌细胞株与野桃树根浸出液共同体外培养,MTT法测细胞毒作用。结果：0.2%,0.1%,0.05%,0.025%浓度的野桃树根浸出液对SMMC7721细胞的抑制率分别为77.97%,64.06%,36.34%,33.75%;0.2%,0.1%,0.05%,0.025%,0.0125%浓度的野桃树根浸出液对SK-HEP-1细胞的抑制率分别为100%,100%,100%,88.98%,82.64%。结论：野桃树根浸出液在体外对肝癌细胞有较强的杀伤作用。     

离子法测定中蒙药材苦杏仁中六种阴离子的含量

目的: 建立一种同时测定中蒙药苦杏仁药材中F^－、Cl^－、Br^－、NO^－₃ 、SO2^－₄ 、PO^3－₄ 阴离子的含量测定方
法。方法:采用离子色谱法、阴离子色谱柱、氢氧化钠梯度淋洗、电导检测苦杏仁6 种无机阴离子。结果: F^－、
Cl^－、Br^－、NO^－₃ 、SO₂^－4 、PO^3－₄ 的加样回收率介于97%～ 102%,苦杏仁中F－、Cl－、Br－、NO－3 、SO2－4 、PO3－
4 重复性良好,含量分别为0．057%0．084%,0．063%,0．070%,0．30%,0．12%。结论: 离子色谱法可以同时检测苦杏仁中6 种阴离
子,灵敏度高,结果准确可行,为苦杏仁的质量控制提供了一种简便快速的方法．     

γ-Zeins are essential for endosperm modification in quality protein maize

Essential amino acids like lysine and tryptophan are deficient in corn meal because of the abundance of zein storage proteins that lack these amino acids. A natural mutant, opaque 2 (o2) causes reduction of zeins, an increase of nonzein proteins, and as a consequence, a doubling of lysine levels. However, o2’s soft inferior kernels precluded its commercial use. Breeders subsequently overcame kernel softness, selecting several quantitative loci (QTLs), called o2 modifiers, without losing the high-lysine trait. These maize lines are known as “quality protein maize” (QPM). One of the QTLs is linked to the 27-kDa γ-zein locus on chromosome 7S. Moreover, QPM lines have 2- to 3-fold higher levels of the 27-kDa γ-zein, but the physiological significance of this increase is not known. Because the 27- and 16-kDa γ-zein genes are highly conserved in DNA sequence, we introduced a dominant RNAi transgene into a QPM line (CM105Mo2) to eliminate expression of them both. Elimination of γ-zeins disrupts endosperm modification by o2 modifiers, indicating their hypostatic action to γ-zeins. Abnormalities in protein body structure and their interaction with starch granules in the F1 with Mo2/+; o2/o2; γRNAi/+ genotype suggests that γ-zeins are essential for restoring protein body density and starch grain interaction in QPM. To eliminate pleiotropic effects caused by o2, the 22-kDa α-zein, γ-zein, and β-zein RNAis were stacked, resulting in protein bodies forming as honeycomb-like structures. We are unique in presenting clear demonstration that γ-zeins play a mechanistic role in QPM, providing a previously unexplored rationale for molecular breeding.     

"苦杏仁"更名为"杏仁"的商榷

通过考释“苦杏仁”与“杏仁”的源流,发现现代有关中药著作及《药典》中“苦杏仁”既未遵照古代主要本草命名传统,也未参考临床用药习惯,其命名欠妥,建议应以“杏仁”作为正名。     

不同产地薏苡仁资源营养成分分析与评价

目的对我国12个薏苡主产区薏苡仁资源的营养品质进行分析与评价,为薏苡资源的合理开发利用提供基础资料。方法采用常规生化分析方法。结果13种薏苡仁营养成分的平均值为:蛋白质15.80%,脂肪5.49%,均高于米、面;碳水化合物63.05%,低于米、面;粗纤维和灰分分别为1.75%与1.68%。薏苡仁的Ca含量丰富,高于米、面;VB1、VB2、VB6、Fe、Zn、Se平均含量与米、面相当。薏苡仁的谷氨酸、亮氨酸含量丰富,均高于米、面;赖氨酸含量较低;但含硫氨基酸平均含量丰富,为6.05mg/g,均高于米、面。以AAS为标准,13个样品中,赖氨酸为第一限制性氨基酸,第二限制性氨基酸随产地不同而异,云南产等8个样品为苏氨酸,四川产等5个样品为异亮氨酸,贵州产为缬氨酸。平均EAA/TAA、EAA/NEA值分别为35.86%、55.91%,平均EAAI值58.91%。结论我国薏苡资源营养较齐全,蛋白质具有较好的氨基酸组成,属于较优质蛋白质。