Recovery of magnesium and protein from soy tofu whey by electrodialytic configurations

Electrodialysis (ED), bipolar‐membrane electro‐acidification (BMEA), and a combination of ED followed by BMEA (ED+BMEA) were evaluated for magnesium (Mg) and protein recovery and electrical energy consumption when processing soy tofu whey that was manufactured using magnesium chloride as a protein coagulant. ED processing for 30 min and BMEA processing for 60 min recovered 18.4% and 14.3% of the soy tofu whey Mg respectively. BMEA processing for 60 min recovered 22.7% of the soy tofu whey protein. The combination of ED processing for 60 min followed by BMEA for 60 min recovered 65% and 34.7% of the soy tofu whey Mg and protein, respectively. © 1999 Society of Chemical Industry     

TopoPlan: a topological path planner for real time human navigation under floor and ceiling constraints

In this article we present TopoPlan, a topological planner dedicated to real-time humanoid path-planning and motion adaptation to floor and ceiling constraints inside complex static environments. This planner analyzes unstructured 3D triangular meshes in order to automatically determine their topology. The analysis is based on a prismatic spatial subdivision which is analyzed, taking into account humanoid characteristics, in order to extract navigable surfaces and precisely identify environmental constraints such as floors, ceilings, walls, steps and bottlenecks. The technique also provides a lightweight roadmap computation covering all accessible free space. We demonstrate the properties of our topological planner within the context of two reactive motion control processes: an on-the-fly trajectory optimization and foot print generation process that correctly handles climbing of complex staircases, and a reactive ceiling adaptation process that handles beam avoidance and motion adaptation to irregular floors and ceilings. We further show that the computation cost of these processes is compatible with the real time animation of several dozens of virtual humans.     

Clarification of apple juice by electroflotation

Apple Juice industry is in search of a simplified technology which enables a quick clarification and stabilisation of apple juice. This study aimed to evaluate the potential of electroflotation as an alternative for the clarification of apple juice. Clarification of apple juice by electroflotation was first done at various current densities (10, 20 and 40 mA/cm²) with and without addition of gelatin (200 mg/l). Afterwards, the electroflotation treatments were done at a current density of 20 mA/cm² with various concentrations of added gelatin (0, 50, 100 and 200 mg/l). It was shown that electroflotation treatments alone was efficient to reduce the tannin and protein contents of apple juice. However, the decrease in the protein content was in large part due to the use of pectinases prior to the electroflotation treatments. The use of gelatin in combination with the electroflotation aided in the clarification process. The highest gelatin concentration used in this study (200 mg/l) resulted in a better reduction of tannin and protein levels, while a current density of 20 mA/cm² was found to be optimal. Turbidity observed in the juices clarified with electroflotation treatments was in average lower than 10 NTU but higher than 2 NTU which is generally required to produce a stable clarified juice. Brix degree and pH of the apple juice was not affected by the electroflotation treatments while the color was improved.

Industrial relevance

The production of clarified and stable apple juice is a subject of interest for the beverages industries. The clarification step which remained long and discontinuous implied the addition of a large quantity of pectolytic enzyme and of clarifying agents (such as gelatin) to the freshly pressed juice to induce the precipitation of proteins and other suspended matter in 15–20 h. Fining treatments were followed by a separation step usually consisting of decantation and classical filtration on filter-press, or flotation by dispersed gas. The development of membrane separation processes to replace the traditional approach has enabled the automation of the whole production resulting in lower labor requirement and a considerably shorter process time than the traditional process.However, the performance of membrane separation processes is influenced by the declining permeate flux with time, which is due to membrane fouling. In some instances, permeate flux decline makes membrane separation processes unattractive for the clarification of apple juice. To our knowledge, we are the first research group to use electroflotation (EF) for clarification of apple juice. It was shown that EF treatments alone were efficient to reduce the tannin and protein contents of apple juice. In addition, the use of gelatin in combination with the EF aided in the clarification process. Turbidity observed in the juices clarified with EF treatments for 30 min was in average lower than 10 NTU. Brix degree and pH of the apple juice were not affected by the EF treatments while the color was improved.When compared to the values reported in the literature for flotation by dispersed gas, it seems that EF shows better efficiency than flotation in decreasing the juice turbidity (99% decrease for EF as compared to 90% decrease for flotation). In addition, for experiments carried out by conventional flotation larger amount of fining agent are used (70–150 mg of gelatin/l, 400–800 mg/l of silica sol and 200–500 mg/l of bentonite). For these reasons, the new process we propose is advantageous when compared to the traditional flotation approach and it should have a measurable impact on the advancements in the production of clarified apple juice. If used as a pre-treatment to ultrafiltration clarification, it is expected that it would reduce membrane fouling resulting in higher productivity.     

Comparison between reconstituted and fresh skim milk chemical and electrochemical acidifications

The aim of this study was to compare the electrochemical and chemical acidification of reconstituted and fresh skim milk in terms of electrodialytic parameters, precipitation kinetics, chemical composition and physicochemical and functional properties of isolates produced by bipolar membrane electro acidification (BMEA). The electrodialytic parameters were not influenced by the type of milk when both milks were compared at a similar protein and salt content. The difference in precipitation kinetics observed between the two milks, whatever the acidification procedure, can be explained mainly by a difference in salt content. Isolates produced by BMEA showed similar physicochemical and functional properties (except for foaming capacity) to isolates produced chemically. The main factor affecting the composition and the physicochemical and functional properties was the pre‐treatment of milk prior to acidification: it had a higher impact on the functional properties than the acidification treatment itself. Copyright © 2002 Crown in the right of Canada. Published for SCI by John Wiley & Sons, Ltd     

Electrophysiological changes during the sleep onset period of psychophysiological insomniacs, psychiatric insomniacs, and normal sleepers

The electroencephalograms (EEGs) of the sleep onset period (SOP) of psychophysiogical insomniacs. psychiatric insomniacs, and controls were compared using power spectral analysis. We predicted that psychophysiological insomniacs would show elevated cortical arousal throughout their entry into sleep. Electroencephalograms, electrooculograms (EOGs), and electromyograms (EMGs) were recorded for two consecutive nights. Power spectral analysis of EEG from the sleep onset period was performed on all standard frequency bands. Psychophysiological insomniacs had less alpha during the first part of the SOP and did not show the dramatic drop in alpha across the SOP that characterizes normal sleep. They showed less delta in the last quartile of the chronological analysis of the SOP. Psychiatric insomniacs showed lower relative beta power values overall, while psychophysiological insomniacs showed higher relative beta power values during wakefulness. This microanalysis indicates that the SOP is generally similar for psychiatric insomniacs and normal sleepers but that clear differences in the SOP of psychophysiological insomniacs exist. They have higher cortical arousal during the SOP than do psychiatric insomniacs and controls. The dramatic changes in power values in the latter two groups as sleep begins are not seen in the psychophysiological insomniacs, which may help explain the difficulty that psychophysiological insomniacs have discriminating between wakefulness and sleep.     

Production of small high-density lipoprotein particles after stimulation of in vivo lipolysis in hypertriglyceridemic individuals: studies before and after triglyceride-lowering therapy

In hypertriglyceridemic states, triglyceride enrichment of high-density lipoprotein (HDL) may play an important role in decreasing the HDL cholesterol and apolipoprotein (apo) A-1 plasma concentration. We have shown previously that HDL particles are transformed into small HDLs when lipolysis is stimulated in vivo or in vitro, and this process is more marked if the HDL is triglyceride-rich. The present study was conducted to determine whether the susceptibility of HDL to transformation can be altered by triglyceride-lowering therapy in humans. Seventeen moderately hypertriglyceridemic individuals (nine with type II diabetes mellitus and eight moderately hypertriglyceridemic nondiabetic subjects) were studied before and after 3 months of triglyceride-lowering therapy with gemfibrozil. Since no significant differences in postprandial and postheparin HDL metabolism were detected between type II diabetic and nondiabetic subjects, results are reported for the two groups combined (N = 17). Fasting HDL was triglyceride-rich with a preponderance of HDL3, and became more enriched with triglycerides postprandially. Heparin administration resulted in a rapid decrease in plasma and HDL triglycerides and an increase in plasma and HDL free fatty acids (FFAs). Postheparin, there was a reduction in HDL size and an increase in the proportion of small (HDL3c) HDL particles (HDL3c constituted 7.1% +/- 1.8% of total HDL preheparin and 26.6% +/- 3.8% postheparin, P < .001). Triglyceride-lowering treatment resulted in a decrease in fasting triglycerides (-54%, P < .001) and HDL triglyceride content (-36%, P = .002), an increase in fasting HDL cholesterol (19%, P = .004), and proportionately fewer (13.2% +/- 2.1%, P < .001) HDL3c particles formed postheparin. Postheparin HDL size correlated inversely with the fasting triglyceride level (r = -.55, P < .001) and HDL triglyceride concentration (r = -.34, P = .02). These results show that the postprandial increase in triglyceride levels in hypertriglyceridemic subjects is associated with increased production of small HDL particles when lipolysis is stimulated, and that lipid-lowering therapy can contribute to favorably reduce this postprandial production of small HDL particles. Further studies are needed to clarify how these abnormalities ultimately lead to a decrease of plasma HDL cholesterol and apo A-1 in hypertriglyceridemic states.     

Rac and Cdc42 induce actin polymerization and G1 cell cycle progression independently of p65PAK and the JNK/SAPK MAP kinase cascade

Rac and Cdc42 regulate a variety of responses in mammalian cells including formation of lamellipodia and filopodia, activation of the JNK MAP kinase cascade, and induction of G1 cell cycle progression. Rac is also one of the downstream targets required for Ras-induced malignant transformation. Rac and Cdc42 containing a Y40C effector site substitution no longer intact with the Ser/Thr kinase p65PAK and are unable to activate the JNK MAP kinase pathway. However, they still induce cytoskeletal changes and G1 cell cycle progression. Rac containing an F37A effector site substitution, on the other hand, no longer interacts with the Ser/Thr kinase p160ROCK and is unable to induce lamellipodia or G1 progression. We conclude that Rac and Cdc42 control MAP kinase pathways and actin cytoskeleton organization independently through distinct downstream targets.     

Niveau relatif de polysémie de 50 adjectifs qualificatifs.

A number of studies have determined the ambiguity level of some personality traits, but the methods used in these studies have all been inadequate in one way or another. A new way of obtaining an index of polysemy (ambiguity) which comes from 2 measures (evaluation and association strength) is described. The polysemy of 50 qualificatory adjectives was calculated on data obtained from a group of 100 Ss. Results show that there is no correlation between the polysemy and evaluation variance of the 50 adjectives. On the other hand, it was found that the more positive an adjective is, the greater are its chances of being polysemic. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Voluminosity of some food proteins in aqueous dispersions at various pH and ionic strengths

Commercial casein and whey protein and laboratory preparation of soybean protein of various pH were dispersed in distilled water at the initial concentration of 4.0% w/v and then diluted with NaCl solutions of known ionic strengths (μ). Viscosity was measured and voluminosity (V_e=ml/g) was calculated using Lee’s equation relating volume fraction (φ_v) to relative viscosity: η/η_o=1+2.5φ_v+7.031φ²_v+37.371φ³_v. The combined effects of pH and μ on V_e were determined from regression analysis. V_e was inversely related to μ between 0.005 and 0.07 M and increased with pH between 6 and 8 and decreased at higher pH. The results are discussed in terms of the relationship between the protein electrostatic charges and structure. It is concluded that in associative proteins V_e is controlled by the number of electrostatic charges and their strength.