Stability and rheological behaviour of salad dressing obtained with whey and different combinations of stabilizers

In this work the stability and the rheological behaviour of salad dressing containing 'Minas Frescal' whey cheese was studied. The salad dressing was stabilised by xanthan gum (XG), propylene glycol alginate (PGA) and carboxymethylcellulose (CMC). All samples were stable for a period of 4 months. The rheological model of Ostwald-de-Waelle (Power-Law) was used in order to fit the data and to obtain the rheological parameters of flow behaviour index ( n ), consistency coefficient and apparent viscosity (η_ap). All formulations showed a pseudoplastic behaviour and the PGA contributed to increase the values of flow behaviour index. Consistency coefficient was similarly affected by XG and PGA fractions. Apparent viscosity was highly influenced by the hydrocolloid CMC, with higher values of apparent viscosity in the proportion of 0.25/0.25/0.5% (PGA/XG/CMC). Hydrocolloid association (ternary mixtures) was statistically significant, resulting in an increase of K and η_ap parameters. The results show that salad dressing with whey as aqueous phase and stabilised by a ternary combination of XG, PGA and CMC can be a technological alternative to the food industry.     

An evaluation of four measures of adolescents' exposure to cigarette marketing in stores.

This study evaluates four measures of exposure to retail cigarette marketing in relation to adolescent smoking behavior. The measures are (a) shopping frequency in types of stores known to carry more cigarette advertising than other store types, (b) shopping frequency in specific stores that sell cigarettes in the study community, (c) the amount of exposure to cigarette brand impressions in stores where students shopped, and (d) perceived exposure to cigarette advertising. The study combined data from classroom surveys administered to 6th-, 7th-, and 8th-grade students in three California middle schools, and direct store observations quantifying cigarette marketing materials and product placement in stores where students shopped. Logistic regression models were used to examine how each exposure measure related to the odds of ever smoking and susceptibility to smoke, controlling for grade, gender, ethnicity, school performance, unsupervised time, and exposure to household and friend smoking. Frequent exposure to retail cigarette marketing as defined by each of the four measures was independently associated with a significant increase in the odds of ever smoking. All but the measure of exposure to store types was associated with a significant increase in the odds of susceptibility to smoke. Four measures of exposure to retail cigarette marketing may serve equally well to predict adolescent smoking but may vary in cost, complexity, and meaning. Depending on the outcomes of interest, the most useful measure may be a combination of self-reported exposure to types of stores that contain cigarette marketing and perceived exposure to such messages.     

A practical method for identifying the propagation path of plant-wide disturbances

Disturbances in a continuous process often travel along the product stream and affect the performance of the process. To isolate the root cause and find the path along which the disturbance propagates requires an understanding of the cause-and-effect relationships between multiple variables. One way of identifying these relationships is through the time delays between process variables. A practical and robust approach is proposed that uses the cross-correlation function to estimate the time delay between process measurements and derives a qualitative model of the propagation path in the form of a causal map. The approach was applied to an industrial case study of a process affected by a plant-wide disturbance and was able to decide between two alternative root cause explanations. It was also applied successfully to a process with a recycle. The advantages of the proposed method are its ease of implementation and automation as well as simple interpretation of the resulting causal map.     

Neurocognitive status in long-term survivors of childhood CNS malignancies: A report from the Childhood Cancer Survivor Study.

To assess neurocognitive functioning in adult survivors of childhood Central Nervous System (CNS) malignancy, a large group of CNS malignancy survivors were compared to survivors of non-CNS malignancy and siblings without cancer on a self-report instrument (CCSS-NCQ) assessing four factors, Task Efficiency, Emotional Regulation, Organization and Memory. Additional multiple linear regressions were used to assess the contribution of demographic, illness, and treatment variables to reported neurocognitive functioning in CNS malignancy survivors and the relationship of reported neurocognitive functioning to socioeconomic indicators. Survivors of CNS malignancy reported significantly greater neurocognitive impairment on all CCSS-NCQ factors than non-CNS cancer survivors or siblings (p     

Monte Carlo simulation of the back-diffusion of electrons in nitrogen

In this paper, the process of back-diffusion in nitrogen is studied by means of Monte Carlo simulations. In particular we analyze the influence of different aspects of back-diffusion in order to simplify the models of plasma displays, low pressure gas breakdown and detectors of high energy particles. The obtained simulation results show that the escape coefficient depends strongly on the reflection coefficient and the initial energy of electrons. It was also found that the back-diffusion range and number of collisions before returning to the cathode in nitrogen are smaller than those in argon for similar conditions.     

Sonochemical deposition of silver nanoparticles on wool fibers

Silver nanoparticles were deposited on the surface of natural wool with the aid of powered ultrasound. The average particle size was 5–10 nm, but larger aggregates of 50–100 nm were also observed. The sonochemical irradiation of a slurry containing wool fibers, silver nitrate, and ammonia in an aqueous medium for 120 min under an argon atmosphere yielded a silver–wool nanocomposite. By varying the gas and reaction conditions, we could achieve control over the deposition of the metallic silver particles on the surface of the wool fibers. The resulting silver‐deposited wool samples were characterized with X‐ray diffraction, transmission electron microscopy, high‐resolution transmission electron microscopy, high‐resolution scanning electron microscopy, electron‐dispersive X‐ray analysis, Brunauer, Emmett, and Teller physical adsorption method, X‐ray photoelectron spectroscopy, and Raman and diffused reflection optical spectroscopy. The results showed that the strong adhesion of the silver to the wool was a result of the adsorption and interaction of silver with sulfur moieties related to the cysteine group. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1732–1737, 2007     

穿越活动地裂缝地铁隧道震害机制研究

 通过振动台模型试验对穿越活动地裂缝的地铁隧道的动力响应进行了研究,研究内容主要包括地铁隧道的加速度反应,土压力及应变的变化规律。分析结果表明,穿越活动地裂缝的地铁隧道在地震荷载作用中,活动地裂缝场地产生不均匀沉降,上盘沉降大于下盘区,预设地裂缝部位沉降值最大,不均匀沉降导致次生裂缝及沉降陡坎产生,地铁隧道上方场地土体产生细小裂缝;地铁隧道与活动地裂缝的加速度时程曲线均与地震动荷载加速度时程具有一致性,地铁隧道各部位加速度时程保持一致,说明在地震中地铁运动保持整体性,上盘场地的加速度峰值较大,表明在活动地裂缝中上盘区对地震动力有一定的放大效应;活动地裂缝场地中土压力呈现出动土压力曲线变化,地震加载结束后隧道结构侧向的土压力受力状态及大小均产生变化,隧道结构顶部的土压力有较大增加;应变曲线表明在扩大断面的马蹄形隧道结构中拱腰部位的应变增值最大,拱顶部位次之,底板的应变增值相比最小。以上成果对于合理认识跨越地裂缝的地铁隧道的地震响应特征具有重要意义,可为地铁隧道实际工程设计和施工的抗震设防提供宝贵的基础资料。     

Characterisation of lactic acid bacteria isolated from the Georgian,yoghurt‐like Matsoni

Matsoni is a traditional Caucasian fermented milk product, characterised by a lactic acid bacteria (LAB) microbiota. Objectives of the present study were to isolate and identify the LAB of Matsoni samples collected from various Georgian areas and to study their technological characteristics. About 300 LAB from 71 samples of Matsoni were isolated and characterised. The species most representatives were Lactobacillus delbrueckii, Streptococcus thermophilus and Lactobacillus rhamnosus. This study highlighted a high degree of biodiversity and a specific geographical distribution of the dominant LAB present in artisanal Matsoni. Some strains showed technological features useful to design a multistrain starter culture for Matsoni.