Effect of extraction methods on kinetic,chemical composition and antibacterial activities of Tunisian Thymus vulgaris. L. essential oil

The present study aims to compare two innovative extraction techniques: microwave-assisted hydrodistillation (MAHD) and solvent-free microwave extraction (SFME) through traditional extraction techniques: hydrodistillation (HD) and steam distillation (SD) for their efficiency in the extraction of the volatile compounds from Tunisian Thymus vulgaris leaves; the kinetic, yield, composition and antibacterial activities of the essential oil were assessed in vitro. Results show that the essential oils extracted by microwaves were quantitatively (yield) similar to those obtained through the conventional methods, but qualitatively, essential oils analysed by gas chromatography–mass spectrometry (GC–MS) presented 17, 11, 11 and 8 compounds obtained through SFME, MAHD, SD and HD, respectively, mostly consisting of carvacrol (89.24–41.17%), followed by γ-terpinene (11.37–1.37%) and para-cymene (27.95–2.05%). The essential oils were screened for antibacterial activity against 5 microorganisms. All essential oils obtained by studied extraction methods showed the same resistance against Gram (?) and Gram (+) bacteria. The SFME method gave the best results: rapid kinetic of extraction (30 min vs. 35 min for MAHD, 120 min for SD, and 180 min for HD), less energy saving and cleanest process.     

Analysis of physicochemical properties during the processing of Yiluxian,a traditional chinese low‐salt fish product

Yiluxian, a traditional Chinese low‐salt fish product, has been produced manually for decades. However, its quality depends on worker experience and varies owing to the lack of specific scientific guidelines for uniform production. This study investigated the changes in physicochemical properties under different salt concentrations and explored the principles underlying the low‐salt pickling process. The NaCl content of gutted fish increased to 3.82% in brining, and it decreased significantly to 1.15% after desalting. The colour of Yiluxian was not significantly different from that of raw fish (P > 0.05). The hardness, springiness, resistance and chewiness decreased by 12%, 9%, 27% and 19%, respectively, while cohesiveness did not change significantly (P > 0.05). Furthermore, Yiluxian is preferred over commonly salted fish for superior sensory profile. Our findings demonstrated the changes in various characteristics during pickling were expected to facilitate the stabilisation and uniformity of the quality and industrial production of this traditional food product.     

干燥方式对真姬菇菌柄和菌盖挥发性风味物质的影响

采用电子鼻结合顶空固相微萃取-气相色谱-质谱技术探究热风干燥（60、70、80℃）、冷冻干燥、自然干燥对真姬菇菌柄和菌盖挥发性风味物质的影响,并通过相对气味活度值（relative odor activity value,ROAV）分析各风味物质对干燥样品总体风味的贡献。结果表明：通过电子鼻检测发现这10组样品传感器数值存在明显差异且电子鼻可以对其风味很好地区分。热风干燥（60、70、80℃）、冷冻干燥、自然干燥的菌盖分别鉴定出32、41、40、53、48种风味物质,而菌柄分别鉴定出34、33、33、43、44种风味物质。相同干燥方式处理的菌盖挥发性风味物质含量高于菌柄,相较于自然干燥和冷冻干燥,热风干燥生成了较高含量的新型风味物质。由ROAV分析得出25种风味物质,其中三甲胺、异戊醛、1-辛烯-3-醇风味贡献较大。进一步对这25种风味物质进行主成分分析,建立综合函数品质评价模型,发现热风干燥80℃时制得菌盖样品（g-80℃）评分最高,说明其风味品质最好。     

高效能双线圈音圈电机的设计与分析

针对圆筒型音圈电机轴向充磁永磁体利用率低的缺点,提出应用双层Halbach永磁阵列和双线圈的方式对音圈电机结构进行改进.通过有限元法分析音圈电机中永磁体充磁角度、气隙宽度及永磁体厚度等结构参数对永磁体气隙磁通密度的影响.根据仿真结果对音圈电机的磁路结构和线圈结构进行改进,改进后的音圈电机在保证推力的同时可使磁体利用率提高53%,证明提出结构具有高效性.     

Psychopathy in a noninstitutional sample: Differences in primary and secondary subtypes.

Early theoretical conceptualizations suggest psychopathy is a heterogeneous construct whereby psychopathic individuals are found in diverse populations. The current study examined male and female psychopathy subtypes in a large sample of undergraduate students (n = 1229). Model-based cluster analysis of the Psychopathic Personality Inventory-Short Form (PPI-SF) revealed two clusters in both male and female students. In males, the primary subtype evidenced greater psychopathic personality traits (i.e., Social Potency, Fearlessness, and Impulsive Nonconformity) and lower anxiety (i.e., higher Stress Immunity), whereas the secondary subtype displayed fewer psychopathic personality traits (i.e., Machiavellian Egocentricity and Blame Externalization) and higher anxiety (i.e., lower Stress Immunity). In females, the primary subtype exhibited higher scores across all PPI-SF subscales and lower anxiety whereas the secondary subtype reported lower PPI-SF subscale scores and higher anxiety. Across a diverse array of personality, affective, and behavioral external correlates, differences between the subtypes and with nonpsychopaths emerged. Implications for psychopathy in noninstitutional populations with respect to theory, research, and gender are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Antioxidant Activity of Free and Bound Compounds in Quinoa (Chenopodium quinoa Willd.) Seeds in Comparison with Durum Wheat and Emmer

Abstract: Antioxidant activity (AA) of quinoa (Chenopodium quinoa Willd.) seeds, as well as of durum wheat (Triticum turgidum L. ssp. durum Desf.) and of emmer (T. turgidum L. ssp. dicoccum Schübler) grains, was evaluated by studying hydrophilic (H), lipophilic (L), free‐soluble (FSP) and insoluble‐bound (IBP) phenolic extracts using the new lipoxygenase/4‐nitroso‐N,N‐dimethylaniline (LOX/RNO) method, able to simultaneously detect different antioxidant mechanisms, as well as using the Oxygen Radical Absorbance Capacity (ORAC) and the Trolox Equivalent Antioxidant Capacity (TEAC) assays, which measure the scavenging activity against peroxyl and ABTS [2,2′‐azino‐bis‐(3‐ethylbenzothiazoline‐6‐sulfonate)] radicals, respectively. The species under study were compared with respect to the sum of AA values of H, L and FSP extracts (AA_H+L+FSP), containing freely solvent‐soluble antioxidants, and AA values of IBP extracts (AA_IBP), representing the phenolic fraction ester‐linked to insoluble cell wall polymers. The LOX/RNO and ORAC methods measured in quinoa flour a remarkable AA_H+L+FSP higher than durum wheat, although lower than emmer; according to the same assays, the IBP component of quinoa resulted less active than the durum wheat and emmer ones. The TEAC protocol also revealed a high AA_H+L+FSP for quinoa. Interestingly, the ratio AA_H+L+FSP/AA_H+L+FSP+IBP, as evaluated by the LOX/RNO and ORAC assays, resulted in quinoa higher than that of both durum wheat and emmer, and much higher than durum wheat, according to the TEAC protocol. This may suggest that antioxidants from quinoa seeds may be more readily accessible with respect to that of both the examined wheat species. Practical Applications: Quinoa seeds may represent an excellent source of natural antioxidant compounds and, in particular, of the free‐soluble antioxidant fraction. These compounds may improve nutritive and health‐beneficial properties of quinoa‐based gluten‐free products, thus expanding interest for quinoa utilization from celiac patients to the general population.