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ROS
Kinds of ROS Terms modified by ROS Selected AbstractsDesign of dual-purpose membrane desalination systemsENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 3 2010Rajindar Singh Abstract Reverse osmosis (RO) and nanofiltration (NF) membrane plants are used extensively for brackish water desalination and industrial water purification. The operating range of RO plants is 60,80% product water recovery depending on the quality of raw water and feed water pretreatment. Typically, these plants operate at 75% recovery. The disposal of RO reject streams (20,40% of plant feed water) containing high concentration of salts is becoming an environmental problem. To reduce brine disposal costs and to increase product water recovery, several high-recovery energy-efficient membrane processes were analyzed. Generally speaking, a balance is required between brine volume reduction, capital and operating costs, energy consumption, and process simplicity. The analyses showed that up to 90% product water recovery can be achieved for low to medium brackish feed waters using RO/NF membrane systems with minimal feed water chemical pretreatment. The benefits of hybrid membrane systems integrated with fuel cell alternate energy systems are discussed. © 2009 American Institute of Chemical Engineers Environ Prog, 2010 [source] Endocrine responses of Fundulus heteroclitus to effluent from a bleached-kraft pulp mill before and after installation of reverse osmosis treatment of a waste streamENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2000Monique G. Dubé Abstract Implementation of process changes on the nonbleaching side of bleached kraft pulp mill (BKPM) operations has increased in recent years to maximize resource use and to minimize residual environmental effects of discharged effluents. The objective of this study was to determine if reverse osmosis (RO) treatment of evaporator and digester clean condensates reduced or removed the effects of a BKPM effluent on reproductive endocrine function of the estuarine killifish, Fundulus heteroclitus (mummichog). Comparison of data collected before (1997) and after (1998), the years of the process change, showed that the potential of the combined mill effluent to depress plasma testosterone levels after 30 and 57 d of exposure to an environmentally relevant effluent concentration (1%) was reduced after RO treatment of condensates. However, in vitro production of some sex steroids was depressed with a 1% effluent exposure after the process change. In addition, in 1998, depression of plasma testosterone levels in effluent-exposed fish was present at higher effluent concentrations (5%). These results are significant because they suggest that condensates may be a source of endocrine-disrupting compounds in BKPM effluents and RO may reduce their discharge. [source] Dietary intake of differently fed salmon: a preliminary study on contaminantsEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 3 2006C. Bethune Abstract Background, In a previous study, a group of coronary heart disease (CHD) patients exhibited positive cardioprotective effects of fatty acids derived from a diet of farmed Atlantic salmon fed fish oil (Seierstad et al. 2005). This follow-up study examines these patients for plasma exposure to selected organic and inorganic contaminants found in seafood that may detract from the benefits of eating oily fish. Methods, The study design was from Seierstad et al. (2005), where 58 patients were allocated into three groups consuming 700 g week,1 of differently fed Atlantic salmon (Salmo salar) fillets for 6 weeks: 100% fish oil (FO), 100% rapeseed oil (RO), or 50% of each (FO/RO). Results, Different fillets showed graded levels (FO > FO/RO > RO) of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (DLPCBs), indicator PCBs, polybrominated diphenyl ethers (PBDEs), and arsenic (As). Mercury (Hg) and lead (Pb) levels were similar across the three types of fillets. After 6 weeks of consumption, patient levels of PCDDs, DLPCBs, and PCBs in plasma decreased as the dietary intake of these contaminants increased. Plasma PBDEs only showed increases for the FO patients. Levels of inorganic contaminants in plasma showed only slight changes over the study period. Conclusions, These results show a reduction in the use of marine oils in fish feed reduces organic contaminant levels in farmed salmon while still providing a good dietary source of marine fatty acids. [source] Carboxy Ester Hydrolysis Promoted by a Dicopper(II) Macrocyclic Polyamine Complex with Hydroxypropyl Pendant GroupsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 9 2004Jin Huang Abstract A dinuclear CuII complex containing a hexaaza macrocyclic ligand bearing two 2-hydroxypropyl pendants, 3,6,9,16,19,22-hexaaza-6,19-bis(2-hydroxypropyl)tricyclo[22.2.2.211,14]triaconta-1,11,13,24,27,29-hexaene (L), was synthesized. The title complex [Cu2(H,2L)Cl2]·6.5H2O was isolated as a blue crystal, orthorhombic, space group Fddd, with a = 16.4581(12), b = 32.248(2), c = 35.830(2) Å, V = 19017(2) Å3, Z = 16, R1 = 0.0690, and wR2 = 0.1546 [I > 2,(I)]. The protonation constants of Cu2L were determined by potentiometric titration, and it was found that the alcoholic hydroxypropyl group of the complex Cu2L exhibits low pKa values of pKa1 = 7.31, pKa2 = 7.83 at 25 °C. The hydrolysis kinetics of 4-nitrophenyl acetate (NA) promoted by the title complex have also been studied. The pH-rate profile for Cu2L gave a sigmoidal curve and showed a second-order rate constant of 0.39 ± 0.02 M,1 s,1 in 10% CH3CN/H2O(v/v), which is greater than that of the dinuclear CuII complex formed by a hexaaza macrocycle without pendants. The reason for the higher catalytic activity of the title complex is discussed. We found that the volume of nucleophile RO, can effect the hydrolysis of the carboxy ester, the nucleophilicity of RO, and the Lewis acidity of the metal macrocycle also affect the carboxy ester hydrolysis. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Sodiated ,-Diphosphonate Carbanions: Characterization of the Tetrameric Cubane and the Hexameric Ladder Complexes [{(iPrO)2P(O)}2CHNa]4 and [{(EtO)2P(O)}2CHNa]6EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 18 2003Roger Nassar Abstract Reaction of the methylene diphosphonates [(RO)2P(O)]2CH2, where R = iPr or Et, with the metalating reagents NaH, nBuNa or the superbasic mixture tBuONa/nBuLi leads to monodeprotonation, and formation of the complexes [{(iPrO)2P(O)}2CHNa]4 (1) and [{(EtO)2P(O)}2CHNa]6 (2). Single-crystal X-ray diffraction studies revealed that 1 is tetrameric in the solid state, with a central Na4O4 cubane core. Each metal in 1 is rendered pentacoordinate by binding to three ,3 -O phosphoryl bridges within the cubane, a chelating phosphoryl unit, and also a single iPrO group. In contrast, the structure of 2 is hexameric, and is composed of an unusual six-rung Na6O6 ladder core. Three distinct sodium environments as well as ,1 -, ,2 - and ,3 -O phosphoryl units are present within the ladder framework. No Na,C interactions are present in either 1 or 2. All of the six-membered NaOPCPO chelate rings display localized P=O double bonds and partial multiple bonding on the P,C,P linkages (mean P,O: 1.49 Å, and mean P,C: 1.69 Å). Ab initio molecular orbital calculations (HF/6,31G*) on model complexes indicate that the hexameric arrangement found for 2 is thermodynamically more stable than the cubane structure of 1, in the absence of steric effects. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Calorimetric study of milk fat/rapeseed oil blends and their interesterification productsEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 4 2009Mario Aguedo Abstract Milk fat (MF) and rapeseed oil (RO) blends were analyzed by differential scanning calorimetry (DSC). It was shown that peak and onset temperatures can be used to determine the percentage of each fat in the blend and that the relative enthalpy of one peak assigned to low-melting triacylglycerols (TAG) can also be used to determine the percentage of RO in the blend. A linear relation was also established between MF content of the blend and its dropping point (DP), indicating that DP can be linearly related with the above DSC data. A blend of MF/RO 70,:,30 (wt/wt) was then chosen as a model system for enzymatic interesterification (EIE). The applicability of DSC analyses to EIE products was checked and a correct correlation could be established between DSC values and the interesterification degree and DP. Among the data from the DSC profiles, the peak associated with low-melting TAG was the best indicator of the reaction course. In the same way, a high-melting MF stearin fraction was interesterified with RO. In that case, onset temperatures and peak "a" were better reaction indicators than for the interesterified MF/RO blend. We therefore suggest that values from DSC endotherms could be used to monitor EIE of fat blends. [source] Less-oxidative hemodialysis solution rendered by cathode-side application of electrolyzed waterHEMODIALYSIS INTERNATIONAL, Issue 3 2007Masaaki NAKAYAMA Abstract Electrolyzed water (EW) generated on the cathode side reportedly displays anti-oxidative properties, and application of EW to hemodialysis (HD) systems supposedly suppresses oxidative markers in patients on HD. However, most of the chemical properties and biological effects of such solutions remain unclear. This study aimed to examine those issues to clarify the scientific background for the clinical use of EW solution. Reverse osmosis water comprising EW from the cathode side (e-RO) was prepared and used to process a test HD solution (e-HD). Chemical and biological properties of these solutions were compared with controls. Redox properties were examined by chemiluminescence (CL) of the luminol-H2O2 system. Biological effects of e-RO on human polymorphonuclear leukocytes (PMNs) were tested with respect to the cellular protection against methylglyoxal, and with respect to the preservation of cellular function as to radical generation. Control HD solution presented the highest CL, followed by e-HD, control RO, suggesting a lower oxidative capacity for EW-based solutions. Increased levels of dissolved hydrogen were characteristic of e-RO and e-HD. Application of e-RO tended to be associated with less injury of PMNs by methylglyoxal, and with significantly higher levels of radical generation compared with the control. Compared with control HD, e-RO-based HD solution displays less-oxidative capacity in chemical terms, and may at least partly facilitate preservation of PMN viability. These results appear to offer a scientific basis for supporting the clinical challenge of applying this technology to HD treatment. [source] The design and synthesis of ,-trifluoromethylenol phosphates as potential insecticidesHETEROATOM CHEMISTRY, Issue 4 2003Yixiang Ding A new group of compounds, ,-trifluoromethylenol phosphates [(RO)2P(O)OCRCHCF3], has been designed and prepared by several methods. Some of them showed good insecticidal activities. In the molecular structure, the designed leaving group can rearrange to a powerful electrophilic agent, ,,,-difluorovinyl ketone, which would be a potential enzyme inhibitor. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:304,308, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10147 [source] Kinetics of propane oxydehydrogenation on metals oxides and metals phosphates catalysts: Evidence of compensation effectsINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 3 2006B. Y. Jibril Kinetics of oxidative dehydrogenation of propane has been tested on three groups of catalysts; alumina-supported metal oxides (MO) (where metal is V, Cr, Ni, Zr, Mo, or Ba), alumina-supported rare earth metal oxides (RO) (where metal is Ce, Tb, Dy, Ho, Tm, or Yb), and metal phosphates (MP) (where metal is V, Cr, Mn, Ni, Zr, Mg, Ba, or Ce). They were found to be active and exhibited different selectivities to propylene, ethylene, and COx (CO and CO2). The Arrhenius parameters,apparent pre-exponential factor (lnAapp) and activation energy Eapp),were evaluated. Evidence of compensation effects was established through statistically significant linear relationship between ln Aapp and Eapp. The rates of propane conversions and COx productions on MO and MP showed common compensation line different from that of RO. When the data for rates of production of propylene and ethylene were plotted, the line for the ethylene rate on MO appeared above that of propylene rate, contrary to the observation on MP and RO. An attempt was made to associate the differences in the behaviors of the catalysts with differences in the ensembles of chemisorbed species that form the respective active centers. © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 38: 176,183, 2006 [source] Isomeric hexyl-ketohydroperoxides formed by reactions of hexoxy and hexylperoxy radicals in oxygenINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 8 2003François Jorand Isomerization reactions of peroxy radicals during oxidation of long-chain hydrocarbons yield hydroperoxides, and therefore play an important role in combustion and atmospheric chemistry, because of their action as branching agents in these chain reaction processes. Different formation mechanisms and structures are involved. Three isomeric hexyl-ketohydroperoxides are formed via isomerization reactions in oxygen of either hexoxy RO or hexylperoxy RO2 radicals. In the temperature range 373,473 K, 2-hexoxy (C6H13O) radical in O2/N2 mixtures gives 2-hexanone-5-hydroperoxide via two consecutive isomerizations. The second one is a H transfer from a HC(OH) group occurring via a seven-membered ring intermediate: Its rate constant has been determined at 453 and 483 K, and the general expression can be written as Hexylperoxy C6H13O2 radical, present in n -hexane oxidation by oxygen/nitrogen mixtures in the temperature range 543,573 K, gives 2-hexanone-4-hydroperoxide, 3-hexanone-5-hydroperoxide, and 2-hexanone-5-hydroperoxide. The first two are formed through an isomerization reaction via a six-membered ring intermediate, and the last through an isomerization reaction via a seven-membered ring intermediate. The ratio of the rate constant of the isomerization reactions of RO2 radicals via a seven-membered ring intermediate to that via a six-membered ring is found to be 0.795, and the rate constant expression via a seven-membered ring intermediate is proposed: The role of these reactions in the formation of radicals in the troposphere is discussed. Other products arising in the reactional path, such as ketones, furans, and diketones, are identified. Identification of these ketohydroperoxides was made using gas chromatography/mass spectrometry with electron impact, and with NH3 (or ND3) chemical ionization. © 2003 Wiley Periodicals, Inc. Int J Chem Kinet 35: 354,366, 2003 [source] Substitution- and Elimination-Free Phosphorylation of Functionalized Alcohols Catalyzed by Oxidomolybdenum TetrachlorideADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 1 2010Cheng-Yuan Liu Abstract Among 14 oxidometallic species examined for catalytic phosphorylation of the tested alcohols, oxidomolybdenum tetrachloride (MoOCl4) was found to be the most efficient with a negligible background reaction mediated by triethylamine (Et3N). The new catalytic protocol can be applied to the chemoselective phosphorylations of primary, secondary and tertiary alcohols as well as the substitution-free phosphorylations of allylic, propargylic, and benzylic alcohols. Functionalized alcohols bearing acetonide, tetrahydropyranyl ether, tert -butyldimethylsilyl ether, or ester group are also amenable to the new catalytic protocol. The most difficult scenarios involve substitution-free phosphorylations of 1-phenylethanol and 1-(2-naphthyl)ethanol which can be effected in 95 and 90% yields, respectively. ESI-MS, IR, 1H, and 31P,NMR spectroscopic analyses of the reaction progress suggest the intermediacy of an alkoxyoxidomolybdenum trichloride-triethylamine adduct such as [(RO)Mo(O)Cl3 -Et3N] to be responsible for the catalytic turnover. [source] Optimization of the reaction parameters of epoxidation of rapeseed oil with peracetic acidJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 8 2010Eugeniusz Milchert Abstract BACKGROUND: The epoxidation of vegetable oils has been a subject of interest for many years; epoxidized oils are frequently used as plasticizers and as renewable materials for the manufacture of alcohols, glycols and many other complex compounds with excellent antioxidant and antifriction properties. In this work the epoxidation process of rapeseed oil (RO) with peracetic acid generated in situ by the reaction of 30 wt% hydrogen peroxide and acetic acid has been studied. Optimization studies were performed by application of a statistical experimental design method utilizing a rotatable-uniform design. RESULTS: The significant parameters for the RO epoxidation process were established as temperature, molar ratio of hydrogen peroxide to rapeseed oil, molar ratio of acetic acid to rapeseed oil and reaction time. The process description was based on five response functions: iodine number, epoxy number, conversion, yield and selectivity. The highest values of all functions with the exception of selectivity were achieved for the same values of parameters: temperature 65 °C, molar ratio of hydrogen peroxide to RO 11.1:1 mol mol,1, molar ratio of acetic acid to RO 1.89:1 mol mol,1 and reaction time 6 h. CONCLUSION: In summary, these optimum parameters allow one to obtain epoxidized rapeseed oil with a yield of 66.2 mol% at an oil conversion of 91.0 mol% in mild and relatively safe conditions. The epoxy number of the product was 0.207 mol per 100 g, whereas the iodine number was 0.027 mol per 100 g. Copyright © 2010 Society of Chemical Industry [source] The growth,mortality relationship in larval cohorts of Sardinops melanostictus, revealed by using two new approaches to analyse longitudinal data from otolithsJOURNAL OF FISH BIOLOGY, Issue 7 2008G. Plaza The growth,mortality relationship was assessed for larval cohorts of the Japanese sardine Sardinops melanostictus using two new approaches: (1) repeat measures in general linear model (RM-GLMs) and (2) the autoregressive-individual method (AIM). Both methods were compared to the traditional approach in which repeat-measure ANOVA was used to compare the changes in increment width (WI) at age and otolith radii (RO) at age between individuals from an original population and survivors. In RM-GLMs, both the WI at age and RO at age (i.e. at 5, 10, 15 and 20 days) were used as the dependent variables, and the standardized residuals of both regressions RO and age and RO and total length (LT), age class, and day of the year as independent variables. A significant increase in WI at age and RO at age from younger to older age classes was seen as indicative of growth-dependent selection. In AIM, the RO -at-age relationship for each fish was fitted for the first 20 days, using autoregression, and then the growth traits (i.e. slopes) between the original cohorts and survivors were compared using ANOVA. In the traditional approach, the WI at age and RO at age for the first 20 days of an original population were compared with those of survivors sampled in later stages. GLMs and traditional approaches supported the growth rate (i.e. the faster an individual grows, the higher its probability of survival) and bigger is better (i.e. larger individuals at any given age will have lower probability of mortality than smaller individuals of the same age) mechanisms. Furthermore, AIM showed that individuals from original cohorts had lower otolith growth rates than those from survivors, giving further support for the growth,mortality hypothesis for the larval stage of this clupeid. [source] Patients' preference for radiotherapy fractionation schedule in the palliation of symptomatic unresectable lung cancer,JOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 5 2008JI Tang Summary The palliative radiotherapeutic management of unresectable non-small-cell lung cancer is controversial, with various fractionation (Fx) schedules available. We aimed to determine patient's choice of Fx schedule after involvement in a decision-making process using a decision board. A decision board outlining the various advantages and disadvantages apparent in the Medical Research Council study of Fx schedules (17 Gy in two fractions vs 39 Gy in 13 fractions) was discussed with patients who met Medical Research Council eligibility criteria. Patients were then asked to indicate their preferred Fx schedules, reasons and their level of satisfaction with being involved in the decision-making process. Radiation oncologists (RO) could prescribe radiotherapy schedules irrespective of patients' preferences. Of 92 patients enrolled, 55% chose the longer schedule. English-speaking patients were significantly more likely to choose the longer schedule (P = 0.02, 95% confidence interval: 1.2,7.6). Longer Fx was chosen because of longer survival (90%) and better local control (12%). Shorter Fx was chosen for shorter overall treatment duration (80%), cost (61%) and better symptom control (20%). In all, 56% of patients choosing the shorter schedule had their treatment altered by the treating RO, whereas only 4% of patients choosing longer Fx had their treatment altered (P < 0.001). Despite this, all (100%) patients were satisfied with being involved in the decision-making process. The decision board was useful in aiding decision-making, with both Fx schedules being acceptable to patients. Interestingly, despite the longer average survival associated with longer Fx, nearly half of the patients believed that this was not as important as a shorter duration of treatment and lower cost. Despite patients' preferences, there were significant alterations of preferred schedules because of RO's own biases. [source] Tezosentan normalizes hepatomesenteric perfusion in a porcine model of cardiac tamponadeACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2009A. ÅNEMAN Background: To investigate endothelin-1 (ET-1)-dependent hepatic and mesenteric vasoconstriction, and oxygen and lactate fluxes in an acute, fixed low cardiac output (CO) state. Methods: Sixteen anesthetized, mechanically ventilated pigs were studied. Cardiac tamponade was established to reduce portal venous blood flow (QPV) to 2/3 of the baseline value. CO, hepatic artery blood flow (QHA), QPV, hepatic laser-Doppler flow (LDF), hepatic venous and portal pressure, and hepatic and mesenteric oxygen and lactate fluxes were measured. Hepatic arterial (RHA), portal (RHP) and mesenteric (Rmes) vascular resistances were calculated. The combined ETA,ETB receptor antagonist tezosentan (RO 61-0612) or normal saline vehicle was infused in the low CO state. Measurements were made at baseline, after 30, 60, 90 min of tamponade, and 30, 60, 90 min following the infusion of tesozentan at 1 mg/kg/h. Results: Tamponade decreased CO, QPV, QHA, LDF, hepatic and mesenteric oxygen delivery, while hepatic and mesenteric oxygen extraction and lactate release increased. RHA, RHP and Rmes all increased. Ninety minutes after tesozentan, QPV, LDF and hepatic and mesenteric oxygen delivery and extraction increased approaching baseline values, but no effect was seen on CO or QHA. Hepatic and mesenteric handling of lactate converted to extraction. RHA, RHP and Rmes returned to baseline values. No changes were observed in these variables among control animals not receiving tesozentan. Conclusion: In a porcine model of acute splanchnic hypoperfusion, unselective ET-1 blockade restored hepatomesenteric perfusion and reversed lactate metabolism. These observations might be relevant when considering liver protection in low CO states. [source] Efficacy of rabeprazole on heartburn symptom resolution in patients with non-erosive and erosive gastro-oesophageal reflux disease: a multicenter study from JapanALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 1 2007H. MIWA Summary Background, Few studies have compared the efficacy of proton pump inhibitors in resolving the symptoms of non-erosive reflux disease (NERD) and of erosive gastro-oesophageal reflux disease (GERD) in Japan. Aim, To investigate and compare the efficacy of 4-week course of rabeprazole 10 mg/day on symptom resolution in NERD and erosive GERD in Japan. Methods, The modified Los Angeles classification was used to grade endoscopically GERD in patients with heartburn (Grades N and M: NERD, Grades A and B: mild reflux oesophagitis (RO), and Grades C and D: severe RO). Rabeprazole 10 mg/day was administered for 4 weeks to 180 patients who kept symptom diaries. Results, Complete relief of the symptoms was achieved in 35.8% of the NERD group and 55.4% of the erosive GERD group (mild RO: 51.1% and severe RO: 77.8%). Rabeprazole was significantly more effective in erosive GERD than in NERD patients. Among the NERD subgroups (Grades N and M), no difference in symptom improvement was observed. Conclusions, Four-week, rabeprazole 10 mg/day acid suppression therapy was effective in resolving symptoms in Japanese GERD patients. This therapy was more effective in erosive GERD than in NERD patients, and in those with severe RO than in those with mild RO. [source] Protostellar discs formed from rigidly rotating coresMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2009S. Walch ABSTRACT We use three-dimensional smoothed particle hydrodynamic simulations to investigate the collapse of low-mass pre-stellar cores and the formation and early evolution of protostellar discs. The initial conditions are slightly supercritical Bonnor,Ebert spheres in rigid rotation. The core mass and initial radius are held fixed at MO= 6.1 M, and RO= 17 000 au, and the only parameter that we vary is the initial angular speed ,O. Protostellar discs forming from cores with ,O < 1.35 × 10,13 s,1 have radii between 100 and 300 au and are quite centrally concentrated; due to heating by gas infall on to the disc and accretion on to the central object, they are also quite warm, , and therefore stable against gravitational fragmentation. In contrast, more rapidly rotating cores form discs which are less concentrated and cooler, and have radii between 400 and 1000 au; as a consequence they are prone to gravitational fragmentation and the formation of multiple systems. We derive a criterion that predicts whether a rigidly rotating core having given MO, RO and ,O will produce a protostellar disc which fragments whilst material is still infalling from the core envelope. We then apply this criterion to core samples for which MO, RO and ,O have been estimated observationally. We conclude that the observed cores are stable against fragmentation at this stage, due to their low angular speeds and the heat delivered at the accretion shock where the infalling material hits the disc. [source] Nano-reactors for controlling the selectivity of the free radical grafting of maleic anhydride onto polypropylene in the meltPOLYMER ENGINEERING & SCIENCE, Issue 10 2006Dean Shi This paper reports on a successful application of the concept of nanoreactors to effectively controlling the selectivity of the free radical grafting of maleic anhydride (MAH) onto polypropylene (PP) in the melt, an industrially relevant process. More specifically, a free radical initiator of type ROOR was first confined into (or encapsulated by) the galleries of an organically modified montmorillonite (o-MMT) whose interdistance was 2.4 nm. Primary free radicals (RO ·) formed inside the o-MMT galleries had to diffuse out before they could react with the PP backbone. The controlled release of the primary free radicals significantly increased the grafting degree of MAH onto PP and greatly reduced the level of the chain scission of the latter. Those results were better understood by electron spin resonance studies on model systems and by Monte Carlo simulations. POLYM. ENG. SCI. 46:1443,1454, 2006. © 2006 Society of Plastics Engineers. [source] Initial Deposition of Colloidal Particles on a Rough Nanofiltration MembraneTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 5 2007Tania Rizwan Abstract The initial rate of colloid deposition onto semi-permeable membranes is largely controlled by the coupled influence of permeation drag and particle-membrane colloidal interactions. Recent studies show that the particle-membrane interactions are subject to immense local variations due to the inherent morphological heterogeneity (roughness) of reverse osmosis (RO) and nanofiltration (NF) membranes. This experimental investigation reports the effect of membrane roughness on the initial deposition of polystyrene latex particles on a rough NF membrane during cross flow membrane filtration under different operating pressures and solution chemistries. Atomic force microscopy was used to characterize the roughness of the membrane and observe the structure of particle deposits. At the initial stages of fouling, the AFM images show that more particles preferentially accumulate near the "peaks" than in the "valleys" of the rough NF membrane surface. Le taux initial de la déposition colloïdale sur des membranes semi-perméables est largement contrôlé par l'influence couplée entre la traînée de perméation et les interactions colloïdales membrane-particules. Des études récentes montrent que les interactions membranes-particules sont sujettes à d'immenses variations locales en raison de l'hétérogénéité morphologique inhérente (rugosité) des membranes d'osmose inverse (RO) et de nanofiltration (NF). Cette étude expérimentale décrit l'effet de la rugosité des membranes sur la déposition initiale de particules de latex de polystyrène sur une membrane NF rugueuse lors de la filtration des membranes en écoulement transversal pour différentes conditions opératoires et compositions chimiques des solutions. On a eu recours à la microscopie à force atomique pour caractériser la rugosité de la membrane et observer la structure des dépôts de particules. Aux stades initiaux du refoulement, les images AFM montrent que les particules s'accumulent préférentiellement près des «pics» plutôt que dans les «vallées» de la surface de membrane NF rugueuse. [source] Financial Champions and Masters of Innovation: Analyzing the Effects of Balancing Strategic Orientations,THE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 6 2009Angela Paladino Theory predicts that market and resource orientations can each lead to innovation and financial success. Despite this, no research has examined whether the pursuit of both resource and market orientations is feasible and, if so, the impact of this combined effect on innovative and financial outcomes. This paper aims to address these gaps. Thus, it is the first to examine the interdependent relationship between market orientation (MO) and resource orientation (RO). Additionally, this study responds to calls for (1) cross-disciplinary research, particularly in the areas of marketing and strategic management, and (2) comparative studies of diverse strategic orientations on performance. In doing so, this paper investigates the difference in innovation performance and financial performance between firms adopting a high or low degree of market orientation or a high or low degree of resource orientation. This allows us to observe independent and interdependent effects of these orientations on the firm's performance. Data were collected from 250 senior executives in Australia. Confirmatory factor analysis and related techniques were applied to assess the robustness of the measures used. A two-way between-groups analysis of variance (ANOVA) was used to evaluate the relationships. Results show the emergence of four organizational types: unfocused imitators or followers; market-driven innovators; masters of innovation; and financial champions. From these, financial champions emerge as having the greatest impact on the financial performance of the firm, while masters of innovation are best for maximizing innovation outcomes. In fact, organizations with a high RO in the matrix (masters of innovation and financial champions) achieved a higher impact on innovation relative to the quadrants reflecting a lower MO. Results also demonstrate that pursuing a low degree of resource and market orientations leads to inferior financial performance. Therefore, a balance of resource and market orientations is important. A potential extension of this research is to assess these relationships on an industry-by-industry basis. This would contribute to our knowledge by allowing us to determine if and how these results differ between industries. Managerial and theoretical implications are also discussed. [source] Demographic and Psychosocial Features of Participants in Bondage and Discipline, "Sadomasochism" or Dominance and Submission (BDSM): Data from a National SurveyTHE JOURNAL OF SEXUAL MEDICINE, Issue 7 2008Juliet Richters ABSTRACT Introduction., People with sexual interests in bondage and discipline, "sadomasochism" or dominance and submission (BDSM) have been seen by many professionals as damaged or dangerous. Aim., To examine sexual behavior correlates of involvement in BDSM and test the hypothesis that BDSM is practiced by people with a history of sexual coercion, sexual difficulties, and/or psychological problems. Methods., In Australia in 2001,2002, a representative sample of 19,307 respondents aged 16,59 years was interviewed by telephone. Weighted data analysis used univariate logistic regression. Main Outcome Measures., Self-reported demographic and psychosocial factors; sexual behavior and identity; sexual difficulties. Results., In total, 1.8% of sexually active people (2.2% of men, 1.3% of women) said they had been involved in BDSM in the previous year. This was more common among gay/lesbian and bisexual people. People who had engaged in BDSM were more likely to have experienced oral sex and/or anal sex, to have had more than one partner in the past year, to have had sex with someone other than their regular partner, and to have: taken part in phone sex, visited an Internet sex site, viewed an X-rated (pornographic) film or video, used a sex toy, had group sex, or taken part in manual stimulation of the anus, fisting or rimming. However, they were no more likely to have been coerced into sexual activity, and were not significantly more likely to be unhappy or anxious,indeed, men who had engaged in BDSM scored significantly lower on a scale of psychological distress than other men. Engagement in BDSM was not significantly related to any sexual difficulties. Conclusion., Our findings support the idea that BDSM is simply a sexual interest or subculture attractive to a minority, and for most participants not a pathological symptom of past abuse or difficulty with "normal" sex. Richters J, de Visser RO, Rissel CE, Grulich AE, and Smith AMA. Demographic and psychosocial features of participants in bondage and discipline, "sadomasochism" or dominance and submission (BDSM): Data from a national survey. J Sex Med 2008;5:1660,1668. [source] Pilot Study of Sexual Dysfunction Following Abdominal Aortic Aneurysm SurgeryTHE JOURNAL OF SEXUAL MEDICINE, Issue 4ii 2007MRCSI, Vincent Koo MBBCh ABSTRACT Introduction., The complication of sexual dysfunction as a quality of life (QoL) component after abdominal aortic aneurysm (AAA) surgery in men is poorly studied. Aims., To investigate the prevalence of sexual dysfunction and to highlight the importance of discussing this issue with patients undergoing AAA repair. Main Outcome Measures., The self-reported sexual dysfunction prevalence pre- and postoperatively, the effects on sexual QoL, and the postoperative Sexual Health Inventory for Men (SHIM) scores. Methods., Between April 1999 and July 2002, a questionnaire-based study, including the SHIM, was conducted on male patients 1,2 years after their elective open (EO) and rupture open (RO) or endovascular repair (EVAR) AAA repair. Demographics, risk factors for sexual dysfunction, sexual history, and postoperative sexual QoL data were obtained. Results., Out of 142 alive male patients surveyed, 56 (40%) patients responded (26 EO, 21 EVAR, and 9 RO repair). The mean age was 69, 73, and 70 years, respectively, and 65%, 66%, and 66%, respectively, admitted to be sexually active postoperatively. The self-reported sexual dysfunction prevalence preoperatively was 27% (EO), 63% (EVAR), and 45% (RO); and postoperatively was 58%, 76%, and 67%, respectively. Detection using SHIM was higher at 70%, 95%, and 78%, respectively. There was a significantly greater increase in the postoperative prevalence of sexual dysfunction in the EO group than in the EVAR group (P < 0.05, ,2). The sexual QoL was worsened postoperatively in all groups: 53% (EO), 75% (EVAR), and 50% (RO); but only one-third of EO and EVAR patients, and none in RO patients, would seek treatment for their sexual dysfunction. Conclusion., There was a negative impact on the sexual QoL in all groups after surgery, and a significantly higher proportion of patients experienced deterioration in sexual QoL following EO surgical repair. Our results demonstrate the need for a prospective study. Koo V, Lau L, McKinley A, Blair P, and Hood J. Pilot study of sexual dysfunction following abdominal aortic aneurysm surgery. J Sex Med 2007;4:1147,1152. [source] Effects of rapeseed oil replacement in fish feed on lipid composition and self-selection by rainbow trout (Oncorhynchus mykiss)AQUACULTURE NUTRITION, Issue 6 2009A. PETTERSSON Abstract Increased use of plant oils with different origins and quality in fish feed needs to be approached from a food safety and fish welfare point of view. Plant oils contain a number of bioactive minor lipid compounds that may affect the fish's metabolism and taste perception. This study focuses on the effect of replacing fish oil (FO) with different levels of cold-pressed rapeseed oil (RO) on the lipid composition in muscle and liver as well as on the preference by the fish. Rainbow trout (Oncorhynchus mykiss) were fed diets with a FO : RO ratio of 100 : 0, 75 : 25, 50 : 50 and 25 : 75 until twofold weight increase. In self-selecting feed trials of single rainbow trout, fish preferred the diet composed of only FO compared with the diets with RO but did not discriminate between different levels of RO. Plant sterols and their metabolites were found in liver of the fish fed RO diets, suggesting an effect on the sterol metabolism different from fish fed a 100% FO diet. The largest effects were seen in the fatty acid composition of the edible tissue of the fish with a decrease in 22:6n-3 and 20:5n-3 and an increase in 18:2n-6 and 18:1n-9. [source] Effects of dietary protein, and fat level and rapeseed oil on growth and tissue fatty acid composition and metabolism in Atlantic salmon (Salmo salar L.) reared at low water temperaturesAQUACULTURE NUTRITION, Issue 4 2007V. KARALAZOS Abstract A 12-week feeding trial was conducted to elucidate the interactive effects of dietary fat, protein contents and oil source on growth, whole body proximate composition, protein productive value (PPV) and fatty acid (FA) composition of muscle and liver in Atlantic salmon (Salmo salar L.)` at low water temperatures (4.2 °C). Triplicate groups of Atlantic salmon (initial weight 1168 g) were fed six isoenergetic diets, formulated to provide either 390 g kg,1 protein and 320 g kg,1 fat (high-protein diets) or 340 g kg,1 protein and 360 g kg,1 fat (low-protein diets). Within each dietary protein/fat level, crude rapeseed oil (RO) comprised 0, 30 or 60% (R0, R30, R60, respectively) of the added oil. After 12 weeks, the overall growth and feed conversion ratio (FCR) were very good for all treatments [thermal growth coefficient (TGC): 4.76 (±0.23); FCR: 0.85 (±0.02)]. Significant effects were shown owing to the oil source on specific growth rate and TGC only. The liver and muscle FA compositions were highly affected by the graded inclusion of RO. The PPV was significantly affected by the dietary protein level. The results of this study suggest that more sustainable, lower protein diets with moderate RO inclusion can be used in Atlantic salmon culture at low water temperatures with no negative effects on growth and feed conversion, no major detrimental effects on lipid and FA metabolism and a positive effect on protein sparing. [source] The Use of Electrolyzed Solutions for the Cleaning and Disinfecting of DialyzersARTIFICIAL ORGANS, Issue 12 2000Noriaki Tanaka Abstract: Recently, the use of electrolyzed solutions has attracted considerable interest in Japan. This study investigates the efficiency of electrolyzed solutions as disinfecting agents (DA) in the reuse of dialyzers and compares their efficiency to that of other disinfectants currently in use. The following 3 methods were employed. First, the rinsing time and rebound release of reused dialyzers were measured and compared after electrolyzed solutions, electrolyzed strong acid aqueous solution (ESAAS) and electrolyzed strong basic aqueous solution (ESBAS), made from reverse osmosis (RO) water (ESAAS, ESBAS; Generating apparatuses: Super Oxseed , 1000, Amano Corporation, Yokohama, Japan), 2% Dialox-cj (Teijin Gambro Medical, Tokyo, Japan), and 3.8% formalin were used as DAs. This involved performing dialysis with 2 types of dialyzers: a cellulose acetate membrane (CAM) dialyzer and a polysulfone membrane (PSM) dialyzer. The dialyzers were cleaned and disinfected using the different DA and left for 48 h. Next, after performing dialysis the dialyzer membranes were cleaned with a saline solution (0.9% NaCl) and RO water and then cleaned with the various DA. These membranes were observed using a scanning electron microscope (SEM) to check for the presence of physical and biological contaminants. Finally, in vitro tests were performed to determine the level of dialyzer clearance when PSM dialyzers were reused after having been cleaned and disinfected with the electrolyzed solutions. The rinsing time results for both the CAM and PSM dialyzers showed the electrolyzed solutions (ESBAS and ESAAS) as being undetectable within 10 min. With regard to the rebound release, for both the CAM and PSM dialyzers, the electrolyzed solutions were undetectable at all checking times between 30 and 240 min. Observation by SEM showed that cleaning with both ESAAS and ESBAS left the fewest contaminants, and cleaning with 2% Dialox-cj left the highest level of contaminants in the CAM dialyzers. With regard to experiments concerning use in vitro, no major changes in the dialyzer clearance were noticed after 6 uses. In every experiment, the previous investigations showed the electrolyzed solutions to be superior to 3.8% formalin and 2% Dialox-cj DA for the reuse of dialyzers. [source] Does the current World Health Organization classification predict the outcome better in patients with noninvasive bladder cancer of early or regular onset?BJU INTERNATIONAL, Issue 2 2008Maximilian Burger OBJECTIVE To compare the clinical outcome and prognostic power of the former and current World Health Organization (WHO) grading system in patients with early vs regular onset of noninvasive urothelial bladder cancer (UBC), as little is known of the natural history of early onset UBC and in how far it is reflected by histopathological grading and staging in guiding clinical decisions. PATIENTS AND METHODS The medical records of 69 consecutive patients presenting with initial UBC of early onset (,45 years old, EO) and of 100 randomly chosen patients with regular onset (RO) were reviewed. There were no significant differences in gender distribution, risk factors or tumour stage. All histopathological specimens were re-staged and re-graded according to the former and current WHO grading. RESULTS In all, 51 EO and 63 RO patients with tumours staged pTa and complete follow-up information were analysed. Recurrence-free survival (RFS) was prolonged in patients with EO. In EO neither the former nor the current WHO grading system was significantly related to RFS or to progression to muscle-invasive disease. In RO, while both WHO grading systems were significantly related to RFS, only the current WHO grading system was related to progression. CONCLUSION While larger studies are needed, UBC in patients with EO and RO do not seem to differ in risk factors and oncological outcome. The current WHO classification reflects the outcome more accurately than the former classification in patients with RO. However, for EO no grading system has sufficient prognostic power and novel methods, i.e. molecular markers, need to be evaluated for clinical use. [source] Galectin-1 supports the survival of CD45RA(,) primary myeloma cells in vitroBRITISH JOURNAL OF HAEMATOLOGY, Issue 5 2008Saeid Abroun Summary The survival and proliferation of human myeloma cells are considered to be heavily dependent on the microenvironment of bone marrow (BM). This study confirmed that galectin-1 (Gal-1) and SDF-1, were produced by bone marrow mononuclear cells of myeloma patients. The addition of Gal-1 and SDF-1, to a serum-free synthetic medium, maintained the viability of primary myeloma cells for 2 weeks similar to that before culture. While Gal-1 reduced the viable cell number in CD45RA(+) B cell lines, it maintained the viability of CD45(,) U266 and CD45RA(,)RO(+) ILKM3 myeloma cell lines in the synthetic medium. This was confirmed with the transfection of the PTPRC (CD45) RA, -RB, or -RO gene into CD45(,) U266 cells. The combination of Gal-1 and SDF-1, significantly induced phosphorylation of Akt and IkB, while the phosphorylation of ERK1/2 was significantly reduced in CD45RA(+) U266 and Raji cells but not CD45(,) or CD45RA(,) U266 cells. Furthermore, we confirmed that Gal-1 bound to CD45RA in CD45RA(+) Raji cells, and also physically interacted with ,1-integrin by immunoprecipitation followed by Western blotting and confocal microscopy. The results suggest that Gal-1 has two different actions depending on its binding partner, and supports the survival of CD45RA(,) myeloma cells. [source] 5-HT1B but not 5-HT6 or 5-HT7 receptors mediate depression of spinal nociceptive reflexes in vitroBRITISH JOURNAL OF PHARMACOLOGY, Issue 4 2002G Hedo The identity of the serotonin (5-HT) receptors modulating the transmission of segmental C-fibre mediated signals was studied using an in vitro preparation of the hemisected spinal cord from rat pups. Responses to trains of stimuli delivered to a lumbar dorsal root were recorded from the corresponding ventral root. The resulting cumulative depolarization (CD) mediated by unmyelinated fibres was quantified in terms of integrated area. The amplitude of the mono-synaptic reflex was also measured. Serotonergic agents were superfused at known concentrations and their effects on the reflexes evaluated. 5-HT had depressant effects on the CD (EC50 34 ,M). The rank order of potency of agonists for the depression of the CD was 5-carboxamidotryptamine (5-CT)>,-methylserotonin (,-met-5-HT) ,5-HT>42-methylserotonin (2-met-5-HT),8-OH-DPAT. All the agonists including 2-met-5-HT and 8-OH-DPAT had strong depressant effects on the mono-synaptic reflex with the following order of potency: 5-CT>48-OH-DPAT>4,-met-5-HT ,5-HT,2-met-5-HT. The inhibitory effects of 5-HT, ,-met-5-HT and 5-CT were attenuated by the non-specific 5-HT antagonist methiothepin (1 ,M) and by the 5-HT1A/1B antagonist SDZ 21009 (100 nM) but not by the selective 5-HT1A antagonist WAY 100135 (1 ,M). Other antagonists known to block 5-HT2, 5-HT6 and/or 5-HT7 receptors (ketanserin, RO 04-6790, ritanserin and clozapine) did not change the effect of the agonists. The data suggest an important contribution of 5-HT1B receptors to the inhibition of spinal C-fibre mediated nociceptive reflexes but no experimental support was found for the intervention of 5-HT2, 5-HT6 or 5-HT7 receptors in this in vitro model. British Journal of Pharmacology (2002) 135, 935,942; doi:10.1038/sj.bjp.0704526 [source] State of the Art Pump Technology for Reverse Osmosis SystemsCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 1 2003R. Schmitz The industrial significance of diaphragm processes in mass separation is ever increasing; this is particularly true for the use of reverse osmosis (RO) and related methods. Decisive factors for the economy of RO processes, and thus for the future of this technology, are the reliability and energy consumption of the high-pressure pumps involved. Current pump developments reflect clear progress in this field. [source] 4352: Retrobulber imag,ng in glaucoma w,th d,ffus,on tensor MRI/opt,c tractography and fMRI: structural and funct,onal analys,sACTA OPHTHALMOLOGICA, Issue 2010KN ENGIN Purpose Evidences today proves that, glaucomateus damage proceeds from retinal ganglion cells to brain. The purpose of this study is to demonstrate the structural and functional eye-brain connection in glaucoma, to develop favourable clinical methods for both glaucoma follow ups and large clinical trials, and finally, to establish a reference for further studies regarding pathogenesis, evaluation and treatment of glaucoma. Methods Four glaucoma cases with symetrical (n=2) and asymetrical (n=2) involvement and 1 healthy subject are included in this study. Glaucoma analysis with optic coherens tomography (OCT) and central visual field (CVF) results of the subjects were recorded. By using diffusion-tensor magnetic resonance imaging (DT-MRI) technique, 3D-T1 weighted images of the optic nerves and optic tracts were taken with optic tractography (OT). Then DT-MRI parameters obtained from each patient were compared with the fellow eye and the healthy subject. Retinotopic Organizations (RO) of primary visual cortexes were produced from functional magnetic resonance imaging (fMRI) images and BOLD signals were evaluated with reciprocal CVF defects. All images were taken with 1,5T MRI system. Results In DT-MRI analysis, optic nerve volume, FA were found to be decreased in the eyes with severe RNFL loss. Optic nerve and tract deformation were showed with both OT and B0 coronal plane images. Lower bold signals were detected in the eyes of asymetric patients with severe glaucoma and in quadrants with large CVF defects. Conclusion Strategies concerning beyond optic nerve head are needed in glaucoma. Structural and functional analysis can be made by taken together the OCT and DT-MRI findings and CVF and fMRI findings, respectively. [source] | |||||||||||||||||||||||||||||||||||||||||||