Effect of experimental conditions on the parameters used for evaluating the performance of the catalyst Mo/Al2O3 in diesel soot combustion

The literature reported different studies of soot combustion reaction under very distinct experimental conditions, which can include different values of catalyst:soot weight ratios, gas flow and heating rates. Therefore, avoiding screening of innumerable catalysts or empirical experiments, this work aims to present a general methodology based on a statistical experimental design of experiments with soot combustion, evaluating different reaction conditions and parameters that can be used for any other similar study. In this way, the effect of experimental conditions on the parameters used for evaluating the performance of Mo/Al₂O₃, a promising system previously studied, and Pt/Al₂O₃, a notorious catalytic system, were studied by a complete factorial experimental design. The results have shown that the experimental conditions strongly interfere with the parameters used for evaluating the catalytic performance and then it may generate incorrect conclusions.The effects of interaction between different conditions on the activity and mainly on the selectivity of CO₂ permitted to explain the performance of catalysts on soot combustion and to distinguish different pathways of catalytic and non-catalytic reactions under specific reaction conditions.The most appropriate conditions for studying soot combustion seem to be high cat:soot ratios, low heating rates and high gas flow rates, which, according to this work, must be equal to: 95:1, 2 K min⁻¹ and 115 mL min⁻¹, respectively.     

Deacidification of Soybean Oil by Ion Exchange

This work investigated the deacidification of soybean oil by ion exchange using a fixed bed loaded with the strong anionic resin Amberlyst A26 OH. Degummed soybean oil was dissolved in isopropanol and the deacidification process was studied according to an experimental design based on two factors, the feed flow rate and its content of free fatty acids. The responses of interest were the solute recovery efficiency and the bed utilization efficiency, both calculated from breakthrough curves. Oil samples before and after deacidification by ion exchange, as well as samples deacidified in the industrial plant by the chemical method, were characterized according to the usual indexes for quality and identity. The results revealed that the flow rate was an important and statistically significant factor with 95 % of confidence. The deacidification by ion exchange decreased the oil acidity and also removed undesirable compounds, such as phospholipids and peroxides. However, a decrease in the concentration of tocopherol was also observed.     

Quantification and Determination of Composition of Steryl Ferulates in Refined Rice Bran Oils Using an UPLC-MS Method

Gamma-oryzanol contains a mixture of steryl ferulates found in rice bran oil. Several studies have attributed nutraceutical properties to this mixture, such as hypocholesterolemic and anti-inflammatory activities. A method based on ultra-performance liquid chromatography coupled with electrospray ionization mass spectrometry was developed and evaluated for the simultaneous quantification of gamma-oryzanol and identification of five major steryl ferulates directly in refined rice bran oils (RBO) samples. The proposed method was evaluated according to linearity by obtaining standard curves with R ² values above 0.990, and limit of detection values ranged from 1.9 to 5.9 µg/mL, whereas limits of quantification ranged from 5.9 to 17.9 µg/mL; inter- and intraday accuracy and precision were within the range required by the US Food and Drug Administration guidelines; recovery levels ranged from 78 to 85% for gamma-oryzanol, and from 84 to 119% for steryl ferulates. The method can be considered robust in relation to the NH₄OH (ammonium hydroxide) content and cone voltage variations, with coefficient of variation and average relative percentage deviation values lower than 7.0 and 4.4%, respectively. The stability during the storage test was maintained in concentrated samples (18.5 µg/mL), with recovered values between 93 and 113%. This method was successfully applied to the analysis of RBO samples, demonstrating that it could be easily used for quality control purposes.     

Milk with different somatic cells counts and the physicochemical,microbiological characteristics and fatty acid profile of pasteurised milk cream: is there an association?

In this study, raw cow milk containing somatic cells counts (SCC) at mean levels of 39 000 cells mL^?1 (low), 349 000 cells mL^?1 (intermediate) and 1 297 000 cells mL^?1 (high) was used for the production of pasteurised cream. Physicochemical (pH, fat and fatty acid profile) and microbiological analyses (mesophilic and psychrotrophs) were performed in the obtained creams during 30 days of refrigerated storage at 5 °C ± 2. No interactions (P > 0.05) were found between SCC, storage time and the physicochemical and microbiological variables studied. Fatty acid profile was similar among the SCC creams, except for oleic acid (C18:1), which decreased (P < 0.05) in intermediate and high SCC creams. Considering the technological aspect, our findings suggest that milk cream manufacture can be an interesting option for the use of high SCC milk.     

Using a Strong Anion-Exchange Resin to Deacidify Red Palm Oil

This work aims to evaluate the use of an alternative process to deacidify palm oil using a strong anion-exchange resin (Amberlyst A26 OH). The effects of the feed flow rate and the free fatty acids content in the feed stream were investigated by measuring breakthrough curves for bleached palm oil dissolved in n-propanol. The resin had sufficient capacity and affinity to remove palmitic and oleic acids (98–99 %). The bed utilization efficiency can be optimized by choosing lower flow rates for oils with low levels of acidity, while higher flow rates can be used for oils with higher free fatty acids content. The ion-exchange process can be used to obtain deacidified red palm oil, while preserving carotenoid and tocopherol/tocotrienol content. This alternative process has the advantage of occurring under mild conditions (44.0 ± 0.8 °C and atmospheric pressure) when compared with the conditions used in molecular distillation (150.0–170.0 °C and 2.7–3.3 Pa).     

The privatization of EEB: From cash drain to major contributor

In this paper we describe the successful part-privatization of Empresa de Energia de Bogotá (EEB), the city-owned electricity company in Bogotá, Colombia. We describe the reason, the preparation and the actual sale process as well as the outcome following the part-privatization. EEB went from being a company on the edge of bankruptcy to one of the most financially secure electricity companies in South America. We also place the case in relation to the standard views on direct foreign investment and their social benefit. Finally, we aim to generalize the experience to see what other organizations in a similar position can learn.     

Military youth and the deployment cycle: Emotional health consequences and recommendations for intervention.

The United States military force includes over 2.2 million volunteer service members. Three out of five service members who are deployed or are preparing for deployment have spouses and/or children. Stressors associated with the deployment cycle can lead to depression, anxiety, and behavior problems in children, as well as psychological distress in the military spouse. Further, the emotional and behavioral health of family members can affect the psychological functioning of the military service member during the deployment and reintegration periods. Despite widespread acknowledgment of the need for emotional and behavioral health services for youth from military families, many professionals in a position to serve them struggle with how to best respond and select appropriate interventions. The purpose of this paper is to provide an empirically based and theoretically informed review to guide service provision and the development of evidence based treatments for military youth in particular. This review includes an overview of stressors associated with the deployment cycle, emotional and behavioral health consequences of deployment on youth and their caretaking parent, and existing preventative and treatment services for youth from military families. It concludes with treatment recommendations for older children and adolescents experiencing emotional and behavioral health symptoms associated with the deployment cycle. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Uterine Fibroids Causing Preterm Birth: A New Pathophysiological Hypothesis on the Role of Fibroid Necrosis and Inflammation

According to recent studies and observations in clinical practice, uterine fibroids increase the risk of preterm birth. There are several theories on the pathogenesis of preterm birth in the presence of fibroids. One theory proclaims that fibroid necrosis leads to preterm birth, though pathophysiological mechanisms have not been described. Necrotic tissue secretes specific cytokines and proteins and we suggest these to be comparable to the inflammatory response leading to spontaneous preterm birth. We hypothesize that fibroid necrosis could induce preterm parturition through a similar inflammatory response. This new hypothesis generates novel perspectives for future research and the development of preventative strategies for preterm birth. Moreover, we emphasize the importance of the recognition of fibroids and especially fibroid necrosis by clinicians during pregnancy.     

Specific peptides identified by mass spectrometry in placental tissue from pregnancies complicated by early onset preeclampsia attained by laser capture dissection

Preeclampsia is a common pregnancy‐specific syndrome that is diagnosed by the appearance of both increased blood pressure and proteinuria. Preeclampsia is associated with significant fetal and maternal morbidity and mortality. Although the etiology of preeclampsia is unknown, it is evident that abnormal placentation and trophoblast metabolism plays an important role. We therefore analyzed, identified, and verified specific proteins of villous trophoblast and villous stroma in small numbers of microdissected cells (approximately 125 cells) from seven placentas of women with pregnancies complicated by preeclampsia (cases) and seven uncomplicated pregnancies (controls). Tryptic peptide profiling by MALDI‐TOF MS was used for comparison and identification of significantly expressed peptides. The data were analyzed by ClinProTools (Bruker Daltonics) and by principal component analysis. Subsequently, a subset of placental tissues were homogenized and separated on a NanoLC system to obtain sequencing information (MS/MS spectra). We identified specific peptide patterns in the different cell types: villous stroma and trophoblast cells and differences in these cells of placentas from women with pregnancies complicated by early compared to late onset preeclampsia (<34 and >34 wk gestation, respectively) and controls. Principal component analysis revealed significant differences between the groups. The comparison with placental tissue after preterm delivery with unknown cause revealed that placental peptide patterns in early onset preeclampsia could not be explained by preterm delivery per se. Subsequently, specific, discriminating proteins for early onset preeclampsia compared to controls were identified including calcyclin, surfeit locus protein, and choriomammotropin A precursor. The expression of calcyclin was verified in early onset preeclamptic placental sections by immunohistochemistry. These data suggest that in early onset preeclampsia trophoblastic choriomammotropin regulation is abnormal, possibly through abnormal calcyclin expression and regulation.