Pollen viability of <i>Polygala paniculata</i> L. (Polygalaceae) using different staining methods

Polygala paniculata L. is a medicinal plant that grows in the Brazilian Atlantic coast, known as ‘barba-de-São-João’, ‘barba-de-bode’, ‘vassourinha branca’, and ‘mimosa’. In this study, pollen viability was estimated by three different staining methods: 2% acetic orcein, 2% acetic carmine, and Alexander’s stain. The young inflorescences of twenty accessions were collected and fixed in a solution of ethanol: acetic acid (3:1) for 24 hours, then stored in ethanol 70% under refrigeration. Six slides per plant, two for each stain, were prepared by squashing, and 300 pollen grains per slide were analyzed. Pollen viability was high (>70%) for most accessions of P. paniculata using the Alexander’s stain, which proved the most adequate method to estimate pollen viability.     

Proteomics analysis provides novel biomarkers and therapeutic target candidates in the treatment of the Huang-Pu-Tong-Qiao formula in an AD rat model

Background: Huang-Pu-Tong-Qiao formula (HPTQ), a traditional Chinese herbal formula, has a variety of pharmacological effects. It has been used to treat Alzheimer’s disease (AD) for decades. This study aimed to screen differentially expressed proteins in the hippocampus of AD model rats treated with HPTQ. Proteomic studies of the effects of HPTQ on AD are key to understanding the therapeutic mechanisms of HPTQ and identifying potential therapeutic targets. Methods: We hence used the isobaric tags for relative and absolute quantification (ITRAQ) approach to investigate the differentially expressed proteins in the hippocampus of AD model rats before and after HPTQ administration and to identify the potential therapeutic target proteins of HPTQ. In this study, the learning and memory abilities of AD rats were examined by the Morris water maze test. After HPTQ administration, the differentially expressed proteins in the hippocampus of AD rats were quantified and analyzed in silico. Furthermore, western blotting was used to verify the expression of related proteins. Results: The Morris water maze results showed that HPTQ could improve the learning and memory ability of AD model rats. The proteomics analysis results showed that 57 proteins were differentially expressed, of which 35 were up-regulated and 22 were down-regulated. Bioinformatics analysis indicated that proteins with altered expression after HPTQ treatment were involved in several biological processes that have the potential to exert neuroprotective effects. These included promoting the translation of ribosomes, improving the deposition of amyloid-beta (Aβ), regulating autophagy, regulating neuronal synaptic function and plasticity, and alleviating oxidative stress. Conclusion: In conclusion, we identified several potential therapeutic target proteins and related mechanistic pathways of HPTQ in the treatment of AD, laying the foundation for further investigation of the therapeutic effects of HPTQ.     

一种新型正铲液压挖掘装置的运动学和动力学分析

提出一种可有效增大铲斗液压缸的推力和行程的新型正铲液压挖掘装载装置。通过对机构自由度分析,验证了该工作装置满足挖掘机铲斗作业要求的一个转动自由度和两个移动自由度。基于模块化图形组态和运动链环路理论,建立该机构的运动学分析流程图,并根据流程图对新型机构进行运动学特性分析。采用数值验证的方法给出五组数值算例,通过运动学正解和反解分析结果的对比,验证了分析方法的可靠性和准确性。基于凯恩方法对该新型机构进行动力学分析,将驱动力等效为关节转矩,推导并建立了动力学数学模型。参考卡特彼勒矿用正铲挖掘机的相关尺寸,给定该新型正铲液压挖掘装载装置的结构参数,基于Matlab分别在空载和变阻力情况下对挖掘机水平作业工况下进行动力学仿真研究,结果验证了动力学模型的准确性。研究结果为该新型机构的设计和应用提供了重要的理论依据。     

Improvement in electrical and thermal behavior of polystyrene/multiwalled carbon nanotubes nanocomposites

Polystyrene (PS)/multiwalled carbon nanotubes (MWCNTs) nanocomposite has been prepared by solvent evaporation technique  and . Tetrahydroforan (THF) has been used as a solvent. Its electrical and thermal properties have been investigated by using LCR meter, 2-probe mechanism and Thermo Gravimetric Analysis Differential Thermal Calorimeter (TGA/DTA) respectively. Increase in dielectric constant and loss is observed with the increase of MWCNTs content in the nanocomposites. Frequency dependent AC conductivity follows the universal power law. Increase in AC conductivity with temperature has been attributed to hopping of π electrons in the MWCNTs. Temperature dependent DC conductivity was found to be a typical of a semi conducting behavior following Mott’s 3-D variable range hoping model. Best fitted Mott’s parameters were determined from the observed data.     

Efficacy of oral consumption of curcumin/ for symptom improvement in inflammatory bowel disease: A systematic review of animal models and a meta-analysis of randomized clinical trials

The roots of the vegetal Curcuma due to its high content of polyphenols, has been used successfully in several clinical situations. This review assessed the effect of curcumin/Curcuma longa on symptoms and metabolic changes in inflammatory bowel disease (IBD). A systematic review of animal models and randomized clinical trials (RCTs) was conducted by searching the following electronic databases: PubMed, CENTRAL, LILACS, Science Direct, and ClinicalTrials.gov. From 997 found records, 62 were included. More than 90% of the animal studies reported an improvement in macroscopic, histologic and/or functional activity; 80% identified decreased oxidative and/or inflammatory biomarkers in animals treated with curcumin. Among the RCTs, intention-to-treat analysis showed that oral curcumin was effective in inducing clinical remission (n = 281, RR: 3.15 CI 95% [1.22–8.10] p = 0.0017; i² = 72.2%, p = 0.006) and clinical response (n = 259, RR: 1.60 CI 95% [1.09–2.35] p = 0.0017; i² = 59.7%, p = 0.042) but not endoscopic remission (n = 161, RR: 2.91 CI 95% [0.58–14.58] p = 0.195; i² = 72.7%, p = 0.026). These results confirm that oral supplementation with curcumin/Curcuma longa has beneficial actions in animal colitis and, when associated with drug therapy, is effective in the treatment of patients with IBD.

     

海相沉积砂岩土壤源热泵供热性能的试验研究

根据海相沉积砂岩——设计了土壤源热泵热水系统.试验采用单因素法,在连续和间歇运行两种工况下研究不同热负荷下系统的运行情况及土壤换热能力(通过控制开启主机的数量和土壤换热井数量来改变热负荷大小);在主机停止工作后,让土壤换热器中的循环介质与大地进行充分换热,测试土壤换热器中循环介质的温度变化来判断埋管区土壤温度场的恢复能力,从而综合评价地源热泵热水系统的运行性能.     

顶空-气相色谱-质谱法测定烟用水基型乳胶中苯系物

建立了烟用水基型乳胶中苯及苯系物的顶空-气相色谱-质谱（HS-GC-MS）分析方法。样品采用 N,N-二甲基甲酰胺溶解,静态顶空进样,气相色谱-质谱-选择离子（SIM）监测法测定5种烟用水基型乳胶的苯、甲苯、对二甲苯、间二甲苯、邻二甲苯及苯乙烯。结果表明：所有组分在0.05～2.0 mg/L范围内线性关系良好,相关系数为0.998 0～0.999 4,检出限为0.01～0.03 mg/kg;6种待测化合物在0.2 μg和1.0 μg两个添加水平的平均回收率可达93.7%～102%,相对标准偏差为4.21%～7.82%。     

Establishing distinctive theories and methods of design science rooted in Chinese traditional culture

Frontiers of Mechanical Engineering - The human social development saw the formation of five unique civilizations, with the latter forming their own distinctive cultures. China’s traditional...